f2fs: unify the error handling of f2fs_is_valid_blkaddr

There are some cases of f2fs_is_valid_blkaddr not handled as
ERROR_INVALID_BLKADDR,so unify the error handling about all of
f2fs_is_valid_blkaddr.
Do f2fs_handle_error in __f2fs_is_valid_blkaddr for cleanup.

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: relocate f2fs_precache_extents() in f2fs_swap_activate()

This patch exchangs position of f2fs_precache_extents() and
filemap_fdatawrite(), so that f2fs_precache_extents() can load
extent info after physical addresses of all data are fixed.

Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix blkofs_end correctly in f2fs_migrate_blocks()

In f2fs_migrate_blocks(), when traversing blocks in last section,
blkofs_end should be (start_blk + blkcnt - 1) % blk_per_sec, fix it.

Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to handle segment allocation failure correctly

If CONFIG_F2FS_CHECK_FS is off, and for very rare corner case that
we run out of free segment, we should not panic kernel, instead,
let's handle such error correctly in its caller.

Signed-off-by: Chao Yu <chao@kernel.org>
Tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support file pinning for zoned devices

Support file pinning with conventional storage area for zoned devices

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: deprecate io_bits

Let's deprecate an unused io_bits feature to save CPU cycles and memory.

Reviewed-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix NULL pointer dereference in f2fs_submit_page_write()

BUG: kernel NULL pointer dereference, address: 0000000000000014
RIP: 0010:f2fs_submit_page_write+0x6cf/0x780 [f2fs]
Call Trace:
<TASK>
? show_regs+0x6e/0x80
? __die+0x29/0x70
? page_fault_oops+0x154/0x4a0
? prb_read_valid+0x20/0x30
? __irq_work_queue_local+0x39/0xd0
? irq_work_queue+0x36/0x70
? do_user_addr_fault+0x314/0x6c0
? exc_page_fault+0x7d/0x190
? asm_exc_page_fault+0x2b/0x30
? f2fs_submit_page_write+0x6cf/0x780 [f2fs]
? f2fs_submit_page_write+0x736/0x780 [f2fs]
do_write_page+0x50/0x170 [f2fs]
f2fs_outplace_write_data+0x61/0xb0 [f2fs]
f2fs_do_write_data_page+0x3f8/0x660 [f2fs]
f2fs_write_single_data_page+0x5bb/0x7a0 [f2fs]
f2fs_write_cache_pages+0x3da/0xbe0 [f2fs]
...
It is possible that other threads have added this fio to io->bio
and submitted the io->bio before entering f2fs_submit_page_write().
At this point io->bio = NULL.
If is_end_zone_blkaddr(sbi, fio->new_blkaddr) of this fio is true,
then an NULL pointer dereference error occurs at bio_get(io->bio).
The original code for determining zone end was after "out:",
which would have missed some fio who is zone end. I've moved
this code before "skip:" to make sure it's done for each fio.

Fixes: e067dc3c6b9c ("f2fs: maintain six open zones for zoned devices")
Signed-off-by: Wenjie Qi <qwjhust@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: zone: fix to wait completion of last bio in zone correctly

It needs to check last zone_pending_bio and wait IO completion before
traverse next fio in io->io_list, otherwise, bio in next zone may be
submitted before all IO completion in current zone.

Fixes: e067dc3c6b9c ("f2fs: maintain six open zones for zoned devices")
Cc: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to avoid inconsistence bewteen i_blocks and dnode

In reserve_compress_blocks(), we update blkaddrs of dnode in prior to
inc_valid_block_count(), it may cause inconsistent status bewteen
i_blocks and blkaddrs once inc_valid_block_count() fails.

To fix this issue, it needs to reverse their invoking order.

Fixes: c75488fb4d82 ("f2fs: introduce F2FS_IOC_RESERVE_COMPRESS_BLOCKS")
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to cover normal cluster write with cp_rwsem

When we overwrite compressed cluster w/ normal cluster, we should
not unlock cp_rwsem during f2fs_write_raw_pages(), otherwise data
will be corrupted if partial blocks were persisted before CP & SPOR,
due to cluster metadata wasn't updated atomically.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to guarantee persisting compressed blocks by CP

If data block in compressed cluster is not persisted with metadata
during checkpoint, after SPOR, the data may be corrupted, let's
guarantee to write compressed page by checkpoint.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

block: remove support for the host aware zone model

When zones were first added the SCSI and ATA specs, two different
models were supported (in addition to the drive managed one that
is invisible to the host):

- host managed where non-conventional zones there is strict requirement
to write at the write pointer, or else an error is returned
- host aware where a write point is maintained if writes always happen
at it, otherwise it is left in an under-defined state and the
sequential write preferred zones behave like conventional zones
(probably very badly performing ones, though)

Not surprisingly this lukewarm model didn't prove to be very useful and
was finally removed from the ZBC and SBC specs (NVMe never implemented
it). Due to to the easily disappearing write pointer host software
could never rely on the write pointer to actually be useful for say
recovery.

Fortunately only a few HDD prototypes shipped using this model which
never made it to mass production. Drop the support before it is too
late. Note that any such host aware prototype HDD can still be used
with Linux as we'll now treat it as a conventional HDD.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20231217165359.604246-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: fix to wait on block writeback for post_read case

If inode is compressed, but not encrypted, it missed to call
f2fs_wait_on_block_writeback() to wait for GCed page writeback
in IPU write path.

Thread A GC-Thread
- f2fs_gc
- do_garbage_collect
- gc_data_segment
- move_data_block
- f2fs_submit_page_write
migrate normal cluster's block via
meta_inode's page cache
- f2fs_write_single_data_page
- f2fs_do_write_data_page
- f2fs_inplace_write_data
- f2fs_submit_page_bio

IRQ
- f2fs_read_end_io
IRQ
old data overrides new data due to
out-of-order GC and common IO.
- f2fs_read_end_io

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce f2fs_invalidate_internal_cache() for cleanup

Just cleanup, no logic changes.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: update blkaddr in __set_data_blkaddr() for cleanup

This patch allows caller to pass blkaddr to f2fs_set_data_blkaddr()
and let __set_data_blkaddr() inside f2fs_set_data_blkaddr() to update
dn->data_blkaddr w/ last value of blkaddr.

Just cleanup, no logic changes.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce get_dnode_addr() to clean up codes

Just cleanup, no logic changes.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: delete obsolete FI_DROP_CACHE

FI_DROP_CACHE was introduced in commit 1e84371ffeef ("f2fs: change
atomic and volatile write policies") for volatile write feature,
after commit 7bc155fec5b3 ("f2fs: kill volatile write support"),
we won't support volatile write, let's delete related codes.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: delete obsolete FI_FIRST_BLOCK_WRITTEN

Commit 3c6c2bebef79 ("f2fs: avoid punch_hole overhead when releasing
volatile data") introduced FI_FIRST_BLOCK_WRITTEN as below reason:

This patch is to avoid some punch_hole overhead when releasing volatile
data. If volatile data was not written yet, we just can make the first
page as zero.

After commit 7bc155fec5b3 ("f2fs: kill volatile write support"), we
won't support volatile write, but it missed to remove obsolete
FI_FIRST_BLOCK_WRITTEN, delete it in this patch.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use shared inode lock during f2fs_fiemap()

f2fs_fiemap() will only traverse metadata of inode, let's use shared
inode lock for it to avoid unnecessary race on inode lock.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Support Block Size == Page Size

This allows f2fs to support cases where the block size = page size for
both 4K and 16K block sizes. Other sizes should work as well, should the
need arise. This does not currently support 4K Block size filesystems if
the page size is 16K.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to avoid fragment w/ OPU during f2fs_ioc_compress_file()

If file has both cold and compress flag, during f2fs_ioc_compress_file(),
f2fs will trigger IPU for non-compress cluster and OPU for compress
cluster, so that, data of the file may be fragmented.

Fix it by always triggering OPU for IOs from user mode compression.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: do sanity check on cluster when CONFIG_F2FS_CHECK_FS is on

This patch covers sanity check logic on cluster w/ CONFIG_F2FS_CHECK_FS,
otherwise, there will be performance regression while querying cluster
mapping info.

Callers of f2fs_is_compressed_cluster() only care about whether cluster
is compressed or not, rather than # of valid blocks in compressed cluster,
so, let's adjust f2fs_is_compressed_cluster()'s logic according to
caller's requirement.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to avoid use-after-free on dic

Call trace:
__memcpy+0x128/0x250
f2fs_read_multi_pages+0x940/0xf7c
f2fs_mpage_readpages+0x5a8/0x624
f2fs_readahead+0x5c/0x110
page_cache_ra_unbounded+0x1b8/0x590
do_sync_mmap_readahead+0x1dc/0x2e4
filemap_fault+0x254/0xa8c
f2fs_filemap_fault+0x2c/0x104
__do_fault+0x7c/0x238
do_handle_mm_fault+0x11bc/0x2d14
do_mem_abort+0x3a8/0x1004
el0_da+0x3c/0xa0
el0t_64_sync_handler+0xc4/0xec
el0t_64_sync+0x1b4/0x1b8

In f2fs_read_multi_pages(), once f2fs_decompress_cluster() was called if
we hit cached page in compress_inode's cache, dic may be released, it needs
break the loop rather than continuing it, in order to avoid accessing
invalid dic pointer.

Fixes: 6ce19aff0b8c ("f2fs: compress: add compress_inode to cache compressed blocks")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix deadloop in f2fs_write_cache_pages()

With below mount option and testcase, it hangs kernel.

1. mount -t f2fs -o compress_log_size=5 /dev/vdb /mnt/f2fs
2. touch /mnt/f2fs/file
3. chattr +c /mnt/f2fs/file
4. dd if=/dev/zero of=/mnt/f2fs/file bs=1MB count=1
5. sync
6. dd if=/dev/zero of=/mnt/f2fs/file bs=111 count=11 conv=notrunc
7. sync

INFO: task sync:4788 blocked for more than 120 seconds.
Not tainted 6.5.0-rc1+ #322
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:sync state:D stack:0 pid:4788 ppid:509 flags:0x00000002
Call Trace:
<TASK>
__schedule+0x335/0xf80
schedule+0x6f/0xf0
wb_wait_for_completion+0x5e/0x90
sync_inodes_sb+0xd8/0x2a0
sync_inodes_one_sb+0x1d/0x30
iterate_supers+0x99/0xf0
ksys_sync+0x46/0xb0
__do_sys_sync+0x12/0x20
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x6e/0xd8

The reason is f2fs_all_cluster_page_ready() assumes that pages array should
cover at least one cluster, otherwise, it will always return false, result
in deadloop.

By default, pages array size is 16, and it can cover the case cluster_size
is equal or less than 16, for the case cluster_size is larger than 16, let's
allocate memory of pages array dynamically.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix error path of f2fs_submit_page_read()

In error path of f2fs_submit_page_read(), it missed to call
iostat_update_and_unbind_ctx() and free bio_post_read_ctx, fix it.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: increase usage of folio_next_index() helper

Simplify code pattern of 'folio->index + folio_nr_pages(folio)' by using
the existing helper folio_next_index().

Signed-off-by: Minjie Du <duminjie@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: get out of a repeat loop when getting a locked data page

https://bugzilla.kernel.org/show_bug.cgi?id=216050

Somehow we're getting a page which has a different mapping.
Let's avoid the infinite loop.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: set FMODE_CAN_ODIRECT instead of a dummy direct_IO method

Since commit a2ad63daa88b ("VFS: add FMODE_CAN_ODIRECT file flag") file
systems can just set the FMODE_CAN_ODIRECT flag at open time instead of
wiring up a dummy direct_IO method to indicate support for direct I/O.

Do that for f2fs so that noop_direct_IO can eventually be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix potential deadlock due to unpaired node_write lock use

If S_NOQUOTA is cleared from inode during data page writeback of quota
file, it may miss to unlock node_write lock, result in potential
deadlock, fix to use the lock in paired.

Kworker Thread
- writepage
if (IS_NOQUOTA())
f2fs_down_read(&sbi->node_write);
- vfs_cleanup_quota_inode
- inode->i_flags &= ~S_NOQUOTA;
if (IS_NOQUOTA())
f2fs_up_read(&sbi->node_write);

Fixes: 79963d967b49 ("f2fs: shrink node_write lock coverage")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: maintain six open zones for zoned devices

To keep six open zone constraints, make them not to be open over six
open zones.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove redundant goto statement in f2fs_read_single_page()

After the commit "0a4ee518185", this "goto" statement was redundant,
remote it for clean code.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support errors=remount-ro|continue|panic mountoption

This patch supports errors=remount-ro|continue|panic mount option
for f2fs.

f2fs behaves as below in three different modes:
mode continue remount-ro panic
access ops normal noraml N/A
syscall errors -EIO -EROFS N/A
mount option rw ro N/A
pending dir write keep keep N/A
pending non-dir write drop keep N/A
pending node write drop keep N/A
pending meta write keep keep N/A

By default it uses "continue" mode.

[Yangtao helps to clean up function's name]
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use cow inode data when updating atomic write

Need to use cow inode data content instead of the one in the original
inode, when we try to write the already updated atomic write files.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: relax sanity check if checkpoint is corrupted

1. extent_cache
- let's drop the largest extent_cache
2. invalidate_block
- don't show the warnings

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

We have maintain PagePrivate and page_private and page reference
w/ {set,clear}_page_private_*, it doesn't need to call
folio_detach_private() in the end of .invalidate_folio and
.release_folio, remove it and use f2fs_bug_on instead.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to drop all dirty pages during umount() if cp_error is set

xfstest generic/361 reports a bug as below:

f2fs_bug_on(sbi, sbi->fsync_node_num);

kernel BUG at fs/f2fs/super.c:1627!
RIP: 0010:f2fs_put_super+0x3a8/0x3b0
Call Trace:
generic_shutdown_super+0x8c/0x1b0
kill_block_super+0x2b/0x60
kill_f2fs_super+0x87/0x110
deactivate_locked_super+0x39/0x80
deactivate_super+0x46/0x50
cleanup_mnt+0x109/0x170
__cleanup_mnt+0x16/0x20
task_work_run+0x65/0xa0
exit_to_user_mode_prepare+0x175/0x190
syscall_exit_to_user_mode+0x25/0x50
do_syscall_64+0x4c/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc

During umount(), if cp_error is set, f2fs_wait_on_all_pages() should
not stop waiting all F2FS_WB_CP_DATA pages to be writebacked, otherwise,
fsync_node_num can be non-zero after f2fs_wait_on_all_pages() causing
this bug.

