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396799eb |
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03-Mar-2024 |
Christoph Hellwig <hch@lst.de> |
md: remove mddev->queue Just use the request_queue from the gendisk pointer in the relatively few places that sill need it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-11-hch@lst.de
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f63f1735 |
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03-Mar-2024 |
Christoph Hellwig <hch@lst.de> |
md/raid5: use the atomic queue limit update APIs Build the queue limits outside the queue and apply them using queue_limits_set. To make the code more obvious also split the queue limits handling into separate helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-8-hch@lst.de
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176df894 |
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03-Mar-2024 |
Christoph Hellwig <hch@lst.de> |
md: add a mddev_is_dm helper Add a helper to check for a DM-mapped MD device instead of using the obfuscated ->gendisk or ->queue NULL checks. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-4-hch@lst.de
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28be4fd3 |
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03-Mar-2024 |
Christoph Hellwig <hch@lst.de> |
md: add a mddev_add_trace_msg helper Add a small wrapper around blk_add_trace_msg that hides some argument dereferences and the check for a DM-mapped MD device. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-3-hch@lst.de
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c396b90e |
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03-Mar-2024 |
Christoph Hellwig <hch@lst.de> |
md: add a mddev_trace_remap helper Add a helper to trace bio remapping that hides some argument dereferences and the check for a DM-mapped MD device. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-2-hch@lst.de
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#
41425f96 |
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05-Mar-2024 |
Yu Kuai <yukuai3@huawei.com> |
dm-raid456, md/raid456: fix a deadlock for dm-raid456 while io concurrent with reshape For raid456, if reshape is still in progress, then IO across reshape position will wait for reshape to make progress. However, for dm-raid, in following cases reshape will never make progress hence IO will hang: 1) the array is read-only; 2) MD_RECOVERY_WAIT is set; 3) MD_RECOVERY_FROZEN is set; After commit c467e97f079f ("md/raid6: use valid sector values to determine if an I/O should wait on the reshape") fix the problem that IO across reshape position doesn't wait for reshape, the dm-raid test shell/lvconvert-raid-reshape.sh start to hang: [root@fedora ~]# cat /proc/979/stack [<0>] wait_woken+0x7d/0x90 [<0>] raid5_make_request+0x929/0x1d70 [raid456] [<0>] md_handle_request+0xc2/0x3b0 [md_mod] [<0>] raid_map+0x2c/0x50 [dm_raid] [<0>] __map_bio+0x251/0x380 [dm_mod] [<0>] dm_submit_bio+0x1f0/0x760 [dm_mod] [<0>] __submit_bio+0xc2/0x1c0 [<0>] submit_bio_noacct_nocheck+0x17f/0x450 [<0>] submit_bio_noacct+0x2bc/0x780 [<0>] submit_bio+0x70/0xc0 [<0>] mpage_readahead+0x169/0x1f0 [<0>] blkdev_readahead+0x18/0x30 [<0>] read_pages+0x7c/0x3b0 [<0>] page_cache_ra_unbounded+0x1ab/0x280 [<0>] force_page_cache_ra+0x9e/0x130 [<0>] page_cache_sync_ra+0x3b/0x110 [<0>] filemap_get_pages+0x143/0xa30 [<0>] filemap_read+0xdc/0x4b0 [<0>] blkdev_read_iter+0x75/0x200 [<0>] vfs_read+0x272/0x460 [<0>] ksys_read+0x7a/0x170 [<0>] __x64_sys_read+0x1c/0x30 [<0>] do_syscall_64+0xc6/0x230 [<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74 This is because reshape can't make progress. For md/raid, the problem doesn't exist because register new sync_thread doesn't rely on the IO to be done any more: 1) If array is read-only, it can switch to read-write by ioctl/sysfs; 2) md/raid never set MD_RECOVERY_WAIT; 3) If MD_RECOVERY_FROZEN is set, mddev_suspend() doesn't hold 'reconfig_mutex', hence it can be cleared and reshape can continue by sysfs api 'sync_action'. However, I'm not sure yet how to avoid the problem in dm-raid yet. This patch on the one hand make sure raid_message() can't change sync_thread() through raid_message() after presuspend(), on the other hand detect the above 3 cases before wait for IO do be done in dm_suspend(), and let dm-raid requeue those IO. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-9-yukuai1@huaweicloud.com
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#
3445139e |
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25-Jan-2024 |
Song Liu <song@kernel.org> |
Revert "Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"" This reverts commit bed9e27baf52a09b7ba2a3714f1e24e17ced386d. The original set [1][2] was expected to undo a suboptimal fix in [2], and replace it with a better fix [1]. However, as reported by Dan Moulding [2] causes an issue with raid5 with journal device. Revert [2] for now to close the issue. We will follow up on another issue reported by Juxiao Bi, as [2] is expected to fix it. We believe this is a good trade-off, because the latter issue happens less freqently. In the meanwhile, we will NOT revert [1], as it contains the right logic. [1] commit d6e035aad6c0 ("md: bypass block throttle for superblock update") [2] commit bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") Reported-by: Dan Moulding <dan@danm.net> Closes: https://lore.kernel.org/linux-raid/20240123005700.9302-1-dan@danm.net/ Fixes: bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") Cc: stable@vger.kernel.org # v5.19+ Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240125082131.788600-1-song@kernel.org
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3a0f007b |
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29-Feb-2024 |
Yu Kuai <yukuai3@huawei.com> |
md: add a new helper rdev_has_badblock() The current api is_badblock() must pass in 'first_bad' and 'bad_sectors', however, many caller just want to know if there are badblocks or not, and these caller must define two local variable that will never be used. Add a new helper rdev_has_badblock() that will only return if there are badblocks or not, remove unnecessary local variables and replace is_badblock() with the new helper in many places. There are no functional changes, and the new helper will also be used later to refactor read_balance(). Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-2-yukuai1@huaweicloud.com
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dfd2bf43 |
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12-Jan-2024 |
Gui-Dong Han <2045gemini@gmail.com> |
md/raid5: fix atomicity violation in raid5_cache_count In raid5_cache_count(): if (conf->max_nr_stripes < conf->min_nr_stripes) return 0; return conf->max_nr_stripes - conf->min_nr_stripes; The current check is ineffective, as the values could change immediately after being checked. In raid5_set_cache_size(): ... conf->min_nr_stripes = size; ... while (size > conf->max_nr_stripes) conf->min_nr_stripes = conf->max_nr_stripes; ... Due to intermediate value updates in raid5_set_cache_size(), concurrent execution of raid5_cache_count() and raid5_set_cache_size() may lead to inconsistent reads of conf->max_nr_stripes and conf->min_nr_stripes. The current checks are ineffective as values could change immediately after being checked, raising the risk of conf->min_nr_stripes exceeding conf->max_nr_stripes and potentially causing an integer overflow. This possible bug is found by an experimental static analysis tool developed by our team. This tool analyzes the locking APIs to extract function pairs that can be concurrently executed, and then analyzes the instructions in the paired functions to identify possible concurrency bugs including data races and atomicity violations. The above possible bug is reported when our tool analyzes the source code of Linux 6.2. To resolve this issue, it is suggested to introduce local variables 'min_stripes' and 'max_stripes' in raid5_cache_count() to ensure the values remain stable throughout the check. Adding locks in raid5_cache_count() fails to resolve atomicity violations, as raid5_set_cache_size() may hold intermediate values of conf->min_nr_stripes while unlocked. With this patch applied, our tool no longer reports the bug, with the kernel configuration allyesconfig for x86_64. Due to the lack of associated hardware, we cannot test the patch in runtime testing, and just verify it according to the code logic. Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han <2045gemini@gmail.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240112071017.16313-1-2045gemini@gmail.com Signed-off-by: Song Liu <song@kernel.org>
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61c90765 |
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28-Dec-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: remove redundant check of 'mddev->sync_thread' The lifetime of sync_thread: 1) Set MD_RECOVERY_NEEDED and wake up daemon thread (by ioctl/sysfs or other events); 2) Daemon thread woke up, md_check_recovery() found that MD_RECOVERY_NEEDED is set: a) try to grab reconfig_mutex; b) set MD_RECOVERY_RUNNING; c) clear MD_RECOVERY_NEEDED, and then queue sync_work; 3) md_start_sync() choose sync_action, then register sync_thread; 4) md_do_sync() is done, set MD_RECOVERY_DONE and wake up daemon thread; 5) Daemon thread woke up, md_check_recovery() found that MD_RECOVERY_DONE is set: a) try to grab reconfig_mutex; b) unregister sync_thread; c) clear MD_RECOVERY_RUNNING and MD_RECOVERY_DONE; Hence there is no such case that MD_RECOVERY_RUNNING is not set, while sync_thread is registered. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231228125553.2697765-2-yukuai1@huaweicloud.com
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ad39c081 |
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01-Feb-2024 |
Yu Kuai <yukuai3@huawei.com> |
md: Don't register sync_thread for reshape directly Currently, if reshape is interrupted, then reassemble the array will register sync_thread directly from pers->run(), in this case 'MD_RECOVERY_RUNNING' is set directly, however, there is no guarantee that md_do_sync() will be executed, hence stop_sync_thread() will hang because 'MD_RECOVERY_RUNNING' can't be cleared. Last patch make sure that md_do_sync() will set MD_RECOVERY_DONE, however, following hang can still be triggered by dm-raid test shell/lvconvert-raid-reshape.sh occasionally: [root@fedora ~]# cat /proc/1982/stack [<0>] stop_sync_thread+0x1ab/0x270 [md_mod] [<0>] md_frozen_sync_thread+0x5c/0xa0 [md_mod] [<0>] raid_presuspend+0x1e/0x70 [dm_raid] [<0>] dm_table_presuspend_targets+0x40/0xb0 [dm_mod] [<0>] __dm_destroy+0x2a5/0x310 [dm_mod] [<0>] dm_destroy+0x16/0x30 [dm_mod] [<0>] dev_remove+0x165/0x290 [dm_mod] [<0>] ctl_ioctl+0x4bb/0x7b0 [dm_mod] [<0>] dm_ctl_ioctl+0x11/0x20 [dm_mod] [<0>] vfs_ioctl+0x21/0x60 [<0>] __x64_sys_ioctl+0xb9/0xe0 [<0>] do_syscall_64+0xc6/0x230 [<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74 Meanwhile mddev->recovery is: MD_RECOVERY_RUNNING | MD_RECOVERY_INTR | MD_RECOVERY_RESHAPE | MD_RECOVERY_FROZEN Fix this problem by remove the code to register sync_thread directly from raid10 and raid5. And let md_check_recovery() to register sync_thread. Fixes: f67055780caa ("[PATCH] md: Checkpoint and allow restart of raid5 reshape") Fixes: f52f5c71f3d4 ("md: fix stopping sync thread") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240201092559.910982-5-yukuai1@huaweicloud.com
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ad860670 |
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25-Nov-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: remove rcu protection to access rdev from conf Because it's safe to accees rdev from conf: - If any spinlock is held, because synchronize_rcu() from md_kick_rdev_from_array() will prevent 'rdev' to be freed until spinlock is released; - If 'reconfig_lock' is held, because rdev can't be added or removed from array; - If there is normal IO inflight, because mddev_suspend() will prevent rdev to be added or removed from array; - If there is sync IO inflight, because 'MD_RECOVERY_RUNNING' is checked in remove_and_add_spares(). And these will cover all the scenarios in raid456. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231125081604.3939938-5-yukuai1@huaweicloud.com
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c891f1fd |
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25-Nov-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: remove flag RemoveSynchronized rcu is not used correctly here, because synchronize_rcu() is called before replacing old value, for example: remove_and_add_spares // other path synchronize_rcu // called before replacing old value set_bit(RemoveSynchronized) rcu_read_lock() rdev = conf->mirros[].rdev pers->hot_remove_disk conf->mirros[].rdev = NULL; if (!test_bit(RemoveSynchronized)) synchronize_rcu /* * won't be called, and won't wait * for concurrent readers to be done. */ // access rdev after remove_and_add_spares() rcu_read_unlock() Fortunately, there is a separate rcu protection to prevent such rdev to be freed: md_kick_rdev_from_array //other path rcu_read_lock() rdev = conf->mirros[].rdev list_del_rcu(&rdev->same_set) rcu_read_unlock() /* * rdev can be removed from conf, but * rdev won't be freed. */ synchronize_rcu() free rdev Hence remove this useless flag and prepare to remove rcu protection to access rdev from 'conf'. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231125081604.3939938-2-yukuai1@huaweicloud.com
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bed9e27b |
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08-Nov-2023 |
Junxiao Bi <junxiao.bi@oracle.com> |
Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d" This reverts commit 5e2cf333b7bd5d3e62595a44d598a254c697cd74. That commit introduced the following race and can cause system hung. md_write_start: raid5d: // mddev->in_sync == 1 set "MD_SB_CHANGE_PENDING" // running before md_write_start wakeup it waiting "MD_SB_CHANGE_PENDING" cleared >>>>>>>>> hung wakeup mddev->thread ... waiting "MD_SB_CHANGE_PENDING" cleared >>>> hung, raid5d should clear this flag but get hung by same flag. The issue reverted commit fixing is fixed by last patch in a new way. Fixes: 5e2cf333b7bd ("md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d") Cc: stable@vger.kernel.org # v5.19+ Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231108182216.73611-2-junxiao.bi@oracle.com
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c467e97f |
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28-Nov-2023 |
David Jeffery <djeffery@redhat.com> |
md/raid6: use valid sector values to determine if an I/O should wait on the reshape During a reshape or a RAID6 array such as expanding by adding an additional disk, I/Os to the region of the array which have not yet been reshaped can stall indefinitely. This is from errors in the stripe_ahead_of_reshape function causing md to think the I/O is to a region in the actively undergoing the reshape. stripe_ahead_of_reshape fails to account for the q disk having a sector value of 0. By not excluding the q disk from the for loop, raid6 will always generate a min_sector value of 0, causing a return value which stalls. The function's max_sector calculation also uses min() when it should use max(), causing the max_sector value to always be 0. During a backwards rebuild this can cause the opposite problem where it allows I/O to advance when it should wait. Fixing these errors will allow safe I/O to advance in a timely manner and delay only I/O which is unsafe due to stripes in the middle of undergoing the reshape. Fixes: 486f60558607 ("md/raid5: Check all disks in a stripe_head for reshape progress") Cc: stable@vger.kernel.org # v6.0+ Signed-off-by: David Jeffery <djeffery@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231128181233.6187-1-djeffery@redhat.com
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78b7b13f |
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16-Oct-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: cleanup pers->prepare_suspend() pers->prepare_suspend() is not used anymore and can be removed. Reverts following three commit: - commit 431e61257d63 ("md: export md_is_rdwr() and is_md_suspended()") - commit 3e00777d5157 ("md: add a new api prepare_suspend() in md_personality") - commit 868bba54a3bc ("md/raid5: fix a deadlock in the case that reshape is interrupted") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231016100240.540474-1-yukuai1@huaweicloud.com
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b42cd7b3 |
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10-Oct-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: replace suspend with quiesce() callback raid5 is the only personality to suspend array in check_reshape() and start_reshape() callback, suspend and quiesce() callback can both wait for all normal io to be done, and prevent new io to be dispatched, the difference is that suspend is implemented in common layer, and quiesce() callback is implemented in raid5. In order to cleanup all the usage of mddev_suspend(), the new apis __mddev_suspend() need to be called before 'reconfig_mutex' is held, and it's not good to affect all the personalities in common layer just for raid5. Hence replace suspend with quiesce() callaback, prepare to reomove all the users of mddev_suspend(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231010151958.145896-17-yukuai1@huaweicloud.com
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e28ca92f |
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10-Oct-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: use new apis to suspend array Convert to use new apis, the old apis will be removed eventually. These are not hot path, so performance is not concerned. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231010151958.145896-10-yukuai1@huaweicloud.com
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86298d8b |
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11-Sep-2023 |
Qi Zheng <zhengqi.arch@bytedance.com> |
md/raid5: dynamically allocate the md-raid5 shrinker In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the md-raid5 shrinker, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct r5conf. Link: https://lkml.kernel.org/r/20230911094444.68966-26-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Song Liu <song@kernel.org> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Anna Schumaker <anna@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bob Peterson <rpeterso@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Carlos Llamas <cmllamas@google.com> Cc: Chandan Babu R <chandan.babu@oracle.com> Cc: Chao Yu <chao@kernel.org> Cc: Chris Mason <clm@fb.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christian Koenig <christian.koenig@amd.com> Cc: Chuck Lever <cel@kernel.org> Cc: Coly Li <colyli@suse.de> Cc: Dai Ngo <Dai.Ngo@oracle.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Airlie <airlied@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Sterba <dsterba@suse.com> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Cc: Gao Xiang <hsiangkao@linux.alibaba.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Huang Rui <ray.huang@amd.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Wang <jasowang@redhat.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jeffle Xu <jefflexu@linux.alibaba.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Kirill Tkhai <tkhai@ya.ru> Cc: Marijn Suijten <marijn.suijten@somainline.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Mike Snitzer <snitzer@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nadav Amit <namit@vmware.com> Cc: Neil Brown <neilb@suse.de> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Olga Kornievskaia <kolga@netapp.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rob Clark <robdclark@gmail.com> Cc: Rob Herring <robh@kernel.org> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Sean Paul <sean@poorly.run> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Steven Price <steven.price@arm.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com> Cc: Tom Talpey <tom@talpey.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: Yue Hu <huyue2@coolpad.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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b8494823 |
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24-Aug-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: initialize 'writes_pending' while allocating mddev Currently 'writes_pending' is initialized in pers->run for raid1/5/10, and it's freed while deleing mddev, instead of pers->free. pers->run can be called multiple times before mddev is deleted, and a helper mddev_init_writes_pending() is used to prevent 'writes_pending' to be initialized multiple times, this usage is safe but a litter weird. On the other hand, 'writes_pending' is only initialized for raid1/5/10, however, it's used in common layer, for example: array_state_store set_in_sync if (!mddev->in_sync) -> in_sync is used for all levels // access writes_pending There might be some implicit dependency that I don't recognized to make sure 'writes_pending' can only be accessed for raid1/5/10, but there are no comments about that. By the way, it make sense to initialize 'writes_pending' in common layer because there are already three levels use it. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230825030956.1527023-3-yukuai1@huaweicloud.com
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2fd7b0f6 |
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02-Oct-2023 |
David Jeffery <djeffery@redhat.com> |
md/raid5: release batch_last before waiting for another stripe_head When raid5_get_active_stripe is called with a ctx containing a stripe_head in its batch_last pointer, it can cause a deadlock if the task sleeps waiting on another stripe_head to become available. The stripe_head held by batch_last can be blocking the advancement of other stripe_heads, leading to no stripe_heads being released so raid5_get_active_stripe waits forever. Like with the quiesce state handling earlier in the function, batch_last needs to be released by raid5_get_active_stripe before it waits for another stripe_head. Fixes: 3312e6c887fe ("md/raid5: Keep a reference to last stripe_head for batch") Cc: stable@vger.kernel.org # v6.0+ Signed-off-by: David Jeffery <djeffery@redhat.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20231002183422.13047-1-djeffery@redhat.com
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7eb8ff02 |
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03-Aug-2023 |
Li Lingfeng <lilingfeng3@huawei.com> |
md: Hold mddev->reconfig_mutex when trying to get mddev->sync_thread Commit ba9d9f1a707f ("Revert "md: unlock mddev before reap sync_thread in action_store"") removed the scenario of calling md_unregister_thread() without holding mddev->reconfig_mutex, so add a lock holding check before acquiring mddev->sync_thread by passing mdev to md_unregister_thread(). Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20230803071711.2546560-1-lilingfeng@huaweicloud.com Signed-off-by: Song Liu <song@kernel.org>
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05048cbc |
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21-Jun-2023 |
Yu Kuai <yukuai3@huawei.com> |
raid5: fix missing io accounting in raid5_align_endio() Io will only be accounted as done from raid5_align_endio() if the io succeeded, and io inflight counter will be leaked if such io failed. Fix this problem by switching to use md_account_bio() for io accounting. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230621165110.1498313-4-yukuai1@huaweicloud.com
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c687297b |
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21-Jun-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: also clone new io if io accounting is disabled Currently, 'active_io' is grabbed before make_reqeust() is called, and it's dropped immediately make_reqeust() returns. Hence 'active_io' actually means io is dispatching, not io is inflight. For raid0 and raid456 that io accounting is enabled, 'active_io' will also be grabbed when bio is cloned for io accounting, and this 'active_io' is dropped until io is done. Always clone new bio so that 'active_io' will mean that io is inflight, raid1 and raid10 will switch to use this method in later patches. Now that bio will be cloned even if io accounting is disabled, also rename related structure from '*_acct_*' to '*_clone_*'. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230621165110.1498313-3-yukuai1@huaweicloud.com
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c567c86b |
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21-Jun-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: move initialization and destruction of 'io_acct_set' to md.c 'io_acct_set' is only used for raid0 and raid456, prepare to use it for raid1 and raid10, so that io accounting from different levels can be consistent. By the way, follow up patches will also use this io clone mechanism to make sure 'active_io' represents in flight io, not io that is dispatching, so that mddev_suspend will wait for io to be done as designed. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230621165110.1498313-2-yukuai1@huaweicloud.com
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75aa7a1b |
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29-May-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: don't start reshape when recovery or replace is in progress When recovery is interrupted (reboot, etc.) check for MD_RECOVERY_RUNNING is not enough to tell recovery is in progress. Also check recovery_cp before starting reshape. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230529133410.2125914-1-yukuai1@huaweicloud.com
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44693154 |
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22-May-2023 |
Yu Kuai <yukuai3@huawei.com> |
md: protect md_thread with rcu Currently, there are many places that md_thread can be accessed without protection, following are known scenarios that can cause null-ptr-dereference or uaf: 1) sync_thread that is allocated and started from md_start_sync() 2) mddev->thread can be accessed directly from timeout_store() and md_bitmap_daemon_work() 3) md_unregister_thread() from action_store(). Currently, a global spinlock 'pers_lock' is borrowed to protect 'mddev->thread' in some places, this problem can be fixed likewise, however, use a global lock for all the cases is not good. Fix this problem by protecting all md_thread with rcu. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230523021017.3048783-6-yukuai1@huaweicloud.com
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868bba54 |
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11-May-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: fix a deadlock in the case that reshape is interrupted If reshape is in progress and io across reshape_position is issued, such io will wait for reshape to make progress(see details in the case that make_stripe_request() return STRIPE_SCHEDULE_AND_RETRY). It has been reported several times that if system reboot while growing raid5 to raid6, array assemble will hang infinitely([1, 2]). This is because following deadlock is triggered: 1) a normal io is waiting for reshape to progress, this io can be from system-udevd or mdadm. 2) while assemble, mdadm tries to suspend the array, hence 'reconfig_mutex' is held and mddev_suspend() must wait for normal io to be done. 3) daemon thread can't start reshape because 'reconfig_mutex' can't be held. 1) and 3) is unbreakable because they're foundation design. In order to break 2), following is possible solutions that I can think of: a) Let mddev_suspend() fail is not a good option, because this will break many scenarios since mddev_suspend() doesn't fail before. b) Fail the io that is waiting for reshape to make progress from mddev_suspend(). c) Return false for the io that is waiting for reshape to make progress from raid5_make_request(), and these io will wait for suspend to be done in md_handle_request(), where 'active_io' is not grabbed. c) sounds better than b), however, b) is used because it's easy and straightforward, and it's verified that mdadm can assemble in this case. On the other hand, c) breaks the logic that mddev_suspend() will wait for submitted io to be completely handled. Fix the problem by checking reshape in mddev_suspend(), if reshape can't make progress and there are still some io waiting for reshape, fail those io. [1] https://lore.kernel.org/all/CAFig2csUV2QiomUhj_t3dPOgV300dbQ6XtM9ygKPdXJFSH__Nw@mail.gmail.com/ [2] https://lore.kernel.org/all/CAO2ABipzbw6QL5eNa44CQHjiVa-LTvS696Mh9QaTw+qsUKFUCw@mail.gmail.com/ Reported-by: Jove <jovetoo@gmail.com> Reported-by: David Gilmour <dgilmour76@gmail.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230512015610.821290-6-yukuai1@huaweicloud.com
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46038b30 |
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11-May-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: don't allow replacement while reshape is in progress If reshape is interrupted(for example, echo frozen to sync_action), then rdev replacement can be set. It's safe because reshape is always prior to resync in md_check_recovery(). However, if system reboots, then kernel will complain cannot handle concurrent replacement and reshape and this array is not able to assemble anymore. Fix this problem by don't allow replacement until reshape is done. Reported-by: Peter Neuwirth <reddunur@online.de> Link: https://lore.kernel.org/linux-raid/e2f96772-bfbc-f43b-6da1-f520e5164536@online.de/ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230512015610.821290-2-yukuai1@huaweicloud.com
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2f088dfc |
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12-May-2023 |
Kees Cook <keescook@chromium.org> |
md/raid5: Convert stripe_head's "dev" to flexible array member Replace old-style 1-element array of "dev" in struct stripe_head with modern C99 flexible array. In the future, we can additionally annotate it with the run-time size, found in the "disks" member. Cc: Song Liu <song@kernel.org> Cc: linux-raid@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/lkml/20230522212114.gonna.589-kees@kernel.org/ --- It looks like this memory calculation: memory = conf->min_nr_stripes * (sizeof(struct stripe_head) + max_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; ... was already buggy (i.e. it included the single "dev" bytes in the result). However, I'm not entirely sure if that is the right analysis, since "dev" is not related to struct bio nor PAGE_SIZE?
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8557dc27 |
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23-May-2023 |
Yu Kuai <yukuai3@huawei.com> |
md/raid5: fix miscalculation of 'end_sector' in raid5_read_one_chunk() 'end_sector' is compared to 'rdev->recovery_offset', which is offset to rdev, however, commit e82ed3a4fbb5 ("md/raid6: refactor raid5_read_one_chunk") changes the calculation of 'end_sector' to offset to the array. Fix this miscalculation. Fixes: e82ed3a4fbb5 ("md/raid6: refactor raid5_read_one_chunk") Cc: stable@vger.kernel.org # v5.12+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230524014118.3172781-1-yukuai1@huaweicloud.com
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fc05e06e |
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17-Apr-2023 |
Jan Kara <jack@suse.cz> |
md/raid5: Improve performance for sequential IO Commit 7e55c60acfbb ("md/raid5: Pivot raid5_make_request()") changed the order in which requests for underlying disks are created. Since for large sequential IO adding of requests frequently races with md_raid5 thread submitting bios to underlying disks, this results in a change in IO pattern because intermediate states of new order of request creation result in more smaller discontiguous requests. For RAID5 on top of three rotational disks our performance testing revealed this results in regression in write throughput: iozone -a -s 131072000 -y 4 -q 8 -i 0 -i 1 -R before 7e55c60acfbb: KB reclen write rewrite read reread 131072000 4 493670 525964 524575 513384 131072000 8 540467 532880 512028 513703 after 7e55c60acfbb: KB reclen write rewrite read reread 131072000 4 421785 456184 531278 509248 131072000 8 459283 456354 528449 543834 To reduce the amount of discontiguous requests we can start generating requests with the stripe with the lowest chunk offset as that has the best chance of being adjacent to IO queued previously. This improves the performance to: KB reclen write rewrite read reread 131072000 4 497682 506317 518043 514559 131072000 8 514048 501886 506453 504319 restoring big part of the regression. Fixes: 7e55c60acfbb ("md/raid5: Pivot raid5_make_request()") Cc: stable@vger.kernel.org # v6.0+ Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230417171537.17899-1-jack@suse.cz
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7bc43612 |
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27-Mar-2023 |
Tom Rix <trix@redhat.com> |
md/raid5: remove unused working_disks variable clang with W=1 reports drivers/md/raid5.c:7719:6: error: variable 'working_disks' set but not used [-Werror,-Wunused-but-set-variable] int working_disks = 0; ^ This variable is not used so remove it. Signed-off-by: Tom Rix <trix@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20230327132324.1769595-1-trix@redhat.com
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5e2cf333 |
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21-Sep-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d A complicated deadlock exists when using the journal and an elevated group_thrtead_cnt. It was found with loop devices, but its not clear whether it can be seen with real disks. The deadlock can occur simply by writing data with an fio script. When the deadlock occurs, multiple threads will hang in different ways: 1) The group threads will hang in the blk-wbt code with bios waiting to be submitted to the block layer: io_schedule+0x70/0xb0 rq_qos_wait+0x153/0x210 wbt_wait+0x115/0x1b0 io_schedule+0x70/0xb0 rq_qos_wait+0x153/0x210 wbt_wait+0x115/0x1b0 __rq_qos_throttle+0x38/0x60 blk_mq_submit_bio+0x589/0xcd0 wbt_wait+0x115/0x1b0 __rq_qos_throttle+0x38/0x60 blk_mq_submit_bio+0x589/0xcd0 __submit_bio+0xe6/0x100 submit_bio_noacct_nocheck+0x42e/0x470 submit_bio_noacct+0x4c2/0xbb0 ops_run_io+0x46b/0x1a30 handle_stripe+0xcd3/0x36b0 handle_active_stripes.constprop.0+0x6f6/0xa60 raid5_do_work+0x177/0x330 Or: io_schedule+0x70/0xb0 rq_qos_wait+0x153/0x210 wbt_wait+0x115/0x1b0 __rq_qos_throttle+0x38/0x60 blk_mq_submit_bio+0x589/0xcd0 __submit_bio+0xe6/0x100 submit_bio_noacct_nocheck+0x42e/0x470 submit_bio_noacct+0x4c2/0xbb0 flush_deferred_bios+0x136/0x170 raid5_do_work+0x262/0x330 2) The r5l_reclaim thread will hang in the same way, submitting a bio to the block layer: io_schedule+0x70/0xb0 rq_qos_wait+0x153/0x210 wbt_wait+0x115/0x1b0 __rq_qos_throttle+0x38/0x60 blk_mq_submit_bio+0x589/0xcd0 __submit_bio+0xe6/0x100 submit_bio_noacct_nocheck+0x42e/0x470 submit_bio_noacct+0x4c2/0xbb0 submit_bio+0x3f/0xf0 md_super_write+0x12f/0x1b0 md_update_sb.part.0+0x7c6/0xff0 md_update_sb+0x30/0x60 r5l_do_reclaim+0x4f9/0x5e0 r5l_reclaim_thread+0x69/0x30b However, before hanging, the MD_SB_CHANGE_PENDING flag will be set for sb_flags in r5l_write_super_and_discard_space(). This flag will never be cleared because the submit_bio() call never returns. 3) Due to the MD_SB_CHANGE_PENDING flag being set, handle_stripe() will do no processing on any pending stripes and re-set STRIPE_HANDLE. This will cause the raid5d thread to enter an infinite loop, constantly trying to handle the same stripes stuck in the queue. The raid5d thread has a blk_plug that holds a number of bios that are also stuck waiting seeing the thread is in a loop that never schedules. These bios have been accounted for by blk-wbt thus preventing the other threads above from continuing when they try to submit bios. --Deadlock. To fix this, add the same wait_event() that is used in raid5_do_work() to raid5d() such that if MD_SB_CHANGE_PENDING is set, the thread will schedule and wait until the flag is cleared. The schedule action will flush the plug which will allow the r5l_reclaim thread to continue, thus preventing the deadlock. However, md_check_recovery() calls can also clear MD_SB_CHANGE_PENDING from the same thread and can thus deadlock if the thread is put to sleep. So avoid waiting if md_check_recovery() is being called in the loop. It's not clear when the deadlock was introduced, but the similar wait_event() call in raid5_do_work() was added in 2017 by this commit: 16d997b78b15 ("md/raid5: simplfy delaying of writes while metadata is updated.") Link: https://lore.kernel.org/r/7f3b87b6-b52a-f737-51d7-a4eec5c44112@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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c66a6f41 |
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08-Sep-2022 |
David Sloan <david.sloan@eideticom.com> |
md/raid5: Remove unnecessary bio_put() in raid5_read_one_chunk() When running chunk-sized reads on disks with badblocks duplicate bio free/puts are observed: ============================================================================= BUG bio-200 (Not tainted): Object already free ----------------------------------------------------------------------------- Allocated in mempool_alloc_slab+0x17/0x20 age=3 cpu=2 pid=7504 __slab_alloc.constprop.0+0x5a/0xb0 kmem_cache_alloc+0x31e/0x330 mempool_alloc_slab+0x17/0x20 mempool_alloc+0x100/0x2b0 bio_alloc_bioset+0x181/0x460 do_mpage_readpage+0x776/0xd00 mpage_readahead+0x166/0x320 blkdev_readahead+0x15/0x20 read_pages+0x13f/0x5f0 page_cache_ra_unbounded+0x18d/0x220 force_page_cache_ra+0x181/0x1c0 page_cache_sync_ra+0x65/0xb0 filemap_get_pages+0x1df/0xaf0 filemap_read+0x1e1/0x700 blkdev_read_iter+0x1e5/0x330 vfs_read+0x42a/0x570 Freed in mempool_free_slab+0x17/0x20 age=3 cpu=2 pid=7504 kmem_cache_free+0x46d/0x490 mempool_free_slab+0x17/0x20 mempool_free+0x66/0x190 bio_free+0x78/0x90 bio_put+0x100/0x1a0 raid5_make_request+0x2259/0x2450 md_handle_request+0x402/0x600 md_submit_bio+0xd9/0x120 __submit_bio+0x11f/0x1b0 submit_bio_noacct_nocheck+0x204/0x480 submit_bio_noacct+0x32e/0xc70 submit_bio+0x98/0x1a0 mpage_readahead+0x250/0x320 blkdev_readahead+0x15/0x20 read_pages+0x13f/0x5f0 page_cache_ra_unbounded+0x18d/0x220 Slab 0xffffea000481b600 objects=21 used=0 fp=0xffff8881206d8940 flags=0x17ffffc0010201(locked|slab|head|node=0|zone=2|lastcpupid=0x1fffff) CPU: 0 PID: 34525 Comm: kworker/u24:2 Not tainted 6.0.0-rc2-localyes-265166-gf11c5343fa3f #143 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: raid5wq raid5_do_work Call Trace: <TASK> dump_stack_lvl+0x5a/0x78 dump_stack+0x10/0x16 print_trailer+0x158/0x165 object_err+0x35/0x50 free_debug_processing.cold+0xb7/0xbe __slab_free+0x1ae/0x330 kmem_cache_free+0x46d/0x490 mempool_free_slab+0x17/0x20 mempool_free+0x66/0x190 bio_free+0x78/0x90 bio_put+0x100/0x1a0 mpage_end_io+0x36/0x150 bio_endio+0x2fd/0x360 md_end_io_acct+0x7e/0x90 bio_endio+0x2fd/0x360 handle_failed_stripe+0x960/0xb80 handle_stripe+0x1348/0x3760 handle_active_stripes.constprop.0+0x72a/0xaf0 raid5_do_work+0x177/0x330 process_one_work+0x616/0xb20 worker_thread+0x2bd/0x6f0 kthread+0x179/0x1b0 ret_from_fork+0x22/0x30 </TASK> The double free is caused by an unnecessary bio_put() in the if(is_badblock(...)) error path in raid5_read_one_chunk(). The error path was moved ahead of bio_alloc_clone() in c82aa1b76787c ("md/raid5: move checking badblock before clone bio in raid5_read_one_chunk"). The previous code checked and freed align_bio which required a bio_put. After the move that is no longer needed as raid_bio is returned to the control of the common io path which performs its own endio resulting in a double free on bad device blocks. Fixes: c82aa1b76787c ("md/raid5: move checking badblock before clone bio in raid5_read_one_chunk") Signed-off-by: David Sloan <david.sloan@eideticom.com> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Guoqing Jiang <Guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org>
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e2eed85b |
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25-Aug-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Ensure stripe_fill happens on non-read IO with journal When doing degrade/recover tests using the journal a kernel BUG is hit at drivers/md/raid5.c:4381 in handle_parity_checks5(): BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); This was found to occur because handle_stripe_fill() was skipped for stripes in the journal due to a condition in that function. Thus blocks were not fetched and R5_UPTODATE was not set when the code reached handle_parity_checks5(). To fix this, don't skip handle_stripe_fill() unless the stripe is for read. Fixes: 07e83364845e ("md/r5cache: shift complex rmw from read path to write path") Link: https://lore.kernel.org/linux-raid/e05c4239-41a9-d2f7-3cfa-4aa9d2cea8c1@deltatee.com/ Suggested-by: Song Liu <song@kernel.org> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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f9287c3e |
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11-Aug-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Don't read ->active_stripes if it's not needed The atomic_read() is not needed in many cases so only do the read after the first checks are done. Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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2f2d51ef |
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11-Aug-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Cleanup prototype of raid5_get_active_stripe() Drop the three bools in the prototype of raid5_get_active_stripe() and replace them with a flags parameter. At the same time, drop the distinction with __raid5_get_active_stripe(). Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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b6d56144 |
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11-Aug-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Refactor raid5_get_active_stripe() Refactor raid5_get_active_stripe() without the gotos with an explicit infinite loop and some additional nesting. Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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e33c267a |
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31-May-2022 |
Roman Gushchin <roman.gushchin@linux.dev> |
mm: shrinkers: provide shrinkers with names Currently shrinkers are anonymous objects. For debugging purposes they can be identified by count/scan function names, but it's not always useful: e.g. for superblock's shrinkers it's nice to have at least an idea of to which superblock the shrinker belongs. This commit adds names to shrinkers. register_shrinker() and prealloc_shrinker() functions are extended to take a format and arguments to master a name. In some cases it's not possible to determine a good name at the time when a shrinker is allocated. For such cases shrinker_debugfs_rename() is provided. The expected format is: <subsystem>-<shrinker_type>[:<instance>]-<id> For some shrinkers an instance can be encoded as (MAJOR:MINOR) pair. After this change the shrinker debugfs directory looks like: $ cd /sys/kernel/debug/shrinker/ $ ls dquota-cache-16 sb-devpts-28 sb-proc-47 sb-tmpfs-42 mm-shadow-18 sb-devtmpfs-5 sb-proc-48 sb-tmpfs-43 mm-zspool:zram0-34 sb-hugetlbfs-17 sb-pstore-31 sb-tmpfs-44 rcu-kfree-0 sb-hugetlbfs-33 sb-rootfs-2 sb-tmpfs-49 sb-aio-20 sb-iomem-12 sb-securityfs-6 sb-tracefs-13 sb-anon_inodefs-15 sb-mqueue-21 sb-selinuxfs-22 sb-xfs:vda1-36 sb-bdev-3 sb-nsfs-4 sb-sockfs-8 sb-zsmalloc-19 sb-bpf-32 sb-pipefs-14 sb-sysfs-26 thp-deferred_split-10 sb-btrfs:vda2-24 sb-proc-25 sb-tmpfs-1 thp-zero-9 sb-cgroup2-30 sb-proc-39 sb-tmpfs-27 xfs-buf:vda1-37 sb-configfs-23 sb-proc-41 sb-tmpfs-29 xfs-inodegc:vda1-38 sb-dax-11 sb-proc-45 sb-tmpfs-35 sb-debugfs-7 sb-proc-46 sb-tmpfs-40 [roman.gushchin@linux.dev: fix build warnings] Link: https://lkml.kernel.org/r/Yr+ZTnLb9lJk6fJO@castle Reported-by: kernel test robot <lkp@intel.com> Link: https://lkml.kernel.org/r/20220601032227.4076670-4-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Dave Chinner <dchinner@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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10421247 |
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28-Jul-2022 |
Wentao_Liang <Wentao_Liang_g@163.com> |
drivers:md:fix a potential use-after-free bug In line 2884, "raid5_release_stripe(sh);" drops the reference to sh and may cause sh to be released. However, sh is subsequently used in lines 2886 "if (sh->batch_head && sh != sh->batch_head)". This may result in an use-after-free bug. It can be fixed by moving "raid5_release_stripe(sh);" to the bottom of the function. Signed-off-by: Wentao_Liang <Wentao_Liang_g@163.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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20313b1b |
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27-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Ensure batch_last is released before sleeping for quiesce A race condition exists where if raid5_quiesce() is called in the middle of a request that has set batch_last, it will deadlock. batch_last will hold a reference to a stripe when raid5_quiesce() is called. This will cause the next raid5_get_active_stripe() call to sleep waiting for the quiesce to finish, but the raid5_quiesce() thread will wait for active_stripes to go to zero which will never happen because request thread is waiting for the quiesce to stop. Fix this by creating a special __raid5_get_active_stripe() function which takes the request context and clears the last_batch before sleeping. While we're at it, change the arguments of raid5_get_active_stripe() to bools. Fixes: 3312e6c887fe ("md/raid5: Keep a reference to last stripe_head for batch") Reported-by: David Sloan <David.Sloan@eideticom.com> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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df6b0e20 |
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27-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Move stripe_request_ctx up Move stripe_request_ctx up. No functional changes intended. This will be necessary in the next patch to release the batch_last in the context before sleeping. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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9734fe7b |
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27-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Drop unnecessary call to r5c_check_stripe_cache_usage() Now that raid5_get_active_stripe() has been refactored it is appearant that r5c_check_stripe_cache_usage() doesn't need to be called in the wait_for_stripe branch. r5c_check_stripe_cache_usage() will only conditionally call r5l_wake_reclaim(), but that function is called two lines later. Drop the call for cleanup. Reported-by: Martin Oliveira <martin.oliveira@eideticom.com> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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3514da58 |
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27-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Make is_inactive_blocked() helper The logic to wait_for_stripe is difficult to parse being on so many lines and with confusing operator precedence. Move it to a helper function to make it easier to read. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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5165ed40 |
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27-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Refactor raid5_get_active_stripe() Refactor the raid5_get_active_stripe() to read more linearly in the order it's typically executed. The init_stripe() call is called if a free stripe is found and the function is exited early which removes a lot of if (sh) checks and unindents the following code. Remove the while loop in favour of the 'goto retry' pattern, which reduces indentation further. And use a 'goto wait_for_stripe' instead of an additional indent seeing it is the unusual path and this makes the code easier to read. No functional changes intended. Will make subsequent changes in patches easier to understand. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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a20d636b |
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07-Jul-2022 |
Jackie Liu <liuyun01@kylinos.cn> |
raid5: fix duplicate checks for rdev->saved_raid_disk 'first' will always be greater than or equal to 0, it is unnecessary to repeat the 0 check, clean it up. Signed-off-by: Jackie Liu <liuyun01@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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ee1aa06b |
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07-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Convert prepare_to_wait() to wait_woken() api raid5_get_active_stripe() can sleep in various situations and it is called by make_stripe_request() while inside the prepare_to_wait()/finish_wait() section. Nested waits like this are not supported. This was noticed while making other changes that add different sleeps to raid5_get_active_stripe() that caused a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP. No ill effects have been noticed with the code as is, but theoretically a nested and here could cause a dead lock so it should be fixed. To fix this, convert the prepare_to_wait() call to use wake_woken() which supports nested sleeps. Link: https://lwn.net/Articles/628628/ Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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b9f91d80 |
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07-Jul-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Fix sectors_to_do bitmap overflow in raid5_make_request() For unaligned IO that have nearly maximum sectors, the number of stripes will end up being one greater than the size of the bitmap. When this happens, the last stripe in the IO will not be processed as it should be, resulting in data corruption. However, this is not normally seen when the backing block devices have 4K physical block sizes since the block layer will split the request before that happens. To fix this increase the bitmap size by one bit and ensure the full number of stripes are checked when calling find_first_bit(). Reported-by: David Sloan <David.Sloan@eideticom.com> Fixes: 7e55c60acfbb ("md/raid5: Pivot raid5_make_request()") Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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9ad1a74f |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Increase restriction on max segments per request The block layer defaults the maximum segments to 128, which means requests tend to get split around the 512KB depending on how many pages can be merged. There's no such restriction in the raid5 code so increase the limit to USHRT_MAX so that larger requests can be sent as one. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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df1b620a |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Improve debug prints Add a debug print for raid5_make_request() so that each request is printed and add the logical sector number to the debug print in __add_stripe_bio(). Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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7e55c60a |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Pivot raid5_make_request() raid5_make_request() loops through every page in the request, finds the appropriate stripe and adds the bio for that page in the disk. This causes a great deal of contention on the hash_lock and extra work seeing each stripe must be found once for every data disk. The number of times a stripe must be found can be reduced by pivoting raid5_make_request() so that it loops through every stripe and then loops through every disk in that stripe to see if the bio must be added. This reduces the number of times the hash lock must be taken by a factor equal to the number of data disks. To accomplish this, the logical sectors that have already been added must be tracked. Tracking them is done with a bitmap: the bits for all pages are set at the start of the request and each bit is cleared once the bio is added to a stripe. Finding the next sector to be done is then just a call to find_first_bit() so that sectors that have been done can simply be skipped. One minor downside is that the maximum sectors for a request must be limited so that the bitmap can be appropriately sized on the stack. This limit is arbitrarily chosen to be 256 stripe pages which works out to 1MB if PAGE_SIZE == DEFAULT_STRIPE_SIZE. This doesn't actually restrict the maximum request further seeing the default block queue settings are used which restricts the number of segments to 128 (which results in request sizes that are approximately 512KB). Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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486f6055 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Check all disks in a stripe_head for reshape progress When testing if a previous stripe has had reshape expand past it, use the earliest or latest logical sector in all the disks for that stripe head. This will allow adding multiple disks at a time in a subesquent patch. To do this cleaner, refactor the check into a helper function called stripe_ahead_of_reshape(). Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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4ad1d984 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Refactor add_stripe_bio() Factor out two helper functions from add_stripe_bio(): one to check for overlap (stripe_bio_overlaps()), and one to actually add the bio to the stripe (__add_stripe_bio()). The latter function will always succeed. This will be useful in the next patch so that overlap can be checked for multiple disks before adding any Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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3312e6c8 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Keep a reference to last stripe_head for batch When batching, every stripe head has to find the previous stripe head to add to the batch list. This involves taking the hash lock which is highly contended during IO. Instead of finding the previous stripe_head each time, store a reference to the previous stripe_head in a pointer so that it doesn't require taking the contended lock another time. The reference to the previous stripe must be released before scheduling and waiting for work to get done. Otherwise, it can hold up raid5_activate_delayed() and deadlock. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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0a2d1694 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Refactor for loop in raid5_make_request() into while loop The for loop with retry label can be more cleanly expressed as a while loop by moving the logical_sector increment into the success path. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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4f354560 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Move read_seqcount_begin() into make_stripe_request() Now that prepare_to_wait() isn't in the way, move read_sequcount_begin() into make_stripe_request(). No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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1cdb5b41 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Drop the do_prepare flag in raid5_make_request() prepare_to_wait() can be reasonably called after schedule instead of setting a flag and preparing in the next loop iteration. This means that prepare_to_wait() will be called before read_seqcount_begin(), but there shouldn't be any reason that the order matters here. On the first iteration of the loop prepare_to_wait() is already called first. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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f4aec6a0 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Factor out helper from raid5_make_request() loop Factor out the inner loop of raid5_make_request() into it's own helper called make_stripe_request(). The helper returns a number of statuses: SUCCESS, RETRY, SCHEDULE_AND_RETRY and FAIL. This makes the code a bit easier to understand and allows the SCHEDULE_AND_RETRY path to be made common. A context structure is added to contain do_flush. It will be used more in subsequent patches for state that needs to be kept outside the loop. No functional changes intended. This will be cleaned up further in subsequent patches to untangle the gen_lock and do_prepare logic further. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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1baa1126 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Move common stripe get code into new find_get_stripe() helper Both uses of find_stripe() require a fairly complicated dance to increment the reference count. Move this into a common find_get_stripe() helper. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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8757fef6 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Move stripe_add_to_batch_list() call out of add_stripe_bio() stripe_add_to_batch_list() is better done in the loop in make_request instead of inside add_stripe_bio(). This is clearer and allows for storing the batch_head state outside the loop in a subsequent patch. The call to add_stripe_bio() in retry_aligned_read() is for read and batching only applies to write. So it's impossible for batching to happen at that call site. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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27fb7010 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Refactor raid5_make_request loop Break immediately if raid5_get_active_stripe() returns NULL and deindent the rest of the loop. Annotate this check with an unlikely(). This makes the code easier to read and reduces the indentation level. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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a8bb304c |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Factor out ahead_of_reshape() function There are a few uses of an ugly ternary operator in raid5_make_request() to check if a sector is a head of a reshape sector. Factor this out into a simple helper called ahead_of_reshape(). No functional changes intended. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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6e3f50d3 |
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16-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Make logic blocking check consistent with logic that blocks The check in raid5_make_request differs very slightly from the logic that causes it to block lower down. This likely does not cause a bug as the check is fuzzy anyway (as reshape may move on between the first check and the subsequent check). However, make it consistent so it can be cleaned up in a subsequent patch. The condition which causes the schedule is: !(mddev->reshape_backwards ? logical_sector < conf->reshape_progress : logical_sector >= conf->reshape_progress) && (mddev->reshape_backwards ? logical_sector < conf->reshape_safe : logical_sector >= conf->reshape_safe) The condition that causes the early bailout is made to match this. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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c629f345 |
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08-Jun-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: suspend the array for calls to log_exit() The raid5-cache code relies on there being no IO in flight when log_exit() is called. There are two places where this is not guaranteed so add mddev_suspend() and mddev_resume() calls to these sites. The site in raid5_change_consistency_policy() is in the error path, and another similar call site already has suspend/resume calls just below it; so it should be equally safe to make that change here. There is one remaining site in raid5_remove_disk() that we call log_exit() without suspending the array. Unfortunately, as the comment stated, we cannot call mddev_suspend from raid5d. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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a9010741 |
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14-Jul-2022 |
Bart Van Assche <bvanassche@acm.org> |
md/raid5: Use the enum req_op and blk_opf_t types Improve static type checking by using the enum req_op type for variables that represent a request operation and the new blk_opf_t type for variables that represent request flags. Acked-by: Song Liu <song@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220714180729.1065367-37-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
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5f7ef487 |
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18-Jul-2022 |
Dan Carpenter <dan.carpenter@oracle.com> |
md/raid5: missing error code in setup_conf() Return -ENOMEM if the allocation fails. Don't return success. Fixes: 8fbcba6b999b ("md/raid5: Cleanup setup_conf() error returns") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Song Liu <song@kernel.org>
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617b3658 |
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29-Jun-2022 |
Mikulas Patocka <mpatocka@redhat.com> |
dm raid: fix KASAN warning in raid5_add_disks There's a KASAN warning in raid5_add_disk when running the LVM testsuite. The warning happens in the test lvconvert-raid-reshape-linear_to_raid6-single-type.sh. We fix the warning by verifying that rdev->saved_raid_disk is within limits. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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1ebc2cec |
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29-Jun-2022 |
Mikulas Patocka <mpatocka@redhat.com> |
dm raid: fix KASAN warning in raid5_remove_disk There's a KASAN warning in raid5_remove_disk when running the LVM testsuite. We fix this warning by verifying that the "number" variable is within limits. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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913cce5a |
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12-May-2022 |
Christoph Hellwig <hch@lst.de> |
md: remove most calls to bdevname Use the %pg format specifier to save on stack consumption and code size. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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3d50d368 |
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17-Apr-2022 |
Christoph Hellwig <hch@lst.de> |
raid5: don't set the discard_alignment queue limit The discard_alignment queue limit is named a bit misleading means the offset into the block device at which the discard granularity starts. Setting it to the discard granularity as done by raid5 is mostly harmless but also useless. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220418045314.360785-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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4631f39f |
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07-Apr-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Annotate functions that hold device_lock with __must_hold A handful of functions note the device_lock must be held with a comment but this is not comprehensive. Many other functions hold the lock when taken so add an __must_hold() to each call to annotate when the lock is held. This makes it a bit easier to analyse device_lock. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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9aeb7f99 |
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07-Apr-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Annotate rdev/replacement access when mddev_lock is held The mddev_lock should be held during raid5_remove_disk() which is when the rdev/replacement pointers are modified. So any access to these pointers marked __rcu should be safe whenever the mddev_lock is held. There are numerous such access that currently produce sparse warnings. Add a helper function, rdev_mdlock_deref() that wraps rcu_dereference_protected() in all these instances. This annotation fixes a number of sparse warnings. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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e38b0432 |
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07-Apr-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Annotate rdev/replacement accesses when nr_pending is elevated There are a number of accesses to __rcu variables that should be safe because nr_pending in the disk is known to be elevated. Create a wrapper around rcu_dereference_protected() to annotate these accesses and verify that nr_pending is non-zero. This fixes a number of sparse warnings. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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#
b0920ede |
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07-Apr-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Add __rcu annotation to struct disk_info rdev and replacement are protected in some circumstances with rcu_dereference and synchronize_rcu (in raid5_remove_disk()). However, they were not annotated with __rcu so a sparse warning is emitted for every rcu_dereference() call. Add the __rcu annotation and fix up the initialization with RCU_INIT_POINTER, all pointer modifications with rcu_assign_pointer(), a few cases where the pointer value is tested with rcu_access_pointer() and one case where READ_ONCE() is used instead of rcu_dereference(), a case in print_raid5_conf() that should have rcu_dereference() and rcu_read_[un]lock() calls. Additional sparse issues will be fixed up in further commits. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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#
8fbcba6b |
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07-Apr-2022 |
Logan Gunthorpe <logang@deltatee.com> |
md/raid5: Cleanup setup_conf() error returns Be more careful about the error returns. Most errors in this function are actually ENOMEM, but it forcibly returns EIO if conf has been allocated. Instead return ret and ensure it is set appropriately before each goto abort. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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#
57668f0a |
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22-Mar-2022 |
Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com> |
raid5: introduce MD_BROKEN Raid456 module had allowed to achieve failed state. It was fixed by fb73b357fb9 ("raid5: block failing device if raid will be failed"). This fix introduces a bug, now if raid5 fails during IO, it may result with a hung task without completion. Faulty flag on the device is necessary to process all requests and is checked many times, mainly in analyze_stripe(). Allow to set faulty on drive again and set MD_BROKEN if raid is failed. As a result, this level is allowed to achieve failed state again, but communication with userspace (via -EBUSY status) will be preserved. This restores possibility to fail array via #mdadm --set-faulty command and will be fixed by additional verification on mdadm side. Reproduction steps: mdadm -CR imsm -e imsm -n 3 /dev/nvme[0-2]n1 mdadm -CR r5 -e imsm -l5 -n3 /dev/nvme[0-2]n1 --assume-clean mkfs.xfs /dev/md126 -f mount /dev/md126 /mnt/root/ fio --filename=/mnt/root/file --size=5GB --direct=1 --rw=randrw --bs=64k --ioengine=libaio --iodepth=64 --runtime=240 --numjobs=4 --time_based --group_reporting --name=throughput-test-job --eta-newline=1 & echo 1 > /sys/block/nvme2n1/device/device/remove echo 1 > /sys/block/nvme1n1/device/device/remove [ 1475.787779] Call Trace: [ 1475.793111] __schedule+0x2a6/0x700 [ 1475.799460] schedule+0x38/0xa0 [ 1475.805454] raid5_get_active_stripe+0x469/0x5f0 [raid456] [ 1475.813856] ? finish_wait+0x80/0x80 [ 1475.820332] raid5_make_request+0x180/0xb40 [raid456] [ 1475.828281] ? finish_wait+0x80/0x80 [ 1475.834727] ? finish_wait+0x80/0x80 [ 1475.841127] ? finish_wait+0x80/0x80 [ 1475.847480] md_handle_request+0x119/0x190 [ 1475.854390] md_make_request+0x8a/0x190 [ 1475.861041] generic_make_request+0xcf/0x310 [ 1475.868145] submit_bio+0x3c/0x160 [ 1475.874355] iomap_dio_submit_bio.isra.20+0x51/0x60 [ 1475.882070] iomap_dio_bio_actor+0x175/0x390 [ 1475.889149] iomap_apply+0xff/0x310 [ 1475.895447] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.902736] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.909974] iomap_dio_rw+0x2f2/0x490 [ 1475.916415] ? iomap_dio_bio_actor+0x390/0x390 [ 1475.923680] ? atime_needs_update+0x77/0xe0 [ 1475.930674] ? xfs_file_dio_aio_read+0x6b/0xe0 [xfs] [ 1475.938455] xfs_file_dio_aio_read+0x6b/0xe0 [xfs] [ 1475.946084] xfs_file_read_iter+0xba/0xd0 [xfs] [ 1475.953403] aio_read+0xd5/0x180 [ 1475.959395] ? _cond_resched+0x15/0x30 [ 1475.965907] io_submit_one+0x20b/0x3c0 [ 1475.972398] __x64_sys_io_submit+0xa2/0x180 [ 1475.979335] ? do_io_getevents+0x7c/0xc0 [ 1475.986009] do_syscall_64+0x5b/0x1a0 [ 1475.992419] entry_SYSCALL_64_after_hwframe+0x65/0xca [ 1476.000255] RIP: 0033:0x7f11fc27978d [ 1476.006631] Code: Bad RIP value. [ 1476.073251] INFO: task fio:3877 blocked for more than 120 seconds. Cc: stable@vger.kernel.org Fixes: fb73b357fb9 ("raid5: block failing device if raid will be failed") Reviewd-by: Xiao Ni <xni@redhat.com> Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com> Signed-off-by: Song Liu <song@kernel.org>
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#
70200574 |
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14-Apr-2022 |
Christoph Hellwig <hch@lst.de> |
block: remove QUEUE_FLAG_DISCARD Just use a non-zero max_discard_sectors as an indicator for discard support, similar to what is done for write zeroes. The only places where needs special attention is the RAID5 driver, which must clear discard support for security reasons by default, even if the default stacking rules would allow for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd] Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390] Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: David Sterba <dsterba@suse.com> [btrfs] Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
10f0d2a5 |
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14-Apr-2022 |
Christoph Hellwig <hch@lst.de> |
block: add a bdev_nonrot helper Add a helper to check the nonrot flag based on the block_device instead of having to poke into the block layer internal request_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: David Sterba <dsterba@suse.com> [btrfs] Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220415045258.199825-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
c75e707f |
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04-Mar-2022 |
Christoph Hellwig <hch@lst.de> |
block: remove the per-bio/request write hint With the NVMe support for this gone, there are no consumers of these hints left, so remove them. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220304175556.407719-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
10fa225c |
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09-Feb-2022 |
Christoph Hellwig <hch@lst.de> |
scsi: md: Remove WRITE_SAME support There are no more end-users of REQ_OP_WRITE_SAME left, so we can start deleting it. Link: https://lore.kernel.org/r/20220209082828.2629273-6-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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#
03a6b195 |
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28-Feb-2022 |
Christoph Hellwig <hch@lst.de> |
raid5: initialize the stripe_head embeeded bios as needed Use bio_init to initialize the bios when needed to the full state instead of a partial initialization plus later setting of dev and op and bio_reset. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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#
abfc426d |
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02-Feb-2022 |
Christoph Hellwig <hch@lst.de> |
block: pass a block_device to bio_clone_fast Pass a block_device to bio_clone_fast and __bio_clone_fast and give the functions more suitable names. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20220202160109.108149-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
a7c50c94 |
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24-Jan-2022 |
Christoph Hellwig <hch@lst.de> |
block: pass a block_device and opf to bio_reset Pass the block_device that we plan to use this bio for and the operation to bio_reset to optimize the assigment. A NULL block_device can be passed, both for the passthrough case on a raw request_queue and to temporarily avoid refactoring some nasty code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220124091107.642561-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
