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d4830012 |
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05-Jun-2023 |
Li Lingfeng <lilingfeng3@huawei.com> |
dm thin metadata: Fix ABBA deadlock by resetting dm_bufio_client As described in commit 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata"), ABBA deadlocks will be triggered because shrinker_rwsem currently needs to held by dm_pool_abort_metadata() as a side-effect of thin-pool metadata operation failure. The following three problem scenarios have been noticed: 1) Described by commit 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata") 2) shrinker_rwsem and throttle->lock P1(drop cache) P2(kworker) drop_caches_sysctl_handler drop_slab shrink_slab down_read(&shrinker_rwsem) - LOCK A do_shrink_slab super_cache_scan prune_icache_sb dispose_list evict ext4_evict_inode ext4_clear_inode ext4_discard_preallocations ext4_mb_load_buddy_gfp ext4_mb_init_cache ext4_wait_block_bitmap __ext4_error ext4_handle_error ext4_commit_super ... dm_submit_bio do_worker throttle_work_update down_write(&t->lock) -- LOCK B process_deferred_bios commit metadata_operation_failed dm_pool_abort_metadata dm_block_manager_create dm_bufio_client_create register_shrinker down_write(&shrinker_rwsem) -- LOCK A thin_map thin_bio_map thin_defer_bio_with_throttle throttle_lock down_read(&t->lock) - LOCK B 3) shrinker_rwsem and wait_on_buffer P1(drop cache) P2(kworker) drop_caches_sysctl_handler drop_slab shrink_slab down_read(&shrinker_rwsem) - LOCK A do_shrink_slab ... ext4_wait_block_bitmap __ext4_error ext4_handle_error jbd2_journal_abort jbd2_journal_update_sb_errno jbd2_write_superblock submit_bh // LOCK B // RELEASE B do_worker throttle_work_update down_write(&t->lock) - LOCK B process_deferred_bios process_bio commit metadata_operation_failed dm_pool_abort_metadata dm_block_manager_create dm_bufio_client_create register_shrinker register_shrinker_prepared down_write(&shrinker_rwsem) - LOCK A bio_endio wait_on_buffer __wait_on_buffer Fix these by resetting dm_bufio_client without holding shrinker_rwsem. Fixes: 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata") Cc: stable@vger.kernel.org Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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47a7c01c |
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09-Jun-2023 |
Qi Zheng <zhengqi.arch@bytedance.com> |
Revert "mm: shrinkers: convert shrinker_rwsem to mutex" Patch series "revert shrinker_srcu related changes". This patch (of 7): This reverts commit cf2e309ebca7bb0916771839f9b580b06c778530. Kernel test robot reports -88.8% regression in stress-ng.ramfs.ops_per_sec test case [1], which is caused by commit f95bdb700bc6 ("mm: vmscan: make global slab shrink lockless"). The root cause is that SRCU has to be careful to not frequently check for SRCU read-side critical section exits. Therefore, even if no one is currently in the SRCU read-side critical section, synchronize_srcu() cannot return quickly. That's why unregister_shrinker() has become slower. After discussion, we will try to use the refcount+RCU method [2] proposed by Dave Chinner to continue to re-implement the lockless slab shrink. So revert the shrinker_mutex back to shrinker_rwsem first. [1]. https://lore.kernel.org/lkml/202305230837.db2c233f-yujie.liu@intel.com/ [2]. https://lore.kernel.org/lkml/ZIJhou1d55d4H1s0@dread.disaster.area/ Link: https://lkml.kernel.org/r/20230609081518.3039120-1-qi.zheng@linux.dev Link: https://lkml.kernel.org/r/20230609081518.3039120-2-qi.zheng@linux.dev Reported-by: kernel test robot <yujie.liu@intel.com> Closes: https://lore.kernel.org/oe-lkp/202305230837.db2c233f-yujie.liu@intel.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Kirill Tkhai <tkhai@ya.ru> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yujie Liu <yujie.liu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
cb65b282 |
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06-Jun-2023 |
Li Lingfeng <lilingfeng3@huawei.com> |
dm thin metadata: check fail_io before using data_sm Must check pmd->fail_io before using pmd->data_sm since pmd->data_sm may be destroyed by other processes. P1(kworker) P2(message) do_worker process_prepared process_prepared_discard_passdown_pt2 dm_pool_dec_data_range pool_message commit dm_pool_commit_metadata ↓ // commit failed metadata_operation_failed abort_transaction dm_pool_abort_metadata __open_or_format_metadata ↓ dm_sm_disk_open ↓ // open failed // pmd->data_sm is NULL dm_sm_dec_blocks ↓ // try to access pmd->data_sm --> UAF As shown above, if dm_pool_commit_metadata() and dm_pool_abort_metadata() fail in pool_message process, kworker may trigger UAF. Fixes: be500ed721a6 ("dm space maps: improve performance with inc/dec on ranges of blocks") Cc: stable@vger.kernel.org Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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cf2e309e |
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13-Mar-2023 |
Qi Zheng <zhengqi.arch@bytedance.com> |
mm: shrinkers: convert shrinker_rwsem to mutex Now there are no readers of shrinker_rwsem, so we can simply replace it with mutex lock. Link: https://lkml.kernel.org/r/20230313112819.38938-9-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Kirill Tkhai <tkhai@ya.ru> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Christian König <christian.koenig@amd.com> Cc: David Hildenbrand <david@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Sultan Alsawaf <sultan@kerneltoast.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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1c3fe2fa |
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07-Feb-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: avoid useless 'else' after 'break' or return' Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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1c131886 |
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06-Feb-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: prefer '"%s...", __func__' Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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2e84fecf |
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03-Feb-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: avoid split of quoted strings where possible Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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2d0f25cb |
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02-Feb-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: remove unnecessary braces from single statement blocks Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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0ef0b471 |
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01-Feb-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: add missing empty lines Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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a4a82ce3 |
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26-Jan-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: correct block comments format. Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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86a3238c |
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25-Jan-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: change "unsigned" to "unsigned int" Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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3bd94003 |
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25-Jan-2023 |
Heinz Mauelshagen <heinzm@redhat.com> |