In this case, to avoid deadloop in f2fs_wait_on_all_pages(), it needs
to drop all dirty pages rather than redirtying them.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to avoid use-after-free for cached IPU bio

xfstest generic/019 reports a bug:

kernel BUG at mm/filemap.c:1619!
RIP: 0010:folio_end_writeback+0x8a/0x90
Call Trace:
end_page_writeback+0x1c/0x60
f2fs_write_end_io+0x199/0x420
bio_endio+0x104/0x180
submit_bio_noacct+0xa5/0x510
submit_bio+0x48/0x80
f2fs_submit_write_bio+0x35/0x300
f2fs_submit_merged_ipu_write+0x2a0/0x2b0
f2fs_write_single_data_page+0x838/0x8b0
f2fs_write_cache_pages+0x379/0xa30
f2fs_write_data_pages+0x30c/0x340
do_writepages+0xd8/0x1b0
__writeback_single_inode+0x44/0x370
writeback_sb_inodes+0x233/0x4d0
__writeback_inodes_wb+0x56/0xf0
wb_writeback+0x1dd/0x2d0
wb_workfn+0x367/0x4a0
process_one_work+0x21d/0x430
worker_thread+0x4e/0x3c0
kthread+0x103/0x130
ret_from_fork+0x2c/0x50

The root cause is: after cp_error is set, f2fs_submit_merged_ipu_write()
in f2fs_write_single_data_page() tries to flush IPU bio in cache, however
f2fs_submit_merged_ipu_write() missed to check validity of @bio parameter,
result in submitting random cached bio which belong to other IO context,
then it will cause use-after-free issue, fix it by adding additional
validity check.

Fixes: 0b20fcec8651 ("f2fs: cache global IPU bio")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove else in f2fs_write_cache_pages()

As Christoph Hellwig point out:

Please avoid the else by doing the goto in the branch.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: convert to use bitmap API

Let's use BIT() and GENMASK() instead of open it.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix typos in comments

This patch is to fix typos in f2fs files.

Signed-off-by: Jinyoung Choi <j-young.choi@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix kernel crash due to null io->bio

We should return when io->bio is null before doing anything. Otherwise, panic.

BUG: kernel NULL pointer dereference, address: 0000000000000010
RIP: 0010:__submit_merged_write_cond+0x164/0x240 [f2fs]
Call Trace:
<TASK>
f2fs_submit_merged_write+0x1d/0x30 [f2fs]
commit_checkpoint+0x110/0x1e0 [f2fs]
f2fs_write_checkpoint+0x9f7/0xf00 [f2fs]
? __pfx_issue_checkpoint_thread+0x10/0x10 [f2fs]
__checkpoint_and_complete_reqs+0x84/0x190 [f2fs]
? preempt_count_add+0x82/0xc0
? __pfx_issue_checkpoint_thread+0x10/0x10 [f2fs]
issue_checkpoint_thread+0x4c/0xf0 [f2fs]
? __pfx_autoremove_wake_function+0x10/0x10
kthread+0xff/0x130
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>

Cc: stable@vger.kernel.org # v5.18+
Fixes: 64bf0eef0171 ("f2fs: pass the bio operation to bio_alloc_bioset")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use iostat_lat_type directly as a parameter in the iostat_update_and_unbind_ctx()

Convert to use iostat_lat_type as parameter instead of raw number.
BTW, move NUM_PREALLOC_IOSTAT_CTXS to the header file, adjust
iostat_lat[{0,1,2}] to iostat_lat[{READ_IO,WRITE_SYNC_IO,WRITE_ASYNC_IO}]
in tracepoint function, and rename iotype to page_type to match the definition.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix cgroup writeback accounting with fs-layer encryption

When writing a page from an encrypted file that is using
filesystem-layer encryption (not inline encryption), f2fs encrypts the
pagecache page into a bounce page, then writes the bounce page.

It also passes the bounce page to wbc_account_cgroup_owner(). That's
incorrect, because the bounce page is a newly allocated temporary page
that doesn't have the memory cgroup of the original pagecache page.
This makes wbc_account_cgroup_owner() not account the I/O to the owner
of the pagecache page as it should.

Fix this by always passing the pagecache page to
wbc_account_cgroup_owner().

Fixes: 578c647879f7 ("f2fs: implement cgroup writeback support")
Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: reduce stack memory cost by using bitfield in struct f2fs_io_info

This patch tries to use bitfield in struct f2fs_io_info to improve
memory usage.

struct f2fs_io_info {
...
unsigned int need_lock:8; /* indicate we need to lock cp_rwsem */
unsigned int version:8; /* version of the node */
unsigned int submitted:1; /* indicate IO submission */
unsigned int in_list:1; /* indicate fio is in io_list */
unsigned int is_por:1; /* indicate IO is from recovery or not */
unsigned int retry:1; /* need to reallocate block address */
unsigned int encrypted:1; /* indicate file is encrypted */
unsigned int post_read:1; /* require post read */
...
};

After this patch, size of struct f2fs_io_info reduces from 136 to 120.

[Nathan: fix a compile warning (single-bit-bitfield-constant-conversion)]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: merge f2fs_show_injection_info() into time_to_inject()

There is no need to additionally use f2fs_show_injection_info()
to output information. Concatenate time_to_inject() and
__time_to_inject() via a macro. In the new __time_to_inject()
function, pass in the caller function name and parent function.

In this way, we no longer need the f2fs_show_injection_info() function,
and let's remove it.

Suggested-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid to check PG_error flag

After below changes:
commit 14db0b3c7b83 ("fscrypt: stop using PG_error to track error status")
commit 98dc08bae678 ("fsverity: stop using PG_error to track error status")

There is no place in f2fs we will set PG_error flag in page, let's remove
other PG_error usage in f2fs, as a step towards freeing the PG_error flag
for other uses.

Cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce IS_F2FS_IPU_* macro

IS_F2FS_IPU_* macro can be used to identify whether
f2fs ipu related policies are enabled.

BTW, convert to use BIT() instead of open code.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: refactor the hole reporting and allocation logic in f2fs_map_blocks

Add a is_hole local variable to figure out if the block number might need
allocation, and untangle to logic to report the hole or fill it with a
block allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: factor out a f2fs_map_no_dnode

Factor out a helper to return a hole when no dnode was found.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: factor a f2fs_map_blocks_cached helper

Add a helper to deal with everything needed to return a f2fs_map_blocks
structure based on a lookup in the extent cache.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove the create argument to f2fs_map_blocks

The create argument is always identicaly to map->m_may_create, so use
that consistently.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove f2fs_get_block

Fold f2fs_get_block into the two remaining callers to simplify the
call chain a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: simplify __allocate_data_block

Just use a simple if block for the conditional call to
inc_valid_block_count.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: reflow prepare_write_begin

Reflow prepare_write_begin so that it reads more straight forward,
and so that there is one place that does an extent cache lookup
instead of three, two of which are hidden in f2fs_get_block calls.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: f2fs_do_map_lock

Split f2fs_do_map_lock into a lock and unlock helper to make the code
using it easier to read.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add a f2fs_get_block_locked helper

This allows to keep the f2fs_do_map_lock based locking scheme
private to data.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add a f2fs_lookup_extent_cache_block helper

All but three callers of f2fs_lookup_extent_cache just want the block
address. Add a small helper to simplify them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: split __submit_bio

Split __submit_bio into one function each for reads and writes, and a
helper for aligning writes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: rename F2FS_MAP_UNWRITTEN to F2FS_MAP_DELALLOC

NEW_ADDR blocks are purely in-memory preallocated blocks, and thus
equivalent to what the core FS code calls delayed allocations, and not
unwritten extents which do have on-disk blocks allocated from which
reads always return zeroes until they are converted to written status.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: don't rely on F2FS_MAP_* in f2fs_iomap_begin

When testing with a mixed zoned / convention device combination, there
are regular but not 100% reproducible failures in xfstests generic/113
where the __is_valid_data_blkaddr assert hits due to finding a hole.

This seems to be because f2fs_map_blocks can set this flag on a hole
when it was found in the extent cache.

Rework f2fs_iomap_begin to just check the special block numbers directly.
This has the added benefits of the WARN_ON showing which invalid block
address we found, and being properly error out on delalloc blocks that
are confusingly called unwritten but not actually suitable for direct
I/O.

Fixes: 1517c1a7a445 ("f2fs: implement iomap operations")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to call clear_page_private_reference in .{release,invalid}_folio

b763f3bedc2d ("f2fs: restructure f2fs page.private layout") missed
to call clear_page_private_reference() in .{release,invalid}_folio,
fix it, though it's not a big deal since folio_detach_private() was
called to clear all privae info and reference count in the page.

BTW, remove page_private_reference() definition as it never be used.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: convert f2fs_write_cache_pages() to use filemap_get_folios_tag()

Convert the function to use a folio_batch instead of pagevec. This is in
preparation for the removal of find_get_pages_range_tag().

Also modified f2fs_all_cluster_page_ready to take in a folio_batch instead
of pagevec. This does NOT support large folios. The function currently
only utilizes folios of size 1 so this shouldn't cause any issues right
now.

This version of the patch limits the number of pages fetched to
F2FS_ONSTACK_PAGES. If that ever happens, update the start index here
since filemap_get_folios_tag() updates the index to be after the last
found folio, not necessarily the last used page.

Link: https://lkml.kernel.org/r/20230104211448.4804-15-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

f2fs: simplify f2fs_readpage_limit()

Now that the implementation of FS_IOC_ENABLE_VERITY has changed to not
involve reading back Merkle tree blocks that were previously written,
there is no need for f2fs_readpage_limit() to allow for this case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://lore.kernel.org/r/20221223203638.41293-10-ebiggers@kernel.org

f2fs: initialize extent_cache parameter

This can avoid confusing tracepoint values.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: refactor extent_cache to support for read and more

This patch prepares extent_cache to be ready for addition.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: do some cleanup for f2fs module init

Just for cleanup, no functional changes.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce F2FS_IOC_START_ATOMIC_REPLACE

introduce a new ioctl to replace the whole content of a file atomically,
which means it induces truncate and content update at the same time.
We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with
F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with
F2FS_IOC_ABORT_ATOMIC_WRITE.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: optimize iteration over sparse directories

Wei Chen reports a kernel bug as blew:

INFO: task syz-executor.0:29056 blocked for more than 143 seconds.
Not tainted 5.15.0-rc5 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:14632 pid:29056 ppid: 6574 flags:0x00000004
Call Trace:
__schedule+0x4a1/0x1720
schedule+0x36/0xe0
rwsem_down_write_slowpath+0x322/0x7a0
fscrypt_ioctl_set_policy+0x11f/0x2a0
__f2fs_ioctl+0x1a9f/0x5780
f2fs_ioctl+0x89/0x3a0
__x64_sys_ioctl+0xe8/0x140
do_syscall_64+0x34/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae

Eric did some investigation on this issue, quoted from reply of Eric:

"Well, the quality of this bug report has a lot to be desired (not on
upstream kernel, reproducer is full of totally irrelevant stuff, not
sent to the mailing list of the filesystem whose disk image is being
fuzzed, etc.). But what is going on is that f2fs_empty_dir() doesn't
consider the case of a directory with an extremely large i_size on a
malicious disk image.

Specifically, the reproducer mounts an f2fs image with a directory
that has an i_size of 14814520042850357248, then calls
FS_IOC_SET_ENCRYPTION_POLICY on it.

That results in a call to f2fs_empty_dir() to check whether the
directory is empty. f2fs_empty_dir() then iterates through all
3616826182336513 blocks the directory allegedly contains to check
whether any contain anything. i_rwsem is held during this, so
anything else that tries to take it will hang."

In order to solve this issue, let's use f2fs_get_next_page_offset()
to speed up iteration by skipping holes for all below functions:
- f2fs_empty_dir
- f2fs_readdir
- find_in_level

The way why we can speed up iteration was described in
'commit 3cf4574705b4 ("f2fs: introduce get_next_page_offset to speed
up SEEK_DATA")'.

Meanwhile, in f2fs_empty_dir(), let's use f2fs_find_data_page()
instead f2fs_get_lock_data_page(), due to i_rwsem was held in
caller of f2fs_empty_dir(), there shouldn't be any races, so it's
fine to not lock dentry page during lookuping dirents in the page.

Link: https://lore.kernel.org/lkml/536944df-a0ae-1dd8-148f-510b476e1347@kernel.org/T/
Reported-by: Wei Chen <harperchen1110@gmail.com>
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fsverity: stop using PG_error to track error status

As a step towards freeing the PG_error flag for other uses, change ext4
and f2fs to stop using PG_error to track verity errors. Instead, if a
verity error occurs, just mark the whole bio as failed. The coarser
granularity isn't really a problem since it isn't any worse than what
the block layer provides, and errors from a multi-page readahead aren't
reported to applications unless a single-page read fails too.

f2fs supports compression, which makes the f2fs changes a bit more
complicated than desired, but the basic premise still works.

Note: there are still a few uses of PageError in f2fs, but they are on
the write path, so they are unrelated and this patch doesn't touch them.

Reviewed-by: Chao Yu <chao@kernel.org>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221129070401.156114-1-ebiggers@kernel.org

f2fs: account swapfile inodes

In order to check count of opened swapfile inodes.

Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support recording errors into superblock

This patch supports to record detail reason of FSCORRUPTED error into
f2fs_super_block.s_errors[].

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support recording stop_checkpoint reason into super_block

This patch supports to record stop_checkpoint error into
f2fs_super_block.s_stop_reason[].

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove the unnecessary check in f2fs_xattr_fiemap

Whehter or not error occurs, checking "err == 1" is unnecessary
in f2fs_xattr_fiemap(), and just remove it here.

Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to account FS_CP_DATA_IO correctly

f2fs_inode_info.cp_task was introduced for FS_CP_DATA_IO accounting
since commit b0af6d491a6b ("f2fs: add app/fs io stat").

However, cp_task usage coverage has been increased due to below
commits:
commit 040d2bb318d1 ("f2fs: fix to avoid deadloop if data_flush is on")
commit 186857c5a14a ("f2fs: fix potential recursive call when enabling data_flush")

So that, if data_flush mountoption is on, when data flush was
triggered from background, the IO from data flush will be accounted
as checkpoint IO type incorrectly.

In order to fix this issue, this patch splits cp_task into two:
a) cp_task: used for IO accounting
b) wb_task: used to avoid deadlock

Fixes: 040d2bb318d1 ("f2fs: fix to avoid deadloop if data_flush is on")
Fixes: 186857c5a14a ("f2fs: fix potential recursive call when enabling data_flush")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: code clean and fix a type error

ERROR: code indent should use tabs where possible
ERROR: spaces required around that ':'
ERROR: incorrect tab

Found serveral code type errors when review the code and fix it.
There is no function change.

Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: let FI_OPU_WRITE override FADVISE_COLD_BIT

Cold files may be fragmented due to SSR, defragment is needed as
sequential reads are dominant scenarios of these files. FI_OPU_WRITE
should override FADVISE_COLD_BIT to avoid defragment fails.

Signed-off-by: Weichao Guo <guoweichao@oppo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix wrong dirty page count when race between mmap and fallocate.