49add496 |
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24-Jan-2022 |
Christoph Hellwig <hch@lst.de> |
block: pass a block_device and opf to bio_init Pass the block_device that we plan to use this bio for and the operation to bio_init to optimize the assignment. A NULL block_device can be passed, both for the passthrough case on a raw request_queue and to temporarily avoid refactoring some nasty code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220124091107.642561-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
0c031fd3 |
|
10-Dec-2021 |
Xiao Ni <xni@redhat.com> |
md: Move alloc/free acct bioset in to personality bioset acct is only needed for raid0 and raid5. Therefore, md_run only allocates it for raid0 and raid5. However, this does not cover personality takeover, which may cause uninitialized bioset. For example, the following repro steps: mdadm -CR /dev/md0 -l1 -n2 /dev/loop0 /dev/loop1 mdadm --wait /dev/md0 mkfs.xfs /dev/md0 mdadm /dev/md0 --grow -l5 mount /dev/md0 /mnt causes panic like: [ 225.933939] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 225.934903] #PF: supervisor instruction fetch in kernel mode [ 225.935639] #PF: error_code(0x0010) - not-present page [ 225.936361] PGD 0 P4D 0 [ 225.936677] Oops: 0010 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN PTI [ 225.937525] CPU: 27 PID: 1133 Comm: mount Not tainted 5.16.0-rc3+ #706 [ 225.938416] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.module_el8.4.0+547+a85d02ba 04/01/2014 [ 225.939922] RIP: 0010:0x0 [ 225.940289] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. [ 225.941196] RSP: 0018:ffff88815897eff0 EFLAGS: 00010246 [ 225.941897] RAX: 0000000000000000 RBX: 0000000000092800 RCX: ffffffff81370a39 [ 225.942813] RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000092800 [ 225.943772] RBP: 1ffff1102b12fe04 R08: fffffbfff0b43c01 R09: fffffbfff0b43c01 [ 225.944807] R10: ffffffff85a1e007 R11: fffffbfff0b43c00 R12: ffff88810eaaaf58 [ 225.945757] R13: 0000000000000000 R14: ffff88810eaaafb8 R15: ffff88815897f040 [ 225.946709] FS: 00007ff3f2505080(0000) GS:ffff888fb5e00000(0000) knlGS:0000000000000000 [ 225.947814] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 225.948556] CR2: ffffffffffffffd6 CR3: 000000015aa5a006 CR4: 0000000000370ee0 [ 225.949537] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 225.950455] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 225.951414] Call Trace: [ 225.951787] <TASK> [ 225.952120] mempool_alloc+0xe5/0x250 [ 225.952625] ? mempool_resize+0x370/0x370 [ 225.953187] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.953862] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.954464] ? sched_clock_cpu+0x15/0x120 [ 225.955019] ? find_held_lock+0xac/0xd0 [ 225.955564] bio_alloc_bioset+0x1ed/0x2a0 [ 225.956080] ? lock_downgrade+0x3a0/0x3a0 [ 225.956644] ? bvec_alloc+0xc0/0xc0 [ 225.957135] bio_clone_fast+0x19/0x80 [ 225.957651] raid5_make_request+0x1370/0x1b70 [ 225.958286] ? sched_clock_cpu+0x15/0x120 [ 225.958797] ? __lock_acquire+0x8b2/0x3510 [ 225.959339] ? raid5_get_active_stripe+0xce0/0xce0 [ 225.959986] ? lock_is_held_type+0xd8/0x130 [ 225.960528] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 225.961135] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 225.961703] ? sched_clock_cpu+0x15/0x120 [ 225.962232] ? lock_release+0x27a/0x6c0 [ 225.962746] ? do_wait_intr_irq+0x130/0x130 [ 225.963302] ? lock_downgrade+0x3a0/0x3a0 [ 225.963815] ? lock_release+0x6c0/0x6c0 [ 225.964348] md_handle_request+0x342/0x530 [ 225.964888] ? set_in_sync+0x170/0x170 [ 225.965397] ? blk_queue_split+0x133/0x150 [ 225.965988] ? __blk_queue_split+0x8b0/0x8b0 [ 225.966524] ? submit_bio_checks+0x3b2/0x9d0 [ 225.967069] md_submit_bio+0x127/0x1c0 [...] Fix this by moving alloc/free of acct bioset to pers->run and pers->free. While we are on this, properly handle md_integrity_register() error in raid0_run(). Fixes: daee2024715d (md: check level before create and exit io_acct_set) Cc: stable@vger.kernel.org Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org>
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#
bf2c411b |
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21-Dec-2021 |
Vishal Verma <vverma@digitalocean.com> |
md: raid456 add nowait support Returns EAGAIN in case the raid456 driver would block waiting for reshape. Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Vishal Verma <vverma@digitalocean.com> Signed-off-by: Song Liu <song@kernel.org>
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#
770b1d21 |
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15-Nov-2021 |
Davidlohr Bueso <dave@stgolabs.net> |
md/raid5: play nice with PREEMPT_RT raid_run_ops() relies on the implicitly disabled preemption for its percpu ops, although this is really about CPU locality. This breaks RT semantics as it can take regular (and thus sleeping) spinlocks, such as stripe_lock. Add a local_lock such that non-RT does not change and continues to be just map to preempt_disable/enable, but makes RT happy as the region will use a per-CPU spinlock and thus be preemptible and still guarantee CPU locality. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
54679486 |
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04-Oct-2021 |
Guoqing Jiang <guoqing.jiang@linux.dev> |
md: remove unused argument from md_new_event Actually, mddev is not used by md_new_event. Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
c6efe434 |
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04-Oct-2021 |
Guoqing Jiang <guoqing.jiang@linux.dev> |
md/raid5: call roundup_pow_of_two in raid5_run Let's call roundup_pow_of_two here instead of open code. Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
252034e0 |
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03-Aug-2021 |
Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
md/raid5: Replace deprecated CPU-hotplug functions. The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20210803141621.780504-16-bigeasy@linutronix.de
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#
97ae2725 |
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07-Jun-2021 |
Gal Ofri <gal.ofri@storing.io> |
md/raid5: avoid device_lock in read_one_chunk() There is a lock contention on device_lock in read_one_chunk(). device_lock is taken to sync conf->active_aligned_reads and conf->quiesce. read_one_chunk() takes the lock, then waits for quiesce=0 (resumed) before incrementing active_aligned_reads. raid5_quiesce() takes the lock, sets quiesce=2 (in-progress), then waits for active_aligned_reads to be zero before setting quiesce=1 (suspended). Introduce a fast (lockless) path in read_one_chunk(): activate aligned read without taking device_lock. In case quiesce starts while activating the aligned-read in fast path, deactivate it and revert to old behavior (take device_lock and wait for quiesce to finish). Add smp store/load in raid5_quiesce()/read_one_chunk() respectively to gaurantee that read_one_chunk() does not miss an ongoing quiesce. My setups: 1. 8 local nvme drives (each up to 250k iops). 2. 8 ram disks (brd). Each setup with raid6 (6+2), 1024 io threads on a 96 cpu-cores (48 per socket) system. Record both iops and cpu spent on this contention with rand-read-4k. Record bw with sequential-read-128k. Note: in most cases cpu is still busy but due to "new" bottlenecks. nvme: | iops | cpu | bw ----------------------------------------------- without patch | 1.6M | ~50% | 5.5GB/s with patch | 2M (throttled) | 0% | 16GB/s (throttled) ram (brd): | iops | cpu | bw ----------------------------------------------- without patch | 2M | ~80% | 24GB/s with patch | 4M | 0% | 55GB/s CC: Song Liu <song@kernel.org> CC: Neil Brown <neilb@suse.de> Reviewed-by: NeilBrown <neilb@suse.de> Signed-off-by: Gal Ofri <gal.ofri@storing.io> Signed-off-by: Song Liu <song@kernel.org>
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#
c32dc040 |
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28-May-2021 |
Rikard Falkeborn <rikard.falkeborn@gmail.com> |
md: Constify attribute_group structs The attribute_group structs are never modified, they're only passed to sysfs_create_group() and sysfs_remove_group(). Make them const to allow the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: Song Liu <song@kernel.org>
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#
1147f58e |
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25-May-2021 |
Guoqing Jiang <jgq516@gmail.com> |
md/raid5: avoid redundant bio clone in raid5_read_one_chunk After enable io accounting, chunk read bio could be cloned twice which is not good. To avoid such inefficiency, let's clone align_bio from io_acct_set too, then we need only call md_account_bio in make_request unconditionally. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
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#
c82aa1b7 |
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25-May-2021 |
Guoqing Jiang <jgq516@gmail.com> |
md/raid5: move checking badblock before clone bio in raid5_read_one_chunk We don't need to clone bio if the relevant region has badblock. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
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#
10764815 |
|
25-May-2021 |
Guoqing Jiang <jgq516@gmail.com> |
md: add io accounting for raid0 and raid5 We introduce a new bioset (io_acct_set) for raid0 and raid5 since they don't own clone infrastructure to accounting io. And the bioset is added to mddev instead of to raid0 and raid5 layer, because with this way, we can put common functions to md.h and reuse them in raid0 and raid5. Also struct md_io_acct is added accordingly which includes io start_time, the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct to get related io status. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Song Liu <song@kernel.org>
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#
cc146267 |
|
19-May-2021 |
Christoph Hellwig <hch@lst.de> |
md/raid5: remove an incorrect assert in in_chunk_boundary Now that the original bdev is stored in the bio this assert is incorrect and will trigger for any partitioned raid5 device. Reported-by: Florian Dazinger <spam02@dazinger.net> Tested-by: Florian Dazinger <spam02@dazinger.net> Cc: stable@vger.kernel.org # 5.12 Fixes: 309dca309fc3 ("block: store a block_device pointer in struct bio"), Reviewed-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <song@kernel.org>
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#
4f0f586b |
|
08-Apr-2021 |
Sami Tolvanen <samitolvanen@google.com> |
treewide: Change list_sort to use const pointers list_sort() internally casts the comparison function passed to it to a different type with constant struct list_head pointers, and uses this pointer to call the functions, which trips indirect call Control-Flow Integrity (CFI) checking. Instead of removing the consts, this change defines the list_cmp_func_t type and changes the comparison function types of all list_sort() callers to use const pointers, thus avoiding type mismatches. Suggested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com
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#
c5eec74f |
|
15-Dec-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
md/raid5: cast chunk_sectors to sector_t value Currently, raid5 calculates dev_sectors from chunk_sectors without proper cast, which is problematic. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
e82ed3a4 |
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26-Jan-2021 |
Christoph Hellwig <hch@lst.de> |
md/raid6: refactor raid5_read_one_chunk Refactor raid5_read_one_chunk so that all simple checks are done before allocating the bio. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
309dca30 |
|
24-Jan-2021 |
Christoph Hellwig <hch@lst.de> |
block: store a block_device pointer in struct bio Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
1c02fca6 |
|
03-Dec-2020 |
Christoph Hellwig <hch@lst.de> |
block: remove the request_queue argument to the block_bio_remap tracepoint The request_queue can trivially be derived from the bio. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
b44c018c |
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05-Oct-2020 |
Song Liu <songliubraving@fb.com> |
md/raid5: fix oops during stripe resizing KoWei reported crash during raid5 reshape: [ 1032.252932] Oops: 0002 [#1] SMP PTI [...] [ 1032.252943] RIP: 0010:memcpy_erms+0x6/0x10 [...] [ 1032.252947] RSP: 0018:ffffba1ac0c03b78 EFLAGS: 00010286 [ 1032.252949] RAX: 0000784ac0000000 RBX: ffff91bec3d09740 RCX: 0000000000001000 [ 1032.252951] RDX: 0000000000001000 RSI: ffff91be6781c000 RDI: 0000784ac0000000 [ 1032.252953] RBP: ffffba1ac0c03bd8 R08: 0000000000001000 R09: ffffba1ac0c03bf8 [ 1032.252954] R10: 0000000000000000 R11: 0000000000000000 R12: ffffba1ac0c03bf8 [ 1032.252955] R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000 [ 1032.252958] FS: 0000000000000000(0000) GS:ffff91becf500000(0000) knlGS:0000000000000000 [ 1032.252959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1032.252961] CR2: 0000784ac0000000 CR3: 000000031780a002 CR4: 00000000001606e0 [ 1032.252962] Call Trace: [ 1032.252969] ? async_memcpy+0x179/0x1000 [async_memcpy] [ 1032.252977] ? raid5_release_stripe+0x8e/0x110 [raid456] [ 1032.252982] handle_stripe_expansion+0x15a/0x1f0 [raid456] [ 1032.252988] handle_stripe+0x592/0x1270 [raid456] [ 1032.252993] handle_active_stripes.isra.0+0x3cb/0x5a0 [raid456] [ 1032.252999] raid5d+0x35c/0x550 [raid456] [ 1032.253002] ? schedule+0x42/0xb0 [ 1032.253006] ? schedule_timeout+0x10e/0x160 [ 1032.253011] md_thread+0x97/0x160 [ 1032.253015] ? wait_woken+0x80/0x80 [ 1032.253019] kthread+0x104/0x140 [ 1032.253022] ? md_start_sync+0x60/0x60 [ 1032.253024] ? kthread_park+0x90/0x90 [ 1032.253027] ret_from_fork+0x35/0x40 This is because cache_size_mutex was unlocked too early in resize_stripes, which races with grow_one_stripe() that grow_one_stripe() allocates a stripe with wrong pool_size. Fix this issue by unlocking cache_size_mutex after updating pool_size. Cc: <stable@vger.kernel.org> # v4.4+ Reported-by: KoWei Sung <winders@amazon.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
38912584 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: reallocate page array after setting new stripe_size When try to resize stripe_size, we also need to free old shared page array and allocate new. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
f16acaf3 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: resize stripe_head when reshape array When reshape array, we try to reuse shared pages of old stripe_head, and allocate more for the new one if needed. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
046169f0 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: let multiple devices of stripe_head share page In current implementation, grow_buffers() uses alloc_page() to allocate the buffers for each stripe_head, i.e. allocate a page for each dev[i] in stripe_head. After setting stripe_size as a configurable value by writing sysfs entry, it means that we always allocate 64K buffers, but just use 4K of them when stripe_size is 4K in 64KB arm64. To avoid wasting memory, we try to let multiple sh->dev share one real page. That means, multiple sh->dev[i].page will point to the only page with different offset. Example of 64K PAGE_SIZE and 4K stripe_size as following: 64K PAGE_SIZE +---+---+---+---+------------------------------+ | | | | | | | | | | +-+-+-+-+-+-+-+-+------------------------------+ ^ ^ ^ ^ | | | +----------------------------+ | | | | | | +-------------------+ | | | | | | +----------+ | | | | | | +-+ | | | | | | | +-----+-----+------+-----+------+-----+------+------+ sh | offset(0) | offset(4K) | offset(8K) | offset(12K) | + +-----------+------------+------------+-------------+ +----> dev[0].page dev[1].page dev[2].page dev[3].page A new 'pages' array will be added into stripe_head to record shared page used by this stripe_head. Allocate them when grow_buffers() and free them when shrink_buffers(). After trying to share page, the users of sh->dev[i].page need to take care of the related page offset: page of issued bio and page passed to xor compution functions. But thanks for previous different page offset supported. Here, we just need to set correct dev[i].offset. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
4f86ff55 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid6: let async recovery function support different page offset For now, asynchronous raid6 recovery calculate functions are require common offset for pages. But, we expect them to support different page offset after introducing stripe shared page. Do that by simplily adding page offset where each page address are referred. Then, replace the old interface with the new ones in raid6 and raid6test. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
d69454bc |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid6: let syndrome computor support different page offset For now, syndrome compute functions require common offset in the pages array. However, we expect them to support different offset when try to use shared page in the following. Simplily covert them by adding page offset where each page address are referred. Since the only caller of async_gen_syndrome() and async_syndrome_val() are in raid6, we don't want to reserve the old interface but modify the interface directly. After that, replacing old interfaces with new ones for raid6 and raid6test. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
a7c224a8 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: convert to new xor compution interface We try to replace async_xor() and async_xor_val() with the new introduced interface async_xor_offs() and async_xor_val_offs() for raid456. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
248728dd |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: make async_copy_data() to support different page offset ops_run_biofill() and ops_run_biodrain() will call async_copy_data() to copy sh->dev[i].page from or to bio page. For now, it implies the offset of dev[i].page is 0. But we want to support different page offset in the following. Thus, pass page offset to these functions and replace 'page_offset' with 'page_offset + poff'. No functional change. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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7aba13b7 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: add a new member of offset into r5dev Add a new member of offset into struct r5dev. It indicates the offset of related dev[i].page. For now, since each device have a privated page, the value is always 0. Thus, we set offset as 0 when allcate page in grow_buffers() and resize_stripes(). To support following different page offset, we try to use the page offset rather than '0' directly for async_memcpy() and ops_run_io(). We try to support different page offset for xor compution functions in the following. To avoid repeatly allocate a new array each time, we add a memory region into scribble buffer to record offset. No functional change. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
1cb039f3 |
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24-Sep-2020 |
Christoph Hellwig <hch@lst.de> |
bdi: replace BDI_CAP_STABLE_WRITES with a queue and a sb flag The BDI_CAP_STABLE_WRITES is one of the few bits of information in the backing_dev_info shared between the block drivers and the writeback code. To help untangling the dependency replace it with a queue flag and a superblock flag derived from it. This also helps with the case of e.g. a file system requiring stable writes due to its own checksumming, but not forcing it on other users of the block device like the swap code. One downside is that we an't support the stable_pages_required bdi attribute in sysfs anymore. It is replaced with a queue attribute which also is writable for easier testing. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
c2e4cd57 |
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24-Sep-2020 |
Christoph Hellwig <hch@lst.de> |
block: lift setting the readahead size into the block layer Drivers shouldn't really mess with the readahead size, as that is a VM concept. Instead set it based on the optimal I/O size by lifting the algorithm from the md driver when registering the disk. Also set bdi->io_pages there as well by applying the same scheme based on max_sectors. To ensure the limits work well for stacking drivers a new helper is added to update the readahead limits from the block limits, which is also called from disk_stack_limits. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
16ef5101 |
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24-Sep-2020 |
Christoph Hellwig <hch@lst.de> |
md: update the optimal I/O size on reshape The raid5 and raid10 drivers currently update the read-ahead size, but not the optimal I/O size on reshape. To prepare for deriving the read-ahead size from the optimal I/O size make sure it is updated as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
6af10a33 |
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20-Aug-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: make sure stripe_size as power of two Commit 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") make stripe_size as a configurable value. It just requires stripe_size as multiple of 4KB. In fact, we should make sure stripe_size as power of two. Otherwise, stripe_shift which is the result of ilog2 can not represent the real stripe_size. Then, stripe_hash() and stripe_hash_locks_hash() may get unexpected value. Fixes: 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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df561f66 |
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23-Aug-2020 |
Gustavo A. R. Silva <gustavoars@kernel.org> |
treewide: Use fallthrough pseudo-keyword Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
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#
45a4d8fd |
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31-Jul-2020 |
ChangSyun Peng <allenpeng@synology.com> |
md/raid5: Allow degraded raid6 to do rmw Degraded raid6 always do reconstruct-write now. With raid6 xor supported, we can do rmw in degraded raid6. This patch can reduce many read IOs to improve performance. If the failed disk is P, Q or the disk we want to write to, we may need to do reconstruct-write in max degraded raid6. In this situation we can not read enough data from handle_stripe_dirtying() so we have to set force_rcw in handle_stripe_fill() to read all data. Reviewed-by: Alex Wu <alexwu@synology.com> Reviewed-by: BingJing Chang <bingjingc@synology.com> Reviewed-by: Danny Shih <dannyshih@synology.com> Signed-off-by: ChangSyun Peng <allenpeng@synology.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
a1c6ae3d |
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31-Jul-2020 |
ChangSyun Peng <allenpeng@synology.com> |
md/raid5: Fix Force reconstruct-write io stuck in degraded raid5 In degraded raid5, we need to read parity to do reconstruct-write when data disks fail. However, we can not read parity from handle_stripe_dirtying() in force reconstruct-write mode. Reproducible Steps: 1. Create degraded raid5 mdadm -C /dev/md2 --assume-clean -l5 -n3 /dev/sda2 /dev/sdb2 missing 2. Set rmw_level to 0 echo 0 > /sys/block/md2/md/rmw_level 3. IO to raid5 Now some io may be stuck in raid5. We can use handle_stripe_fill() to read the parity in this situation. Cc: <stable@vger.kernel.org> # v4.4+ Reviewed-by: Alex Wu <alexwu@synology.com> Reviewed-by: BingJing Chang <bingjingc@synology.com> Reviewed-by: Danny Shih <dannyshih@synology.com> Signed-off-by: ChangSyun Peng <allenpeng@synology.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
3a31cf3d |
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27-Jul-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: don't duplicate code for different paths in handle_stripe As we can see, R5_LOCKED is set and s.locked is increased whether R5_ReWrite is set or not, so move it to common path. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
e3914d59 |
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27-Jul-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
md/raid5: remove the redundant setting of STRIPE_HANDLE The flag is already set before compare rcw with rmw, so it is not necessary to do it again. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
0a87b25f |
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20-Jul-2020 |
Ahmed S. Darwish <a.darwish@linutronix.de> |
raid5: Use sequence counter with associated spinlock A sequence counter write side critical section must be protected by some form of locking to serialize writers. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_spinlock_t data type, which allows to associate a spinlock with the sequence counter. This enables lockdep to verify that the spinlock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Song Liu <song@kernel.org> Link: https://lkml.kernel.org/r/20200720155530.1173732-20-a.darwish@linutronix.de
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#
83c3e5e1 |
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22-Jul-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: use do_div() for 64 bit divisions in raid5_sync_request We get compilation error on 32-bit architectures (e.g. m68k), as: ERROR: modpost: "__udivdi3" [drivers/md/raid456.ko] undefined! Since 'sync_blocks' is defined as u64, use do_div() to fix this error. Fixes: c911c46c017c ("md/raid456: convert macro STRIPE_* to RAID5_STRIPE_*") Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
3b5408b9 |
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18-Jul-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: support config stripe_size by sysfs entry Adding a new 'stripe_size' sysfs entry to set and show stripe_size. stripe_size should not be bigger than PAGE_SIZE, and it requires to be multiple of 4096. We can adjust stripe_size by writing value into sysfs entry, likely, set stripe_size as 16KB: echo 16384 > /sys/block/md1/md/stripe_size Show current stripe_size value: cat /sys/block/md1/md/stripe_size For PAGE_SIZE is equal to 4096, 'stripe_size' can just be read. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
e2368582 |
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18-Jul-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid5: set default stripe_size as 4096 In RAID5, if issued bio size is bigger than stripe_size, it will be split in the unit of stripe_size and process them one by one. Even for size less then stripe_size, RAID5 also request data from disk at least of stripe_size. Nowdays, stripe_size is equal to the value of PAGE_SIZE. Since filesystem usually issue bio in the unit of 4KB, there is no problem for PAGE_SIZE as 4KB. But, for 64KB PAGE_SIZE, bio from filesystem requests 4KB data while RAID5 issue IO at least stripe_size (64KB) each time. That will waste resource of disk bandwidth and compute xor. To avoding the waste, we want to make stripe_size configurable. This patch just set default stripe_size as 4096. User can also set the value bigger than 4KB for some special requirements, such as we know the issued io size is more than 4KB. To evaluate the new feature, we create raid5 device '/dev/md5' with 4 SSD disk and test it on arm64 machine with 64KB PAGE_SIZE. 1) We format /dev/md5 with mkfs.ext4 and mount ext4 with default configure on /mnt directory. Then, trying to test it by dbench with command: dbench -D /mnt -t 1000 10. Result show as: 'stripe_size = 64KB' Operation Count AvgLat MaxLat ---------------------------------------- NTCreateX 9805011 0.021 64.728 Close 7202525 0.001 0.120 Rename 415213 0.051 44.681 Unlink 1980066 0.079 93.147 Deltree 240 1.793 6.516 Mkdir 120 0.004 0.007 Qpathinfo 8887512 0.007 37.114 Qfileinfo 1557262 0.001 0.030 Qfsinfo 1629582 0.012 0.152 Sfileinfo 798756 0.040 57.641 Find 3436004 0.019 57.782 WriteX 4887239 0.021 57.638 ReadX 15370483 0.005 37.818 LockX 31934 0.003 0.022 UnlockX 31933 0.001 0.021 Flush 687205 13.302 530.088 Throughput 307.799 MB/sec 10 clients 10 procs max_latency=530.091 ms ------------------------------------------------------- 'stripe_size = 4KB' Operation Count AvgLat MaxLat ---------------------------------------- NTCreateX 11999166 0.021 36.380 Close 8814128 0.001 0.122 Rename 508113 0.051 29.169 Unlink 2423242 0.070 38.141 Deltree 300 1.885 7.155 Mkdir 150 0.004 0.006 Qpathinfo 10875921 0.007 35.485 Qfileinfo 1905837 0.001 0.032 Qfsinfo 1994304 0.012 0.125 Sfileinfo 977450 0.029 26.489 Find 4204952 0.019 9.361 WriteX 5981890 0.019 27.804 ReadX 18809742 0.004 33.491 LockX 39074 0.003 0.025 UnlockX 39074 0.001 0.014 Flush 841022 10.712 458.848 Throughput 376.777 MB/sec 10 clients 10 procs max_latency=458.852 ms ------------------------------------------------------- It show that setting stripe_size as 4KB has higher thoughput, i.e. (376.777 vs 307.799) and has smaller latency than that setting as 64KB. 2) We try to evaluate IO throughput for /dev/md5 by fio with config: [4KB randwrite] direct=1 numjob=2 iodepth=64 ioengine=libaio filename=/dev/md5 bs=4KB rw=randwrite [64KB write] direct=1 numjob=2 iodepth=64 ioengine=libaio filename=/dev/md5 bs=1MB rw=write The result as follow: + + | stripe_size(64KB) | stripe_size(4KB) +----------------------------------------------------+ 4KB randwrite | 15MB/s | 100MB/s +----------------------------------------------------+ 1MB write | 1000MB/s | 700MB/s The result show that when size of io is bigger than 4KB (64KB), 64KB stripe_size has much higher IOPS. But for 4KB randwrite, that means, size of io issued to device are smaller, 4KB stripe_size have better performance. Normally, default value (4096) can get relatively good performance. But if each issued io is bigger than 4096, setting value more than 4096 may get better performance. Here, we just set default stripe_size as 4096, and we will try to support setting different stripe_size by sysfs interface in the following patch. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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c911c46c |
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18-Jul-2020 |
Yufen Yu <yuyufen@huawei.com> |
md/raid456: convert macro STRIPE_* to RAID5_STRIPE_* Convert macro STRIPE_SIZE, STRIPE_SECTORS and STRIPE_SHIFT to RAID5_STRIPE_SIZE(), RAID5_STRIPE_SECTORS() and RAID5_STRIPE_SHIFT(). This patch is prepare for the following adjustable stripe_size. It will not change any existing functionality. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
3f649ab7 |
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03-Jun-2020 |
Kees Cook <keescook@chromium.org> |
treewide: Remove uninitialized_var() usage Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>
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1684e975 |
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16-Jun-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: remove the meaningless check in raid5_make_request We can't guarntee the batched stripe to be set with STRIPE_HANDLE since there are lots of functions could set the flag, such as sync_request, ops_complete_* and end_{read,write}_request etc. Also clear_batch_ready called in handle_stripe ensures the batched list can't continue to be handled by handle_stripe. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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cb9902db |
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16-Jun-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: put the comment of clear_batch_ready to the right place To make people understand the function well, let's put the comment to the right place. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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a377a472 |
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16-Jun-2020 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: call clear_batch_ready before set STRIPE_ACTIVE We tried to only put the head sh of batch list to handle_list, then the handle_stripe doesn't handle other members in the batch list. However, we still got the calltrace in break_stripe_batch_list. [593764.644269] stripe state: 2003 kernel: [593764.644299] ------------[ cut here ]------------ kernel: [593764.644308] WARNING: CPU: 12 PID: 856 at drivers/md/raid5.c:4625 break_stripe_batch_list+0x203/0x240 [raid456] [...] kernel: [593764.644363] Call Trace: kernel: [593764.644370] handle_stripe+0x907/0x20c0 [raid456] kernel: [593764.644376] ? __wake_up_common_lock+0x89/0xc0 kernel: [593764.644379] handle_active_stripes.isra.57+0x35f/0x570 [raid456] kernel: [593764.644382] ? raid5_wakeup_stripe_thread+0x96/0x1f0 [raid456] kernel: [593764.644385] raid5d+0x480/0x6a0 [raid456] kernel: [593764.644390] ? md_thread+0x11f/0x160 kernel: [593764.644392] md_thread+0x11f/0x160 kernel: [593764.644394] ? wait_woken+0x80/0x80 kernel: [593764.644396] kthread+0xfc/0x130 kernel: [593764.644398] ? find_pers+0x70/0x70 kernel: [593764.644399] ? kthread_create_on_node+0x70/0x70 kernel: [593764.644401] ret_from_fork+0x1f/0x30 As we can see, the stripe was set with STRIPE_ACTIVE and STRIPE_HANDLE, and only handle_stripe could set those flags then return. And since the stipe was already in the batch list, we need to return earlier before set the two flags. And after dig a little about git history especially commit 3664847d95e6 ("md/raid5: fix a race condition in stripe batch"), it seems the batched stipe still could be handled by handle_stipe, then handle_stipe needs to return earlier if clear_batch_ready to return true. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
2aada5b1 |
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15-Jul-2020 |
Damien Le Moal <damien.lemoal@wdc.com> |
md: raid5: Fix compilation warning Remove the if statement around the calls to sysfs_link_rdev() to avoid the compilation warning "suggest braces around empty body in an ‘if’ statement" when compiling with W=1. Also fix function description comments to avoid kdoc format warnings. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
e1a86dbb |
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14-Jul-2020 |
Junxiao Bi <junxiao.bi@oracle.com> |
md: fix deadlock causing by sysfs_notify The following deadlock was captured. The first process is holding 'kernfs_mutex' and hung by io. The io was staging in 'r1conf.pending_bio_list' of raid1 device, this pending bio list would be flushed by second process 'md127_raid1', but it was hung by 'kernfs_mutex'. Using sysfs_notify_dirent_safe() to replace sysfs_notify() can fix it. There were other sysfs_notify() invoked from io path, removed all of them. PID: 40430 TASK: ffff8ee9c8c65c40 CPU: 29 COMMAND: "probe_file" #0 [ffffb87c4df37260] __schedule at ffffffff9a8678ec #1 [ffffb87c4df372f8] schedule at ffffffff9a867f06 #2 [ffffb87c4df37310] io_schedule at ffffffff9a0c73e6 #3 [ffffb87c4df37328] __dta___xfs_iunpin_wait_3443 at ffffffffc03a4057 [xfs] #4 [ffffb87c4df373a0] xfs_iunpin_wait at ffffffffc03a6c79 [xfs] #5 [ffffb87c4df373b0] __dta_xfs_reclaim_inode_3357 at ffffffffc039a46c [xfs] #6 [ffffb87c4df37400] xfs_reclaim_inodes_ag at ffffffffc039a8b6 [xfs] #7 [ffffb87c4df37590] xfs_reclaim_inodes_nr at ffffffffc039bb33 [xfs] #8 [ffffb87c4df375b0] xfs_fs_free_cached_objects at ffffffffc03af0e9 [xfs] #9 [ffffb87c4df375c0] super_cache_scan at ffffffff9a287ec7 #10 [ffffb87c4df37618] shrink_slab at ffffffff9a1efd93 #11 [ffffb87c4df37700] shrink_node at ffffffff9a1f5968 #12 [ffffb87c4df37788] do_try_to_free_pages at ffffffff9a1f5ea2 #13 [ffffb87c4df377f0] try_to_free_mem_cgroup_pages at ffffffff9a1f6445 #14 [ffffb87c4df37880] try_charge at ffffffff9a26cc5f #15 [ffffb87c4df37920] memcg_kmem_charge_memcg at ffffffff9a270f6a #16 [ffffb87c4df37958] new_slab at ffffffff9a251430 #17 [ffffb87c4df379c0] ___slab_alloc at ffffffff9a251c85 #18 [ffffb87c4df37a80] __slab_alloc at ffffffff9a25635d #19 [ffffb87c4df37ac0] kmem_cache_alloc at ffffffff9a251f89 #20 [ffffb87c4df37b00] alloc_inode at ffffffff9a2a2b10 #21 [ffffb87c4df37b20] iget_locked at ffffffff9a2a4854 #22 [ffffb87c4df37b60] kernfs_get_inode at ffffffff9a311377 #23 [ffffb87c4df37b80] kernfs_iop_lookup at ffffffff9a311e2b #24 [ffffb87c4df37ba8] lookup_slow at ffffffff9a290118 #25 [ffffb87c4df37c10] walk_component at ffffffff9a291e83 #26 [ffffb87c4df37c78] path_lookupat at ffffffff9a293619 #27 [ffffb87c4df37cd8] filename_lookup at ffffffff9a2953af #28 [ffffb87c4df37de8] user_path_at_empty at ffffffff9a295566 #29 [ffffb87c4df37e10] vfs_statx at ffffffff9a289787 #30 [ffffb87c4df37e70] SYSC_newlstat at ffffffff9a289d5d #31 [ffffb87c4df37f18] sys_newlstat at ffffffff9a28a60e #32 [ffffb87c4df37f28] do_syscall_64 at ffffffff9a003949 #33 [ffffb87c4df37f50] entry_SYSCALL_64_after_hwframe at ffffffff9aa001ad RIP: 00007f617a5f2905 RSP: 00007f607334f838 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 00007f6064044b20 RCX: 00007f617a5f2905 RDX: 00007f6064044b20 RSI: 00007f6064044b20 RDI: 00007f6064005890 RBP: 00007f6064044aa0 R8: 0000000000000030 R9: 000000000000011c R10: 0000000000000013 R11: 0000000000000246 R12: 00007f606417e6d0 R13: 00007f6064044aa0 R14: 00007f6064044b10 R15: 00000000ffffffff ORIG_RAX: 0000000000000006 CS: 0033 SS: 002b PID: 927 TASK: ffff8f15ac5dbd80 CPU: 42 COMMAND: "md127_raid1" #0 [ffffb87c4df07b28] __schedule at ffffffff9a8678ec #1 [ffffb87c4df07bc0] schedule at ffffffff9a867f06 #2 [ffffb87c4df07bd8] schedule_preempt_disabled at ffffffff9a86825e #3 [ffffb87c4df07be8] __mutex_lock at ffffffff9a869bcc #4 [ffffb87c4df07ca0] __mutex_lock_slowpath at ffffffff9a86a013 #5 [ffffb87c4df07cb0] mutex_lock at ffffffff9a86a04f #6 [ffffb87c4df07cc8] kernfs_find_and_get_ns at ffffffff9a311d83 #7 [ffffb87c4df07cf0] sysfs_notify at ffffffff9a314b3a #8 [ffffb87c4df07d18] md_update_sb at ffffffff9a688696 #9 [ffffb87c4df07d98] md_update_sb at ffffffff9a6886d5 #10 [ffffb87c4df07da8] md_check_recovery at ffffffff9a68ad9c #11 [ffffb87c4df07dd0] raid1d at ffffffffc01f0375 [raid1] #12 [ffffb87c4df07ea0] md_thread at ffffffff9a680348 #13 [ffffb87c4df07f08] kthread at ffffffff9a0b8005 #14 [ffffb87c4df07f50] ret_from_fork at ffffffff9aa00344 Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
21cf8661 |
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01-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
writeback: remove bdi->congested_fn Except for pktdvd, the only places setting congested bits are file systems that allocate their own backing_dev_info structures. And pktdvd is a deprecated driver that isn't useful in stack setup either. So remove the dead congested_fn stacking infrastructure. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Acked-by: David Sterba <dsterba@suse.com> [axboe: fixup unused variables in bcache/request.c] Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
ed00aabd |
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01-Jul-2020 |
Christoph Hellwig <hch@lst.de> |
block: rename generic_make_request to submit_bio_noacct generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
7f8a30e5 |
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09-Apr-2020 |
Coly Li <colyli@suse.de> |
raid5: update code comment of scribble_alloc() Code comments of scribble_alloc() is outdated for a while. This patch update the comments in function header for the new parameter list. Suggested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
ba54d4d4 |
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09-Apr-2020 |
Coly Li <colyli@suse.de> |
raid5: remove gfp flags from scribble_alloc() Using GFP_NOIO flag to call scribble_alloc() from resize_chunk() does not have the expected behavior. kvmalloc_array() inside scribble_alloc() which receives the GFP_NOIO flag will eventually call kmalloc_node() to allocate physically continuous pages. Now we have memalloc scope APIs in mddev_suspend()/mddev_resume() to prevent memory reclaim I/Os during raid array suspend context, calling to kvmalloc_array() with GFP_KERNEL flag may avoid deadlock of recursive I/O as expected. This patch removes the useless gfp flags from parameters list of scribble_alloc(), and call kvmalloc_array() with GFP_KERNEL flag. The incorrect GFP_NOIO flag does not exist anymore. Fixes: b330e6a49dc3 ("md: convert to kvmalloc") Suggested-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
d2c9ad41 |
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20-Dec-2019 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: remove worker_cnt_per_group argument from alloc_thread_groups We can use "cnt" directly to update conf->worker_cnt_per_group if alloc_thread_groups returns 0. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
a7ede3d1 |
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27-Nov-2019 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: need to set STRIPE_HANDLE for batch head With commit 6ce220dd2f8ea71d6afc29b9a7524c12e39f374a ("raid5: don't set STRIPE_HANDLE to stripe which is in batch list"), we don't want to set STRIPE_HANDLE flag for sh which is already in batch list. However, the stripe which is the head of batch list should set this flag, otherwise panic could happen inside init_stripe at BUG_ON(sh->batch_head), it is reproducible with raid5 on top of nvdimm devices per Xiao oberserved. Thanks for Xiao's effort to verify the change. Fixes: 6ce220dd2f8ea ("raid5: don't set STRIPE_HANDLE to stripe which is in batch list") Reported-by: Xiao Ni <xni@redhat.com> Tested-by: Xiao Ni <xni@redhat.com> Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
f1934892 |
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20-Sep-2019 |
Eugene Syromiatnikov <esyr@redhat.com> |
drivers/md/raid5.c: use the new spelling of RWH_WRITE_LIFE_NOT_SET As it is consistent with prefixes of other write life time hints. Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
775d7831 |
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16-Sep-2019 |
David Jeffery <djeffery@redhat.com> |
md: improve handling of bio with REQ_PREFLUSH in md_flush_request() If pers->make_request fails in md_flush_request(), the bio is lost. To fix this, pass back a bool to indicate if the original make_request call should continue to handle the I/O and instead of assuming the flush logic will push it to completion. Convert md_flush_request to return a bool and no longer calls the raid driver's make_request function. If the return is true, then the md flush logic has or will complete the bio and the md make_request call is done. If false, then the md make_request function needs to keep processing like it is a normal bio. Let the original call to md_handle_request handle any need to retry sending the bio to the raid driver's make_request function should it be needed. Also mark md_flush_request and the make_request function pointer as __must_check to issue warnings should these critical return values be ignored. Fixes: 2bc13b83e629 ("md: batch flush requests.") Cc: stable@vger.kernel.org # # v4.19+ Cc: NeilBrown <neilb@suse.com> Signed-off-by: David Jeffery <djeffery@redhat.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
feb9bf98 |
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11-Sep-2019 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: remove STRIPE_OPS_REQ_PENDING This stripe state is not used anymore after commit 51acbcec6c42b24 ("md: remove CONFIG_MULTICORE_RAID456"), so remove the obsoleted state. gjiang@nb01257:~/md$ grep STRIPE_OPS_REQ_PENDING drivers/md/ -r drivers/md/raid5.c: (1 << STRIPE_OPS_REQ_PENDING) | drivers/md/raid5.h: STRIPE_OPS_REQ_PENDING, Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
6ce220dd |
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11-Sep-2019 |
Guoqing Jiang <guoqing.jiang@cloud.ionos.com> |
raid5: don't set STRIPE_HANDLE to stripe which is in batch list If stripe in batch list is set with STRIPE_HANDLE flag, then the stripe could be set with STRIPE_ACTIVE by the handle_stripe function. And if error happens to the batch_head at the same time, break_stripe_batch_list is called, then below warning could happen (the same report in [1]), it means a member of batch list was set with STRIPE_ACTIVE. [7028915.431770] stripe state: 2001 [7028915.431815] ------------[ cut here ]------------ [7028915.431828] WARNING: CPU: 18 PID: 29089 at drivers/md/raid5.c:4614 break_stripe_batch_list+0x203/0x240 [raid456] [...] [7028915.431879] CPU: 18 PID: 29089 Comm: kworker/u82:5 Tainted: G O 4.14.86-1-storage #4.14.86-1.2~deb9 [7028915.431881] Hardware name: Supermicro SSG-2028R-ACR24L/X10DRH-iT, BIOS 3.1 06/18/2018 [7028915.431888] Workqueue: raid5wq raid5_do_work [raid456] [7028915.431890] task: ffff9ab0ef36d7c0 task.stack: ffffb72926f84000 [7028915.431896] RIP: 0010:break_stripe_batch_list+0x203/0x240 [raid456] [7028915.431898] RSP: 0018:ffffb72926f87ba8 EFLAGS: 00010286 [7028915.431900] RAX: 0000000000000012 RBX: ffff9aaa84a98000 RCX: 0000000000000000 [7028915.431901] RDX: 0000000000000000 RSI: ffff9ab2bfa15458 RDI: ffff9ab2bfa15458 [7028915.431902] RBP: ffff9aaa8fb4e900 R08: 0000000000000001 R09: 0000000000002eb4 [7028915.431903] R10: 00000000ffffffff R11: 0000000000000000 R12: ffff9ab1736f1b00 [7028915.431904] R13: 0000000000000000 R14: ffff9aaa8fb4e900 R15: 0000000000000001 [7028915.431906] FS: 0000000000000000(0000) GS:ffff9ab2bfa00000(0000) knlGS:0000000000000000 [7028915.431907] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [7028915.431908] CR2: 00007ff953b9f5d8 CR3: 0000000bf4009002 CR4: 00000000003606e0 [7028915.431909] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [7028915.431910] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [7028915.431910] Call Trace: [7028915.431923] handle_stripe+0x8e7/0x2020 [raid456] [7028915.431930] ? __wake_up_common_lock+0x89/0xc0 [7028915.431935] handle_active_stripes.isra.58+0x35f/0x560 [raid456] [7028915.431939] raid5_do_work+0xc6/0x1f0 [raid456] Also commit 59fc630b8b5f9f ("RAID5: batch adjacent full stripe write") said "If a stripe is added to batch list, then only the first stripe of the list should be put to handle_list and run handle_stripe." So don't set STRIPE_HANDLE to stripe which is already in batch list, otherwise the stripe could be put to handle_list and run handle_stripe, then the above warning could be triggered. [1]. https://www.spinics.net/lists/raid/msg62552.html Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
b76b4715 |
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06-Sep-2019 |
Nigel Croxon <ncroxon@redhat.com> |
raid5: don't increment read_errors on EILSEQ return While MD continues to count read errors returned by the lower layer. If those errors are -EILSEQ, instead of -EIO, it should NOT increase the read_errors count. When RAID6 is set up on dm-integrity target that detects massive corruption, the leg will be ejected from the array. Even if the issue is correctable with a sector re-write and the array has necessary redundancy to correct it. The leg is ejected because it runs up the rdev->read_errors beyond conf->max_nr_stripes. The return status in dm-drypt when there is a data integrity error is -EILSEQ (BLK_STS_PROTECTION). Signed-off-by: Nigel Croxon <ncroxon@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
b0f01ecf |
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03-Sep-2019 |
Guoqing Jiang <jgq516@gmail.com> |
md/raid5: use bio_end_sector to calculate last_sector Use the common way to get last_sector. Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
0009fad0 |
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21-Aug-2019 |
Nigel Croxon <ncroxon@redhat.com> |
raid5 improve too many read errors msg by adding limits Often limits can be changed by admin. When discussing such things it helps if you can provide "self-sustained" facts. Also sometimes the admin thinks he changed a limit, but it did not take effect for some reason or he changed the wrong thing. V3: Only pr_warn when Faulty is 0. V2: Add read_errors value to pr_warn. Signed-off-by: Nigel Croxon <ncroxon@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
143f6e73 |
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07-Jul-2019 |
Xiao Ni <xni@redhat.com> |
md/raid6: Set R5_ReadError when there is read failure on parity disk 7471fb77ce4d ("md/raid6: Fix anomily when recovering a single device in RAID6.") avoids rereading P when it can be computed from other members. However, this misses the chance to re-write the right data to P. This patch sets R5_ReadError if the re-read fails. Also, when re-read is skipped, we also missed the chance to reset rdev->read_errors to 0. It can fail the disk when there are many read errors on P member disk (other disks don't have read error) V2: upper layer read request don't read parity/Q data. So there is no need to consider such situation. This is Reported-by: kbuild test robot <lkp@intel.com> Fixes: 7471fb77ce4d ("md/raid6: Fix anomily when recovering a single device in RAID6.") Cc: <stable@vger.kernel.org> #4.4+ Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
14ccb66b |
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05-Jun-2019 |
Christoph Hellwig <hch@lst.de> |
block: remove the bi_phys_segments field in struct bio We only need the number of segments in the blk-mq submission path. Remove the field from struct bio, and return it from a variant of blk_queue_split instead of that it can passed as an argument to those functions that need the value. This also means we stop recounting segments except for cloning and partial segments. To keep the number of arguments in this how path down remove pointless struct request_queue arguments from any of the functions that had it and grew a nr_segs argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
d9771f5e |
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14-Jun-2019 |
Xiao Ni <xni@redhat.com> |
raid5-cache: Need to do start() part job after adding journal device commit d5d885fd514f ("md: introduce new personality funciton start()") splits the init job to two parts. The first part run() does the jobs that do not require the md threads. The second part start() does the jobs that require the md threads. Now it just does run() in adding new journal device. It needs to do the second part start() too. Fixes: d5d885fd514f ("md: introduce new personality funciton start()") Cc: stable@vger.kernel.org #v4.9+ Reported-by: Michal Soltys <soltys@ziu.info> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
af1a8899 |
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20-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version you should have received a copy of the gnu general public license for example usr src linux copying if not write to the free software foundation inc 675 mass ave cambridge ma 02139 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 20 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170858.552543146@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
b2176a1d |
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16-Apr-2019 |
Nigel Croxon <ncroxon@redhat.com> |
md/raid: raid5 preserve the writeback action after the parity check The problem is that any 'uptodate' vs 'disks' check is not precise in this path. Put a "WARN_ON(!test_bit(R5_UPTODATE, &dev->flags)" on the device that might try to kick off writes and then skip the action. Better to prevent the raid driver from taking unexpected action *and* keep the system alive vs killing the machine with BUG_ON. Note: fixed warning reported by kbuild test robot <lkp@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Nigel Croxon <ncroxon@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
a25d8c32 |
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16-Apr-2019 |
Song Liu <songliubraving@fb.com> |
Revert "Don't jump to compute_result state from check_result state" This reverts commit 4f4fd7c5798bbdd5a03a60f6269cf1177fbd11ef. Cc: Dan Williams <dan.j.williams@intel.com> Cc: Nigel Croxon <ncroxon@redhat.com> Cc: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
efcd487c |
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04-Apr-2019 |
Christoph Hellwig <hch@lst.de> |
md: add __acquires/__releases annotations to handle_active_stripes This tells sparse that we release and reacquire the device_lock and avoids a warning. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
368ecade |
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04-Apr-2019 |
Christoph Hellwig <hch@lst.de> |
md: add __acquires/__releases annotations to (un)lock_two_stripes This tells sparse that we acquire/release the two stripe locks and avoids a warning. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
4f4fd7c5 |
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29-Mar-2019 |
Nigel Croxon <ncroxon@redhat.com> |
Don't jump to compute_result state from check_result state Changing state from check_state_check_result to check_state_compute_result not only is unsafe but also doesn't appear to serve a valid purpose. A raid6 check should only be pushing out extra writes if doing repair and a mis-match occurs. The stripe dev management will already try and do repair writes for failing sectors. This patch makes the raid6 check_state_check_result handling work more like raid5's. If somehow too many failures for a check, just quit the check operation for the stripe. When any checks pass, don't try and use check_state_compute_result for a purpose it isn't needed for and is unsafe for. Just mark the stripe as in sync for passing its parity checks and let the stripe dev read/write code and the bad blocks list do their job handling I/O errors. Repro steps from Xiao: These are the steps to reproduce this problem: 1. redefined OPT_MEDIUM_ERR_ADDR to 12000 in scsi_debug.c 2. insmod scsi_debug.ko dev_size_mb=11000 max_luns=1 num_tgts=1 3. mdadm --create /dev/md127 --level=6 --raid-devices=5 /dev/sde1 /dev/sde2 /dev/sde3 /dev/sde5 /dev/sde6 sde is the disk created by scsi_debug 4. echo "2" >/sys/module/scsi_debug/parameters/opts 5. raid-check It panic: [ 4854.730899] md: data-check of RAID array md127 [ 4854.857455] sd 5:0:0:0: [sdr] tag#80 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.859246] sd 5:0:0:0: [sdr] tag#80 Sense Key : Medium Error [current] [ 4854.860694] sd 5:0:0:0: [sdr] tag#80 Add. Sense: Unrecovered read error [ 4854.862207] sd 5:0:0:0: [sdr] tag#80 CDB: Read(10) 28 00 00 00 2d 88 00 04 00 00 [ 4854.864196] print_req_error: critical medium error, dev sdr, sector 11656 flags 0 [ 4854.867409] sd 5:0:0:0: [sdr] tag#100 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.869469] sd 5:0:0:0: [sdr] tag#100 Sense Key : Medium Error [current] [ 4854.871206] sd 5:0:0:0: [sdr] tag#100 Add. Sense: Unrecovered read error [ 4854.872858] sd 5:0:0:0: [sdr] tag#100 CDB: Read(10) 28 00 00 00 2e e0 00 00 08 00 [ 4854.874587] print_req_error: critical medium error, dev sdr, sector 12000 flags 4000 [ 4854.876456] sd 5:0:0:0: [sdr] tag#101 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.878552] sd 5:0:0:0: [sdr] tag#101 Sense Key : Medium Error [current] [ 4854.880278] sd 5:0:0:0: [sdr] tag#101 Add. Sense: Unrecovered read error [ 4854.881846] sd 5:0:0:0: [sdr] tag#101 CDB: Read(10) 28 00 00 00 2e e8 00 00 08 00 [ 4854.883691] print_req_error: critical medium error, dev sdr, sector 12008 flags 4000 [ 4854.893927] sd 5:0:0:0: [sdr] tag#166 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 4854.896002] sd 5:0:0:0: [sdr] tag#166 Sense Key : Medium Error [current] [ 4854.897561] sd 5:0:0:0: [sdr] tag#166 Add. Sense: Unrecovered read error [ 4854.899110] sd 5:0:0:0: [sdr] tag#166 CDB: Read(10) 28 00 00 00 2e e0 00 00 10 00 [ 4854.900989] print_req_error: critical medium error, dev sdr, sector 12000 flags 0 [ 4854.902757] md/raid:md127: read error NOT corrected!! (sector 9952 on sdr1). [ 4854.904375] md/raid:md127: read error NOT corrected!! (sector 9960 on sdr1). [ 4854.906201] ------------[ cut here ]------------ [ 4854.907341] kernel BUG at drivers/md/raid5.c:4190! raid5.c:4190 above is this BUG_ON: handle_parity_checks6() ... BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */ Cc: <stable@vger.kernel.org> # v3.16+ OriginalAuthor: David Jeffery <djeffery@redhat.com> Cc: Xiao Ni <xni@redhat.com> Tested-by: David Jeffery <djeffery@redhat.com> Signed-off-by: David Jeffy <djeffery@redhat.com> Signed-off-by: Nigel Croxon <ncroxon@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
e406f12d |
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04-Mar-2019 |
Aditya Pakki <pakki001@umn.edu> |
md: Fix failed allocation of md_register_thread mddev->sync_thread can be set to NULL on kzalloc failure downstream. The patch checks for such a scenario and frees allocated resources. Committer node: Added similar fix to raid5.c, as suggested by Guoqing. Cc: stable@vger.kernel.org # v3.16+ Acked-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Aditya Pakki <pakki001@umn.edu> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
a596d086 |
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18-Feb-2019 |
Mariusz Dabrowski <mariusz.dabrowski@intel.com> |
raid5: set write hint for PPL When the Partial Parity Log is enabled, circular buffer is used to store PPL data. Each write to RAID device causes overwrite of data in this buffer so some write_hint can be set to those request to help drives handle garbage collection. This patch adds new sysfs attribute which can be used to specify which write_hint should be assigned to PPL. Acked-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Mariusz Dabrowski <mariusz.dabrowski@intel.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
b330e6a4 |
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12-Mar-2019 |
Kent Overstreet <kent.overstreet@gmail.com> |
md: convert to kvmalloc The code really just wants a big flat buffer, so just do that. Link: http://lkml.kernel.org/r/20181217131929.11727-3-kent.overstreet@gmail.com Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Cc: Shaohua Li <shli@kernel.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Eric Paris <eparis@parisplace.org> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
483cbbed |
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27-Mar-2018 |
Alexei Naberezhnov <anaberezhnov@fb.com> |
md/raid5: fix 'out of memory' during raid cache recovery This fixes the case when md array assembly fails because of raid cache recovery unable to allocate a stripe, despite attempts to replay stripes and increase cache size. This happens because stripes released by r5c_recovery_replay_stripes and raid5_set_cache_size don't become available for allocation immediately. Released stripes first are placed on conf->released_stripes list and require md thread to merge them on conf->inactive_list before they can be allocated. Patch allows final allocation attempt during cache recovery to wait for new stripes to become availabe for allocation. Cc: linux-raid@vger.kernel.org Cc: Shaohua Li <shli@kernel.org> Cc: linux-stable <stable@vger.kernel.org> # 4.10+ Fixes: b4c625c67362 ("md/r5cache: r5cache recovery: part 1") Signed-off-by: Alexei Naberezhnov <anaberezhnov@fb.com> Signed-off-by: Song Liu <songliubraving@fb.com>
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#
fb73b357 |
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04-Sep-2018 |
Mariusz Tkaczyk <mariusz.tkaczyk@intel.com> |
raid5: block failing device if raid will be failed Currently there is an inconsistency for failing the member drives for arrays with different RAID levels. For RAID456 - there is a possibility to fail all of the devices. However - for other RAID levels - kernel blocks removing the member drive, if the operation results in array's FAIL state (EBUSY is returned). For example - removing last drive from RAID1 is not possible. This kind of blocker was never implemented for raid456 and we cannot see the reason why. We had tested following patch and did not observe any regression, so do you have any comments/reasons for current approach, or we can send the proper patch for this? Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
e254de6b |
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29-Aug-2018 |
Shaohua Li <shli@fb.com> |
md/raid5-cache: disable reshape completely We don't support reshape yet if an array supports log device. Previously we determine the fact by checking ->log. However, ->log could be NULL after a log device is removed, but the array is still marked to support log device. Don't allow reshape in this case too. User can disable log device support by setting 'consistency_policy' to 'resync' then do reshape. Reported-by: Xiao Ni <xni@redhat.com> Tested-by: Xiao Ni <xni@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
d63e2fc8 |
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01-Aug-2018 |
BingJing Chang <bingjingc@synology.com> |
md/raid5: fix data corruption of replacements after originals dropped During raid5 replacement, the stripes can be marked with R5_NeedReplace flag. Data can be read from being-replaced devices and written to replacing spares without reading all other devices. (It's 'replace' mode. s.replacing = 1) If a being-replaced device is dropped, the replacement progress will be interrupted and resumed with pure recovery mode. However, existing stripes before being interrupted cannot read from the dropped device anymore. It prints lots of WARN_ON messages. And it results in data corruption because existing stripes write problematic data into its replacement device and update the progress. \# Erase disks (1MB + 2GB) dd if=/dev/zero of=/dev/sda bs=1MB count=2049 dd if=/dev/zero of=/dev/sdb bs=1MB count=2049 dd if=/dev/zero of=/dev/sdc bs=1MB count=2049 dd if=/dev/zero of=/dev/sdd bs=1MB count=2049 mdadm -C /dev/md0 -amd -R -l5 -n3 -x0 /dev/sd[abc] -z 2097152 \# Ensure array stores non-zero data dd if=/root/data_4GB.iso of=/dev/md0 bs=1MB \# Start replacement mdadm /dev/md0 -a /dev/sdd mdadm /dev/md0 --replace /dev/sda Then, Hot-plug out /dev/sda during recovery, and wait for recovery done. echo check > /sys/block/md0/md/sync_action cat /sys/block/md0/md/mismatch_cnt # it will be greater than 0. Soon after you hot-plug out /dev/sda, you will see many WARN_ON messages. The replacement recovery will be interrupted shortly. After the recovery finishes, it will result in data corruption. Actually, it's just an unhandled case of replacement. In commit <f94c0b6658c7> (md/raid5: fix interaction of 'replace' and 'recovery'.), if a NeedReplace device is not UPTODATE then that is an error, the commit just simply print WARN_ON but also mark these corrupted stripes with R5_WantReplace. (it means it's ready for writes.) To fix this case, we can leverage 'sync and replace' mode mentioned in commit <9a3e1101b827> (md/raid5: detect and handle replacements during recovery.). We can add logics to detect and use 'sync and replace' mode for these stripes. Reported-by: Alex Chen <alexchen@synology.com> Reviewed-by: Alex Wu <alexwu@synology.com> Reviewed-by: Chung-Chiang Cheng <cccheng@synology.com> Signed-off-by: BingJing Chang <bingjingc@synology.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
e64e4018 |
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01-Aug-2018 |
Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
md: Avoid namespace collision with bitmap API bitmap API (include/linux/bitmap.h) has 'bitmap' prefix for its methods. On the other hand MD bitmap API is special case. Adding 'md' prefix to it to avoid name space collision. No functional changes intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Shaohua Li <shli@kernel.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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#
08edaaa6 |
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03-Jul-2018 |
Anna-Maria Gleixner <anna-maria@linutronix.de> |
drivers/md/raid5: Do not disable irq on release_inactive_stripe_list() call There is no need to invoke release_inactive_stripe_list() with interrupts disabled. All call sites, except raid5_release_stripe(), unlock ->device_lock and enable interrupts before invoking the function. Make it consistent. Cc: Shaohua Li <shli@kernel.org> Cc: linux-raid@vger.kernel.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Shaohua Li <shli@fb.com>
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#
685dbcaa |
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03-Jul-2018 |
Anna-Maria Gleixner <anna-maria@linutronix.de> |
drivers/md/raid5: Use irqsave variant of atomic_dec_and_lock() The irqsave variant of atomic_dec_and_lock handles irqsave/restore when taking/releasing the spin lock. With this variant the call of local_irq_save is no longer required. Cc: Shaohua Li <shli@kernel.org> Cc: linux-raid@vger.kernel.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Shaohua Li <shli@fb.com>
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#
6396bb22 |
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12-Jun-2018 |
Kees Cook <keescook@chromium.org> |
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
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#
afeee514 |
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20-May-2018 |
Kent Overstreet <kent.overstreet@gmail.com> |
md: convert to bioset_init()/mempool_init() Convert md to embedded bio sets. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
448ec638 |
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16-May-2018 |
Amy Chiang <amychiang@qnap.com> |
md/raid5: Assigning NULL to sh->batch_head before testing bit R5_Overlap of a stripe In add_stripe_bio(), if the stripe_head is in batch list, the incoming bio is regarded as overlapping, and the bit R5_Overlap on this stripe_head is set. break_stripe_batch_list() checks bit R5_Overlap on each stripe_head first then assigns NULL to sh->batch_head. If break_stripe_batch_list() checks bit R5_Overlap on stripe_head A after add_stripe_bio() finds stripe_head A is in batch list and before add_stripe_bio() sets bit R5_Overlapt of stripe_head A, break_stripe_batch_list() would not know there's a process in wait_for_overlap and needs to call wake_up(). There's a huge chance a process never returns from schedule() if add_stripe_bio() is called from raid5_make_request(). In break_stripe_batch_list(), assigning NULL to sh->batch_head should be done before it checks bit R5_Overlap of a stripe_head. Signed-off-by: Amy Chiang <amychiang@qnap.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
2cd259a7 |
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19-Apr-2018 |
Mariusz Dabrowski <mariusz.dabrowski@intel.com> |
raid5: copy write hint from origin bio to stripe Store write hint from original bio in stripe head so it can be assigned to bio sent to each RAID device. Signed-off-by: Mariusz Dabrowski <mariusz.dabrowski@intel.com> Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Reviewed-by: Pawel Baldysiak <pawel.baldysiak@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
8b904b5b |
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07-Mar-2018 |
Bart Van Assche <bvanassche@acm.org> |
block: Use blk_queue_flag_*() in drivers instead of queue_flag_*() This patch has been generated as follows: for verb in set_unlocked clear_unlocked set clear; do replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \ $(git grep -lw queue_flag_${verb} drivers block/bsg*) done Except for protecting all queue flag changes with the queue lock this patch does not change any functionality. Cc: Mike Snitzer <snitzer@redhat.com> Cc: Shaohua Li <shli@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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#
8876391e |
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21-Feb-2018 |
BingJing Chang <bingjingc@synology.com> |
md: fix a potential deadlock of raid5/raid10 reshape There is a potential deadlock if mount/umount happens when raid5_finish_reshape() tries to grow the size of emulated disk. How the deadlock happens? 1) The raid5 resync thread finished reshape (expanding array). 2) The mount or umount thread holds VFS sb->s_umount lock and tries to write through critical data into raid5 emulated block device. So it waits for raid5 kernel thread handling stripes in order to finish it I/Os. 3) In the routine of raid5 kernel thread, md_check_recovery() will be called first in order to reap the raid5 resync thread. That is, raid5_finish_reshape() will be called. In this function, it will try to update conf and call VFS revalidate_disk() to grow the raid5 emulated block device. It will try to acquire VFS sb->s_umount lock. The raid5 kernel thread cannot continue, so no one can handle mount/ umount I/Os (stripes). Once the write-through I/Os cannot be finished, mount/umount will not release sb->s_umount lock. The deadlock happens. The raid5 kernel thread is an emulated block device. It is responible to handle I/Os (stripes) from upper layers. The emulated block device should not request any I/Os on itself. That is, it should not call VFS layer functions. (If it did, it will try to acquire VFS locks to guarantee the I/Os sequence.) So we have the resync thread to send resync I/O requests and to wait for the results. For solving this potential deadlock, we can put the size growth of the emulated block device as the final step of reshape thread. 2017/12/29: Thanks to Guoqing Jiang <gqjiang@suse.com>, we confirmed that there is the same deadlock issue in raid10. It's reproducible and can be fixed by this patch. For raid10.c, we can remove the similar code to prevent deadlock as well since they has been called before. Reported-by: Alex Wu <alexwu@synology.com> Reviewed-by: Alex Wu <alexwu@synology.com> Reviewed-by: Chung-Chiang Cheng <cccheng@synology.com> Signed-off-by: BingJing Chang <bingjingc@synology.com> Signed-off-by: Shaohua Li <sh.li@alibaba-inc.com>
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#
53b8d89d |
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20-Feb-2018 |
Arnd Bergmann <arnd@arndb.de> |
md: raid5: avoid string overflow warning gcc warns about a possible overflow of the kmem_cache string, when adding four characters to a string of the same length: drivers/md/raid5.c: In function 'setup_conf': drivers/md/raid5.c:2207:34: error: '-alt' directive writing 4 bytes into a region of size between 1 and 32 [-Werror=format-overflow=] sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]); ^~~~ drivers/md/raid5.c:2207:2: note: 'sprintf' output between 5 and 36 bytes into a destination of size 32 sprintf(conf->cache_name[1], "%s-alt", conf->cache_name[0]); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ If I'm counting correctly, we need 11 characters for the fixed part of the string and 18 characters for a 64-bit pointer (when no gendisk is used), so that leaves three characters for conf->level, which should always be sufficient. This makes the code use snprintf() with the correct length, to make the code more robust against changes, and to get the compiler to shut up. In commit f4be6b43f1ac ("md/raid5: ensure we create a unique name for kmem_cache when mddev has no gendisk") from 2010, Neil said that the pointer could be removed "shortly" once devices without gendisk are disallowed. I have no idea if that happened, but if it did, that should probably be changed as well. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Shaohua Li <sh.li@alibaba-inc.com>
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#
565e0450 |
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23-Dec-2017 |
Aliaksei Karaliou <akaraliou.dev@gmail.com> |
md/raid5: simplify uninitialization of shrinker Don't use shrinker.nr_deferred to check whether shrinker was initialized or not. Now this check was integrated into unregister_shrinker(), so it is safe to call it against unregistered shrinker. Signed-off-by: Aliaksei Karaliou <akaraliou.dev@gmail.com> Signed-off-by: Shaohua Li <sh.li@alibaba-inc.com>
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1532d9e8 |
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27-Dec-2017 |
Tomasz Majchrzak <tomasz.majchrzak@intel.com> |
raid5-ppl: PPL support for disks with write-back cache enabled In order to provide data consistency with PPL for disks with write-back cache enabled all data has to be flushed to disks before next PPL entry. The disks to be flushed are marked in the bitmap. It's modified under a mutex and it's only read after PPL io unit is submitted. A limitation of 64 disks in the array has been introduced to keep data structures and implementation simple. RAID5 arrays with so many disks are not likely due to high risk of multiple disks failure. Such restriction should not be a real life limitation. With write-back cache disabled next PPL entry is submitted when data write for current one completes. Data flush defers next log submission so trigger it when there are no stripes for handling found. As PPL assures all data is flushed to disk at request completion, just acknowledge flush request when PPL is enabled. Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com> Signed-off-by: Shaohua Li <sh.li@alibaba-inc.com>
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#
d5d885fd |
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19-Nov-2017 |