dm: add missing SPDX-License-Indentifiers 'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has deprecated its use. Suggested-by: John Wiele <jwiele@redhat.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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7991dbff |
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08-Dec-2022 |
Zhihao Cheng <chengzhihao1@huawei.com> |
dm thin: Use last transaction's pmd->root when commit failed Recently we found a softlock up problem in dm thin pool btree lookup code due to corrupted metadata: Kernel panic - not syncing: softlockup: hung tasks CPU: 7 PID: 2669225 Comm: kworker/u16:3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: dm-thin do_worker [dm_thin_pool] Call Trace: <IRQ> dump_stack+0x9c/0xd3 panic+0x35d/0x6b9 watchdog_timer_fn.cold+0x16/0x25 __run_hrtimer+0xa2/0x2d0 </IRQ> RIP: 0010:__relink_lru+0x102/0x220 [dm_bufio] __bufio_new+0x11f/0x4f0 [dm_bufio] new_read+0xa3/0x1e0 [dm_bufio] dm_bm_read_lock+0x33/0xd0 [dm_persistent_data] ro_step+0x63/0x100 [dm_persistent_data] btree_lookup_raw.constprop.0+0x44/0x220 [dm_persistent_data] dm_btree_lookup+0x16f/0x210 [dm_persistent_data] dm_thin_find_block+0x12c/0x210 [dm_thin_pool] __process_bio_read_only+0xc5/0x400 [dm_thin_pool] process_thin_deferred_bios+0x1a4/0x4a0 [dm_thin_pool] process_one_work+0x3c5/0x730 Following process may generate a broken btree mixed with fresh and stale btree nodes, which could get dm thin trapped in an infinite loop while looking up data block: Transaction 1: pmd->root = A, A->B->C // One path in btree pmd->root = X, X->Y->Z // Copy-up Transaction 2: X,Z is updated on disk, Y write failed. // Commit failed, dm thin becomes read-only. process_bio_read_only dm_thin_find_block __find_block dm_btree_lookup(pmd->root) The pmd->root points to a broken btree, Y may contain stale node pointing to any block, for example X, which gets dm thin trapped into a dead loop while looking up Z. Fix this by setting pmd->root in __open_metadata(), so that dm thin will use the last transaction's pmd->root if commit failed. Fetch a reproducer in [Link]. Linke: https://bugzilla.kernel.org/show_bug.cgi?id=216790 Cc: stable@vger.kernel.org Fixes: 991d9fa02da0 ("dm: add thin provisioning target") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Acked-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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8111964f |
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30-Nov-2022 |
Zhihao Cheng <chengzhihao1@huawei.com> |
dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata Following concurrent processes: P1(drop cache) P2(kworker) drop_caches_sysctl_handler drop_slab shrink_slab down_read(&shrinker_rwsem) - LOCK A do_shrink_slab super_cache_scan prune_icache_sb dispose_list evict ext4_evict_inode ext4_clear_inode ext4_discard_preallocations ext4_mb_load_buddy_gfp ext4_mb_init_cache ext4_read_block_bitmap_nowait ext4_read_bh_nowait submit_bh dm_submit_bio do_worker process_deferred_bios commit metadata_operation_failed dm_pool_abort_metadata down_write(&pmd->root_lock) - LOCK B __destroy_persistent_data_objects dm_block_manager_destroy dm_bufio_client_destroy unregister_shrinker down_write(&shrinker_rwsem) thin_map | dm_thin_find_block ↓ down_read(&pmd->root_lock) --> ABBA deadlock , which triggers hung task: [ 76.974820] INFO: task kworker/u4:3:63 blocked for more than 15 seconds. [ 76.976019] Not tainted 6.1.0-rc4-00011-g8f17dd350364-dirty #910 [ 76.978521] task:kworker/u4:3 state:D stack:0 pid:63 ppid:2 [ 76.978534] Workqueue: dm-thin do_worker [ 76.978552] Call Trace: [ 76.978564] __schedule+0x6ba/0x10f0 [ 76.978582] schedule+0x9d/0x1e0 [ 76.978588] rwsem_down_write_slowpath+0x587/0xdf0 [ 76.978600] down_write+0xec/0x110 [ 76.978607] unregister_shrinker+0x2c/0xf0 [ 76.978616] dm_bufio_client_destroy+0x116/0x3d0 [ 76.978625] dm_block_manager_destroy+0x19/0x40 [ 76.978629] __destroy_persistent_data_objects+0x5e/0x70 [ 76.978636] dm_pool_abort_metadata+0x8e/0x100 [ 76.978643] metadata_operation_failed+0x86/0x110 [ 76.978649] commit+0x6a/0x230 [ 76.978655] do_worker+0xc6e/0xd90 [ 76.978702] process_one_work+0x269/0x630 [ 76.978714] worker_thread+0x266/0x630 [ 76.978730] kthread+0x151/0x1b0 [ 76.978772] INFO: task test.sh:2646 blocked for more than 15 seconds. [ 76.979756] Not tainted 6.1.0-rc4-00011-g8f17dd350364-dirty #910 [ 76.982111] task:test.sh state:D stack:0 pid:2646 ppid:2459 [ 76.982128] Call Trace: [ 76.982139] __schedule+0x6ba/0x10f0 [ 76.982155] schedule+0x9d/0x1e0 [ 76.982159] rwsem_down_read_slowpath+0x4f4/0x910 [ 76.982173] down_read+0x84/0x170 [ 76.982177] dm_thin_find_block+0x4c/0xd0 [ 76.982183] thin_map+0x201/0x3d0 [ 76.982188] __map_bio+0x5b/0x350 [ 76.982195] dm_submit_bio+0x2b6/0x930 [ 76.982202] __submit_bio+0x123/0x2d0 [ 76.982209] submit_bio_noacct_nocheck+0x101/0x3e0 [ 76.982222] submit_bio_noacct+0x389/0x770 [ 76.982227] submit_bio+0x50/0xc0 [ 76.982232] submit_bh_wbc+0x15e/0x230 [ 76.982238] submit_bh+0x14/0x20 [ 76.982241] ext4_read_bh_nowait+0xc5/0x130 [ 76.982247] ext4_read_block_bitmap_nowait+0x340/0xc60 [ 76.982254] ext4_mb_init_cache+0x1ce/0xdc0 [ 76.982259] ext4_mb_load_buddy_gfp+0x987/0xfa0 [ 76.982263] ext4_discard_preallocations+0x45d/0x830 [ 76.982274] ext4_clear_inode+0x48/0xf0 [ 76.982280] ext4_evict_inode+0xcf/0xc70 [ 76.982285] evict+0x119/0x2b0 [ 76.982290] dispose_list+0x43/0xa0 [ 76.982294] prune_icache_sb+0x64/0x90 [ 76.982298] super_cache_scan+0x155/0x210 [ 76.982303] do_shrink_slab+0x19e/0x4e0 [ 76.982310] shrink_slab+0x2bd/0x450 [ 76.982317] drop_slab+0xcc/0x1a0 [ 76.982323] drop_caches_sysctl_handler+0xb7/0xe0 [ 76.982327] proc_sys_call_handler+0x1bc/0x300 [ 76.982331] proc_sys_write+0x17/0x20 [ 76.982334] vfs_write+0x3d3/0x570 [ 76.982342] ksys_write+0x73/0x160 [ 76.982347] __x64_sys_write+0x1e/0x30 [ 76.982352] do_syscall_64+0x35/0x80 [ 76.982357] entry_SYSCALL_64_after_hwframe+0x63/0xcd Function metadata_operation_failed() is called when operations failed on dm pool metadata, dm pool will destroy and recreate metadata. So, shrinker will be unregistered and registered, which could down write shrinker_rwsem under pmd_write_lock. Fix it by allocating dm_block_manager before locking pmd->root_lock and destroying old dm_block_manager after unlocking pmd->root_lock, then old dm_block_manager is replaced with new dm_block_manager under pmd->root_lock. So, shrinker register/unregister could be done without holding pmd->root_lock. Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216676 Cc: stable@vger.kernel.org #v5.2+ Fixes: e49e582965b3 ("dm thin: add read only and fail io modes") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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3534e5a5 |
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14-Jul-2022 |
Luo Meng <luomeng12@huawei.com> |
dm thin: fix use-after-free crash in dm_sm_register_threshold_callback Fault inject on pool metadata device reports: BUG: KASAN: use-after-free in dm_pool_register_metadata_threshold+0x40/0x80 Read of size 8 at addr ffff8881b9d50068 by task dmsetup/950 CPU: 7 PID: 950 Comm: dmsetup Tainted: G W 5.19.0-rc6 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x34/0x44 print_address_description.constprop.0.cold+0xeb/0x3f4 kasan_report.cold+0xe6/0x147 dm_pool_register_metadata_threshold+0x40/0x80 pool_ctr+0xa0a/0x1150 dm_table_add_target+0x2c8/0x640 table_load+0x1fd/0x430 ctl_ioctl+0x2c4/0x5a0 dm_ctl_ioctl+0xa/0x10 __x64_sys_ioctl+0xb3/0xd0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This can be easily reproduced using: echo offline > /sys/block/sda/device/state dd if=/dev/zero of=/dev/mapper/thin bs=4k count=10 dmsetup load pool --table "0 20971520 thin-pool /dev/sda /dev/sdb 128 0 0" If a metadata commit fails, the transaction will be aborted and the metadata space maps will be destroyed. If a DM table reload then happens for this failed thin-pool, a use-after-free will occur in dm_sm_register_threshold_callback (called from dm_pool_register_metadata_threshold). Fix this by in dm_pool_register_metadata_threshold() by returning the -EINVAL error if the thin-pool is in fail mode. Also fail pool_ctr() with a new error message: "Error registering metadata threshold". Fixes: ac8c3f3df65e4 ("dm thin: generate event when metadata threshold passed") Cc: stable@vger.kernel.org Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Luo Meng <luomeng12@huawei.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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75274a4b |