This is a BUG_ON issue as follows when running xfstest-generic-503:
WARNING: CPU: 21 PID: 1385 at fs/f2fs/inode.c:762 f2fs_evict_inode+0x847/0xaa0
Modules linked in:
CPU: 21 PID: 1385 Comm: umount Not tainted 5.19.0-rc5+ #73
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014

Call Trace:
evict+0x129/0x2d0
dispose_list+0x4f/0xb0
evict_inodes+0x204/0x230
generic_shutdown_super+0x5b/0x1e0
kill_block_super+0x29/0x80
kill_f2fs_super+0xe6/0x140
deactivate_locked_super+0x44/0xc0
deactivate_super+0x79/0x90
cleanup_mnt+0x114/0x1a0
__cleanup_mnt+0x16/0x20
task_work_run+0x98/0x100
exit_to_user_mode_prepare+0x3d0/0x3e0
syscall_exit_to_user_mode+0x12/0x30
do_syscall_64+0x42/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0

Function flow analysis when BUG occurs:
f2fs_fallocate mmap
do_page_fault
pte_spinlock // ---lock_pte
do_wp_page
wp_page_shared
pte_unmap_unlock // unlock_pte
do_page_mkwrite
f2fs_vm_page_mkwrite
down_read(invalidate_lock)
lock_page
if (PageMappedToDisk(page))
goto out;
// set_page_dirty --NOT RUN
out: up_read(invalidate_lock);
finish_mkwrite_fault // unlock_pte
f2fs_collapse_range
down_write(i_mmap_sem)
truncate_pagecache
unmap_mapping_pages
i_mmap_lock_write // down_write(i_mmap_rwsem)
......
zap_pte_range
pte_offset_map_lock // ---lock_pte
set_page_dirty
f2fs_dirty_data_folio
if (!folio_test_dirty(folio)) {
fault_dirty_shared_page
set_page_dirty
f2fs_dirty_data_folio
if (!folio_test_dirty(folio)) {
filemap_dirty_folio
f2fs_update_dirty_folio // ++
}
unlock_page
filemap_dirty_folio
f2fs_update_dirty_folio // page count++
}
pte_unmap_unlock // --unlock_pte
i_mmap_unlock_write // up_write(i_mmap_rwsem)
truncate_inode_pages
up_write(i_mmap_sem)

When race happens between mmap-do_page_fault-wp_page_shared and
fallocate-truncate_pagecache-zap_pte_range, the zap_pte_range calls
function set_page_dirty without page lock. Besides, though
truncate_pagecache has immap and pte lock, wp_page_shared calls
fault_dirty_shared_page without any. In this case, two threads race
in f2fs_dirty_data_folio function. Page is set to dirty only ONCE,
but the count is added TWICE by calling filemap_dirty_folio.
Thus the count of dirty page cannot accord with the real dirty pages.

Following is the solution to in case of race happens without any lock.
Since folio_test_set_dirty in filemap_dirty_folio is atomic, judge return
value will not be at risk of race.

Signed-off-by: Shuqi Zhang <zhangshuqi3@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: iostat: support accounting compressed IO

Previously, we supported to account FS_CDATA_READ_IO type IO only,
in this patch, it adds to account more type IO for compressed file:
- APP_BUFFERED_CDATA_IO
- APP_MAPPED_CDATA_IO
- FS_CDATA_IO
- APP_BUFFERED_CDATA_READ_IO
- APP_MAPPED_CDATA_READ_IO

Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fscrypt: stop using PG_error to track error status

As a step towards freeing the PG_error flag for other uses, change ext4
and f2fs to stop using PG_error to track decryption errors. Instead, if
a decryption error occurs, just mark the whole bio as failed. The
coarser granularity isn't really a problem since it isn't any worse than
what the block layer provides, and errors from a multi-page readahead
aren't reported to applications unless a single-page read fails too.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <chao@kernel.org> # for f2fs part
Link: https://lore.kernel.org/r/20220815235052.86545-2-ebiggers@kernel.org

f2fs: use onstack pages instead of pvec

Since pvec have 15 pages, it not a multiple of 4, when write compressed
pages, write in 64K as a unit, it will call pagevec_lookup_range_tag
agagin, sometimes this will take a lot of time.
Use onstack pages instead of pvec to mitigate this problem.

Signed-off-by: Fengnan Chang <fengnanchang@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: intorduce f2fs_all_cluster_page_ready

When write total cluster, all pages is uptodate, there is not need to call
f2fs_prepare_compress_overwrite, intorduce f2fs_all_cluster_page_ready
to avoid this.

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: handle decompress only post processing in softirq

Now decompression is being handled in workqueue and it makes read I/O
latency non-deterministic, because of the non-deterministic scheduling
nature of workqueues. So, I made it handled in softirq context only if
possible, not in low memory devices, since this modification will
maintain decompresion related memory a little longer.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce sysfs atomic write statistics

introduce the below 4 new sysfs node for atomic write statistics.
- current_atomic_write: the total current atomic write block count,
which is not committed yet.
- peak_atomic_write: the peak value of total current atomic write block
count after boot.
- committed_atomic_block: the accumulated total committed atomic write
block count after boot.
- revoked_atomic_block: the accumulated total revoked atomic write block
count after boot.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: invalidate meta pages only for post_read required inode

After commit e3b49ea36802 ("f2fs: invalidate META_MAPPING before
IPU/DIO write"), invalidate_mapping_pages() will be called to
avoid race condition in between IPU/DIO and readahead for GC.

However, readahead flow is only used for post_read required inode,
so this patch adds check condition to avoids unnecessary page cache
invalidating for non-post_read inode.

Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to invalidate META_MAPPING before DIO write

Quoted from commit e3b49ea36802 ("f2fs: invalidate META_MAPPING before
IPU/DIO write")

"
Encrypted pages during GC are read and cached in META_MAPPING.
However, due to cached pages in META_MAPPING, there is an issue where
newly written pages are lost by IPU or DIO writes.

Thread A - f2fs_gc() Thread B
/* phase 3 */
down_write(i_gc_rwsem)
ra_data_block() ---- (a)
up_write(i_gc_rwsem)
f2fs_direct_IO() :
- down_read(i_gc_rwsem)
- __blockdev_direct_io()
- get_data_block_dio_write()
- f2fs_dio_submit_bio() ---- (b)
- up_read(i_gc_rwsem)
/* phase 4 */
down_write(i_gc_rwsem)
move_data_block() ---- (c)
up_write(i_gc_rwsem)

(a) In phase 3 of f2fs_gc(), up-to-date page is read from storage and
cached in META_MAPPING.
(b) In thread B, writing new data by IPU or DIO write on same blkaddr as
read in (a). cached page in META_MAPPING become out-dated.
(c) In phase 4 of f2fs_gc(), out-dated page in META_MAPPING is copied to
new blkaddr. In conclusion, the newly written data in (b) is lost.

To address this issue, invalidating pages in META_MAPPING before IPU or
DIO write.
"

In previous commit, we missed to cover extent cache hit case, and passed
wrong value for parameter @end of invalidate_mapping_pages(), fix both
issues.

Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC")
Fixes: e3b49ea36802 ("f2fs: invalidate META_MAPPING before IPU/DIO write")
Cc: Hyeong-Jun Kim <hj514.kim@samsung.com>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Convert to filemap_migrate_folio()

filemap_migrate_folio() fits f2fs's needs perfectly.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Chao Yu <chao@kernel.org>

fs/f2fs: 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.

Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-53-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: add f2fs_init_write_merge_io function

Almost all other initialization of variables in f2fs_fill_super are
extraced to a single function. Also do it for write_io[], which can
make code more clean.

This patch just refactors the code, theres no functional change.

Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Reviewed-by: Chao Yu <chao@kernel.org>
[Jaegeuk Kim: clean up]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: kill volatile write support

There's no user, since all can use atomic writes simply.
Let's kill it.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: change the current atomic write way

Current atomic write has three major issues like below.
- keeps the updates in non-reclaimable memory space and they are even
hard to be migrated, which is not good for contiguous memory
allocation.
- disk spaces used for atomic files cannot be garbage collected, so
this makes it difficult for the filesystem to be defragmented.
- If atomic write operations hit the threshold of either memory usage
or garbage collection failure count, All the atomic write operations
will fail immediately.

To resolve the issues, I will keep a COW inode internally for all the
updates to be flushed from memory, when we need to flush them out in a
situation like high memory pressure. These COW inodes will be tagged
as orphan inodes to be reclaimed in case of sudden power-cut or system
failure during atomic writes.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Convert to release_folio

While converting f2fs_release_page() to f2fs_release_folio(), cache the
sb_info so we don't need to retrieve it twice, and remove the redundant
call to set_page_private(). The use of folios should be pushed further
into f2fs from here.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

f2fs: Convert f2fs to read_folio

This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

fs: Remove flags parameter from aops->write_begin

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

f2fs: keep io_flags to avoid IO split due to different op_flags in two fio holders

Let's attach io_flags to bio only, so that we can merge IOs given original
io_flags only.

Fixes: 64bf0eef0171 ("f2fs: pass the bio operation to bio_alloc_bioset")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Correct f2fs_dirty_data_folio() conversion

I got the return value wrong. Very little checks the return value
from set_page_dirty(), so nobody noticed during testing.

Fixes: 4f5e34f71318 ("f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>

fs: Remove ->readpages address space operation

All filesystems have now been converted to use ->readahead, so
remove the ->readpages operation and fix all the comments that
used to refer to it.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>

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>

f2fs: replace congestion_wait() calls with io_schedule_timeout()

As congestion is no longer tracked, congestion_wait() is effectively
equivalent to io_schedule_timeout().

So introduce f2fs_io_schedule_timeout() which sets TASK_UNINTERRUPTIBLE
and call that instead.

Link: https://lkml.kernel.org/r/164549983744.9187.6425865370954230902.stgit@noble.brown
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: fix compressed file start atomic write may cause data corruption

When compressed file has blocks, f2fs_ioc_start_atomic_write will succeed,
but compressed flag will be remained in inode. If write partial compreseed
cluster and commit atomic write will cause data corruption.

This is the reproduction process:
Step 1:
create a compressed file ,write 64K data , call fsync(), then the blocks
are write as compressed cluster.
Step2:
iotcl(F2FS_IOC_START_ATOMIC_WRITE) --- this should be fail, but not.
write page 0 and page 3.
iotcl(F2FS_IOC_COMMIT_ATOMIC_WRITE) -- page 0 and 3 write as normal file,
Step3:
drop cache.
read page 0-4 -- Since page 0 has a valid block address, read as
non-compressed cluster, page 1 and 2 will be filled with compressed data
or zero.

The root cause is, after commit 7eab7a696827 ("f2fs: compress: remove
unneeded read when rewrite whole cluster"), in step 2, f2fs_write_begin()
only set target page dirty, and in f2fs_commit_inmem_pages(), we will write
partial raw pages into compressed cluster, result in corrupting compressed
cluster layout.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Fixes: 7eab7a696827 ("f2fs: compress: remove unneeded read when rewrite whole cluster")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio

Removes several calls to __set_page_dirty_nobuffers(). Also turn the
PageSwapCache() case into a BUG() as there's no way for a swapcache page
to make it to a filesystem that doesn't use SWP_FS_OPS.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

f2fs: Convert invalidatepage to invalidate_folio

This is a minimal change which just accepts the new arguments and passes
the single struct page to the functions which do the work. There is
very little progress here toards making f2fs support large folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

f2fs: fix to avoid potential deadlock

Quoted from Jing Xia's report, there is a potential deadlock may happen
between kworker and checkpoint as below:

[T:writeback] [T:checkpoint]
- wb_writeback
- blk_start_plug
bio contains NodeA was plugged in writeback threads
- do_writepages -- sync write inodeB, inc wb_sync_req[DATA]
- f2fs_write_data_pages
- f2fs_write_single_data_page -- write last dirty page
- f2fs_do_write_data_page
- set_page_writeback -- clear page dirty flag and
PAGECACHE_TAG_DIRTY tag in radix tree
- f2fs_outplace_write_data
- f2fs_update_data_blkaddr
- f2fs_wait_on_page_writeback -- wait NodeA to writeback here
- inode_dec_dirty_pages
- writeback_sb_inodes
- writeback_single_inode
- do_writepages
- f2fs_write_data_pages -- skip writepages due to wb_sync_req[DATA]
- wbc->pages_skipped += get_dirty_pages() -- PAGECACHE_TAG_DIRTY is not set but get_dirty_pages() returns one
- requeue_inode -- requeue inode to wb->b_dirty queue due to non-zero.pages_skipped
- blk_finish_plug

Let's try to avoid deadlock condition by forcing unplugging previous bio via
blk_finish_plug(current->plug) once we'v skipped writeback in writepages()
due to valid sbi->wb_sync_req[DATA/NODE].

Fixes: 687de7f1010c ("f2fs: avoid IO split due to mixed WB_SYNC_ALL and WB_SYNC_NONE")
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jing Xia <jing.xia@unisoc.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support direct I/O with fscrypt using blk-crypto

Encrypted files traditionally haven't supported DIO, due to the need to
encrypt/decrypt the data. However, when the encryption is implemented
using inline encryption (blk-crypto) instead of the traditional
filesystem-layer encryption, it is straightforward to support DIO.

Therefore, make f2fs support DIO on files that are using inline
encryption. Since f2fs uses iomap for DIO, and fscrypt support was
already added to iomap DIO, this just requires two small changes:

- Let DIO proceed when supported, by checking fscrypt_dio_supported()
instead of assuming that encrypted files never support DIO.

- In f2fs_iomap_begin(), use fscrypt_limit_io_blocks() to limit the
length of the mapping in the rare case where a DUN discontiguity
occurs in the middle of an extent. The iomap DIO implementation
requires this, since it assumes that it can submit a bio covering (up
to) the whole mapping, without checking fscrypt constraints itself.

Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Link: https://lore.kernel.org/r/20220128233940.79464-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

f2fs: introduce F2FS_IPU_HONOR_OPU_WRITE ipu policy

Once F2FS_IPU_FORCE policy is enabled in some cases:
a) f2fs forces to use F2FS_IPU_FORCE in a small-sized volume
b) user sets F2FS_IPU_FORCE policy via sysfs

Then we may fail to defragment file due to IPU policy check, it doesn't
make sense, let's introduce a new IPU policy to allow OPU during file
defragmentation.

In small-sized volume, let's enable F2FS_IPU_HONOR_OPU_WRITE policy
by default.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: move f2fs to use reader-unfair rwsems

f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reader threads. This prevents significant priority
inversion between low-priority readers that blocked while trying to
acquire the read lock and a second acquisition of the write lock that
might be blocking high priority work.

Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: pass the bio operation to bio_alloc_bioset

Refactor block I/O code so that the bio operation and known flags are set
at bio allocation time. Only the later updated flags are updated on the
fly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220228124123.856027-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: don't pass a bio to f2fs_target_device

Set the bdev at bio allocation time by changing the f2fs_target_device
calling conventions, so that no bio needs to be passed in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220228124123.856027-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: pass a block_device and opf to bio_alloc_bioset

Pass the block_device and operation that we plan to use this bio for to
bio_alloc_bioset to optimize the assigment. NULL/0 can be passed, both
for the passthrough case on a raw request_queue and to temporarily avoid
refactoring some nasty code.

Also move the gfp_mask argument after the nr_vecs argument for a much
more logical calling convention matching what most of the kernel does.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

mm: remove cleancache

Patch series "remove Xen tmem leftovers".

Since the removal of the Xen tmem driver in 2019, the cleancache hooks
are entirely unused, as are large parts of frontswap. This series
against linux-next (with the folio changes included) removes
cleancaches, and cuts down frontswap to the bits actually used by zswap.

This patch (of 13):

The cleancache subsystem is unused since the removal of Xen tmem driver
in commit 814bbf49dcd0 ("xen: remove tmem driver").

[akpm@linux-foundation.org: remove now-unreachable code]

Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de
Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: don't drop compressed page cache in .{invalidate,release}page

For compressed inode, in .{invalidate,release}page, we will call
f2fs_invalidate_compress_pages() to drop all compressed page cache of
current inode.