Song Liu <songliubraving@fb.com> |
md: introduce new personality funciton start() In do_md_run(), md threads should not wake up until the array is fully initialized in md_run(). However, in raid5_run(), raid5-cache may wake up mddev->thread to flush stripes that need to be written back. This design doesn't break badly right now. But it could lead to bad bug in the future. This patch tries to resolve this problem by splitting start up work into two personality functions, run() and start(). Tasks that do not require the md threads should go into run(), while task that require the md threads go into start(). r5l_load_log() is moved to raid5_start(), so it is not called until the md threads are started in do_md_run(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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aff69d89 |
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16-Nov-2017 |
bingjingc <bingjingc@synology.com> |
md/raid5: correct degraded calculation in raid5_error When disk failure occurs on new disks for reshape, mddev->degraded is not calculated correctly. Faulty bit of the failure device is not set before raid5_calc_degraded(conf). mdadm --create /dev/md0 --level=5 --raid-devices=3 /dev/loop[012] mdadm /dev/md0 -a /dev/loop3 mdadm /dev/md0 --grow -n4 mdadm /dev/md0 -f /dev/loop3 # simulating disk failure cat /sys/block/md0/md/degraded # it outputs 0, but it should be 1. However, mdadm -D /dev/md0 will show that it is degraded. It's a bug. It can be fixed by moving the resources raid5_calc_degraded() depends on before it. Reported-by: Roy Chung <roychung@synology.com> Reviewed-by: Alex Wu <alexwu@synology.com> Signed-off-by: BingJing Chang <bingjingc@synology.com> Signed-off-by: Shaohua Li <shli@fb.com>
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db0505d3 |
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16-Oct-2017 |
NeilBrown <neilb@suse.com> |
md: be cautious about using ->curr_resync_completed for ->recovery_offset The ->recovery_offset shows how much of a non-InSync device is actually in sync - how much has been recoveryed. When performing a recovery, ->curr_resync and ->curr_resync_completed follow the device address being recovered and so can be used to update ->recovery_offset. When performing a reshape, ->curr_resync* might follow the device addresses (raid5) or might follow array addresses (raid10), so cannot in general be used to set ->recovery_offset. When reshaping backwards, ->curre_resync* measures from the *end* of the array-or-device, so is particularly unhelpful. So change the common code in md.c to only use ->curr_resync_complete for the simple recovery case, and add code to raid5.c to update ->recovery_offset during a forwards reshape. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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ae89fd3d |
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18-Oct-2017 |
Mikulas Patocka <mpatocka@redhat.com> |
md: use TASK_IDLE instead of blocking signals Hi - I submit this patch for the next merge window: Some times ago, I made a patch f9c79bc05a2a that blocks signals around the schedule() calls in MD. The MD subsystem needs to do an uninterruptible sleep that is not accounted in load average - so we block signals and use interruptible sleep. The kernel has a special TASK_IDLE state for this purpose, so we can use it instead of blocking signals. This patch doesn't fix any bug, it just makes the code simpler. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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b03e0ccb |
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18-Oct-2017 |
NeilBrown <neilb@suse.com> |
md: remove special meaning of ->quiesce(.., 2) The '2' argument means "wake up anything that is waiting". This is an inelegant part of the design and was added to help support management of suspend_lo/suspend_hi setting. Now that suspend_lo/hi is managed in mddev_suspend/resume, that need is gone. These is still a couple of places where we call 'quiesce' with an argument of '2', but they can safely be changed to call ->quiesce(.., 1); ->quiesce(.., 0) which achieve the same result at the small cost of pausing IO briefly. This removes a small "optimization" from suspend_{hi,lo}_store, but it isn't clear that optimization served a useful purpose. The code now is a lot clearer. Suggested-by: Shaohua Li <shli@kernel.org> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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b3143b9a |
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16-Oct-2017 |
NeilBrown <neilb@suse.com> |
md: move suspend_hi/lo handling into core md code responding to ->suspend_lo and ->suspend_hi is similar to responding to ->suspended. It is best to wait in the common core code without incrementing ->active_io. This allows mddev_suspend()/mddev_resume() to work while requests are waiting for suspend_lo/hi to change. This is will be important after a subsequent patch which uses mddev_suspend() to synchronize updating for suspend_lo/hi. So move the code for testing suspend_lo/hi out of raid1.c and raid5.c, and place it in md.c Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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230b55fa |
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16-Oct-2017 |
NeilBrown <neilb@suse.com> |
md: forbid a RAID5 from having both a bitmap and a journal. Having both a bitmap and a journal is pointless. Attempting to do so can corrupt the bitmap if the journal replay happens before the bitmap is initialized. Rather than try to avoid this corruption, simply refuse to allow arrays with both a bitmap and a journal. So: - if raid5_run sees both are present, fail. - if adding a bitmap finds a journal is present, fail - if adding a journal finds a bitmap is present, fail. Cc: stable@vger.kernel.org (4.10+) Signed-off-by: NeilBrown <neilb@suse.com> Tested-by: Joshua Kinard <kumba@gentoo.org> Acked-by: Joshua Kinard <kumba@gentoo.org> Signed-off-by: Shaohua Li <shli@fb.com>
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6aa7de05 |
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23-Oct-2017 |
Mark Rutland <mark.rutland@arm.com> |
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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235b6003 |
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16-Oct-2017 |
NeilBrown <neilb@suse.com> |
raid5: Set R5_Expanded on parity devices as well as data. When reshaping a fully degraded raid5/raid6 to a larger nubmer of devices, the new device(s) are not in-sync and so that can make the newly grown stripe appear to be "failed". To avoid this, we set the R5_Expanded flag to say "Even though this device is not fully in-sync, this block is safe so don't treat the device as failed for this stripe". This flag is set for data devices, not not for parity devices. Consequently, if you have a RAID6 with two devices that are partly recovered and a spare, and start a reshape to include the spare, then when the reshape gets past the point where the recovery was up to, it will think the stripes are failed and will get into an infinite loop, failing to make progress. So when contructing parity on an EXPAND_READY stripe, set R5_Expanded. Reported-by: Curt <lightspd@gmail.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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935fe098 |
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10-Oct-2017 |
Mike Snitzer <snitzer@redhat.com> |
md: rename some drivers/md/ files to have an "md-" prefix Motivated by the desire to illiminate the imprecise nature of DM-specific patches being unnecessarily sent to both the MD maintainer and mailing-list. Which is born out of the fact that DM files also reside in drivers/md/ Now all MD-specific files in drivers/md/ start with either "raid" or "md-" and the MAINTAINERS file has been updated accordingly. Shaohua: don't change module name Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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7d5d7b50 |
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21-Sep-2017 |
Shaohua Li <shli@fb.com> |
md/raid5: cap worker count static checker reports a potential integer overflow. Cap the worker count to avoid the overflow. Reported:-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com>
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184a09eb |
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05-Sep-2017 |
Dennis Yang <dennisyang@qnap.com> |
md/raid5: preserve STRIPE_ON_UNPLUG_LIST in break_stripe_batch_list In release_stripe_plug(), if a stripe_head has its STRIPE_ON_UNPLUG_LIST set, it indicates that this stripe_head is already in the raid5_plug_cb list and release_stripe() would be called instead to drop a reference count. Otherwise, the STRIPE_ON_UNPLUG_LIST bit would be set for this stripe_head and it will get queued into the raid5_plug_cb list. Since break_stripe_batch_list() did not preserve STRIPE_ON_UNPLUG_LIST, A stripe could be re-added to plug list while it is still on that list in the following situation. If stripe_head A is added to another stripe_head B's batch list, in this case A will have its batch_head != NULL and be added into the plug list. After that, stripe_head B gets handled and called break_stripe_batch_list() to reset all the batched stripe_head(including A which is still on the plug list)'s state and reset their batch_head to NULL. Before the plug list gets processed, if there is another write request comes in and get stripe_head A, A will have its batch_head == NULL (cleared by calling break_stripe_batch_list() on B) and be added to plug list once again. Signed-off-by: Dennis Yang <dennisyang@qnap.com> Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: Shaohua Li <shli@fb.com>
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3664847d |
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25-Aug-2017 |
Shaohua Li <shli@fb.com> |
md/raid5: fix a race condition in stripe batch We have a race condition in below scenario, say have 3 continuous stripes, sh1, sh2 and sh3, sh1 is the stripe_head of sh2 and sh3: CPU1 CPU2 CPU3 handle_stripe(sh3) stripe_add_to_batch_list(sh3) -> lock(sh2, sh3) -> lock batch_lock(sh1) -> add sh3 to batch_list of sh1 -> unlock batch_lock(sh1) clear_batch_ready(sh1) -> lock(sh1) and batch_lock(sh1) -> clear STRIPE_BATCH_READY for all stripes in batch_list -> unlock(sh1) and batch_lock(sh1) ->clear_batch_ready(sh3) -->test_and_clear_bit(STRIPE_BATCH_READY, sh3) --->return 0 as sh->batch == NULL -> sh3->batch_head = sh1 -> unlock (sh2, sh3) In CPU1, handle_stripe will continue handle sh3 even it's in batch stripe list of sh1. By moving sh3->batch_head assignment in to batch_lock, we make it impossible to clear STRIPE_BATCH_READY before batch_head is set. Thanks Stephane for helping debug this tricky issue. Reported-and-tested-by: Stephane Thiell <sthiell@stanford.edu> Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: Shaohua Li <shli@fb.com>
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ddc08823 |
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16-Aug-2017 |
Pawel Baldysiak <pawel.baldysiak@intel.com> |
md: Runtime support for multiple ppls Increase PPL area to 1MB and use it as circular buffer to store PPL. The entry with highest generation number is the latest one. If PPL to be written is larger then space left in a buffer, rewind the buffer to the start (don't wrap it). Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com> Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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27a4ff8f |
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10-Aug-2017 |
Guoqing Jiang <gqjiang@suse.com> |
raid5: remove raid5_build_block Now raid5_build_block is just called to set the sector of r5dev, raid5_compute_blocknr can be used directly for the purpose. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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9c72a18e4 |
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24-Aug-2017 |
Song Liu <songliubraving@fb.com> |
md/raid5: release/flush io in raid5_do_work() In raid5, there are scenarios where some ios are deferred to a later time, and some IO need a flush to complete. To make sure we make progress with these IOs, we need to call the following functions: flush_deferred_bios(conf); r5l_flush_stripe_to_raid(conf->log); Both of these functions are called in raid5d(), but missing in raid5_do_work(). As a result, these functions are not called when multi-threading (group_thread_cnt > 0) is enabled. This patch adds calls to these function to raid5_do_work(). Note for stable branches: r5l_flush_stripe_to_raid(conf->log) is need for 4.4+ flush_deferred_bios(conf) is only needed for 4.11+ Cc: stable@vger.kernel.org (4.4+) Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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74d46992 |
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23-Aug-2017 |
Christoph Hellwig <hch@lst.de> |
block: replace bi_bdev with a gendisk pointer and partitions index This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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10433d04 |
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23-Aug-2017 |
Christoph Hellwig <hch@lst.de> |
raid5: remove a call to get_start_sect The block layer always remaps partitions before calling into the ->make_request methods of drivers. Thus the call to get_start_sect in in_chunk_boundary will always return 0 and can be removed. Reviewed-by: Shaohua Li <shli@fb.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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7e96d559 |
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24-Jul-2017 |
Ofer Heifetz <oferh@marvell.com> |
md/raid5: add thread_group worker async_tx_issue_pending_all Since thread_group worker and raid5d kthread are not in sync, if worker writes stripe before raid5d then requests will be waiting for issue_pendig. Issue observed when building raid5 with ext4, in some build runs jbd2 would get hung and requests were waiting in the HW engine waiting to be issued. Fix this by adding a call to async_tx_issue_pending_all in the raid5_do_work. Signed-off-by: Ofer Heifetz <oferh@marvell.com> Cc: stable@vger.kernel.org Signed-off-by: Shaohua Li <shli@fb.com>
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6308d8e3 |
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21-Jul-2017 |
Guoqing Jiang <gqjiang@suse.com> |
md: simplify code with bio_io_error Since bio_io_error sets bi_status to BLK_STS_IOERR, and calls bio_endio, so we can use it directly. And as mentioned by Shaohua, there are also two places in raid5.c can use bio_io_error either. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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b5d27718 |
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05-Jul-2017 |
Xiao Ni <xni@redhat.com> |
Raid5 should update rdev->sectors after reshape The raid5 md device is created by the disks which we don't use the total size. For example, the size of the device is 5G and it just uses 3G of the devices to create one raid5 device. Then change the chunksize and wait reshape to finish. After reshape finishing stop the raid and assemble it again. It fails. mdadm -CR /dev/md0 -l5 -n3 /dev/loop[0-2] --size=3G --chunk=32 --assume-clean mdadm /dev/md0 --grow --chunk=64 wait reshape to finish mdadm -S /dev/md0 mdadm -As The error messages: [197519.814302] md: loop1 does not have a valid v1.2 superblock, not importing! [197519.821686] md: md_import_device returned -22 After reshape the data offset is changed. It selects backwards direction in this condition. In function super_1_load it compares the available space of the underlying device with sb->data_size. The new data offset gets bigger after reshape. So super_1_load returns -EINVAL. rdev->sectors is updated in md_finish_reshape. Then sb->data_size is set in super_1_sync based on rdev->sectors. So add md_finish_reshape in end_reshape. Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Guoqing Jiang <gqjiang@suse.com> Cc: stable@vger.kernel.org Signed-off-by: Shaohua Li <shli@fb.com>
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011067b0 |
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17-Jun-2017 |
NeilBrown <neilb@suse.com> |
blk: replace bioset_create_nobvec() with a flags arg to bioset_create() "flags" arguments are often seen as good API design as they allow easy extensibility. bioset_create_nobvec() is implemented internally as a variation in flags passed to __bioset_create(). To support future extension, make the internal structure part of the API. i.e. add a 'flags' argument to bioset_create() and discard bioset_create_nobvec(). Note that the bio_split allocations in drivers/md/raid* do not need the bvec mempool - they should have used bioset_create_nobvec(). Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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f9c79bc0 |
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07-Jun-2017 |
Mikulas Patocka <mpatocka@redhat.com> |
md: don't use flush_signals in userspace processes The function flush_signals clears all pending signals for the process. It may be used by kernel threads when we need to prepare a kernel thread for responding to signals. However using this function for an userspaces processes is incorrect - clearing signals without the program expecting it can cause misbehavior. The raid1 and raid5 code uses flush_signals in its request routine because it wants to prepare for an interruptible wait. This patch drops flush_signals and uses sigprocmask instead to block all signals (including SIGKILL) around the schedule() call. The signals are not lost, but the schedule() call won't respond to them. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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cc27b0c7 |
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05-Jun-2017 |
NeilBrown <neilb@suse.com> |
md: fix deadlock between mddev_suspend() and md_write_start() If mddev_suspend() races with md_write_start() we can deadlock with mddev_suspend() waiting for the request that is currently in md_write_start() to complete the ->make_request() call, and md_write_start() waiting for the metadata to be updated to mark the array as 'dirty'. As metadata updates done by md_check_recovery() only happen then the mddev_lock() can be claimed, and as mddev_suspend() is often called with the lock held, these threads wait indefinitely for each other. We fix this by having md_write_start() abort if mddev_suspend() is happening, and ->make_request() aborts if md_write_start() aborted. md_make_request() can detect this abort, decrease the ->active_io count, and wait for mddev_suspend(). Reported-by: Nix <nix@esperi.org.uk> Fix: 68866e425be2(MD: no sync IO while suspended) Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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4e4cbee9 |
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03-Jun-2017 |
Christoph Hellwig <hch@lst.de> |
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
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a415c0f1 |
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05-Jun-2017 |
NeilBrown <neilb@suse.com> |
md: initialise ->writes_pending in personality modules. The new per-cpu counter for writes_pending is initialised in md_alloc(), which is not called by dm-raid. So dm-raid fails when md_write_start() is called. Move the initialization to the personality modules that need it. This way it is always initialised when needed, but isn't unnecessarily initialized (requiring memory allocation) when the personality doesn't use writes_pending. Reported-by: Heinz Mauelshagen <heinzm@redhat.com> Fixes: 4ad23a976413 ("MD: use per-cpu counter for writes_pending") Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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e1539036 |
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16-May-2017 |
Nix <nix@esperi.org.uk> |
md: report sector of stripes with check mismatches This makes it possible, with appropriate filesystem support, for a sysadmin to tell what is affected by the mismatch, and whether it should be ignored (if it's inside a swap partition, for instance). We ratelimit to prevent log flooding: if there are so many mismatches that ratelimiting is necessary, the individual messages are relatively unlikely to be important (either the machine is swapping like crazy or something is very wrong with the disk). Signed-off-by: Nick Alcock <nick.alcock@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com>
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5ddf0440 |
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11-May-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: handle sync with data in write back cache Currently, sync of raid456 array cannot make progress when hitting data in writeback r5cache. This patch fixes this issue by flushing cached data of the stripe before processing the sync request. This is achived by: 1. In handle_stripe(), do not set STRIPE_SYNCING if the stripe is in write back cache; 2. In r5c_try_caching_write(), handle the stripe in sync with write through; 3. In do_release_stripe(), make stripe in sync write out and send it to the state machine. Shaohua: explictly set STRIPE_HANDLE after write out completed Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
70d466f7 |
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11-May-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: gracefully handle journal device errors for writeback mode For the raid456 with writeback cache, when journal device failed during normal operation, it is still possible to persist all data, as all pending data is still in stripe cache. However, it is necessary to handle journal failure gracefully. During journal failures, the following logic handles the graceful shutdown of journal: 1. raid5_error() marks the device as Faulty and schedules async work log->disable_writeback_work; 2. In disable_writeback_work (r5c_disable_writeback_async), the mddev is suspended, set to write through, and then resumed. mddev_suspend() flushes all cached stripes; 3. All cached stripes need to be flushed carefully to the RAID array. This patch fixes issues within the process above: 1. In r5c_update_on_rdev_error() schedule disable_writeback_work for journal failures; 2. In r5c_disable_writeback_async(), wait for MD_SB_CHANGE_PENDING, since raid5_error() updates superblock. 3. In handle_stripe(), allow stripes with data in journal (s.injournal > 0) to make progress during log_failed; 4. In delay_towrite(), if log failed only process data in the cache (skip new writes in dev->towrite); 5. In __get_priority_stripe(), process loprio_list during journal device failures. 6. In raid5_remove_disk(), wait for all cached stripes are flushed before calling log_exit(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
2214c260 |
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08-May-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
md: don't return -EAGAIN in md_allow_write for external metadata arrays This essentially reverts commit b5470dc5fc18 ("md: resolve external metadata handling deadlock in md_allow_write") with some adjustments. Since commit 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") changing array_state to 'active' does not use mddev_lock() and will not cause a deadlock with md_allow_write(). This revert simplifies userspace tools that write to sysfs attributes like "stripe_cache_size" or "consistency_policy" because it removes the need for special handling for external metadata arrays, checking for EAGAIN and retrying the write. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
3d05f3ae |
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27-Apr-2017 |
Julia Cartwright <julia@ni.com> |
md/raid5: make use of spin_lock_irq over local_irq_disable + spin_lock On mainline, there is no functional difference, just less code, and symmetric lock/unlock paths. On PREEMPT_RT builds, this fixes the following warning, seen by Alexander GQ Gerasiov, due to the sleeping nature of spinlocks. BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:993 in_atomic(): 0, irqs_disabled(): 1, pid: 58, name: kworker/u12:1 CPU: 5 PID: 58 Comm: kworker/u12:1 Tainted: G W 4.9.20-rt16-stand6-686 #1 Hardware name: Supermicro SYS-5027R-WRF/X9SRW-F, BIOS 3.2a 10/28/2015 Workqueue: writeback wb_workfn (flush-253:0) Call Trace: dump_stack+0x47/0x68 ? migrate_enable+0x4a/0xf0 ___might_sleep+0x101/0x180 rt_spin_lock+0x17/0x40 add_stripe_bio+0x4e3/0x6c0 [raid456] ? preempt_count_add+0x42/0xb0 raid5_make_request+0x737/0xdd0 [raid456] Reported-by: Alexander GQ Gerasiov <gq@redlab-i.ru> Tested-by: Alexander GQ Gerasiov <gq@redlab-i.ru> Signed-off-by: Julia Cartwright <julia@ni.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
e5bc9c3c |
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24-Apr-2017 |
Guoqing Jiang <gqjiang@suse.com> |
md: clear WantReplacement once disk is removed We can clear 'WantReplacement' flag directly no matter it's replacement existed or not since the semantic is same as before. Also since the disk is removed from array, then it is straightforward to remove 'WantReplacement' flag and the comments in raid10/5 can be removed as well. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
dd7a8f5d |
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04-Apr-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: make chunk_aligned_read() split bios more cleanly. chunk_aligned_read() currently uses fs_bio_set - which is meant for filesystems to use - and loops if multiple splits are needed, which is not best practice. As this is only used for READ requests, not writes, it is unlikely to cause a problem. However it is best to be consistent in how we split bios, and to follow the pattern used in raid1/raid10. So create a private bioset, bio_split, and use it to perform a single split, submitting the remainder to generic_make_request() for later processing. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
ae1713e2 |
|
04-Apr-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: partial parity calculation optimization In case of read-modify-write, partial partity is the same as the result of ops_run_prexor5(), so we can just copy sh->dev[pd_idx].page into sh->ppl_page instead of calculating it again. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
845b9e22 |
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04-Apr-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: use resize_stripes() when enabling or disabling ppl Use resize_stripes() instead of raid5_reset_stripe_cache() to allocate or free sh->ppl_page at runtime for all stripes in the stripe cache. raid5_reset_stripe_cache() required suspending the mddev and could deadlock because of GFP_KERNEL allocations. Move the 'newsize' check to check_reshape() to allow reallocating the stripes with the same number of disks. Allocate sh->ppl_page in alloc_stripe() instead of grow_buffers(). Pass 'struct r5conf *conf' as a parameter to alloc_stripe() because it is needed to check whether to allocate ppl_page. Add free_stripe() and use it to free stripes rather than directly call kmem_cache_free(). Also free sh->ppl_page in free_stripe(). Set MD_HAS_PPL at the end of ppl_init_log() instead of explicitly setting it in advance and add another parameter to log_init() to allow calling ppl_init_log() without the bit set. Don't try to calculate partial parity or add a stripe to log if it does not have ppl_page set. Enabling ppl can now be performed without suspending the mddev, because the log won't be used until new stripes are allocated with ppl_page. Calling mddev_suspend/resume is still necessary when disabling ppl, because we want all stripes to finish before stopping the log, but resize_stripes() can be called after mddev_resume() when ppl is no longer active. Suggested-by: NeilBrown <neilb@suse.com> Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
7471fb77 |
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02-Apr-2017 |
NeilBrown <neilb@suse.com> |
md/raid6: Fix anomily when recovering a single device in RAID6. When recoverying a single missing/failed device in a RAID6, those stripes where the Q block is on the missing device are handled a bit differently. In these cases it is easy to check that the P block is correct, so we do. This results in the P block be destroy. Consequently the P block needs to be read a second time in order to compute Q. This causes lots of seeks and hurts performance. It shouldn't be necessary to re-read P as it can be computed from the DATA. But we only compute blocks on missing devices, since c337869d9501 ("md: do not compute parity unless it is on a failed drive"). So relax the change made in that commit to allow computing of the P block in a RAID6 which it is the only missing that block. This makes RAID6 recovery run much faster as the disk just "before" the recovering device is no longer seeking back-and-forth. Reported-by-tested-by: Brad Campbell <lists2009@fnarfbargle.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
583da48e |
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29-Mar-2017 |
Dennis Yang <dennisyang@qnap.com> |
md: update slab_cache before releasing new stripes when stripes resizing When growing raid5 device on machine with small memory, there is chance that mdadm will be killed and the following bug report can be observed. The same bug could also be reproduced in linux-4.10.6. [57600.075774] BUG: unable to handle kernel NULL pointer dereference at (null) [57600.083796] IP: [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.110378] PGD 421cf067 PUD 4442d067 PMD 0 [57600.114678] Oops: 0002 [#1] SMP [57600.180799] CPU: 1 PID: 25990 Comm: mdadm Tainted: P O 4.2.8 #1 [57600.187849] Hardware name: To be filled by O.E.M. To be filled by O.E.M./MAHOBAY, BIOS QV05AR66 03/06/2013 [57600.197490] task: ffff880044e47240 ti: ffff880043070000 task.ti: ffff880043070000 [57600.204963] RIP: 0010:[<ffffffff81a6aa87>] [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.213057] RSP: 0018:ffff880043073810 EFLAGS: 00010046 [57600.218359] RAX: 0000000000000000 RBX: 000000000000000c RCX: ffff88011e296dd0 [57600.225486] RDX: 0000000000000001 RSI: ffffe8ffffcb46c0 RDI: 0000000000000000 [57600.232613] RBP: ffff880043073878 R08: ffff88011e5f8170 R09: 0000000000000282 [57600.239739] R10: 0000000000000005 R11: 28f5c28f5c28f5c3 R12: ffff880043073838 [57600.246872] R13: ffffe8ffffcb46c0 R14: 0000000000000000 R15: ffff8800b9706a00 [57600.253999] FS: 00007f576106c700(0000) GS:ffff88011e280000(0000) knlGS:0000000000000000 [57600.262078] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [57600.267817] CR2: 0000000000000000 CR3: 00000000428fe000 CR4: 00000000001406e0 [57600.274942] Stack: [57600.276949] ffffffff8114ee35 ffff880043073868 0000000000000282 000000000000eb3f [57600.284383] ffffffff81119043 ffff880043073838 ffff880043073838 ffff88003e197b98 [57600.291820] ffffe8ffffcb46c0 ffff88003e197360 0000000000000286 ffff880043073968 [57600.299254] Call Trace: [57600.301698] [<ffffffff8114ee35>] ? cache_flusharray+0x35/0xe0 [57600.307523] [<ffffffff81119043>] ? __page_cache_release+0x23/0x110 [57600.313779] [<ffffffff8114eb53>] kmem_cache_free+0x63/0xc0 [57600.319344] [<ffffffff81579942>] drop_one_stripe+0x62/0x90 [57600.324915] [<ffffffff81579b5b>] raid5_cache_scan+0x8b/0xb0 [57600.330563] [<ffffffff8111b98a>] shrink_slab.part.36+0x19a/0x250 [57600.336650] [<ffffffff8111e38c>] shrink_zone+0x23c/0x250 [57600.342039] [<ffffffff8111e4f3>] do_try_to_free_pages+0x153/0x420 [57600.348210] [<ffffffff8111e851>] try_to_free_pages+0x91/0xa0 [57600.353959] [<ffffffff811145b1>] __alloc_pages_nodemask+0x4d1/0x8b0 [57600.360303] [<ffffffff8157a30b>] check_reshape+0x62b/0x770 [57600.365866] [<ffffffff8157a4a5>] raid5_check_reshape+0x55/0xa0 [57600.371778] [<ffffffff81583df7>] update_raid_disks+0xc7/0x110 [57600.377604] [<ffffffff81592b73>] md_ioctl+0xd83/0x1b10 [57600.382827] [<ffffffff81385380>] blkdev_ioctl+0x170/0x690 [57600.388307] [<ffffffff81195238>] block_ioctl+0x38/0x40 [57600.393525] [<ffffffff811731c5>] do_vfs_ioctl+0x2b5/0x480 [57600.399010] [<ffffffff8115e07b>] ? vfs_write+0x14b/0x1f0 [57600.404400] [<ffffffff811733cc>] SyS_ioctl+0x3c/0x70 [57600.409447] [<ffffffff81a6ad97>] entry_SYSCALL_64_fastpath+0x12/0x6a [57600.415875] Code: 00 00 00 00 55 48 89 e5 8b 07 85 c0 74 04 31 c0 5d c3 ba 01 00 00 00 f0 0f b1 17 85 c0 75 ef b0 01 5d c3 90 31 c0 ba 01 00 00 00 <f0> 0f b1 17 85 c0 75 01 c3 55 89 c6 48 89 e5 e8 85 d1 63 ff 5d [57600.435460] RIP [<ffffffff81a6aa87>] _raw_spin_lock+0x7/0x20 [57600.441208] RSP <ffff880043073810> [57600.444690] CR2: 0000000000000000 [57600.448000] ---[ end trace cbc6b5cc4bf9831d ]--- The problem is that resize_stripes() releases new stripe_heads before assigning new slab cache to conf->slab_cache. If the shrinker function raid5_cache_scan() gets called after resize_stripes() starting releasing new stripes but right before new slab cache being assigned, it is possible that these new stripe_heads will be freed with the old slab_cache which was already been destoryed and that triggers this bug. Signed-off-by: Dennis Yang <dennisyang@qnap.com> Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org (4.1+) Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
48920ff2 |
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05-Apr-2017 |
Christoph Hellwig <hch@lst.de> |
block: remove the discard_zeroes_data flag Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can kill this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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#
3deff1a7 |
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05-Apr-2017 |
Christoph Hellwig <hch@lst.de> |
md: support REQ_OP_WRITE_ZEROES Copy & paste from the REQ_OP_WRITE_SAME code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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#
fbbaf700 |
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07-Apr-2017 |
NeilBrown <neilb@suse.com> |
block: trace completion of all bios. Currently only dm and md/raid5 bios trigger trace_block_bio_complete(). Now that we have bio_chain() and bio_inc_remaining(), it is not possible, in general, for a driver to know when the bio is really complete. Only bio_endio() knows that. So move the trace_block_bio_complete() call to bio_endio(). Now trace_block_bio_complete() pairs with trace_block_bio_queue(). Any bio for which a 'queue' event is traced, will subsequently generate a 'complete' event. There are a few cases where completion tracing is not wanted. 1/ If blk_update_request() has already generated a completion trace event at the 'request' level, there is no point generating one at the bio level too. In this case the bi_sector and bi_size will have changed, so the bio level event would be wrong 2/ If the bio hasn't actually been queued yet, but is being aborted early, then a trace event could be confusing. Some filesystems call bio_endio() but do not want tracing. 3/ The bio_integrity code interposes itself by replacing bi_end_io, then restoring it and calling bio_endio() again. This would produce two identical trace events if left like that. To handle these, we introduce a flag BIO_TRACE_COMPLETION and only produce the trace event when this is set. We address point 1 above by clearing the flag in blk_update_request(). We address point 2 above by only setting the flag when generic_make_request() is called. We address point 3 above by clearing the flag after generating a completion event. When bio_split() is used on a bio, particularly in blk_queue_split(), there is an extra complication. A new bio is split off the front, and may be handle directly without going through generic_make_request(). The old bio, which has been advanced, is passed to generic_make_request(), so it will trigger a trace event a second time. Probably the best result when a split happens is to see a single 'queue' event for the whole bio, then multiple 'complete' events - one for each component. To achieve this was can: - copy the BIO_TRACE_COMPLETION flag to the new bio in bio_split() - avoid generating a 'queue' event if BIO_TRACE_COMPLETION is already set. This way, the split-off bio won't create a queue event, the original won't either even if it re-submitted to generic_make_request(), but both will produce completion events, each for their own range. So if generic_make_request() is called (which generates a QUEUED event), then bi_endio() will create a single COMPLETE event for each range that the bio is split into, unless the driver has explicitly requested it not to. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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#
0bb0c105 |
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27-Mar-2017 |
Song Liu <songliubraving@fb.com> |
md/raid5: use consistency_policy to remove journal feature When journal device of an array fails, the array is forced into read-only mode. To make the array normal without adding another journal device, we need to remove journal _feature_ from the array. This patch allows remove journal _feature_ from an array, For journal existing journal should be either missing or faulty. To remove journal feature, it is necessary to remove the journal device first: mdadm --fail /dev/md0 /dev/sdb mdadm: set /dev/sdb faulty in /dev/md0 mdadm --remove /dev/md0 /dev/sdb mdadm: hot removed /dev/sdb from /dev/md0 Then the journal feature can be removed by echoing into the sysfs file: cat /sys/block/md0/md/consistency_policy journal echo resync > /sys/block/md0/md/consistency_policy cat /sys/block/md0/md/consistency_policy resync Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
3560741e |
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15-Mar-2017 |
Zhilong Liu <zlliu@suse.com> |
md: fix several trivial typos in comments Signed-off-by: Zhilong Liu <zlliu@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
84dd97a6 |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: don't test ->writes_pending in raid5_remove_disk This test on ->writes_pending cannot be safe as the counter can be incremented at any moment and cannot be locked against. Change it to test conf->active_stripes, which at least can be locked against. More changes are still needed. A future patch will change ->writes_pending, and testing it here will be very inconvenient. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
97d53438 |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
Revert "md/raid5: limit request size according to implementation limits" This reverts commit e8d7c33232e5fdfa761c3416539bc5b4acd12db5. Now that raid5 doesn't abuse bi_phys_segments any more, we no longer need to impose these limits. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
0472a42b |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: remove over-loading of ->bi_phys_segments. When a read request, which bypassed the cache, fails, we need to retry it through the cache. This involves attaching it to a sequence of stripe_heads, and it may not be possible to get all the stripe_heads we need at once. We do what we can, and record how far we got in ->bi_phys_segments so we can pick up again later. There is only ever one bio which may have a non-zero offset stored in ->bi_phys_segments, the one that is either active in the single thread which calls retry_aligned_read(), or is in conf->retry_read_aligned waiting for retry_aligned_read() to be called again. So we only need to store one offset value. This can be in a local variable passed between remove_bio_from_retry() and retry_aligned_read(), or in the r5conf structure next to the ->retry_read_aligned pointer. Storing it there allows the last usage of ->bi_phys_segments to be removed from md/raid5.c. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
016c76ac |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: use bio_inc_remaining() instead of repurposing bi_phys_segments as a counter md/raid5 needs to keep track of how many stripe_heads are processing a bio so that it can delay calling bio_endio() until all stripe_heads have completed. It currently uses 16 bits of ->bi_phys_segments for this purpose. 16 bits is only enough for 256M requests, and it is possible for a single bio to be larger than this, which causes problems. Also, the bio struct contains a larger counter, __bi_remaining, which has a purpose very similar to the purpose of our counter. So stop using ->bi_phys_segments, and instead use __bi_remaining. This means we don't need to initialize the counter, as our caller initializes it to '1'. It also means we can call bio_endio() directly as it tests this counter internally. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
bd83d0a2 |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: call bio_endio() directly rather than queueing for later. We currently gather bios that need to be returned into a bio_list and call bio_endio() on them all together. The original reason for this was to avoid making the calls while holding a spinlock. Locking has changed a lot since then, and that reason is no longer valid. So discard return_io() and various return_bi lists, and just call bio_endio() directly as needed. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
16d997b7 |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: simplfy delaying of writes while metadata is updated. If a device fails during a write, we must ensure the failure is recorded in the metadata before the completion of the write is acknowleged. Commit c3cce6cda162 ("md/raid5: ensure device failure recorded before write request returns.") added code for this, but it was unnecessarily complicated. We already had similar functionality for handling updates to the bad-block-list, thanks to Commit de393cdea66c ("md: make it easier to wait for bad blocks to be acknowledged.") So revert most of the former commit, and instead avoid collecting completed writes if MD_CHANGE_PENDING is set. raid5d() will then flush the metadata and retry the stripe_head. As this change can leave a stripe_head ready for handling immediately after handle_active_stripes() returns, we change raid5_do_work() to pause when MD_CHANGE_PENDING is set, so that it doesn't spin. We check MD_CHANGE_PENDING *after* analyse_stripe() as it could be set asynchronously. After analyse_stripe(), we have collected stable data about the state of devices, which will be used to make decisions. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
49728050 |
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14-Mar-2017 |
NeilBrown <neilb@suse.com> |
md/raid5: use md_write_start to count stripes, not bios We use md_write_start() to increase the count of pending writes, and md_write_end() to decrement the count. We currently count bios submitted to md/raid5. Change it count stripe_heads that a WRITE bio has been attached to. So now, raid5_make_request() calls md_write_start() and then md_write_end() to keep the count elevated during the setup of the request. add_stripe_bio() calls md_write_start() for each stripe_head, and the completion routines always call md_write_end(), instead of only calling it when raid5_dec_bi_active_stripes() returns 0. make_discard_request also calls md_write_start/end(). The parallel between md_write_{start,end} and use of bi_phys_segments can be seen in that: Whenever we set bi_phys_segments to 1, we now call md_write_start. Whenever we increment it on non-read requests with raid5_inc_bi_active_stripes(), we now call md_write_start(). Whenever we decrement bi_phys_segments on non-read requsts with raid5_dec_bi_active_stripes(), we now call md_write_end(). This reduces our dependence on keeping a per-bio count of active stripes in bi_phys_segments. md_write_inc() is added which parallels md_write_start(), but requires that a write has already been started, and is certain never to sleep. This can be used inside a spinlocked region when adding to a write request. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
ba903a3e |
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09-Mar-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: runtime PPL enabling or disabling Allow writing to 'consistency_policy' attribute when the array is active. Add a new function 'change_consistency_policy' to the md_personality operations structure to handle the change in the personality code. Values "ppl" and "resync" are accepted and turn PPL on and off respectively. When enabling PPL its location and size should first be set using 'ppl_sector' and 'ppl_size' attributes and a valid PPL header should be written at this location on each member device. Enabling or disabling PPL is performed under a suspended array. The raid5_reset_stripe_cache function frees the stripe cache and allocates it again in order to allocate or free the ppl_pages for the stripes in the stripe cache. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
6358c239 |
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09-Mar-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: support disk hot add/remove with PPL Add a function to modify the log by removing an rdev when a drive fails or adding when a spare/replacement is activated as a raid member. Removing a disk just clears the child log rdev pointer. No new stripes will be accepted for this child log in ppl_write_stripe() and running io units will be processed without writing PPL to the device. Adding a disk sets the child log rdev pointer and writes an empty PPL header. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
4536bf9b |
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09-Mar-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: load and recover the log Load the log from each disk when starting the array and recover if the array is dirty. The initial empty PPL is written by mdadm. When loading the log we verify the header checksum and signature. For external metadata arrays the signature is verified in userspace, so here we read it from the header, verifying only if it matches on all disks, and use it later when writing PPL. In addition to the header checksum, each header entry also contains a checksum of its partial parity data. If the header is valid, recovery is performed for each entry until an invalid entry is found. If the array is not degraded and recovery using PPL fully succeeds, there is no need to resync the array because data and parity will be consistent, so in this case resync will be disabled. Due to compatibility with IMSM implementations on other systems, we can't assume that the recovery data block size is always 4K. Writes generated by MD raid5 don't have this issue, but when recovering PPL written in other environments it is possible to have entries with 512-byte sector granularity. The recovery code takes this into account and also the logical sector size of the underlying drives. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
3418d036 |
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09-Mar-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5-ppl: Partial Parity Log write logging implementation Implement the calculation of partial parity for a stripe and PPL write logging functionality. The description of PPL is added to the documentation. More details can be found in the comments in raid5-ppl.c. Attach a page for holding the partial parity data to stripe_head. Allocate it only if mddev has the MD_HAS_PPL flag set. Partial parity is the xor of not modified data chunks of a stripe and is calculated as follows: - reconstruct-write case: xor data from all not updated disks in a stripe - read-modify-write case: xor old data and parity from all updated disks in a stripe Implement it using the async_tx API and integrate into raid_run_ops(). It must be called when we still have access to old data, so do it when STRIPE_OP_BIODRAIN is set, but before ops_run_prexor5(). The result is stored into sh->ppl_page. Partial parity is not meaningful for full stripe write and is not stored in the log or used for recovery, so don't attempt to calculate it when stripe has STRIPE_FULL_WRITE. Put the PPL metadata structures to md_p.h because userspace tools (mdadm) will also need to read/write PPL. Warn about using PPL with enabled disk volatile write-back cache for now. It can be removed once disk cache flushing before writing PPL is implemented. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
ff875738 |
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09-Mar-2017 |
Artur Paszkiewicz <artur.paszkiewicz@intel.com> |
raid5: separate header for log functions Move raid5-cache declarations from raid5.h to raid5-log.h, add inline wrappers for functions which will be shared with ppl and use them in raid5 core instead of direct calls to raid5-cache. Remove unused parameter from r5c_cache_data(), move two duplicated pr_debug() calls to r5l_init_log(). Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
aaf9f12e |
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03-Mar-2017 |
Shaohua Li <shli@fb.com> |
md/raid5: sort bios Previous patch (raid5: only dispatch IO from raid5d for harddisk raid) defers IO dispatching. The goal is to create better IO pattern. At that time, we don't sort the deffered IO and hope the block layer can do IO merge and sort. Now the raid5-cache writeback could create large amount of bios. And if we enable muti-thread for stripe handling, we can't control when to dispatch IO to raid disks. In a lot of time, we are dispatching IO which block layer can't do merge effectively. This patch moves further for the IO dispatching defer. We accumulate bios, but we don't dispatch all the bios after a threshold is met. This 'dispatch partial portion of bios' stragety allows bios coming in a large time window are sent to disks together. At the dispatching time, there is large chance the block layer can merge the bios. To make this more effective, we dispatch IO in ascending order. This increases request merge chance and reduces disk seek. Signed-off-by: Shaohua Li <shli@fb.com>
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#
535ae4eb |
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15-Feb-2017 |
Shaohua Li <shli@fb.com> |
md/raid5: prioritize stripes for writeback In raid5-cache writeback mode, we have two types of stripes to handle. - stripes which aren't cached yet - stripes which are cached and flushing out to raid disks Upperlayer is more sensistive to latency of the first type of stripes generally. But we only one handle list for all these stripes, where the two types of stripes are mixed together. When reclaim flushes a lot of stripes, the first type of stripes could be noticeably delayed. On the other hand, if the log space is tight, we'd like to handle the second type of stripes faster and free log space. This patch destinguishes the two types stripes. They are added into different handle list. When we try to get a stripe to handl, we prefer the first type of stripes unless log space is tight. This should have no impact for !writeback case. Signed-off-by: Shaohua Li <shli@fb.com>
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#
0977762f |
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13-Mar-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: fix set_syndrome_sources() for data in cache Before this patch, device InJournal will be included in prexor (SYNDROME_SRC_WANT_DRAIN) but not in reconstruct (SYNDROME_SRC_WRITTEN). So it will break parity calculation. With srctype == SYNDROME_SRC_WRITTEN, we need include both dev with non-null ->written and dev with R5_InJournal. This fixes logic in 1e6d690(md/r5cache: caching phase of r5cache) Cc: stable@vger.kernel.org (v4.10+) Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
c9483634 |
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23-Feb-2017 |
Guoqing Jiang <gqjiang@suse.com> |
md: move funcs from pers->resize to update_size raid1_resize and raid5_resize should also check the mddev->queue if run underneath dm-raid. And both set_capacity and revalidate_disk are used in pers->resize such as raid1, raid10 and raid5. So move them from personality file to common code. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
3f07c014 |
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08-Feb-2017 |
Ingo Molnar <mingo@kernel.org> |
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
eae8263f |
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14-Feb-2017 |
Byungchul Park <byungchul.park@lge.com> |
md/raid5: Don't reinvent the wheel but use existing llist API Although llist provides proper APIs, they are not used. Make them used. Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
d7a10308 |
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14-Feb-2017 |
Ming Lei <tom.leiming@gmail.com> |
md: fast clone bio in bio_clone_mddev() Firstly bio_clone_mddev() is used in raid normal I/O and isn't in resync I/O path. Secondly all the direct access to bvec table in raid happens on resync I/O except for write behind of raid1, in which we still use bio_clone() for allocating new bvec table. So this patch replaces bio_clone() with bio_clone_fast() in bio_clone_mddev(). Also kill bio_clone_mddev() and call bio_clone_fast() directly, as suggested by Christoph Hellwig. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
e33fbb9c |
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10-Feb-2017 |
Shaohua Li <shli@fb.com> |
md/raid5-cache: exclude reclaiming stripes in reclaim check stripes which are being reclaimed are still accounted into cached stripes. The reclaim takes time. r5c_do_reclaim isn't aware of the stripes and does unnecessary stripe reclaim. In practice, I saw one stripe is reclaimed one time. This will cause bad IO pattern. Fixing this by excluding the reclaing stripes in the check. Cc: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
39b99586 |
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24-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: improve journal device efficiency It is important to be able to flush all stripes in raid5-cache. Therefore, we need reserve some space on the journal device for these flushes. If flush operation includes pending writes to the stripe, we need to reserve (conf->raid_disk + 1) pages per stripe for the flush out. This reduces the efficiency of journal space. If we exclude these pending writes from flush operation, we only need (conf->max_degraded + 1) pages per stripe. With this patch, when log space is critical (R5C_LOG_CRITICAL=1), pending writes will be excluded from stripe flush out. Therefore, we can reduce reserved space for flush out and thus improve journal device efficiency. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
03b047f4 |
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11-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: enable chunk_aligned_read with write back cache Chunk aligned read significantly reduces CPU usage of raid456. However, it is not safe to fully bypass the write back cache. This patch enables chunk aligned read with write back cache. For chunk aligned read, we track stripes in write back cache at a bigger granularity, "big_stripe". Each chunk may contain more than one stripe (for example, a 256kB chunk contains 64 4kB-page, so this chunk contain 64 stripes). For chunk_aligned_read, these stripes are grouped into one big_stripe, so we only need one lookup for the whole chunk. For each big_stripe, struct big_stripe_info tracks how many stripes of this big_stripe are in the write back cache. We count how many stripes of this big_stripe are in the write back cache. These counters are tracked in a radix tree (big_stripe_tree). r5c_tree_index() is used to calculate keys for the radix tree. chunk_aligned_read() calls r5c_big_stripe_cached() to look up big_stripe of each chunk in the tree. If this big_stripe is in the tree, chunk_aligned_read() aborts. This look up is protected by rcu_read_lock(). It is necessary to remember whether a stripe is counted in big_stripe_tree. Instead of adding new flag, we reuses existing flags: STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE. If either of these two flags are set, the stripe is counted in big_stripe_tree. This requires moving set_bit(STRIPE_R5C_PARTIAL_STRIPE) to r5c_try_caching_write(); and moving clear_bit of STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE to r5c_finish_stripe_write_out(). Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
765d704d |
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04-Jan-2017 |
Shaohua Li <shli@fb.com> |
raid5: only dispatch IO from raid5d for harddisk raid We made raid5 stripe handling multi-thread before. It works well for SSD. But for harddisk, the multi-threading creates more disk seek, so not always improve performance. For several hard disks based raid5, multi-threading is required as raid5d becames a bottleneck especially for sequential write. To overcome the disk seek issue, we only dispatch IO from raid5d if the array is harddisk based. Other threads can still handle stripes, but can't dispatch IO. Idealy, we should control IO dispatching order according to IO position interrnally. Right now we still depend on block layer, which isn't very efficient sometimes though. My setup has 9 harddisks, each disk can do around 180M/s sequential write. So in theory, the raid5 can do 180 * 8 = 1440M/s sequential write. The test machine uses an ATOM CPU. I measure sequential write with large iodepth bandwidth to raid array: without patch: ~600M/s without patch and group_thread_cnt=4: 750M/s with patch and group_thread_cnt=4: 950M/s with patch, group_thread_cnt=4, skip_copy=1: 1150M/s We are pretty close to the maximum bandwidth in the large iodepth iodepth case. The performance gap of small iodepth sequential write between software raid and theory value is still very big though, because we don't have an efficient pipeline. Cc: NeilBrown <neilb@suse.com> Cc: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
dc3b17cc |
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02-Feb-2017 |
Jan Kara <jack@suse.cz> |
block: Use pointer to backing_dev_info from request_queue We will want to have struct backing_dev_info allocated separately from struct request_queue. As the first step add pointer to backing_dev_info to request_queue and convert all users touching it. No functional changes in this patch. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
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#
2e38a37f |
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24-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: disable write back for degraded array write-back cache in degraded mode introduces corner cases to the array. Although we try to cover all these corner cases, it is safer to just disable write-back cache when the array is in degraded mode. In this patch, we disable writeback cache for degraded mode: 1. On device failure, if the array enters degraded mode, raid5_error() will submit async job r5c_disable_writeback_async to disable writeback; 2. In r5c_journal_mode_store(), it is invalid to enable writeback in degraded mode; 3. In r5c_try_caching_write(), stripes with s->failed>0 will be handled in write-through mode. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
07e83364 |
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23-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: shift complex rmw from read path to write path Write back cache requires a complex RMW mechanism, where old data is read into dev->orig_page for prexor, and then xor is done with dev->page. This logic is already implemented in the write path. However, current read path is not awared of this requirement. When the array is optimal, the RMW is not required, as the data are read from raid disks. However, when the target stripe is degraded, complex RMW is required to generate right data. To keep read path as clean as possible, we handle read path by flushing degraded, in-journal stripes before processing reads to missing dev. Specifically, when there is read requests to a degraded stripe with data in journal, handle_stripe_fill() calls r5c_make_stripe_write_out() and exits. Then handle_stripe_dirtying() will do the complex RMW and flush the stripe to RAID disks. After that, read requests are handled. There is one more corner case when there is non-overwrite bio for the missing (or out of sync) dev. handle_stripe_dirtying() will not be able to process the non-overwrite bios without constructing the data in handle_stripe_fill(). This is fixed by delaying non-overwrite bios in handle_stripe_dirtying(). So handle_stripe_fill() works on these bios after the stripe is flushed to raid disks. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
ba02684d |
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12-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/raid5: move comment of fetch_block to right location Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
86aa1397 |
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12-Jan-2017 |
Song Liu <songliubraving@fb.com> |
md/r5cache: read data into orig_page for prexor of cached data With write back cache, we use orig_page to do prexor. This patch makes sure we read data into orig_page for it. Flag R5_OrigPageUPTDODATE is added to show whether orig_page has the latest data from raid disk. We introduce a helper function uptodate_for_rmw() to simplify the a couple conditions in handle_stripe_dirtying(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
32cd7cbb |
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06-Jan-2017 |
Jes Sorensen <Jes.Sorensen@redhat.com> |
md/raid5: Use correct IS_ERR() variation on pointer check This fixes a build error on certain architectures, such as ppc64. Fixes: 6995f0b247e("md: takeover should clear unrelated bits") Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
394ed8e4 |
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04-Jan-2017 |
Shaohua Li <shli@fb.com> |
md: cleanup mddev flag clear for takeover Commit 6995f0b (md: takeover should clear unrelated bits) clear unrelated bits, but it's quite fragile. To avoid error in the future, define a macro for unsupported mddev flags for each raid type and use it to clear unsupported mddev flags. This should be less error-prone. Suggested-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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2953079c |
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08-Dec-2016 |
Shaohua Li <shli@fb.com> |
md: separate flags for superblock changes The mddev->flags are used for different purposes. There are a lot of places we check/change the flags without masking unrelated flags, we could check/change unrelated flags. These usage are most for superblock write, so spearate superblock related flags. This should make the code clearer and also fix real bugs. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
6995f0b2 |
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08-Dec-2016 |
Shaohua Li <shli@fb.com> |
md: takeover should clear unrelated bits When we change level from raid1 to raid5, the MD_FAILFAST_SUPPORTED bit will be accidentally set, but raid5 doesn't support it. The same is true for the MD_HAS_JOURNAL bit. Fix: 46533ff (md: Use REQ_FAILFAST_* on metadata writes where appropriate) Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
e8d7c332 |
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27-Nov-2016 |
Konstantin Khlebnikov <koct9i@gmail.com> |
md/raid5: limit request size according to implementation limits Current implementation employ 16bit counter of active stripes in lower bits of bio->bi_phys_segments. If request is big enough to overflow this counter bio will be completed and freed too early. Fortunately this not happens in default configuration because several other limits prevent that: stripe_cache_size * nr_disks effectively limits count of active stripes. And small max_sectors_kb at lower disks prevent that during normal read/write operations. Overflow easily happens in discard if it's enabled by module parameter "devices_handle_discard_safely" and stripe_cache_size is set big enough. This patch limits requests size with 256Mb - 8Kb to prevent overflows. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Shaohua Li <shli@kernel.org> Cc: Neil Brown <neilb@suse.com> Cc: stable@vger.kernel.org Signed-off-by: Shaohua Li <shli@fb.com>
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#
d7bd398e |
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23-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: handle alloc_page failure RMW of r5c write back cache uses an extra page to store old data for prexor. handle_stripe_dirtying() allocates this page by calling alloc_page(). However, alloc_page() may fail. To handle alloc_page() failures, this patch adds an extra page to disk_info. When alloc_page fails, handle_stripe() trys to use these pages. When these pages are used by other stripe (R5C_EXTRA_PAGE_IN_USE), the stripe is added to delayed_list. Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
3a83f467 |
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22-Nov-2016 |
Ming Lei <tom.leiming@gmail.com> |
block: bio: pass bvec table to bio_init() Some drivers often use external bvec table, so introduce this helper for this case. It is always safe to access the bio->bi_io_vec in this way for this case. After converting to this usage, it will becomes a bit easier to evaluate the remaining direct access to bio->bi_io_vec, so it can help to prepare for the following multipage bvec support. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Fixed up the new O_DIRECT cases. Signed-off-by: Jens Axboe <axboe@fb.com>
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#
3bddb7f8 |
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18-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: handle FLUSH and FUA With raid5 cache, we committing data from journal device. When there is flush request, we need to flush journal device's cache. This was not needed in raid5 journal, because we will flush the journal before committing data to raid disks. This is similar to FUA, except that we also need flush journal for FUA. Otherwise, corruptions in earlier meta data will stop recovery from reaching FUA data. slightly changed the code by Shaohua Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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5aabf7c4 |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: r5cache recovery: part 2 1. In previous patch, we: - add new data to r5l_recovery_ctx - add new functions to recovery write-back cache The new functions are not used in this patch, so this patch does not change the behavior of recovery. 2. In this patchpatch, we: - modify main recovery procedure r5l_recovery_log() to call new functions - remove old functions Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
2c7da14b |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: sysfs entry journal_mode With write cache, journal_mode is the knob to switch between write-back and write-through. Below is an example: root@virt-test:~/# cat /sys/block/md0/md/journal_mode [write-through] write-back root@virt-test:~/# echo write-back > /sys/block/md0/md/journal_mode root@virt-test:~/# cat /sys/block/md0/md/journal_mode write-through [write-back] Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
a39f7afd |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: write-out phase and reclaim support There are two limited resources, stripe cache and journal disk space. For better performance, we priotize reclaim of full stripe writes. To free up more journal space, we free earliest data on the journal. In current implementation, reclaim happens when: 1. Periodically (every R5C_RECLAIM_WAKEUP_INTERVAL, 30 seconds) reclaim if there is no reclaim in the past 5 seconds. 2. when there are R5C_FULL_STRIPE_FLUSH_BATCH (256) cached full stripes, or cached stripes is enough for a full stripe (chunk size / 4k) (r5c_check_cached_full_stripe) 3. when there is pressure on stripe cache (r5c_check_stripe_cache_usage) 4. when there is pressure on journal space (r5l_write_stripe, r5c_cache_data) r5c_do_reclaim() contains new logic of reclaim. For stripe cache: When stripe cache pressure is high (more than 3/4 stripes are cached, or there is empty inactive lists), flush all full stripe. If fewer than R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2) full stripes are flushed, flush some paritial stripes. When stripe cache pressure is moderate (1/2 to 3/4 of stripes are cached), flush all full stripes. For log space: To avoid deadlock due to log space, we need to reserve enough space to flush cached data. The size of required log space depends on total number of cached stripes (stripe_in_journal_count). In current implementation, the writing-out phase automatically include pending data writes with parity writes (similar to write through case). Therefore, we need up to (conf->raid_disks + 1) pages for each cached stripe (1 page for meta data, raid_disks pages for all data and parity). r5c_log_required_to_flush_cache() calculates log space required to flush cache. In the following, we refer to the space calculated by r5c_log_required_to_flush_cache() as reclaim_required_space. Two flags are added to r5conf->cache_state: R5C_LOG_TIGHT and R5C_LOG_CRITICAL. R5C_LOG_TIGHT is set when free space on the log device is less than 3x of reclaim_required_space. R5C_LOG_CRITICAL is set when free space on the log device is less than 2x of reclaim_required_space. r5c_cache keeps all data in cache (not fully committed to RAID) in a list (stripe_in_journal_list). These stripes are in the order of their first appearance on the journal. So the log tail (last_checkpoint) should point to the journal_start of the first item in the list. When R5C_LOG_TIGHT is set, r5l_reclaim_thread starts flushing out stripes at the head of stripe_in_journal. When R5C_LOG_CRITICAL is set, the state machine only writes data that are already in the log device (in stripe_in_journal_list). This patch includes a fix to improve performance by Shaohua Li <shli@fb.com>. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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#
1e6d690b |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: caching phase of r5cache As described in previous patch, write back cache operates in two phases: caching and writing-out. The caching phase works as: 1. write data to journal (r5c_handle_stripe_dirtying, r5c_cache_data) 2. call bio_endio (r5c_handle_data_cached, r5c_return_dev_pending_writes). Then the writing-out phase is as: 1. Mark the stripe as write-out (r5c_make_stripe_write_out) 2. Calcualte parity (reconstruct or RMW) 3. Write parity (and maybe some other data) to journal device 4. Write data and parity to RAID disks This patch implements caching phase. The cache is integrated with stripe cache of raid456. It leverages code of r5l_log to write data to journal device. Writing-out phase of the cache is implemented in the next patch. With r5cache, write operation does not wait for parity calculation and write out, so the write latency is lower (1 write to journal device vs. read and then write to raid disks). Also, r5cache will reduce RAID overhead (multipile IO due to read-modify-write of parity) and provide more opportunities of full stripe writes. This patch adds 2 flags to stripe_head.state: - STRIPE_R5C_PARTIAL_STRIPE, - STRIPE_R5C_FULL_STRIPE, Instead of inactive_list, stripes with cached data are tracked in r5conf->r5c_full_stripe_list and r5conf->r5c_partial_stripe_list. STRIPE_R5C_FULL_STRIPE and STRIPE_R5C_PARTIAL_STRIPE are flags for stripes in these lists. Note: stripes in r5c_full/partial_stripe_list are not considered as "active". For RMW, the code allocates an extra page for each data block being updated. This is stored in r5dev->orig_page and the old data is read into it. Then the prexor calculation subtracts ->orig_page from the parity block, and the reconstruct calculation adds the ->page data back into the parity block. r5cache naturally excludes SkipCopy. When the array has write back cache, async_copy_data() will not skip copy. There are some known limitations of the cache implementation: 1. Write cache only covers full page writes (R5_OVERWRITE). Writes of smaller granularity are write through. 2. Only one log io (sh->log_io) for each stripe at anytime. Later writes for the same stripe have to wait. This can be improved by moving log_io to r5dev. 3. With writeback cache, read path must enter state machine, which is a significant bottleneck for some workloads. 4. There is no per stripe checkpoint (with r5l_payload_flush) in the log, so recovery code has to replay more than necessary data (sometimes all the log from last_checkpoint). This reduces availability of the array. This patch includes a fix proposed by ZhengYuan Liu <liuzhengyuan@kylinos.cn> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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2ded3703 |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: State machine for raid5-cache write back mode This patch adds state machine for raid5-cache. With log device, the raid456 array could operate in two different modes (r5c_journal_mode): - write-back (R5C_MODE_WRITE_BACK) - write-through (R5C_MODE_WRITE_THROUGH) Existing code of raid5-cache only has write-through mode. For write-back cache, it is necessary to extend the state machine. With write-back cache, every stripe could operate in two different phases: - caching - writing-out In caching phase, the stripe handles writes as: - write to journal - return IO In writing-out phase, the stripe behaviors as a stripe in write through mode R5C_MODE_WRITE_THROUGH. STRIPE_R5C_CACHING is added to sh->state to differentiate caching and writing-out phase. Please note: this is a "no-op" patch for raid5-cache write-through mode. The following detailed explanation is copied from the raid5-cache.c: /* * raid5 cache state machine * * With rhe RAID cache, each stripe works in two phases: * - caching phase * - writing-out phase * * These two phases are controlled by bit STRIPE_R5C_CACHING: * if STRIPE_R5C_CACHING == 0, the stripe is in writing-out phase * if STRIPE_R5C_CACHING == 1, the stripe is in caching phase * * When there is no journal, or the journal is in write-through mode, * the stripe is always in writing-out phase. * * For write-back journal, the stripe is sent to caching phase on write * (r5c_handle_stripe_dirtying). r5c_make_stripe_write_out() kicks off * the write-out phase by clearing STRIPE_R5C_CACHING. * * Stripes in caching phase do not write the raid disks. Instead, all * writes are committed from the log device. Therefore, a stripe in * caching phase handles writes as: * - write to log device * - return IO * * Stripes in writing-out phase handle writes as: * - calculate parity * - write pending data and parity to journal * - write data and parity to raid disks * - return IO for pending writes */ Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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937621c3 |