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15-Feb-2022 |
Zhiqiang Liu <liuzhiqiang26@huawei.com> |
dm thin metadata: remove unused dm_thin_remove_block and __remove Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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6dcbb52c |
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17-Oct-2021 |
Christoph Hellwig <hch@lst.de> |
dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them Use the proper helpers to read the block device size. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20211018101130.1838532-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
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be500ed7 |
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13-Apr-2021 |
Joe Thornber <ejt@redhat.com> |
dm space maps: improve performance with inc/dec on ranges of blocks When we break sharing on btree nodes we typically need to increment the reference counts to every value held in the node. This can cause a lot of repeated calls to the space maps. Fix this by changing the interface to the space map inc/dec methods to take ranges of adjacent blocks to be operated on. For installations that are using a lot of snapshots this will reduce cpu overhead of fundamental operations such as provisioning a new block, or deleting a snapshot, by as much as 10 times. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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1e0dcca9 |
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09-Jan-2021 |
Christoph Hellwig <hch@lst.de> |
dm: use bdev_read_only to check if a device is read-only dm-thin and dm-cache also work on partitions, so use the proper interface to check if the device is read-only. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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399c9bdb |
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15-Sep-2020 |
Huaisheng Ye <yehs1@lenovo.com> |
dm thin metadata: Remove unused local variable when create thin and snap The local variable disk details is not used during the creating of thin & snap devices. Remove them from dm-thin-metadata, and add pointer validity check for pointer value in btree_lookup_raw. Skip memory copy when the caller doesn't need the value. Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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3a653b20 |
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01-Sep-2020 |
Ye Bin <yebin10@huawei.com> |
dm thin metadata: Fix use-after-free in dm_bm_set_read_only The following error ocurred when testing disk online/offline: [ 301.798344] device-mapper: thin: 253:5: aborting current metadata transaction [ 301.848441] device-mapper: thin: 253:5: failed to abort metadata transaction [ 301.849206] Aborting journal on device dm-26-8. [ 301.850489] EXT4-fs error (device dm-26) in __ext4_new_inode:943: Journal has aborted [ 301.851095] EXT4-fs (dm-26): Delayed block allocation failed for inode 398742 at logical offset 181 with max blocks 19 with error 30 [ 301.854476] BUG: KASAN: use-after-free in dm_bm_set_read_only+0x3a/0x40 [dm_persistent_data] Reason is: metadata_operation_failed abort_transaction dm_pool_abort_metadata __create_persistent_data_objects r = __open_or_format_metadata if (r) --> If failed will free pmd->bm but pmd->bm not set NULL dm_block_manager_destroy(pmd->bm); set_pool_mode dm_pool_metadata_read_only(pool->pmd); dm_bm_set_read_only(pmd->bm); --> use-after-free Add checks to see if pmd->bm is NULL in dm_bm_set_read_only and dm_bm_set_read_write functions. If bm is NULL it means creating the bm failed and so dm_bm_is_read_only must return true. Signed-off-by: Ye Bin <yebin10@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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219403d7 |
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01-Sep-2020 |
Ye Bin <yebin10@huawei.com> |
dm thin metadata: Avoid returning cmd->bm wild pointer on error Maybe __create_persistent_data_objects() caller will use PTR_ERR as a pointer, it will lead to some strange things. Signed-off-by: Ye Bin <yebin10@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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3918e066 |
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23-Feb-2020 |
Theodore Ts'o <tytso@mit.edu> |
dm thin metadata: fix lockdep complaint [ 3934.173244] ====================================================== [ 3934.179572] WARNING: possible circular locking dependency detected [ 3934.185884] 5.4.21-xfstests #1 Not tainted [ 3934.190151] ------------------------------------------------------ [ 3934.196673] dmsetup/8897 is trying to acquire lock: [ 3934.201688] ffffffffbce82b18 (shrinker_rwsem){++++}, at: unregister_shrinker+0x22/0x80 [ 3934.210268] but task is already holding lock: [ 3934.216489] ffff92a10cc5e1d0 (&pmd->root_lock){++++}, at: dm_pool_metadata_close+0xba/0x120 [ 3934.225083] which lock already depends on the new lock. [ 3934.564165] Chain exists of: shrinker_rwsem --> &journal->j_checkpoint_mutex --> &pmd->root_lock For a more detailed lockdep report, please see: https://lore.kernel.org/r/20200220234519.GA620489@mit.edu We shouldn't need to hold the lock while are just tearing down and freeing the whole metadata pool structure. Fixes: 44d8ebf436399a4 ("dm thin metadata: use pool locking at end of dm_pool_metadata_close") Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
44d8ebf4 |
|
13-Jan-2020 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: use pool locking at end of dm_pool_metadata_close Ensure that the pool is locked during calls to __commit_transaction and __destroy_persistent_data_objects. Just being consistent with locking, but reality is dm_pool_metadata_close is called once pool is being destroyed so access to pool shouldn't be contended. Also, use pmd_write_lock_in_core rather than __pmd_write_lock in dm_pool_commit_metadata and rename __pmd_write_lock to pmd_write_lock_in_core -- there was no need for the alias. In addition, verify that the pool is locked in __commit_transaction(). Fixes: 873f258becca ("dm thin metadata: do not write metadata if no changes occurred") Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
43069040 |
|
29-Dec-2019 |
Jeffle Xu <jefflexu@linux.alibaba.com> |
dm thin metadata: Fix trivial math error in on-disk format documentation Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
63ee92d1 |
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23-Dec-2019 |
zhengbin <zhengbin13@huawei.com> |
dm thin metadata: use true/false for bool variable Fixes coccicheck warning: drivers/md/dm-thin-metadata.c:814:3-14: WARNING: Assignment of 0/1 to bool variable drivers/md/dm-thin-metadata.c:1109:1-12: WARNING: Assignment of 0/1 to bool variable drivers/md/dm-thin-metadata.c:1621:1-12: WARNING: Assignment of 0/1 to bool variable drivers/md/dm-thin-metadata.c:1652:1-12: WARNING: Assignment of 0/1 to bool variable drivers/md/dm-thin-metadata.c:1706:1-12: WARNING: Assignment of 0/1 to bool variable Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