But we don't need to drop compressed page cache synchronously in
.invalidatepage, because, all trancation paths of compressed physical
block has been covered with f2fs_invalidate_compress_page().

And also we don't need to drop compressed page cache synchronously
in .releasepage, because, if there is out-of-memory, we can count
on page cache reclaim on sbi->compress_inode.

BTW, this patch may fix the issue reported below:

https://lore.kernel.org/linux-f2fs-devel/20211202092812.197647-1-changfengnan@vivo.com/T/#u

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: do not bother checkpoint by f2fs_get_node_info

This patch tries to mitigate lock contention between f2fs_write_checkpoint and
f2fs_get_node_info along with nat_tree_lock.

The idea is, if checkpoint is currently running, other threads that try to grab
nat_tree_lock would be better to wait for checkpoint.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file

Android OTA failed due to SBI_NEED_FSCK flag when pinning the file. Let's avoid
it since we can do in-place-updates.

Cc: stable@vger.kernel.org
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use iomap for direct I/O

Make f2fs_file_read_iter() and f2fs_file_write_iter() use the iomap
direct I/O implementation instead of the fs/direct-io.c one.

The iomap implementation is more efficient, and it also avoids the need
to add new features and optimizations to the old implementation.

This new implementation also eliminates the need for f2fs to hook bio
submission and completion and to allocate memory per-bio. This is
because it's possible to correctly update f2fs's in-flight DIO counters
using __iomap_dio_rw() in combination with an implementation of
iomap_dio_ops::end_io() (as suggested by Christoph Hellwig).

When possible, this new implementation preserves existing f2fs behavior
such as the conditions for falling back to buffered I/O.

This patch has been tested with xfstests by running 'gce-xfstests -c
f2fs -g auto -X generic/017' with and without this patch; no regressions
were seen. (Some tests fail both before and after. generic/017 hangs
both before and after, so it had to be excluded.)

Signed-off-by: Eric Biggers <ebiggers@google.com>
[Jaegeuk Kim: use spin_lock_bh for f2fs_update_iostat in softirq]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: implement iomap operations

Implement 'struct iomap_ops' for f2fs, in preparation for making f2fs
use iomap for direct I/O.

Note that this may be used for other things besides direct I/O in the
future; however, for now I've only tested it for direct I/O.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: do not expose unwritten blocks to user by DIO

DIO preallocates physical blocks before writing data, but if an error occurrs
or power-cut happens, we can see block contents from the disk. This patch tries
to fix it by 1) turning to buffered writes for DIO into holes, 2) truncating
unwritten blocks from error or power-cut.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: rework write preallocations

f2fs_write_begin() assumes that all blocks were preallocated by
default unless FI_NO_PREALLOC is explicitly set. This invites data
corruption, as there are cases in which not all blocks are preallocated.
Commit 47501f87c61a ("f2fs: preallocate DIO blocks when forcing
buffered_io") fixed one case, but there are others remaining.

Fix up this logic by replacing this flag with FI_PREALLOCATED_ALL, which
only gets set if all blocks for the current write were preallocated.

Also clean up f2fs_preallocate_blocks(), move it to file.c, and make it
handle some of the logic that was previously in write_iter() directly.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: reduce one page array alloc and free when write compressed page

Don't alloc new page pointers array to replace old, just use old, introduce
valid_nr_cpages to indicate valid number of page pointers in array, try to
reduce one page array alloc and free when write compress page.

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

mm: introduce memalloc_retry_wait()

Various places in the kernel - largely in filesystems - respond to a
memory allocation failure by looping around and re-trying. Some of
these cannot conveniently use __GFP_NOFAIL, for reasons such as:

- a GFP_ATOMIC allocation, which __GFP_NOFAIL doesn't work on
- a need to check for the process being signalled between failures
- the possibility that other recovery actions could be performed
- the allocation is quite deep in support code, and passing down an
extra flag to say if __GFP_NOFAIL is wanted would be clumsy.

Many of these currently use congestion_wait() which (in almost all
cases) simply waits the given timeout - congestion isn't tracked for
most devices.

It isn't clear what the best delay is for loops, but it is clear that
the various filesystems shouldn't be responsible for choosing a timeout.

This patch introduces memalloc_retry_wait() with takes on that
responsibility. Code that wants to retry a memory allocation can call
this function passing the GFP flags that were used. It will wait
however is appropriate.

For now, it only considers __GFP_NORETRY and whatever
gfpflags_allow_blocking() tests. If blocking is allowed without
__GFP_NORETRY, then alloc_page either made some reclaim progress, or
waited for a while, before failing. So there is no need for much
further waiting. memalloc_retry_wait() will wait until the current
jiffie ends. If this condition is not met, then alloc_page() won't have
waited much if at all. In that case memalloc_retry_wait() waits about
200ms. This is the delay that most current loops uses.

linux/sched/mm.h needs to be included in some files now,
but linux/backing-dev.h does not.

Link: https://lkml.kernel.org/r/163754371968.13692.1277530886009912421@noble.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: invalidate META_MAPPING before IPU/DIO write

Encrypted pages during GC are read and cached in META_MAPPING.
However, due to cached pages in META_MAPPING, there is an issue where
newly written pages are lost by IPU or DIO writes.

Thread A - f2fs_gc() Thread B
/* phase 3 */
down_write(i_gc_rwsem)
ra_data_block() ---- (a)
up_write(i_gc_rwsem)
f2fs_direct_IO() :
- down_read(i_gc_rwsem)
- __blockdev_direct_io()
- get_data_block_dio_write()
- f2fs_dio_submit_bio() ---- (b)
- up_read(i_gc_rwsem)
/* phase 4 */
down_write(i_gc_rwsem)
move_data_block() ---- (c)
up_write(i_gc_rwsem)

(a) In phase 3 of f2fs_gc(), up-to-date page is read from storage and
cached in META_MAPPING.
(b) In thread B, writing new data by IPU or DIO write on same blkaddr as
read in (a). cached page in META_MAPPING become out-dated.
(c) In phase 4 of f2fs_gc(), out-dated page in META_MAPPING is copied to
new blkaddr. In conclusion, the newly written data in (b) is lost.

To address this issue, invalidating pages in META_MAPPING before IPU or
DIO write.

Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC")
Signed-off-by: Hyeong-Jun Kim <hj514.kim@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix overwrite may reduce compress ratio unproperly

when overwrite only first block of cluster, since cluster is not full, it
will call f2fs_write_raw_pages when f2fs_write_multi_pages, and cause the
whole cluster become uncompressed eventhough data can be compressed.
this may will make random write bench score reduce a lot.

root# dd if=/dev/zero of=./fio-test bs=1M count=1

root# sync

root# echo 3 > /proc/sys/vm/drop_caches

root# f2fs_io get_cblocks ./fio-test

root# dd if=/dev/zero of=./fio-test bs=4K count=1 oflag=direct conv=notrunc

w/o patch:
root# f2fs_io get_cblocks ./fio-test
189

w/ patch:
root# f2fs_io get_cblocks ./fio-test
192

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: multidevice: support direct IO

Commit 3c62be17d4f5 ("f2fs: support multiple devices") missed
to support direct IO for multiple device feature, this patch
adds to support the missing part of multidevice feature.

In addition, for multiple device image, we should be aware of
any issued direct write IO rather than just buffered write IO,
so that fsync and syncfs can issue a preflush command to the
device where direct write IO goes, to persist user data for
posix compliant.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: should put a page beyond EOF when preparing a write

The prepare_compress_overwrite() gets/locks a page to prepare a read, and calls
f2fs_read_multi_pages() which checks EOF first. If there's any page beyond EOF,
we unlock the page and set cc->rpages[i] = NULL, which we can't put the page
anymore. This makes page leak, so let's fix by putting that page.

Fixes: a949dc5f2c5c ("f2fs: compress: fix race condition of overwrite vs truncate")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()

In below path, it will return ENOENT if filesystem is shutdown:

- f2fs_map_blocks
- f2fs_get_dnode_of_data
- f2fs_get_node_page
- __get_node_page
- read_node_page
- is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN)
return -ENOENT
- force return value from ENOENT to 0

It should be fine for read case, since it indicates a hole condition,
and caller could use .m_next_pgofs to skip the hole and continue the
lookup.

However it may cause confusing for write case, since leaving a hole
there, and said nothing was wrong doesn't help.

There is at least one case from dax_iomap_actor() will complain that,
so fix this in prior to supporting dax in f2fs.

xfstest generic/388 reports below warning:

ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 485833 at fs/dax.c:1127 dax_iomap_actor+0x339/0x370
Call Trace:
iomap_apply+0x1c4/0x7b0
? dax_iomap_rw+0x1c0/0x1c0
dax_iomap_rw+0xad/0x1c0
? dax_iomap_rw+0x1c0/0x1c0
f2fs_file_write_iter+0x5ab/0x970 [f2fs]
do_iter_readv_writev+0x273/0x2e0
do_iter_write+0xab/0x1f0
vfs_iter_write+0x21/0x40
iter_file_splice_write+0x287/0x540
do_splice+0x37c/0xa60
__x64_sys_splice+0x15f/0x3a0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae

ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs:
------------[ cut here ]------------
RIP: 0010:dax_iomap_pte_fault.isra.0+0x72e/0x14a0
Call Trace:
dax_iomap_fault+0x44/0x70
f2fs_dax_huge_fault+0x155/0x400 [f2fs]
f2fs_dax_fault+0x18/0x30 [f2fs]
__do_fault+0x4e/0x120
do_fault+0x3cf/0x7a0
__handle_mm_fault+0xa8c/0xf20
? find_held_lock+0x39/0xd0
handle_mm_fault+0x1b6/0x480
do_user_addr_fault+0x320/0xcd0
? rcu_read_lock_sched_held+0x67/0xc0
exc_page_fault+0x77/0x3f0
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30

Fixes: 83a3bfdb5a8a ("f2fs: indicate shutdown f2fs to allow unmount successfully")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce periodic iostat io latency traces

Whenever we notice some sluggish issues on our machines, we are always
curious about how well all types of I/O in the f2fs filesystem are
handled. But, it's hard to get this kind of real data. First of all,
we need to reproduce the issue while turning on the profiling tool like
blktrace, but the issue doesn't happen again easily. Second, with the
intervention of any tools, the overall timing of the issue will be
slightly changed and it sometimes makes us hard to figure it out.

So, I added the feature printing out IO latency statistics tracepoint
events, which are minimal things to understand filesystem's I/O related
behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs
node on, we can get this statistics info in a periodic way and it
would cause the least overhead.

[samples]
f2fs_ckpt-254:1-507 [003] .... 2842.439683: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4],
wr_sync_data [164/16/3331], wr_sync_node [152/3/648],
wr_sync_meta [160/2/4243], wr_async_data [24/13/15],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

f2fs_ckpt-254:1-507 [002] .... 2845.450514: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1],
wr_sync_data [120/12/2285], wr_sync_node [88/5/428],
wr_sync_meta [52/6/2990], wr_async_data [4/1/3],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: separate out iostat feature

Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: do sanity check on cluster

This patch adds f2fs_sanity_check_cluster() to support doing
sanity check on cluster of compressed file, it will be triggered
from below two paths:

- __f2fs_cluster_blocks()
- f2fs_map_blocks(F2FS_GET_BLOCK_FIEMAP)

And it can detect below three kind of cluster insanity status.

C: COMPRESS_ADDR
N: NULL_ADDR or NEW_ADDR
V: valid blkaddr
*: any value

1. [*|C|*|*]
2. [C|*|C|*]
3. [C|N|N|V]

Signed-off-by: Chao Yu <chao@kernel.org>
[Nathan Chancellor: fix missing inline warning]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support fault injection for f2fs_kmem_cache_alloc()

This patch supports to inject fault into f2fs_kmem_cache_alloc().

Usage:
a) echo 32768 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=32768 <dev> <mountpoint>

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: avoid duplicate counting of valid blocks when read compressed file

Since cluster is basic unit of compression, one cluster is compressed or
not, so we can calculate valid blocks only for first page in cluster,
the other pages just skip.

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: extent cache: support unaligned extent

Compressed inode may suffer read performance issue due to it can not
use extent cache, so I propose to add this unaligned extent support
to improve it.

Currently, it only works in readonly format f2fs image.

Unaligned extent: in one compressed cluster, physical block number
will be less than logical block number, so we add an extra physical
block length in extent info in order to indicate such extent status.

The idea is if one whole cluster blocks are contiguous physically,
once its mapping info was readed at first time, we will cache an
unaligned (or aligned) extent info entry in extent cache, it expects
that the mapping info will be hitted when rereading cluster.

Merge policy:
- Aligned extents can be merged.
- Aligned extent and unaligned extent can not be merged.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: turn back remapped address in compressed page endio

Turned back the remmaped sector address to the address in the partition,
when ending io, for compress cache to work properly.

Fixes: 6ce19aff0b8c ("f2fs: compress: add compress_inode to cache
compressed blocks")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Hyeong Jun Kim <hj514.kim@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: change fiemap way in printing compression chunk

When we print out a discontinuous compression chunk, it shows like a
continuous chunk now. To show it more correctly, I've changed the way of
printing fiemap info like below. Plus, eliminated NEW_ADDR(-1) in fiemap
info, since it is not in fiemap user api manual.

Let's assume 16KB compression cluster.

<before>
Logical Physical Length Flags
0: 0000000000000000 00000002c091f000 0000000000004000 1008
1: 0000000000004000 00000002c0920000 0000000000004000 1008
...
9: 0000000000034000 0000000f8c623000 0000000000004000 1008
10: 0000000000038000 000000101a6eb000 0000000000004000 1008

<after>
0: 0000000000000000 00000002c091f000 0000000000004000 1008
1: 0000000000004000 00000002c0920000 0000000000004000 1008
...
9: 0000000000034000 0000000f8c623000 0000000000001000 1008
10: 0000000000035000 000000101a6ea000 0000000000003000 1008
11: 0000000000038000 000000101a6eb000 0000000000002000 1008
12: 000000000003a000 00000002c3544000 0000000000002000 1008

Flags
0x1000 => FIEMAP_EXTENT_MERGED
0x0008 => FIEMAP_EXTENT_ENCODED

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Tested-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: remove unneeded read when rewrite whole cluster

when we overwrite the whole page in cluster, we don't need read original
data before write, because after write_end(), writepages() can help to
load left data in that cluster.

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove allow_outplace_dio()

We can just check f2fs_lfs_mode() directly. The block_unaligned_IO()
check is redundant because in LFS mode, f2fs doesn't do direct I/O
writes that aren't block-aligned (due to f2fs_force_buffered_io()
returning true in this case, triggering the fallback to buffered I/O).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: make f2fs_write_failed() take struct inode

Make f2fs_write_failed() take a 'struct inode' directly rather than a
'struct address_space', as this simplifies it slightly.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: let's keep writing IOs on SBI_NEED_FSCK

SBI_NEED_FSCK is an indicator that fsck.f2fs needs to be triggered, so it
is not fully critical to stop any IO writes. So, let's allow to write data
instead of reporting EIO forever given SBI_NEED_FSCK, but do keep OPU.