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17-Nov-2016 |
Song Liu <songliubraving@fb.com> |
md/r5cache: move some code to raid5.h Move some define and inline functions to raid5.h, so they can be used in raid5-cache.c Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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cc6167b4 |
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01-Nov-2016 |
NeilBrown <neilb@suse.com> |
md/raid5: change printk() to pr_*() Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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7adb072c |
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26-Oct-2016 |
Tomasz Majchrzak <tomasz.majchrzak@intel.com> |
raid5: revert commit 11367799f3d1 Revert commit 11367799f3d1 ("md: Prevent IO hold during accessing to faulty raid5 array") as it doesn't comply with commit c3cce6cda162 ("md/raid5: ensure device failure recorded before write request returns."). That change is not required anymore as the problem is resolved by commit 16f889499a52 ("md: report 'write_pending' state when array in sync") - read request is stuck as array state is not reported correctly via sysfs attribute. Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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70fd7614 |
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01-Nov-2016 |
Christoph Hellwig <hch@lst.de> |
block,fs: use REQ_* flags directly Remove the WRITE_* and READ_SYNC wrappers, and just use the flags directly. Where applicable this also drops usage of the bio_set_op_attrs wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
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30c89465 |
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21-Sep-2016 |
Shaohua Li <shli@fb.com> |
raid5: handle register_shrinker failure register_shrinker() now can fail. When it happens, shrinker.nr_deferred is null. We use it to determine if unregister_shrinker is required. Signed-off-by: Shaohua Li <shli@fb.com>
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6a0f53ff |
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19-Sep-2016 |
Chao Yu <chao@kernel.org> |
raid5: fix to detect failure of register_shrinker register_shrinker can fail after commit 1d3d4437eae1 ("vmscan: per-node deferred work"), we should detect the failure of it, otherwise we may fail to register shrinker after raid5 configuration was setup successfully. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Shaohua Li <shli@fb.com>
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1dffdddd |
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08-Sep-2016 |
Shaohua Li <shli@fb.com> |
raid5: allow arbitrary max_hw_sectors raid5 will split bio to proper size internally, there is no point to use underlayer disk's max_hw_sectors. In my qemu system, without the change, the raid5 only receives 128k size bio, which reduces the chance of bio merge sending to underlayer disks. Signed-off-by: Shaohua Li <shli@fb.com>
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c9445555 |
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08-Sep-2016 |
Shaohua Li <shli@fb.com> |
raid5: fix a small race condition commit 5f9d1fde7d54a5(raid5: fix memory leak of bio integrity data) moves bio_reset to bio_endio. But it introduces a small race condition. It does bio_reset after raid5_release_stripe, which could make the stripe reusable and hence reuse the bio just before bio_reset. Moving bio_reset before raid5_release_stripe is called should fix the race. Reported-and-tested-by: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Signed-off-by: Shaohua Li <shli@fb.com>
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29c6d1bb |
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18-Aug-2016 |
Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
md/raid5: Convert to hotplug state machine Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Neil Brown <neilb@suse.com> Cc: linux-raid@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160818125731.27256-10-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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ad5b0f76 |
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30-Aug-2016 |
Shaohua Li <shli@fb.com> |
raid5: guarantee enough stripes to avoid reshape hang If there aren't enough stripes, reshape will hang. We have a check for this in new reshape, but miss it for reshape resume, hence we could see hang in reshape resume. This patch forces enough stripes existed if reshape resumes. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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45c91d80 |
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22-Aug-2016 |
Shaohua Li <shli@fb.com> |
raid5: avoid unnecessary bio data set bio_reset doesn't change bi_io_vec and bi_max_vecs, so we don't need to set them every time. bi_private will be set before the bio is dispatched. Signed-off-by: Shaohua Li <shli@fb.com>
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5f9d1fde |
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22-Aug-2016 |
Shaohua Li <shli@fb.com> |
raid5: fix memory leak of bio integrity data Yi reported a memory leak of raid5 with DIF/DIX enabled disks. raid5 doesn't alloc/free bio, instead it reuses bios. There are two issues in current code: 1. the code calls bio_init (from init_stripe->raid5_build_block->bio_init) then bio_reset (ops_run_io). The bio is reused, so likely there is integrity data attached. bio_init will clear a pointer to integrity data and makes bio_reset can't release the data 2. bio_reset is called before dispatching bio. After bio is finished, it's possible we don't free bio's integrity data (eg, we don't call bio_reset again) Both issues will cause memory leak. The patch moves bio_init to stripe creation and bio_reset to bio end io. This will fix the two issues. Reported-by: Yi Zhang <yizhan@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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486b0f7b |
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19-Aug-2016 |
Song Liu <songliubraving@fb.com> |
r5cache: set MD_JOURNAL_CLEAN correctly Currently, the code sets MD_JOURNAL_CLEAN when the array has MD_FEATURE_JOURNAL and the recovery_cp is MaxSector. The array will be MD_JOURNAL_CLEAN even if the journal device is missing. With this patch, the MD_JOURNAL_CLEAN is only set when the journal device presents. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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1eff9d32 |
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05-Aug-2016 |
Jens Axboe <axboe@fb.com> |
block: rename bio bi_rw to bi_opf Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower portion and the op code in the higher portions. This means that old code that relies on manually setting bi_rw is most likely going to be broken. Instead of letting that brokeness linger, rename the member, to force old and out-of-tree code to break at compile time instead of at runtime. No intended functional changes in this commit. Signed-off-by: Jens Axboe <axboe@fb.com>
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11367799 |
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03-Aug-2016 |
Alexey Obitotskiy <aleksey.obitotskiy@intel.com> |
md: Prevent IO hold during accessing to faulty raid5 array After array enters in faulty state (e.g. number of failed drives becomes more then accepted for raid5 level) it sets error flags (one of this flags is MD_CHANGE_PENDING). For internal metadata arrays MD_CHANGE_PENDING cleared into md_update_sb, but not for external metadata arrays. MD_CHANGE_PENDING flag set prevents to finish all new or non-finished IOs to array and hold them in pending state. In some cases this can leads to deadlock situation. For example, we have faulty array (2 of 4 drives failed) and udev handle array state changes and blkid started (or other userspace application that used array to read/write) but unable to finish reads due to IO hold. At the same time we unable to get exclusive access to array (to stop array in our case) because another external application still use this array. Fix makes possible to return IO with errors immediately. So external application can finish working with array and give exclusive access to other applications to perform required management actions with array. Signed-off-by: Alexey Obitotskiy <aleksey.obitotskiy@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
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ff00d3b4 |
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28-Jul-2016 |
ZhengYuan Liu <liuzhengyuan@kylinos.cn> |
raid5: fix incorrectly counter of conf->empty_inactive_list_nr The counter conf->empty_inactive_list_nr is only used for determine if the raid5 is congested which is deal with in function raid5_congested(). It was increased in get_free_stripe() when conf->inactive_list got to be empty and decreased in release_inactive_stripe_list() when splice temp_inactive_list to conf->inactive_list. However, this may have a problem when raid5_get_active_stripe or stripe_add_to_batch_list was called, because these two functions may call list_del_init(&sh->lru) to delete sh from "conf->inactive_list + hash" which may cause "conf->inactive_list + hash" to be empty when atomic_inc_not_zero(&sh->count) got false. So a check should be done at these two point and increase empty_inactive_list_nr accordingly. Otherwise the counter may get to be negative number which would influence async readahead from VFS. Signed-off-by: ZhengYuan Liu <liuzhengyuan@kylinos.cn> Signed-off-by: Shaohua Li <shli@fb.com>
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70246286 |
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19-Jul-2016 |
Christoph Hellwig <hch@lst.de> |
block: get rid of bio_rw and READA These two are confusing leftover of the old world order, combining values of the REQ_OP_ and REQ_ namespaces. For callers that don't special case we mostly just replace bi_rw with bio_data_dir or op_is_write, except for the few cases where a switch over the REQ_OP_ values makes more sense. Any check for READA is replaced with an explicit check for REQ_RAHEAD. Also remove the READA alias for REQ_RAHEAD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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d787be40 |
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02-Jun-2016 |
NeilBrown <neilb@suse.com> |
md: reduce the number of synchronize_rcu() calls when multiple devices fail. Every time a device is removed with ->hot_remove_disk() a synchronize_rcu() call is made which can delay several milliseconds in some case. If lots of devices fail at once - as could happen with a large RAID10 where one set of devices are removed all at once - these delays can add up to be very inconcenient. As failure is not reversible we can check for that first, setting a separate flag if it is found, and then all synchronize_rcu() once for all the flagged devices. Then ->hot_remove_disk() function can skip the synchronize_rcu() step if the flag is set. fix build error(Shaohua) Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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f5b67ae8 |
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02-Jun-2016 |
NeilBrown <neilb@suse.com> |
md: be extra careful not to take a reference to a Faulty device. It is important that we never increment rdev->nr_pending on a Faulty device as ->hot_remove_disk() assumes that once the Faulty flag is visible no code will take a new reference. Some places take a new reference after only check In_sync. This should be safe as the two are changed together. However to make the code more obviously safe, add checks for 'Faulty' as well. Note: the actual rule is: Never increment nr_pending if Faulty is set and Blocked is clear, never clear Faulty, and never set Blocked without holding a reference through nr_pending. fix build error (Shaohua) Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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5fd13351 |
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02-Jun-2016 |
NeilBrown <neilb@suse.com> |
md/raid5: add rcu protection to rdev accesses in raid5_status. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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3f232d6a |
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02-Jun-2016 |
NeilBrown <neilb@suse.com> |
md/raid5: add rcu protection to rdev accesses in want_replace Being in the middle of resync is no longer protection against failed rdevs disappearing. So add rcu protection. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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e50d3992 |
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02-Jun-2016 |
NeilBrown <neilb@suse.com> |
md/raid5: add rcu protection to rdev accesses in handle_failed_sync. The rdev could be freed while handle_failed_sync is running, so rcu protection is needed. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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28a8f0d3 |
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05-Jun-2016 |
Mike Christie <mchristi@redhat.com> |
block, drivers, fs: rename REQ_FLUSH to REQ_PREFLUSH To avoid confusion between REQ_OP_FLUSH, which is handled by request_fn drivers, and upper layers requesting the block layer perform a flush sequence along with possibly a WRITE, this patch renames REQ_FLUSH to REQ_PREFLUSH. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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6296b960 |
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05-Jun-2016 |
Mike Christie <mchristi@redhat.com> |
block, drivers, fs: shrink bi_rw from long to int We don't need bi_rw to be so large on 64 bit archs, so reduce it to unsigned int. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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796a5cf0 |
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05-Jun-2016 |
Mike Christie <mchristi@redhat.com> |
md: use bio op accessors Separate the op from the rq_flag_bits and have md set/get the bio using bio_set_op_attrs/bio_op. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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41257580 |
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23-May-2016 |
Song Liu <songliubraving@fb.com> |
right meaning of PARITY_ENABLE_RMW and PARITY_PREFER_RMW In current handle_stripe_dirtying, the code prefers rmw with PARITY_ENABLE_RMW; while prefers rcw with PARITY_PREFER_RMW. This patch reverses this behavior. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
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85ad1d13 |
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03-May-2016 |
Guoqing Jiang <gqjiang@suse.com> |
md: set MD_CHANGE_PENDING in a atomic region Some code waits for a metadata update by: 1. flagging that it is needed (MD_CHANGE_DEVS or MD_CHANGE_CLEAN) 2. setting MD_CHANGE_PENDING and waking the management thread 3. waiting for MD_CHANGE_PENDING to be cleared If the first two are done without locking, the code in md_update_sb() which checks if it needs to repeat might test if an update is needed before step 1, then clear MD_CHANGE_PENDING after step 2, resulting in the wait returning early. So make sure all places that set MD_CHANGE_PENDING are atomicial, and bit_clear_unless (suggested by Neil) is introduced for the purpose. Cc: Martin Kepplinger <martink@posteo.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: <linux-kernel@vger.kernel.org> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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fe67d19a |
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03-May-2016 |
Heinz Mauelshagen <heinzm@redhat.com> |
md: raid5: add prerequisite to run underneath dm-raid In case md runs underneath the dm-raid target, the mddev does not have a request queue or gendisk, thus avoid accesses. This patch adds a missing conditional to the raid5 personality. Signed-of-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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b8a0b8e9 |
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29-Apr-2016 |
Shaohua Li <shli@fb.com> |
raid5: delete unnecessary warnning If device has R5_LOCKED set, it's legit device has R5_SkipCopy set and page != orig_page. After R5_LOCKED is clear, handle_stripe_clean_event will clear the SkipCopy flag and set page to orig_page. So the warning is unnecessary. Reported-by: Joey Liao <joeyliao@qnap.com> Signed-off-by: Shaohua Li <shli@fb.com>
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1d034e68 |
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16-Mar-2016 |
Anna-Maria Gleixner <anna-maria@linutronix.de> |
md/raid5: Cleanup cpu hotplug notifier The raid456_cpu_notify() hotplug callback lacks handling of the CPU_UP_CANCELED case. That means if CPU_UP_PREPARE fails, the scratch buffer is leaked. Add handling for CPU_UP_CANCELED[_FROZEN] hotplug notifier transitions to free the scratch buffer. CC: Shaohua Li <shli@kernel.org> CC: linux-raid@vger.kernel.org Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Shaohua Li <shli@fb.com>
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fb3229d5 |
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09-Mar-2016 |
Shaohua Li <shli@fb.com> |
md/raid5: output stripe state for debug Neil recently fixed an obscure race in break_stripe_batch_list. Debug would be quite convenient if we know the stripe state. This is what this patch does. Signed-off-by: Shaohua Li <shli@fb.com>
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550da24f |
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08-Mar-2016 |
NeilBrown <neilb@suse.com> |
md/raid5: preserve STRIPE_PREREAD_ACTIVE in break_stripe_batch_list break_stripe_batch_list breaks up a batch and copies some flags from the batch head to the members, preserving others. It doesn't preserve or copy STRIPE_PREREAD_ACTIVE. This is not normally a problem as STRIPE_PREREAD_ACTIVE is cleared when a stripe_head is added to a batch, and is not set on stripe_heads already in a batch. However there is no locking to ensure one thread doesn't set the flag after it has just been cleared in another. This does occasionally happen. md/raid5 maintains a count of the number of stripe_heads with STRIPE_PREREAD_ACTIVE set: conf->preread_active_stripes. When break_stripe_batch_list clears STRIPE_PREREAD_ACTIVE inadvertently this could becomes incorrect and will never again return to zero. md/raid5 delays the handling of some stripe_heads until preread_active_stripes becomes zero. So when the above mention race happens, those stripe_heads become blocked and never progress, resulting is write to the array handing. So: change break_stripe_batch_list to preserve STRIPE_PREREAD_ACTIVE in the members of a batch. URL: https://bugzilla.kernel.org/show_bug.cgi?id=108741 URL: https://bugzilla.redhat.com/show_bug.cgi?id=1258153 URL: http://thread.gmane.org/5649C0E9.2030204@zoner.cz Reported-by: Martin Svec <martin.svec@zoner.cz> (and others) Tested-by: Tom Weber <linux@junkyard.4t2.com> Fixes: 1b956f7a8f9a ("md/raid5: be more selective about distributing flags across batch.") Cc: stable@vger.kernel.org (v4.1 and later) Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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6ab2a4b8 |
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25-Feb-2016 |
Shaohua Li <shli@fb.com> |
RAID5: revert e9e4c377e2f563 to fix a livelock Revert commit e9e4c377e2f563(md/raid5: per hash value and exclusive wait_for_stripe) The problem is raid5_get_active_stripe waits on conf->wait_for_stripe[hash]. Assume hash is 0. My test release stripes in this order: - release all stripes with hash 0 - raid5_get_active_stripe still sleeps since active_stripes > max_nr_stripes * 3 / 4 - release all stripes with hash other than 0. active_stripes becomes 0 - raid5_get_active_stripe still sleeps, since nobody wakes up wait_for_stripe[0] The system live locks. The problem is active_stripes isn't a per-hash count. Revert the patch makes the live lock go away. Cc: stable@vger.kernel.org (v4.2+) Cc: Yuanhan Liu <yuanhan.liu@linux.intel.com> Cc: NeilBrown <neilb@suse.de> Signed-off-by: Shaohua Li <shli@fb.com>
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27a353c0 |
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24-Feb-2016 |
Shaohua Li <shli@fb.com> |
RAID5: check_reshape() shouldn't call mddev_suspend check_reshape() is called from raid5d thread. raid5d thread shouldn't call mddev_suspend(), because mddev_suspend() waits for all IO finish but IO is handled in raid5d thread, we could easily deadlock here. This issue is introduced by 738a273 ("md/raid5: fix allocation of 'scribble' array.") Cc: stable@vger.kernel.org (v4.1+) Reported-and-tested-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
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e7597e69 |
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16-Feb-2016 |
Jes Sorensen <Jes.Sorensen@redhat.com> |
md/raid5: Compare apples to apples (or sectors to sectors) 'max_discard_sectors' is in sectors, while 'stripe' is in bytes. This fixes the problem where DISCARD would get disabled on some larger RAID5 configurations (6 or more drives in my testing), while it worked as expected with smaller configurations. Fixes: 620125f2bf8 ("MD: raid5 trim support") Cc: stable@vger.kernel.org v3.7+ Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
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849674e4 |
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20-Jan-2016 |
Shaohua Li <shli@fb.com> |
MD: rename some functions These short function names are hard to search. Rename them to make vim happy. Signed-off-by: Shaohua Li <shli@fb.com>
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f6b6ec5c |
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20-Dec-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: add journal hot add/remove support Add support for journal disk hot add/remove. Mostly trival checks in md part. The raid5 part is a little tricky. For hot-remove, we can't wait pending write as it's called from raid5d. The wait will cause deadlock. We simplily fail the hot-remove. A hot-remove retry can success eventually since if journal disk is faulty all pending write will be failed and finish. For hot-add, since an array supporting journal but without journal disk will be marked read-only, we are safe to hot add journal without stopping IO (should be read IO, while journal only handles write IO). Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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b46020aa |
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20-Dec-2015 |
Roman Gushchin <klamm@yandex-team.ru> |
md/raid5: remove redundant check in stripe_add_to_batch_list() The stripe_add_to_batch_list() function is called only if stripe_can_batch() returned true, so there is no need for double check. Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Cc: Neil Brown <neilb@suse.com> Cc: linux-raid@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.com>
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f2076e7d |
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08-Oct-2015 |
Shaohua Li <shli@fb.com> |
MD: set journal disk ->raid_disk Set journal disk ->raid_disk to >=0, I choose raid_disks + 1 instead of 0, because we already have a disk with ->raid_disk 0 and this causes sysfs entry creation conflict. A lot of places assumes disk with ->raid_disk >=0 is normal raid disk, so we add check for journal disk. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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7dde2ad3 |
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08-Oct-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: start raid5 readonly if journal is missing If raid array is expected to have journal (eg, journal is set in MD superblock feature map) and the array is started without journal disk, start the array readonly. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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6e74a9cf |
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08-Oct-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: IO error handling There are 3 places the raid5-cache dispatches IO. The discard IO error doesn't matter, so we ignore it. The superblock write IO error can be handled in MD core. The remaining are log write and flush. When the IO error happens, we mark log disk faulty and fail all write IO. Read IO is still allowed to run. Userspace will get a notification too and corresponding daemon can choose setting raid array readonly for example. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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c2bb6242 |
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08-Oct-2015 |
Shaohua Li <shli@fb.com> |
raid5: journal disk can't be removed raid5-cache uses journal disk rdev->bdev, rdev->mddev in several places. Don't allow journal disk disappear magically. On the other hand, we do need to update superblock for other disks to bump up ->events, so next time journal disk will be identified as stale. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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e6c033f7 |
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04-Oct-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: move reclaim stop to quiesce Move reclaim stop to quiesce handling, where is safer for this stuff. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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828cbe98 |
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02-Sep-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: optimize FLUSH IO with log enabled With log enabled, bio is written to raid disks after the bio is settled down in log disk. The recovery guarantees we can recovery the bio data from log disk, so we we skip FLUSH IO. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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a8c34f91 |
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02-Sep-2015 |
Shaohua Li <shli@fb.com> |
raid5-cache: switching to state machine for log disk cache flush Before we write stripe data to raid disks, we must guarantee stripe data is settled down in log disk. To do this, we flush log disk cache and wait the flush finish. That wait introduces sleep time in raid5d thread and impact performance. This patch moves the log disk cache flush process to the stripe handling state machine, which can remove the wait in raid5d. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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5c7e81c3 |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: enable log for raid array with cache disk Now log is safe to enable for raid array with cache disk Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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713cf5a6 |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: don't allow resize/reshape with cache(log) support If cache(log) support is enabled, don't allow resize/reshape in current stage. In the future, we can flush all data from cache(log) to raid before resize/reshape and then allow resize/reshape. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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9c3e333d |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: disable batch with log enabled With log enabled, r5l_write_stripe will add the stripe to log. With batch, several stripes are linked together. The stripes must be in the same state. While with log, the log/reclaim unit is stripe, we can't guarantee the several stripes are in the same state. Disabling batch for log now. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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b8a9d66d |
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30-Oct-2015 |
Roman Gushchin <klamm@yandex-team.ru> |
md/raid5: fix locking in handle_stripe_clean_event() After commit 566c09c53455 ("raid5: relieve lock contention in get_active_stripe()") __find_stripe() is called under conf->hash_locks + hash. But handle_stripe_clean_event() calls remove_hash() under conf->device_lock. Under some cirscumstances the hash chain can be circuited, and we get an infinite loop with disabled interrupts and locked hash lock in __find_stripe(). This leads to hard lockup on multiple CPUs and following system crash. I was able to reproduce this behavior on raid6 over 6 ssd disks. The devices_handle_discard_safely option should be set to enable trim support. The following script was used: for i in `seq 1 32`; do dd if=/dev/zero of=large$i bs=10M count=100 & done neilb: original was against a 3.x kernel. I forward-ported to 4.3-rc. This verison is suitable for any kernel since Commit: 59fc630b8b5f ("RAID5: batch adjacent full stripe write") (v4.1+). I'll post a version for earlier kernels to stable. Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Fixes: 566c09c53455 ("raid5: relieve lock contention in get_active_stripe()") Signed-off-by: NeilBrown <neilb@suse.com> Cc: Shaohua Li <shli@kernel.org> Cc: <stable@vger.kernel.org> # 3.13 - 4.2
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0576b1c6 |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: log reclaim support This is the reclaim support for raid5 log. A stripe write will have following steps: 1. reconstruct the stripe, read data/calculate parity. ops_run_io prepares to write data/parity to raid disks 2. hijack ops_run_io. stripe data/parity is appending to log disk 3. flush log disk cache 4. ops_run_io run again and do normal operation. stripe data/parity is written in raid array disks. raid core can return io to upper layer. 5. flush cache of all raid array disks 6. update super block 7. log disk space used by the stripe can be reused In practice, several stripes consist of an io_unit and we will batch several io_unit in different steps, but the whole process doesn't change. It's possible io return just after data/parity hit log disk, but then read IO will need read from log disk. For simplicity, IO return happens at step 4, where read IO can directly read from raid disks. Currently reclaim run if there is specific reclaimable space (1/4 disk size or 10G) or we are out of space. Reclaim is just to free log disk spaces, it doesn't impact data consistency. The size based force reclaim is to make sure log isn't too big, so recovery doesn't scan log too much. Recovery make sure raid disks and log disk have the same data of a stripe. If crash happens before 4, recovery might/might not recovery stripe's data/parity depending on if data/parity and its checksum matches. In either case, this doesn't change the syntax of an IO write. After step 3, stripe is guaranteed recoverable, because stripe's data/parity is persistent in log disk. In some cases, log disk content and raid disks content of a stripe are the same, but recovery will still copy log disk content to raid disks, this doesn't impact data consistency. space reuse happens after superblock update and cache flush. There is one situation we want to avoid. A broken meta in the middle of a log causes recovery can't find meta at the head of log. If operations require meta at the head persistent in log, we must make sure meta before it persistent in log too. The case is stripe data/parity is in log and we start write stripe to raid disks (before step 4). stripe data/parity must be persistent in log before we do the write to raid disks. The solution is we restrictly maintain io_unit list order. In this case, we only write stripes of an io_unit to raid disks till the io_unit is the first one whose data/parity is in log. The io_unit list order is important for other cases too. For example, some io_unit are reclaimable and others not. They can be mixed in the list, we shouldn't reuse space of an unreclaimable io_unit. Includes fixes to problems which were... Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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f6bed0ef |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: add basic stripe log This introduces a simple log for raid5. Data/parity writing to raid array first writes to the log, then write to raid array disks. If crash happens, we can recovery data from the log. This can speed up raid resync and fix write hole issue. The log structure is pretty simple. Data/meta data is stored in block unit, which is 4k generally. It has only one type of meta data block. The meta data block can track 3 types of data, stripe data, stripe parity and flush block. MD superblock will point to the last valid meta data block. Each meta data block has checksum/seq number, so recovery can scan the log correctly. We store a checksum of stripe data/parity to the metadata block, so meta data and stripe data/parity can be written to log disk together. otherwise, meta data write must wait till stripe data/parity is finished. For stripe data, meta data block will record stripe data sector and size. Currently the size is always 4k. This meta data record can be made simpler if we just fix write hole (eg, we can record data of a stripe's different disks together), but this format can be extended to support caching in the future, which must record data address/size. For stripe parity, meta data block will record stripe sector. It's size should be 4k (for raid5) or 8k (for raid6). We always store p parity first. This format should work for caching too. flush block indicates a stripe is in raid array disks. Fixing write hole doesn't need this type of meta data, it's for caching extension. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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b70abcb2 |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: add a new state for stripe log handling When a stripe finishes construction, we write the stripe to raid in ops_run_io normally. With log, we do a bunch of other operations before the stripe is written to raid. Mainly write the stripe to log disk, flush disk cache and so on. The operations are still driven by raid5d and run in the stripe state machine. We introduce a new state for such stripe (trapped into log). The stripe is in this state from the time it first enters ops_run_io (finish construction) to the time it is written to raid. Since we know the state is only for log, we bypass other check/operation in handle_stripe. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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6d036f7d |
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13-Aug-2015 |
Shaohua Li <shli@fb.com> |
raid5: export some functions Next several patches use some raid5 functions, rename them with raid5 prefix and export out. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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c40f341f |
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18-Aug-2015 |
Goldwyn Rodrigues <rgoldwyn@suse.com> |
md-cluster: Use a small window for resync Suspending the entire device for resync could take too long. Resync in small chunks. cluster's resync window (32M) is maintained in r1conf as cluster_sync_low and cluster_sync_high and processed in raid1's sync_request(). If the current resync is outside the cluster resync window: 1. Set the cluster_sync_low to curr_resync_completed. 2. Check if the sync will fit in the new window, if not issue a wait_barrier() and set cluster_sync_low to sector_nr. 3. Set cluster_sync_high to cluster_sync_low + resync_window. 4. Send a message to all nodes so they may add it in their suspension list. bitmap_cond_end_sync is modified to allow to force a sync inorder to get the curr_resync_completed uptodate with the sector passed. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
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644df1a8 |
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13-Sep-2015 |
Julia Lawall <Julia.Lawall@lip6.fr> |
md: drop null test before destroy functions Remove unneeded NULL test. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ -if (x != NULL) \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: NeilBrown <neilb@suse.com>
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36707bb2 |
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23-Sep-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: don't index beyond end of array in need_this_block(). When need_this_block probably shouldn't be called when there are more than 2 failed devices, we really don't want it to try indexing beyond the end of the failed_num[] of fdev[] arrays. So limit the loops to at most 2 iterations. Reported-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.de>
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ebda780b |
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18-Sep-2015 |
Shaohua Li <shli@fb.com> |
raid5: update analysis state for failed stripe handle_failed_stripe() makes the stripe fail, eg, all IO will return with a failure, but it doesn't update stripe_head_state. Later handle_stripe() has special handling for raid6 for handle_stripe_fill(). That check before handle_stripe_fill() doesn't skip the failed stripe and we get a kernel crash in need_this_block. This patch clear the analysis state to make sure no functions wrongly called after handle_failed_stripe() Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.com>
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c3cce6cd |
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13-Aug-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: ensure device failure recorded before write request returns. When a write to one of the devices of a RAID5/6 fails, the failure is recorded in the metadata of the other devices so that after a restart the data on the failed drive wont be trusted even if that drive seems to be working again (maybe a cable was unplugged). Similarly when we record a bad-block in response to a write failure, we must not let the write complete until the bad-block update is safe. Currently there is no interlock between the write request completing and the metadata update. So it is possible that the write will complete, the app will confirm success in some way, and then the machine will crash before the metadata update completes. This is an extremely small hole for a racy to fit in, but it is theoretically possible and so should be closed. So: - set MD_CHANGE_PENDING when requesting a metadata update for a failed device, so we can know with certainty when it completes - queue requests that completed when MD_CHANGE_PENDING is set to only be processed after the metadata update completes - call raid_end_bio_io() on bios in that queue when the time comes. Signed-off-by: NeilBrown <neilb@suse.com>
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34a6f80e |
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13-Aug-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: use bio_list for the list of bios to return. This will make it easier to splice two lists together which will be needed in future patch. Signed-off-by: NeilBrown <neilb@suse.com>
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6cbd8148 |
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23-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: handle possible race as reshape completes. It is possible (though unlikely) for a reshape to be interrupted between the time that end_reshape is called and the time when raid5_finish_reshape is called. This can leave conf->reshape_progress set to MaxSector, but mddev->reshape_position not. This combination confused reshape_request() when ->reshape_backwards. As conf->reshape_progress is so high, it seems the reshape hasn't really begun. But assuming MaxSector is a valid address only leads to sorrow. So ensure reshape_position and reshape_progress both agree, and add an extra check in reshape_request() just in case they don't. Signed-off-by: NeilBrown <neilb@suse.com>
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c5e19d90 |
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16-Jul-2015 |
NeilBrown <neilb@suse.com> |
md: be careful when testing resync_max against curr_resync_completed. While it generally shouldn't happen, it is not impossible for curr_resync_completed to exceed resync_max. This can particularly happen when reshaping RAID5 - the current status isn't copied to curr_resync_completed promptly, so when it is, it can exceed resync_max. This happens when the reshape is 'frozen', resync_max is set low, and reshape is re-enabled. Taking a difference between two unsigned numbers is always dangerous anyway, so add a test to behave correctly if curr_resync_completed > resync_max Signed-off-by: NeilBrown <neilb@suse.com>
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c74c0d76 |
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15-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: remove incorrect "min_t()" when calculating writepos. This code is calculating: writepos, which is the furthest along address (device-space) that we *will* be writing to readpos, which is the earliest address that we *could* possible read from, and safepos, which is the earliest address in the 'old' section that we might read from after a crash when the reshape position is recovered from metadata. The first is a precise calculation, so clipping at zero doesn't make sense. As the reshape position is now guaranteed to always be a multiple of reshape_sectors and as we already BUG_ON when reshape_progress is zero, there is no point in this min_t() call. The readpos and safepos are worst case - actual value depends on precise geometry. That worst case could be negative, which is only a problem because we are storing the value in an unsigned. So leave the min_t() for those. Signed-off-by: NeilBrown <neilb@suse.com>
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05256d98 |
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15-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: strengthen check on reshape_position at run. When reshaping, we work in units of the largest chunk size. If changing from a larger to a smaller chunk size, that means we reshape more than one stripe at a time. So the required alignment of reshape_position needs to take into account both the old and new chunk size. This means that both 'here_new' and 'here_old' are calculated with respect to the same (maximum) chunk size, so testing if they are the same when delta_disks is zero becomes pointless. Signed-off-by: NeilBrown <neilb@suse.com>
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3cb5edf4 |
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15-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: switch to use conf->chunk_sectors in place of mddev->chunk_sectors where possible The chunk_sectors and new_chunk_sectors fields of mddev can be changed any time (via sysfs) that the reconfig mutex can be taken. So raid5 keeps internal copies in 'conf' which are stable except for a short locked moment when reshape stops/starts. So any access that does not hold reconfig_mutex should use the 'conf' values, not the 'mddev' values. Several don't. This could result in corruption if new values were written at awkward times. Also use min() or max() rather than open-coding. Signed-off-by: NeilBrown <neilb@suse.com>
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5cac6bcb |
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16-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: always set conf->prev_chunk_sectors and ->prev_algo These aren't really needed when no reshape is happening, but it is safer to have them always set to a meaningful value. The next patch will use ->prev_chunk_sectors without checking if a reshape is happening (because that makes the code simpler), and this patch makes that safe. Signed-off-by: NeilBrown <neilb@suse.com>
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92140480 |
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05-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: consider updating reshape_position at start of reshape. md/raid5 only updates ->reshape_position (which is stored in metadata and is authoritative) occasionally, but particularly when getting closed to ->resync_max as it must be correct when ->resync_max is reached. When mdadm tries to stop an array which is reshaping it will: - freeze the reshape, - set resync_max to where the reshape has reached. - unfreeze the reshape. When this happens, the reshape is aborted and then restarted. The restart doesn't check that resync_max is close, and so doesn't update ->reshape_position like it should. This results in the reshape stopping, but ->reshape_position being incorrect. So on that first call to reshape_request, make sure ->reshape_position is updated if needed. Signed-off-by: NeilBrown <neilb@suse.com>
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8ae12666 |
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28-Apr-2015 |
Kent Overstreet <kent.overstreet@gmail.com> |
block: kill merge_bvec_fn() completely As generic_make_request() is now able to handle arbitrarily sized bios, it's no longer necessary for each individual block driver to define its own ->merge_bvec_fn() callback. Remove every invocation completely. Cc: Jens Axboe <axboe@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: drbd-user@lists.linbit.com Cc: Jiri Kosina <jkosina@suse.cz> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@kernel.org> Cc: ceph-devel@vger.kernel.org Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Acked-by: NeilBrown <neilb@suse.de> (for the 'md' bits) Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: also remove ->merge_bvec_fn() in dm-thin as well as dm-era-target, and resolve merge conflicts] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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7140aafc |
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25-Sep-2013 |
Kent Overstreet <kent.overstreet@gmail.com> |
md/raid5: get rid of bio_fits_rdev() Remove bio_fits_rdev() as sufficient merge_bvec_fn() handling is now performed by blk_queue_split() in md_make_request(). Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: add more description in commit message] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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7ef6b12a |
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06-May-2015 |
Ming Lin <ming.l@ssi.samsung.com> |
md/raid5: split bio for chunk_aligned_read If a read request fits entirely in a chunk, it will be passed directly to the underlying device (providing it hasn't failed of course). If it doesn't fit, the slightly less efficient path that uses the stripe_cache is used. Requests that get to the stripe cache are always completely split up as necessary. So with RAID5, ripping out the merge_bvec_fn doesn't cause it to stop work, but could cause it to take the less efficient path more often. All that is needed to manage this is for 'chunk_aligned_read' do some bio splitting, much like the RAID0 code does. Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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9b81c842 |
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10-Aug-2015 |
Sasha Levin <sasha.levin@oracle.com> |
block: don't access bio->bi_error after bio_put() Commit 4246a0b6 ("block: add a bi_error field to struct bio") has added a few dereferences of 'bio' after a call to bio_put(). This causes use-after-frees such as: [521120.719695] BUG: KASan: use after free in dio_bio_complete+0x2b3/0x320 at addr ffff880f36b38714 [521120.720638] Read of size 4 by task mount.ocfs2/9644 [521120.721212] ============================================================================= [521120.722056] BUG kmalloc-256 (Not tainted): kasan: bad access detected [521120.722968] ----------------------------------------------------------------------------- [521120.722968] [521120.723915] Disabling lock debugging due to kernel taint [521120.724539] INFO: Slab 0xffffea003cdace00 objects=32 used=25 fp=0xffff880f36b38600 flags=0x46fffff80004080 [521120.726037] INFO: Object 0xffff880f36b38700 @offset=1792 fp=0xffff880f36b38800 [521120.726037] [521120.726974] Bytes b4 ffff880f36b386f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.727898] Object ffff880f36b38700: 00 88 b3 36 0f 88 ff ff 00 00 d8 de 0b 88 ff ff ...6............ [521120.728822] Object ffff880f36b38710: 02 00 00 f0 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.729705] Object ffff880f36b38720: 01 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 ................ [521120.730623] Object ffff880f36b38730: 00 00 00 00 00 00 00 00 01 00 00 00 00 02 00 00 ................ [521120.731621] Object ffff880f36b38740: 00 02 00 00 01 00 00 00 d0 f7 87 ad ff ff ff ff ................ [521120.732776] Object ffff880f36b38750: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.733640] Object ffff880f36b38760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.734508] Object ffff880f36b38770: 01 00 03 00 01 00 00 00 88 87 b3 36 0f 88 ff ff ...........6.... [521120.735385] Object ffff880f36b38780: 00 73 22 ad 02 88 ff ff 40 13 e0 3c 00 ea ff ff .s".....@..<.... [521120.736667] Object ffff880f36b38790: 00 02 00 00 00 04 00 00 00 00 00 00 00 00 00 00 ................ [521120.737596] Object ffff880f36b387a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.738524] Object ffff880f36b387b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.739388] Object ffff880f36b387c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.740277] Object ffff880f36b387d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.741187] Object ffff880f36b387e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.742233] Object ffff880f36b387f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.743229] CPU: 41 PID: 9644 Comm: mount.ocfs2 Tainted: G B 4.2.0-rc6-next-20150810-sasha-00039-gf909086 #2420 [521120.744274] ffff880f36b38000 ffff880d89c8f638 ffffffffb6e9ba8a ffff880101c0e5c0 [521120.745025] ffff880d89c8f668 ffffffffad76a313 ffff880101c0e5c0 ffffea003cdace00 [521120.745908] ffff880f36b38700 ffff880f36b38798 ffff880d89c8f690 ffffffffad772854 [521120.747063] Call Trace: [521120.747520] dump_stack (lib/dump_stack.c:52) [521120.748053] print_trailer (mm/slub.c:653) [521120.748582] object_err (mm/slub.c:660) [521120.749079] kasan_report_error (include/linux/kasan.h:20 mm/kasan/report.c:152 mm/kasan/report.c:194) [521120.750834] __asan_report_load4_noabort (mm/kasan/report.c:250) [521120.753580] dio_bio_complete (fs/direct-io.c:478) [521120.755752] do_blockdev_direct_IO (fs/direct-io.c:494 fs/direct-io.c:1291) [521120.759765] __blockdev_direct_IO (fs/direct-io.c:1322) [521120.761658] blkdev_direct_IO (fs/block_dev.c:162) [521120.762993] generic_file_read_iter (mm/filemap.c:1738) [521120.767405] blkdev_read_iter (fs/block_dev.c:1649) [521120.768556] __vfs_read (fs/read_write.c:423 fs/read_write.c:434) [521120.772126] vfs_read (fs/read_write.c:454) [521120.773118] SyS_pread64 (fs/read_write.c:607 fs/read_write.c:594) [521120.776062] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:186) [521120.777375] Memory state around the buggy address: [521120.778118] ffff880f36b38600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.779211] ffff880f36b38680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.780315] >ffff880f36b38700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.781465] ^ [521120.782083] ffff880f36b38780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.783717] ffff880f36b38800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [521120.784818] ================================================================== This patch fixes a few of those places that I caught while auditing the patch, but the original patch should be audited further for more occurences of this issue since I'm not too familiar with the code. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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49895bcc |
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03-Aug-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: don't let shrink_slab shrink too far. I have a report of drop_one_stripe() called from raid5_cache_scan() apparently finding ->max_nr_stripes == 0. This should not be allowed. So add a test to keep max_nr_stripes above min_nr_stripes. Also use a 'mask' rather than a 'mod' in drop_one_stripe to ensure 'hash' is valid even if max_nr_stripes does reach zero. Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org (4.1 - please release with 2d5b569b665) Reported-by: Tomas Papan <tomas.papan@gmail.com> Signed-off-by: NeilBrown <neilb@suse.com>
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#
b7c44ed9 |
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24-Jul-2015 |
Jens Axboe <axboe@fb.com> |
block: manipulate bio->bi_flags through helpers Some places use helpers now, others don't. We only have the 'is set' helper, add helpers for setting and clearing flags too. It was a bit of a mess of atomic vs non-atomic access. With BIO_UPTODATE gone, we don't have any risk of concurrent access to the flags. So relax the restriction and don't make any of them atomic. The flags that do have serialization issues (reffed and chained), we already handle those separately. Signed-off-by: Jens Axboe <axboe@fb.com>
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4246a0b6 |
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20-Jul-2015 |
Christoph Hellwig <hch@lst.de> |
block: add a bi_error field to struct bio Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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#
e6030cb0 |
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16-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: clear R5_NeedReplace when no longer needed. This flag is currently never cleared, which can in rare cases trigger a warn-on if it is still set but the block isn't InSync. So clear it when it isn't need, which includes if the replacement device has failed. Signed-off-by: NeilBrown <neilb@suse.com>
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#
2d5b569b |
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05-Jul-2015 |
NeilBrown <neilb@suse.com> |
md/raid5: avoid races when changing cache size. Cache size can grow or shrink due to various pressures at any time. So when we resize the cache as part of a 'grow' operation (i.e. change the size to allow more devices) we need to blocks that automatic growing/shrinking. So introduce a mutex. auto grow/shrink uses mutex_trylock() and just doesn't bother if there is a blockage. Resizing the whole cache holds the mutex to ensure that the correct number of new stripes is allocated. This bug can result in some stripes not being freed when an array is stopped. This leads to the kmem_cache not being freed and a subsequent array can try to use the same kmem_cache and get confused. Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org (4.1 - please delay until 2 weeks after release of 4.2) Signed-off-by: NeilBrown <neilb@suse.com>
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#
713bc5c2 |
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28-May-2015 |
Shaohua Li <shli@fb.com> |
md/raid5: ignore released_stripes check conf->released_stripes list isn't always related to where there are free stripes pending. Active stripes can be in the list too. And even free stripes were active very recently. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
e9e4c377 |
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08-May-2015 |
Yuanhan Liu <yuanhan.liu@linux.intel.com> |
md/raid5: per hash value and exclusive wait_for_stripe I noticed heavy spin lock contention at get_active_stripe() with fsmark multiple thread write workloads. Here is how this hot contention comes from. We have limited stripes, and it's a multiple thread write workload. Hence, those stripes will be taken soon, which puts later processes to sleep for waiting free stripes. When enough stripes(>= 1/4 total stripes) are released, all process are woken, trying to get the lock. But there is one only being able to get this lock for each hash lock, making other processes spinning out there for acquiring the lock. Thus, it's effectiveless to wakeup all processes and let them battle for a lock that permits one to access only each time. Instead, we could make it be a exclusive wake up: wake up one process only. That avoids the heavy spin lock contention naturally. To do the exclusive wake up, we've to split wait_for_stripe into multiple wait queues, to make it per hash value, just like the hash lock. Here are some test results I have got with this patch applied(all test run 3 times): `fsmark.files_per_sec' ===================== next-20150317 this patch ------------------------- ------------------------- metric_value ±stddev metric_value ±stddev change testbox/benchmark/testcase-params ------------------------- ------------------------- -------- ------------------------------ 25.600 ±0.0 92.700 ±2.5 262.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-btrfs-4M-30G-fsyncBeforeClose 25.600 ±0.0 77.800 ±0.6 203.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-btrfs-4M-30G-fsyncBeforeClose 32.000 ±0.0 93.800 ±1.7 193.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-ext4-4M-30G-fsyncBeforeClose 32.000 ±0.0 81.233 ±1.7 153.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-ext4-4M-30G-fsyncBeforeClose 48.800 ±14.5 99.667 ±2.0 104.2% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-xfs-4M-30G-fsyncBeforeClose 6.400 ±0.0 12.800 ±0.0 100.0% ivb44/fsmark/1x-64t-3HDD-RAID5-btrfs-4M-40G-fsyncBeforeClose 63.133 ±8.2 82.800 ±0.7 31.2% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-xfs-4M-30G-fsyncBeforeClose 245.067 ±0.7 306.567 ±7.9 25.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-f2fs-4M-30G-fsyncBeforeClose 17.533 ±0.3 21.000 ±0.8 19.8% ivb44/fsmark/1x-1t-3HDD-RAID5-xfs-4M-40G-fsyncBeforeClose 188.167 ±1.9 215.033 ±3.1 14.3% ivb44/fsmark/1x-1t-4BRD_12G-RAID5-btrfs-4M-30G-NoSync 254.500 ±1.8 290.733 ±2.4 14.2% ivb44/fsmark/1x-1t-9BRD_6G-RAID5-btrfs-4M-30G-NoSync `time.system_time' ===================== next-20150317 this patch ------------------------- ------------------------- metric_value ±stddev metric_value ±stddev change testbox/benchmark/testcase-params ------------------------- ------------------------- -------- ------------------------------ 7235.603 ±1.2 185.163 ±1.9 -97.4% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-btrfs-4M-30G-fsyncBeforeClose 7666.883 ±2.9 202.750 ±1.0 -97.4% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-btrfs-4M-30G-fsyncBeforeClose 14567.893 ±0.7 421.230 ±0.4 -97.1% ivb44/fsmark/1x-64t-3HDD-RAID5-btrfs-4M-40G-fsyncBeforeClose 3697.667 ±14.0 148.190 ±1.7 -96.0% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-xfs-4M-30G-fsyncBeforeClose 5572.867 ±3.8 310.717 ±1.4 -94.4% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-ext4-4M-30G-fsyncBeforeClose 5565.050 ±0.5 313.277 ±1.5 -94.4% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-ext4-4M-30G-fsyncBeforeClose 2420.707 ±17.1 171.043 ±2.7 -92.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-xfs-4M-30G-fsyncBeforeClose 3743.300 ±4.6 379.827 ±3.5 -89.9% ivb44/fsmark/1x-64t-3HDD-RAID5-ext4-4M-40G-fsyncBeforeClose 3308.687 ±6.3 363.050 ±2.0 -89.0% ivb44/fsmark/1x-64t-3HDD-RAID5-xfs-4M-40G-fsyncBeforeClose Where, 1x: where 'x' means iterations or loop, corresponding to the 'L' option of fsmark 1t, 64t: where 't' means thread 4M: means the single file size, corresponding to the '-s' option of fsmark 40G, 30G, 120G: means the total test size 4BRD_12G: BRD is the ramdisk, where '4' means 4 ramdisk, and where '12G' means the size of one ramdisk. So, it would be 48G in total. And we made a raid on those ramdisk As you can see, though there are no much performance gain for hard disk workload, the system time is dropped heavily, up to 97%. And as expected, the performance increased a lot, up to 260%, for fast device(ram disk). v2: use bits instead of array to note down wait queue need to wake up. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b1b46486 |
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08-May-2015 |
Yuanhan Liu <yuanhan.liu@linux.intel.com> |
md/raid5: split wait_for_stripe and introduce wait_for_quiescent I noticed heavy spin lock contention at get_active_stripe(), introduced at being wake up stage, where a bunch of processes try to re-hold the spin lock again. After giving some thoughts on this issue, I found the lock could be relieved(and even avoided) if we turn the wait_for_stripe to per waitqueue for each lock hash and make the wake up exclusive: wake up one process each time, which avoids the lock contention naturally. Before go hacking with wait_for_stripe, I found it actually has 2 usages: for the array to enter or leave the quiescent state, and also to wait for an available stripe in each of the hash lists. So this patch splits the first usage off into a separate wait_queue, wait_for_quiescent, and the next patch will turn the second usage into one waitqueue for each hash value, and make it exclusive, to relieve the lock contention. v2: wake_up(wait_for_quiescent) when (active_stripes == 0) Commit log refactor suggestion from Neil. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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ea358cd0 |
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12-Jun-2015 |
NeilBrown <neilb@suse.de> |
md: make sure MD_RECOVERY_DONE is clear before starting recovery/resync MD_RECOVERY_DONE is normally cleared by md_check_recovery after a resync etc finished. However it is possible for raid5_start_reshape to race and start a reshape before MD_RECOVERY_DONE is cleared. This can lean to multiple reshapes running at the same time, which isn't good. To make sure it is cleared before starting a reshape, and also clear it when reaping a thread, just to be safe. Signed-off-by: NeilBrown <neilb@suse.de>
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626f2092 |
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21-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: break stripe-batches when the array has failed. Once the array has too much failure, we need to break stripe-batches up so they can all be dealt with. Signed-off-by: NeilBrown <neilb@suse.de>
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787b76fa |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: call break_stripe_batch_list from handle_stripe_clean_event Now that the code in break_stripe_batch_list() is nearly identical to the end of handle_stripe_clean_event, replace the later with a function call. The only remaining difference of any interest is the masking that is applieds to dev[i].flags copied from head_sh. R5_WriteError certainly isn't wanted as it is set per-stripe, not per-patch. R5_Overlap isn't wanted as it is explicitly handled. Signed-off-by: NeilBrown <neilb@suse.de>
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1b956f7a |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: be more selective about distributing flags across batch. When a batch of stripes is broken up, we keep some of the flags that were per-stripe, and copy other flags from the head to all others. This only happens while a stripe is being handled, so many of the flags are irrelevant. The "SYNC_FLAGS" (which I've renamed to make it clear there are several) and STRIPE_DEGRADED are set per-stripe and so need to be preserved. STRIPE_INSYNC is the only flag that is set on the head that needs to be propagated to all others. For safety, add a WARN_ON if others are set, except: STRIPE_HANDLE - this is safe and per-stripe and we are going to set in several cases anyway STRIPE_INSYNC STRIPE_IO_STARTED - this is just a hint and doesn't hurt. STRIPE_ON_PLUG_LIST STRIPE_ON_RELEASE_LIST - It is a point pointless for a batched stripe to be on one of these lists, but it can happen as can be safely ignored. Signed-off-by: NeilBrown <neilb@suse.de>
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3960ce79 |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: add handle_flags arg to break_stripe_batch_list. When we break a stripe_batch_list we sometimes want to set STRIPE_HANDLE on the individual stripes, and sometimes not. So pass a 'handle_flags' arg. If it is zero, always set STRIPE_HANDLE (on non-head stripes). If not zero, only set it if any of the given flags are present. Signed-off-by: NeilBrown <neilb@suse.de>
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fb642b92 |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: duplicate some more handle_stripe_clean_event code in break_stripe_batch_list break_stripe_batch list didn't clear head_sh->batch_head. This was probably a bug. Also clear all R5_Overlap flags and if any were cleared, wake up 'wait_for_overlap'. This isn't always necessary but the worst effect is a little extra checking for code that is waiting on wait_for_overlap. Also, don't use wake_up_nr() because that does the wrong thing if 'nr' is zero, and it number of flags cleared doesn't strongly correlate with the number of threads to wake. Signed-off-by: NeilBrown <neilb@suse.de>
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4e3d62ff |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: remove condition test from check_break_stripe_batch_list. handle_stripe_clean_event() contains a chunk of code very similar to check_break_stripe_batch_list(). If we make the latter more like the former, we can end up with just one copy of this code. This first step removed the condition (and the 'check_') part of the name. This has the added advantage of making it clear what check is being performed at the point where the function is called. Signed-off-by: NeilBrown <neilb@suse.de>
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b15a9dbd |
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21-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: Ensure a batch member is not handled prematurely. If a stripe is a member of a batch, but not the head, it must not be handled separately from the rest of the batch. 'clear_batch_ready()' handles this requirement to some extent but not completely. If a member is passed to handle_stripe() a second time it returns '0' indicating the stripe can be handled, which is wrong. So add an extra test. Signed-off-by: NeilBrown <neilb@suse.de>
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d0852df5 |
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26-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: close race between STRIPE_BIT_DELAY and batching. When we add a write to a stripe we need to make sure the bitmap bit is set. While doing that the stripe is not locked so it could be added to a batch after which further changes to STRIPE_BIT_DELAY and ->bm_seq are ineffective. So we need to hold off adding to a stripe until bitmap_startwrite has completed at least once, and we need to avoid further changes to STRIPE_BIT_DELAY once the stripe has been added to a batch. If a bitmap_startwrite() completes after the stripe was added to a batch, it will not have set the bit, only incremented a counter, so no extra delay of the stripe is needed. Reported-by: Shaohua Li <shli@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de>
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2b6b2457 |
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20-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: ensure whole batch is delayed for all required bitmap updates. When we add a stripe to a batch, we need to be sure that head stripe will wait for the bitmap update required for the new stripe. Signed-off-by: NeilBrown <neilb@suse.de>
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48769695 |
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13-May-2015 |
Shaohua Li <shli@kernel.org> |
raid5: fix broken async operation chain ops_run_reconstruct6() doesn't correctly chain asyn operations. The tx returned by async_gen_syndrome should be added as the dependent tx of next stripe. The issue is introduced by commit 59fc630b8b5f9f21c8ce3ba153341c107dce1b0c RAID5: batch adjacent full stripe write Reported-and-tested-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.de>
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bb27051f |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: fix handling of degraded stripes in batches. There is no need for special handling of stripe-batches when the array is degraded. There may be if there is a failure in the batch, but STRIPE_DEGRADED does not imply an error. So don't set STRIPE_BATCH_ERR in ops_run_io just because the array is degraded. This actually causes a bug: the STRIPE_DEGRADED flag gets cleared in check_break_stripe_batch_list() and so the bitmap bit gets cleared when it shouldn't. So in check_break_stripe_batch_list(), split the batch up completely - again STRIPE_DEGRADED isn't meaningful. Also don't set STRIPE_BATCH_ERR when there is a write error to a replacement device. This simply removes the replacement device and requires no extra handling. Signed-off-by: NeilBrown <neilb@suse.de>
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738a2738 |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: fix allocation of 'scribble' array. As the new 'scribble' array is sized based on chunk size, we need to make sure the size matches the largest of 'old' and 'new' chunk sizes when the array is undergoing reshape. We also potentially need to resize it even when not resizing the stripe cache, as chunk size can change without changing number of devices. So move the 'resize' code into a separate function, and consider old and new sizes when allocating. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: 46d5b785621a ("raid5: use flex_array for scribble data")
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6e9eac2d |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: don't record new size if resize_stripes fails. If any memory allocation in resize_stripes fails we will return -ENOMEM, but in some cases we update conf->pool_size anyway. This means that if we try again, the allocations will be assumed to be larger than they are, and badness results. So only update pool_size if there is no error. This bug was introduced in 2.6.17 and the patch is suitable for -stable. Fixes: ad01c9e3752f ("[PATCH] md: Allow stripes to be expanded in preparation for expanding an array") Cc: stable@vger.kernel.org (v2.6.17+) Signed-off-by: NeilBrown <neilb@suse.de>
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10d82c5f |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: avoid reading parity blocks for full-stripe write to degraded array When performing a reconstruct write, we need to read all blocks that are not being over-written .. except the parity (P and Q) blocks. The code currently reads these (as they are not being over-written!) unnecessarily. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: ea664c8245f3 ("md/raid5: need_this_block: tidy/fix last condition.")