ecda7c02 |
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04-Dec-2019 |
Nikos Tsironis <ntsironis@arrikto.com> |
dm thin metadata: Add support for a pre-commit callback Add support for one pre-commit callback which is run right before the metadata are committed. This allows the thin provisioning target to run a callback before the metadata are committed and is required by the next commit. Cc: stable@vger.kernel.org Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com> Acked-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
54fa16ee |
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02-Jul-2019 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: check if in fail_io mode when setting needs_check Check if in fail_io mode at start of dm_pool_metadata_set_needs_check(). Otherwise dm_pool_metadata_set_needs_check()'s superblock_lock() can crash in dm_bm_write_lock() while accessing the block manager object that was previously destroyed as part of a failed dm_pool_abort_metadata() that ultimately set fail_io to begin with. Also, update DMERR() message to more accurately describe superblock_lock() failure. Cc: stable@vger.kernel.org Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
873f258b |
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18-Apr-2019 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: do not write metadata if no changes occurred Otherwise, just activating a thin-pool and thin device and then deactivating them will cause the thin-pool metadata to be changed (e.g. superblock written) -- even without any metadata being changed. Add 'in_service' flag to struct dm_pool_metadata and set it in pmd_write_lock() because all on-disk metadata changes must take a write lock of pmd->root_lock. Once 'in_service' is set it is never cleared. __commit_transaction() will return 0 if 'in_service' is not set. dm_pool_commit_metadata() is updated to use __pmd_write_lock() so that it isn't the sole reason for putting a thin-pool in service. Also fix dm_pool_commit_metadata() to open the next transaction if the return from __commit_transaction() is 0. Not seeing why the early return ever made since for a return of 0 given that dm-io's async_io(), as used by bufio, always returns 0. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
6a1b1ddc |
|
15-Apr-2019 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: add wrappers for managing write locking of metadata No functional change, but this prepares to hook off of pmd_write_lock() with additional functionality (as provided in next commit). Suggested-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
a1ed4d9e |
|
15-Apr-2019 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: check __commit_transaction()'s return Fix __reserve_metadata_snap() to return early if __commit_transaction() fails. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
d445bd9c |
|
15-Jan-2019 |
Joe Thornber <ejt@redhat.com> |
dm thin: fix passdown_double_checking_shared_status() Commit 00a0ea33b495 ("dm thin: do not queue freed thin mapping for next stage processing") changed process_prepared_discard_passdown_pt1() to increment all the blocks being discarded until after the passdown had completed to avoid them being prematurely reused. IO issued to a thin device that breaks sharing with a snapshot, followed by a discard issued to snapshot(s) that previously shared the block(s), results in passdown_double_checking_shared_status() being called to iterate through the blocks double checking their reference count is zero and issuing the passdown if so. So a side effect of commit 00a0ea33b495 is passdown_double_checking_shared_status() was broken. Fix this by checking if the block reference count is greater than 1. Also, rename dm_pool_block_is_used() to dm_pool_block_is_shared(). Fixes: 00a0ea33b495 ("dm thin: do not queue freed thin mapping for next stage processing") Cc: stable@vger.kernel.org # 4.9+ Reported-by: ryan.p.norwood@gmail.com Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
013ad043 |
|
13-Sep-2018 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: fix __udivdi3 undefined on 32-bit sector_div() is only viable for use with sector_t. dm_block_t is typedef'd to uint64_t -- so use div_u64() instead. Fixes: 3ab918281 ("dm thin metadata: try to avoid ever aborting transactions") Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
3ab91828 |
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10-Sep-2018 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: try to avoid ever aborting transactions Committing a transaction can consume some metadata of it's own, we now reserve a small amount of metadata to cover this. Free metadata reported by the kernel will not include this reserve. If any of the reserve has been used after a commit we enter a new internal state PM_OUT_OF_METADATA_SPACE. This is reported as PM_READ_ONLY, so no userland changes are needed. If the metadata device is resized the pool will move back to PM_WRITE. These changes mean we never need to abort and rollback a transaction due to running out of metadata space. This is particularly important because there have been a handful of reports of data corruption against DM thin-provisioning that can all be attributed to the thin-pool having ran out of metadata space. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
7ccdbf85 |
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18-Jun-2018 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: remove needless work from __commit_transaction Commit 5a32083d03fb5 ("dm: take care to copy the space map roots before locking the superblock") properly removed the calls to dm_sm_root_size() from __write_initial_superblock(). But the dm_sm_root_size() calls were left dangling in __commit_transaction(). Fixes: 5a32083d03fb5 ("dm: take care to copy the space map roots before locking the superblock") Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
490ae017 |
|
12-Dec-2017 |
Dennis Yang <dennisyang@qnap.com> |
dm thin metadata: THIN_MAX_CONCURRENT_LOCKS should be 6 For btree removal, there is a corner case that a single thread could takes 6 locks which is more than THIN_MAX_CONCURRENT_LOCKS(5) and leads to deadlock. A btree removal might eventually call rebalance_children()->rebalance3() to rebalance entries of three neighbor child nodes when shadow_spine has already acquired two write locks. In rebalance3(), it tries to shadow and acquire the write locks of all three child nodes. However, shadowing a child node requires acquiring a read lock of the original child node and a write lock of the new block. Although the read lock will be released after block shadowing, shadowing the third child node in rebalance3() could still take the sixth lock. (2 write locks for shadow_spine + 2 write locks for the first two child nodes's shadow + 1 write lock for the last child node's shadow + 1 read lock for the last child node) Cc: stable@vger.kernel.org Signed-off-by: Dennis Yang <dennisyang@qnap.com> Acked-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
91bcdb92 |
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15-May-2017 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: call precommit before saving the roots These calls were the wrong way round in __write_initial_superblock. Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
73cbca6a |
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27-Apr-2017 |
Bart Van Assche <bvanassche@acm.org> |
dm block manager: remove an unused argument from dm_block_manager_create() The 'cache_size' argument of dm_block_manager_create() has never been used. Remove it along with the definitions of the constants passed as the 'cache_size' argument. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