Fixes: 955772787667 ("f2fs: drop inplace IO if fs status is abnormal")
Cc: <stable@kernel.org> # v5.13+
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Convert to using invalidate_lock

Use invalidate_lock instead of f2fs' private i_mmap_sem. The intended
purpose is exactly the same. By this conversion we fix a long standing
race between hole punching and read(2) / readahead(2) paths that can
lead to stale page cache contents.

CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: Chao Yu <yuchao0@huawei.com>
CC: linux-f2fs-devel@lists.sourceforge.net
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>

f2fs: initialize page->private when using for our internal use

We need to guarantee it's initially zero. Otherwise, it'll hurt entire flag
operations.

Fixes: b763f3bedc2d ("f2fs: restructure f2fs page.private layout")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: swap: support migrating swapfile in aligned write mode

This patch supports to migrate swapfile in aligned write mode during
swapon in order to keep swapfile being aligned to section as much as
possible, then pinned swapfile will locates fully filled section which
may not affected by GC.

However, for the case that swapfile's size is not aligned to section
size, it will still leave last extent in file's tail as unaligned due
to its size is smaller than section size, like case #2.

case #1
xfs_io -f /mnt/f2fs/file -c "pwrite 0 4M" -c "fsync"

Before swapon:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..3047]: 1123352..1126399 3048 0x1000
1: [3048..7143]: 237568..241663 4096 0x1000
2: [7144..8191]: 245760..246807 1048 0x1001
After swapon:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..8191]: 249856..258047 8192 0x1001
Kmsg:
F2FS-fs (zram0): Swapfile (2) is not align to section:
1) creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate(2097152 * n)

case #2
xfs_io -f /mnt/f2fs/file -c "pwrite 0 3M" -c "fsync"

Before swapon:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..3047]: 246808..249855 3048 0x1000
1: [3048..6143]: 237568..240663 3096 0x1001
After swapon:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..4095]: 258048..262143 4096 0x1000
1: [4096..6143]: 238616..240663 2048 0x1001
Kmsg:
F2FS-fs (zram0): Swapfile: last extent is not aligned to section
F2FS-fs (zram0): Swapfile (2) is not align to section:
1) creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate(2097152 * n)

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: swap: remove dead codes

After commit af4b6b8edf6a ("f2fs: introduce check_swap_activate_fast()"),
we will never run into original logic of check_swap_activate() before
f2fs supports non 4k-sized page, so let's delete those dead codes.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: add compress_inode to cache compressed blocks

Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: logging neatening

Update the logging uses that have unnecessary newlines as the f2fs_printk
function and so its f2fs_<level> macro callers already adds one.

This allows searching single line logging entries with an easier grep and
also avoids unnecessary blank lines in the logging.

Miscellanea:

o Coalesce formats
o Align to open parenthesis

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Prevent swap file in LFS mode

The kernel writes to swap files on f2fs directly without the assistance
of the filesystem. This direct write by kernel can be non-sequential
even when the f2fs is in LFS mode. Such non-sequential write conflicts
with the LFS semantics. Especially when f2fs is set up on zoned block
devices, the non-sequential write causes unaligned write command errors.

To avoid the non-sequential writes to swap files, prevent swap file
activation when the filesystem is in LFS mode.

Fixes: 4969c06a0d83 ("f2fs: support swap file w/ DIO")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.10+
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: restructure f2fs page.private layout

Restruct f2fs page private layout for below reasons:

There are some cases that f2fs wants to set a flag in a page to
indicate a specified status of page:
a) page is in transaction list for atomic write
b) page contains dummy data for aligned write
c) page is migrating for GC
d) page contains inline data for inline inode flush
e) page belongs to merkle tree, and is verified for fsverity
f) page is dirty and has filesystem/inode reference count for writeback
g) page is temporary and has decompress io context reference for compression

There are existed places in page structure we can use to store
f2fs private status/data:
- page.flags: PG_checked, PG_private
- page.private

However it was a mess when we using them, which may cause potential
confliction:
page.private PG_private PG_checked page._refcount (+1 at most)
a) -1 set +1
b) -2 set
c), d), e) set
f) 0 set +1
g) pointer set

The other problem is page.flags has no free slot, if we can avoid set
zero to page.private and set PG_private flag, then we use non-zero value
to indicate PG_private status, so that we may have chance to reclaim
PG_private slot for other usage. [1]

The other concern is f2fs has bad scalability in aspect of indicating
more page status.

So in this patch, let's restructure f2fs' page.private as below to
solve above issues:

Layout A: lowest bit should be 1
| bit0 = 1 | bit1 | bit2 | ... | bit MAX | private data .... |
bit 0 PAGE_PRIVATE_NOT_POINTER
bit 1 PAGE_PRIVATE_ATOMIC_WRITE
bit 2 PAGE_PRIVATE_DUMMY_WRITE
bit 3 PAGE_PRIVATE_ONGOING_MIGRATION
bit 4 PAGE_PRIVATE_INLINE_INODE
bit 5 PAGE_PRIVATE_REF_RESOURCE
bit 6- f2fs private data

Layout B: lowest bit should be 0
page.private is a wrapped pointer.

After the change:
page.private PG_private PG_checked page._refcount (+1 at most)
a) 11 set +1
b) 101 set +1
c) 1001 set +1
d) 10001 set +1
e) set
f) 100001 set +1
g) pointer set +1

[1] https://lore.kernel.org/linux-f2fs-devel/20210422154705.GO3596236@casper.infradead.org/T/#u

Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: return EINVAL for hole cases in swap file

This tries to fix xfstests/generic/495.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid swapon failure by giving a warning first

The final solution can be migrating blocks to form a section-aligned file
internally. Meanwhile, let's ask users to do that when preparing the swap
file initially like:
1) create()
2) ioctl(F2FS_IOC_SET_PIN_FILE)
3) fallocate()

Reported-by: kernel test robot <oliver.sang@intel.com>
Fixes: 36e4d95891ed ("f2fs: check if swapfile is section-alligned")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to assign cc.cluster_idx correctly

In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(),
cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks()
may check wrong cluster metadata, fix it.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up build warnings

This patch combined the below three clean-up patches.

- modify open brace '{' following function definitions
- ERROR: spaces required around that ':'
- ERROR: spaces required before the open parenthesis '('
- ERROR: spaces prohibited before that ','
- Made suggested modifications from checkpatch in reference to WARNING:
Missing a blank line after declarations

Signed-off-by: Yi Zhuang <zhuangyi1@huawei.com>
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to use per-inode maxbytes in f2fs_fiemap

F2FS inode may have different max size,
so change to use per-inode maxbytes.

Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: check if swapfile is section-alligned

If the swapfile isn't created by pin and fallocate, it can't be
guaranteed section-aligned, so it may be selected by f2fs gc. When
gc_pin_file_threshold is reached, the address of swapfile may change,
but won't be synchronized to swap_extent, so swap will write to wrong
address, which will cause data corruption.

Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Guo Weichao <guoweichao@oppo.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix last_lblock check in check_swap_activate_fast

Because page_no < sis->max guarantees that the while loop break out
normally, the wrong check contidion here doesn't cause a problem.

Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Guo Weichao <guoweichao@oppo.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove unnecessary IS_SWAPFILE check

Now swapfile in f2fs directly submit IO to blockdev according to
swapfile extents reported by f2fs when swapon, therefore there is
no need to check IS_SWAPFILE when exec filesystem operation.

Signed-off-by: Huang Jianan <huangjianan@oppo.com>
Signed-off-by: Guo Weichao <guoweichao@oppo.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

block: rename BIO_MAX_PAGES to BIO_MAX_VECS

Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Add bio_max_segs

It's often inconvenient to use BIO_MAX_PAGES due to min() requiring the
sign to be the same. Introduce bio_max_segs() and change BIO_MAX_PAGES to
be unsigned to make it easier for the users.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: fix a wrong condition in __submit_bio

We should use !F2FS_IO_ALIGNED() to check and submit_io directly.

Fixes: 8223ecc456d0 ("f2fs: fix to add missing F2FS_IO_ALIGNED() condition")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Dehe Gu <gudehe@huawei.com>
Signed-off-by: Ge Qiu <qiuge@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: deprecate f2fs_trace_io

This patch deprecates f2fs_trace_io, since f2fs uses page->private more broadly,
resulting in more buggy cases.

Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Remove readahead collision detection

With the new ->readahead operation, locked pages are added to the page
cache, preventing two threads from racing with each other to read the
same chunk of file, so this is dead code.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to use per-inode maxbytes

F2FS inode may have different max size, e.g. compressed file have
less blkaddr entries in all its direct-node blocks, result in being
with less max filesize. So change to use per-inode maxbytes.

Suggested-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix potential deadlock

generic/269 reports a hangtask issue, the root cause is ABBA deadlock
described as below:

Thread A Thread B
- down_write(&sbi->gc_lock) -- A
- f2fs_write_data_pages
- lock all pages in cluster -- B
- f2fs_write_multi_pages
- f2fs_write_raw_pages
- f2fs_write_single_data_page
- f2fs_balance_fs
- down_write(&sbi->gc_lock) -- A
- f2fs_gc
- do_garbage_collect
- ra_data_block
- pagecache_get_page -- B

To fix this, it needs to avoid calling f2fs_balance_fs() if there is
still cluster pages been locked in context of cluster writeback, so
instead, let's call f2fs_balance_fs() in the end of
f2fs_write_raw_pages() when all cluster pages were unlocked.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up post-read processing

Rework the post-read processing logic to be much easier to understand.

At least one bug is fixed by this: if an I/O error occurred when reading
from disk, decryption and verity would be performed on the uninitialized
data, causing misleading messages in the kernel log.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to tag FIEMAP_EXTENT_MERGED in f2fs_fiemap()

f2fs does not natively support extents in metadata, 'extent' in f2fs
is used as a virtual concept, so in f2fs_fiemap() interface, it needs
to tag FIEMAP_EXTENT_MERGED flag to indicated the extent status is a
result of merging.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: relocate f2fs_precache_extents()

Relocate f2fs_precache_extents() in prior to check_swap_activate(),
then extent cache can be enabled before its use.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove FAULT_ALLOC_BIO

Sleeping bio allocations do not fail, which means that injecting an error
into sleeping bio allocations is a little silly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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>

f2fs: use blkdev_issue_flush in __submit_flush_wait

Use the blkdev_issue_flush helper instead of duplicating it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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>

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>

f2fs: fix race of pending_pages in decompression

I found out f2fs_free_dic() is invoked in a wrong timing, but
f2fs_verify_bio() still needed the dic info and it triggered the
below kernel panic. It has been caused by the race condition of
pending_pages value between decompression and verity logic, when
the same compression cluster had been split in different bios.
By split bios, f2fs_verify_bio() ended up with decreasing
pending_pages value before it is reset to nr_cpages by
f2fs_decompress_pages() and caused the kernel panic.

[ 4416.564763] Unable to handle kernel NULL pointer dereference
at virtual address 0000000000000000
...
[ 4416.896016] Workqueue: fsverity_read_queue f2fs_verity_work
[ 4416.908515] pc : fsverity_verify_page+0x20/0x78
[ 4416.913721] lr : f2fs_verify_bio+0x11c/0x29c
[ 4416.913722] sp : ffffffc019533cd0
[ 4416.913723] x29: ffffffc019533cd0 x28: 0000000000000402
[ 4416.913724] x27: 0000000000000001 x26: 0000000000000100
[ 4416.913726] x25: 0000000000000001 x24: 0000000000000004
[ 4416.913727] x23: 0000000000001000 x22: 0000000000000000
[ 4416.913728] x21: 0000000000000000 x20: ffffffff2076f9c0
[ 4416.913729] x19: ffffffff2076f9c0 x18: ffffff8a32380c30
[ 4416.913731] x17: ffffffc01f966d97 x16: 0000000000000298
[ 4416.913732] x15: 0000000000000000 x14: 0000000000000000
[ 4416.913733] x13: f074faec89ffffff x12: 0000000000000000
[ 4416.913734] x11: 0000000000001000 x10: 0000000000001000
[ 4416.929176] x9 : ffffffff20d1f5c7 x8 : 0000000000000000
[ 4416.929178] x7 : 626d7464ff286b6b x6 : ffffffc019533ade
[ 4416.929179] x5 : 000000008049000e x4 : ffffffff2793e9e0
[ 4416.929180] x3 : 000000008049000e x2 : ffffff89ecfa74d0
[ 4416.929181] x1 : 0000000000000c40 x0 : ffffffff2076f9c0
[ 4416.929184] Call trace:
[ 4416.929187] fsverity_verify_page+0x20/0x78
[ 4416.929189] f2fs_verify_bio+0x11c/0x29c
[ 4416.929192] f2fs_verity_work+0x58/0x84
[ 4417.050667] process_one_work+0x270/0x47c
[ 4417.055354] worker_thread+0x27c/0x4d8
[ 4417.059784] kthread+0x13c/0x320
[ 4417.063693] ret_from_fork+0x10/0x18

Chao pointed this can happen by the below race condition.

Thread A f2fs_post_read_wq fsverity_wq
- f2fs_read_multi_pages()
- f2fs_alloc_dic
- dic->pending_pages = 2
- submit_bio()
- submit_bio()
- f2fs_post_read_work() handle first bio
- f2fs_decompress_work()
- __read_end_io()
- f2fs_decompress_pages()
- dic->pending_pages--
- enqueue f2fs_verity_work()
- f2fs_verity_work() handle first bio
- f2fs_verify_bio()
- dic->pending_pages--
- f2fs_post_read_work() handle second bio
- f2fs_decompress_work()
- enqueue f2fs_verity_work()
- f2fs_verify_pages()
- f2fs_free_dic()

- f2fs_verity_work() handle second bio
- f2fs_verfy_bio()
- use-after-free on dic

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size

This patch adds max_io_bytes to limit bio size when f2fs tries to merge
consecutive IOs. This can give a testing point to split out bios and check
end_io handles those bios correctly. This is used to capture a recent bug
on the decompression and fsverity flow.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add compress_mode mount option

We will add a new "compress_mode" mount option to control file
compression mode. This supports "fs" and "user". In "fs" mode (default),
f2fs does automatic compression on the compression enabled files.
In "user" mode, f2fs disables the automaic compression and gives the
user discretion of choosing the target file and the timing. It means
the user can do manual compression/decompression on the compression
enabled files using ioctls.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove buffer_head which has 32bits limit

This patch removes buffer_head dependency when getting block addresses.
Light reported there's a 32bit issue in f2fs_fiemap where map_bh.b_size is
32bits while len is 64bits given by user. This will give wrong length to
f2fs_map_block.

Reported-by: Light Hsieh <Light.Hsieh@mediatek.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix wrong block count instead of bytes

We should convert cur_lblock, a block count, to bytes for len.

Fixes: af4b6b8edf6a ("f2fs: introduce check_swap_activate_fast()")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use new conversion functions between blks and bytes

This patch cleans up blks and bytes conversions.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: rename logical_to_blk and blk_to_logical

This patch renames two functions like below having u64.
- logical_to_blk to bytes_to_blks
- blk_to_logical to blks_to_bytes

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce check_swap_activate_fast()

check_swap_activate() will lookup block mapping via bmap() one by one, so
its performance is very bad, this patch introduces check_swap_activate_fast()
to use f2fs_fiemap() to boost this process, since f2fs_fiemap() will lookup
block mappings in batch, therefore, it can improve swapon()'s performance
significantly.