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b0c783b3 |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: more incorrect BUG_ON in handle_stripe_fill. It is not incorrect to call handle_stripe_fill() when a batch of full-stripe writes is active. It is, however, a BUG if fetch_block() then decides it needs to actually fetch anything. So move the 'BUG_ON' to where it belongs. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: 59fc630b8b5f ("RAID5: batch adjacent full stripe write")
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f18c1a35 |
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08-May-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: new alloc_stripe() to allocate an initialize a stripe. The new batch_lock and batch_list fields are being initialized in grow_one_stripe() but not in resize_stripes(). This causes a crash on resize. So separate the core initialization into a new function and call it from both allocation sites. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: 59fc630b8b5f ("RAID5: batch adjacent full stripe write")
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9ffc8f7c |
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18-Mar-2015 |
Eric Mei <eric.mei@seagate.com> |
md/raid5: don't do chunk aligned read on degraded array. When array is degraded, read data landed on failed drives will result in reading rest of data in a stripe. So a single sequential read would result in same data being read twice. This patch is to avoid chunk aligned read for degraded array. The downside is to involve stripe cache which means associated CPU overhead and extra memory copy. Test Results: Following test are done on a enterprise storage node with Seagate 6T SAS drives and Xeon E5-2648L CPU (10 cores, 1.9Ghz), 10 disks MD RAID6 8+2, chunk size 128 KiB. I use FIO, using direct-io with various bs size, enough queue depth, tested sequential and 100% random read against 3 array config: 1) optimal, as baseline; 2) degraded; 3) degraded with this patch. Kernel version is 4.0-rc3. Each individual test I only did once so there might be some variations, but we just focus on big trend. Sequential Read: bs=(KiB) optimal(MiB/s) degraded(MiB/s) degraded-with-patch (MiB/s) 1024 1608 656 995 512 1624 710 956 256 1635 728 980 128 1636 771 983 64 1612 1119 1000 32 1580 1420 1004 16 1368 688 986 8 768 647 953 4 411 413 850 Random Read: bs=(KiB) optimal(IOPS) degraded(IOPS) degraded-with-patch (IOPS) 1024 163 160 156 512 274 273 272 256 426 428 424 128 576 592 591 64 726 724 726 32 849 848 837 16 900 970 971 8 927 940 929 4 948 940 955 Some notes: * In sequential + optimal, as bs size getting smaller, the FIO thread become CPU bound. * In sequential + degraded, there's big increase when bs is 64K and 32K, I don't have explanation. * In sequential + degraded-with-patch, the MD thread mostly become CPU bound. If you want to we can discuss specific data point in those data. But in general it seems with this patch, we have more predictable and in most cases significant better sequential read performance when array is degraded, and almost no noticeable impact on random read. Performance is a complicated thing, the patch works well for this particular configuration, but may not be universal. For example I imagine testing on all SSD array may have very different result. But I personally think in most cases IO bandwidth is more scarce resource than CPU. Signed-off-by: Eric Mei <eric.mei@seagate.com> Signed-off-by: NeilBrown <neilb@suse.de>
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edbe83ab |
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25-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: allow the stripe_cache to grow and shrink. The default setting of 256 stripe_heads is probably much too small for many configurations. So it is best to make it auto-configure. Shrinking the cache under memory pressure is easy. The only interesting part here is that we put a fairly high cost ('seeks') on shrinking the cache as the cost is greater than just having to read more data, it reduces parallelism. Growing the cache on demand needs to be done carefully. If we allow fast growth, that can upset memory balance as lots of dirty memory can quickly turn into lots of memory queued in the stripe_cache. It is important for the raid5 block device to appear congested to allow write-throttling to work. So we only add stripes slowly. We set a flag when an allocation fails because all stripes are in use, allocate at a convenient time when that flag is set, and don't allow it to be set again until at least one stripe_head has been released for re-use. This means that a spurt of requests will only cause one stripe_head to be allocated, but a steady stream of requests will slowly increase the cache size - until memory pressure puts it back again. It could take hours to reach a steady state. The value written to, and displayed in, stripe_cache_size is used as a minimum. The cache can grow above this and shrink back down to it. The actual size is not directly visible, though it can be deduced to some extent by watching stripe_cache_active. Signed-off-by: NeilBrown <neilb@suse.de>
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5423399a |
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25-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: change ->inactive_blocked to a bit-flag. This allows us to easily add more (atomic) flags. Signed-off-by: NeilBrown <neilb@suse.de>
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486f0644 |
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24-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: move max_nr_stripes management into grow_one_stripe and drop_one_stripe Rather than adjusting max_nr_stripes whenever {grow,drop}_one_stripe() succeeds, do it inside the functions. Also choose the correct hash to handle next inside the functions. This removes duplication and will help with future new uses of {grow,drop}_one_stripe. This also fixes a minor bug where the "md/raid:%md: allocate XXkB" message always said "0kB". Signed-off-by: NeilBrown <neilb@suse.de>
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a9683a79 |
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24-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: pass gfp_t arg to grow_one_stripe() This is needed for future improvement to stripe cache management. Signed-off-by: NeilBrown <neilb@suse.de>
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d06f191f |
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14-Dec-2014 |
Markus Stockhausen <stockhausen@collogia.de> |
md/raid5: introduce configuration option rmw_level Depending on the available coding we allow optimized rmw logic for write operations. To support easier testing this patch allows manual control of the rmw/rcw descision through the interface /sys/block/mdX/md/rmw_level. The configuration can handle three levels of control. rmw_level=0: Disable rmw for all RAID types. Hardware assisted P/Q calculation has no implementation path yet to factor in/out chunks of a syndrome. Enforcing this level can be benefical for slow CPUs with hardware syndrome support and fast SSDs. rmw_level=1: Estimate rmw IOs and rcw IOs. Execute rmw only if we will save IOs. This equals the "old" unpatched behaviour and will be the default. rmw_level=2: Execute rmw even if calculated IOs for rmw and rcw are equal. We might have higher CPU consumption because of calculating the parity twice but it can be benefical otherwise. E.g. RAID4 with fast dedicated parity disk/SSD. The option is implemented just to be forward-looking and will ONLY work with this patch! Signed-off-by: Markus Stockhausen <stockhausen@collogia.de> Signed-off-by: NeilBrown <neilb@suse.de>
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584acdd4 |
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14-Dec-2014 |
Markus Stockhausen <stockhausen@collogia.de> |
md/raid5: activate raid6 rmw feature Glue it altogehter. The raid6 rmw path should work the same as the already existing raid5 logic. So emulate the prexor handling/flags and split functions as needed. 1) Enable xor_syndrome() in the async layer. 2) Split ops_run_prexor() into RAID4/5 and RAID6 logic. Xor the syndrome at the start of a rmw run as we did it before for the single parity. 3) Take care of rmw run in ops_run_reconstruct6(). Again process only the changed pages to get syndrome back into sync. 4) Enhance set_syndrome_sources() to fill NULL pages if we are in a rmw run. The lower layers will calculate start & end pages from that and call the xor_syndrome() correspondingly. 5) Adapt the several places where we ignored Q handling up to now. Performance numbers for a single E5630 system with a mix of 10 7200k desktop/server disks. 300 seconds random write with 8 threads onto a 3,2TB (10*400GB) RAID6 64K chunk without spare (group_thread_cnt=4) bsize rmw_level=1 rmw_level=0 rmw_level=1 rmw_level=0 skip_copy=1 skip_copy=1 skip_copy=0 skip_copy=0 4K 115 KB/s 141 KB/s 165 KB/s 140 KB/s 8K 225 KB/s 275 KB/s 324 KB/s 274 KB/s 16K 434 KB/s 536 KB/s 640 KB/s 534 KB/s 32K 751 KB/s 1,051 KB/s 1,234 KB/s 1,045 KB/s 64K 1,339 KB/s 1,958 KB/s 2,282 KB/s 1,962 KB/s 128K 2,673 KB/s 3,862 KB/s 4,113 KB/s 3,898 KB/s 256K 7,685 KB/s 7,539 KB/s 7,557 KB/s 7,638 KB/s 512K 19,556 KB/s 19,558 KB/s 19,652 KB/s 19,688 Kb/s Signed-off-by: Markus Stockhausen <stockhausen@collogia.de> Signed-off-by: NeilBrown <neilb@suse.de>
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dabc4ec6 |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
raid5: handle expansion/resync case with stripe batching expansion/resync can grab a stripe when the stripe is in batch list. Since all stripes in batch list must be in the same state, we can't allow some stripes run into expansion/resync. So we delay expansion/resync for stripe in batch list. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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72ac7330 |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
raid5: handle io error of batch list If io error happens in any stripe of a batch list, the batch list will be split, then normal process will run for the stripes in the list. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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59fc630b |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
RAID5: batch adjacent full stripe write stripe cache is 4k size. Even adjacent full stripe writes are handled in 4k unit. Idealy we should use big size for adjacent full stripe writes. Bigger stripe cache size means less stripes runing in the state machine so can reduce cpu overhead. And also bigger size can cause bigger IO size dispatched to under layer disks. With below patch, we will automatically batch adjacent full stripe write together. Such stripes will be added to the batch list. Only the first stripe of the list will be put to handle_list and so run handle_stripe(). Some steps of handle_stripe() are extended to cover all stripes of the list, including ops_run_io, ops_run_biodrain and so on. With this patch, we have less stripes running in handle_stripe() and we send IO of whole stripe list together to increase IO size. Stripes added to a batch list have some limitations. A batch list can only include full stripe write and can't cross chunk boundary to make sure stripes have the same parity disks. Stripes in a batch list must be in the same state (no written, toread and so on). If a stripe is in a batch list, all new read/write to add_stripe_bio will be blocked to overlap conflict till the batch list is handled. The limitations will make sure stripes in a batch list be in exactly the same state in the life circly. I did test running 160k randwrite in a RAID5 array with 32k chunk size and 6 PCIe SSD. This patch improves around 30% performance and IO size to under layer disk is exactly 32k. I also run a 4k randwrite test in the same array to make sure the performance isn't changed with the patch. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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7a87f434 |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
raid5: track overwrite disk count Track overwrite disk count, so we can know if a stripe is a full stripe write. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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da41ba65 |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
raid5: add a new flag to track if a stripe can be batched A freshly new stripe with write request can be batched. Any time the stripe is handled or new read is queued, the flag will be cleared. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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46d5b785 |
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14-Dec-2014 |
shli@kernel.org <shli@kernel.org> |
raid5: use flex_array for scribble data Use flex_array for scribble data. Next patch will batch several stripes together, so scribble data should be able to cover several stripes, so this patch also allocates scribble data for stripes across a chunk. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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09314799 |
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18-Feb-2015 |
NeilBrown <neilb@suse.de> |
md: remove 'go_faster' option from ->sync_request() This option is not well justified and testing suggests that it hardly ever makes any difference. The comment suggests there might be a need to wait for non-resync activity indicated by ->nr_waiting, however raise_barrier() already waits for all of that. So just remove it to simplify reasoning about speed limiting. This allows us to remove a 'FIXME' comment from raid5.c as that never used the flag. Signed-off-by: NeilBrown <neilb@suse.de>
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16d9cfab |
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06-Jan-2015 |
Eric Mei <eric.mei@seagate.com> |
raid5: check faulty flag for array status during recovery. When we have more than 1 drive failure, it's possible we start rebuild one drive while leaving another faulty drive in array. To determine whether array will be optimal after building, current code only check whether a drive is missing, which could potentially lead to data corruption. This patch is to add checking Faulty flag. Signed-off-by: NeilBrown <neilb@suse.de>
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26ac1073 |
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17-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: Fix livelock when array is both resyncing and degraded. Commit a7854487cd7128a30a7f4f5259de9f67d5efb95f: md: When RAID5 is dirty, force reconstruct-write instead of read-modify-write. Causes an RCW cycle to be forced even when the array is degraded. A degraded array cannot support RCW as that requires reading all data blocks, and one may be missing. Forcing an RCW when it is not possible causes a live-lock and the code spins, repeatedly deciding to do something that cannot succeed. So change the condition to only force RCW on non-degraded arrays. Reported-by: Manibalan P <pmanibalan@amiindia.co.in> Bisected-by: Jes Sorensen <Jes.Sorensen@redhat.com> Tested-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Fixes: a7854487cd7128a30a7f4f5259de9f67d5efb95f Cc: stable@vger.kernel.org (v3.7+)
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6791875e |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md: make reconfig_mutex optional for writes to md sysfs files. Rather than using mddev_lock() to take the reconfig_mutex when writing to any md sysfs file, we only take mddev_lock() in the particular _store() functions that require it. Admittedly this is most, but it isn't all. This also allows us to remove special-case handling for new_dev_store (in md_attr_store). Signed-off-by: NeilBrown <neilb@suse.de>
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7b1485ba |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: use ->lock to protect accessing raid5 sysfs attributes. It is important that mddev->private isn't freed while a sysfs attribute function is accessing it. So use mddev->lock to protect the setting of ->private to NULL, and take that lock when checking ->private for NULL and de-referencing it in the sysfs access functions. This only applies to the read ('show') side of access. Write access will be handled separately. Signed-off-by: NeilBrown <neilb@suse.de>
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afa0f557 |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md: rename ->stop to ->free Now that the ->stop function only frees the private data, rename is accordingly. Also pass in the private pointer as an arg rather than using mddev->private. This flexibility will be useful in level_store(). Finally, don't clear ->private. It doesn't make sense to clear it seeing that isn't what we free, and it is no longer necessary to clear ->private (it was some time ago before ->to_remove was introduced). Setting ->to_remove in ->free() is a bit of a wart, but not a big problem at the moment. Signed-off-by: NeilBrown <neilb@suse.de>
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5aa61f42 |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md: split detach operation out from ->stop. Each md personality has a 'stop' operation which does two things: 1/ it finalizes some aspects of the array to ensure nothing is accessing the ->private data 2/ it frees the ->private data. All the steps in '1' can apply to all arrays and so can be performed in common code. This is useful as in the case where we change the personality which manages an array (in level_store()), it would be helpful to do step 1 early, and step 2 later. So split the 'step 1' functionality out into a new mddev_detach(). Signed-off-by: NeilBrown <neilb@suse.de>
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64590f45 |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md: make merge_bvec_fn more robust in face of personality changes. There is no locking around calls to merge_bvec_fn(), so it is possible that calls which coincide with a level (or personality) change could go wrong. So create a central dispatch point for these functions and use rcu_read_lock(). If the array is suspended, reject any merge that can be rejected. If not, we know it is safe to call the function. Signed-off-by: NeilBrown <neilb@suse.de>
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5c675f83 |
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14-Dec-2014 |
NeilBrown <neilb@suse.de> |
md: make ->congested robust against personality changes. There is currently no locking around calls to the 'congested' bdi function. If called at an awkward time while an array is being converted from one level (or personality) to another, there is a tiny chance of running code in an unreferenced module etc. So add a 'congested' function to the md_personality operations structure, and call it with appropriate locking from a central 'mddev_congested'. When the array personality is changing the array will be 'suspended' so no IO is processed. If mddev_congested detects this, it simply reports that the array is congested, which is a safe guess. As mddev_suspend calls synchronize_rcu(), mddev_congested can avoid races by included the whole call inside an rcu_read_lock() region. This require that the congested functions for all subordinate devices can be run under rcu_lock. Fortunately this is the case. Signed-off-by: NeilBrown <neilb@suse.de>
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ea664c82 |
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01-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: need_this_block: tidy/fix last condition. That last condition is unclear and over cautious. There are two related issues here. If a partial write is destined for a missing device, then either RMW or RCW can work. We must read all the available block. Only then can the missing blocks be calculated, and then the parity update performed. If RMW is not an option, then there is a complication even without partial writes. If we would need to read a missing device to perform the reconstruction, then we must first read every block so the missing device data can be computed. This is the case for RAID6 (Which currently does not support RMW) and for times when we don't trust the parity (after a crash) and so are in the process of resyncing it. So make these two cases more clear and separate, and perform the relevant tests more thoroughly. Signed-off-by: NeilBrown <neilb@suse.de>
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a9d56950 |
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01-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: need_this_block: start simplifying the last two conditions. Both the last two cases are only relevant if something has failed and something needs to be written (but not over-written), and if it is OK to pre-read blocks at this point. So factor out those tests and explain them. Signed-off-by: NeilBrown <neilb@suse.de>
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a79cfe12 |
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01-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: separate out the easy conditions in need_this_block. Some of the conditions in need_this_block have very straight forward motivation. Separate those out and document them. Signed-off-by: NeilBrown <neilb@suse.de>
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2c58f06e |
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01-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: separate large if clause out of fetch_block(). fetch_block() has a very large and hard to read 'if' condition. Separate it into its own function so that it can be made more readable. Signed-off-by: NeilBrown <neilb@suse.de>
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ad3ab8b6 |
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28-Jan-2015 |
Jes Sorensen <Jes.Sorensen@redhat.com> |
md: do_release_stripe(): No need to call md_wakeup_thread() twice 67f455486d2ea20b2d94d6adf5b9b783d079e321 introduced a call to md_wakeup_thread() when adding to the delayed_list. However the md thread is woken up unconditionally just below. Remove the unnecessary wakeup call. Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b1b02fe9 |
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01-Feb-2015 |
NeilBrown <neilb@suse.de> |
md/raid5: fix another livelock caused by non-aligned writes. If a non-page-aligned write is destined for a device which is missing/faulty, we can deadlock. As the target device is missing, a read-modify-write cycle is not possible. As the write is not for a full-page, a recontruct-write cycle is not possible. This should be handled by logic in fetch_block() which notices there is a non-R5_OVERWRITE write to a missing device, and so loads all blocks. However since commit 67f455486d2ea2, that code requires STRIPE_PREREAD_ACTIVE before it will active, and those circumstances never set STRIPE_PREREAD_ACTIVE. So: in handle_stripe_dirtying, if neither rmw or rcw was possible, set STRIPE_DELAYED, which will cause STRIPE_PREREAD_ACTIVE be set after a suitable delay. Fixes: 67f455486d2ea20b2d94d6adf5b9b783d079e321 Cc: stable@vger.kernel.org (v3.16+) Reported-by: Mikulas Patocka <mpatocka@redhat.com> Tested-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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108cef3a |
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02-Dec-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: fetch_block must fetch all the blocks handle_stripe_dirtying wants. It is critical that fetch_block() and handle_stripe_dirtying() are consistent in their analysis of what needs to be loaded. Otherwise raid5 can wait forever for a block that won't be loaded. Currently when writing to a RAID5 that is resyncing, to a location beyond the resync offset, handle_stripe_dirtying chooses a reconstruct-write cycle, but fetch_block() assumes a read-modify-write, and a lockup can happen. So treat that case just like RAID6, just as we do in handle_stripe_dirtying. RAID6 always does reconstruct-write. This bug was introduced when the behaviour of handle_stripe_dirtying was changed in 3.7, so the patch is suitable for any kernel since, though it will need careful merging for some versions. Cc: stable@vger.kernel.org (v3.7+) Fixes: a7854487cd7128a30a7f4f5259de9f67d5efb95f Reported-by: Henry Cai <henryplusplus@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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f72ffdd6 |
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29-Sep-2014 |
NeilBrown <neilb@suse.de> |
md: remove unwanted white space from md.c My editor shows much of this is RED. Signed-off-by: NeilBrown <neilb@suse.de>
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b8e6a15a |
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23-Aug-2014 |
Markus Stockhausen <stockhausen@collogia.de> |
md/raid5: fix init_stripe() inconsistencies raid5: fix init_stripe() inconsistencies 1) remove_hash() is not necessary. We will only be called right after get_free_stripe(). There we have already a call to remove_hash(). 2) Tracing prints out the sector of the freed stripe and not the sector that we want to initialize. Signed-off-by: NeilBrown <neilb@suse.de>
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3fd83717 |
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23-Aug-2014 |
NeilBrown <neilb@suse.de> |
md: use set_bit/clear_bit instead of shift/mask for bi_flags changes. Using {set,clear}_bit is more consistent than shifting and masking. No functional change. Signed-off-by: NeilBrown <neilb@suse.de>
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8e0e99ba |
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01-Oct-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: disable 'DISCARD' by default due to safety concerns. It has come to my attention (thanks Martin) that 'discard_zeroes_data' is only a hint. Some devices in some cases don't do what it says on the label. The use of DISCARD in RAID5 depends on reads from discarded regions being predictably zero. If a write to a previously discarded region performs a read-modify-write cycle it assumes that the parity block was consistent with the data blocks. If all were zero, this would be the case. If some are and some aren't this would not be the case. This could lead to data corruption after a device failure when data needs to be reconstructed from the parity. As we cannot trust 'discard_zeroes_data', ignore it by default and so disallow DISCARD on all raid4/5/6 arrays. As many devices are trustworthy, and as there are benefits to using DISCARD, add a module parameter to over-ride this caution and cause DISCARD to work if discard_zeroes_data is set. If a site want to enable DISCARD on some arrays but not on others they should select DISCARD support at the filesystem level, and set the raid456 module parameter. raid456.devices_handle_discard_safely=Y As this is a data-safety issue, I believe this patch is suitable for -stable. DISCARD support for RAID456 was added in 3.7 Cc: Shaohua Li <shli@kernel.org> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Heinz Mauelshagen <heinzm@redhat.com> Cc: stable@vger.kernel.org (3.7+) Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Fixes: 620125f2bf8ff0c4969b79653b54d7bcc9d40637 Signed-off-by: NeilBrown <neilb@suse.de>
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9c4bdf69 |
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12-Aug-2014 |
NeilBrown <neilb@suse.de> |
md/raid6: avoid data corruption during recovery of double-degraded RAID6 During recovery of a double-degraded RAID6 it is possible for some blocks not to be recovered properly, leading to corruption. If a write happens to one block in a stripe that would be written to a missing device, and at the same time that stripe is recovering data to the other missing device, then that recovered data may not be written. This patch skips, in the double-degraded case, an optimisation that is only safe for single-degraded arrays. Bug was introduced in 2.6.32 and fix is suitable for any kernel since then. In an older kernel with separate handle_stripe5() and handle_stripe6() functions the patch must change handle_stripe6(). Cc: stable@vger.kernel.org (2.6.32+) Fixes: 6c0069c0ae9659e3a91b68eaed06a5c6c37f45c8 Cc: Yuri Tikhonov <yur@emcraft.com> Cc: Dan Williams <dan.j.williams@intel.com> Reported-by: "Manibalan P" <pmanibalan@amiindia.co.in> Tested-by: "Manibalan P" <pmanibalan@amiindia.co.in> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1090423 Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Dan Williams <dan.j.williams@intel.com>
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a40687ff |
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12-Aug-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: avoid livelock caused by non-aligned writes. If a stripe in a raid6 array received a write to each data block while the array is degraded, and if any of these writes to a missing device are not page-aligned, then a live-lock happens. In this case the P and Q blocks need to be read so that the part of the missing block which is *not* being updated by the write can be constructed. Due to a logic error, these blocks are not loaded, so the update cannot proceed and the stripe is 'handled' repeatedly in an infinite loop. This bug is unlikely as most writes are page aligned. However as it can lead to a livelock it is suitable for -stable. It was introduced in 3.16. Cc: stable@vger.kernel.org (v3.16) Fixed: 67f455486d2ea20b2d94d6adf5b9b783d079e321 Signed-off-by: NeilBrown <neilb@suse.de>
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#
053f5b65 |
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09-Jun-2014 |
Eivind Sarto <eivindsarto@gmail.com> |
raid5: speedup sync_request processing The raid5 sync_request() processing calls handle_stripe() within the context of the resync-thread. The resync-thread issues the first set of read requests and this adds execution latency and slows down the scheduling of the next sync_request(). The current rebuild/resync speed of raid5 is not much faster than what rotational HDDs can sustain. Testing the following patch on a 6-drive array, I can increase the rebuild speed from 100 MB/s to 175 MB/s. The sync_request() now just sets STRIPE_HANDLE and releases the stripe. This creates some more parallelism between the resync-thread and raid5 kernel daemon. Signed-off-by: Eivind Sarto <esarto@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
2844dc32 |
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04-Jun-2014 |
hui jiao <simonjiaoh@gmail.com> |
md/raid5: deadlock between retry_aligned_read with barrier io A chunk aligned read increases counter active_aligned_reads and decreases it after sub-device handle it successfully. But when a read error occurs, the read redispatched by raid5d, and the active_aligned_reads will not be decreased until we can grab a stripe head in retry_aligned_read. Now suppose, a barrier io comes, set conf->quiesce to 2, and wait until both active_stripes and active_aligned_reads are zero. The retried chunk aligned read gets stuck at get_active_stripe waiting until conf->quiesce becomes 0. Retry_aligned_read and barrier io are waiting each other now. One possible solution is that we ignore conf->quiesce, let the retried aligned read finish. I reproduced this deadlock and test this patch on centos6.0 Signed-off-by: NeilBrown <neilb@suse.de>
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#
d592a996 |
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21-May-2014 |
Shaohua Li <shli@kernel.org> |
raid5: add an option to avoid copy data from bio to stripe cache The stripe cache has two goals: 1. cache data, so next time if data can be found in stripe cache, disk access can be avoided. 2. stable data. data is copied from bio to stripe cache and calculated parity. data written to disk is from stripe cache, so if upper layer changes bio data, data written to disk isn't impacted. In my environment, I can guarantee 2 will not happen. And BDI_CAP_STABLE_WRITES can guarantee 2 too. For 1, it's not common too. block plug mechanism will dispatch a bunch of sequentail small requests together. And since I'm using SSD, I'm using small chunk size. It's rare case stripe cache is really useful. So I'd like to avoid the copy from bio to stripe cache and it's very helpful for performance. In my 1M randwrite tests, avoid the copy can increase the performance more than 30%. Of course, this shouldn't be enabled by default. It's reported enabling BDI_CAP_STABLE_WRITES can harm some workloads before, so I added an option to control it. Neilb: changed BUG_ON to WARN_ON Removed some assignments from raid5_build_block which are now not needed. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
cf170f3f |
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27-May-2014 |
Eivind Sarto <eivindsarto@gmail.com> |
raid5: avoid release list until last reference of the stripe The (lockless) release_list reduces lock contention, but there is excessive queueing and dequeuing of stripes on this list. A stripe will currently be queued on the release_list with a stripe reference count > 1. This can cause the raid5 kernel thread(s) to dequeue the stripe and decrement the refcount without doing any other useful processing of the stripe. The are two cases when the stripe can be put on the release_list multiple times before it is actually handled by the kernel thread(s). 1) make_request() activates the stripe processing in 4k increments. When a write request is large enough to span multiple chunks of a stripe_head, the first 4k chunk adds the stripe to the plug list. The next 4k chunk that is processed for the same stripe puts the stripe on the release_list with a refcount=2. This can cause the kernel thread to process and decrement the stripe before the stripe us unplugged, which again will put it back on the release_list. 2) Whenever IO is scheduled on a stripe (pre-read and/or write), the stripe refcount is set to the number of active IO (for each chunk). The stripe is released as each IO complete, and can be queued and dequeued multiple times on the release_list, until its refcount finally reached zero. This simple patch will ensure a stripe is only queued on the release_list when its refcount=1 and is ready to be handled by the kernel thread(s). I added some instrumentation to raid5 and counted the number of times striped were queued on the release_list for a variety of write IO sizes. Without this patch the number of times stripes got queued on the release_list was 100-500% higher than with the patch. The excess queuing will increase with the IO size. The patch also improved throughput by 5-10%. Signed-off-by: Eivind Sarto <esarto@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
67f45548 |
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27-May-2014 |
NeilBrown <neilb@suse.de> |
md/raid56: Don't perform reads to support writes until stripe is ready. If it is found that we need to pre-read some blocks before a write can succeed, we normally set STRIPE_DELAYED and don't actually perform the read until STRIPE_PREREAD_ACTIVE subsequently gets set. However for a degraded RAID6 we currently perform the reads as soon as we see that a write is pending. This significantly hurts throughput. So: - when handle_stripe_dirtying find a block that it wants on a device that is failed, set STRIPE_DELAY, instead of doing nothing, and - when fetch_block detects that a read might be required to satisfy a write, only perform the read if STRIPE_PREREAD_ACTIVE is set, and if we would actually need to read something to complete the write. This also helps RAID5, though less often as RAID5 supports a read-modify-write cycle. For RAID5 the read is performed too early only if the write is not a full 4K aligned write (i.e. no an R5_OVERWRITE). Also clean up a couple of horrible bits of formatting. Reported-by: Patrik HornÃk <patrik@dsl.sk> Signed-off-by: NeilBrown <neilb@suse.de>
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#
4e857c58 |
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17-Mar-2014 |
Peter Zijlstra <peterz@infradead.org> |
arch: Mass conversion of smp_mb__*() Mostly scripted conversion of the smp_mb__* barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
c7a6d35e |
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14-Apr-2014 |
Shaohua Li <shli@kernel.org> |
raid5: fix a race of stripe count check I hit another BUG_ON with e240c1839d11152b0355442. In __get_priority_stripe(), stripe count equals to 0 initially. Between atomic_inc and BUG_ON, get_active_stripe() finds the stripe. So the stripe count isn't 1 any more. V2: keeps the BUG_ON suggested by Neil. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
e240c183 |
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08-Apr-2014 |
Shaohua Li <shli@kernel.org> |
raid5: get_active_stripe avoids device_lock For sequential workload (or request size big workload), get_active_stripe can find cached stripe. In this case, we always hold device_lock, which exposes a lot of lock contention for such workload. If stripe count isn't 0, we don't need hold the lock actually, since we just increase its count. And this is the hot code path for such workload. Unfortunately we must delete the BUG_ON. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
27c0f68f |
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08-Apr-2014 |
Shaohua Li <shli@kernel.org> |
raid5: make_request does less prepare wait In NUMA machine, prepare_to_wait/finish_wait in make_request exposes a lot of contention for sequential workload (or big request size workload). For such workload, each bio includes several stripes. So we can just do prepare_to_wait/finish_wait once for the whold bio instead of every stripe. This reduces the lock contention completely for such workload. Random workload might have the similar lock contention too, but I didn't see it yet, maybe because my stroage is still not fast enough. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
789b5e03 |
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05-Feb-2014 |
Oleg Nesterov <oleg@redhat.com> |
md/raid5: Fix CPU hotplug callback registration Subsystems that want to register CPU hotplug callbacks, as well as perform initialization for the CPUs that are already online, often do it as shown below: get_online_cpus(); for_each_online_cpu(cpu) init_cpu(cpu); register_cpu_notifier(&foobar_cpu_notifier); put_online_cpus(); This is wrong, since it is prone to ABBA deadlocks involving the cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently with CPU hotplug operations). Interestingly, the raid5 code can actually prevent double initialization and hence can use the following simplified form of callback registration: register_cpu_notifier(&foobar_cpu_notifier); get_online_cpus(); for_each_online_cpu(cpu) init_cpu(cpu); put_online_cpus(); A hotplug operation that occurs between registering the notifier and calling get_online_cpus(), won't disrupt anything, because the code takes care to perform the memory allocations only once. So reorganize the code in raid5 this way to fix the deadlock with callback registration. Cc: linux-raid@vger.kernel.org Cc: stable@vger.kernel.org (v2.6.32+) Fixes: 36d1c6476be51101778882897b315bd928c8c7b5 Signed-off-by: Oleg Nesterov <oleg@redhat.com> [Srivatsa: Fixed the unregister_cpu_notifier() deadlock, added the free_scratch_buffer() helper to condense code further and wrote the changelog.] Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
7da9d450 |
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21-Jan-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: close recently introduced race in stripe_head management. As release_stripe and __release_stripe decrement ->count and then manipulate ->lru both under ->device_lock, it is important that get_active_stripe() increments ->count and clears ->lru also under ->device_lock. However we currently list_del_init ->lru under the lock, but increment the ->count outside the lock. This can lead to races and list corruption. So move the atomic_inc(&sh->count) up inside the ->device_lock protected region. Note that we still increment ->count without device lock in the case where get_free_stripe() was called, and in fact don't take ->device_lock at all in that path. This is safe because if the stripe_head can be found by get_free_stripe, then the hash lock assures us the no-one else could possibly be calling release_stripe() at the same time. Fixes: 566c09c53455d7c4f1130928ef8071da1a24ea65 Cc: stable@vger.kernel.org (3.13) Reported-and-tested-by: Ian Kumlien <ian.kumlien@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
9f97e4b1 |
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15-Jan-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: fix long-standing problem with bitmap handling on write failure. Before a write starts we set a bit in the write-intent bitmap. When the write completes we clear that bit if the write was successful to all devices. However if the write wasn't fully successful we should not clear the bit. If the faulty drive is subsequently re-added, the fact that the bit is still set ensure that we will re-write the data that is missing. This logic is mediated by the STRIPE_DEGRADED flag - we only clear the bitmap bit when this flag is not set. Currently we correctly set the flag if a write starts when some devices are failed or missing. But we do *not* set the flag if some device failed during the write attempt. This is wrong and can result in clearing the bit inappropriately. So: set the flag when a write fails. This bug has been present since bitmaps were introduces, so the fix is suitable for any -stable kernel. Reported-by: Ethan Wilson <ethan.wilson@shiftmail.org> Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
5af9bef7 |
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13-Jan-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: fix a recently broken BUG_ON(). commit 6d183de4077191d1201283a9035ce57a9b05254d md/raid5: fix newly-broken locking in get_active_stripe. simplified a BUG_ON, but removed too much so now it sometimes fires when it shouldn't. When the STRIPE_EXPANDING flag is set, the stripe_head might be on a special list while multiple stripe_heads are collected, or it might not be on any list, even a 'free' list when the refcount is zero. As long as STRIPE_EXPANDING is set, it will be found and added back to a list eventually. So both of the BUG_ONs which test for the ->lru being empty or not need to avoid the case where STRIPE_EXPANDING is set. The patch which broke this was marked for -stable, so this patch needs to be applied to any branch that received 6d183de4 Fixes: 6d183de4077191d1201283a9035ce57a9b05254d Cc: stable@vger.kernel.org (any release to which above was applied) Signed-off-by: NeilBrown <neilb@suse.de>
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#
1cc03eb9 |
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05-Jan-2014 |
NeilBrown <neilb@suse.de> |
md/raid5: Fix possible confusion when multiple write errors occur. commit 5d8c71f9e5fbdd95650be00294d238e27a363b5c md: raid5 crash during degradation Fixed a crash in an overly simplistic way which could leave R5_WriteError or R5_MadeGood set in the stripe cache for devices for which it is no longer relevant. When those devices are removed and spares added the flags are still set and can cause incorrect behaviour. commit 14a75d3e07c784c004b4b44b34af996b8e4ac453 md/raid5: preferentially read from replacement device if possible. Fixed the same bug if a more effective way, so we can now revert the original commit. Reported-and-tested-by: Alexander Lyakas <alex.bolshoy@gmail.com> Cc: stable@vger.kernel.org (3.2+ - 3.2 will need a different fix though) Fixes: 5d8c71f9e5fbdd95650be00294d238e27a363b5c Signed-off-by: NeilBrown <neilb@suse.de>
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#
c78afc62 |
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11-Jul-2013 |
Kent Overstreet <kmo@daterainc.com> |
bcache/md: Use raid stripe size Now that we've got code for raid5/6 stripe awareness, bcache just needs to know about the stripes and when writing partial stripes is expensive - we probably don't want to enable this optimization for raid1 or 10, even though they have stripes. So add a flag to queue_limits. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
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#
6d183de4 |
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27-Nov-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: fix newly-broken locking in get_active_stripe. commit 566c09c53455d7c4f1 raid5: relieve lock contention in get_active_stripe() modified the locking in get_active_stripe() reducing the range protected by the (highly contended) device_lock. Unfortunately it reduced the range too much opening up some races. One race can occur if get_priority_stripe runs between the test on sh->count and device_lock being taken. This will mean that sh->lru is not empty while get_active_stripe thinks ->count is zero resulting in a 'BUG' firing. Another race happens if __release_stripe is called immediately after sh->count is tested and found to be non-zero. If STRIPE_HANDLE is not set, get_active_stripe should increment ->active_stripes when it increments ->count from 0, but as it didn't think it was 0, it doesn't. Extending device_lock to cover the test on sh->count close these races. While we are here, fix the two BUG tests: -If count is zero, then lru really must not be empty, or we've lock the stripe_head somehow - no other tests are relevant. -STRIPE_ON_RELEASE_LIST is completely independent of ->lru so testing it is pointless. Reported-and-tested-by: Brassow Jonathan <jbrassow@redhat.com> Reviewed-by: Shaohua Li <shli@kernel.org> Fixes: 566c09c53455d7c4f1 Signed-off-by: NeilBrown <neilb@suse.de>
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#
0c775d52 |
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24-Nov-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: fix new memory-reference bug in alloc_thread_groups. In alloc_thread_groups, worker_groups is a pointer to an array, not an array of pointers. So worker_groups[i] is wrong. It should be &(*worker_groups)[i] Found-by: coverity Fixes: 60aaf9338545 Reported-by: Ben Hutchings <bhutchings@solarflare.com> Cc: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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7988613b |
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23-Nov-2013 |
Kent Overstreet <kmo@daterainc.com> |
block: Convert bio_for_each_segment() to bvec_iter More prep work for immutable biovecs - with immutable bvecs drivers won't be able to use the biovec directly, they'll need to use helpers that take into account bio->bi_iter.bi_bvec_done. This updates callers for the new usage without changing the implementation yet. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Paul Clements <Paul.Clements@steeleye.com> Cc: Jim Paris <jim@jtan.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com> Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com> Cc: support@lsi.com Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jan Kara <jack@suse.cz> Cc: linux-m68k@lists.linux-m68k.org Cc: linuxppc-dev@lists.ozlabs.org Cc: drbd-user@lists.linbit.com Cc: nbd-general@lists.sourceforge.net Cc: cbe-oss-dev@lists.ozlabs.org Cc: xen-devel@lists.xensource.com Cc: virtualization@lists.linux-foundation.org Cc: linux-raid@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: DL-MPTFusionLinux@lsi.com Cc: linux-scsi@vger.kernel.org Cc: devel@driverdev.osuosl.org Cc: linux-fsdevel@vger.kernel.org Cc: cluster-devel@redhat.com Cc: linux-mm@kvack.org Acked-by: Geoff Levand <geoff@infradead.org>
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4f024f37 |
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11-Oct-2013 |
Kent Overstreet <kmo@daterainc.com> |
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
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60aaf933 |
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13-Nov-2013 |
majianpeng <majianpeng@gmail.com> |
md/raid5: Use conf->device_lock protect changing of multi-thread resources. When we change group_thread_cnt from sysfs entry, it can OOPS. The kernel messages are: [ 135.299021] BUG: unable to handle kernel NULL pointer dereference at (null) [ 135.299073] IP: [<ffffffff815188ab>] handle_active_stripes+0x32b/0x440 [ 135.299107] PGD 0 [ 135.299122] Oops: 0000 [#1] SMP [ 135.299144] Modules linked in: netconsole e1000e ptp pps_core [ 135.299188] CPU: 3 PID: 2225 Comm: md0_raid5 Not tainted 3.12.0+ #24 [ 135.299214] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080015 11/09/2011 [ 135.299255] task: ffff8800b9638f80 ti: ffff8800b77a4000 task.ti: ffff8800b77a4000 [ 135.299283] RIP: 0010:[<ffffffff815188ab>] [<ffffffff815188ab>] handle_active_stripes+0x32b/0x440 [ 135.299323] RSP: 0018:ffff8800b77a5c48 EFLAGS: 00010002 [ 135.299344] RAX: ffff880037bb5c70 RBX: 0000000000000000 RCX: 0000000000000008 [ 135.299371] RDX: ffff880037bb5cb8 RSI: 0000000000000001 RDI: ffff880037bb5c00 [ 135.299398] RBP: ffff8800b77a5d08 R08: 0000000000000001 R09: 0000000000000000 [ 135.299425] R10: ffff8800b77a5c98 R11: 00000000ffffffff R12: ffff880037bb5c00 [ 135.299452] R13: 0000000000000000 R14: 0000000000000000 R15: ffff880037bb5c70 [ 135.299479] FS: 0000000000000000(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000 [ 135.299510] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 135.299532] CR2: 0000000000000000 CR3: 0000000001c0b000 CR4: 00000000000407e0 [ 135.299559] Stack: [ 135.299570] ffff8800b77a5c88 ffffffff8107383e ffff8800b77a5c88 ffff880037a64300 [ 135.299611] 000000000000ec08 ffff880037bb5cb8 ffff8800b77a5c98 ffffffffffffffd8 [ 135.299654] 000000000000ec08 ffff880037bb5c60 ffff8800b77a5c98 ffff8800b77a5c98 [ 135.299696] Call Trace: [ 135.299711] [<ffffffff8107383e>] ? __wake_up+0x4e/0x70 [ 135.299733] [<ffffffff81518f88>] raid5d+0x4c8/0x680 [ 135.299756] [<ffffffff817174ed>] ? schedule_timeout+0x15d/0x1f0 [ 135.299781] [<ffffffff81524c9f>] md_thread+0x11f/0x170 [ 135.299804] [<ffffffff81069cd0>] ? wake_up_bit+0x40/0x40 [ 135.299826] [<ffffffff81524b80>] ? md_rdev_init+0x110/0x110 [ 135.299850] [<ffffffff81069656>] kthread+0xc6/0xd0 [ 135.299871] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 135.299899] [<ffffffff81722ffc>] ret_from_fork+0x7c/0xb0 [ 135.299923] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 135.299951] Code: ff ff ff 0f 84 d7 fe ff ff e9 5c fe ff ff 66 90 41 8b b4 24 d8 01 00 00 45 31 ed 85 f6 0f 8e 7b fd ff ff 49 8b 9c 24 d0 01 00 00 <48> 3b 1b 49 89 dd 0f 85 67 fd ff ff 48 8d 43 28 31 d2 eb 17 90 [ 135.300005] RIP [<ffffffff815188ab>] handle_active_stripes+0x32b/0x440 [ 135.300005] RSP <ffff8800b77a5c48> [ 135.300005] CR2: 0000000000000000 [ 135.300005] ---[ end trace 504854e5bb7562ed ]--- [ 135.300005] Kernel panic - not syncing: Fatal exception This is because raid5d() can be running when the multi-thread resources are changed via system. We see need to provide locking. mddev->device_lock is suitable, but we cannot simple call alloc_thread_groups under this lock as we cannot allocate memory while holding a spinlock. So change alloc_thread_groups() to allocate and return the data structures, then raid5_store_group_thread_cnt() can take the lock while updating the pointers to the data structures. This fixes a bug introduced in 3.12 and so is suitable for the 3.12.x stable series. Fixes: b721420e8719131896b009b11edbbd27 Cc: stable@vger.kernel.org (3.12) Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Shaohua Li <shli@kernel.org>
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#
d206dcfa |
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13-Nov-2013 |
majianpeng <majianpeng@gmail.com> |
md/raid5: Before freeing old multi-thread worker, it should flush them. When changing group_thread_cnt from sysfs entry, the kernel can oops. The kernel messages are: [ 740.961389] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 740.961444] IP: [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.961476] PGD b9013067 PUD b651e067 PMD 0 [ 740.961503] Oops: 0000 [#1] SMP [ 740.961525] Modules linked in: netconsole e1000e ptp pps_core [ 740.961577] CPU: 0 PID: 3683 Comm: kworker/u8:5 Not tainted 3.12.0+ #23 [ 740.961602] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080015 11/09/2011 [ 740.961646] task: ffff88013abe0000 ti: ffff88013a246000 task.ti: ffff88013a246000 [ 740.961673] RIP: 0010:[<ffffffff81062570>] [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.961708] RSP: 0018:ffff88013a247e08 EFLAGS: 00010086 [ 740.961730] RAX: ffff8800b912b400 RBX: ffff88013a61e680 RCX: ffff8800b912b400 [ 740.961757] RDX: ffff8800b912b600 RSI: ffff8800b912b600 RDI: ffff88013a61e680 [ 740.961782] RBP: ffff88013a247e48 R08: ffff88013a246000 R09: 000000000002c09d [ 740.961808] R10: 000000000000010f R11: 0000000000000000 R12: ffff88013b00cc00 [ 740.961833] R13: 0000000000000000 R14: ffff88013b00cf80 R15: ffff88013a61e6b0 [ 740.961861] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000 [ 740.961893] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 740.962001] CR2: 00000000000000b8 CR3: 00000000b24fe000 CR4: 00000000000407f0 [ 740.962001] Stack: [ 740.962001] 0000000000000008 ffff8800b912b600 ffff88013b00cc00 ffff88013a61e680 [ 740.962001] ffff88013b00cc00 ffff88013b00cc18 ffff88013b00cf80 ffff88013a61e6b0 [ 740.962001] ffff88013a247eb8 ffffffff810639c6 0000000000012a80 ffff88013a247fd8 [ 740.962001] Call Trace: [ 740.962001] [<ffffffff810639c6>] worker_thread+0x206/0x3f0 [ 740.962001] [<ffffffff810637c0>] ? manage_workers+0x2c0/0x2c0 [ 740.962001] [<ffffffff81069656>] kthread+0xc6/0xd0 [ 740.962001] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 740.962001] [<ffffffff81722ffc>] ret_from_fork+0x7c/0xb0 [ 740.962001] [<ffffffff81069590>] ? kthread_freezable_should_stop+0x70/0x70 [ 740.962001] Code: 89 e5 41 57 41 56 41 55 45 31 ed 41 54 53 48 89 fb 48 83 ec 18 48 8b 06 4c 8b 67 48 48 89 c1 30 c9 a8 04 4c 0f 45 e9 80 7f 58 00 <49> 8b 45 08 44 8b b0 00 01 00 00 78 0c 41 f6 44 24 10 04 0f 84 [ 740.962001] RIP [<ffffffff81062570>] process_one_work+0x30/0x500 [ 740.962001] RSP <ffff88013a247e08> [ 740.962001] CR2: 0000000000000008 [ 740.962001] ---[ end trace 39181460000748de ]--- [ 740.962001] Kernel panic - not syncing: Fatal exception This can happen if there are some stripes left, fewer than MAX_STRIPE_BATCH. A worker is queued to handle them. But before calling raid5_do_work, raid5d handles those stripes making conf->active_stripe = 0. So mddev_suspend() can return. We might then free old worker resources before the queued raid5_do_work() handled them. When it runs, it crashes. raid5d() raid5_store_group_thread_cnt() queue_work mddev_suspend() handle_strips active_stripe=0 free(old worker resources) process_one_work raid5_do_work To avoid this, we should only flush the worker resources before freeing them. This fixes a bug introduced in 3.12 so is suitable for the 3.12.x stable series. Cc: stable@vger.kernel.org (3.12) Fixes: b721420e8719131896b009b11edbbd27 Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Shaohua Li <shli@kernel.org>
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#
e59aa23f |
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13-Nov-2013 |
majianpeng <majianpeng@gmail.com> |
md/raid5: For stripe with R5_ReadNoMerge, we replace REQ_FLUSH with REQ_NOMERGE. For R5_ReadNoMerge,it mean this bio can't merge with other bios or request.It used REQ_FLUSH to achieve this. But REQ_NOMERGE can do the same work. Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
c91abf5a |
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18-Nov-2013 |
NeilBrown <neilb@suse.de> |
md: use MD_RECOVERY_INTR instead of kthread_should_stop in resync thread. We currently use kthread_should_stop() in various places in the sync/reshape code to abort early. However some places set MD_RECOVERY_INTR but don't immediately call md_reap_sync_thread() (and we will shortly get another one). When this happens we are relying on md_check_recovery() to reap the thread and that only happen when it finishes normally. So MD_RECOVERY_INTR must lead to a normal finish without the kthread_should_stop() test. So replace all relevant tests, and be more careful when the thread is interrupted not to acknowledge that latest step in a reshape as it may not be fully committed yet. Also add a test on MD_RECOVERY_INTR in the 'is_mddev_idle' loop so we don't wait have to wait for the speed to drop before we can abort. Signed-off-by: NeilBrown <neilb@suse.de>
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#
edfa1f65 |
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13-Nov-2013 |
Bian Yu <bianyu@kedacom.com> |
raid5: Retry R5_ReadNoMerge flag when hit a read error. Because of block layer merge, one bio fails will cause other bios which belongs to the same request fails, so raid5_end_read_request will record all these bios as badblocks. If retry request with R5_ReadNoMerge flag to avoid bios merge, badblocks can only record sector which is bad exactly. test: hdparm --yes-i-know-what-i-am-doing --make-bad-sector 300000 /dev/sdb mdadm -C /dev/md0 -l5 -n3 /dev/sd[bcd] --assume-clean mdadm /dev/md0 -f /dev/sdd mdadm /dev/md0 -r /dev/sdd mdadm --zero-superblock /dev/sdd mdadm /dev/md0 -a /dev/sdd 1. Without this patch: cat /sys/block/md0/md/rd*/bad_blocks 299776 256 299776 256 2. With this patch: cat /sys/block/md0/md/rd*/bad_blocks 300000 8 300000 8 Signed-off-by: Bian Yu <bianyu@kedacom.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
4bda556a |
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13-Nov-2013 |
Shaohua Li <shli@kernel.org> |
raid5: relieve lock contention in get_active_stripe() track empty inactive list count, so md_raid5_congested() can use it to make decision. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
b89241e8 |
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14-Nov-2013 |
Christoph Hellwig <hch@infradead.org> |
llists: move llist_reverse_order from raid5 to llist.c Make this useful helper available for other users. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
566c09c5 |
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13-Nov-2013 |
Shaohua Li <shli@kernel.org> |
raid5: relieve lock contention in get_active_stripe() get_active_stripe() is the last place we have lock contention. It has two paths. One is stripe isn't found and new stripe is allocated, the other is stripe is found. The first path basically calls __find_stripe and init_stripe. It accesses conf->generation, conf->previous_raid_disks, conf->raid_disks, conf->prev_chunk_sectors, conf->chunk_sectors, conf->max_degraded, conf->prev_algo, conf->algorithm, the stripe_hashtbl and inactive_list. Except stripe_hashtbl and inactive_list, other fields are changed very rarely. With this patch, we split inactive_list and add new hash locks. Each free stripe belongs to a specific inactive list. Which inactive list is determined by stripe's lock_hash. Note, even a stripe hasn't a sector assigned, it has a lock_hash assigned. Stripe's inactive list is protected by a hash lock, which is determined by it's lock_hash too. The lock_hash is derivied from current stripe_hashtbl hash, which guarantees any stripe_hashtbl list will be assigned to a specific lock_hash, so we can use new hash lock to protect stripe_hashtbl list too. The goal of the new hash locks introduced is we can only use the new locks in the first path of get_active_stripe(). Since we have several hash locks, lock contention is relieved significantly. The first path of get_active_stripe() accesses other fields, since they are changed rarely, changing them now need take conf->device_lock and all hash locks. For a slow path, this isn't a problem. If we need lock device_lock and hash lock, we always lock hash lock first. The tricky part is release_stripe and friends. We need take device_lock first. Neil's suggestion is we put inactive stripes to a temporary list and readd it to inactive_list after device_lock is released. In this way, we add stripes to temporary list with device_lock hold and remove stripes from the list with hash lock hold. So we don't allow concurrent access to the temporary list, which means we need allocate temporary list for all participants of release_stripe. One downside is free stripes are maintained in their inactive list, they can't across between the lists. By default, we have total 256 stripes and 8 lists, so each list will have 32 stripes. It's possible one list has free stripe but other list hasn't. The chance should be rare because stripes allocation are even distributed. And we can always allocate more stripes for cache, several mega bytes memory isn't a big deal. This completely removes the lock contention of the first path of get_active_stripe(). It slows down the second code path a little bit though because we now need takes two locks, but since the hash lock isn't contended, the overhead should be quite small (several atomic instructions). The second path of get_active_stripe() (basically sequential write or big request size randwrite) still has lock contentions. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
ba8805b9 |
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13-Nov-2013 |
NeilBrown <neilb@suse.de> |
md/raid5.c: add proper locking to error path of raid5_start_reshape. If raid5_start_reshape errors out, we need to reset all the fields that were updated (not just some), and need to use the seq_counter to ensure make_request() doesn't use an inconsitent state. Signed-off-by: NeilBrown <neilb@suse.de>
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ad4068de |
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13-Nov-2013 |
majianpeng <majianpeng@gmail.com> |
raid5: Use slow_path to release stripe when mddev->thread is null When release_stripe() is called in grow_one_stripe(), the mddev->thread is null. So it will omit one wakeup this thread to release stripe. For this condition, use slow_path to release stripe. Bug was introduced in 3.12 Cc: stable@vger.kernel.org (3.12+) Fixes: 773ca82fa1ee58dd1bf88b Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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d47648fc |
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19-Oct-2013 |
Shaohua Li <shli@kernel.org> |
raid5: avoid finding "discard" stripe SCSI discard will damage discard stripe bio setting, eg, some fields are changed. If the stripe is reused very soon, we have wrong bios setting. We remove discard stripe from hash list, so next time the strip will be fully initialized. Suitable for backport to 3.7+. Cc: <stable@vger.kernel.org> (3.7+) Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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37c61ff3 |
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19-Oct-2013 |
Shaohua Li <shli@kernel.org> |
raid5: set bio bi_vcnt 0 for discard request SCSI layer will add new payload for discard request. If two bios are merged to one, the second bio has bi_vcnt 1 which is set in raid5. This will confuse SCSI and cause oops. Suitable for backport to 3.7+ Cc: stable@vger.kernel.org (v3.7+) Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
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bfc90cb0 |
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29-Aug-2013 |
Shaohua Li <shli@kernel.org> |
raid5: only wakeup necessary threads If there are not enough stripes to handle, we'd better not always queue all available work_structs. If one worker can only handle small or even none stripes, it will impact request merge and create lock contention. With this patch, the number of work_struct running will depend on pending stripes number. Note: some statistics info used in the patch are accessed without locking protection. This should doesn't matter, we just try best to avoid queue unnecessary work_struct. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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4d77e3ba |
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26-Aug-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: flush out all pending requests before proceeding with reshape. Some requests - particularly 'discard' and 'read' are handled differently depending on whether a reshape is active or not. It is harmless to assume reshape is active if it isn't but wrong to act as though reshape is not active when it is. So when we start reshape - after making clear to all requests that reshape has started - use mddev_suspend/mddev_resume to flush out all requests. This will ensure that no requests will be assuming the absence of reshape once it really starts. Signed-off-by: NeilBrown <neilb@suse.de>
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c46501b2 |
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26-Aug-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: use seqcount to protect access to shape in make_request. make_request() access various shape parameters (raid_disks, chunk_size etc) which might be changed by raid5_start_reshape(). If the later is called at and awkward time during the form, the wrong stripe_head might be used. So introduce a 'seqcount' and after finding a stripe_head make sure there is no reason to expect that we got the wrong one. Signed-off-by: NeilBrown <neilb@suse.de>
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b721420e |
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27-Aug-2013 |
Shaohua Li <shli@kernel.org> |
raid5: sysfs entry to control worker thread number Add a sysfs entry to control running workqueue thread number. If group_thread_cnt is set to 0, we will disable workqueue offload handling of stripes. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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851c30c9 |
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28-Aug-2013 |
Shaohua Li <shli@kernel.org> |
raid5: offload stripe handle to workqueue This is another attempt to create multiple threads to handle raid5 stripes. This time I use workqueue. raid5 handles request (especially write) in stripe unit. A stripe is page size aligned/long and acrosses all disks. Writing to any disk sector, raid5 runs a state machine for the corresponding stripe, which includes reading some disks of the stripe, calculating parity, and writing some disks of the stripe. The state machine is running in raid5d thread currently. Since there is only one thread, it doesn't scale well for high speed storage. An obvious solution is multi-threading. To get better performance, we have some requirements: a. locality. stripe corresponding to request submitted from one cpu is better handled in thread in local cpu or local node. local cpu is preferred but some times could be a bottleneck, for example, parity calculation is too heavy. local node running has wide adaptability. b. configurablity. Different setup of raid5 array might need diffent configuration. Especially the thread number. More threads don't always mean better performance because of lock contentions. My original implementation is creating some kernel threads. There are interfaces to control which cpu's stripe each thread should handle. And userspace can set affinity of the threads. This provides biggest flexibility and configurability. But it's hard to use and apparently a new thread pool implementation is disfavor. Recent workqueue improvement is quite promising. unbound workqueue will be bound to numa node. If WQ_SYSFS is set in workqueue, there are sysfs option to do affinity setting. For example, we can only include one HT sibling in affinity. Since work is non-reentrant by default, and we can control running thread number by limiting dispatched work_struct number. In this patch, I created several stripe worker group. A group is a numa node. stripes from cpus of one node will be added to a group list. Workqueue thread of one node will only handle stripes of worker group of the node. In this way, stripe handling has numa node locality. And as I said, we can control thread number by limiting dispatched work_struct number. The work_struct callback function handles several stripes in one run. A typical work queue usage is to run one unit in each work_struct. In raid5 case, the unit is a stripe. But we can't do that: a. Though handling a stripe doesn't need lock because of reference accounting and stripe isn't in any list, queuing a work_struct for each stripe will make workqueue lock contended very heavily. b. blk_start_plug()/blk_finish_plug() should surround stripe handle, as we might dispatch request. If each work_struct only handles one stripe, such block plug is meaningless. This implementation can't do very fine grained configuration. But the numa binding is most popular usage model, should be enough for most workloads. Note: since we have only one stripe queue, switching to multi-thread might decrease request size dispatching down to low level layer. The impact depends on thread number, raid configuration and workload. So multi-thread raid5 might not be proper for all setups. Changes V1 -> V2: 1. remove WQ_NON_REENTRANT 2. disabling multi-threading by default 3. Add more descriptions in changelog Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
d265d9dc |
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28-Aug-2013 |
Shaohua Li <shli@kernel.org> |
raid5: fix stripe release order patch "make release_stripe lockless" changes the order stripes are released. Originally I thought block layer can take care of request merge, but it appears there are still some requests not merged. It's easy to fix the order. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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773ca82f |
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27-Aug-2013 |
Shaohua Li <shli@kernel.org> |
raid5: make release_stripe lockless release_stripe still has big lock contention. We just add the stripe to a llist without taking device_lock. We let the raid5d thread to do the real stripe release, which must hold device_lock anyway. In this way, release_stripe doesn't hold any locks. The side effect is the released stripes order is changed. But sounds not a big deal, stripes are never handled in order. And I thought block layer can already do nice request merge, which means order isn't that important. I kept the unplug release batch, which is unnecessary with this patch from lock contention avoid point of view, and actually if we delete it, the stripe_head release_list and lru can share storage. But the unplug release batch is also helpful for request merge. We probably can delay wakeup raid5d till unplug, but I'm still afraid of the case which raid5d is running. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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f94c0b66 |
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21-Jul-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: fix interaction of 'replace' and 'recovery'. If a device in a RAID4/5/6 is being replaced while another is being recovered, then the writes to the replacement device currently don't happen, resulting in corruption when the replacement completes and the new drive takes over. This is because the replacement writes are only triggered when 's.replacing' is set and not when the similar 's.sync' is set (which is the case during resync and recovery - it means all devices need to be read). So schedule those writes when s.replacing is set as well. In this case we cannot use "STRIPE_INSYNC" to record that the replacement has happened as that is needed for recording that any parity calculation is complete. So introduce STRIPE_REPLACED to record if the replacement has happened. For safety we should also check that STRIPE_COMPUTE_RUN is not set. This has a similar effect to the "s.locked == 0" test. The latter ensure that now IO has been flagged but not started. The former checks if any parity calculation has been flagged by not started. We must wait for both of these to complete before triggering the 'replace'. Add a similar test to the subsequent check for "are we finished yet". This possibly isn't needed (is subsumed in the STRIPE_INSYNC test), but it makes it more obvious that the REPLACE will happen before we think we are finished. Finally if a NeedReplace device is not UPTODATE then that is an error. We really must trigger a warning. This bug was introduced in commit 9a3e1101b827a59ac9036a672f5fa8d5279d0fe2 (md/raid5: detect and handle replacements during recovery.) which introduced replacement for raid5. That was in 3.3-rc3, so any stable kernel since then would benefit from this fix. Cc: stable@vger.kernel.org (3.3+) Reported-by: qindehua <13691222965@163.com> Tested-by: qindehua <qindehua@163.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
fdcfbbb6 |
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04-Jul-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: allow 5-device RAID6 to be reshaped to 4-device. There is a bug in 'check_reshape' for raid5.c To checks that the new minimum number of devices is large enough (which is good), but it does so also after the reshape has started (bad). This is bad because - the calculation is now wrong as mddev->raid_disks has changed already, and - it is pointless because it is now too late to stop. So only perform that test when reshape has not been committed to. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b29bebd6 |
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01-Jun-2013 |
Jingoo Han <jg1.han@samsung.com> |
md: replace strict_strto*() with kstrto*() The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
5026d7a9 |
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12-Jun-2013 |
H. Peter Anvin <hpa@zytor.com> |
md/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place There are cases where the kernel will believe that the WRITE SAME command is supported by a block device which does not, in fact, support WRITE SAME. This currently happens for SATA drivers behind a SAS controller, but there are probably a hundred other ways that can happen, including drive firmware bugs. After receiving an error for WRITE SAME the block layer will retry the request as a plain write of zeroes, but mdraid will consider the failure as fatal and consider the drive failed. This has the effect that all the mirrors containing a specific set of data are each offlined in very rapid succession resulting in data loss. However, just bouncing the request back up to the block layer isn't ideal either, because the whole initial request-retry sequence should be inside the write bitmap fence, which probably means that md needs to do its own conversion of WRITE SAME to write zero. Until the failure scenario has been sorted out, disable WRITE SAME for raid1, raid5, and raid10. [neilb: added raid5] This patch is appropriate for any -stable since 3.7 when write_same support was added. Cc: stable@vger.kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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4997b72e |
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30-May-2013 |
Kent Overstreet <koverstreet@google.com> |
raid5: Initialize bi_vcnt The patch that converted raid5 to use bio_reset() forgot to initialize bi_vcnt. Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: NeilBrown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Tested-by: Ilia Mirkin <imirkin@alum.mit.edu> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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c0b32972 |
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23-Apr-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: avoid an extra write when writing to a known-bad-block. If we write to a known-bad-block it will be flags as having a ReadError by analyse_stripe, but the write will proceed anyway (as it should). Then the read-error handling will kick in an write again, then re-read. We don't need that 'write-again', so set R5_ReWrite so it looks like it has already been done. Then we will just get the re-read, which we want. Reported-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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6f608040 |
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23-Apr-2013 |
majianpeng <majianpeng@gmail.com> |
md/raid5: Change or of some order to improve efficiency. As the function call is the most expensive of these tests it should be done later in the chain so that it can be avoided in some cases. Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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0a82a8d1 |
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18-Apr-2013 |
Linus Torvalds <torvalds@linux-foundation.org> |
Revert "block: add missing block_bio_complete() tracepoint" This reverts commit 3a366e614d0837d9fc23f78cdb1a1186ebc3387f. Wanlong Gao reports that it causes a kernel panic on his machine several minutes after boot. Reverting it removes the panic. Jens says: "It's not quite clear why that is yet, so I think we should just revert the commit for 3.9 final (which I'm assuming is pretty close). The wifi is crap at the LSF hotel, so sending this email instead of queueing up a revert and pull request." Reported-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Requested-by: Jens Axboe <axboe@kernel.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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2f6db2a7 |
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11-Sep-2012 |
Kent Overstreet <koverstreet@google.com> |
raid5: use bio_reset() Had to shuffle the code around a bit (where bi_rw and bi_end_io were set), but shouldn't really be anything tricky here Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: NeilBrown <neilb@suse.de>
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aa8b57aa |
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05-Feb-2013 |
Kent Overstreet <koverstreet@google.com> |
block: Use bio_sectors() more consistently Bunch of places in the code weren't using it where they could be - this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx into a struct bvec_iter. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: "Ed L. Cashin" <ecashin@coraid.com> CC: Nick Piggin <npiggin@kernel.dk> CC: Jiri Kosina <jkosina@suse.cz> CC: Jim Paris <jim@jtan.com> CC: Geoff Levand <geoff@infradead.org> CC: Alasdair Kergon <agk@redhat.com> CC: dm-devel@redhat.com CC: Neil Brown <neilb@suse.de> CC: Steven Rostedt <rostedt@goodmis.org> Acked-by: Ed Cashin <ecashin@coraid.com>
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f73a1c7d |
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25-Sep-2012 |
Kent Overstreet <koverstreet@google.com> |
block: Add bio_end_sector() Just a little convenience macro - main reason to add it now is preparing for immutable bio vecs, it'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx into a struct bvec_iter. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: Lars Ellenberg <drbd-dev@lists.linbit.com> CC: Jiri Kosina <jkosina@suse.cz> CC: Alasdair Kergon <agk@redhat.com> CC: dm-devel@redhat.com CC: Neil Brown <neilb@suse.de> CC: Martin Schwidefsky <schwidefsky@de.ibm.com> CC: Heiko Carstens <heiko.carstens@de.ibm.com> CC: linux-s390@vger.kernel.org CC: Chris Mason <chris.mason@fusionio.com> CC: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Steven Whitehouse <swhiteho@redhat.com>
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f8dfcffd |
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11-Mar-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: ensure sync and DISCARD don't happen at the same time. A number of problems can occur due to races between resync/recovery and discard. - if sync_request calls handle_stripe() while a discard is happening on the stripe, it might call handle_stripe_clean_event before all of the individual discard requests have completed (so some devices are still locked, but not all). Since commit ca64cae96037de16e4af92678814f5d4bf0c1c65 md/raid5: Make sure we clear R5_Discard when discard is finished. this will cause R5_Discard to be cleared for the parity device, so handle_stripe_clean_event() will not be called when the other devices do become unlocked, so their ->written will not be cleared. This ultimately leads to a WARN_ON in init_stripe and a lock-up. - If handle_stripe_clean_event() does clear R5_UPTODATE at an awkward time for resync, it can lead to s->uptodate being less than disks in handle_parity_checks5(), which triggers a BUG (because it is one). So: - keep R5_Discard on the parity device until all other devices have completed their discard request - make sure we don't try to have a 'discard' and a 'sync' action at the same time. This involves a new stripe flag to we know when a 'discard' is happening, and the use of R5_Overlap on the parity disk so when a discard is wanted while a sync is active, so we know to wake up the discard at the appropriate time. Discard support for RAID5 was added in 3.7, so this is suitable for any -stable kernel since 3.7. Cc: stable@vger.kernel.org (v3.7+) Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com> Tested-by: Jes Sorensen <Jes.Sorensen@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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e3620a3a |
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07-Mar-2013 |
Jonathan Brassow <jbrassow@redhat.com> |
MD RAID5: Avoid accessing gendisk or queue structs when not available MD RAID5: Fix kernel oops when RAID4/5/6 is used via device-mapper Commit a9add5d (v3.8-rc1) added blktrace calls to the RAID4/5/6 driver. However, when device-mapper is used to create RAID4/5/6 arrays, the mddev->gendisk and mddev->queue fields are not setup. Therefore, calling things like trace_block_bio_remap will cause a kernel oops. This patch conditionalizes those calls on whether the proper fields exist to make the calls. (Device-mapper will call trace_block_bio_remap on its own.) This patch is suitable for the 3.8.y stable kernel. Cc: stable@vger.kernel.org (v3.8+) Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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ce7d363a |
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03-Mar-2013 |
NeilBrown <neilb@suse.de> |
md/raid5: schedule_construction should abort if nothing to do. Since commit 1ed850f356a0a422013846b5291acff08815008b md/raid5: make sure to_read and to_write never go negative. It has been possible for handle_stripe_dirtying to be called when there isn't actually any work to do. It then calls schedule_reconstruction() which will set R5_LOCKED on the parity block(s) even when nothing else is happening. This then causes problems in do_release_stripe(). So add checks to schedule_reconstruction() so that if it doesn't find anything to do, it just aborts. This bug was introduced in v3.7, so the patch is suitable for -stable kernels since then. Cc: stable@vger.kernel.org (v3.7+) Reported-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b67bfe0d |
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27-Feb-2013 |
Sasha Levin <sasha.levin@oracle.com> |
hlist: drop the node parameter from iterators I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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51acbcec |
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27-Feb-2013 |
NeilBrown <neilb@suse.de> |
md: remove CONFIG_MULTICORE_RAID456 This doesn't seem to actually help and we have an alternate multi-threading approach waiting in the wings, so just get rid of this config option and associated code. As a bonus, we remove one use of CONFIG_EXPERIMENTAL Cc: Dan Williams <djbw@fb.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: NeilBrown <neilb@suse.de>
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3a366e61 |
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11-Jan-2013 |
Tejun Heo <tj@kernel.org> |
block: add missing block_bio_complete() tracepoint bio completion didn't kick block_bio_complete TP. Only dm was explicitly triggering the TP on IO completion. This makes block_bio_complete TP useless for tracers which want to know about bios, and all other bio based drivers skip generating blktrace completion events. This patch makes all bio completions via bio_endio() generate block_bio_complete TP. * Explicit trace_block_bio_complete() invocation removed from dm and the trace point is unexported. * @rq dropped from trace_block_bio_complete(). bios may fly around w/o queue associated. Verifying and accessing the assocaited queue belongs to TP probes. * blktrace now gets both request and bio completions. Make it ignore bio completions if request completion path is happening. This makes all bio based drivers generate blktrace completion events properly and makes the block_bio_complete TP actually useful. v2: With this change, block_bio_complete TP could be invoked on sg commands which have bio's with %NULL bi_bdev. Update TP assignment code to check whether bio->bi_bdev is %NULL before dereferencing. Signed-off-by: Tejun Heo <tj@kernel.org> Original-patch-by: Namhyung Kim <namhyung@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Cc: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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a9add5d9 |
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30-Oct-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: add blktrace calls This makes it easier to trace what raid5 is doing. Signed-off-by: NeilBrown <neilb@suse.de>
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749586b7 |
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19-Nov-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: use async_tx_quiesce() instead of open-coding it. handle_stripe_expansion contains: if (tx) { async_tx_ack(tx); dma_wait_for_async_tx(tx); } which is very similar to the body of async_tx_quiesce(), except that the later handles an error from dma_wait_for_async_tx() (admittedly by panicing, but that decision belongs in the dma code, not the md code). So just us async_tx_quiesce(). Acked-by: Dan Williams <djbw@fb.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: NeilBrown <neilb@suse.de>
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eed8c02e |
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30-Nov-2012 |
Lukas Czerner <lczerner@redhat.com> |
wait: add wait_event_lock_irq() interface New wait_event{_interruptible}_lock_irq{_cmd} macros added. This commit moves the private wait_event_lock_irq() macro from MD to regular wait includes, introduces new macro wait_event_lock_irq_cmd() instead of using the old method with omitting cmd parameter which is ugly and makes a use of new macros in the MD. It also introduces the _interruptible_ variant. The use of new interface is when one have a special lock to protect data structures used in the condition, or one also needs to invoke "cmd" before putting it to sleep. All new macros are expected to be called with the lock taken. The lock is released before sleep and is reacquired afterwards. We will leave the macro with the lock held. Note to DM: IMO this should also fix theoretical race on waitqueue while using simultaneously wait_event_lock_irq() and wait_event() because of lack of locking around current state setting and wait queue removal. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Cc: Neil Brown <neilb@suse.de> Cc: David Howells <dhowells@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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ca64cae9 |
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20-Nov-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: Make sure we clear R5_Discard when discard is finished. commit 9e44476851e91c86c98eb92b9bc27fb801f89072 MD: raid5 avoid unnecessary zero page for trim change raid5 to clear R5_Discard when the complete request is handled rather than when submitting the per-device discard request. However it did not clear R5_Discard for the parity device. This means that if the stripe_head was reused before it expired from the cache, the setting would be wrong and a hang would result. Also if the R5_Uptodate bit happens to be set, R5_Discard again won't be cleared. But R5_Uptodate really should be clear at this point. So make sure R5_Discard is cleared in all cases, and clear R5_Uptodate when a 'discard' completes. Signed-off-by: NeilBrown <neilb@suse.de>
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ef5b7c69 |
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21-Nov-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: move resolving of reconstruct_state earlier in stripe_handle. The chunk of code in stripe_handle which responds to a *_result value in reconstruct_state is really the completion of some processing that happened outside of handle_stripe (possibly asynchronously) and so should be one of the first things done in handle_stripe(). After the next patch it will be important that it happens before handle_stripe_clean_event(), as that will clear some dev->flags bit that this code tests. Signed-off-by: NeilBrown <neilb@suse.de>
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4ac6875e |
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18-Nov-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: round discard alignment up to power of 2. blkdev_issue_discard currently assumes that the granularity is a power of 2. So in raid5, round the chosen number up to avoid embarrassment. Cc: Shaohua Li <shli@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de>
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83f0d77a |
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29-Oct-2012 |
Masanari Iida <standby24x7@gmail.com> |
md: Fix typo in drivers/md Correct spelling typo in drivers/md. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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e56108d6 |
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10-Oct-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: be careful not to resize_stripes too big. When a RAID5 is reshaping, conf->raid_disks is increased before mddev->delta_disks becomes zero. This can result in check_reshape calling resize_stripes with a number that is too large. This particularly happens when md_check_recovery calls ->check_reshape(). If we use ->previous_raid_disks, we don't risk this. Signed-off-by: NeilBrown <neilb@suse.de>
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7f7583d4 |
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10-Oct-2012 |
Jianpeng Ma <majianpeng@gmail.com> |
Subject: [PATCH] md:change resync_mismatches to atomic64_t to avoid races Now that multiple threads can handle stripes, it is safer to use an atomic64_t for resync_mismatches, to avoid update races. Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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1ed850f3 |