2a0fbffb |
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01-Jul-2016 |
Joe Thornber <ejt@redhat.com> |
dm thin: fix a race condition between discarding and provisioning a block The discard passdown was being issued after the block was unmapped, which meant the block could be reprovisioned whilst the passdown discard was still in flight. We can only identify unshared blocks (safe to do a passdown a discard to) once they're unmapped and their ref count hits zero. Block ref counts are now used to guard against concurrent allocation of these blocks that are being discarded. So now we unmap the block, issue passdown discards, and the immediately increment ref counts for regions that have been discarded via passed down (this is safe because allocation occurs within the same thread). We then decrement ref counts once the passdown discard IO is complete -- signaling these blocks may now be allocated. This fixes the potential for corruption that was reported here: https://www.redhat.com/archives/dm-devel/2016-June/msg00311.html Reported-by: Dennis Yang <dennisyang@qnap.com> Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
2eae9e44 |
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01-Mar-2016 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: don't issue prefetches if a transaction abort has failed If a transaction abort has failed then we can no longer use the metadata device. Typically this happens if the superblock is unreadable. This fix addresses a crash seen during metadata device failure testing. Fixes: 8a01a6af75 ("dm thin: prefetch missing metadata pages") Cc: stable@vger.kernel.org # 3.19+ Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
29f929b5 |
|
21-Jan-2016 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: remove needless newline from subtree_dec() DMERR message Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
086fbbbd |
|
07-Dec-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: make dm_thin_find_mapped_range() atomic Refactor dm_thin_find_mapped_range() so that it takes the read lock on the metadata's lock; rather than relying on finer grained locking that is pushed down inside dm_thin_find_next_mapped_block() and dm_thin_find_block(). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
3d5f6733 |
|
05-Nov-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: speed up discard of partially mapped volumes Use dm_btree_lookup_next() to more quickly discard partially mapped volumes. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
49e99fc7 |
|
09-Dec-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: fix bug when taking a metadata snapshot When you take a metadata snapshot the btree roots for the mapping and details tree need to have their reference counts incremented so they persist for the lifetime of the metadata snap. The roots being incremented were those currently written in the superblock, which could possibly be out of date if concurrent IO is triggering new mappings, breaking of sharing, etc. Fix this by performing a commit with the metadata lock held while taking a metadata snapshot. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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#
993ceab9 |
|
01-Dec-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: fix bug in dm_thin_remove_range() dm_btree_remove_leaves() only unmaps a contiguous region so we need a loop, in __remove_range(), to handle ranges that contain multiple regions. A new btree function, dm_btree_lookup_next(), is introduced which is more efficiently able to skip over regions of the thin device which aren't mapped. __remove_range() uses dm_btree_lookup_next() for each iteration of __remove_range()'s loop. Also, improve description of dm_btree_remove_leaves(). Fixes: 6550f075 ("dm thin metadata: add dm_thin_remove_range()") Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.1+
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#
4c7da06f |
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22-Oct-2015 |
Mikulas Patocka <mpatocka@redhat.com> |
dm persistent data: eliminate unnecessary return values dm_bm_unlock and dm_tm_unlock return an integer value but the returned value is always 0. The calling code sometimes checks the return value and sometimes doesn't. Eliminate these unnecessary return values and also the checks for them. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
7f518ad0 |
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12-Aug-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: delete btrees when releasing metadata snapshot The device details and mapping trees were just being decremented before. Now btree_del() is called to do a deep delete. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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#
b1f11aff |
|
11-Jun-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: fix a race when entering fail mode In dm_thin_find_block() the ->fail_io flag was checked outside the metadata device's root_lock, causing dm_thin_find_block() to race with the setting of this flag. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
6550f075 |
|
13-Apr-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: add dm_thin_remove_range() Removes a range of blocks from the btree. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
a5d895a9 |
|
15-Apr-2015 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: add dm_thin_find_mapped_range() Retrieve the next run of contiguously mapped blocks. Useful for working out where to break up IO. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
49f154c7 |
|
23-Apr-2015 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: remove in-core 'read_only' flag Leverage the block manager's read_only flag instead of duplicating it; access with new dm_bm_is_read_only() method. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
9cb1397d |
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01-Jan-2015 |
Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> |
dm thin metadata: remove unused dm_pool_get_data_block_size() The thin-pool target doesn't display the data block size as part of its table status, unlike the dm-cache target, so there is no need for dm_pool_get_data_block_size(). This was found using cppcheck. Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
8a01a6af |
|
06-Oct-2014 |
Joe Thornber <ejt@redhat.com> |
dm thin: prefetch missing metadata pages Prefetch metadata at the start of the worker thread and then again every 128th bio processed from the deferred list. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
e5cfc69a |
|
06-Oct-2014 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: change dm_thin_find_block to allow blocking, but not issuing, IO This change is a prerequisite for allowing metadata to be prefetched. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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#
9aec8629 |
|
14-Jul-2014 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: do not allow the data block size to change The block size for the thin-pool's data device must remained fixed for the life of the thin-pool. Disallow any attempt to change the thin-pool's data block size. It should be noted that attempting to change the data block size via thin-pool table reload will be ignored as a side-effect of the thin-pool handover that the thin-pool target does during thin-pool table reload. Here is an example outcome of attempting to load a thin-pool table that reduced the thin-pool's data block size from 1024K to 512K. Before: kernel: device-mapper: thin: 253:4: growing the data device from 204800 to 409600 blocks After: kernel: device-mapper: thin metadata: changing the data block size (from 2048 to 1024) is not supported kernel: device-mapper: table: 253:4: thin-pool: Error creating metadata object kernel: device-mapper: ioctl: error adding target to table Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com> Cc: stable@vger.kernel.org