Note that this enhancement only works when page size is equal to f2fs' block
size.

Testcase: (backend device: zram)
- touch file
- pin & fallocate file to 8GB
- mkswap file
- swapon file

Before:
real 0m2.999s
user 0m0.000s
sys 0m2.980s

After:
real 0m0.081s
user 0m0.000s
sys 0m0.064s

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix slab leak of rpages pointer

This fixes the below mem leak.

[ 130.157600] =============================================================================
[ 130.159662] BUG f2fs_page_array_entry-252:16 (Tainted: G W O ): Objects remaining in f2fs_page_array_entry-252:16 on __kmem_cache_shutdown()
[ 130.162742] -----------------------------------------------------------------------------
[ 130.162742]
[ 130.164979] Disabling lock debugging due to kernel taint
[ 130.166188] INFO: Slab 0x000000009f5a52d2 objects=22 used=4 fp=0x00000000ba72c3e9 flags=0xfffffc0010200
[ 130.168269] CPU: 7 PID: 3560 Comm: umount Tainted: G B W O 5.9.0-rc4+ #35
[ 130.170019] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014
[ 130.171941] Call Trace:
[ 130.172528] dump_stack+0x74/0x9a
[ 130.173298] slab_err+0xb7/0xdc
[ 130.174044] ? kernel_poison_pages+0xc0/0xc0
[ 130.175065] ? on_each_cpu_cond_mask+0x48/0x90
[ 130.176096] __kmem_cache_shutdown.cold+0x34/0x141
[ 130.177190] kmem_cache_destroy+0x59/0x100
[ 130.178223] f2fs_destroy_page_array_cache+0x15/0x20 [f2fs]
[ 130.179527] f2fs_put_super+0x1bc/0x380 [f2fs]
[ 130.180538] generic_shutdown_super+0x72/0x110
[ 130.181547] kill_block_super+0x27/0x50
[ 130.182438] kill_f2fs_super+0x76/0xe0 [f2fs]
[ 130.183448] deactivate_locked_super+0x3b/0x80
[ 130.184456] deactivate_super+0x3e/0x50
[ 130.185363] cleanup_mnt+0x109/0x160
[ 130.186179] __cleanup_mnt+0x12/0x20
[ 130.187003] task_work_run+0x70/0xb0
[ 130.187841] exit_to_user_mode_prepare+0x18f/0x1b0
[ 130.188917] syscall_exit_to_user_mode+0x31/0x170
[ 130.189989] do_syscall_64+0x45/0x90
[ 130.190828] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 130.191986] RIP: 0033:0x7faf868ea2eb
[ 130.192815] Code: 7b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 90 f3 0f 1e fa 31 f6 e9 05 00 00 00 0f 1f 44 00 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 7b 0c 00 f7 d8 64 89 01
[ 130.196872] RSP: 002b:00007fffb7edb478 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 130.198494] RAX: 0000000000000000 RBX: 00007faf86a18204 RCX: 00007faf868ea2eb
[ 130.201021] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055971df71c50
[ 130.203415] RBP: 000055971df71a40 R08: 0000000000000000 R09: 00007fffb7eda1f0
[ 130.205772] R10: 00007faf86a04339 R11: 0000000000000246 R12: 000055971df71c50
[ 130.208150] R13: 0000000000000000 R14: 000055971df71b38 R15: 0000000000000000
[ 130.210515] INFO: Object 0x00000000a980843a @offset=744
[ 130.212476] INFO: Allocated in page_array_alloc+0x3d/0xe0 [f2fs] age=1572 cpu=0 pid=3297
[ 130.215030] __slab_alloc+0x20/0x40
[ 130.216566] kmem_cache_alloc+0x2a0/0x2e0
[ 130.218217] page_array_alloc+0x3d/0xe0 [f2fs]
[ 130.219940] f2fs_init_compress_ctx+0x1f/0x40 [f2fs]
[ 130.221736] f2fs_write_cache_pages+0x3db/0x860 [f2fs]
[ 130.223591] f2fs_write_data_pages+0x2c9/0x300 [f2fs]
[ 130.225414] do_writepages+0x43/0xd0
[ 130.226907] __filemap_fdatawrite_range+0xd5/0x110
[ 130.228632] filemap_write_and_wait_range+0x48/0xb0
[ 130.230336] __generic_file_write_iter+0x18a/0x1d0
[ 130.232035] f2fs_file_write_iter+0x226/0x550 [f2fs]
[ 130.233737] new_sync_write+0x113/0x1a0
[ 130.235204] vfs_write+0x1a6/0x200
[ 130.236579] ksys_write+0x67/0xe0
[ 130.237898] __x64_sys_write+0x1a/0x20
[ 130.239309] do_syscall_64+0x38/0x90

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up kvfree

After commit 0b6d4ca04a86 ("f2fs: don't return vmalloc() memory from
f2fs_kmalloc()"), f2fs_k{m,z}alloc() will not return vmalloc()'ed
memory, so clean up to use kfree() instead of kvfree() to free
vmalloc()'ed memory.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: change return value of f2fs_disable_compressed_file to bool

The returned integer is not required anywhere. So we need to change
the return value to bool type.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add block address limit check to compressed file

Need to add block address range check to compressed file case and
avoid calling get_data_block_bmap() for compressed file.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: correct statistic of APP_DIRECT_IO/APP_DIRECT_READ_IO

Miss to update APP_DIRECT_IO/APP_DIRECT_READ_IO when receiving async DIO.
For example: fio -filename=/data/test.0 -bs=1m -ioengine=libaio -direct=1
-name=fill -size=10m -numjobs=1 -iodepth=32 -rw=write

Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support age threshold based garbage collection

There are several issues in current background GC algorithm:
- valid blocks is one of key factors during cost overhead calculation,
so if segment has less valid block, however even its age is young or
it locates hot segment, CB algorithm will still choose the segment as
victim, it's not appropriate.
- GCed data/node will go to existing logs, no matter in-there datas'
update frequency is the same or not, it may mix hot and cold data
again.
- GC alloctor mainly use LFS type segment, it will cost free segment
more quickly.

This patch introduces a new algorithm named age threshold based
garbage collection to solve above issues, there are three steps
mainly:

1. select a source victim:
- set an age threshold, and select candidates beased threshold:
e.g.
0 means youngest, 100 means oldest, if we set age threshold to 80
then select dirty segments which has age in range of [80, 100] as
candiddates;
- set candidate_ratio threshold, and select candidates based the
ratio, so that we can shrink candidates to those oldest segments;
- select target segment with fewest valid blocks in order to
migrate blocks with minimum cost;

2. select a target victim:
- select candidates beased age threshold;
- set candidate_radius threshold, search candidates whose age is
around source victims, searching radius should less than the
radius threshold.
- select target segment with most valid blocks in order to avoid
migrating current target segment.

3. merge valid blocks from source victim into target victim with
SSR alloctor.

Test steps:
- create 160 dirty segments:
* half of them have 128 valid blocks per segment
* left of them have 384 valid blocks per segment
- run background GC

Benefit: GC count and block movement count both decrease obviously:

- Before:
- Valid: 86
- Dirty: 1
- Prefree: 11
- Free: 6001 (6001)

GC calls: 162 (BG: 220)
- data segments : 160 (160)
- node segments : 2 (2)
Try to move 41454 blocks (BG: 41454)
- data blocks : 40960 (40960)
- node blocks : 494 (494)

IPU: 0 blocks
SSR: 0 blocks in 0 segments
LFS: 41364 blocks in 81 segments

- After:

- Valid: 87
- Dirty: 0
- Prefree: 4
- Free: 6008 (6008)

GC calls: 75 (BG: 76)
- data segments : 74 (74)
- node segments : 1 (1)
Try to move 12813 blocks (BG: 12813)
- data blocks : 12544 (12544)
- node blocks : 269 (269)

IPU: 0 blocks
SSR: 12032 blocks in 77 segments
LFS: 855 blocks in 2 segments

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix a bug along with pinfile in-mem segment & clean up]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: use more readable atomic_t type for {cic,dic}.ref

refcount_t type variable should never be less than one, so it's a
little bit hard to understand when we use it to indicate pending
compressed page count, let's change to use atomic_t for better
readability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: inherit mtime of original block during GC

Don't let f2fs inner GC ruins original aging degree of segment.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove duplicated type casting

Since DUMMY_WRITTEN_PAGE and ATOMIC_WRITTEN_PAGE have already been
converted as unsigned long type, we don't need do type casting again.

Signed-off-by: Xiaojun Wang <wangxiaojun11@huawei.com>
Reported-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Return EOF on unaligned end of file DIO read

Reading past end of file returns EOF for aligned reads but -EINVAL for
unaligned reads on f2fs. While documentation is not strict about this
corner case, most filesystem returns EOF on this case, like iomap
filesystems. This patch consolidates the behavior for f2fs, by making
it return EOF(0).

it can be verified by a read loop on a file that does a partial read
before EOF (A file that doesn't end at an aligned address). The
following code fails on an unaligned file on f2fs, but not on
btrfs, ext4, and xfs.

while (done < total) {
ssize_t delta = pread(fd, buf + done, total - done, off + done);
if (!delta)
break;
...
}

It is arguable whether filesystems should actually return EOF or
-EINVAL, but since iomap filesystems support it, and so does the
original DIO code, it seems reasonable to consolidate on that.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: add sanity check during compressed cluster read

In f2fs_read_multi_pages(), we don't have to check cluster's type
again, since overwrite or partial truncation need page lock in
cluster which has already been held by reader, so cluster's type
is stable, let's change check condition to sanity check.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: fix to update isize when overwriting compressed file

We missed to update isize of compressed file in write_end() with
below case:

cluster size is 16KB

- write 14KB data from offset 0
- overwrite 16KB data from offset 0

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: space related cleanup

Just for code style, no logic change
1. delete useless space
2. change spaces into tab

Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Eliminate usage of uninitialized_var() macro

This is an effort to eliminate the uninitialized_var() macro[1].

The use of this macro is the wrong solution because it forces off ANY
analysis by the compiler for a given variable. It even masks "unused
variable" warnings.

Quoted from Linus[2]:

"It's a horrible thing to use, in that it adds extra cruft to the
source code, and then shuts up a compiler warning (even the _reliable_
warnings from gcc)."

Fix it by remove this variable since it is not needed at all.

[1] https://github.com/KSPP/linux/issues/81
[2] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Suggested-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200615085132.166470-1-yanaijie@huawei.com
Signed-off-by: Kees Cook <keescook@chromium.org>

f2fs: add inline encryption support

Wire up f2fs to support inline encryption via the helper functions which
fs/crypto/ now provides. This includes:

- Adding a mount option 'inlinecrypt' which enables inline encryption
on encrypted files where it can be used.

- Setting the bio_crypt_ctx on bios that will be submitted to an
inline-encrypted file.

- Not adding logically discontiguous data to bios that will be submitted
to an inline-encrypted file.

- Not doing filesystem-layer crypto on inline-encrypted files.

This patch includes a fix for a race during IPU by
Sahitya Tummala <stummala@codeaurora.org>

Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200702015607.1215430-4-satyat@google.com
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

f2fs: avoid readahead race condition

If two readahead threads having same offset enter in readpages, every read
IOs are split and issued to the disk which giving lower bandwidth.

This patch tries to avoid redundant readahead calls.

Fixes one build error reported by Randy.
Fix build error when F2FS_FS_COMPRESSION is not set/enabled.
This label is needed in either case.

../fs/f2fs/data.c: In function ‘f2fs_mpage_readpages’:
../fs/f2fs/data.c:2327:5: error: label ‘next_page’ used but not defined
goto next_page;

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add parameter op_flag in f2fs_submit_page_read()

The parameter op_flag is not used in f2fs_get_read_data_page(),
but it is used in f2fs_grab_read_bio(). Obviously, op_flag is
not passed to f2fs_grab_read_bio() successfully. We need to add
parameter in f2fs_submit_page_read() to pass it.

The case:
- gc_data_segment
- f2fs_get_read_data_page(.., op_flag = REQ_RAHEAD,..)
- f2fs_submit_page_read
- f2fs_grab_read_bio(.., op_flag = 0, ..)

Signed-off-by: Jia Yang <jiayang5@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support to trace f2fs_fiemap()

to show f2fs_fiemap()'s result as below:

f2fs_fiemap: dev = (251,0), ino = 7, lblock:0, pblock:1625292800, len:2097152, flags:0, ret:0

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support to trace f2fs_bmap()

to show f2fs_bmap()'s result as below:

f2fs_bmap: dev = (251,0), ino = 7, lblock:0, pblock:396800

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix wrong return value of f2fs_bmap_compress()

If compression is disable, we should return zero rather than -EOPNOTSUPP
to indicate f2fs_bmap() is not supported.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up parameter of f2fs_allocate_data_block()

Use validation of @fio to inidcate whether caller want to serialize IOs
in io.io_list or not, then @add_list will be redundant, remove it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: shrink node_write lock coverage

- to avoid race between checkpoint and quota file writeback, it
just needs to hold read lock of node_write in writeback path.
- node_write lock has covered all LFS data write paths, it's not
necessary, we only need to hold node_write lock at write path of
quota file.

This refactors commit ca7f76e68074 ("f2fs: fix wrong discard space").

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add prefix for exported symbols

to avoid polluting global symbol namespace.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: attach IO flags to the missing cases

This adds more IOs to attach flags.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add node_io_flag for bio flags likewise data_io_flag

This patch adds another way to attach bio flags to node writes.

Description: Give a way to attach REQ_META|FUA to node writes
given temperature-based bits. Now the bits indicate:
* REQ_META | REQ_FUA |
* 5 | 4 | 3 | 2 | 1 | 0 |
* Cold | Warm | Hot | Cold | Warm | Hot |

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix retry logic in f2fs_write_cache_pages()

In case a compressed file is getting overwritten, the current retry
logic doesn't include the current page to be retried now as it sets
the new start index as 0 and new end index as writeback_index - 1.
This causes the corresponding cluster to be uncompressed and written
as normal pages without compression. Fix this by allowing writeback to
be retried for the current page as well (in case of compressed page
getting retried due to index mismatch with cluster index). So that
this cluster can be written compressed in case of overwrite.

Also, align f2fs_write_cache_pages() according to the change -
<64081362e8ff>("mm/page-writeback.c: fix range_cyclic writeback vs
writepages deadlock").