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10-Oct-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: make sure to_read and to_write never go negative. to_read and to_write are part of the result of analysing a stripe before handling it. Their use is to avoid some loops and tests if the values are known to be zero. Thus it is not a problem if they are a little bit larger than they should be. So decrementing them in handle_failed_stripe serves little value, and due to races it could cause some loops to be skipped incorrectly. So remove those decrements. Reported-by: "Jianpeng Ma" <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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a7854487 |
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10-Oct-2012 |
Alexander Lyakas <alex.bolshoy@gmail.com> |
md: When RAID5 is dirty, force reconstruct-write instead of read-modify-write. Signed-off-by: Alex Lyakas <alex@zadarastorage.com> Suggested-by: Yair Hershko <yair@zadarastorage.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b97390ae |
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10-Oct-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: protect debug message against NULL derefernce. The pr_debug in add_stripe_bio could race with something changing *bip, so it is best to hold the lock until after the pr_debug. Reported-by: "Jianpeng Ma" <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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143c4d05 |
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10-Oct-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: add some missing locking in handle_failed_stripe. We really should hold the stripe_lock while accessing 'toread' else we could race with add_stripe_bio and corrupt a list. Reported-by: "Jianpeng Ma" <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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9e444768 |
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10-Oct-2012 |
Shaohua Li <shli@kernel.org> |
MD: raid5 avoid unnecessary zero page for trim We want to avoid zero discarded dev page, because it's useless for discard. But if we don't zero it, another read/write hit such page in the cache and will get inconsistent data. To avoid zero the page, we don't set R5_UPTODATE flag after construction is done. In this way, discard write request is still issued and finished, but read will not hit the page. If the stripe gets accessed soon, we need reread the stripe, but since the chance is low, the reread isn't a big deal. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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620125f2 |
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10-Oct-2012 |
Shaohua Li <shli@kernel.org> |
MD: raid5 trim support Discard for raid4/5/6 has limitation. If discard request size is small, we do discard for one disk, but we need calculate parity and write parity disk. To correctly calculate parity, zero_after_discard must be guaranteed. Even it's true, we need do discard for one disk but write another disks, which makes the parity disks wear out fast. This doesn't make sense. So an efficient discard for raid4/5/6 should discard all data disks and parity disks, which requires the write pattern to be (A, A+chunk_size, A+chunk_size*2...). If A's size is smaller than chunk_size, such pattern is almost impossible in practice. So in this patch, I only handle the case that A's size equals to chunk_size. That is discard request should be aligned to stripe size and its size is multiple of stripe size. Since we can only handle request with specific alignment and size (or part of the request fitting stripes), we can't guarantee zero_after_discard even zero_after_discard is true in low level drives. The block layer doesn't send down correctly aligned requests even correct discard alignment is set, so I must filter out. For raid4/5/6 parity calculation, if data is 0, parity is 0. So if zero_after_discard is true for all disks, data is consistent after discard. Otherwise, data might be lost. Let's consider a scenario: discard a stripe, write data to one disk and write parity disk. The stripe could be still inconsistent till then depending on using data from other data disks or parity disks to calculate new parity. If the disk is broken, we can't restore it. So in this patch, we only enable discard support if all disks have zero_after_discard. If discard fails in one disk, we face the similar inconsistent issue above. The patch will make discard follow the same path as normal write request. If discard fails, a resync will be scheduled to make the data consistent. This isn't good to have extra writes, but data consistency is important. If a subsequent read/write request hits raid5 cache of a discarded stripe, the discarded dev page should have zero filled, so the data is consistent. This patch will always zero dev page for discarded request stripe. This isn't optimal because discard request doesn't need such payload. Next patch will avoid it. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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4ed8731d |
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10-Oct-2012 |
Shaohua Li <shli@kernel.org> |
MD: change the parameter of md thread Change the thread parameter, so the thread can carry extra info. Next patch will use it. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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cb13ff69 |
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24-Sep-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: add missing spin_lock_init. commit b17459c05000fdbe8d10946570a26510f86ec0f raid5: add a per-stripe lock added a spin_lock to the 'stripe_head' struct. Unfortunately there are two places where this struct is allocated but the spin lock was only initialised in one of them. So add the missing spin_lock_init. Signed-off-by: NeilBrown <neilb@suse.de>
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e5c86471 |
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18-Sep-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: fix calculate of 'degraded' when a replacement becomes active. When a replacement device becomes active, we mark the device that it replaces as 'faulty' so that it can subsequently get removed. However 'calc_degraded' only pays attention to the primary device, not the replacement, so the array appears to become degraded, which is wrong. So teach 'calc_degraded' to consider any replacement if a primary device is faulty. This is suitable for -stable as an incorrect 'degraded' value can confuse md and could lead to data corruption. This is only relevant for 3.3 and later. Cc: stable@vger.kernel.org Reported-by: Robin Hill <robin@robinhill.me.uk> Reported-by: John Drescher <drescherjm@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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a852d7b8 |
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18-Sep-2012 |
NeilBrown <neilb@suse.de> |
Revert "md/raid5: For odirect-write performance, do not set STRIPE_PREREAD_ACTIVE." This reverts commit 895e3c5c58a80bb9e4e05d9ac38b4f30e0f97d80. While this patch seemed like a good idea and did help some workloads, it hurts other workloads. Large sequential O_DIRECT writes were faster, Small random O_DIRECT writes were slower. Other changes (batching RAID5 writes) have improved the sequential writes using a different mechanism, so the net result of this patch is definitely negative. So revert it. Reported-by: Shaohua Li <shli@kernel.org> Tested-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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46a06401 |
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01-Aug-2012 |
Shaohua Li <shli@kernel.org> |
raid5: raid5d handle stripe in batch way Let raid5d handle stripe in batch way to reduce conf->device_lock locking. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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8811b596 |
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01-Aug-2012 |
Shaohua Li <shli@kernel.org> |
raid5: make_request use batch stripe release make_request() does stripe release for every stripe and the stripe usually has count 1, which makes previous release_stripe() optimization not work. In my test, this release_stripe() becomes the heaviest pleace to take conf->device_lock after previous patches applied. Below patch makes stripe release batch. All the stripes will be released in unplug. The STRIPE_ON_UNPLUG_LIST bit is to protect concurrent access stripe lru. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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0021b7bc |
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31-Jul-2012 |
NeilBrown <neilb@suse.de> |
md: remove plug_cnt feature of plugging. This seemed like a good idea at the time, but after further thought I cannot see it making a difference other than very occasionally and testing to try to exercise the case it is most likely to help did not show any performance difference by removing it. So remove the counting of active plugs and allow 'pending writes' to be activated at any time, not just when no plugs are active. This is only relevant when there is a write-intent bitmap, and the updating of the bitmap will likely introduce enough delay that the single-threading of bitmap updates will be enough to collect large numbers of updates together. Removing this will make it easier to centralise the unplug code, and will clear the other for other unplug enhancements which have a measurable effect. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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895e3c5c |
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30-Jul-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid5: For odirect-write performance, do not set STRIPE_PREREAD_ACTIVE. 'sync' writes set both REQ_SYNC and REQ_NOIDLE. O_DIRECT writes set REQ_SYNC but not REQ_NOIDLE. We currently assume that a REQ_SYNC request will not be followed by more requests and so set STRIPE_PREREAD_ACTIVE to expedite the request. This is appropriate for sync requests, but not for O_DIRECT requests. So make the setting of STRIPE_PREREAD_ACTIVE conditional on REQ_NOIDLE rather than REQ_SYNC. This is consistent with the documented meaning of REQ_NOIDLE: __REQ_NOIDLE, /* don't anticipate more IO after this one */ Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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3f9e7c14 |
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30-Jul-2012 |
majianpeng <majianpeng@gmail.com> |
raid5: Add R5_ReadNoMerge flag which prevent bio from merging at block layer Because bios will merge at block-layer,so bios-error may caused by other bio which be merged into to the same request. Using this flag,it will find exactly error-sector and not do redundant operation like re-write and re-read. V0->V1:Using REQ_FLUSH instead REQ_NOMERGE avoid bio merging at block layer. Signed-off-by: Jianpeng Ma <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b17459c0 |
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19-Jul-2012 |
Shaohua Li <shli@kernel.org> |
raid5: add a per-stripe lock Add a per-stripe lock to protect stripe specific data. The purpose is to reduce lock contention of conf->device_lock. stripe ->toread, ->towrite are protected by per-stripe lock. Accessing bio list of the stripe is always serialized by this lock, so adding bio to the lists (add_stripe_bio()) and removing bio from the lists (like ops_run_biofill()) not race. If bio in ->read, ->written ... list are not shared by multiple stripes, we don't need any lock to protect ->read, ->written, because STRIPE_ACTIVE will protect them. If the bio are shared, there are two protections: 1. bi_phys_segments acts as a reference count 2. traverse the list uses r5_next_bio, which makes traverse never access bio not belonging to the stripe Let's have an example: | stripe1 | stripe2 | stripe3 | ...bio1......|bio2|bio3|....bio4..... stripe2 has 4 bios, when it's finished, it will decrement bi_phys_segments for all bios, but only end_bio for bio2 and bio3. bio1->bi_next still points to bio2, but this doesn't matter. When stripe1 is finished, it will not touch bio2 because of r5_next_bio check. Next time stripe1 will end_bio for bio1 and stripe3 will end_bio bio4. before add_stripe_bio() addes a bio to a stripe, we already increament the bio bi_phys_segments, so don't worry other stripes release the bio. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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7eaf7e8e |
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19-Jul-2012 |
Shaohua Li <shli@kernel.org> |
raid5: remove unnecessary bitmap write optimization Neil pointed out the bitmap write optimization in handle_stripe_clean_event() is unnecessary, because the chance one stripe gets written twice in the mean time is rare. We can always do a bitmap_startwrite when a write request is added to a stripe and bitmap_endwrite after write request is done. Delete the optimization. With it, we can delete some cases of device_lock. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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e7836bd6 |
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19-Jul-2012 |
Shaohua Li <shli@kernel.org> |
raid5: lockless access raid5 overrided bi_phys_segments Raid5 overrides bio->bi_phys_segments, accessing it is with device_lock hold, which is unnecessary, We can make it lockless actually. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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4eb788df |
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19-Jul-2012 |
Shaohua Li <shli@kernel.org> |
raid5: reduce chance release_stripe() taking device_lock release_stripe() is a place conf->device_lock is heavily contended. We take the lock even stripe count isn't 1, which isn't required. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b357f04a |
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03-Jul-2012 |
NeilBrown <neilb@suse.de> |
md: fix up plugging (again). The value returned by "mddev_check_plug" is only valid until the next 'schedule' as that will unplug things. This could happen at any call to mempool_alloc. So just calling mddev_check_plug at the start doesn't really make sense. So call it just before, or just after, queuing things for the thread. As the action that happens at unplug is to wake the thread, this makes lots of sense. If we cannot add a plug (which requires a small GFP_ATOMIC alloc) we wake thread immediately. RAID5 is a bit different. Requests are queued for the thread and the thread is woken by release_stripe. So we don't need to wake the thread on failure. However the thread doesn't perform certain actions when there is any active plug, so it is important to install a plug before waking the thread. So for RAID5 we install the plug *before* queuing the request and waking the thread. Without this patch it is possible for raid1 or raid10 to queue a request without then waking the thread, resulting in the array locking up. Also change raid10 to only flush_pending_write when there are not active plugs, just like raid1. This patch is suitable for 3.0 or later. I plan to submit it to -stable, but I'll like to let it spend a few weeks in mainline first to be sure it is completely safe. Signed-off-by: NeilBrown <neilb@suse.de>
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fab363b5 |
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02-Jul-2012 |
Shaohua Li <shli@kernel.org> |
raid5: delayed stripe fix There isn't locking setting STRIPE_DELAYED and STRIPE_PREREAD_ACTIVE bits, but the two bits have relationship. A delayed stripe can be moved to hold list only when preread active stripe count is below IO_THRESHOLD. If a stripe has both the bits set, such stripe will be in delayed list and preread count not 0, which will make such stripe never leave delayed list. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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2e8ac303 |
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02-Jul-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid456: When read error cannot be recovered, record bad block We may not be able to fix a bad block if: - the array is degraded - the over-write fails. In these cases we currently eject the device, but we should record a bad block if possible. Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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0232605d |
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02-Jul-2012 |
NeilBrown <neilb@suse.de> |
md: make 'name' arg to md_register_thread non-optional. Having the 'name' arg optional and defaulting to the current personality name is no necessary and leads to errors, as when changing the level of an array we can end up using the name of the old level instead of the new one. So make it non-optional and always explicitly pass the name of the level that the array will be. Reported-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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5f066c63 |
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02-Jul-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: fix refcount problem when blocked_rdev is set. commit 43220aa0f22cd3ce5b30246d50ccd696d119edea md/raid5: fix a hang on device failure. fixed a hang, but introduced a refcounting in-balance so that if the presence of bad-blocks ever caused an rdev to be 'blocked' we would increment the refcount on the rdev and never decrement it. So added the needed rdev_dec_pending when md_wait_for_blocked_rdev is not called. Reported-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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1850753d |
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02-Jul-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid5: In ops_run_io, inc nr_pending before calling md_wait_for_blocked_rdev In ops_run_io(), the call to md_wait_for_blocked_rdev will decrement nr_pending so we lose the reference we hold on the rdev. So atomic_inc it first to maintain the reference. This bug was introduced by commit 73e92e51b7969ef5477d md/raid5. Don't write to known bad block on doubtful devices. which appeared in 3.0, so patch is suitable for stable kernels since then. Cc: stable@vger.kernel.org Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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6c0544e2 |
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11-Jun-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid5: Do not add data_offset before call to is_badblock In chunk_aligned_read() we are adding data_offset before calling is_badblock. But is_badblock also adds data_offset, so that is bad. So move the addition of data_offset to after the call to is_badblock. This bug was introduced by commit 31c176ecdf3563140e639 md/raid5: avoid reading from known bad blocks. which first appeared in 3.0. So that patch is suitable for any -stable kernel from 3.0.y onwards. However it will need minor revision for most of those (as the comment didn't appear until recently). Cc: stable@vger.kernel.org Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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5cfb22a1 |
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02-Jul-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: prefer replacing failed devices over want-replacement devices. If a RAID5 has both a failed device and a device marked as 'WantReplacement', then we should preferentially replace the failed device. However the current code replaces whichever is found first. So split into 2 loops, check fail failed/missing first, and only check for WantReplacement if nothing is failed or missing. Reported-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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da7613b8 |
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21-May-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: improve removal of extra devices after reshape. After a reshape which reduced the number of devices we need to disconnect the extra devices. The code for this doesn't currently handle 'replacement' devices. It is very unlikely that such devices will be present, but it is safest to handle them anyway. So simplify the handling. Just clear In_sync and leave it to remove_and_add_spaces (which will be called soon) to do the real works. Signed-off-by: NeilBrown <neilb@suse.de>
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30b67645 |
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21-May-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: Allow reshape while a bitmap is present. We always should have allowed this. A raid5 reshape doesn't change the size of the bitmap, so not need to restrict it. Also add a test to make sure we don't try to start a reshape on a failed array. Signed-off-by: NeilBrown <neilb@suse.de>
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a4a6125a |
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21-May-2012 |
NeilBrown <neilb@suse.de> |
md: allow array to be resized while bitmap is present. Now that bitmaps can be resized, we can allow an array to be resized while the bitmap is present. This only covers resizing that involves changing the effective size of member devices, not resizing that changes the number of devices. Signed-off-by: NeilBrown <neilb@suse.de>
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bc0934f0 |
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21-May-2012 |
Shaohua Li <shli@kernel.org> |
raid5: support sync request REQ_SYNC is ignored in current raid5 code. Block layer does use it to do policy, for example ioscheduler. This patch adds it. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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cceeca43 |
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21-May-2012 |
Shaohua Li <shli@kernel.org> |
raid5: remove unused variables The two variables are useless. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de>
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b5254dd5 |
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20-May-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: allow for change in data_offset while managing a reshape. The important issue here is incorporating the different in data_offset into calculations concerning when we might need to over-write data that is still thought to be valid. To this end we find the minimum offset difference across all devices and add that where appropriate. Signed-off-by: NeilBrown <neilb@suse.de>
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05616be5 |
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20-May-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: Use correct data_offset for all IO. As there can now be two different data_offsets - an 'old' and a 'new' - we need to carefully choose between them. Signed-off-by: NeilBrown <neilb@suse.de>
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c6563a8c |
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20-May-2012 |
NeilBrown <neilb@suse.de> |
md: add possibility to change data-offset for devices. When reshaping we can avoid costly intermediate backup by changing the 'start' address of the array on the device (if there is enough room). So as a first step, allow such a change to be requested through sysfs, and recorded in v1.x metadata. (As we didn't previous check that all 'pad' fields were zero, we need a new FEATURE flag for this. A (belatedly) check that all remaining 'pad' fields are zero to avoid a repeat of this) The new data offset must be requested separately for each device. This allows each to have a different change in the data offset. This is not likely to be used often but as data_offset can be set per-device, new_data_offset should be too. This patch also removes the 'acknowledged' arg to rdev_set_badblocks as it is never used and never will be. At the same time we add a new arg ('in_new') which is currently always zero but will be used more soon. When a reshape finishes we will need to update the data_offset and rdev->sectors. So provide an exported function to do that. Signed-off-by: NeilBrown <neilb@suse.de>
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2c810cdd |
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20-May-2012 |
NeilBrown <neilb@suse.de> |
md: allow a reshape operation to be reversed. Currently a reshape operation always progresses from the start of the array to the end unless the number of devices is being reduced, in which case it progressed in the opposite direction. To reverse a partial reshape which changes the number of devices you can stop the array and re-assemble with the raid-disks numbers reversed and it will undo. However for a reshape that does not change the number of devices it is not possible to reverse the reshape in the middle - you have to wait until it completes. So add a 'reshape_direction' attribute with is either 'forwards' or 'backwards' and can be explicitly set when delta_disks is zero. This will become more important when we allow the data_offset to change in a reshape. Then the explicit statement of what direction is being used will be more useful. This can be enabled in raid5 trivially as it already supports reverse reshape and just needs to use a different trigger to request it. Signed-off-by: NeilBrown <neilb@suse.de>
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c6d2e084 |
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01-Apr-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid5: Fix a bug about judging if the operation is syncing or replacing When create a raid5 using assume-clean and echo check or repair to sync_action.Then component disks did not operated IO but the raid check/resync faster than normal. Because the judgement in function analyse_stripe(): if (do_recovery || sh->sector >= conf->mddev->recovery_cp) s->syncing = 1; else s->replacing = 1; When check or repair,the recovery_cp == MaxSectore,so syncing equal zero not one. This bug was introduced by commit 9a3e1101b827 md/raid5: detect and handle replacements during recovery. so this patch is suitable for 3.3-stable. Cc: stable@vger.kernel.org Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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18b9837e |
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01-Apr-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: fix handling of bad blocks during recovery. 1/ We can only treat a known-bad-block like a read-error if we have the data that belongs in that block. So fix that test. 2/ If we cannot recovery a stripe due to insufficient data, don't tell "md_done_sync" that the sync failed unless we really did fail something. If we successfully record bad blocks, that is success. Reported-by: "majianpeng" <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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dafb20fa |
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18-Mar-2012 |
NeilBrown <neilb@suse.de> |
md: tidy up rdev_for_each usage. md.h has an 'rdev_for_each()' macro for iterating the rdevs in an mddev. However it uses the 'safe' version of list_for_each_entry, and so requires the extra variable, but doesn't include 'safe' in the name, which is useful documentation. Consequently some places use this safe version without needing it, and many use an explicity list_for_each entry. So: - rename rdev_for_each to rdev_for_each_safe - create a new rdev_for_each which uses the plain list_for_each_entry, - use the 'safe' version only where needed, and convert all other list_for_each_entry calls to use rdev_for_each. Signed-off-by: NeilBrown <neilb@suse.de>
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dc10c643 |
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18-Mar-2012 |
NeilBrown <neilb@suse.de> |
md: allow re-add to failed arrays. When an array is failed (some data inaccessible) then there is no point attempting to add a spare as it could not possibly be recovered. However that may be value in re-adding a recently removed device. e.g. if there is a write-intent-bitmap and it is clear, then access to the data could be restored by this action. So don't reject a re-add to a failed array for RAID10 and RAID5 (the only arrays types that check for a failed array). Signed-off-by: NeilBrown <neilb@suse.de>
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41fe75f6 |
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12-Mar-2012 |
majianpeng <majianpeng@gmail.com> |
md/raid5: use atomic_dec_return() instead of atomic_dec() and atomic_read(). Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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9d4c7d87 |
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12-Mar-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: removed unused 'added_devices' variable. commit 908f4fbd265733 removed the last user of this variable, so we should discard it completely. Signed-off-by: NeilBrown <neilb@suse.de>
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1e3fa9bd |
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12-Mar-2012 |
NeilBrown <neilb@suse.de> |
md/raid5: make sure reshape_position is cleared on error path. Leaving a valid reshape_position value in place could be confusing. Signed-off-by: NeilBrown <neilb@suse.de>
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3a6de292 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Mark device want_replacement when we see a write error. Now that WantReplacement drives are replaced cleanly, mark a drive as WantReplacement when we see a write error. It might get failed soon so the WantReplacement flag is irrelevant, but if the write error is recorded in the bad block log, we still want to activate any spare that might be available. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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7bfec5f3 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: If there is a spare and a want_replacement device, start replacement. When attempting to add a spare to a RAID[456] array, also consider adding it as a replacement for a want_replacement device. This requires that common md code attempt hot_add even when the array is not formally degraded. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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17045f52 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: recognise replacements when assembling array. If a Replacement is seen, file it as such. If we see two replacements (or two normal devices) for the one slot, abort. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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dd054fce |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: handle activation of replacement device when recovery completes. When recovery completes - as reported by a call to ->spare_active, we clear In_sync on the original and set it on the replacement. Then when the original gets removed we move the replacement from 'replacement' to 'rdev'. This could race with other code that is looking at these pointers, so we use memory barriers and careful ordering to ensure that a reader might see one device twice, but never no devices. Then the readers guard against using both devices, which could only happen when writing. Signed-off-by: NeilBrown <neilb@suse.de>
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9a3e1101 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: detect and handle replacements during recovery. During recovery we want to write to the replacement but not the original. So we have two new flags - R5_NeedReplace if this stripe has a replacement that needs to be written at some stage - R5_WantReplace if NeedReplace, and the data is available, and a 'sync' has been requested on this stripe. We also distinguish between 'sync and replace' which need to read all other devices, and 'replace' which only needs to read the devices being replaced. Note that during resync we always write to any replacement device. It might not need to be written to, but as we don't read to compare, we have to write to be sure. Signed-off-by: NeilBrown <neilb@suse.de>
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977df362 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: writes should get directed to replacement as well as original. When writing, we need to submit two writes, one to the original, and one to the replacement - if there is a replacement. If the write to the replacement results in a write error, we just fail the device. We only try to record write errors to the original. When writing for recovery, we shouldn't write to the original. This will be addressed in a subsequent patch that generally addresses recovery. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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657e3e4d |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: allow removal for failed replacement devices. Enhance raid5_remove_disk to be able to remove ->replacement as well as ->rdev. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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14a75d3e |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: preferentially read from replacement device if possible. If a replacement device is present and has been recovered far enough, then use it for reading into the stripe cache. If we get an error we don't try to repair it, we just fail the device. A replacement device that gives errors does not sound sensible. This requires removing the setting of R5_ReadError when we get a read error during a read that bypasses the cache. It was probably a bad idea anyway as we don't know that every block in the read caused an error, and it could cause ReadError to be set for the replacement device, which is bad. Signed-off-by: NeilBrown <neilb@suse.de>
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995c4275 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: remove redundant bio initialisations. We current initialise some fields of a bio when preparing a stripe_head, and again just before submitting the request. Remove the duplication by only setting the fields that lower level devices don't touch in raid5_build_block, and only set the changeable fields in ops_run_io. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
671488cc |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: allow each slot to have an extra replacement device Just enhance data structures to record a second device per slot to be used as a 'replacement' device, replacing the original. We also have a second bio in each slot in each stripe_head. This will only be used when writing to the array - we need to write to both the original and the replacement at the same time, so will need two bios. For now, only try using the replacement drive for aligned-reads. In this case, we prefer the replacement if it has been recovered far enough, otherwise use the original. This includes a small enhancement. Previously we would only do aligned reads if the target device was fully recovered. Now we also do them if it has recovered far enough. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
b8321b68 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md: change hot_remove_disk to take an rdev rather than a number. Soon an array will be able to have multiple devices with the same raid_disk number (an original and a replacement). So removing a device based on the number won't work. So pass the actual device handle instead. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
908f4fbd |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: be more thorough in calculating 'degraded' value. When an array is being reshaped to change the number of devices, the two halves can be differently degraded. e.g. one could be missing a device and the other not. So we need to be more careful about calculating the 'degraded' attribute. Instead of just inc/dec at appropriate times, perform a full re-calculation examining both possible cases. This doesn't happen often so it not a big cost, and we already have most of the code to do it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
30d7a483 |
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22-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: ensure correct assessment of drives during degraded reshape. While reshaping a degraded array (as when reshaping a RAID0 by first converting it to a degraded RAID4) we currently get confused about which devices are in_sync. In most cases we get it right, but in the region that is being reshaped we need to treat non-failed devices as in-sync when we have the data but haven't actually written it out yet. Reported-by: Adam Kwolek <adam.kwolek@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
5d8c71f9 |
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08-Dec-2011 |
Adam Kwolek <adam.kwolek@intel.com> |
md: raid5 crash during degradation NULL pointer access causes crash in raid5 module. Signed-off-by: Adam Kwolek <adam.kwolek@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
9283d8c5 |
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07-Dec-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: never wait for bad-block acks on failed device. Once a device is failed we really want to completely ignore it. It should go away soon anyway. In particular the presence of bad blocks on it should not cause us to block as we won't be trying to write there anyway. So as soon as we can check if a device is Faulty, do so and pretend that it is already gone if it is Faulty. Signed-off-by: NeilBrown <neilb@suse.de>
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#
257a4b42 |
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07-Nov-2011 |
Dan Williams <dan.j.williams@intel.com> |
md/raid5: STRIPE_ACTIVE has lock semantics, add barriers All updates that occur under STRIPE_ACTIVE should be globally visible when STRIPE_ACTIVE clears. test_and_set_bit() implies a barrier, but clear_bit() does not. This is suitable for 3.1-stable. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
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#
9a3f530f |
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07-Nov-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: abort any pending parity operations when array fails. When the number of failed devices exceeds the allowed number we must abort any active parity operations (checks or updates) as they are no longer meaningful, and can lead to a BUG_ON in handle_parity_checks6. This bug was introduce by commit 6c0069c0ae9659e3a91b68eaed06a5c6c37f45c8 in 2.6.29. Reported-by: Manish Katiyar <mkatiyar@gmail.com> Tested-by: Manish Katiyar <mkatiyar@gmail.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
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#
056075c7 |
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03-Jul-2011 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
md: Add module.h to all files using it implicitly A pending cleanup will mean that module.h won't be implicitly everywhere anymore. Make sure the modular drivers in md dir are actually calling out for <module.h> explicitly in advance. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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#
d890fa2b |
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25-Oct-2011 |
NeilBrown <neilb@suse.de> |
md: Fix some bugs in recovery_disabled handling. In 3.0 we changed the way recovery_disabled was handle so that instead of testing against zero, we test an mddev-> value against a conf-> value. Two problems: 1/ one place in raid1 was missed and still sets to '1'. 2/ We didn't explicitly set the conf-> value at array creation time. It defaulted to '0' just like the mddev value does so they could appear equal and thus disable recovery. This did not affect normal 'md' as it calls bind_rdev_to_array which changes the mddev value. However the dmraid interface doesn't call this and so doesn't change ->recovery_disabled; so at array start all recovery is incorrectly disabled. So initialise the 'conf' value to one less that the mddev value, so the will only be the same when explicitly set that way. Reported-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
355840e7 |
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25-Oct-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: fix bug that could result in reads from a failed device. This bug was introduced in 415e72d034c50520ddb7ff79e7d1792c1306f0c9 which was in 2.6.36. There is a small window of time between when a device fails and when it is removed from the array. During this time we might still read from it, but we won't write to it - so it is possible that we could read stale data. We didn't need the test of 'Faulty' before because the test on In_sync is sufficient. Since we started allowing reads from the early part of non-In_sync devices we need a test on Faulty too. This is suitable for any kernel from 2.6.36 onwards, though the patch might need a bit of tweaking in 3.0 and earlier. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
84fc4b56 |
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10-Oct-2011 |
NeilBrown <neilb@suse.de> |
md: rename "mdk_personality" to "md_personality" "mdk" doesn't mean anything any more. Signed-off-by: NeilBrown <neilb@suse.de>
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#
d1688a6d |
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10-Oct-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: typedef removal: raid5_conf_t -> struct r5conf Signed-off-by: NeilBrown <neilb@suse.de>
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#
e373ab10 |
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10-Oct-2011 |
NeilBrown <neilb@suse.de> |
md/raid0: typedef removal: raid0_conf_t -> struct r0conf Signed-off-by: NeilBrown <neilb@suse.de>
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#
fd01b88c |
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10-Oct-2011 |
NeilBrown <neilb@suse.de> |
md: remove typedefs: mddev_t -> struct mddev Having mddev_t and 'struct mddev_s' is ugly and not preferred Signed-off-by: NeilBrown <neilb@suse.de>
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#
3cb03002 |
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10-Oct-2011 |
NeilBrown <neilb@suse.de> |
md: removing typedefs: mdk_rdev_t -> struct md_rdev The typedefs are just annoying. 'mdk' probably refers to 'md_k.h' which used to be an include file that defined this thing. Signed-off-by: NeilBrown <neilb@suse.de>
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#
bdc04e6b |
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06-Oct-2011 |
NeilBrown <neilb@suse.de> |
md: remove some old DEBUGging code. This code is not really helpful and is hard to maintain, so just discard it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
db298e19 |
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06-Oct-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: convert to macros into inline functions. More type-safety. Easier to read. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e4f869d9 |
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06-Oct-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: remove pointless NULL test. In the 'abort' branch of run(), 'conf' cannot possibly be NULL, so remove the test. Reported-by: Zdenek Kabelac <zdenek.kabelac@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
01f96c0a |
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20-Sep-2011 |
NeilBrown <neilb@suse.de> |
md: Avoid waking up a thread after it has been freed. Two related problems: 1/ some error paths call "md_unregister_thread(mddev->thread)" without subsequently clearing ->thread. A subsequent call to mddev_unlock will try to wake the thread, and crash. 2/ Most calls to md_wakeup_thread are protected against the thread disappeared either by: - holding the ->mutex - having an active request, so something else must be keeping the array active. However mddev_unlock calls md_wakeup_thread after dropping the mutex and without any certainty of an active request, so the ->thread could theoretically disappear. So we need a spinlock to provide some protections. So change md_unregister_thread to take a pointer to the thread pointer, and ensure that it always does the required locking, and clears the pointer properly. Reported-by: "Moshe Melnikov" <moshe@zadarastorage.com> Signed-off-by: NeilBrown <neilb@suse.de> cc: stable@kernel.org
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#
5a7bbad2 |
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11-Sep-2011 |
Christoph Hellwig <hch@infradead.org> |
block: remove support for bio remapping from ->make_request There is very little benefit in allowing to let a ->make_request instance update the bios device and sector and loop around it in __generic_make_request when we can archive the same through calling generic_make_request from the driver and letting the loop in generic_make_request handle it. Note that various drivers got the return value from ->make_request and returned non-zero values for errors. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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#
43220aa0 |
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30-Aug-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: fix a hang on device failure. Waiting for a 'blocked' rdev to become unblocked in the raid5d thread cannot work with internal metadata as it is the raid5d thread which will clear the blocked flag. This wasn't a problem in 3.0 and earlier as we only set the blocked flag when external metadata was used then. However we now set it always, so we need to be more careful. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b84db560 |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Clear bad blocks on successful write. On a successful write to a known bad block, flag the sh so that raid5d can remove the known bad block from the list. Signed-off-by: NeilBrown <neilb@suse.de>
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#
73e92e51 |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5. Don't write to known bad block on doubtful devices. If a device has seen write errors, don't write to any known bad blocks on that device. Signed-off-by: NeilBrown <neilb@suse.de>
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#
bc2607f3 |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: write errors should be recorded as bad blocks if possible. When a write error is detected, don't mark the device as failed immediately but rather record the fact for handle_stripe to deal with. Handle_stripe then attempts to record a bad block. Only if that fails does the device get marked as faulty. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7f0da59b |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: use bad-block log to improve handling of uncorrectable read errors. If we get an uncorrectable read error - record a bad block rather than failing the device. And if these errors (which may be due to known bad blocks) cause recovery to be impossible, record a bad block on the recovering devices, or abort the recovery. As we might abort a recovery without failing a device we need to teach RAID5 about recovery_disabled handling. Signed-off-by: NeilBrown <neilb@suse.de>
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#
31c176ec |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: avoid reading from known bad blocks. There are two times that we might read in raid5: 1/ when a read request fits within a chunk on a single working device. In this case, if there is any bad block in the range of the read, we simply fail the cache-bypass read and perform the read though the stripe cache. 2/ when reading into the stripe cache. In this case we mark as failed any device which has a bad block in that strip (1 page wide). Note that we will both avoid reading and avoid writing. This is correct (as we will never read from the block, there is no point writing), but not optimal (as writing could 'fix' the error) - that will be addressed later. If we have not seen any write errors on the device yet, we treat a bad block like a recent read error. This will encourage an attempt to fix the read error which will either generate a write error, or will ensure good data is stored there. We don't yet forget the bad block in that case. That comes later. Now that we honour bad blocks when reading we can allow devices with bad blocks into the array. Signed-off-by: NeilBrown <neilb@suse.de>
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#
de393cde |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md: make it easier to wait for bad blocks to be acknowledged. It is only safe to choose not to write to a bad block if that bad block is safely recorded in metadata - i.e. if it has been 'acknowledged'. If it hasn't we need to wait for the acknowledgement. We support that using rdev->blocked wait and md_wait_for_blocked_rdev by introducing a new device flag 'BlockedBadBlock'. This flag is only advisory. It is cleared whenever we acknowledge a bad block, so that a waiter can re-check the particular bad blocks that it is interested it. It should be set by a caller when they find they need to wait. This (set after test) is inherently racy, but as md_wait_for_blocked_rdev already has a timeout, losing the race will have minimal impact. When we clear "Blocked" was also clear "BlockedBadBlocks" incase it was set incorrectly (see above race). We also modify the way we manage 'Blocked' to fit better with the new handling of 'BlockedBadBlocks' and to make it consistent between externally managed and internally managed metadata. This requires that each raidXd loop checks if the metadata needs to be written and triggers a write (md_check_recovery) if needed. Otherwise a queued write request might cause raidXd to wait for the metadata to write, and only that thread can write it. Before writing metadata, we set FaultRecorded for all devices that are Faulty, then after writing the metadata we clear Blocked for any device for which the Fault was certainly Recorded. The 'faulty' device flag now appears in sysfs if the device is faulty *or* it has unacknowledged bad blocks. So user-space which does not understand bad blocks can continue to function correctly. User space which does, should not assume a device is faulty until it sees the 'faulty' flag, and then sees the list of unacknowledged bad blocks is empty. Signed-off-by: NeilBrown <neilb@suse.de>
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#
34b343cf |
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27-Jul-2011 |
NeilBrown <neilb@suse.de> |
md: don't allow arrays to contain devices with bad blocks. As no personality understand bad block lists yet, we must reject any device that is known to contain bad blocks. As the personalities get taught, these tests can be removed. This only applies to raid1/raid5/raid10. For linear/raid0/multipath/faulty the whole concept of bad blocks doesn't mean anything so there is no point adding the checks. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
8cfa7b0f |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Avoid BUG caused by multiple failures. While preparing to write a stripe we keep the parity block or blocks locked (R5_LOCKED) - towards the end of schedule_reconstruction. If the array is discovered to have failed before this write completes we can leave those blocks LOCKED, and init_stripe will notice that a free stripe still has a locked block and will complain. So clear the R5_LOCKED flag in handle_failed_stripe, and demote the 'BUG' to a 'WARN_ON'. Signed-off-by: NeilBrown <neilb@suse.de>
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#
ddd5115f |
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26-Jul-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: move rdev->corrected_errors counting Read errors are considered to corrected if write-back and re-read cycle is finished without further problems. Thus moving the rdev-> corrected_errors counting after the re-reading looks more reasonable IMHO. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
36fad858 |
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26-Jul-2011 |
Namhyung Kim <namhyung@gmail.com> |
md: introduce link/unlink_rdev() helpers There are places where sysfs links to rdev are handled in a same way. Add the helper functions to consolidate them. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
8bda470e |
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26-Jul-2011 |
Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de> |
md/raid: use printk_ratelimited instead of printk_ratelimit As per printk_ratelimit comment, it should not be used. Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de> Signed-off-by: NeilBrown <neilb@suse.de>
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#
acfe726b |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: finalise new merged handle_stripe. handle_stripe5() and handle_stripe6() are now virtually identical. So discard one and rename the other to 'analyse_stripe()'. It always returns 0, so change it to 'void' and remove the 'done' variable in handle_stripe(). Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
474af965fe |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: move some more common code into handle_stripe The RAID6 version of this code is usable for RAID5 providing: - we test "conf->max_degraded" rather than "2" as appropriate - we make sure s->failed_num[1] is meaningful (and not '-1') when s->failed > 1 The 'return 1' must become 'goto finish' in the new location. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
84789554 |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: move more common code into handle_stripe Apart from 'prexor' which can only be set for RAID5, and 'qd_idx' which can only be meaningful for RAID6, these two chunks of code are nearly the same. So combine them into one adding a test to call either handle_parity_checks5 or handle_parity_checks6 as appropriate. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
c8ac1803 |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: unite handle_stripe_dirtying5 and handle_stripe_dirtying6 RAID6 is only allowed to choose 'reconstruct-write' while RAID5 is also allow 'read-modify-write' Apart from this difference, handle_stripe_dirtying[56] are nearly identical. So resolve these differences and create just one function. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
93b3dbce |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: unite fetch_block5 and fetch_block6 Provided that ->failed_num[1] is not a valid device number (which is easily achieved) fetch_block6 provides all the functionality of fetch_block5. So remove the latter and rename the former to simply "fetch_block". Then handle_stripe_fill5 and handle_stripe_fill6 become the same and can similarly be united. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
5d35e09c |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: rearrange a test in fetch_block6. Next patch will unite fetch_block5 and fetch_block6. First I want to make the differences a little more clear. For RAID6 if we are writing at all and there is a failed device, then we need to load or compute every block so we can do a reconstruct-write. This case isn't needed for RAID5 - we will do a read-modify-write in that case. So make that test a separate test in fetch_block6 rather than merged with two other tests. Make a similar change in fetch_block5 so the one bit that is not needed for RAID6 is clearly separate. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
c5a31000 |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: move more code into common handle_stripe The difference between the RAID5 and RAID6 code here is easily resolved using conf->max_degraded. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
3687c061 |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Move code for finishing a reconstruction into handle_stripe. Prior to commit ab69ae12ceef7 the code in handle_stripe5 and handle_stripe6 to "Finish reconstruct operations initiated by the expansion process" was identical. That commit added an identical stanza of code to each function, but in different places. That was careless. The raid5 code was correct, so move that out into handle_stripe and remove raid6 version. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
86c374ba |
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26-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Remove stripe_head_state arg from handle_stripe_expansion. This arg is only used to differentiate between RAID5 and RAID6 but that is not needed. For RAID5, raid5_compute_sector will set qd_idx to "~0" so j with certainly not equals qd_idx, so there is no need for a guard on that condition. So remove the guard and remove the arg from the declaration and callers of handle_stripe_expansion. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
cc94015a |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: move stripe_head_state and more code into handle_stripe. By defining the 'stripe_head_state' in 'handle_stripe', we can move some common code out of handle_stripe[56]() and into handle_stripe. The means that all accesses for stripe_head_state in handle_stripe[56] need to be 's->' instead of 's.', but the compiler should inline those functions and just use a direct stack reference, and future patches while hoist most of this code up into handle_stripe() so we will revert to "s.". Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
c5709ef6 |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: add some more fields to stripe_head_state Adding these three fields will allow more common code to be moved to handle_stripe() struct field rearrangement by Namhyung Kim. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
f2b3b44d |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: unify stripe_head_state and r6_state 'struct stripe_head_state' stores state about the 'current' stripe that is passed around while handling the stripe. For RAID6 there is an extension structure: r6_state, which is also passed around. There is no value in keeping these separate, so move the fields from the latter into the former. This means that all code now needs to treat s->failed_num as an small array, but this is a small cost. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
82e5a171 |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: move common code into handle_stripe There is common code at the start of handle_stripe5 and handle_stripe6. Move it into handle_stripe. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
c4c1663b |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: replace sh->lock with an 'active' flag. sh->lock is now mainly used to ensure that two threads aren't running in the locked part of handle_stripe[56] at the same time. That can more neatly be achieved with an 'active' flag which we set while running handle_stripe. If we find the flag is set, we simply requeue the stripe for later by setting STRIPE_HANDLE. For safety we take ->device_lock while examining the state of the stripe and creating a summary in 'stripe_head_state / r6_state'. This possibly isn't needed but as shared fields like ->toread, ->towrite are checked it is safer for now at least. We leave the label after the old 'unlock' called "unlock" because it will disappear in a few patches, so renaming seems pointless. This leaves the stripe 'locked' for longer as we clear STRIPE_ACTIVE later, but that is not a problem. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
cbe47ec5 |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Protect some more code with ->device_lock. Other places that change or follow dev->towrite and dev->written take the device_lock as well as the sh->lock. So it should really be held in these places too. Also, doing so will allow sh->lock to be discarded. with merged fixes by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
83206d66 |
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25-Jul-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: Remove use of sh->lock in sync_request This is the start of a series of patches to remove sh->lock. sync_request takes sh->lock before setting STRIPE_SYNCING to ensure there is no race with testing it in handle_stripe[56]. Instead, use a new flag STRIPE_SYNC_REQUESTED and test it early in handle_stripe[56] (after getting the same lock) and perform the same set/clear operations if it was set. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Namhyung Kim <namhyung@gmail.com>
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#
ffd96e35 |
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18-Jul-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: get rid of duplicated call to bio_data_dir() In raid5::make_request(), once bio_data_dir(@bi) is detected it never (and couldn't) be changed. Use the result always. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
6ce32846 |
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18-Jul-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: use kmem_cache_zalloc() Replace kmem_cache_alloc + memset(,0,) to kmem_cache_zalloc. I think it's not harmful since @conf->slab_cache already knows actual size of struct stripe_head. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
fcde9075 |
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13-Jun-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: remove unusual use of bio_iovec_idx() In the bio_for_each_segment loop, bvl always points current bio_vec, so the same as bio_iovec_idx(, i). Let's get rid of it. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
b062962e |
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13-Jun-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: fix FUA request handling in ops_run_io() Commit e9c7469bb4f5 ("md: implment REQ_FLUSH/FUA support") introduced R5_WantFUA flag and set rw to WRITE_FUA in that case. However remaining code still checks whether rw is exactly same as WRITE or not, so FUAed-write ends up with being treated as READ. Fix it. This bug has been present since 2.6.37 and the fix is suitable for any -stable kernel since then. It is not clear why this has not caused more problems. Cc: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
9b2dc8b6 |
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12-Jun-2011 |
Namhyung Kim <namhyung@gmail.com> |
md/raid5: fix raid5_set_bi_hw_segments The @bio->bi_phys_segments consists of active stripes count in the lower 16 bits and processed stripes count in the upper 16 bits. So logical-OR operator should be bitwise one. This bug has been present since 2.6.27 and the fix is suitable for any -stable kernel since then. Fortunately the bad code is only used on error paths and is relatively unlikely to be hit. Cc: stable@kernel.org Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
d6b212f4 |
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08-Jun-2011 |
Jonathan Brassow <jbrassow@redhat.com> |
MD: raid5 do not set fullsync Add check to determine if a device needs full resync or if partial resync will do RAID 5 was assuming that if a device was not In_sync, it must undergo a full resync. We add a check to see if 'saved_raid_disk' is the same as 'raid_disk'. If it is, we can safely skip the full resync and rely on the bitmap for partial recovery instead. This is the legitimate purpose of 'saved_raid_disk', from md.h: int saved_raid_disk; /* role that device used to have in the * array and could again if we did a partial * resync from the bitmap */ Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
b098636c |
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10-May-2011 |
NeilBrown <neilb@suse.de> |
md: allow resync_start to be set while an array is active. The sysfs attribute 'resync_start' (known internally as recovery_cp), records where a resync is up to. A value of 0 means the array is not known to be in-sync at all. A value of MaxSector means the array is believed to be fully in-sync. When the size of member devices of an array (RAID1,RAID4/5/6) is increased, the array can be increased to match. This process sets resync_start to the old end-of-device offset so that the new part of the array gets resynced. However with RAID1 (and RAID6) a resync is not technically necessary and may be undesirable. So it would be good if the implied resync after the array is resized could be avoided. So: change 'resync_start' so the value can be changed while the array is active, and as a precaution only allow it to be changed while resync/recovery is 'frozen'. Changing it once resync has started is not going to be useful anyway. This allows the array to be resized without a resync by: write 'frozen' to 'sync_action' write new size to 'component_size' (this will set resync_start) write 'none' to 'resync_start' write 'idle' to 'sync_action'. Also slightly improve some tests on recovery_cp when resizing raid1/raid5. Now that an arbitrary value could be set we should be more careful in our tests. Signed-off-by: NeilBrown <neilb@suse.de>
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#
6f8d0c77 |
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10-May-2011 |
NeilBrown <neilb@suse.de> |
md: make error_handler functions more uniform and correct. - there is no need to test_bit Faulty, as that was already done in md_error which is the only caller of these functions. - MD_CHANGE_DEVS should be set *after* faulty is set to ensure metadata is updated correctly. - spinlock should be held while updating ->degraded. Signed-off-by: NeilBrown <neilb@suse.de>
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#
aeb878b0 |
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10-Apr-2011 |
Jesper Juhl <jj@chaosbits.net> |
md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course'). There's a small typo in a comment in drivers/md/raid5.c - 'Of course' is misspelled as 'Ofcourse'. This patch fixes the spelling error. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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#
d76c8420 |
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21-Apr-2011 |
Randy Dunlap <randy.dunlap@oracle.com> |
raid5: fix build error, sector_t usage Change <sectors> from unsigned long long to sector_t. This matches its source field. ERROR: "__udivdi3" [drivers/md/raid456.ko] undefined! Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
3b71bd93 |
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19-Apr-2011 |
NeilBrown <neilb@suse.de> |
md: Fix dev_sectors on takeover from raid0 to raid4/5 A raid0 array doesn't set 'dev_sectors' as each device might contribute a different number of sectors. So when converting to a RAID4 or RAID5 we need to set dev_sectors as they need the number. We have already verified that in fact all devices do contribute the same number of sectors, so use that number. Signed-off-by: NeilBrown <neilb@suse.de>
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#
2b7da309 |
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19-Apr-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: remove setting of ->queue_lock We previously needed to set ->queue_lock to match the raid5 device_lock so we could safely use queue_flag_* operations (e.g. for plugging). which test the ->queue_lock is in fact locked. However that need has completely gone away and is unlikely to come back to remove this now-pointless setting. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7c13edc8 |
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18-Apr-2011 |
NeilBrown <neilb@suse.de> |
md: incorporate new plugging into raid5. In raid5 plugging is used for 2 things: 1/ collecting writes that require a bitmap update 2/ collecting writes in the hope that we can create full stripes - or at least more-full. We now release these different sets of stripes when plug_cnt is zero. Also in make_request, we call mddev_check_plug to hopefully increase plug_cnt, and wake up the thread at the end if plugging wasn't achieved for some reason. Signed-off-by: NeilBrown <neilb@suse.de>
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#
482c0834 |
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18-Apr-2011 |
NeilBrown <neilb@suse.de> |
md - remove old plugging code. md has some plugging infrastructure for RAID5 to use because the normal plugging infrastructure required a 'request_queue', and when called from dm, RAID5 doesn't have one of those available. This relied on the ->unplug_fn callback which doesn't exist any more. So remove all of that code, both in md and raid5. Subsequent patches with restore the plugging functionality. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e1dfa0a2 |
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18-Apr-2011 |
NeilBrown <neilb@suse.de> |
md: use new plugging interface for RAID IO. md/raid submits a lot of IO from the various raid threads. So adding start/finish plug calls to those so that some plugging happens. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7eaceacc |
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10-Mar-2011 |
Jens Axboe <jaxboe@fusionio.com> |
block: remove per-queue plugging Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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#
da9cf505 |
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21-Feb-2011 |
NeilBrown <neilb@suse.de> |
md: avoid spinlock problem in blk_throtl_exit blk_throtl_exit assumes that ->queue_lock still exists, so make sure that it does. To do this, we stop redirecting ->queue_lock to conf->device_lock and leave it pointing where it is initialised - __queue_lock. As the blk_plug functions check the ->queue_lock is held, we now take that spin_lock explicitly around the plug functions. We don't need the locking, just the warning removal. This is needed for any kernel with the blk_throtl code, which is which is 2.6.37 and later. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
50da0840 |
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30-Jan-2011 |
NeilBrown <neilb@suse.de> |
md: don't abort checking spares as soon as one cannot be added. As spares can be added manually before a reshape starts, we need to find them all to mark some of them as in_sync. Previously we would abort looking for spares when we found an unallocated spare what could not be added to the array (implying there was no room for new spares). However already-added spares could be later in the list, so we need to keep searching. Signed-off-by: NeilBrown <neilb@suse.de>
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#
469518a3 |
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30-Jan-2011 |
NeilBrown <neilb@suse.de> |
md: fix the test for finding spares in raid5_start_reshape. As spares can be added to the array before the reshape is started, we need to find and count them when checking there are enough. The array could have been degraded, so we need to check all devices, no just those out side of the range of devices in the array before the reshape. So instead of checking the index, check the In_sync flag as that reliably tells if the device is a spare or this purpose. Signed-off-by: NeilBrown <neilb@suse.de>
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#
87a8dec9 |
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30-Jan-2011 |
NeilBrown <neilb@suse.de> |
md: simplify some 'if' conditionals in raid5_start_reshape. There are two consecutive 'if' statements. if (mddev->delta_disks >= 0) .... if (mddev->delta_disks > 0) The code in the second is equally valid if delta_disks == 0, and these two statements are the only place that 'added_devices' is used. So make them a single if statement, make added_devices a local variable, and re-indent it all. No functional change. Signed-off-by: NeilBrown <neilb@suse.de>
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#
1a940fce |
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13-Jan-2011 |
NeilBrown <neilb@suse.de> |
md/raid5: handle manually-added spares in start_reshape. It is possible to manually add spares to specific slots before starting a reshape. raid5_start_reshape should recognised this possibility and include it in the accounting. Signed-off-by: NeilBrown <neilb@suse.de>
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#
75d3da43 |
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13-Jan-2011 |
NeilBrown <neilb@suse.de> |
md: Don't let implementation detail of curr_resync leak out through sysfs. mddev->curr_resync has artificial values of '1' and '2' which are used by the code which ensures only one resync is happening at a time on any given device. These values are internal and should never be exposed to user-space (except when translated appropriately as in the 'pending' status in /proc/mdstat). Unfortunately they are as ->curr_resync is assigned to ->curr_resync_completed and that value is directly visible through sysfs. So change the assignments to ->curr_resync_completed to get the same valued from elsewhere in a form that doesn't have the magic '1' or '2' values. Signed-off-by: NeilBrown <neilb@suse.de>
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#
43c73ca4 |
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13-Jan-2011 |
Jonathan Brassow <jbrassow@redhat.com> |
md/raid5: use sysfs_notify_dirent_safe to avoid NULL pointer With the module parameter 'start_dirty_degraded' set, raid5_spare_active() previously called sysfs_notify_dirent() with a NULL argument (rdev->sysfs_state) when a rebuild finished. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
067032bc |
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13-Jan-2011 |
Joe Perches <joe@perches.com> |
md: Fix single printks with multiple KERN_<level>s Noticed-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
a167f663 |
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26-Oct-2010 |
NeilBrown <neilb@suse.de> |
md: use separate bio pool for each md device. bio_clone and bio_alloc allocate from a common bio pool. If an md device is stacked with other devices that use this pool, or under something like swap which uses the pool, then the multiple calls on the pool can cause deadlocks. So allocate a local bio pool for each md array and use that rather than the common pool. This pool is used both for regular IO and metadata updates. Signed-off-by: NeilBrown <neilb@suse.de>
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#
57dab0bd |
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18-Oct-2010 |
NeilBrown <neilb@suse.de> |
md: use sector_t in bitmap_get_counter bitmap_get_counter returns the number of sectors covered by the counter in a pass-by-reference variable. In some cases this can be very large, so make it a sector_t for safety. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e9c7469b |
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03-Sep-2010 |
Tejun Heo <tj@kernel.org> |
md: implment REQ_FLUSH/FUA support This patch converts md to support REQ_FLUSH/FUA instead of now deprecated REQ_HARDBARRIER. In the core part (md.c), the following changes are notable. * Unlike REQ_HARDBARRIER, REQ_FLUSH/FUA don't interfere with processing of other requests and thus there is no reason to mark the queue congested while FLUSH/FUA is in progress. * REQ_FLUSH/FUA failures are final and its users don't need retry logic. Retry logic is removed. * Preflush needs to be issued to all member devices but FUA writes can be handled the same way as other writes - their processing can be deferred to request_queue of member devices. md_barrier_request() is renamed to md_flush_request() and simplified accordingly. For linear, raid0 and multipath, the core changes are enough. raid1, 5 and 10 need the following conversions. * raid1: Handling of FLUSH/FUA bio's can simply be deferred to request_queues of member devices. Barrier related logic removed. * raid5: Queue draining logic dropped. FUA bit is propagated through biodrain and stripe resconstruction such that all the updated parts of the stripe are written out with FUA writes if any of the dirtying writes was FUA. preread_active_stripes handling in make_request() is updated as suggested by Neil Brown. * raid10: FUA bit needs to be propagated to write clones. linear, raid0, 1, 5 and 10 tested. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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#
6b965620 |
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17-Aug-2010 |
NeilBrown <neilb@suse.de> |
md: provide appropriate return value for spare_active functions. md_check_recovery expects ->spare_active to return 'true' if any spares were activated, but none of them do, so the consequent change in 'degraded' is not notified through sysfs. So count the number of spares activated, subtract it from 'degraded' just once, and return it. Reported-by: Adrian Drzewiecki <adriand@vmware.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
e6ffbcb6 |
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17-Aug-2010 |
Adrian Drzewiecki <adriand@vmware.com> |
md: Notify sysfs when RAID1/5/10 disk is In_sync. When RAID1 is done syncing disks, it'll update the state of synced rdevs to In_sync. But it neglected to notify sysfs that the attribute changed. So any programs that are waiting for an rdev's state to change will not be woken. (raid5/raid10 added by neilb) Signed-off-by: Adrian Drzewiecki <adriand@vmware.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
7b6d91da |
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07-Aug-2010 |
Christoph Hellwig <hch@lst.de> |
block: unify flags for struct bio and struct request Remove the current bio flags and reuse the request flags for the bio, too. This allows to more easily trace the type of I/O from the filesystem down to the block driver. There were two flags in the bio that were missing in the requests: BIO_RW_UNPLUG and BIO_RW_AHEAD. Also I've renamed two request flags that had a superflous RW in them. Note that the flags are in bio.h despite having the REQ_ name - as blkdev.h includes bio.h that is the only way to go for now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
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#
9f7c2220 |
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25-Jul-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: export raid5 unplugging interface. Also remove remaining accesses to ->queue and ->gendisk when ->queue is NULL (As it is in a DM target). Signed-off-by: NeilBrown <neilb@suse.de>
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#
252ac522 |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/plug: optionally use plugger to unplug an array during resync/recovery. If an array doesn't have a 'queue' then md_do_sync cannot unplug it. In that case it will have a 'plugger', so make that available to the mddev, and use it to unplug the array if needed. Signed-off-by: NeilBrown <neilb@suse.de>
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#
2ac87401 |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: add simple plugging infrastructure. md/raid5 uses the plugging infrastructure provided by the block layer and 'struct request_queue'. However when we plug raid5 under dm there is no request queue so we cannot use that. So create a similar infrastructure that is much lighter weight and use it for raid5. Signed-off-by: NeilBrown <neilb@suse.de>
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#
11d8a6e3 |
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25-Jul-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: export is_congested test the dm module will need this for dm-raid45. Also only access ->queue->backing_dev_info->congested_fn if ->queue actually exists. It won't in a dm target. Signed-off-by: NeilBrown <neilb@suse.de>
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#
4a5add49 |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
raid5: Don't set read-ahead when there is no queue dm-raid456 does not provide a 'queue' for raid5 to use, so we must make raid5 stop depending on the queue. First: read_ahead dm handles read-ahead adjustment fully in userspace, so simply don't do any readahead adjustments if there is no queue. Also re-arrange code slightly so all the accesses to ->queue are together. Finally, move the blk_queue_merge_bvec function into the 'if' as the ->split_io setting in dm-raid456 has the same effect. Signed-off-by: NeilBrown <neilb@suse.de>
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#
f4be6b43 |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: ensure we create a unique name for kmem_cache when mddev has no gendisk We will shortly allow md devices with no gendisk (they are attached to a dm-target instead). That will cause mdname() to return 'mdX'. There is one place where mdname really needs to be unique: when creating the name for a slab cache. So in that case, if there is no gendisk, you the address of the mddev formatted in HEX to provide a unique name. Signed-off-by: NeilBrown <neilb@suse.de>
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#
c41d4ac4 |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: factor out code for changing size of stripe cache. Separate the actual 'change' code from the sysfs interface so that it can eventually be called internally. Signed-off-by: NeilBrown <neilb@suse.de>
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#
00bcb4ac |
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01-Jun-2010 |
NeilBrown <neilb@suse.de> |
md: reduce dependence on sysfs. We will want md devices to live as dm targets where sysfs is not visible. So allow md to not connect to sysfs. Signed-off-by: NeilBrown <neilb@suse.de>
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#
3424bf6a |
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17-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: don't include 'spare' drives when reshaping to fewer devices. There are few situations where it would make any sense to add a spare when reducing the number of devices in an array, but it is conceivable: A 6 drive RAID6 with two missing devices could be reshaped to a 5 drive RAID6, and a spare could become available just in time for the reshape, but not early enough to have been recovered first. 'freezing' recovery can make this easy to do without any races. However doing such a thing is a bad idea. md will not record the partially-recovered state of the 'spare' and when the reshape finished it will think that the spare is still spare. Easiest way to avoid this confusion is to simply disallow it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
2f115882 |
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17-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: add a missing 'continue' in a loop. As the comment says, the tail of this loop only applies to devices that are not fully in sync, so if In_sync was set, we should avoid the rest of the loop. This bug will hardly ever cause an actual problem. The worst it can do is allow an array to be assembled that is dirty and degraded, which is not generally a good idea (without warning the sysadmin first). This will only happen if the array is RAID4 or a RAID5/6 in an intermediate state during a reshape and so has one drive that is all 'parity' - no data - while some other device has failed. This is certainly possible, but not at all common. Signed-off-by: NeilBrown <neilb@suse.de>
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#
415e72d0 |
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17-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: Allow recovered part of partially recovered devices to be in-sync During a recovery of reshape the early part of some devices might be in-sync while the later parts are not. We we know we are looking at an early part it is good to treat that part as in-sync for stripe calculations. This is particularly important for a reshape which suffers device failure. Treating the data as in-sync can mean the difference between data-safety and data-loss. Signed-off-by: NeilBrown <neilb@suse.de>
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#
674806d6 |
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16-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: More careful check for "has array failed". When we are reshaping an array, the device failure combinations that cause us to decide that the array as failed are more subtle. In particular, any 'spare' will be fully in-sync in the section of the array that has already been reshaped, thus failures that affect only that section are less critical. So encode this subtlety in a new function and call it as appropriate. The case that showed this problem was a 4 drive RAID5 to 8 drive RAID6 conversion where the last two devices failed. This resulted in: good good good good incomplete good good failed failed while converting a 5-drive RAID6 to 8 drive RAID5 The incomplete device causes the whole array to look bad, bad as it was actually good for the section that had been converted to 8-drives, all the data was actually safe. Reported-by: Terry Morris <tbmorris@tbmorris.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
70fffd0b |
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16-Jun-2010 |
NeilBrown <neilb@suse.de> |
md: Don't update ->recovery_offset when reshaping an array to fewer devices. When an array is reshaped to have fewer devices, the reshape proceeds from the end of the devices to the beginning. If a device happens to be non-In_sync (which is possible but rare) we would normally update the ->recovery_offset as the reshape progresses. However that would be wrong as the recover_offset records that the early part of the device is in_sync, while in fact it would only be the later part that is in_sync, and in any case the offset number would be measured from the wrong end of the device. Relatedly, if after a reshape a spare is discovered to not be recoverred all the way to the end, not allow spare_active to incorporate it in the array. This becomes relevant in the following sample scenario: A 4 drive RAID5 is converted to a 6 drive RAID6 in a combined operation. The RAID5->RAID6 conversion will cause a 5 drive to be included as a spare, then the 5drive -> 6drive reshape will effectively rebuild that spare as it progresses. The 6th drive is treated as in_sync the whole time as there is never any case that we might consider reading from it, but must not because there is no valid data. If we interrupt this reshape part-way through and reverse it to return to a 5-drive RAID6 (or event a 4-drive RAID5), we don't want to update the recovery_offset - as that would be wrong - and we don't want to include that spare as active in the 5-drive RAID6 when the reversed reshape completed and it will be mostly out-of-sync still. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e4e11e38 |
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16-Jun-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: avoid oops when number of devices is reduced then increased. The entries in the stripe_cache maintained by raid5 are enlarged when we increased the number of devices in the array, but not shrunk when we reduce the number of devices. So if entries are added after reducing the number of devices, we much ensure to initialise the whole entry, not just the part that is currently relevant. Otherwise if we enlarge the array again, we will reference uninitialised values. As grow_buffers/shrink_buffer now want to use a count that is stored explicity in the raid_conf, they should get it from there rather than being passed it as a parameter. Signed-off-by: NeilBrown <neilb@suse.de>
|
#
55af6bb5 |
|
26-May-2010 |
Akinobu Mita <akinobu.mita@gmail.com> |
md: convert cpu notifier to return encapsulate errno value By the previous modification, the cpu notifier can return encapsulate errno value. This converts the cpu notifiers for raid5. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
7b0bb536 |
|
27-Apr-2010 |
Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com> |
md/raid6: Fix raid-6 read-error correction in degraded state Fix: Raid-6 was not trying to correct a read-error when in singly-degraded state and was instead dropping one more device, going to doubly-degraded state. This patch fixes this behaviour. Tested-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com> Reported-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
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#
0c55e022 |
|
02-May-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: improve consistency of error messages. Many 'printk' messages from the raid456 module mention 'raid5' even though it may be a 'raid6' or even 'raid4' array. This can cause confusion. Also the actual array name is not always reported and when it is it is not reported consistently. So change all the messages to start: md/raid:%s: where '%s' becomes e.g. md3 to identify the particular array. Signed-off-by: NeilBrown <neilb@suse.de>
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#
f1b29bca |
|
01-May-2010 |
Dan Williams <dan.j.williams@intel.com> |
md/raid4: permit raid0 takeover For consistency allow raid4 to takeover raid0 in addition to raid5 (with a raid4 layout). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
21a52c6d |
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31-Mar-2010 |
NeilBrown <neilb@suse.de> |
md: pass mddev to make_request functions rather than request_queue We used to pass the personality make_request function direct to the block layer so the first argument had to be a queue. But now we have the intermediary md_make_request so it makes at lot more sense to pass a struct mddev_s. It makes it possible to have an mddev without its own queue too. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b821eaa5 |
|
28-Mar-2010 |
NeilBrown <neilb@suse.de> |
md: remove ->changed and related code. We set ->changed to 1 and call check_disk_change at the end of md_open so that bd_invalidated would be set and thus partition rescan would happen appropriately. Now that we call revalidate_disk directly, which sets bd_invalidates, that indirection is no longer needed and can be removed. Signed-off-by: NeilBrown <neilb@suse.de>
|
#
49077326 |
|
24-Mar-2010 |
NeilBrown <neilb@suse.de> |
md: move io accounting out of personalities into md_make_request While I generally prefer letting personalities do as much as possible, given that we have a central md_make_request anyway we may as well use it to simplify code. Also this centralises knowledge of ->gendisk which will help later. Signed-off-by: NeilBrown <neilb@suse.de>
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#
2b7f2228 |
|
24-Mar-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: small tidyup in raid5_align_endio Diving through ->queue to find mddev is unnecessarily complex - there is an easier path to finding mddev, so use that. Signed-off-by: NeilBrown <neilb@suse.de>
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#
a78d38a1 |
|
21-Mar-2010 |
NeilBrown <neilb@suse.de> |
md: add support for raid5 to raid4 conversion This is unlikely to be wanted, but we may as well provide it for completeness. Signed-off-by: NeilBrown <neilb@suse.de>
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#
54071b38 |