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#
5a32083d |
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27-Mar-2014 |
Joe Thornber <ejt@redhat.com> |
dm: take care to copy the space map roots before locking the superblock In theory copying the space map root can fail, but in practice it never does because we're careful to check what size buffer is needed. But make certain we're able to copy the space map roots before locking the superblock. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # drop dm-era and dm-cache changes as needed
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#
07f2b6e0 |
|
14-Feb-2014 |
Mike Snitzer <snitzer@redhat.com> |
dm thin: ensure user takes action to validate data and metadata consistency If a thin metadata operation fails the current transaction will abort, whereby causing potential for IO layers up the stack (e.g. filesystems) to have data loss. As such, set THIN_METADATA_NEEDS_CHECK_FLAG in the thin metadata's superblock which: 1) requires the user verify the thin metadata is consistent (e.g. use thin_check, etc) 2) suggests the user verify the thin data is consistent (e.g. use fsck) The only way to clear the superblock's THIN_METADATA_NEEDS_CHECK_FLAG is to run thin_repair. On metadata operation failure: abort current metadata transaction, set pool in read-only mode, and now set the needs_check flag. As part of this change, constraints are introduced or relaxed: * don't allow a pool to transition to write mode if needs_check is set * don't allow data or metadata space to be resized if needs_check is set * if a thin pool's metadata space is exhausted: the kernel will now force the user to take the pool offline for repair before the kernel will allow the metadata space to be extended. Also, update Documentation to include information about when the thin provisioning target commits metadata, how it handles metadata failures and running out of space. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Joe Thornber <ejt@redhat.com>
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#
7d48935e |
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12-Feb-2014 |
Mike Snitzer <snitzer@redhat.com> |
dm thin: allow metadata space larger than supported to go unused It was always intended that a user could provide a thin metadata device that is larger than the max supported by the on-disk format. The extra space would just go unused. Unfortunately that never worked. If the user attempted to use a larger metadata device on creation they would get an error like the following: device-mapper: space map common: space map too large device-mapper: transaction manager: couldn't create metadata space map device-mapper: thin metadata: tm_create_with_sm failed device-mapper: table: 252:17: thin-pool: Error creating metadata object device-mapper: ioctl: error adding target to table Fix this by allowing the initial metadata space map creation to cap its size at the max number of blocks supported (DM_SM_METADATA_MAX_BLOCKS). get_metadata_dev_size() must also impose DM_SM_METADATA_MAX_BLOCKS (via THIN_METADATA_MAX_SECTORS), otherwise extending metadata would cap at THIN_METADATA_MAX_SECTORS_WARNING (which is larger than supported). Also, the calculation for THIN_METADATA_MAX_SECTORS didn't account for the sizeof the disk_bitmap_header. So the supported maximum metadata size is a bit smaller (reduced from 33423360 to 33292800 sectors). Lastly, remove the "excess space will not be used" warning message from get_metadata_dev_size(); it resulted in printing the warning multiple times. Factor out warn_if_metadata_device_too_big(), call it from pool_ctr() and maybe_resize_metadata_dev(). Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
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#
4d1662a3 |
|
06-Feb-2014 |
Mike Snitzer <snitzer@redhat.com> |
dm thin: avoid metadata commit if a pool's thin devices haven't changed Commit 905e51b ("dm thin: commit outstanding data every second") introduced a periodic commit. This commit occurs regardless of whether any thin devices have made changes. Fix the periodic commit to check if any of a pool's thin devices have changed using dm_pool_changed_this_transaction(). Reported-by: Alexander Larsson <alexl@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com> Cc: stable@vger.kernel.org
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#
19fa1a67 |
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16-Dec-2013 |
Joe Thornber <ejt@redhat.com> |
dm thin: fix discard support to a previously shared block If a snapshot is created and later deleted the origin dm_thin_device's snapshotted_time will have been updated to reflect the snapshot's creation time. The 'shared' flag in the dm_thin_lookup_result struct returned from dm_thin_find_block() is an approximation based on snapshotted_time -- this is done to avoid 0(n), or worse, time complexity. In this case, the shared flag would be true. But because the 'shared' flag reflects an approximation a block can be incorrectly assumed to be shared (e.g. false positive for 'shared' because the snapshot no longer exists). This could result in discards issued to a thin device not being passed down to the pool's underlying data device. To fix this we double check that a thin block is really still in-use after a mapping is removed using dm_pool_block_is_used(). If the reference count for a block is now zero the discard is allowed to be passed down. Also add a 'definitely_not_shared' member to the dm_thin_new_mapping structure -- reflects that the 'shared' flag in the response from dm_thin_find_block() can only be held as definitive if false is returned. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1043527 Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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#
9b7aaa64 |
|
04-Dec-2013 |
Joe Thornber <ejt@redhat.com> |
dm thin: allow pool in read-only mode to transition to read-write mode A thin-pool may be in read-only mode because the pool's data or metadata space was exhausted. To allow for recovery, by adding more space to the pool, we must allow a pool to transition from PM_READ_ONLY to PM_WRITE mode. Otherwise, running out of space will render the pool permanently read-only. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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#
ac8c3f3d |
|
10-May-2013 |
Joe Thornber <ejt@redhat.com> |
dm thin: generate event when metadata threshold passed Generate a dm event when the amount of remaining thin pool metadata space falls below a certain level. The threshold is taken to be a quarter of the size of the metadata device with a minimum threshold of 4MB. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
24347e95 |
|
10-May-2013 |
Joe Thornber <ejt@redhat.com> |
dm thin: detect metadata device resizing Allow the dm thin pool metadata device to be extended. Whenever a pool is resumed, detect whether the size of the metadata device has increased, and if so, extend the metadata to use the new space. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
|
#
b17446df |
|
10-May-2013 |
Joe Thornber <ejt@redhat.com> |
dm thin: refactor data dev resize Refactor device size functions in preparation for similar metadata device resizing functions. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
|
#
018cede9 |
|
01-Mar-2013 |
Mike Snitzer <snitzer@redhat.com> |