|
07-Mar-2010 |
Trela Maciej <Maciej.Trela@intel.com> |
md:Add support for Raid0->Raid5 takeover Signed-off-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
7b92813c |
|
07-Mar-2010 |
H Hartley Sweeten <hartleys@visionengravers.com> |
drivers/md: Remove unnecessary casts of void * void pointers do not need to be cast to other pointer types. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
a64c876f |
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14-Apr-2010 |
NeilBrown <neilb@suse.de> |
md: manage redundancy group in sysfs when changing level. Some levels expect the 'redundancy group' to be present, others don't. So when we change level of an array we might need to add or remove this group. This requires fixing up the current practice of overloading ->private to indicate (when ->pers == NULL) that something needs to be removed. So create a new ->to_remove to fill that role. When changing levels, we may need to add or remove attributes. When changing RAID5 -> RAID6, we both add and remove the same thing. It is important to catch this and optimise it out as the removal is delayed until a lock is released, so trying to add immediately would cause problems. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
87aa6300 |
|
27-Apr-2010 |
Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com> |
md/raid6: Fix raid-6 read-error correction in degraded state Fix: Raid-6 was not trying to correct a read-error when in singly-degraded state and was instead dropping one more device, going to doubly-degraded state. This patch fixes this behaviour. Tested-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: Gabriele A. Trombetti <g.trombetti.lkrnl1213@logicschema.com> Reported-by: Janos Haar <janos.haar@netcenter.hu> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
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#
6e3b96ed |
|
22-Apr-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: fix previous patch. Previous patch changes stripe and chunk_number to sector_t but mistakenly did not update all of the divisions to use sector_dev(). This patch changes all the those divisions (actually the '%' operator) to sector_div. Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org Tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
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#
35f2a591 |
|
19-Apr-2010 |
NeilBrown <neilb@suse.de> |
md/raid5: allow for more than 2^31 chunks. With many large drives and small chunk sizes it is possible to create a RAID5 with more than 2^31 chunks. Make sure this works. Reported-by: Brett King <king.br@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
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#
5a0e3ad6 |
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24-Mar-2010 |
Tejun Heo <tj@kernel.org> |
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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#
8a78362c |
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25-Feb-2010 |
Martin K. Petersen <martin.petersen@oracle.com> |
block: Consolidate phys_segment and hw_segment limits Except for SCSI no device drivers distinguish between physical and hardware segment limits. Consolidate the two into a single segment limit. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
a29d8b8e |
|
01-Feb-2010 |
Tejun Heo <tj@kernel.org> |
percpu: add __percpu sparse annotations to what's left Add __percpu sparse annotations to places which didn't make it in one of the previous patches. All converions are trivial. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Borislav Petkov <borislav.petkov@amd.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Neil Brown <neilb@suse.de>
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#
ef286f6f |
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08-Feb-2010 |
NeilBrown <neilb@suse.de> |
md: fix some lockdep issues between md and sysfs. ====== This fix is related to http://bugzilla.kernel.org/show_bug.cgi?id=15142 but does not address that exact issue. ====== sysfs does like attributes being removed while they are being accessed (i.e. read or written) and waits for the access to complete. As accessing some md attributes takes the same lock that is held while removing those attributes a deadlock can occur. This patch addresses 3 issues in md that could lead to this deadlock. Two relate to calling flush_scheduled_work while the lock is held. This is probably a bad idea in general and as we use schedule_work to delete various sysfs objects it is particularly bad. In one case flush_scheduled_work is called from md_alloc (called by md_probe) called from do_md_run which holds the lock. This call is only present to ensure that ->gendisk is set. However we can be sure that gendisk is always set (though possibly we couldn't when that code was originally written. This is because do_md_run is called in three different contexts: 1/ from md_ioctl. This requires that md_open has succeeded, and it fails if ->gendisk is not set. 2/ from writing a sysfs attribute. This can only happen if the mddev has been registered in sysfs which happens in md_alloc after ->gendisk has been set. 3/ from autorun_array which is only called by autorun_devices, which checks for ->gendisk to be set before calling autorun_array. So the call to md_probe in do_md_run can be removed, and the check on ->gendisk can also go. In the other case flush_scheduled_work is being called in do_md_stop, purportedly to wait for all md_delayed_delete calls (which delete the component rdevs) to complete. However there really isn't any need to wait for them - they have already been disconnected in all important ways. The third issue is that raid5->stop() removes some attribute names while the lock is held. There is already some infrastructure in place to delay attribute removal until after the lock is released (using schedule_work). So extend that infrastructure to remove the raid5_attrs_group. This does not address all lockdep issues related to the sysfs "s_active" lock. The rest can be address by splitting that lockdep context between symlinks and non-symlinks which hopefully will happen. Signed-off-by: NeilBrown <neilb@suse.de>
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#
9eb07c25 |
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08-Feb-2010 |
NeilBrown <neilb@suse.de> |
md: fix 'degraded' calculation when starting a reshape. This code was written long ago when it was not possible to reshape a degraded array. Now it is so the current level of degraded-ness needs to be taken in to account. Also newly addded devices should only reduce degradedness if they are deemed to be in-sync. In particular, if you convert a RAID5 to a RAID6, and increase the number of devices at the same time, then the 5->6 conversion will make the array degraded so the current code will produce a wrong value for 'degraded' - "-1" to be precise. If the reshape runs to completion end_reshape will calculate a correct new value for 'degraded', but if a device fails during the reshape an incorrect decision might be made based on the incorrect value of "degraded". This patch is suitable for 2.6.32-stable and if they are still open, 2.6.31-stable and 2.6.30-stable as well. Cc: stable@kernel.org Reported-by: Michael Evans <mjevans1983@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
0efb9e61 |
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13-Dec-2009 |
NeilBrown <neilb@suse.de> |
md: add MODULE_DESCRIPTION for all md related modules. Suggested by Oren Held <orenhe@il.ibm.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
729a1866 |
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13-Dec-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: don't complete make_request on barrier until writes are scheduled The post-barrier-flush is sent by md as soon as make_request on the barrier write completes. For raid5, the data might not be in the per-device queues yet. So for barrier requests, wait for any pre-reading to be done so that the request will be in the per-device queues. We use the 'preread_active' count to check that nothing is still in the preread phase, and delay the decrement of this count until after write requests have been submitted to the underlying devices. Signed-off-by: NeilBrown <neilb@suse.de>
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#
a2826aa9 |
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13-Dec-2009 |
NeilBrown <neilb@suse.de> |
md: support barrier requests on all personalities. Previously barriers were only supported on RAID1. This is because other levels requires synchronisation across all devices and so needed a different approach. Here is that approach. When a barrier arrives, we send a zero-length barrier to every active device. When that completes - and if the original request was not empty - we submit the barrier request itself (with the barrier flag cleared) and then submit a fresh load of zero length barriers. The barrier request itself is asynchronous, but any subsequent request will block until the barrier completes. The reason for clearing the barrier flag is that a barrier request is allowed to fail. If we pass a non-empty barrier through a striping raid level it is conceivable that part of it could succeed and part could fail. That would be way too hard to deal with. So if the first run of zero length barriers succeed, we assume all is sufficiently well that we send the request and ignore errors in the second run of barriers. RAID5 needs extra care as write requests may not have been submitted to the underlying devices yet. So we flush the stripe cache before proceeding with the barrier. Note that the second set of zero-length barriers are submitted immediately after the original request is submitted. Thus when a personality finds mddev->barrier to be set during make_request, it should not return from make_request until the corresponding per-device request(s) have been queued. That will be done in later patches. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Andre Noll <maan@systemlinux.org>
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#
8553fe7ec |
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13-Dec-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: remove some sparse warnings. qd_idx is previously declared and given exactly the same value! Signed-off-by: NeilBrown <neilb@suse.de>
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#
c148ffdc |
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12-Nov-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: Allow dirty-degraded arrays to be assembled when only party is degraded. Normally is it not safe to allow a raid5 that is both dirty and degraded to be assembled without explicit request from that admin, as it can cause hidden data corruption. This is because 'dirty' means that the parity cannot be trusted, and 'degraded' means that the parity needs to be used. However, if the device that is missing contains only parity, then there is no issue and assembly can continue. This particularly applies when a RAID5 is being converted to a RAID6 and there is an unclean shutdown while the conversion is happening. So check for whether the degraded space only contains parity, and in that case, allow the assembly. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7ef90146 |
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12-Nov-2009 |
NeilBrown <neilb@suse.de> |
Don't unconditionally set in_sync on newly added device in raid5_reshape When a reshape finds that it can add spare devices into the array, those devices might already be 'in_sync' if they are beyond the old size of the array, or they might not if they are within the array. The first case happens when we change an N-drive RAID5 to an N+1-drive RAID5. The second happens when we convert an N-drive RAID5 to an N+1-drive RAID6. So set the flag more carefully. Also, ->recovery_offset is only meaningful when the flag is clear, so only set it in that case. This change needs the preceding two to ensure that the non-in_sync device doesn't get evicted from the array when it is stopped, in the case where v0.90 metadata is used. Signed-off-by: NeilBrown <neilb@suse.de>
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#
8dee7211 |
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05-Nov-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: make sure curr_sync_completes is uptodate when reshape starts This value is visible through sysfs and is used by mdadm when it manages a reshape (backing up data that is about to be rearranged). So it is important that it is always correct. Current it does not get updated properly when a reshape starts which can cause problems when assembling an array that is in the middle of being reshaped. This is suitable for 2.6.31.y stable kernels. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
6629542e |
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19-Oct-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: kill a gcc-4.0.1 'uninitialized variable' warning Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
5dd33c9a |
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15-Oct-2009 |
NeilBrown <neilb@suse.de> |
md/async: don't pass a memory pointer as a page pointer. md/raid6 passes a list of 'struct page *' to the async_tx routines, which then either DMA map them for offload, or take the page_address for CPU based calculations. For RAID6 we sometime leave 'blanks' in the list of pages. For CPU based calcs, we want to treat theses as a page of zeros. For offloaded calculations, we simply don't pass a page to the hardware. Currently the 'blanks' are encoded as a pointer to raid6_empty_zero_page. This is a 4096 byte memory region, not a 'struct page'. This is mostly handled correctly but is rather ugly. So change the code to pass and expect a NULL pointer for the blanks. When taking page_address of a page, we need to check for a NULL and in that case use raid6_empty_zero_page. Signed-off-by: NeilBrown <neilb@suse.de>
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#
5e5e3e78 |
|
15-Oct-2009 |
NeilBrown <neilb@suse.de> |
md: Fix handling of raid5 array which is being reshaped to fewer devices. When a raid5 (or raid6) array is being reshaped to have fewer devices, conf->raid_disks is the latter and hence smaller number of devices. However sometimes we want to use a number which is the total number of currently required devices - the larger of the 'old' and 'new' sizes. Before we implemented reducing the number of devices, this was always 'new' i.e. ->raid_disks. Now we need max(raid_disks, previous_raid_disks) in those places. This particularly affects assembling an array that was shutdown while in the middle of a reshape to fewer devices. md.c needs a similar fix when interpreting the md metadata. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e4424fee |
|
15-Oct-2009 |
NeilBrown <neilb@suse.de> |
md: fix problems with RAID6 calculations for DDF. Signed-off-by: NeilBrown <neilb@suse.de>
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#
417b8d4a |
|
15-Oct-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid456: downlevel multicore operations to raid_run_ops The percpu conversion allowed a straightforward handoff of stripe processing to the async subsytem that initially showed some modest gains (+4%). However, this model is too simplistic and leads to stripes bouncing between raid5d and the async thread pool for every invocation of handle_stripe(). As reported by Holger this can fall into a pathological situation severely impacting throughput (6x performance loss). By downleveling the parallelism to raid_run_ops the pathological stripe_head bouncing is eliminated. This version still exhibits an average 11% throughput loss for: mdadm --create /dev/md0 /dev/sd[b-q] -n 16 -l 6 echo 1024 > /sys/block/md0/md/stripe_cache_size dd if=/dev/zero of=/dev/md0 bs=1024k count=2048 ...but the results are at least stable and can be used as a base for further multicore experimentation. Reported-by: Holger Kiehl <Holger.Kiehl@dwd.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
f5efd45a |
|
15-Oct-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid5: initialize conf->device_lock earlier Deallocating a raid5_conf_t structure requires taking 'device_lock'. Ensure it is initialized before it is used, i.e. initialize the lock before attempting any further initializations that might fail. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
1442577b |
|
15-Oct-2009 |
NeilBrown <neilb@suse.de> |
Revert "md: do not progress the resync process if the stripe was blocked" This reverts commit df10cfbc4d7ab93260d997df754219d390d62a9d. This patch was based on a misunderstanding and risks introducing a busy-wait loop. So revert it. Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
3fa841d7 |
|
23-Sep-2009 |
NeilBrown <neilb@suse.de> |
md: report device as congested when suspended This should writeback from coming when the device is temporarily suspended. Signed-off-by: NeilBrown <neilb@suse.de>
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#
0da3c619 |
|
23-Sep-2009 |
NeilBrown <neilb@suse.de> |
md: Improve name of threads created by md_register_thread The management thread for raid4,5,6 arrays are all called mdX_raid5, independent of the actual raid level, which is wrong and can be confusion. So change md_register_thread to use the name from the personality unless no alternate name (like 'resync' or 'reshape') is given. This is simpler and more correct. Cc: Jinzc <zhenchengjin@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
a9f326eb |
|
23-Sep-2009 |
NeilBrown <neilb@suse.de> |
md: remove sparse waring "symbol xxx shadows an earlier one" Rename some variable and remove some duplicate definitions to avoid there warnings. None of them are actual errors. Signed-off-by: NeilBrown <neilb@suse.de>
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#
6c910a78 |
|
16-Sep-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: cleanup ops_run_compute6_2 Neil says: "It is correct as it stands, but the fact that every branch in the 'if' part ends with a 'return' isn't immediately obvious, so it is clearer if we are explicit about the if / then / else structure." Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
2d6e4ecc |
|
16-Sep-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: eliminate BUG_ON with side effect As pointed out by Neil it should be possible to build a driver with all BUG_ON statements deleted. It's bad form to have a BUG_ON with a side effect. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
1f98a13f |
|
11-Sep-2009 |
Jens Axboe <jens.axboe@oracle.com> |
bio: first step in sanitizing the bio->bi_rw flag testing Get rid of any functions that test for these bits and make callers use bio_rw_flagged() directly. Then it is at least directly apparent what variable and flag they check. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
0403e382 |
|
08-Sep-2009 |
Dan Williams <dan.j.williams@intel.com> |
dmaengine: add fence support Some engines optimize operation by reading ahead in the descriptor chain such that descriptor2 may start execution before descriptor1 completes. If descriptor2 depends on the result from descriptor1 then a fence is required (on descriptor2) to disable this optimization. The async_tx api could implicitly identify dependencies via the 'depend_tx' parameter, but that would constrain cases where the dependency chain only specifies a completion order rather than a data dependency. So, provide an ASYNC_TX_FENCE to explicitly identify data dependencies. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
07a3b417 |
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29-Aug-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid456: distribute raid processing over multiple cores Now that the resources to handle stripe_head operations are allocated percpu it is possible for raid5d to distribute stripe handling over multiple cores. This conversion also adds a call to cond_resched() in the non-multicore case to prevent one core from getting monopolized for raid operations. Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
b774ef49 |
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29-Aug-2009 |
Yuri Tikhonov <yur@emcraft.com> |
md/raid6: remove synchronous infrastructure These routines have been replaced by there asynchronous counterparts. Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
6c0069c0 |
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29-Aug-2009 |
Yuri Tikhonov <yur@emcraft.com> |
md/raid6: asynchronous handle_stripe6 1/ Use STRIPE_OP_BIOFILL to offload completion of read requests to raid_run_ops 2/ Implement a handler for sh->reconstruct_state similar to the raid5 case (adds handling of Q parity) 3/ Prevent handle_parity_checks6 from running concurrently with 'compute' operations 4/ Hook up raid_run_ops Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
d82dfee0 |
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14-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: asynchronous handle_parity_check6 [ Based on an original patch by Yuri Tikhonov ] Implement the state machine for handling the RAID-6 parities check and repair functionality. Note that the raid6 case does not need to check for new failures, like raid5, as it will always writeback the correct disks. The raid5 case can be updated to check zero_sum_result to avoid getting confused by new failures rather than retrying the entire check operation. Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
a9b39a74 |
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29-Aug-2009 |
Yuri Tikhonov <yur@emcraft.com> |
md/raid6: asynchronous handle_stripe_dirtying6 In the synchronous implementation of stripe dirtying we processed a degraded stripe with one call to handle_stripe_dirtying6(). I.e. compute the missing blocks from the other drives, then copy in the new data and reconstruct the parities. In the asynchronous case we do not perform stripe operations directly. Instead, operations are scheduled with flags to be later serviced by raid_run_ops. So, for the degraded case the final reconstruction step can only be carried out after all blocks have been brought up to date by being read, or computed. Like the raid5 case schedule_reconstruction() sets STRIPE_OP_RECONSTRUCT to request a parity generation pass and through operation chaining can handle compute and reconstruct in a single raid_run_ops pass. [dan.j.williams@intel.com: fixup handle_stripe_dirtying6 gating] Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
5599becc |
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29-Aug-2009 |
Yuri Tikhonov <yur@emcraft.com> |
md/raid6: asynchronous handle_stripe_fill6 Modify handle_stripe_fill6 to work asynchronously by introducing fetch_block6 as the raid6 analog of fetch_block5 (schedule compute operations for missing/out-of-sync disks). [dan.j.williams@intel.com: compute D+Q in one pass] Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
c0f7bddb |
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29-Aug-2009 |
Yuri Tikhonov <yur@emcraft.com> |
md/raid5,6: common schedule_reconstruction for raid5/6 Extend schedule_reconstruction5 for reuse by the raid6 path. Add support for generating Q and BUG() if a request is made to perform 'prexor'. Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
ac6b53b6 |
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14-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: asynchronous raid6 operations [ Based on an original patch by Yuri Tikhonov ] The raid_run_ops routine uses the asynchronous offload api and the stripe_operations member of a stripe_head to carry out xor+pq+copy operations asynchronously, outside the lock. The operations performed by RAID-6 are the same as in the RAID-5 case except for no support of STRIPE_OP_PREXOR operations. All the others are supported: STRIPE_OP_BIOFILL - copy data into request buffers to satisfy a read request STRIPE_OP_COMPUTE_BLK - generate missing blocks (1 or 2) in the cache from the other blocks STRIPE_OP_BIODRAIN - copy data out of request buffers to satisfy a write request STRIPE_OP_RECONSTRUCT - recalculate parity for new data that has entered the cache STRIPE_OP_CHECK - verify that the parity is correct The flow is the same as in the RAID-5 case, and reuses some routines, namely: 1/ ops_complete_postxor (renamed to ops_complete_reconstruct) 2/ ops_complete_compute (updated to set up to 2 targets uptodate) 3/ ops_run_check (renamed to ops_run_check_p for xor parity checks) [neilb@suse.de: fixes to get it to pass mdadm regression suite] Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
4e7d2c0a |
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29-Aug-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid5: factor out mark_uptodate from ops_complete_compute5 ops_complete_compute5 can be reused in the raid6 path if it is updated to generically handle a second target. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
ad283ea4 |
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29-Aug-2009 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: add sum check flags Replace the flat zero_sum_result with a collection of flags to contain the P (xor) zero-sum result, and the soon to be utilized Q (raid6 reed solomon syndrome) zero-sum result. Use the SUM_CHECK_ namespace instead of DMA_ since these flags will be used on non-dma-zero-sum enabled platforms. Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
d6f38f31 |
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14-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid5,6: add percpu scribble region for buffer lists Use percpu memory rather than stack for storing the buffer lists used in parity calculations. Include space for dma address conversions and pass that to async_tx via the async_submit_ctl.scribble pointer. [ Impact: move memory pressure from stack to heap ] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
36d1c647 |
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14-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: move the spare page to a percpu allocation In preparation for asynchronous handling of raid6 operations move the spare page to a percpu allocation to allow multiple simultaneous synchronous raid6 recovery operations. Make this allocation cpu hotplug aware to maximize allocation efficiency. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
1a67dde0 |
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12-Aug-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: Properly remove excess drives after shrinking a raid5/6 We were removing the drives, from the array, but not removing symlinks from /sys/.... and not marking the device as having been removed. Signed-off-by: NeilBrown <neilb@suse.de>
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#
a639755c |
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12-Aug-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: make sure a reshape restarts at the correct address. This "if" don't allow for the possibility that the number of devices doesn't change, and so sector_nr isn't set correctly in that case. So change '>' to '>='. Signed-off-by: NeilBrown <neilb@suse.de>
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#
67ac6011 |
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12-Aug-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: allow new reshape modes to be restarted in the middle. md/raid5 doesn't allow a reshape to restart if it involves writing over the same part of disk that it would be reading from. This happens at the beginning of a reshape that increases the number of devices, at the end of a reshape that decreases the number of devices, and continuously for a reshape that does not change the number of devices. The current code is correct for the "increase number of devices" case as the critical section at the start is handled by userspace performing a backup. It does not work for reducing the number of devices, or the no-change case. For 'reducing', we need to invert the test. For no-change we cannot really be sure things will be safe, so simply require the array to be read-only, which is how the user-space code which carefully starts such arrays works. Signed-off-by: NeilBrown <neilb@suse.de>
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#
449aad3e |
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02-Aug-2009 |
NeilBrown <neilb@suse.de> |
md: Use revalidate_disk to effect changes in size of device. As revalidate_disk calls check_disk_size_change, it will cause any capacity change of a gendisk to be propagated to the blockdev inode. So use that instead of mucking about with locks and i_size_write. Also add a call to revalidate_disk in do_md_run and a few other places where the gendisk capacity is changed. Signed-off-by: NeilBrown <neilb@suse.de>
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#
64bd660b |
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02-Aug-2009 |
NeilBrown <neilb@suse.de> |
md: allow raid5_quiesce to work properly when reshape is happening. The ->quiesce method is not supposed to stop resync/recovery/reshape, just normal IO. But in raid5 we don't have a way to know which stripes are being used for normal IO and which for resync etc, so we need to wait for all stripes to be idle to be sure that all writes have completed. However reshape keeps at least some stripe busy for an extended period of time, so a call to raid5_quiesce can block for several seconds needlessly. So arrange for reshape etc to pause briefly while raid5_quiesce is trying to quiesce the array so that the active_stripes count can drop to zero. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e516402c |
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02-Aug-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: set reshape_position correctly when reshape starts. As the internal reshape_progress counter is the main driver for reshape, the fact that reshape_position sometimes starts with the wrong value has minimal effect. It is visible in sysfs and that is all. Signed-off-by: NeilBrown <neilb@suse.de>
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#
95fc17aa |
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30-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: release spare page at ->stop() Add missing call to safe_put_page from stop() by unifying open coded raid5_conf_t de-allocation under free_conf(). Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
a11034b4 |
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14-Jul-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: release spare page at ->stop() Add missing call to safe_put_page from stop() by unifying open coded raid5_conf_t de-allocation under free_conf(). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
e62e58a5 |
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30-Jun-2009 |
NeilBrown <neilb@suse.de> |
md: use interruptible wait when duration is controlled by userspace. User space can set various limits on an md array so that resync waits when it gets to a certain point, or so that I/O is blocked for a short while. When md is waiting against one of these limit, it should use an interruptible wait so as not to add to the load average, and so are not to trigger a warning if the wait goes on for too long. Signed-off-by: NeilBrown <neilb@suse.de>
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#
a5c308d4 |
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30-Jun-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: suspend shouldn't affect read requests. md allows write to regions on an array to be suspended temporarily. This allows user-space to participate is aspects of reshape. In particular, data can be copied with not risk of a race. We should not be blocking read requests though, so don't. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
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#
8f6c2e4b |
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30-Jun-2009 |
Martin K. Petersen <martin.petersen@oracle.com> |
md: Use new topology calls to indicate alignment and I/O sizes Switch MD over to the new disk_stack_limits() function which checks for aligment and adjusts preferred I/O sizes when stacking. Also indicate preferred I/O sizes where applicable. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
48606a9f |
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17-Jun-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: correctly update sync_completed when we reach max_resync At the end of reshape_request we update cyrr_resync_completed if we are about to pause due to reaching resync_max. However we update it to the wrong value. We need to add the "reshape_sectors" that have just been reshaped. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7a3ab908 |
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16-Jun-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid5: add missing call to schedule() after prepare_to_wait() In the unlikely event that reshape progresses past the current request while it is waiting for a stripe we need to schedule() before retrying for 2 reasons: 1/ Prevent list corruption from duplicated list_add() calls without intervening list_del(). 2/ Give the reshape code a chance to make some progress to resolve the conflict. Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
8c6ac868 |
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17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md: Push down reconstruction log message to personality code. Currently, the md layer checks in analyze_sbs() if the raid level supports reconstruction (mddev->level >= 1) and if reconstruction is in progress (mddev->recovery_cp != MaxSector). Move that printk into the personality code of those raid levels that care (levels 1, 4, 5, 6, 10). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
50ac168a |
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17-Jun-2009 |
NeilBrown <neilb@suse.de> |
md: merge reconfig and check_reshape methods. The difference between these two methods is artificial. Both check that a pending reshape is valid, and perform any aspect of it that can be done immediately. 'reconfig' handles chunk size and layout. 'check_reshape' handles raid_disks. So make them just one method. Signed-off-by: NeilBrown <neilb@suse.de>
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#
597a711b |
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17-Jun-2009 |
NeilBrown <neilb@suse.de> |
md: remove unnecessary arguments from ->reconfig method. Passing the new layout and chunksize as args is not necessary as the mddev has fields for new_check and new_layout. This is preparation for combining the check_reshape and reconfig methods Signed-off-by: NeilBrown <neilb@suse.de>
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#
01ee22b4 |
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17-Jun-2009 |
NeilBrown <neilb@suse.de> |
md: raid5: check stripe cache is large enough in start_reshape In reshape cases that do not change the number of devices, start_reshape is called without first calling check_reshape. Currently, the check that the stripe_cache is large enough is only done in check_reshape. It should be in start_reshape too. Signed-off-by: NeilBrown <neilb@suse.de>
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#
cdc2ae6d |
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17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md: fix some comments. 1/ Raid5 has learned to take over also raid4 and raid6 arrays. 2/ new_chunk in mdp_superblock_1 is in sectors, not bytes. Signed-off-by: NeilBrown <neilb@suse.de>
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#
0ba459d2 |
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17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md/raid5: Use is_power_of_2() in raid5_reconfig()/raid6_reconfig(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
09c9e5fa |
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17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md: convert conf->chunk_size and conf->prev_chunk to sectors. This kills some more shifts. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
664e7c41 |
|
17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md: Convert mddev->new_chunk to sectors. A straight-forward conversion which gets rid of some multiplications/divisions/shifts. The patch also introduces a couple of new ones, most of which are due to conf->chunk_size still being represented in bytes. This will be cleaned up in subsequent patches. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
9d8f0363 |
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17-Jun-2009 |
Andre Noll <maan@systemlinux.org> |
md: Make mddev->chunk_size sector-based. This patch renames the chunk_size field to chunk_sectors with the implied change of semantics. Since is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9) = is_power_of_2(chunk_sectors) these bits don't need an adjustment for the shift. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
740da449 |
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16-Jun-2009 |
raz ben yehuda <raziebe@gmail.com> |
md: raid5: chunk size check in setup_conf have raid5 check chunk size in run/reshape method instead of in md Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
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#
070ec55d |
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16-Jun-2009 |
NeilBrown <neilb@suse.de> |
md: remove mddev_to_conf "helper" macro Having a macro just to cast a void* isn't really helpful. I would must rather see that we are simply de-referencing ->private, than have to know what the macro does. So open code the macro everywhere and remove the pointless cast. Signed-off-by: NeilBrown <neilb@suse.de>
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#
0e6e0271 |
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09-Jun-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: fix bug in reshape code when chunk_size decreases. Now that we support changing the chunksize, we calculate "reshape_sectors" to be the max of number of sectors in old and new chunk size. However there is one please where we still use 'chunksize' rather than 'reshape_sectors'. This causes a reshape that reduces the size of chunks to freeze. Signed-off-by: NeilBrown <neilb@suse.de>
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#
a8c906ca |
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08-Jun-2009 |
NeilBrown <neilb@suse.de> |
md/raid5 - avoid deadlocks in get_active_stripe during reshape md has functionality to 'quiesce' and array so that all pending IO completed and no new IO starts. This is used to achieve a stable state before making internal changes. Currently this quiescing applies equally to normal IO, resync IO, and reshape IO. However there is a problem with applying it to reshape IO. Reshape can have multiple 'stripe_heads' that must be active together. If the quiesce come between allocating the first and the last of such a collection, then we deadlock, as the last will not be allocated until the quiesce is lifted, the quiesce will not be lifted until the first (which has been allocated) gets used, and that first cannot be used until the last is allocated. It is not necessary to inhibit reshape IO when a quiesce is requested. Those places in the code that require a full quiesce will ensure the reshape thread is not running at all. So allow reshape requests to get access to new stripe_heads without being blocked by a 'quiesce'. This only affects in-place reshapes (i.e. where the array does not grow or shrink) and these are only newly supported. So this patch is not needed in earlier kernels. Signed-off-by: NeilBrown <neilb@suse.de>
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#
f001a70c |
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08-Jun-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: use conf->raid_disks in preference to mddev->raid_disk mddev->raid_disks can be changed and any time by a request from user-space. It is a suggestion as to what number of raid_disks is desired. conf->raid_disks can only be changed by the raid5 module with suitable locks in place. It is a statement as to the current number of raid_disks. There are two places where the latter should be used, but the former is used. This can lead to a crash when reshaping an array. This patch changes to mddev-> to conf-> Signed-off-by: NeilBrown <neilb@suse.de>
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#
a08abd8c |
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03-Jun-2009 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: structify submission arguments, add scribble Prepare the api for the arrival of a new parameter, 'scribble'. This will allow callers to identify scratchpad memory for dma address or page address conversions. As this adds yet another parameter, take this opportunity to convert the common submission parameters (flags, dependency, callback, and callback argument) into an object that is passed by reference. Also, take this opportunity to fix up the kerneldoc and add notes about the relevant ASYNC_TX_* flags for each routine. [ Impact: moves api pass-by-value parameters to a pass-by-reference struct ] Signed-off-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
88ba2aa5 |
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09-Apr-2009 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: kill ASYNC_TX_DEP_ACK flag In support of inter-channel chaining async_tx utilizes an ack flag to gate whether a dependent operation can be chained to another. While the flag is not set the chain can be considered open for appending. Setting the ack flag closes the chain and flags the descriptor for garbage collection. The ASYNC_TX_DEP_ACK flag essentially means "close the chain after adding this dependency". Since each operation can only have one child the api now implicitly sets the ack flag at dependency submission time. This removes an unnecessary management burden from clients of the api. [ Impact: clean up and enforce one dependency per operation ] Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
ed37d83e |
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27-May-2009 |
NeilBrown <neilb@suse.de> |
md: raid5: change incorrect usage of 'min' macro to 'min_t' A recent patch to raid5.c use min on an int and a sector_t. This isn't allowed. So change it to min_t(sector_t,x,y). Signed-off-by: NeilBrown <neilb@suse.de>
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#
848b3182 |
|
25-May-2009 |
NeilBrown <neilb@suse.de> |
md: raid5: avoid sector values going negative when testing reshape progress. As sector_t in unsigned, we cannot afford to let 'safepos' etc go negative. So replace a -= b; by a -= min(b,a); Signed-off-by: NeilBrown <neilb@suse.de>
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#
ae03bf63 |
|
22-May-2009 |
Martin K. Petersen <martin.petersen@oracle.com> |
block: Use accessor functions for queue limits Convert all external users of queue limits to using wrapper functions instead of poking the request queue variables directly. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
|
#
c03f6a19 |
|
16-Apr-2009 |
NeilBrown <neilb@suse.de> |
md: update sync_completed and reshape_position even more often. There are circumstances when a user-space process might need to "oversee" a resync/reshape process. For example when doing an in-place reshape of a raid5, it is prudent to take a backup of each section before reshaping it as this is the only way to provide safety against an unplanned shutdown (i.e. crash/power failure). The sync_max sysfs value can be used to stop the resync from advancing beyond a particular point. So user-space can: suspend IO to the first section and back it up set 'sync_max' to the end of the section wait for 'sync_completed' to reach that point resume IO on the first section and move on to the next section. However this process requires the kernel and user-space to run in lock-step which could introduce unnecessary delays. It would be better if a 'double buffered' approach could be used with userspace and kernel space working on different sections with the 'next' section always ready when the 'current' section is finished. One problem with implementing this is that sync_completed is only guaranteed to be updated when the sync process reaches sync_max. (it is updated on a time basis at other times, but it is hard to rely on that). This defeats some of the double buffering. With this patch, sync_completed (and reshape_position) get updated as the current position approaches sync_max, so there is room for userspace to advance sync_max early without losing updates. To be precise, sync_completed is updated when the current sync position reaches half way between the current value of sync_completed and the value of sync_max. This will usually be a good time for user space to update sync_max. If sync_max does not get updated, the updates to sync_completed (together with associated metadata updates) will occur at an exponentially increasing frequency which will get unreasonably fast (one update every page) immediately before the process hits sync_max and stops. So the update rate will be unreasonably fast only for an insignificant period of time. Signed-off-by: NeilBrown <neilb@suse.de>
|
#
acb180b0 |
|
14-Apr-2009 |
NeilBrown <neilb@suse.de> |
md: improve usefulness and accuracy of sysfs file md/sync_completed. The sync_completed file reports how much of a resync (or recovery or reshape) has been completed. However due to the possibility of out-of-order completion of writes, it is not certain to be accurate. We have an internal value - mddev->curr_resync_completed - which is an accurate value (though it might not always be quite so uptodate). So: - make curr_resync_completed be uptodate a little more often, particularly when raid5 reshape updates status in the metadata - report curr_resync_completed in the sysfs file - allow poll/select to report all updates to md/sync_completed. This makes sync_completed completed usable by any external metadata handler that wants to record this status information in its metadata. Signed-off-by: NeilBrown <neilb@suse.de>
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#
099f53cb |
|
08-Apr-2009 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: rename zero_sum to val 'zero_sum' does not properly describe the operation of generating parity and checking that it validates against an existing buffer. Change the name of the operation to 'val' (for 'validate'). This is in anticipation of the p+q case where it is a requirement to identify the target parity buffers separately from the source buffers, because the target parity buffers will not have corresponding pq coefficients. Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
c8f517c4 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5 revise rules for when to update metadata during reshape We currently update the metadata : 1/ every 3Megabytes 2/ When the place we will write new-layout data to is recorded in the metadata as still containing old-layout data. Rule one exists to avoid having to re-do too much reshaping in the face of a crash/restart. So it should really be time based rather than size based. So change it to "every 10 seconds". Rule two turns out to be too harsh when restriping an array 'in-place', as in that case the metadata much be updates for every stripe. For the in-place update, it can only possibly be safe from a crash if some user-space program data a backup of every e.g. few hundred stripes before allowing them to be reshaped. In that case, the constant metadata update is pointless. So only update the metadata if the new metadata will report that the end of the 'old-layout' data is beyond where we are currently writing 'new-layout' data. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b0f9ec04 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: minor code cleanups in make_request. ... and to be certain the that make_request doesn't wait forever, add a 'wake_up' when ->reshape_progress has been set to MaxSector Signed-off-by: NeilBrown <neilb@suse.de>
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#
2cffc4a0 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: remove CONFIG_MD_RAID_RESHAPE config option. This was only needed when the code was experimental. Most of it is well tested now, so the option is no longer useful. Signed-off-by: NeilBrown <neilb@suse.de>
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#
ab69ae12 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: be more careful about write ordering when reshaping. When we are reshaping an array, it is very important that we read the data from a particular sector offset before writing new data at that offset. In most cases when growing or shrinking an array we read long before we even consider writing. But when restriping an array without changing it size, there is a small possibility that we might have some data to available write before the read has happened at the same location. This would require some stripes to be in cache already. To guard against this small possibility, we check, before writing, that the 'old' stripe at the same location is not in the process of being read. And we ensure that we mark all 'source' stripes as such before allowing new 'destination' stripes to proceed. Signed-off-by: NeilBrown <neilb@suse.de>
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#
88ce4930 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: allow layout and chunksize to be changed on active array. If an array has 3 or more devices, we allow the chunksize or layout to be changed and when a reshape starts, we use these as the 'new' values. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7a661381 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: reshape using largest of old and new chunk size This ensures that even when old and new stripes are overlapping, we will try to read all of the old before having to write any of the new. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e183eaed |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: prepare for allowing reshape to change layout Add prev_algo to raid5_conf_t along the same lines as prev_chunk and previous_raid_disks. Signed-off-by: NeilBrown <neilb@suse.de>
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#
784052ec |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: prepare for allowing reshape to change chunksize. Add "prev_chunk" to raid5_conf_t, similar to "previous_raid_disks", to remember what the chunk size was before the reshape that is currently underway. This seems like duplication with "chunk_size" and "new_chunk" in mddev_t, and to some extent it is, but there are differences. The values in mddev_t are always defined and often the same. The prev* values are only defined if a reshape is underway. Also (and more significantly) the raid5_conf_t values will be changed at the same time (inside an appropriate lock) that the reshape is started by setting reshape_position. In contrast, the new_chunk value is set when the sysfs file is written which could be well before the reshape starts. Signed-off-by: NeilBrown <neilb@suse.de>
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#
86b42c71 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: clearly differentiate 'before' and 'after' stripes during reshape. During a raid5 reshape, we have some stripes in the cache that are 'before' the reshape (and are still to be processed) and some that are 'after'. They are currently differentiated by having different ->disks values as the only reshape current supported involves changing the number of disks. However we will soon support reshapes that do not change the number of disks (chunk parity or chunk size). So make the difference more explicit with a 'generation' number. Signed-off-by: NeilBrown <neilb@suse.de>
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#
ec32a2bd |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: allow number of drives in raid5 to be reduced When reshaping a raid5 to have fewer devices, we work from the end of the array to the beginning. md_do_sync gives addresses to sync_request that go from the beginning to the end. So largely ignore them use the internal state variable "reshape_progress" to keep track of what to do next. Never allow the size to be reduced below the minimum (4 for raid6, 3 otherwise). We require that the size of the array has already been reduced before the array is reshaped to a smaller size. This is because simply reducing the size is an easily reversible operation, while the reshape is immediately destructive and so is not reversible for the blocks at the ends of the devices. Thus to reshape an array to have fewer devices, you must first write an appropriately small size to md/array_size. When reshape finished, we remove any drives that are no longer needed and fix up ->degraded. Signed-off-by: NeilBrown <neilb@suse.de>
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#
fef9c61f |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: change reshape-progress measurement to cope with reshaping backwards. When reducing the number of devices in a raid4/5/6, the reshape process has to start at the end of the array and work down to the beginning. So we need to handle expand_progress and expand_lo differently. This patch renames "expand_progress" and "expand_lo" to avoid the implication that anything is getting bigger (expand->reshape) and every place they are used, we make sure that they are used the right way depending on whether delta_disks is positive or negative. Signed-off-by: NeilBrown <neilb@suse.de>
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#
cea9c228 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: add explicit method to signal the end of a reshape. Currently raid5 (the only module that supports restriping) notices that the reshape has finished be sync_request being given a large value, and handles any cleanup them. This patch changes it so md_check_recovery calls into an explicit finish_reshape method as well. The clean-up from sync_request can do things that need to be done promptly, typically things local to the raid5_conf_t structure. The "finish_reshape" method is called under the mddev_lock so it can do things involving reconfiguring the device. This allows us to get rid of md_set_array_sectors_locked, which would have caused a deadlock if you tried to stop and array while a reshape was happening. Signed-off-by: NeilBrown <neilb@suse.de>
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#
7ec05478 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: enhance raid5_size to work correctly with negative delta_disks This is the first of four patches which combine to allow md/raid5 to reduce the number of devices in the array by restriping the data over a subset of the devices. If the number of disks in a raid4/5/6 is being reduced, then the default size must be based on the new number, not the old number of devices. In general, it should be based on the smaller of new and old. Signed-off-by: NeilBrown <neilb@suse.de>
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#
34e04e87 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: drop qd_idx from r6_state We now have this value in stripe_head so we don't need to duplicate it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
f701d589 |
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30-Mar-2009 |
Dan Williams <dan.j.williams@intel.com> |
md/raid6: move raid6 data processing to raid6_pq.ko Move the raid6 data processing routines into a standalone module (raid6_pq) to prepare them to be called from async_tx wrappers and other non-md drivers/modules. This precludes a circular dependency of raid456 needing the async modules for data processing while those modules in turn depend on raid456 for the base level synchronous raid6 routines. To support this move: 1/ The exportable definitions in raid6.h move to include/linux/raid/pq.h 2/ The raid6_call, recovery calls, and table symbols are exported 3/ Extra #ifdef __KERNEL__ statements to enable the userspace raid6test to compile Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
18b00334 |
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30-Mar-2009 |
Andre Noll <maan@systemlinux.org> |
md: raid5 run(): Fix max_degraded for raid level 4. raid4 allows only one failed disk. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
b522adcd |
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30-Mar-2009 |
Dan Williams <dan.j.williams@intel.com> |
md: 'array_size' sysfs attribute Allow userspace to set the size of the array according to the following semantics: 1/ size must be <= to the size returned by mddev->pers->size(mddev, 0, 0) a) If size is set before the array is running, do_md_run will fail if size is greater than the default size b) A reshape attempt that reduces the default size to less than the set array size should be blocked 2/ once userspace sets the size the kernel will not change it 3/ writing 'default' to this attribute returns control of the size to the kernel and reverts to the size reported by the personality Also, convert locations that need to know the default size from directly reading ->array_sectors to <pers>_size. Resync/reshape operations always follow the default size. Finally, fixup other locations that read a number of 1k-blocks from userspace to use strict_blocks_to_sectors() which checks for unsigned long long to sector_t overflow and blocks to sectors overflow. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
1f403624 |
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30-Mar-2009 |
Dan Williams <dan.j.williams@intel.com> |
md: centralize ->array_sectors modifications Get personalities out of the business of directly modifying ->array_sectors. Lays groundwork to introduce policy on when ->array_sectors can be modified. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
80c3a6ce |
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17-Mar-2009 |
Dan Williams <dan.j.williams@intel.com> |
md: add 'size' as a personality method In preparation for giving userspace control over ->array_sectors we need to be able to retrieve the 'default' size, and the 'anticipated' size when a reshape is requested. For personalities that do not reshape emit a warning if anything but the default size is requested. In the raid5 case we need to update ->previous_raid_disks to make the new 'default' size available. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
fc9739c6 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: add takeover support for converting raid6 back into raid5 If a raid6 is still in the layout that comes from converting raid5 into a raid6. this will allow us to convert it back again. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e9d4758f |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: add takeover support for raid4 -> raid5 conversion. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b3546035 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: allow layout/chunksize to be changed on an active 2-drive raid5. 2-drive raid5's aren't very interesting. But if you are converting a raid1 into a raid5, you will at least temporarily have one. And that it a good time to set the layout/chunksize for the new RAID5 if you aren't happy with the defaults. layout and chunksize don't actually affect the placement of data on a 2-drive raid5, so we just do some internal book-keeping. Signed-off-by: NeilBrown <neilb@suse.de>
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#
d562b0c4 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: add ->takeover method for raid5 to be able to take over raid1 The RAID1 must have two drives and be a suitable size to be a multiple of a chunksize that isn't too small. Signed-off-by: NeilBrown <neilb@suse.de>
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#
245f46c2 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: add ->takeover method to support changing the personality managing an array Implement this for RAID6 to be able to 'takeover' a RAID5 array. The new RAID6 will use a layout which places Q on the last device, and that device will be missing. If there are any available spares, one will immediately have Q recovered onto it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
e0cf8f04 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: md_unregister_thread should cope with being passed NULL Mostly md_unregister_thread is only called when we know that the thread is NULL, but sometimes we need to check first. It is safer to put the check inside md_unregister_thread itself. Signed-off-by: NeilBrown <neilb@suse.de>
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#
91adb564 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: refactor raid5 "run" .. so that the code to create the private data structures is separate. This will help with future code to change the level of an active array. Signed-off-by: NeilBrown <neilb@suse.de>
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#
67cc2b81 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: finish support for DDF/raid6 DDF requires RAID6 calculations over different devices in a different order. For md/raid6, we calculate over just the data devices, starting immediately after the 'Q' block. For ddf/raid6 we calculate over all devices, using zeros in place of the P and Q blocks. This requires unfortunately complex loops... Signed-off-by: NeilBrown <neilb@suse.de>
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#
99c0fb5f |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: Add support for new layouts for raid5 and raid6. DDF uses different layouts for P and Q blocks than current md/raid6 so add those that are missing. Also add support for RAID6 layouts that are identical to various raid5 layouts with the simple addition of one device to hold all of the 'Q' blocks. Finally add 'raid5' layouts to match raid4. These last to will allow online level conversion. Note that this does not provide correct support for DDF/raid6 yet as the order in which data blocks are summed to produce the Q block is significant and different between current md code and DDF requirements. Signed-off-by: NeilBrown <neilb@suse.de>
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#
911d4ee8 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: simplify raid5_compute_sector interface Rather than passing 'pd_idx' and 'qd_idx' to be filled in, pass a 'struct stripe_head *' and fill in the relevant fields. This is more extensible. Signed-off-by: NeilBrown <neilb@suse.de>
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#
d0dabf7e |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid6: remove expectation that Q device is immediately after P device. Code currently assumes that the devices in a raid6 stripe are 0 1 ... N-1 P Q in some rotated order. We will shortly add new layouts in which this strict pattern is broken. So remove this expectation. We still assume that the data disks are roughly in-order. However P and Q can be inserted anywhere within that order. Signed-off-by: NeilBrown <neilb@suse.de>
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#
112bf897 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: change raid5_compute_sector and stripe_to_pdidx to take a 'previous' argument This similar to the recent change to get_active_stripe. There is no functional change, just come rearrangement to make future patches cleaner. Signed-off-by: NeilBrown <neilb@suse.de>
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#
b5663ba4 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md/raid5: simplify interface for init_stripe and get_active_stripe Rather than passing 'pd_idx' and 'disks' to these functions, just pass 'previous' which tells whether to use the 'previous' or 'current' geometry during a reshape, and let init_stripe calculate disks and pd_idx and anything else it might need. This is not a substantial simplification and even adds a division. However we will shortly be adding more complexity to init_stripe to handle more interesting 'reshape' activities, and without this change, the interface to these functions would get very complex. Signed-off-by: NeilBrown <neilb@suse.de>
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#
58c0fed4 |
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30-Mar-2009 |
Andre Noll <maan@systemlinux.org> |
md: Make mddev->size sector-based. This patch renames the "size" field of struct mddev_s to "dev_sectors" and stores the number of 512-byte sectors instead of the number of 1K-blocks in it. All users of that field, including raid levels 1,4-6,10, are adjusted accordingly. This simplifies the code a bit because it allows to get rid of a couple of divisions/multiplications by two. In order to make checkpatch happy, some minor coding style issues have also been addressed. In particular, size_store() now uses strict_strtoull() instead of simple_strtoull(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
43b2e5d8 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: move md_k.h from include/linux/raid/ to drivers/md/ It really is nicer to keep related code together.. Signed-off-by: NeilBrown <neilb@suse.de>
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#
bff61975 |
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30-Mar-2009 |
NeilBrown <neilb@suse.de> |
md: move lots of #include lines out of .h files and into .c This makes the includes more explicit, and is preparation for moving md_k.h to drivers/md/md.h Remove include/raid/md.h as its only remaining use was to #include other files. Signed-off-by: NeilBrown <neilb@suse.de>
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#
ef740c37 |
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30-Mar-2009 |
Christoph Hellwig <hch@lst.de> |
md: move headers out of include/linux/raid/ Move the headers with the local structures for the disciplines and bitmap.h into drivers/md/ so that they are more easily grepable for hacking and not far away. md.h is left where it is for now as there are some uses from the outside. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.de>
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#
159ec1fc |
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08-Jan-2009 |
Cheng Renquan <crquan@gmail.com> |
md: use list_for_each_entry macro directly The rdev_for_each macro defined in <linux/raid/md_k.h> is identical to list_for_each_entry_safe, from <linux/list.h>, it should be defined to use list_for_each_entry_safe, instead of reinventing the wheel. But some calls to each_entry_safe don't really need a safe version, just a direct list_for_each_entry is enough, this could save a temp variable (tmp) in every function that used rdev_for_each. In this patch, most rdev_for_each loops are replaced by list_for_each_entry, totally save many tmp vars; and only in the other situations that will call list_del to delete an entry, the safe version is used. Signed-off-by: Cheng Renquan <crquan@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
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#
4bbf3771 |
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12-Oct-2008 |
NeilBrown <neilb@suse.de> |
md: Relax minimum size restrictions on chunk_size. Currently, the 'chunk_size' of an array must be at-least PAGE_SIZE. This makes moving an array to a machine with a larger PAGE_SIZE, or changing the kernel to use a larger PAGE_SIZE, can stop an array from working. For RAID10 and RAID4/5/6, this is non-trivial to fix as the resync process works on whole pages at a time, and assumes them to be wholly within a stripe. For other raid personalities, this restriction is not needed at all and can be dropped. So remove the test on chunk_size from common can, and add it in just the places where it is needed: raid10 and raid4/5/6. Signed-off-by: NeilBrown <neilb@suse.de>
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#
d710e138 |
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12-Oct-2008 |
NeilBrown <neilb@suse.de> |
md: remove space after function name in declaration and call. Having function (args) instead of function(args) make is harder to search for calls of particular functions. So remove all those spaces. Signed-off-by: NeilBrown <neilb@suse.de>
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#
fb4d8c76 |
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12-Oct-2008 |
NeilBrown <neilb@suse.de> |
md: Remove unnecessary #includes, #defines, and function declarations. A lot of cruft has gathered over the years. Time to remove it. Signed-off-by: NeilBrown <neilb@suse.de>
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#
074a7aca |
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25-Aug-2008 |
Tejun Heo <tj@kernel.org> |
block: move stats from disk to part0 Move stats related fields - stamp, in_flight, dkstats - from disk to part0 and unify stat handling such that... * part_stat_*() now updates part0 together if the specified partition is not part0. ie. part_stat_*() are now essentially all_stat_*(). * {disk|all}_stat_*() are gone. * part_round_stats() is updated similary. It handles part0 stats automatically and disk_round_stats() is killed. * part_{inc|dec}_in_fligh() is implemented which automatically updates part0 stats for parts other than part0. * disk_map_sector_rcu() is updated to return part0 if no part matches. Combined with the above changes, this makes NULL special case handling in callers unnecessary. * Separate stats show code paths for disk are collapsed into part stats show code paths. * Rename disk_stat_lock/unlock() to part_stat_lock/unlock() While at it, reposition stat handling macros a bit and add missing parentheses around macro parameters. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
c9959059 |
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25-Aug-2008 |
Tejun Heo <tj@kernel.org> |
block: fix diskstats access There are two variants of stat functions - ones prefixed with double underbars which don't care about preemption and ones without which disable preemption before manipulating per-cpu counters. It's unclear whether the underbarred ones assume that preemtion is disabled on entry as some callers don't do that. This patch unifies diskstats access by implementing disk_stat_lock() and disk_stat_unlock() which take care of both RCU (for partition access) and preemption (for per-cpu counter access). diskstats access should always be enclosed between the two functions. As such, there's no need for the versions which disables preemption. They're removed and double underbars ones are renamed to drop the underbars. As an extra argument is added, there's no danger of using the old version unconverted. disk_stat_lock() uses get_cpu() and returns the cpu index and all diskstat functions which access per-cpu counters now has @cpu argument to help RT. This change adds RCU or preemption operations at some places but also collapses several preemption ops into one at others. Overall, the performance difference should be negligible as all involved ops are very lightweight per-cpu ones. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
5b99c2ff |
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15-Aug-2008 |
Jens Axboe <jens.axboe@oracle.com> |
block: make bi_phys_segments an unsigned int instead of short raid5 can overflow with more than 255 stripes, and we can increase it to an int for free on both 32 and 64-bit archs due to the padding. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
960e739d |
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15-Aug-2008 |
Jens Axboe <jens.axboe@oracle.com> |
block: raid fixups for removal of bi_hw_segments Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
ac4090d2 |
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04-Aug-2008 |
NeilBrown <neilb@suse.de> |
Don't let a blocked_rdev interfere with read request in raid5/6 When we have externally managed metadata, we need to mark a failed device as 'Blocked' and not allow any writes until that device have been marked as faulty in the metadata and the Blocked flag has been removed. However it is perfectly OK to allow read requests when there is a Blocked device, and with a readonly array, there may not be any metadata-handler watching for blocked devices. So in raid5/raid6 only allow a Blocked device to interfere with Write request or resync. Read requests go through untouched. raid1 and raid10 already differentiate between read and write properly. Signed-off-by: NeilBrown <neilb@suse.de>
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#
dba034ee |
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04-Aug-2008 |
NeilBrown <neilb@suse.de> |
Fail safely when trying to grow an array with a write-intent bitmap. We cannot currently change the size of a write-intent bitmap. So if we change the size of an array which has such a bitmap, it tries to set bits beyond the end of the bitmap. For now, simply reject any request to change the size of an array which has a bitmap. mdadm can remove the bitmap and add a new one after the array has changed size. Signed-off-by: NeilBrown <neilb@suse.de>
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#
df10cfbc |
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29-Jul-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: do not progress the resync process if the stripe was blocked handle_stripe will take no action on a stripe when waiting for userspace to unblock the array, so do not report completed sectors. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
23397883 |
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23-Jul-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: fix merge error The original STRIPE_OP_IO removal patch had the following hunk: - for (i = conf->raid_disks; i--; ) { + for (i = conf->raid_disks; i--; ) set_bit(R5_Wantwrite, &sh->dev[i].flags); - if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) - sh->ops.count++; - } However it appears the hunk became broken after merging: - for (i = conf->raid_disks; i--; ) { + for (i = conf->raid_disks; i--; ) set_bit(R5_Wantwrite, &sh->dev[i].flags); set_bit(R5_LOCKED, &dev->flags); s.locked++; - if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) - sh->ops.count++; - } Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
c9f21aaf |
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23-Jul-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: move async_tx_issue_pending_all outside spin_lock_irq Some dma drivers need to call spin_lock_bh in their device_issue_pending routines. This change avoids: WARNING: at kernel/softirq.c:136 local_bh_enable_ip+0x3a/0x85() Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
f233ea5c |
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21-Jul-2008 |
Andre Noll <maan@systemlinux.org> |
md: Make mddev->array_size sector-based. This patch renames the array_size field of struct mddev_s to array_sectors and converts all instances to use units of 512 byte sectors instead of 1k blocks. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
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#
7a1fc53c |
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10-Jul-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: ensure all blocks are uptodate or locked when syncing Remove the dubious attempt to prefer 'compute' over 'read'. Not only is it wrong given commit c337869d (md: do not compute parity unless it is on a failed drive), but it can trigger a BUG_ON in handle_parity_checks5(). Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
cc371e66 |
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03-Jul-2008 |
Alasdair G Kergon <agk@redhat.com> |
Add bvec_merge_data to handle stacked devices and ->merge_bvec() When devices are stacked, one device's merge_bvec_fn may need to perform the mapping and then call one or more functions for its underlying devices. The following bio fields are used: bio->bi_sector bio->bi_bdev bio->bi_size bio->bi_rw using bio_data_dir() This patch creates a new struct bvec_merge_data holding a copy of those fields to avoid having to change them directly in the struct bio when going down the stack only to have to change them back again on the way back up. (And then when the bio gets mapped for real, the whole exercise gets repeated, but that's a problem for another day...) Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: Neil Brown <neilb@suse.de> Cc: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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#
b5470dc5 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: resolve external metadata handling deadlock in md_allow_write md_allow_write() marks the metadata dirty while holding mddev->lock and then waits for the write to complete. For externally managed metadata this causes a deadlock as userspace needs to take the lock to communicate that the metadata update has completed. Change md_allow_write() in the 'external' case to start the 'mark active' operation and then return -EAGAIN. The expected side effects while waiting for userspace to write 'active' to 'array_state' are holding off reshape (code currently handles -ENOMEM), cause some 'stripe_cache_size' change requests to fail, cause some GET_BITMAP_FILE ioctl requests to fall back to GFP_NOIO, and cause updates to 'raid_disks' to fail. Except for 'stripe_cache_size' changes these failures can be mitigated by coordinating with mdmon. md_write_start() still prevents writes from occurring until the metadata handler has had a chance to take action as it unconditionally waits for MD_CHANGE_CLEAN to be cleared. [neilb@suse.de: return -EAGAIN, try GFP_NOIO] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
1fe797e6 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: rationalize raid5 function names From: Dan Williams <dan.j.williams@intel.com> Commit a4456856 refactored some of the deep code paths in raid5.c into separate functions. The names chosen at the time do not consistently indicate what is going to happen to the stripe. So, update the names, and since a stripe is a cache element use cache semantics like fill, dirty, and clean. (also, fix up the indentation in fetch_block5) Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
7b3a871e |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: handle operation chaining in raid5_run_ops From: Dan Williams <dan.j.williams@intel.com> Neil said: > At the end of ops_run_compute5 you have: > /* ack now if postxor is not set to be run */ > if (tx && !test_bit(STRIPE_OP_POSTXOR, &s->ops_run)) > async_tx_ack(tx); > > It looks odd having that test there. Would it fit in raid5_run_ops > better? The intended global interpretation is that raid5_run_ops can build a chain of xor and memcpy operations. When MD registers the compute-xor it tells async_tx to keep the operation handle around so that another item in the dependency chain can be submitted. If we are just computing a block to satisfy a read then we can terminate the chain immediately. raid5_run_ops gives a better context for this test since it cares about the entire chain. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
d8ee0728 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: replace R5_WantPrexor with R5_WantDrain, add 'prexor' reconstruct_states From: Dan Williams <dan.j.williams@intel.com> Currently ops_run_biodrain and other locations have extra logic to determine which blocks are processed in the prexor and non-prexor cases. This can be eliminated if handle_write_operations5 flags the blocks to be processed in all cases via R5_Wantdrain. The presence of the prexor operation is tracked in sh->reconstruct_state. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
600aa109 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: replace STRIPE_OP_{BIODRAIN,PREXOR,POSTXOR} with 'reconstruct_states' From: Dan Williams <dan.j.williams@intel.com> Track the state of reconstruct operations (recalculating the parity block usually due to incoming writes, or as part of array expansion) Reduces the scope of the STRIPE_OP_{BIODRAIN,PREXOR,POSTXOR} flags to only tracking whether a reconstruct operation has been requested via the ops_request field of struct stripe_head_state. This is the final step in the removal of ops.{pending,ack,complete,count}, i.e. the STRIPE_OP_{BIODRAIN,PREXOR,POSTXOR} flags only request an operation and do not track the state of the operation. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
976ea8d4 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: replace STRIPE_OP_COMPUTE_BLK with STRIPE_COMPUTE_RUN From: Dan Williams <dan.j.williams@intel.com> Track the state of compute operations (recalculating a block from all the other blocks in a stripe) with a state flag. Reduces the scope of the STRIPE_OP_COMPUTE_BLK flag to only tracking whether a compute operation has been requested via the ops_request field of struct stripe_head_state. Note, the compute operation that is performed in the course of doing a 'repair' operation (check the parity block, recalculate it and write it back if the check result is not zero) is tracked separately with the 'check_state' variable. Compute operations are held off while a 'check' is in progress, and moving this check out to handle_issuing_new_read_requests5 the helper routine __handle_issuing_new_read_requests5 can be simplified. This is another step towards the removal of ops.{pending,ack,complete,count}, i.e. STRIPE_OP_COMPUTE_BLK only requests an operation and does not track the state of the operation. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
83de75cc |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: replace STRIPE_OP_BIOFILL with STRIPE_BIOFILL_RUN From: Dan Williams <dan.j.williams@intel.com> Track the state of read operations (copying data from the stripe cache to bio buffers outside the lock) with a state flag. Reduce the scope of the STRIPE_OP_BIOFILL flag to only tracking whether a biofill operation has been requested via the ops_request field of struct stripe_head_state. This is another step towards the removal of ops.{pending,ack,complete,count}, i.e. STRIPE_OP_BIOFILL only requests an operation and does not track the state of the operation. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
ecc65c9b |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: replace STRIPE_OP_CHECK with 'check_states' From: Dan Williams <dan.j.williams@intel.com> The STRIPE_OP_* flags record the state of stripe operations which are performed outside the stripe lock. Their use in indicating which operations need to be run is straightforward; however, interpolating what the next state of the stripe should be based on a given combination of these flags is not straightforward, and has led to bugs. An easier to read implementation with minimal degrees of freedom is needed. Towards this goal, this patch introduces explicit states to replace what was previously interpolated from the STRIPE_OP_* flags. For now this only converts the handle_parity_checks5 path, removing a user of the ops.{pending,ack,complete,count} fields of struct stripe_operations. This conversion also found a remaining issue with the current code. There is a small window for a drive to fail between when we schedule a repair and when the parity calculation for that repair completes. When this happens we will writeback to 'failed_num' when we really want to write back to 'pd_idx'. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
f0e43bcd |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: unify raid5/6 i/o submission From: Dan Williams <dan.j.williams@intel.com> Let the raid6 path call ops_run_io to get pending i/o submitted. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
c4e5ac0a |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: use stripe_head_state in ops_run_io() From: Dan Williams <dan.j.williams@intel.com> In handle_stripe after taking sh->lock we sample some bits into 's' (struct stripe_head_state): s.syncing = test_bit(STRIPE_SYNCING, &sh->state); s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); Use these values from 's' in ops_run_io() rather than re-sampling the bits. This ensures a consistent snapshot (as seen under sh->lock) is used. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
2b7497f0 |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: kill STRIPE_OP_IO flag From: Dan Williams <dan.j.williams@intel.com> The R5_Want{Read,Write} flags already gate i/o. So, this flag is superfluous and we can unconditionally call ops_run_io(). Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
b203886e |
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27-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: kill STRIPE_OP_MOD_DMA in raid5 offload From: Dan Williams <dan.j.williams@intel.com> This micro-optimization allowed the raid code to skip a re-read of the parity block after checking parity. It took advantage of the fact that xor-offload-engines have their own internal result buffer and can check parity without writing to memory. Remove it for the following reasons: 1/ It is a layering violation for MD to need to manage the DMA and non-DMA paths within async_xor_zero_sum 2/ Bad precedent to toggle the 'ops' flags outside the lock 3/ Hard to realize a performance gain as reads will not need an updated parity block and writes will dirty it anyways. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de>
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#
199050ea |
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27-Jun-2008 |
Neil Brown <neilb@notabene.brown> |
rationalise return value for ->hot_add_disk method. For all array types but linear, ->hot_add_disk returns 1 on success, 0 on failure. For linear, it returns 0 on success and -errno on failure. This doesn't cause a functional problem because the ->hot_add_disk function of linear is used quite differently to the others. However it is confusing. So convert all to return 0 for success or -errno on failure and fix call sites to match. Signed-off-by: Neil Brown <neilb@suse.de>
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#
6c2fce2e |
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27-Jun-2008 |
Neil Brown <neilb@notabene.brown> |
Support adding a spare to a live md array with external metadata. i.e. extend the 'md/dev-XXX/slot' attribute so that you can tell a device to fill an vacant slot in an and md array. Signed-off-by: Neil Brown <neilb@suse.de>
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#
0e13fe23 |
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27-Jun-2008 |
Neil Brown <neilb@notabene.brown> |
use bio_endio instead of a call to bi_end_io Turn calls to bi->bi_end_io() into bio_endio(). Apparently bio_endio does exactly the same error processing as is hardcoded at these places. bio_endio() avoids recursion (or will soon), so it should be used. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Neil Brown <neilb@suse.de>
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efe31143 |
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27-Jun-2008 |
Neil Brown <neilb@notabene.brown> |
Don't acknowlege that stripe-expand is complete until it really is. We shouldn't acknowledge that a stripe has been expanded (When reshaping a raid5 by adding a device) until the moved data has actually been written out. However we are currently acknowledging (by calling md_done_sync) when the POST_XOR is complete and before the write. So track in s.locked whether there are pending writes, and don't call md_done_sync yet if there are. Note: we all set R5_LOCKED on devices which are are about to read from. This probably isn't technically necessary, but is usually done when writing a block, and justifies the use of s.locked here. This bug can lead to a crash if an array is stopped while an reshape is in progress. Cc: <stable@kernel.org> Signed-off-by: Neil Brown <neilb@suse.de>
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#
8c2e870a |
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27-Jun-2008 |
Neil Brown <neilb@notabene.brown> |
Ensure interrupted recovery completed properly (v1 metadata plus bitmap) If, while assembling an array, we find a device which is not fully in-sync with the array, it is important to set the "fullsync" flags. This is an exact analog to the setting of this flag in hot_add_disk methods. Currently, only v1.x metadata supports having devices in an array which are not fully in-sync (it keep track of how in sync they are). The 'fullsync' flag only makes a difference when a write-intent bitmap is being used. In this case it tells recovery to ignore the bitmap and recovery all blocks. This fix is already in place for raid1, but not raid5/6 or raid10. So without this fix, a raid1 ir raid4/5/6 array with version 1.x metadata and a write intent bitmaps, that is stopped in the middle of a recovery, will appear to complete the recovery instantly after it is reassembled, but the recovery will not be correct. If you might have an array like that, issueing echo repair > /sys/block/mdXX/md/sync_action will make sure recovery completes properly. Cc: <stable@kernel.org> Signed-off-by: Neil Brown <neilb@suse.de>
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#
c337869d |
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05-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: do not compute parity unless it is on a failed drive If a block is computed (rather than read) then a check/repair operation may be lead to believe that the data on disk is correct, when infact it isn't. So only compute blocks for failed devices. This issue has been around since at least 2.6.12, but has become harder to hit in recent kernels since most reads bypass the cache. echo repair > /sys/block/mdN/md/sync_action will set the parity blocks to the correct state. Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
e0a115e5 |
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05-Jun-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: fix prexor vs sync_request race During the initial array synchronization process there is a window between when a prexor operation is scheduled to a specific stripe and when it completes for a sync_request to be scheduled to the same stripe. When this happens the prexor completes and the stripe is unconditionally marked "insync", effectively canceling the sync_request for the stripe. Prior to 2.6.23 this was not a problem because the prexor operation was done under sh->lock. The effect in older kernels being that the prexor would still erroneously mark the stripe "insync", but sync_request would be held off and re-mark the stripe as "!in_sync". Change the write completion logic to not mark the stripe "in_sync" if a prexor was performed. The effect of the change is to sometimes not set STRIPE_INSYNC. The worst this can do is cause the resync to stall waiting for STRIPE_INSYNC to be set. If this were happening, then STRIPE_SYNCING would be set and handle_issuing_new_read_requests would cause all available blocks to eventually be read, at which point prexor would never be used on that stripe any more and STRIPE_INSYNC would eventually be set. echo repair > /sys/block/mdN/md/sync_action will correct arrays that may have lost this race. Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
dfc70645 |
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23-May-2008 |
NeilBrown <neilb@suse.de> |
md: restart recovery cleanly after device failure. When we get any IO error during a recovery (rebuilding a spare), we abort the recovery and restart it. For RAID6 (and multi-drive RAID1) it may not be best to restart at the beginning: when multiple failures can be tolerated, the recovery may be able to continue and re-doing all that has already been done doesn't make sense. We already have the infrastructure to record where a recovery is up to and restart from there, but it is not being used properly. This is because: - We sometimes abort with MD_RECOVERY_ERR rather than just MD_RECOVERY_INTR, which causes the recovery not be be checkpointed. - We remove spares and then re-added them which loses important state information. The distinction between MD_RECOVERY_ERR and MD_RECOVERY_INTR really isn't needed. If there is an error, the relevant drive will be marked as Faulty, and that is enough to ensure correct handling of the error. So we first remove MD_RECOVERY_ERR, changing some of the uses of it to MD_RECOVERY_INTR. Then we cause the attempt to remove a non-faulty device from an array to fail (unless recovery is impossible as the array is too degraded). Then when remove_and_add_spares attempts to remove the devices on which recovery can continue, it will fail, they will remain in place, and recovery will continue on them as desired. Issue: If we are halfway through rebuilding a spare and another drive fails, and a new spare is immediately available, do we want to: 1/ complete the current rebuild, then go back and rebuild the new spare or 2/ restart the rebuild from the start and rebuild both devices in parallel. Both options can be argued for. The code currently takes option 2 as a/ this requires least code change b/ this results in a minimally-degraded array in minimal time. Cc: "Eivind Sarto" <ivan@kasenna.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
6be9d494 |
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23-May-2008 |
Bernd Schubert <bernd-schubert@gmx.de> |
md: md: raid5 rate limit error printk Last night we had scsi problems and a hardware raid unit was offlined during heavy i/o. While this happened we got for about 3 minutes a huge number messages like these Apr 12 03:36:07 pfs1n14 kernel: [197510.696595] raid5:md7: read error not correctable (sector 2993096568 on sdj2). I guess the high error rate is responsible for not scheduling other events - during this time the system was not pingable and in the end also other devices run into scsi command timeouts causing problems on these unrelated devices as well. Signed-off-by: Bernd Schubert <bernd-schubert@gmx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
e7e72bf6 |
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14-May-2008 |
Neil Brown <neilb@suse.de> |
Remove blkdev warning triggered by using md As setting and clearing queue flags now requires that we hold a spinlock on the queue, and as blk_queue_stack_limits is called without that lock, get the lock inside blk_queue_stack_limits. For blk_queue_stack_limits to be able to find the right lock, each md personality needs to set q->queue_lock to point to the appropriate lock. Those personalities which didn't previously use a spin_lock, us q->__queue_lock. So always initialise that lock when allocated. With this in place, setting/clearing of the QUEUE_FLAG_PLUGGED bit will no longer cause warnings as it will be clear that the proper lock is held. Thanks to Dan Williams for review and fixing the silly bugs. Signed-off-by: NeilBrown <neilb@suse.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Alistair John Strachan <alistair@devzero.co.uk> Cc: Nick Piggin <npiggin@suse.de> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Jacek Luczak <difrost.kernel@gmail.com> Cc: Prakash Punnoor <prakash@punnoor.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
c8894419 |
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12-May-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: fix raid5 'repair' operations commit bd2ab67030e9116f1e4aae1289220255412b37fd "md: close a livelock window in handle_parity_checks5" introduced a bug in handling 'repair' operations. After a repair operation completes we clear the state bits tracking this operation. However, they are cleared too early and this results in the code deciding to re-run the parity check operation. Since we have done the repair in memory the second check does not find a mismatch and thus does not do a writeback. Test results: $ echo repair > /sys/block/md0/md/sync_action $ cat /sys/block/md0/md/mismatch_cnt 51072 $ echo repair > /sys/block/md0/md/sync_action $ cat /sys/block/md0/md/mismatch_cnt 0 (also fix incorrect indentation) Cc: <stable@kernel.org> Tested-by: George Spelvin <linux@horizon.com> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
6bfe0b49 |
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30-Apr-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: support blocking writes to an array on device failure Allows a userspace metadata handler to take action upon detecting a device failure. Based on an original patch by Neil Brown. Changes: -added blocked_wait waitqueue to rdev -don't qualify Blocked with Faulty always let userspace block writes -added md_wait_for_blocked_rdev to wait for the block device to be clear, if userspace misses the notification another one is sent every 5 seconds -set MD_RECOVERY_NEEDED after clearing "blocked" -kill DoBlock flag, just test mddev->external Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
d7a420c9 |
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28-Apr-2008 |
Nick Andrew <nick@nick-andrew.net> |
raid: remove leading TAB on printk messages MD drivers use one printk() call to print 2 log messages and the second line may be prefixed by a TAB character. It may also output a trailing space before newline. klogd (I think) turns the TAB character into the 2 characters '^I' when logging to a file. This looks ugly. Instead of a leading TAB to indicate continuation, prefix both output lines with 'raid:' or similar. Also remove any trailing space in the vicinity of the affected code and consistently end the sentences with a period. Signed-off-by: Nick Andrew <nick@nick-andrew.net> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
4ef197d8 |
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28-Apr-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: raid5.c convert simple_strtoul to strict_strtoul strict_strtoul handles the open-coded sanity checks in raid5_store_stripe_cache_size and raid5_store_preread_threshold Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
8b3e6cdc |
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28-Apr-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: introduce get_priority_stripe() to improve raid456 write performance Improve write performance by preventing the delayed_list from dumping all its stripes onto the handle_list in one shot. Delayed stripes are now further delayed by being held on the 'hold_list'. The 'hold_list' is bypassed when: * a STRIPE_IO_STARTED stripe is found at the head of 'handle_list' * 'handle_list' is empty and i/o is being done to satisfy full stripe-width write requests * 'bypass_count' is less than 'bypass_threshold'. By default the threshold is 1, i.e. every other stripe handled is a preread stripe provided the top two conditions are false. Benchmark data: System: 2x Xeon 5150, 4x SATA, mem=1GB Baseline: 2.6.24-rc7 Configuration: mdadm --create /dev/md0 /dev/sd[b-e] -n 4 -l 5 --assume-clean Test1: dd if=/dev/zero of=/dev/md0 bs=1024k count=2048 * patched: +33% (stripe_cache_size = 256), +25% (stripe_cache_size = 512) Test2: tiobench --size 2048 --numruns 5 --block 4096 --block 131072 (XFS) * patched: +13% * patched + preread_bypass_threshold = 0: +37% Changes since v1: * reduce bypass_threshold from (chunk_size / sectors_per_chunk) to (1) and make it configurable. This defaults to fairness and modest performance gains out of the box. Changes since v2: * [neilb@suse.de]: kill STRIPE_PRIO_HI and preread_needed as they are not necessary, the important change was clearing STRIPE_DELAYED in add_stripe_bio and this has been moved out to make_request for the hang fix. * [neilb@suse.de]: simplify get_priority_stripe * [dan.j.williams@intel.com]: reset the bypass_count when ->hold_list is sampled empty (+11%) * [dan.j.williams@intel.com]: decrement the bypass_count at the detection of stripes being naturally promoted off of hold_list +2%. Note, resetting bypass_count instead of decrementing on these events yields +4% but that is probably too aggressive. Changes since v3: * cosmetic fixups Tested-by: James W. Laferriere <babydr@baby-dragons.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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e46b272b |
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28-Apr-2008 |
Harvey Harrison <harvey.harrison@gmail.com> |
md: replace remaining __FUNCTION__ occurrences __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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bd2ab670 |
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10-Apr-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: close a livelock window in handle_parity_checks5 If a failure is detected after a parity check operation has been initiated, but before it completes handle_parity_checks5 will never quiesce operations on the stripe. Explicitly handle this case by "canceling" the parity check, i.e. clear the STRIPE_OP_CHECK flags and queue the stripe on the handle list again to refresh any non-uptodate blocks. Kernel versions >= 2.6.23 are susceptible. Cc: <stable@kernel.org> Cc: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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9ea85eba |
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19-Mar-2008 |
Andrew Morton <akpm@linux-foundation.org> |
drivers/md/raid5.c: fix printk warnings gcc-3.4.5 on sparc64: drivers/md/raid5.c: In function `raid5_end_read_request': drivers/md/raid5.c:1147: warning: long long unsigned int format, long unsigned int arg (arg 4) drivers/md/raid5.c:1164: warning: long long unsigned int format, long unsigned int arg (arg 3) drivers/md/raid5.c:1170: warning: long long unsigned int format, long unsigned int arg (arg 3) sector_t is u64, and we don't know what type the architecture uses to implement u64 (on some it is unsigned long). Cc: Neil Brown <neilb@suse.de> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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6ed3003c |
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06-Feb-2008 |
NeilBrown <neilb@suse.de> |
md: fix an occasional deadlock in raid5 raid5's 'make_request' function calls generic_make_request on underlying devices and if we run out of stripe heads, it could end up waiting for one of those requests to complete. This is bad as recursive calls to generic_make_request go on a queue and are not even attempted until make_request completes. So: don't make any generic_make_request calls in raid5 make_request until all waiting has been done. We do this by simply setting STRIPE_HANDLE instead of calling handle_stripe(). If we need more stripe_heads, raid5d will get called to process the pending stripe_heads which will call generic_make_request from a This change by itself causes a performance hit. So add a change so that raid5_activate_delayed is only called at unplug time, never in raid5. This seems to bring back the performance numbers. Calling it in raid5d was sometimes too soon... Neil said: How about we queue it for 2.6.25-rc1 and then about when -rc2 comes out, we queue it for 2.6.24.y? Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Tested-by: dean gaudet <dean@arctic.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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d089c6af |
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06-Feb-2008 |
NeilBrown <neilb@suse.de> |
md: change ITERATE_RDEV to rdev_for_each As this is more in line with common practice in the kernel. Also swap the args around to be more like list_for_each. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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c6207277 |
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06-Feb-2008 |
NeilBrown <neilb@suse.de> |
md: allow a maximum extent to be set for resyncing This allows userspace to control resync/reshape progress and synchronise it with other activities, such as shared access in a SAN, or backing up critical sections during a tricky reshape. Writing a number of sectors (which must be a multiple of the chunk size if such is meaningful) causes a resync to pause when it gets to that point. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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b47490c9 |
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06-Feb-2008 |
NeilBrown <neilb@suse.de> |
md: Update md bitmap during resync. Currently an md array with a write-intent bitmap does not updated that bitmap to reflect successful partial resync. Rather the entire bitmap is updated when the resync completes. This is because there is no guarentee that resync requests will complete in order, and tracking each request individually is unnecessarily burdensome. However there is value in regularly updating the bitmap, so add code to periodically pause while all pending sync requests complete, then update the bitmap. Doing this only every few seconds (the same as the bitmap update time) does not notciably affect resync performance. [snitzer@gmail.com: export bitmap_cond_end_sync] Signed-off-by: Neil Brown <neilb@suse.de> Cc: "Mike Snitzer" <snitzer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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0f94e87c |
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08-Jan-2008 |
Dan Williams <dan.j.williams@intel.com> |
md: fix data corruption when a degraded raid5 array is reshaped We currently do not wait for the block from the missing device to be computed from parity before copying data to the new stripe layout. The change in the raid6 code is not techincally needed as we don't delay data block recovery in the same way for raid6 yet. But making the change now is safer long-term. This bug exists in 2.6.23 and 2.6.24-rc Cc: <stable@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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6c55be8b |
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14-Nov-2007 |
Dan Williams <dan.j.williams@intel.com> |
raid5: fix unending write sequence <debug output from Joel's system> handling stripe 7629696, state=0x14 cnt=1, pd_idx=2 ops=0:0:0 check 5: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ffcffcc0 written 0000000000000000 check 4: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fdd4e360 written 0000000000000000 check 3: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000 check 2: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000 check 1: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ff517e40 written 0000000000000000 check 0: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fd4cae60 written 0000000000000000 locked=4 uptodate=2 to_read=0 to_write=4 failed=0 failed_num=0 for sector 7629696, rmw=0 rcw=0 </debug> These blocks were prepared to be written out, but were never handled in ops_run_biodrain(), so they remain locked forever. The operations flags are all clear which means handle_stripe() thinks nothing else needs to be done. This state suggests that the STRIPE_OP_PREXOR bit was sampled 'set' when it should not have been. This patch cleans up cases where the code looks at sh->ops.pending when it should be looking at the consistent stack-based snapshot of the operations flags. Report from Joel: Resync done. Patch fix this bug. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Joel Bertrand <joel.bertrand@systella.fr> Cc: <stable@kernel.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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2ad8b1ef |
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07-Nov-2007 |
Alan D. Brunelle <Alan.Brunelle@hp.com> |
Add UNPLUG traces to all appropriate places Added blk_unplug interface, allowing all invocations of unplugs to result in a generated blktrace UNPLUG. Signed-off-by: Alan D. Brunelle <Alan.Brunelle@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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def6ae26 |
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05-Nov-2007 |
Neil Brown <neilb@suse.de> |
md: fix misapplied patch in raid5.c commit 4ae3f847e49e3787eca91bced31f8fd328d50496 ("md: raid5: fix clearing of biofill operations") did not get applied correctly, presumably due to substantial similarities between handle_stripe5 and handle_stripe6. This patch moves the chunk of new code from handle_stripe6 (where it isn't needed (yet)) to handle_stripe5. Signed-off-by: Neil Brown <neilb@suse.de> Cc: "Dan Williams" <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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4ae3f847 |
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22-Oct-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: raid5: fix clearing of biofill operations ops_complete_biofill() runs outside of spin_lock(&sh->lock) and clears the 'pending' and 'ack' bits. Since the test_and_ack_op() macro only checks against 'complete' it can get an inconsistent snapshot of pending work. Move the clearing of these bits to handle_stripe5(), under the lock. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Joel Bertrand <joel.bertrand@systella.fr> Signed-off-by: Neil Brown <neilb@suse.de> Cc: Stable <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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fd5d8062 |
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16-Oct-2007 |
Jens Axboe <jens.axboe@oracle.com> |
block: convert blkdev_issue_flush() to use empty barriers Then we can get rid of ->issue_flush_fn() and all the driver private implementations of that. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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6712ecf8 |
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26-Sep-2007 |
NeilBrown <neilb@suse.de> |
Drop 'size' argument from bio_endio and bi_end_io As bi_end_io is only called once when the reqeust is complete, the 'size' argument is now redundant. Remove it. Now there is no need for bio_endio to subtract the size completed from bi_size. So don't do that either. While we are at it, change bi_end_io to return void. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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e4d84909 |
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24-Sep-2007 |
Dan Williams <dan.j.williams@intel.com> |
raid5: fix 2 bugs in ops_complete_biofill 1/ ops_complete_biofill tried to avoid calling handle_stripe since all the state necessary to return read completions is available. However the process of determining whether more read requests are pending requires locking the stripe (to block add_stripe_bio from updating dev->toead). ops_complete_biofill can run in tasklet context, so rather than upgrading all the stripe locks from spin_lock to spin_lock_bh this patch just unconditionally reschedules handle_stripe after completing the read request. 2/ ops_complete_biofill needlessly qualified processing R5_Wantfill with dev->toread. The result being that the 'biofill' pending bit is cleared before handling the pending read-completions on dev->read. R5_Wantfill can be unconditionally handled because the 'biofill' pending bit prevents new R5_Wantfill requests from being seen by ops_run_biofill and ops_complete_biofill. Found-by: Yuri Tikhonov <yur@emcraft.com> [neilb@suse.de: simpler fix for bug 1 than moving code] Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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a2e08551 |
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11-Sep-2007 |
NeilBrown <neilb@suse.de> |
md: fix some bugs with growing raid5/raid6 arrays. The recent changed to raid5 to allow offload of parity calculation etc introduced some bugs in the code for growing (i.e. adding a disk to) raid5 and raid6. This fixes them Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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165125e1 |
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24-Jul-2007 |
Jens Axboe <jens.axboe@oracle.com> |
[BLOCK] Get rid of request_queue_t typedef Some of the code has been gradually transitioned to using the proper struct request_queue, but there's lots left. So do a full sweet of the kernel and get rid of this typedef and replace its uses with the proper type. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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eb0645a8 |
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20-Jul-2007 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: fix kmap_atomic usage in async_memcpy Andrew Morton: [async_memcpy] is very wrong if both ASYNC_TX_KMAP_DST and ASYNC_TX_KMAP_SRC can ever be set. We'll end up using the same kmap slot for both src add dest and we get either corrupted data or a BUG. Evgeniy Polyakov: Btw, shouldn't it always be kmap_atomic() even if flag is not set. That pages are usual one returned by alloc_page(). So fix the usage of kmap_atomic and kill the ASYNC_TX_KMAP_DST and ASYNC_TX_KMAP_SRC flags. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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20c2df83 |
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19-Jul-2007 |
Paul Mundt <lethal@linux-sh.org> |
mm: Remove slab destructors from kmem_cache_create(). Slab destructors were no longer supported after Christoph's c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been BUGs for both slab and slub, and slob never supported them either. This rips out support for the dtor pointer from kmem_cache_create() completely and fixes up every single callsite in the kernel (there were about 224, not including the slab allocator definitions themselves, or the documentation references). Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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f6dff381 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: remove raid5 compute_block and compute_parity5 replaced by raid5_run_ops Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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830ea016 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - request io processing in raid5_run_ops I/O submission requests were already handled outside of the stripe lock in handle_stripe. Now that handle_stripe is only tasked with finding work, this logic belongs in raid5_run_ops. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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f0a50d37 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - add request/completion logic for async expand ops When a stripe is being expanded bulk copying takes place to move the data from the old stripe to the new. Since raid5_run_ops only operates on one stripe at a time these bulk copies are handled in-line under the stripe lock. In the dma offload case we poll for the completion of the operation. After the data has been copied into the new stripe the parity needs to be recalculated across the new disks. We reuse the existing postxor functionality to carry out this calculation. By setting STRIPE_OP_POSTXOR without setting STRIPE_OP_BIODRAIN the completion path in handle stripe can differentiate expand operations from normal write operations. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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b5e98d65 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - add request/completion logic for async read ops When a read bio is attached to the stripe and the corresponding block is marked R5_UPTODATE, then a read (biofill) operation is scheduled to copy the data from the stripe cache to the bio buffer. handle_stripe flags the blocks to be operated on with the R5_Wantfill flag. If new read requests arrive while raid5_run_ops is running they will not be handled until handle_stripe is scheduled to run again. Changelog: * cleanup to_read and to_fill accounting * do not fail reads that have reached the cache Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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e89f8962 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - add request/completion logic for async check ops Check operations are scheduled when the array is being resynced or an explicit 'check/repair' command was sent to the array. Previously check operations would destroy the parity block in the cache such that even if parity turned out to be correct the parity block would be marked !R5_UPTODATE at the completion of the check. When the operation can be carried out by a dma engine the assumption is that it can check parity as a read-only operation. If raid5_run_ops notices that the check was handled by hardware it will preserve the R5_UPTODATE status of the parity disk. When a check operation determines that the parity needs to be repaired we reuse the existing compute block infrastructure to carry out the operation. Repair operations imply an immediate write back of the data, so to differentiate a repair from a normal compute operation the STRIPE_OP_MOD_REPAIR_PD flag is added. Changelog: * remove test_and_set/test_and_clear BUG_ONs, Neil Brown Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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f38e1219 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - add request/completion logic for async compute ops handle_stripe will compute a block when a backing disk has failed, or when it determines it can save a disk read by computing the block from all the other up-to-date blocks. Previously a block would be computed under the lock and subsequent logic in handle_stripe could use the newly up-to-date block. With the raid5_run_ops implementation the compute operation is carried out a later time outside the lock. To preserve the old functionality we take advantage of the dependency chain feature of async_tx to flag the block as R5_Wantcompute and then let other parts of handle_stripe operate on the block as if it were up-to-date. raid5_run_ops guarantees that the block will be ready before it is used in another operation. However, this only works in cases where the compute and the dependent operation are scheduled at the same time. If a previous call to handle_stripe sets the R5_Wantcompute flag there is no facility to pass the async_tx dependency chain across successive calls to raid5_run_ops. The req_compute variable protects against this case. Changelog: * remove the req_compute BUG_ON Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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e33129d8 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: handle_stripe5 - add request/completion logic for async write ops After handle_stripe5 decides whether it wants to perform a read-modify-write, or a reconstruct write it calls handle_write_operations5. A read-modify-write operation will perform an xor subtraction of the blocks marked with the R5_Wantprexor flag, copy the new data into the stripe (biodrain) and perform a postxor operation across all up-to-date blocks to generate the new parity. A reconstruct write is run when all blocks are already up-to-date in the cache so all that is needed is a biodrain and postxor. On the completion path STRIPE_OP_PREXOR will be set if the operation was a read-modify-write. The STRIPE_OP_BIODRAIN flag is used in the completion path to differentiate write-initiated postxor operations versus expansion-initiated postxor operations. Completion of a write triggers i/o to the drives. Changelog: * make the 'rcw' parameter to handle_write_operations5 a simple flag, Neil Brown * remove test_and_set/test_and_clear BUG_ONs, Neil Brown Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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d84e0f10 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: common infrastructure for running operations with raid5_run_ops All the handle_stripe operations that are to be transitioned to use raid5_run_ops need a method to coherently gather work under the stripe-lock and hand that work off to raid5_run_ops. The 'get_stripe_work' routine runs under the lock to read all the bits in sh->ops.pending that do not have the corresponding bit set in sh->ops.ack. This modified 'pending' bitmap is then passed to raid5_run_ops for processing. The transition from 'ack' to 'completion' does not need similar protection as the existing release_stripe infrastructure will guarantee that handle_stripe will run again after a completion bit is set, and handle_stripe can tolerate a sh->ops.completed bit being set while the lock is held. A call to async_tx_issue_pending_all() is added to raid5d to kick the offload engines once all pending stripe operations work has been submitted. This enables batching of the submission and completion of operations. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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91c00924 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
md: raid5_run_ops - run stripe operations outside sh->lock When the raid acceleration work was proposed, Neil laid out the following attack plan: 1/ move the xor and copy operations outside spin_lock(&sh->lock) 2/ find/implement an asynchronous offload api The raid5_run_ops routine uses the asynchronous offload api (async_tx) and the stripe_operations member of a stripe_head to carry out xor+copy operations asynchronously, outside the lock. To perform operations outside the lock a new set of state flags is needed to track new requests, in-flight requests, and completed requests. In this new model handle_stripe is tasked with scanning the stripe_head for work, updating the stripe_operations structure, and finally dropping the lock and calling raid5_run_ops for processing. The following flags outline the requests that handle_stripe can make of raid5_run_ops: STRIPE_OP_BIOFILL - copy data into request buffers to satisfy a read request STRIPE_OP_COMPUTE_BLK - generate a missing block in the cache from the other blocks STRIPE_OP_PREXOR - subtract existing data as part of the read-modify-write process STRIPE_OP_BIODRAIN - copy data out of request buffers to satisfy a write request STRIPE_OP_POSTXOR - recalculate parity for new data that has entered the cache STRIPE_OP_CHECK - verify that the parity is correct STRIPE_OP_IO - submit i/o to the member disks (note this was already performed outside the stripe lock, but it made sense to add it as an operation type The flow is: 1/ handle_stripe sets STRIPE_OP_* in sh->ops.pending 2/ raid5_run_ops reads sh->ops.pending, sets sh->ops.ack, and submits the operation to the async_tx api 3/ async_tx triggers the completion callback routine to set sh->ops.complete and release the stripe 4/ handle_stripe runs again to finish the operation and optionally submit new operations that were previously blocked Note this patch just defines raid5_run_ops, subsequent commits (one per major operation type) modify handle_stripe to take advantage of this routine. Changelog: * removed ops_complete_biodrain in favor of ops_complete_postxor and ops_complete_write. * removed the raid5_run_ops workqueue * call bi_end_io for reads in ops_complete_biofill, saves a call to handle_stripe * explicitly handle the 2-disk raid5 case (xor becomes memcpy), Neil Brown * fix race between async engines and bi_end_io call for reads, Neil Brown * remove unnecessary spin_lock from ops_complete_biofill * remove test_and_set/test_and_clear BUG_ONs, Neil Brown * remove explicit interrupt handling for channel switching, this feature was absorbed (i.e. it is now implicit) by the async_tx api * use return_io in ops_complete_biofill Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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45b4233c |
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09-Jul-2007 |
Dan Williams <dan.j.williams@intel.com> |
raid5: replace custom debug PRINTKs with standard pr_debug Replaces PRINTK with pr_debug, and kills the RAID5_DEBUG definition in favor of the global DEBUG definition. To get local debug messages just add '#define DEBUG' to the top of the file. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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a4456856 |
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09-Jul-2007 |
Dan Williams <dan.j.williams@intel.com> |
raid5: refactor handle_stripe5 and handle_stripe6 (v3) handle_stripe5 and handle_stripe6 have very deep logic paths handling the various states of a stripe_head. By introducing the 'stripe_head_state' and 'r6_state' objects, large portions of the logic can be moved to sub-routines. 'struct stripe_head_state' consumes all of the automatic variables that previously stood alone in handle_stripe5,6. 'struct r6_state' contains the handle_stripe6 specific variables like p_failed and q_failed. One of the nice side effects of the 'stripe_head_state' change is that it allows for further reductions in code duplication between raid5 and raid6. The following new routines are shared between raid5 and raid6: handle_completed_write_requests handle_requests_to_failed_array handle_stripe_expansion Changes: * v2: fixed 'conf->raid_disk-1' for the raid6 'handle_stripe_expansion' path * v3: removed the unused 'dirty' field from struct stripe_head_state * v3: coalesced open coded bi_end_io routines into return_io() Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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9bc89cd8 |
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02-Jan-2007 |
Dan Williams <dan.j.williams@intel.com> |
async_tx: add the async_tx api The async_tx api provides methods for describing a chain of asynchronous bulk memory transfers/transforms with support for inter-transactional dependencies. It is implemented as a dmaengine client that smooths over the details of different hardware offload engine implementations. Code that is written to the api can optimize for asynchronous operation and the api will fit the chain of operations to the available offload resources. I imagine that any piece of ADMA hardware would register with the 'async_*' subsystem, and a call to async_X would be routed as appropriate, or be run in-line. - Neil Brown async_tx exploits the capabilities of struct dma_async_tx_descriptor to provide an api of the following general format: struct dma_async_tx_descriptor * async_<operation>(..., struct dma_async_tx_descriptor *depend_tx, dma_async_tx_callback cb_fn, void *cb_param) { struct dma_chan *chan = async_tx_find_channel(depend_tx, <operation>); struct dma_device *device = chan ? chan->device : NULL; int int_en = cb_fn ? 1 : 0; struct dma_async_tx_descriptor *tx = device ? device->device_prep_dma_<operation>(chan, len, int_en) : NULL; if (tx) { /* run <operation> asynchronously */ ... tx->tx_set_dest(addr, tx, index); ... tx->tx_set_src(addr, tx, index); ... async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param); } else { /* run <operation> synchronously */ ... <operation> ... async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param); } return tx; } async_tx_find_channel() returns a capable channel from its pool. The channel pool is organized as a per-cpu array of channel pointers. The async_tx_rebalance() routine is tasked with managing these arrays. In the uniprocessor case async_tx_rebalance() tries to spread responsibility evenly over channels of similar capabilities. For example if there are two copy+xor channels, one will handle copy operations and the other will handle xor. In the SMP case async_tx_rebalance() attempts to spread the operations evenly over the cpus, e.g. cpu0 gets copy channel0 and xor channel0 while cpu1 gets copy channel 1 and xor channel 1. When a dependency is specified async_tx_find_channel defaults to keeping the operation on the same channel. A xor->copy->xor chain will stay on one channel if it supports both operation types, otherwise the transaction will transition between a copy and a xor resource. Currently the raid5 implementation in the MD raid456 driver has been converted to the async_tx api. A driver for the offload engines on the Intel Xscale series of I/O processors, iop-adma, is provided in a later commit. With the iop-adma driver and async_tx, raid456 is able to offload copy, xor, and xor-zero-sum operations to hardware engines. On iop342 tiobench showed higher throughput for sequential writes (20 - 30% improvement) and sequential reads to a degraded array (40 - 55% improvement). For the other cases performance was roughly equal, +/- a few percentage points. On a x86-smp platform the performance of the async_tx implementation (in synchronous mode) was also +/- a few percentage points of the original implementation. According to 'top' on iop342 CPU utilization drops from ~50% to ~15% during a 'resync' while the speed according to /proc/mdstat doubles from ~25 MB/s to ~50 MB/s. The tiobench command line used for testing was: tiobench --size 2048 --block 4096 --block 131072 --dir /mnt/raid --numruns 5 * iop342 had 1GB of memory available Details: * if CONFIG_DMA_ENGINE=n the asynchronous path is compiled away by making async_tx_find_channel a static inline routine that always returns NULL * when a callback is specified for a given transaction an interrupt will fire at operation completion time and the callback will occur in a tasklet. if the the channel does not support interrupts then a live polling wait will be performed * the api is written as a dmaengine client that requests all available channels * In support of dependencies the api implicitly schedules channel-switch interrupts. The interrupt triggers the cleanup tasklet which causes pending operations to be scheduled on the next channel * Xor engines treat an xor destination address differently than a software xor routine. To the software routine the destination address is an implied source, whereas engines treat it as a write-only destination. This patch modifies the xor_blocks routine to take a an explicit destination address to mirror the hardware. Changelog: * fixed a leftover debug print * don't allow callbacks in async_interrupt_cond * fixed xor_block changes * fixed usage of ASYNC_TX_XOR_DROP_DEST * drop dma mapping methods, suggested by Chris Leech * printk warning fixups from Andrew Morton * don't use inline in C files, Adrian Bunk * select the API when MD is enabled * BUG_ON xor source counts <= 1 * implicitly handle hardware concerns like channel switching and interrupts, Neil Brown * remove the per operation type list, and distribute operation capabilities evenly amongst the available channels * simplify async_tx_find_channel to optimize the fast path * introduce the channel_table_initialized flag to prevent early calls to the api * reorganize the code to mimic crypto * include mm.h as not all archs include it in dma-mapping.h * make the Kconfig options non-user visible, Adrian Bunk * move async_tx under crypto since it is meant as 'core' functionality, and the two may share algorithms in the future * move large inline functions into c files * checkpatch.pl fixes * gpl v2 only correction Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
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685784aa |
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09-Jul-2007 |
Dan Williams <dan.j.williams@intel.com> |
xor: make 'xor_blocks' a library routine for use with async_tx The async_tx api tries to use a dma engine for an operation, but will fall back to an optimized software routine otherwise. Xor support is implemented using the raid5 xor routines. For organizational purposes this routine is moved to a common area. The following fixes are also made: * rename xor_block => xor_blocks, suggested by Adrian Bunk * ensure that xor.o initializes before md.o in the built-in case * checkpatch.pl fixes * mark calibrate_xor_blocks __init, Adrian Bunk Cc: Adrian Bunk <bunk@stusta.de> Cc: NeilBrown <neilb@suse.de> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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44ce6294 |
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09-May-2007 |
Linus Torvalds <torvalds@woody.linux-foundation.org> |
Revert "md: improve partition detection in md array" This reverts commit 5b479c91da90eef605f851508744bfe8269591a0. Quoth Neil Brown: "It causes an oops when auto-detecting raid arrays, and it doesn't seem easy to fix. The array may not be 'open' when do_md_run is called, so bdev->bd_disk might be NULL, so bd_set_size can oops. This whole approach of opening an md device before it has been assembled just seems to get more and more painful. I think I'm going to have to come up with something clever to provide both backward comparability with usage expectation, and sane integration into the rest of the kernel." Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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5b479c91 |
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09-May-2007 |
NeilBrown <neilb@suse.de> |
md: improve partition detection in md array md currently uses ->media_changed to make sure rescan_partitions is call on md array after they are assembled. However that doesn't happen until the array is opened, which is later than some people would like. So use blkdev_ioctl to do the rescan immediately that the array has been assembled. This means we can remove all the ->change infrastructure as it was only used to trigger a partition rescan. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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42b9bebe |
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09-May-2007 |
NeilBrown <neilb@suse.de> |
md: remove the slash from the name of a kmem_cache used by raid5 SLUB doesn't like slashes as it wants to use the cache name as the name of a directory (or symlink) in sysfs. Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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5e55e2f5 |
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26-Mar-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: convert compile time warnings into runtime warnings ... still not sure why we need this .... Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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041ae52e |
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26-Mar-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: clear the congested_fn when stopping a raid5 If this mddev and queue got reused for another array that doesn't register a congested_fn, this function would get called incorretly. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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3d37890b |
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26-Mar-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: allow raid4 arrays to be reshaped All that is missing the the function pointers in raid4_pers. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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6d3baf2e |
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05-Mar-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix for raid6 reshape Recent patch for raid6 reshape had a change missing that showed up in subsequent review. Many places in the raid5 code used "conf->raid_disks-1" to mean "number of data disks". With raid6 that had to be changed to "conf->raid_disk - conf->max_degraded" or similar. One place was missed. This bug means that if a raid6 reshape were aborted in the middle the recorded position would be wrong. On restart it would either fail (as the position wasn't on an appropriate boundary) or would leave a section of the array unreshaped, causing data corruption. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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f416885e |
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28-Feb-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: add support for reshape of a raid6 i.e. one or more drives can be added and the array will re-stripe while on-line. Most of the interesting work was already done for raid5. This just extends it to raid6. mdadm newer than 2.6 is needed for complete safety, however any version of mdadm which support raid5 reshape will do a good enough job in almost all cases (an 'echo repair > /sys/block/mdX/md/sync_action' is recommended after a reshape that was aborted and had to be restarted with an such a version of mdadm). Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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b4c4c7b8 |
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28-Feb-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: restart a (raid5) reshape that has been aborted due to a read/write error An error always aborts any resync/recovery/reshape on the understanding that it will immediately be restarted if that still makes sense. However a reshape currently doesn't get restarted. With this patch it does. To avoid restarting when it is not possible to do work, we call into the personality to check that a reshape is ok, and strengthen raid5_check_reshape to fail if there are too many failed devices. We also break some code out into a separate function: remove_and_add_spares as the indent level for that code was getting crazy. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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387bb173 |
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08-Feb-2007 |
Neil Brown <neilb@suse.de> |
[PATCH] md: fix various bugs with aligned reads in RAID5 It is possible for raid5 to be sent a bio that is too big for an underlying device. So if it is a READ that we pass stright down to a device, it will fail and confuse RAID5. So in 'chunk_aligned_read' we check that the bio fits within the parameters for the target device and if it doesn't fit, fall back on reading through the stripe cache and making lots of one-page requests. Note that this is the earliest time we can check against the device because earlier we don't have a lock on the device, so it could change underneath us. Also, the code for handling a retry through the cache when a read fails has not been tested and was badly broken. This patch fixes that code. Signed-off-by: Neil Brown <neilb@suse.de> Cc: "Kai" <epimetreus@fastmail.fm> Cc: <stable@suse.de> Cc: <org@suse.de> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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c20086de |
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26-Jan-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: remove unnecessary printk when raid5 gets an unaligned read. raid5_mergeable_bvec tries to ensure that raid5 never sees a read request that does not fit within just one chunk. However as we must always accept a single-page read, that is not always possible. So when "in_chunk_boundary" fails, it might be unusual, but it is not a problem and printing a message every time is a bad idea. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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2a2275d6 |
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26-Jan-2007 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix potential memalloc deadlock in md If a GFP_KERNEL allocation is attempted in md while the mddev_lock is held, it is possible for a deadlock to eventuate. This happens if the array was marked 'clean', and the memalloc triggers a write-out to the md device. For the writeout to succeed, the array must be marked 'dirty', and that requires getting the mddev_lock. So, before attempting a GFP_KERNEL allocation while holding the lock, make sure the array is marked 'dirty' (unless it is currently read-only). Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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802ba064 |
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13-Dec-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Don't assume that READ==0 and WRITE==1 - use the names explicitly Thanks Jens for alerting me to this. Cc: Jens Axboe <jens.axboe@oracle.com> Cc: <raziebe@gmail.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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c2b00852 |
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10-Dec-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: return a non-zero error to bi_end_io as appropriate in raid5 Currently raid5 depends on clearing the BIO_UPTODATE flag to signal an error to higher levels. While this should be sufficient, it is safer to explicitly set the error code as well - less room for confusion. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b8c6b645 |
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10-Dec-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: remove some old ifdefed-out code from raid5.c There are some vestiges of old code that was used for bypassing the stripe cache on reads in raid5.c. This was never updated after the change from buffer_heads to bios, but was left as a reminder. That functionality has nowe been implemented in a completely different way, so the old code can go. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b875e531 |
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10-Dec-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix innocuous bug in raid6 stripe_to_pdidx stripe_to_pdidx finds the index of the parity disk for a given stripe. It assumes raid5 in that it uses "disks-1" to determine the number of data disks. This is incorrect for raid6 but fortunately the two usages cancel each other out. The only way that 'data_disks' affects the calculation of pd_idx in raid5_compute_sector is when it is divided into the sector number. But as that sector number is calculated by multiplying in the wrong value of 'data_disks' the division produces the right value. So it is innocuous but needs to be fixed. Also change the calculation of raid_disks in compute_blocknr to make it more obviously correct (it seems at first to always use disks-1 too). Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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52488615 |
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10-Dec-2006 |
Raz Ben-Jehuda(caro) <raziebe@gmail.com> |
[PATCH] md: enable bypassing cache for reads Call the chunk_aligned_read where appropriate. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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46031f9a |
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10-Dec-2006 |
Raz Ben-Jehuda(caro) <raziebe@gmail.com> |
[PATCH] md: allow reads that have bypassed the cache to be retried on failure If a bypass-the-cache read fails, we simply try again through the cache. If it fails again it will trigger normal recovery precedures. update 1: From: NeilBrown <neilb@suse.de> 1/ chunk_aligned_read and retry_aligned_read assume that data_disks == raid_disks - 1 which is not true for raid6. So when an aligned read request bypasses the cache, we can get the wrong data. 2/ The cloned bio is being used-after-free in raid5_align_endio (to test BIO_UPTODATE). 3/ We forgot to add rdev->data_offset when submitting a bio for aligned-read 4/ clone_bio calls blk_recount_segments and then we change bi_bdev, so we need to invalidate the segment counts. 5/ We don't de-reference the rdev when the read completes. This means we need to record the rdev to so it is still available in the end_io routine. Fortunately bi_next in the original bio is unused at this point so we can stuff it in there. 6/ We leak a cloned bio if the target rdev is not usable. From: NeilBrown <neilb@suse.de> update 2: 1/ When aligned requests fail (read error) they need to be retried via the normal method (stripe cache). As we cannot be sure that we can process a single read in one go (we may not be able to allocate all the stripes needed) we store a bio-being-retried and a list of bioes-that-still-need-to-be-retried. When find a bio that needs to be retried, we should add it to the list, not to single-bio... 2/ We were never incrementing 'scnt' when resubmitting failed aligned requests. [akpm@osdl.org: build fix] Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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f679623f |
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10-Dec-2006 |
Raz Ben-Jehuda(caro) <raziebe@gmail.com> |
[PATCH] md: handle bypassing the read cache (assuming nothing fails) Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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23032a0e |
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10-Dec-2006 |
Raz Ben-Jehuda(caro) <raziebe@gmail.com> |
[PATCH] md: define raid5_mergeable_bvec This will encourage read request to be on only one device, so we will often be able to bypass the cache for read requests. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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e18b890b |
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06-Dec-2006 |
Christoph Lameter <clameter@sgi.com> |
[PATCH] slab: remove kmem_cache_t Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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0692c6b1 |
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08-Nov-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix sizing problem with raid5-reshape and CONFIG_LBD=n I forgot to has the size-in-blocks to (loff_t) before shifting up to a size-in-bytes. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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52e5f9d1 |
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03-Oct-2006 |
Eric Sesterhenn <snakebyte@gmx.de> |
BUG_ON cleanup for drivers/md/ This changes two if() BUG(); usages to BUG_ON(); so people can disable it safely. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
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f022b2fd |
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03-Oct-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: add a ->congested_fn function for raid5/6 This is very different from other raid levels and all requests go through a 'stripe cache', and it has congestion management already. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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c04be0aa |
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03-Oct-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Improve locking around error handling The error handling routines don't use proper locking, and so two concurrent errors could trigger a problem. So: - use test-and-set and test-and-clear to synchonise the In_sync bits with the ->degraded count - use the spinlock to protect updates to the degraded count (could use an atomic_t but that would be a bigger change in code, and isn't really justified) - remove un-necessary locking in raid5 Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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2d2063ce |
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03-Oct-2006 |
Coywolf Qi Hunt <qiyong@freeforge.net> |
[PATCH] md: remove unnecessary variable x in stripe_to_pdidx() Signed-off-by: Coywolf Qi Hunt <qiyong@freeforge.net> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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02c2de8c |
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03-Oct-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: remove the working_disks and failed_disks from raid5 state data. They are not needed. conf->failed_disks is the same as mddev->degraded and conf->working_disks is conf->raid_disks - mddev->degraded. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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850b2b42 |
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03-Oct-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: replace magic numbers in sb_dirty with well defined bit flags Instead of magic numbers (0,1,2,3) in sb_dirty, we have some flags instead: MD_CHANGE_DEVS Some device state has changed requiring superblock update on all devices. MD_CHANGE_CLEAN The array has transitions from 'clean' to 'dirty' or back, requiring a superblock update on active devices, but possibly not on spares MD_CHANGE_PENDING A superblock update is underway. We wait for an update to complete by waiting for all flags to be clear. A flag can be set at any time, even during an update, without risk that the change will be lost. Stop exporting md_update_sb - isn't needed. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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d6950432 |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: include sector number in messages about corrected read errors This is generally useful, but particularly helps see if it is the same sector that always needs correcting, or different ones. [akpm@osdl.org: fix printk warnings] Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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ae3c20cc |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix some small races in bitmap plugging in raid5 The comment gives more details, but I didn't quite have the sequencing write, so there was room for races to leave bits unset in the on-disk bitmap for short periods of time. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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7c785b7a |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix a plug/unplug race in raid5 When a device is unplugged, requests are moved from one or two (depending on whether a bitmap is in use) queues to the main request queue. So whenever requests are put on either of those queues, we should make sure the raid5 array is 'plugged'. However we don't. We currently plug the raid5 queue just before putting requests on queues, so there is room for a race. If something unplugs the queue at just the wrong time, requests will be left on the queue and nothing will want to unplug them. Normally something else will plug and unplug the queue fairly soon, but there is a risk that nothing will. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
ff4e8d9a |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix resync speed calculation for restarted resyncs We introduced 'io_sectors' recently so we could count the sectors that causes io during resync separate from sectors which didn't cause IO - there can be a difference if a bitmap is being used to accelerate resync. However when a speed is reported, we find the number of sectors processed recently by subtracting an oldish io_sectors count from a current 'curr_resync' count. This is wrong because curr_resync counts all sectors, not just io sectors. So, add a field to mddev to store the curren io_sectors separately from curr_resync, and use that in the calculations. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
0b8c9de0 |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: delay starting md threads until array is completely setup When an array is started we start one or two threads (two if there is a reshape or recovery that needs to be completed). We currently start these *before* the array is completely set up and in particular before queue->queuedata is set. If the thread actually starts very quickly on another CPU, we can end up dereferencing queue->queuedata and oops. This patch also makes sure we don't try to start a recovery if a reshape is being restarted. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
f4370781 |
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10-Jul-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: possible fix for unplug problem I have reports of a problem with raid5 which turns out to be because the raid5 device gets stuck in a 'plugged' state. This shouldn't be able to happen as 3msec after it gets plugged it should get unplugged. However it happens none-the-less. This patch fixes the problem and is a reasonable thing to do, though it might hurt performance slightly in some cases. Until I can find the real problem, we should probably have this workaround in place. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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6ab3d562 |
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30-Jun-2006 |
Jörn Engel <joern@wohnheim.fh-wedel.de> |
Remove obsolete #include <linux/config.h> Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
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#
cfb9e32f |
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29-Jun-2006 |
Adrian Bunk <bunk@stusta.de> |
[PATCH] drivers/md/raid5.c: remove an unused variable Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
3285edf1 |
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26-Jun-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Fix bug that stops raid5 resync from happening As data_disks is *less* than raid_disks, the current test here is obviously wrong. And as the difference is already available in conf->max_degraded, it makes much more sense to use that. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
52c03291 |
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26-Jun-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: split reshape portion of raid5 sync_request into a separate function ... as raid5 sync_request is WAY too big. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
5fd6c1dc |
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26-Jun-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: allow checkpoint of recovery with version-1 superblock For a while we have had checkpointing of resync. The version-1 superblock allows recovery to be checkpointed as well, and this patch implements that. Due to early carelessness we need to add a feature flag to signal that the recovery_offset field is in use, otherwise older kernels would assume that a partially recovered array is in fact fully recovered. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
16a53ecc |
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26-Jun-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: merge raid5 and raid6 code There is a lot of commonality between raid5.c and raid6main.c. This patches merges both into one module called raid456. This saves a lot of code, and paves the way for online raid5->raid6 migrations. There is still duplication, e.g. between handle_stripe5 and handle_stripe6. This will probably be cleaned up later. Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
8932c2e0 |
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26-Jun-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: remove arbitrary limit on chunk size The largest chunk size the code can support without substantial surgery is 2^30 bytes, so make that the limit instead of an arbitrary 4Meg. Some day, the 'chunksize' should change to a sector-shift instead of a byte-count. Then no limit would be needed. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
78bafebd |
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02-Apr-2006 |
Eric Sesterhenn <snakebyte@gmx.de> |
BUG_ON() Conversion in md/raid5.c this changes if() BUG(); constructs to BUG_ON() which is cleaner and can better optimized away Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
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#
f6344757 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Remove bi_end_io call out from under a spinlock raid5 overloads bi_phys_segments to count the number of blocks that the request was broken in to so that it knows when the bio is completely handled. Accessing this must always be done under a spinlock. In one case we also call bi_end_io under that spinlock, which probably isn't ideal as bi_end_io could be expensive (even though it isn't allowed to sleep). So we reducde the range of the spinlock to just accessing bi_phys_segments. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
b3b46be3 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Remove some stray semi-colons after functions called in macro.. wait_event_lock_irq puts a ';' after its usage of the 4th arg, so we don't need to. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
df8e7f76 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Improve comments about locking situation in raid5 make_request Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
e464eafd |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Support suspending of IO to regions of an md array This allows user-space to access data safely. This is needed for raid5 reshape as user-space needs to take a backup of the first few stripes before allowing reshape to commence. It will also be useful in cluster-aware raid1 configurations so that all cluster members can leave a section of the array untouched while a resync/recovery happens. A 'start' and 'end' of the suspended range are written to 2 sysfs attributes. Note that only one range can be suspended at a time. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
63c70c4f |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Split reshape handler in check_reshape and start_reshape check_reshape checks validity and does things that can be done instantly - like adding devices to raid1. start_reshape initiates a restriping process to convert the whole array. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
b578d55f |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Only checkpoint expansion progress occasionally Instead of checkpointing at each stripe, only checkpoint when a new write would overwrite uncheckpointed data. Block any write to the uncheckpointed area. Arbitrarily checkpoint at least every 3Meg. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
f6705578 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Checkpoint and allow restart of raid5 reshape We allow the superblock to record an 'old' and a 'new' geometry, and a position where any conversion is up to. The geometry allows for changing chunksize, layout and level as well as number of devices. When using verion-0.90 superblock, we convert the version to 0.91 while the conversion is happening so that an old kernel will refuse the assemble the array. For version-1, we use a feature bit for the same effect. When starting an array we check for an incomplete reshape and restart the reshape process if needed. If the reshape stopped at an awkward time (like when updating the first stripe) we refuse to assemble the array, and let user-space worry about it. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
29269553 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Final stages of raid5 expand code This patch adds raid5_reshape and end_reshape which will start and finish the reshape processes. raid5_reshape is only enabled in CONFIG_MD_RAID5_RESHAPE is set, to discourage accidental use. Read the 'help' for the CONFIG_MD_RAID5_RESHAPE entry. and Make sure that you have backups, just in case. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
ccfcc3c1 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Core of raid5 resize process This patch provides the core of the resize/expand process. sync_request notices if a 'reshape' is happening and acts accordingly. It allocated new stripe_heads for the next chunk-wide-stripe in the target geometry, marking them STRIPE_EXPANDING. Then it finds which stripe heads in the old geometry can provide data needed by these and marks them STRIPE_EXPAND_SOURCE. This causes stripe_handle to read all blocks on those stripes. Once all blocks on a STRIPE_EXPAND_SOURCE stripe_head are read, any that are needed are copied into the corresponding STRIPE_EXPANDING stripe_head. Once a STRIPE_EXPANDING stripe_head is full, it is marks STRIPE_EXPAND_READY and then is written out and released. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
7ecaa1e6 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Infrastructure to allow normal IO to continue while array is expanding We need to allow that different stripes are of different effective sizes, and use the appropriate size. Also, when a stripe is being expanded, we must block any IO attempts until the stripe is stable again. Key elements in this change are: - each stripe_head gets a 'disk' field which is part of the key, thus there can sometimes be two stripe heads of the same area of the array, but covering different numbers of devices. One of these will be marked STRIPE_EXPANDING and so won't accept new requests. - conf->expand_progress tracks how the expansion is progressing and is used to determine whether the target part of the array has been expanded yet or not. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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ad01c9e3 |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Allow stripes to be expanded in preparation for expanding an array Before a RAID-5 can be expanded, we need to be able to expand the stripe-cache data structure. This requires allocating new stripes in a new kmem_cache. If this succeeds, we copy cache pages over and release the old stripes and kmem_cache. We then allocate new pages. If that fails, we leave the stripe cache at it's new size. It isn't worth the effort to shrink it back again. Unfortuanately this means we need two kmem_cache names as we, for a short period of time, we have two kmem_caches. So they are raid5/%s and raid5/%s-alt Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b55e6bfc |
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27-Mar-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Split disks array out of raid5 conf structure so it is easier to grow The remainder of this batch implements raid5 reshaping. Currently the only shape change that is supported is added a device, but it is envisioned that changing the chunksize and layout will also be supported, as well as changing the level (e.g. 1->5, 5->6). The reshape process naturally has to move all of the data in the array, and so should be used with caution. It is believed to work, and some testing does support this, but wider testing would be great for increasing my confidence. You will need a version of mdadm newer than 2.3.1 to make use of raid5 growth. This is because mdadm need to take a copy of a 'critical section' at the start of the array incase there is a crash at an awkward moment. On restart, mdadm will restore the critical section and allow reshape to continue. I hope to release a 2.4-pre by early next week - it still needs a little more polishing. This patch: Previously the array of disk information was included in the raid5 'conf' structure which was allocated to an appropriate size. This makes it awkward to change the size of that array. So we split it off into a separate kmalloced array which will require a little extra indexing, but is much easier to grow. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
29fc7e3e |
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03-Feb-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: Assorted little md fixes - version-1 superblock + The default_bitmap_offset is in sectors, not bytes. + the 'size' field in the superblock is in sectors, not KB - raid0_run should return a negative number on error, not '1' - raid10_read_balance should not return a valid 'disk' number if ->rdev turned out to be NULL - kmem_cache_destroy doesn't like being passed a NULL. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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858119e1 |
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14-Jan-2006 |
Arjan van de Ven <arjan@infradead.org> |
[PATCH] Unlinline a bunch of other functions Remove the "inline" keyword from a bunch of big functions in the kernel with the goal of shrinking it by 30kb to 40kb Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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4dbcdc75 |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: count corrected read errors per drive Store this total in superblock (As appropriate), and make it available to userspace via sysfs. Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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d9d166c2 |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: allow array level to be set textually via sysfs Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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2604b703 |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: remove personality numbering from md md supports multiple different RAID level, each being implemented by a 'personality' (which is often in a separate module). These personalities have fairly artificial 'numbers'. The numbers are use to: 1- provide an index into an array where the various personalities are recorded 2- identify the module (via an alias) which implements are particular personality. Neither of these uses really justify the existence of personality numbers. The array can be replaced by a linked list which is searched (array lookup only happens very rarely). Module identification can be done using an alias based on level rather than 'personality' number. The current 'raid5' modules support two level (4 and 5) but only one personality. This slight awkwardness (which was handled in the mapping from level to personality) can be better handled by allowing raid5 to register 2 personalities. With this change in place, the core md module does not need to have an exhaustive list of all possible personalities, so other personalities can be added independently. This patch also moves the check for chunksize being non-zero into the ->run routines for the personalities that need it, rather than having it in core-md. This has a side effect of allowing 'faulty' and 'linear' not to have a chunk-size set. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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fccddba0 |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: tidy up raid5/6 hash table code - replace open-coded hash chain with hlist macros - Fix hash-table size at one page - it is already quite generous, so there will never be a need to use multiple pages, so no need for __get_free_pages No functional change. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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9ffae0cf |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: convert md to use kzalloc throughout Replace multiple kmalloc/memset pairs with kzalloc calls. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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2d1f3b5d |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: clean up 'page' related names in md Substitute: page_cache_get -> get_page page_cache_release -> put_page PAGE_CACHE_SHIFT -> PAGE_SHIFT PAGE_CACHE_SIZE -> PAGE_SIZE PAGE_CACHE_MASK -> PAGE_MASK __free_page -> put_page because we aren't using the page cache, we are just using pages. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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9910f16a |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix up some rdev rcu locking in raid5/6 There is this "FIXME" comment with a typo in it!! that been annoying me for days, so I just had to remove it. conf->disks[i].rdev should only be accessed if - we know we hold a reference or - the mddev->reconfig_sem is down or - we have a rcu_readlock handle_stripe was referencing rdev in three places without any of these. For the first two, get an rcu_readlock. For the last, the same access (md_sync_acct call) is made a little later after the rdev has been claimed under and rcu_readlock, if R5_Syncio is set. So just use that access... However R5_Syncio isn't really needed as the 'syncing' variable contains the same information. So use that instead. Issues, comment, and fix are identical in raid5 and raid6. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b15c2e57 |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: move bitmap_create to after md array has been initialised This is important because bitmap_create uses mddev->resync_max_sectors and that doesn't have a valid value until after the array has been initialised (with pers->run()). [It doesn't make a difference for current personalities that support bitmaps, but will make a difference for raid10] This has the added advantage of meaning with can move the thread->timeout manipulation inside the bitmap.c code instead of sprinkling identical code throughout all personalities. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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6ff8d8ec |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: allow dirty raid[456] arrays to be started at boot See patch to md.txt for more details Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
14f8d26b |
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06-Jan-2006 |
NeilBrown <neilb@suse.de> |
[PATCH] md: small cleanups for raid5 Resync code: A test that isn't needed, a 'compute_block' that makes more sense elsewhere (And then doesn't need a test), a couple of BUG_ONs to confirm the change makes sense. Printks: A few were missing KERN_* Also fix a typo in a comment.. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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5036805b |
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12-Dec-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: use correct size of raid5 stripe cache when measuring how full it is The raid5 stripe cache was recently changed from fixed size (NR_STRIPES) to variable size (conf->max_nr_stripes). However there are two places that still use the constant and as a result, reducing the size of the stripe cache can result in a deadlock. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
700e432d |
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28-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix locking problem in r5/r6 bitmap_unplug actually writes data (bits) to storage, so we shouldn't be holding a spinlock... Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
96de1e66 |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix some locking and module refcounting issues with md's use of sysfs 1/ I really should be using the __ATTR macros for defining attributes, so that the .owner field get set properly, otherwise modules can be removed while sysfs files are open. This also involves some name changes of _show routines. 2/ Always lock the mddev (against reconfiguration) for all sysfs attribute access. This easily avoid certain races and is completely consistant with other interfaces (ioctl and /proc/mdstat both always lock against reconfiguration). 3/ raid5 attributes must check that the 'conf' structure actually exists (the array could have been stopped while an attribute file was open). 4/ A missing 'kfree' from when the raid5_conf_t was converted to have a kobject embedded, and then converted back again. Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
3855ad9f |
|
08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: make sure a user-request sync of raid5 ignores intent bitmap A sync of raid5 usually ignore blocks which the bitmap says are in-sync. But a user-request check or repair should not ignore these. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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#
b2d444d7 |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: convert 'faulty' and 'in_sync' fields to bits in 'flags' field This has the advantage of removing the confusion caused by 'rdev_t' and 'mddev_t' both having 'in_sync' fields. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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ba22dcbf |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: improvements to raid5 handling of read errors Two refinements to the 'attempt-overwrite-on-read-error' mechanism. 1/ If the array is read-only, don't attempt an over-write. 2/ If there are more than max_nr_stripes read errors on a device with no success, fail the drive. This will make sure a dead drive will be eventually kicked even when we aren't trying to rewrite (which would normally kick a dead drive more quickly. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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007583c9 |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: change raid5 sysfs attribute to not create a new directory There isn't really a need for raid5 attributes to be an a subdirectory, so this patch moves them from /sys/block/mdX/md/raid5/attribute to /sys/block/mdX/md/attribute This suggests that all md personalities should co-operate about namespace usage, but that shouldn't be a problem. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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9c791977 |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: fix ref-counting problems with kobjects in md Thanks Greg. Cc: Greg KH <greg@kroah.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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d6065f7b |
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08-Nov-2005 |
Suzanne Wood <suzannew@cs.pdx.edu> |
[PATCH] md: provide proper rcu_dereference / rcu_assign_pointer annotations in md Acked-by: <paulmck@us.ibm.com> Signed-off-by: Suzanne Wood <suzannew@cs.pdx.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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9d88883e |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: teach raid5 the difference between 'check' and 'repair'. With this, raid5 can be asked to check parity without repairing it. It also keeps a count of the number of incorrect parity blocks found (mismatches) and reports them through sysfs. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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3f294f4f |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: add kobject/sysfs support to raid5 /sys/block/mdX/md/raid5/ contains raid5-related attributes. Currently stripe_cache_size is number of entries in stripe cache, and is settable. stripe_cache_active is number of active entries, and in only readable. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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4e5314b5 |
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08-Nov-2005 |
NeilBrown <neilb@suse.de> |
[PATCH] md: better handling of readerrors with raid5. This patch changes the behaviour of raid5 when it gets a read error. Instead of just failing the device, it tried to find out what should have been there, and writes it over the bad block. For some media-errors, this has a reasonable chance of fixing the error. If the write succeeds, and a subsequent read succeeds as well, raid5 decided the address is OK and conitnues. Instead of failing a drive on read-error, we attempt to re-write the block, and then re-read. If that all works, we allow the device to remain in the array. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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66c006a5 |
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07-Nov-2005 |
Nishanth Aravamudan <nacc@us.ibm.com> |
[PATCH] drivers/md: fix-up schedule_timeout() usage Use schedule_timeout_interruptible() instead of set_current_state()/schedule_timeout() to reduce kernel size. Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Cc: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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a362357b |
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01-Nov-2005 |
Jens Axboe <axboe@suse.de> |
[BLOCK] Unify the seperate read/write io stat fields into arrays Instead of having ->read_sectors and ->write_sectors, combine the two into ->sectors[2] and similar for the other fields. This saves a branch several places in the io path, since we don't have to care for what the actual io direction is. On my x86-64 box, that's 200 bytes less text in just the core (not counting the various drivers). Signed-off-by: Jens Axboe <axboe@suse.de>
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72626685 |
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09-Sep-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: add write-intent-bitmap support to raid5 Most awkward part of this is delaying write requests until bitmap updates have been flushed. To achieve this, we have a sequence number (seq_flush) which is incremented each time the raid5 is unplugged. If the raid thread notices that this has changed, it flushes bitmap changes, and assigned the value of seq_flush to seq_write. When a write request arrives, it is given the number from seq_write, and that write request may not complete until seq_flush is larger than the saved seq number. We have a new queue for storing stripes which are waiting for a bitmap flush and an extra flag for stripes to record if the write was 'degraded' and so should not clear the a bit in the bitmap. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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e5dcdd80 |
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09-Sep-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: fail IO request to md that require a barrier. md does not yet support BIO_RW_BARRIER, so be honest about it and fail (-EOPNOTSUPP) any such requests. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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b1581566 |
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31-Jul-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: make sure raid5/raid6 resync uses correct 'max_sectors' The default resync_max_sector is set to "mddev->size << 1". If the raid-personality-module updates mddev->size, it must update resync_max_sectors too. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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4b5c7ae8 |
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27-Jul-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: when resizing an array, we need to update resync_max_sectors as well as size Without this, and attempt to 'grow' an array will claim to have synced the extra part without actually having done anything. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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3d310eb7 |
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21-Jun-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: fix deadlock due to md thread processing delayed requests. Before completing a 'write' the md superblock might need to be updated. This is best done by the md_thread. The current code schedules this up and queues the write request for later handling by the md_thread. However some personalities (Raid5/raid6) will deadlock if the md_thread tries to submit requests to its own array. So this patch changes things so the processes submitting the request waits for the superblock to be written and then submits the request itself. This fixes a recently-created deadlock in raid5/raid6 Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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57afd89f |
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21-Jun-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: improve the interface to sync_request 1/ change the return value (which is number-of-sectors synced) from 'int' to 'sector_t'. The number of sectors is usually easily small enough to fit in an int, but if resync needs to abort, it may want to return the total number of remaining sectors, which could be large. Also errors cannot be returned as negative numbers now, so use 0 instead 2/ Add a 'skipped' return parameter to allow the array to report that it skipped the sectors. This allows md to take this into account in the speed calculations. Currently there is no important skipping, but the bitmap-based-resync that is coming will use this. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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06d91a5f |
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21-Jun-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: improve locking on 'safemode' and move superblock writes When md marks the superblock dirty before a write, it calls generic_make_request (to write the superblock) from within generic_make_request (to write the first dirty block), which could cause problems later. With this patch, the superblock write is always done by the helper thread, and write request are delayed until that write completes. Also, the locking around marking the array dirty and writing the superblock is improved to avoid possible races. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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fca4d848 |
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21-Jun-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: merge md_enter_safemode into md_check_recovery md_enter_safemode checks if it is time to mark the md superblock as 'clean'. i.e. if all writes have completed and a suitable delay has passed. This is currently called from md_handle_safemode which in-turn is called (almost) every time md_check_recovery is called, and from the end of md_do_sync which causes the mddev->thread to run, which will always call md_check_recovery as well. So it doesn't need to be a separate function and fits quite well into md_check_recovery. The "almost" is because multipathd calls md_check_recovery but not md_handle_safemode. This is OK because the code from md_enter_safemode is a no-op if mddev->safemode == 0, which it always is for a multipathd (providing we don't allow it to be set to 2 on a signal...) Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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7a5febe9 |
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16-May-2005 |
NeilBrown <neilb@cse.unsw.edu.au> |
[PATCH] md: set the unplug_fn and issue_flush_fn for md devices *after* committed to creation We we set the too early, they may still be in place and possibly get called even though the array didn't get set up properly. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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fbd568a3e |
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01-May-2005 |
Paul E. McKenney <paulmck@kernel.org> |
[PATCH] Change synchronize_kernel to _rcu and _sched This patch changes calls to synchronize_kernel(), deprecated in the earlier "Deprecate synchronize_kernel, GPL replacement" patch to instead call the new synchronize_rcu() and synchronize_sched() APIs. Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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1da177e4 |
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16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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