dm persistent data: set some btree fn parms const Mark some constant parameters constant in some dm-btree functions. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
e3cbf945 |
|
21-Dec-2012 |
Joe Thornber <ejt@redhat.com> |
dm persistent data: fix nested btree deletion When deleting nested btrees, the code forgets to delete the innermost btree. The thin-metadata code serendipitously compensates for this by claiming there is one extra layer in the tree. This patch corrects both problems. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
da105ed5 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: introduce dm_pool_abort_metadata Introduce dm_pool_abort_metadata to abort the current metadata transaction. Generally this will only be called when bad things are happening and dm-thin is trying to roll back to a good state for read-only mode. It's complicated by the fact that the metadata device may have failed completely causing the abort to be unable to read the old transaction. In this case the metadata object is placed in a 'fail' mode and everything fails apart from destroying it. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
12ba58af |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: introduce dm_pool_metadata_set_read_only Introduce dm_pool_metadata_set_read_only to put the underlying block manager into read-only mode. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
40db5a53 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: add dm_thin_changed_this_transaction Introduce dm_thin_changed_this_transaction to dm-thin-metadata to publish a useful bit of information we're already tracking. This will help dm thin decide when to commit. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
66b1edc0 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: add format option to dm_pool_metadata_open Add a parameter to dm_pool_metadata_open to indicate whether or not an unformatted metadata area should be formatted. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
0fa5b17b |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: tidy up open and format error paths Tidy up error path in __open_metadata and __format_metadata in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
d73ec525 |
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27-Jul-2012 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: only check incompat features on open Factor out __check_incompat_features and only call it once when we open the metadata device rather than at the beginning of every transaction. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
b7939951 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: remove duplicate pmd initialisation Remove some duplicate initialisation of struct dm_pool_metadata. These pmd fields are initialised by both: __format_metadata's calls to dm_btree_empty __write_initial_superblock + __begin_transaction Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
8801e069 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: remove create parameter from __create_persistent_data_objects Remove 'create' parameter from __create_persistent_data_objects() in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
237074c0 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: move __superblock_all_zeroes to __open_or_format_metadata Move the check for __superblock_all_zeroes from __create_persistent_data_objects() down to __open_or_format_metadata in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
a97e5e6f |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: remove nr_blocks arg from __create_persistent_data_objects Remove nr_blocks arg from __create_persistent_data_objects in dm-thin-metadata. It was always passed as zero. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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e4d2205c |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: split __open or format metadata Split __open_or_format_metadata into __format_metadata and __open_metadata in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
d6332814 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: use struct dm_pool_metadata members in __open_or_format_metadata Clean up __open_or_format_metadata in dm-thin-metadata by using struct dm_pool_metadata members to replace local variables. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
583ceee2 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: zero unused superblock uuid Zero the unused uuid when initialising the metadata superblock. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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270938ba |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: lift __begin_transaction out of __write_initial_superblock Lift the call to __begin_transaction out of __write_initial_superblock in dm-thin-metadata. Called higher up the call chain now. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
10d2a9ff |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: move dm_commit_pool_metadata into __write_initial_superblock Move dm_commit_pool_metadata inline into __write_initial_superblock in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
9cb6653f |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: factor out __write_initial_superblock Factor out __write_initial_superblock and also pull some other initial creation code out of dm_pool_metadata_open. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
6a0ebd31 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: lift some initialisation out of __open_or_format_metadata Lift some initialisation out of __open_or_format_metadata in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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f9dd9352 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: factor __destroy_persistent_data out of dm_pool_metadata_close Factor __destroy_persistent_data_objects out of dm_pool_metadata_close. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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332627db |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: move bm creation code into create_persistent_data_objects Move block manager creation and the check for unformatted metadata into __create_persistent_data_objects(). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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77f49a40 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: rename init_pmd to __create_persistent_data_objects Rename init_pmd to __create_persistent_data_objects in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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#
25971192 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: wrap superblock locking Introduce wrappers to handle write locking the superblock appropriately. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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384ef0e6 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm persistent data: tidy transaction manager creation fns Tidy the transaction manager creation functions. They no longer lock the superblock. Superblock locking is pulled out to the caller. Also export dm_bm_write_lock_zero. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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eb04cf63 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: stop tracking need for commit Remove an optimisation that tracks whether or not a thin metadata commit is needed. If dm_pool_commit_metadata() is called and no changes have been made to the metadata then this optimisation avoided writing to disk. Removing because we're going to do something better later. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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51a0f659 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm persistent data: create new dm_block_manager struct This patch introduces a separate struct for the block_manager. It also uses IS_ERR to check the return value of dm_bufio_client_create instead of testing incorrectly for NULL. Prior to this patch a struct dm_block_manager was really an alias for a struct dm_bufio_client. We want to add some functionality to the block manager that will require extra fields, so this one to one mapping is no longer valid. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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41675aea |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: factor __setup_btree_details out of init_pmd Factor __setup_btree_details out of init_pmd in dm-thin-metadata. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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8c971178 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: introduce THIN_MAX_CONCURRENT_LOCKS Introduce THIN_MAX_CONCURRENT_LOCKS into dm-thin-metadata to give a name to an otherwise "magic" number. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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d973ac19 |
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27-Jul-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: remove pointless label from __commit_transaction Remove the pointless label 'out' from __commit_transaction in dm-thin-metadata.c Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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17b7d63f |
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27-Jul-2012 |
Mike Snitzer <snitzer@redhat.com> |
dm thin: clean up compiler warning Clean up "warning: dubious: !x & y". Also make it clear that __snapshotted_since() returns a bool and that dm_thin_lookup_result's 'shared' member is a flag. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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cc8394d8 |
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02-Jun-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin: provide userspace access to pool metadata This patch implements two new messages that can be sent to the thin pool target allowing it to take a snapshot of the _metadata_. This, read-only snapshot can be accessed by userland, concurrently with the live target. Only one metadata snapshot can be held at a time. The pool's status line will give the block location for the current msnap. Since version 0.1.5 of the userland thin provisioning tools, the thin_dump program displays the msnap as follows: thin_dump -m <msnap root> <metadata dev> Available here: https://github.com/jthornber/thin-provisioning-tools Now that userland can access the metadata we can do various things that have traditionally been kernel side tasks: i) Incremental backups. By using metadata snapshots we can work out what blocks have changed over time. Combined with data snapshots we can ensure the data doesn't change while we back it up. A short proof of concept script can be found here: https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb ii) Migration of thin devices from one pool to another. iii) Merging snapshots back into an external origin. iv) Asyncronous replication. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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c4a69ecd |
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28-Mar-2012 |
Mike Snitzer <snitzer@redhat.com> |
dm thin: relax hard limit on the maximum size of a metadata device The thin metadata format can only make use of a device that is <= THIN_METADATA_MAX_SECTORS (currently 15.9375 GB). Therefore, there is no practical benefit to using a larger device. However, it may be that other factors impose a certain granularity for the space that is allocated to a device (E.g. lvm2 can impose a coarse granularity through the use of large, >= 1 GB, physical extents). Rather than reject a larger metadata device, during thin-pool device construction, switch to allowing it but issue a warning if a device larger than THIN_METADATA_MAX_SECTORS_WARNING (16 GB) is provided. Any space over 15.9375 GB will not be used. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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fef838cc |
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28-Mar-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: pass correct space map to dm_sm_root_size Fix a harmless typo. The root is a chunk of data that gets written to the superblock. This data is used to recreate the space map when opening a metadata area. We have two space maps; one tracking space on the metadata device and one of the data device. Both of these use the same format for their root, so this typo was harmless. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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af63bcb8 |
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07-Mar-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: decrement counter after removing mapped block Correct the number of mapped sectors shown on a thin device's status line by decrementing td->mapped_blocks in __remove() each time a block is removed. Signed-off-by: Joe Thornber <ejt@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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4469a5f3 |
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07-Mar-2012 |
Joe Thornber <ejt@redhat.com> |
dm thin metadata: unlock superblock in init_pmd error path If dm_sm_disk_create() fails the superblock must be unlocked. Signed-off-by: Joe Thornber <ejt@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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1f3db25d |
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07-Mar-2012 |
Mike Snitzer <snitzer@redhat.com> |
dm thin metadata: remove incorrect close_device on creation error paths The __open_device() error paths in __create_thin() and __create_snap() incorrectly call __close_device() even if td was not initialized by __open_device(). Remove this. Also document __open_device() return values, remove a redundant td->changed = 1 in __create_thin(), and insert an additional safeguard against creating an already-existing device. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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991d9fa0 |
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31-Oct-2011 |
Joe Thornber <thornber@redhat.com> |
dm: add thin provisioning target Initial EXPERIMENTAL implementation of device-mapper thin provisioning with snapshot support. The 'thin' target is used to create instances of the virtual devices that are hosted in the 'thin-pool' target. The thin-pool target provides data sharing among devices. This sharing is made possible using the persistent-data library in the previous patch. The main highlight of this implementation, compared to the previous implementation of snapshots, is that it allows many virtual devices to be stored on the same data volume, simplifying administration and allowing sharing of data between volumes (thus reducing disk usage). Another big feature is support for arbitrary depth of recursive snapshots (snapshots of snapshots of snapshots ...). The previous implementation of snapshots did this by chaining together lookup tables, and so performance was O(depth). This new implementation uses a single data structure so we don't get this degradation with depth. For further information and examples of how to use this, please read Documentation/device-mapper/thin-provisioning.txt Signed-off-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
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