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs: handle FIEMAP_FLAG_SYNC in fiemap_prep

By moving FIEMAP_FLAG_SYNC handling to fiemap_prep we ensure it is
handled once instead of duplicated, but can still be done under fs locks,
like xfs/iomap intended with its duplicate handling. Also make sure the
error value of filemap_write_and_wait is propagated to user space.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-8-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs: move fiemap range validation into the file systems instances

Replace fiemap_check_flags with a fiemap_prep helper that also takes the
inode and mapped range, and performs the sanity check and truncation
previously done in fiemap_check_range. This way the validation is inside
the file system itself and thus properly works for the stacked overlayfs
case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-7-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs: move the fiemap definitions out of fs.h

No need to pull the fiemap definitions into almost every file in the
kernel build.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-5-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

f2fs: pass the inode to f2fs_mpage_readpages

This function now only uses the mapping argument to look up the inode, and
both callers already have the inode, so just pass the inode instead of the
mapping.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-24-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: convert from readpages to readahead

Use the new readahead operation in f2fs

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-23-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: add page_cache_readahead_unbounded

ext4 and f2fs have duplicated the guts of the readahead code so they can
read past i_size. Instead, separate out the guts of the readahead code
so they can call it directly.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-14-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: add compressed/gc data read IO stat

in order to account data read IOs more accurately.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix potential use-after-free issue

In error path of f2fs_read_multi_pages(), it should let last referrer
release decompress io context memory, otherwise, other referrer will
cause use-after-free issue.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: don't handle non-compressed data in workqueue

If bio has no compressed data, we don't need to handle end_io work in
workqueue, instead, it should just let interrupter handle it directly
to speed up IO response.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce f2fs_bmap_compress()

to support bmap() on compressed inode: if queried block locates in
non-compressed cluster, return its physical block address.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support fiemap on compressed inode

Map normal/compressed cluster of compressed inode correctly, and give
the right fiemap flag FIEMAP_EXTENT_ENCODED on mapped compressed extent.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix quota_sync failure due to f2fs_lock_op

f2fs_quota_sync() uses f2fs_lock_op() before flushing dirty pages, but
f2fs_write_data_page() returns EAGAIN.
Likewise dentry blocks, we can just bypass getting the lock, since quota
blocks are also maintained by checkpoint.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support read iostat

Adds to support accounting read IOs from userspace/kernel.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce sysfs/data_io_flag to attach REQ_META/FUA

This patch introduces a way to attach REQ_META/FUA explicitly
to all the data writes given temperature.

-> attach REQ_FUA to Hot Data writes

-> attach REQ_FUA to Hot|Warm Data writes

-> attach REQ_FUA to Hot|Warm|Cold Data writes

-> attach REQ_FUA to Hot|Warm|Cold Data writes as well as
REQ_META to Hot Data writes

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to use f2fs_readpage_limit() in f2fs_read_multi_pages()

Multipage read flow should consider fsverity, so it needs to use
f2fs_readpage_limit() instead of i_size_read() to check EOF condition.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to avoid double unlock

On image that has verity and compression feature, if compressed pages
and non-compressed pages are mixed in one bio, we may double unlock
non-compressed page in below flow:

- f2fs_post_read_work
- f2fs_decompress_work
- f2fs_decompress_bio
- __read_end_io
- unlock_page
- fsverity_enqueue_verify_work
- f2fs_verity_work
- f2fs_verify_bio
- unlock_page

So it should skip handling non-compressed page in f2fs_decompress_work()
if verity is on.

Besides, add missing dec_page_count() in f2fs_verify_bio().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix NULL pointer dereference in f2fs_verity_work()

If both compression and fsverity feature is on, generic/572 will
report below NULL pointer dereference bug.

BUG: kernel NULL pointer dereference, address: 0000000000000018
RIP: 0010:f2fs_verity_work+0x60/0x90 [f2fs]
#PF: supervisor read access in kernel mode
Workqueue: fsverity_read_queue f2fs_verity_work [f2fs]
RIP: 0010:f2fs_verity_work+0x60/0x90 [f2fs]
Call Trace:
process_one_work+0x16c/0x3f0
worker_thread+0x4c/0x440
? rescuer_thread+0x350/0x350
kthread+0xf8/0x130
? kthread_unpark+0x70/0x70
ret_from_fork+0x35/0x40

There are two issue in f2fs_verity_work():
- it needs to traverse and verify all pages in bio.
- if pages in bio belong to non-compressed cluster, accessing
decompress IO context stored in page private will cause NULL
pointer dereference.

Fix them.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to avoid potential deadlock

We should always check F2FS_I(inode)->cp_task condition in prior to other
conditions in __should_serialize_io() to avoid deadloop described in
commit 040d2bb318d1 ("f2fs: fix to avoid deadloop if data_flush is on"),
however we break this rule when we support compression, fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: delete DIO read lock

This lock can be a contention with multi 4k random read IO with single inode.

example) fio --output=test --name=test --numjobs=60 --filename=/media/samsung960pro/file_test --rw=randread --bs=4k
--direct=1 --time_based --runtime=7 --ioengine=libaio --iodepth=256 --group_reporting --size=10G

With this commit, it remove that possible lock contention.

Signed-off-by: Dongjoo Seo <commisori28@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid __GFP_NOFAIL in f2fs_bio_alloc

__f2fs_bio_alloc() won't fail due to memory pool backend, remove unneeded
__GFP_NOFAIL flag in __f2fs_bio_alloc().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to avoid triggering IO in write path

If we are in write IO path, we need to avoid using GFP_KERNEL.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add prefix for f2fs slab cache name

In order to avoid polluting global slab cache namespace.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce DEFAULT_IO_TIMEOUT

As Geert Uytterhoeven reported:

for parameter HZ/50 in congestion_wait(BLK_RW_ASYNC, HZ/50);

On some platforms, HZ can be less than 50, then unexpected 0 timeout
jiffies will be set in congestion_wait().

This patch introduces a macro DEFAULT_IO_TIMEOUT to wrap a determinate
value with msecs_to_jiffies(20) to instead HZ/50 to avoid such issue.

Quoted from Geert Uytterhoeven:

"A timeout of HZ means 1 second.
HZ/50 means 20 ms, but has the risk of being zero, if HZ < 50.

If you want to use a timeout of 20 ms, you best use msecs_to_jiffies(20),
as that takes care of the special cases, and never returns 0."

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up lfs/adaptive mount option

This patch removes F2FS_MOUNT_ADAPTIVE and F2FS_MOUNT_LFS mount options,
and add F2FS_OPTION.fs_mode with below two status to indicate filesystem
mode.

enum {
FS_MODE_ADAPTIVE, /* use both lfs/ssr allocation */
FS_MODE_LFS, /* use lfs allocation only */
};

It can enhance code readability and fs mode's scalability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up codes with {f2fs_,}data_blkaddr()

- rename datablock_addr() to data_blkaddr().
- wrap data_blkaddr() with f2fs_data_blkaddr() to clean up
parameters.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix inconsistent comments

Lack of maintenance on comments may mislead developers, fix them.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: cover last_disk_size update with spinlock

This change solves below hangtask issue:

INFO: task kworker/u16:1:58 blocked for more than 122 seconds.
Not tainted 5.6.0-rc2-00590-g9983bdae4974e #11
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u16:1 D 0 58 2 0x00000000
Workqueue: writeback wb_workfn (flush-179:0)
Backtrace:
(__schedule) from [<c0913234>] (schedule+0x78/0xf4)
(schedule) from [<c017ec74>] (rwsem_down_write_slowpath+0x24c/0x4c0)
(rwsem_down_write_slowpath) from [<c0915f2c>] (down_write+0x6c/0x70)
(down_write) from [<c0435b80>] (f2fs_write_single_data_page+0x608/0x7ac)
(f2fs_write_single_data_page) from [<c0435fd8>] (f2fs_write_cache_pages+0x2b4/0x7c4)
(f2fs_write_cache_pages) from [<c043682c>] (f2fs_write_data_pages+0x344/0x35c)
(f2fs_write_data_pages) from [<c0267ee8>] (do_writepages+0x3c/0xd4)
(do_writepages) from [<c0310cbc>] (__writeback_single_inode+0x44/0x454)
(__writeback_single_inode) from [<c03112d0>] (writeback_sb_inodes+0x204/0x4b0)
(writeback_sb_inodes) from [<c03115cc>] (__writeback_inodes_wb+0x50/0xe4)
(__writeback_inodes_wb) from [<c03118f4>] (wb_writeback+0x294/0x338)
(wb_writeback) from [<c0312dac>] (wb_workfn+0x35c/0x54c)
(wb_workfn) from [<c014f2b8>] (process_one_work+0x214/0x544)
(process_one_work) from [<c014f634>] (worker_thread+0x4c/0x574)
(worker_thread) from [<c01564fc>] (kthread+0x144/0x170)
(kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)

Reported-and-tested-by: Ondřej Jirman <megi@xff.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs: Enable bmap() function to properly return errors

By now, bmap() will either return the physical block number related to
the requested file offset or 0 in case of error or the requested offset
maps into a hole.
This patch makes the needed changes to enable bmap() to proper return
errors, using the return value as an error return, and now, a pointer
must be passed to bmap() to be filled with the mapped physical block.

It will change the behavior of bmap() on return:

- negative value in case of error
- zero on success or map fell into a hole

In case of a hole, the *block will be zero too

Since this is a prep patch, by now, the only error return is -EINVAL if
->bmap doesn't exist.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

f2fs: fix deadlock allocating bio_post_read_ctx from mempool

Without any form of coordination, any case where multiple allocations
from the same mempool are needed at a time to make forward progress can
deadlock under memory pressure.

This is the case for struct bio_post_read_ctx, as one can be allocated
to decrypt a Merkle tree page during fsverity_verify_bio(), which itself
is running from a post-read callback for a data bio which has its own
struct bio_post_read_ctx.

Fix this by freeing first bio_post_read_ctx before calling
fsverity_verify_bio(). This works because verity (if enabled) is always
the last post-read step.

This deadlock can be reproduced by trying to read from an encrypted
verity file after reducing NUM_PREALLOC_POST_READ_CTXS to 1 and patching
mempool_alloc() to pretend that pool->alloc() always fails.

Note that since NUM_PREALLOC_POST_READ_CTXS is actually 128, to actually
hit this bug in practice would require reading from lots of encrypted
verity files at the same time. But it's theoretically possible, as N
available objects doesn't guarantee forward progress when > N/2 threads
each need 2 objects at a time.

Fixes: 95ae251fe828 ("f2fs: add fs-verity support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove unneeded check for error allocating bio_post_read_ctx

Since allocating an object from a mempool never fails when
__GFP_DIRECT_RECLAIM (which is included in GFP_NOFS) is set, the check
for failure to allocate a bio_post_read_ctx is unnecessary. Remove it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to add swap extent correctly

As Youling reported in mailing list:

https://www.linuxquestions.org/questions/linux-newbie-8/the-file-system-f2fs-is-broken-4175666043/

https://www.linux.org/threads/the-file-system-f2fs-is-broken.26490/

There is a test case can corrupt f2fs image:
- dd if=/dev/zero of=/swapfile bs=1M count=4096
- chmod 600 /swapfile
- mkswap /swapfile
- swapon --discard /swapfile

The root cause is f2fs_swap_activate() intends to return zero value
to setup_swap_extents() to enable SWP_FS mode (swap file goes through
fs), in this flow, setup_swap_extents() setups swap extent with wrong
block address range, result in discard_swap() erasing incorrect address.

Because f2fs_swap_activate() has pinned swapfile, its data block
address will not change, it's safe to let swap to handle IO through
raw device, so we can get rid of SWAP_FS mode and initial swap extents
inside f2fs_swap_activate(), by this way, later discard_swap() can trim
in right address range.

Fixes: 4969c06a0d83 ("f2fs: support swap file w/ DIO")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support data compression

This patch tries to support compression in f2fs.

- New term named cluster is defined as basic unit of compression, file can
be divided into multiple clusters logically. One cluster includes 4 << n
(n >= 0) logical pages, compression size is also cluster size, each of
cluster can be compressed or not.

- In cluster metadata layout, one special flag is used to indicate cluster
is compressed one or normal one, for compressed cluster, following metadata
maps cluster to [1, 4 << n - 1] physical blocks, in where f2fs stores
data including compress header and compressed data.

- In order to eliminate write amplification during overwrite, F2FS only
support compression on write-once file, data can be compressed only when
all logical blocks in file are valid and cluster compress ratio is lower
than specified threshold.

- To enable compression on regular inode, there are three ways:
* chattr +c file
* chattr +c dir; touch dir/file
* mount w/ -o compress_extension=ext; touch file.ext

Compress metadata layout:
[Dnode Structure]
+-----------------------------------------------+
| cluster 1 | cluster 2 | ......... | cluster N |
+-----------------------------------------------+
. . . .
. . . .
. Compressed Cluster . . Normal Cluster .
+----------+---------+---------+---------+ +---------+---------+---------+---------+
|compr flag| block 1 | block 2 | block 3 | | block 1 | block 2 | block 3 | block 4 |
+----------+---------+---------+---------+ +---------+---------+---------+---------+
. .
. .
. .
+-------------+-------------+----------+----------------------------+
| data length | data chksum | reserved | compressed data |
+-------------+-------------+----------+----------------------------+

Changelog:

20190326:
- fix error handling of read_end_io().
- remove unneeded comments in f2fs_encrypt_one_page().

20190327:
- fix wrong use of f2fs_cluster_is_full() in f2fs_mpage_readpages().
- don't jump into loop directly to avoid uninitialized variables.
- add TODO tag in error path of f2fs_write_cache_pages().

20190328:
- fix wrong merge condition in f2fs_read_multi_pages().
- check compressed file in f2fs_post_read_required().

20190401
- allow overwrite on non-compressed cluster.
- check cluster meta before writing compressed data.

20190402
- don't preallocate blocks for compressed file.

- add lz4 compress algorithm
- process multiple post read works in one workqueue
Now f2fs supports processing post read work in multiple workqueue,
it shows low performance due to schedule overhead of multiple
workqueue executing orderly.

20190921
- compress: support buffered overwrite
C: compress cluster flag
V: valid block address
N: NEW_ADDR

One cluster contain 4 blocks

before overwrite after overwrite

- VVVV -> CVNN
- CVNN -> VVVV

- CVNN -> CVNN
- CVNN -> CVVV

- CVVV -> CVNN
- CVVV -> CVVV

20191029
- add kconfig F2FS_FS_COMPRESSION to isolate compression related
codes, add kconfig F2FS_FS_{LZO,LZ4} to cover backend algorithm.
note that: will remove lzo backend if Jaegeuk agreed that too.
- update codes according to Eric's comments.

20191101
- apply fixes from Jaegeuk

20191113
- apply fixes from Jaegeuk
- split workqueue for fsverity

20191216
- apply fixes from Jaegeuk

20200117
- fix to avoid NULL pointer dereference

[Jaegeuk Kim]
- add tracepoint for f2fs_{,de}compress_pages()
- fix many bugs and add some compression stats
- fix overwrite/mmap bugs
- address 32bit build error, reported by Geert.
- bug fixes when handling errors and i_compressed_blocks

Reported-by: <noreply@ellerman.id.au>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce private bioset

In low memory scenario, we can allocate multiple bios without
submitting any of them.

- f2fs_write_checkpoint()
- block_operations()
- f2fs_sync_node_pages()
step 1) flush cold nodes, allocate new bio from mempool
- bio_alloc()
- mempool_alloc()
step 2) flush hot nodes, allocate a bio from mempool
- bio_alloc()
- mempool_alloc()
step 3) flush warm nodes, be stuck in below call path
- bio_alloc()
- mempool_alloc()
- loop to wait mempool element release, as we only
reserved memory for two bio allocation, however above
allocated two bios may never be submitted.

So we need avoid using default bioset, in this patch we introduce a
private bioset, in where we enlarg mempool element count to total
number of log header, so that we can make sure we have enough
backuped memory pool in scenario of allocating/holding multiple
bios.

Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs-verity: implement readahead of Merkle tree pages

When fs-verity verifies data pages, currently it reads each Merkle tree
page synchronously using read_mapping_page().

Therefore, when the Merkle tree pages aren't already cached, fs-verity
causes an extra 4 KiB I/O request for every 512 KiB of data (assuming
that the Merkle tree uses SHA-256 and 4 KiB blocks). This results in
more I/O requests and performance loss than is strictly necessary.

Therefore, implement readahead of the Merkle tree pages.

For simplicity, we take advantage of the fact that the kernel already
does readahead of the file's *data*, just like it does for any other
file. Due to this, we don't really need a separate readahead state
(struct file_ra_state) just for the Merkle tree, but rather we just need
to piggy-back on the existing data readahead requests.

We also only really need to bother with the first level of the Merkle
tree, since the usual fan-out factor is 128, so normally over 99% of
Merkle tree I/O requests are for the first level.

Therefore, make fsverity_verify_bio() enable readahead of the first
Merkle tree level, for up to 1/4 the number of pages in the bio, when it
sees that the REQ_RAHEAD flag is set on the bio. The readahead size is
then passed down to ->read_merkle_tree_page() for the filesystem to
(optionally) implement if it sees that the requested page is uncached.

While we're at it, also make build_merkle_tree_level() set the Merkle
tree readahead size, since it's easy to do there.

However, for now don't set the readahead size in fsverity_verify_page(),
since currently it's only used to verify holes on ext4 and f2fs, and it
would need parameters added to know how much to read ahead.

This patch significantly improves fs-verity sequential read performance.
Some quick benchmarks with 'cat'-ing a 250MB file after dropping caches:

On an ARM64 phone (using sha256-ce):
Before: 217 MB/s
After: 263 MB/s
(compare to sha256sum of non-verity file: 357 MB/s)

In an x86_64 VM (using sha256-avx2):
Before: 173 MB/s
After: 215 MB/s
(compare to sha256sum of non-verity file: 223 MB/s)

Link: https://lore.kernel.org/r/20200106205533.137005-1-ebiggers@kernel.org
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>

f2fs: keep quota data on write_begin failure

This patch avoids some unnecessary locks for quota files when write_begin
fails.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: preallocate DIO blocks when forcing buffered_io

The previous preallocation and DIO decision like below.

allow_outplace_dio !allow_outplace_dio
f2fs_force_buffered_io (*) No_Prealloc / Buffered_IO Prealloc / Buffered_IO
!f2fs_force_buffered_io No_Prealloc / DIO Prealloc / DIO

But, Javier reported Case (*) where zoned device bypassed preallocation but
fell back to buffered writes in f2fs_direct_IO(), resulting in stale data
being read.

In order to fix the issue, actually we need to preallocate blocks whenever
we fall back to buffered IO like this. No change is made in the other cases.

allow_outplace_dio !allow_outplace_dio
f2fs_force_buffered_io (*) Prealloc / Buffered_IO Prealloc / Buffered_IO
!f2fs_force_buffered_io No_Prealloc / DIO Prealloc / DIO

Reported-and-tested-by: Javier Gonzalez <javier@javigon.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: show f2fs instance in printk_ratelimited

As Eric mentioned, bare printk{,_ratelimited} won't show which
filesystem instance these message is coming from, this patch tries
to show fs instance with sb->s_id field in all places we missed
before.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix potential overflow

We expect 64-bit calculation result from below statement, however
in 32-bit machine, looped left shift operation on pgoff_t type
variable may cause overflow issue, fix it by forcing type cast.

page->index << PAGE_SHIFT;

Fixes: 26de9b117130 ("f2fs: avoid unnecessary updating inode during fsync")
Fixes: 0a2aa8fbb969 ("f2fs: refactor __exchange_data_block for speed up")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: cache global IPU bio

In commit 8648de2c581e ("f2fs: add bio cache for IPU"), we added
f2fs_submit_ipu_bio() in __write_data_page() as below:

__write_data_page()

if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode)) {
f2fs_submit_ipu_bio(sbi, bio, page);
....
}

in order to avoid below deadlock:

Thread A Thread B
- __write_data_page (inode x, page y)
- f2fs_do_write_data_page
- set_page_writeback ---- set writeback flag in page y
- f2fs_inplace_write_data
- f2fs_balance_fs
- lock gc_mutex
- lock gc_mutex
- f2fs_gc
- do_garbage_collect
- gc_data_segment
- move_data_page
- f2fs_wait_on_page_writeback
- wait_on_page_writeback --- wait writeback of page y

However, the bio submission breaks the merge of IPU IOs.

So in this patch let's add a global bio cache for merged IPU pages,
then f2fs_wait_on_page_writeback() is able to submit bio if a
writebacked page is cached in global bio cache.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to add missing F2FS_IO_ALIGNED() condition

In f2fs_allocate_data_block(), we will reset fio.retry for IO
alignment feature instead of IO serialization feature.

In addition, spread F2FS_IO_ALIGNED() to check IO alignment
feature status explicitly.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to handle error path correctly in f2fs_map_blocks

In f2fs_map_blocks(), we should bail out once __allocate_data_block()
failed.

Fixes: f847c699cff3 ("f2fs: allow out-place-update for direct IO in LFS mode")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix extent corrupotion during directIO in LFS mode

In LFS mode, por_fsstress testcase reports a bug as below:

[ASSERT] (fsck_chk_inode_blk: 931) --> ino: 0x12fe has wrong ext: [pgofs:142, blk:215424, len:16]

Since commit f847c699cff3 ("f2fs: allow out-place-update for direct
IO in LFS mode"), we start to allow OPU mode for direct IO, however,
we missed to update extent cache in __allocate_data_block(), finally,
it cause extent field being inconsistent with physical block address,
fix it.

Fixes: f847c699cff3 ("f2fs: allow out-place-update for direct IO in LFS mode")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: enhance f2fs_is_checkpoint_ready()'s readability

This patch changes sematics of f2fs_is_checkpoint_ready()'s return
value as: return true when checkpoint is ready, other return false,
it can improve readability of below conditions.

f2fs_submit_page_write()
...
if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) ||
!f2fs_is_checkpoint_ready(sbi))
__submit_merged_bio(io);

f2fs_balance_fs()
...
if (!f2fs_is_checkpoint_ready(sbi))
return;

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clean up __bio_alloc()'s parameter

Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support fiemap() for directory inode

Adjust f2fs_fiemap() to support fiemap() on directory inode.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix panic of IO alignment feature

Since 07173c3ec276 ("block: enable multipage bvecs"), one bio vector
can store multi pages, so that we can not calculate max IO size of
bio as PAGE_SIZE * bio->bi_max_vecs. However IO alignment feature of
f2fs always has that assumption, so finally, it may cause panic during
IO submission as below stack.

kernel BUG at fs/f2fs/data.c:317!
RIP: 0010:__submit_merged_bio+0x8b0/0x8c0
Call Trace:
f2fs_submit_page_write+0x3cd/0xdd0
do_write_page+0x15d/0x360
f2fs_outplace_write_data+0xd7/0x210
f2fs_do_write_data_page+0x43b/0xf30
__write_data_page+0xcf6/0x1140
f2fs_write_cache_pages+0x3ba/0xb40
f2fs_write_data_pages+0x3dd/0x8b0
do_writepages+0xbb/0x1e0
__writeback_single_inode+0xb6/0x800
writeback_sb_inodes+0x441/0x910
wb_writeback+0x261/0x650
wb_workfn+0x1f9/0x7a0
process_one_work+0x503/0x970
worker_thread+0x7d/0x820
kthread+0x1ad/0x210
ret_from_fork+0x35/0x40

This patch adds one extra condition to check left space in bio while
trying merging page to bio, to avoid panic.

This bug was reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=204043

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce {page,io}_is_mergeable() for readability

Wrap merge condition into function for readability, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix livelock in swapfile writes

This patch fixes livelock in the below call path when writing swap pages.

[46374.617256] c2 701 __switch_to+0xe4/0x100
[46374.617265] c2 701 __schedule+0x80c/0xbc4
[46374.617273] c2 701 schedule+0x74/0x98
[46374.617281] c2 701 rwsem_down_read_failed+0x190/0x234
[46374.617291] c2 701 down_read+0x58/0x5c
[46374.617300] c2 701 f2fs_map_blocks+0x138/0x9a8
[46374.617310] c2 701 get_data_block_dio_write+0x74/0x104
[46374.617320] c2 701 __blockdev_direct_IO+0x1350/0x3930
[46374.617331] c2 701 f2fs_direct_IO+0x55c/0x8bc
[46374.617341] c2 701 __swap_writepage+0x1d0/0x3e8
[46374.617351] c2 701 swap_writepage+0x44/0x54
[46374.617360] c2 701 shrink_page_list+0x140/0xe80
[46374.617371] c2 701 shrink_inactive_list+0x510/0x918
[46374.617381] c2 701 shrink_node_memcg+0x2d4/0x804
[46374.617391] c2 701 shrink_node+0x10c/0x2f8
[46374.617400] c2 701 do_try_to_free_pages+0x178/0x38c
[46374.617410] c2 701 try_to_free_pages+0x348/0x4b8
[46374.617419] c2 701 __alloc_pages_nodemask+0x7f8/0x1014
[46374.617429] c2 701 pagecache_get_page+0x184/0x2cc
[46374.617438] c2 701 f2fs_new_node_page+0x60/0x41c
[46374.617449] c2 701 f2fs_new_inode_page+0x50/0x7c
[46374.617460] c2 701 f2fs_init_inode_metadata+0x128/0x530
[46374.617472] c2 701 f2fs_add_inline_entry+0x138/0xd64
[46374.617480] c2 701 f2fs_do_add_link+0xf4/0x178
[46374.617488] c2 701 f2fs_create+0x1e4/0x3ac
[46374.617497] c2 701 path_openat+0xdc0/0x1308
[46374.617507] c2 701 do_filp_open+0x78/0x124
[46374.617516] c2 701 do_sys_open+0x134/0x248
[46374.617525] c2 701 SyS_openat+0x14/0x20

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add fs-verity support

Add fs-verity support to f2fs. fs-verity is a filesystem feature that
enables transparent integrity protection and authentication of read-only
files. It uses a dm-verity like mechanism at the file level: a Merkle
tree is used to verify any block in the file in log(filesize) time. It
is implemented mainly by helper functions in fs/verity/. See
Documentation/filesystems/fsverity.rst for the full documentation.

The f2fs support for fs-verity consists of:

- Adding a filesystem feature flag and an inode flag for fs-verity.

- Implementing the fsverity_operations to support enabling verity on an
inode and reading/writing the verity metadata.

- Updating ->readpages() to verify data as it's read from verity files
and to support reading verity metadata pages.

- Updating ->write_begin(), ->write_end(), and ->writepages() to support
writing verity metadata pages.

- Calling the fs-verity hooks for ->open(), ->setattr(), and ->ioctl().

Like ext4, f2fs stores the verity metadata (Merkle tree and
fsverity_descriptor) past the end of the file, starting at the first 64K
boundary beyond i_size. This approach works because (a) verity files
are readonly, and (b) pages fully beyond i_size aren't visible to
userspace but can be read/written internally by f2fs with only some
relatively small changes to f2fs. Extended attributes cannot be used
because (a) f2fs limits the total size of an inode's xattr entries to
4096 bytes, which wouldn't be enough for even a single Merkle tree
block, and (b) f2fs encryption doesn't encrypt xattrs, yet the verity
metadata *must* be encrypted when the file is because it contains hashes
of the plaintext data.

Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

mm: migrate: remove unused mode argument

migrate_page_move_mapping() doesn't use the mode argument. Remove it
and update callers accordingly.

Link: http://lkml.kernel.org/r/20190508210301.8472-1-keith.busch@intel.com
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

blkcg, writeback: Rename wbc_account_io() to wbc_account_cgroup_owner()

wbc_account_io() does a very specific job - try to see which cgroup is
actually dirtying an inode and transfer its ownership to the majority
dirtier if needed. The name is too generic and confusing. Let's
rename it to something more specific.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: support swap file w/ DIO

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use generic EFSBADCRC/EFSCORRUPTED

f2fs uses EFAULT as error number to indicate filesystem is corrupted
all the time, but generic filesystems use EUCLEAN for such condition,
we need to change to follow others.

This patch adds two new macros as below to wrap more generic error
code macros, and spread them in code.

EFSBADCRC EBADMSG /* Bad CRC detected */
EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */

Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fscrypt: support encrypting multiple filesystem blocks per page

Rename fscrypt_encrypt_page() to fscrypt_encrypt_pagecache_blocks() and
redefine its behavior to encrypt all filesystem blocks from the given
region of the given page, rather than assuming that the region consists
of just one filesystem block. Also remove the 'inode' and 'lblk_num'
parameters, since they can be retrieved from the page as it's already
assumed to be a pagecache page.

This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.

This is based on work by Chandan Rajendra.

Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

fscrypt: simplify bounce page handling

Currently, bounce page handling for writes to encrypted files is
unnecessarily complicated. A fscrypt_ctx is allocated along with each
bounce page, page_private(bounce_page) points to this fscrypt_ctx, and
fscrypt_ctx::w::control_page points to the original pagecache page.

However, because writes don't use the fscrypt_ctx for anything else,
there's no reason why page_private(bounce_page) can't just point to the
original pagecache page directly.

Therefore, this patch makes this change. In the process, it also cleans
up the API exposed to filesystems that allows testing whether a page is
a bounce page, getting the pagecache page from a bounce page, and
freeing a bounce page.

Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

f2fs: fix to avoid deadloop if data_flush is on

As Hagbard Celine reported:

[ 615.697824] INFO: task kworker/u16:5:344 blocked for more than 120 seconds.
[ 615.697825] Not tainted 5.0.15-gentoo-f2fslog #4
[ 615.697826] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 615.697827] kworker/u16:5 D 0 344 2 0x80000000
[ 615.697831] Workqueue: writeback wb_workfn (flush-259:0)
[ 615.697832] Call Trace:
[ 615.697836] ? __schedule+0x2c5/0x8b0
[ 615.697839] schedule+0x32/0x80
[ 615.697841] schedule_preempt_disabled+0x14/0x20
[ 615.697842] __mutex_lock.isra.8+0x2ba/0x4d0
[ 615.697845] ? log_store+0xf5/0x260
[ 615.697848] f2fs_write_data_pages+0x133/0x320
[ 615.697851] ? trace_hardirqs_on+0x2c/0xe0
[ 615.697854] do_writepages+0x41/0xd0
[ 615.697857] __filemap_fdatawrite_range+0x81/0xb0
[ 615.697859] f2fs_sync_dirty_inodes+0x1dd/0x200
[ 615.697861] f2fs_balance_fs_bg+0x2a7/0x2c0
[ 615.697863] ? up_read+0x5/0x20
[ 615.697865] ? f2fs_do_write_data_page+0x2cb/0x940
[ 615.697867] f2fs_balance_fs+0xe5/0x2c0
[ 615.697869] __write_data_page+0x1c8/0x6e0
[ 615.697873] f2fs_write_cache_pages+0x1e0/0x450
[ 615.697878] f2fs_write_data_pages+0x14b/0x320
[ 615.697880] ? trace_hardirqs_on+0x2c/0xe0
[ 615.697883] do_writepages+0x41/0xd0
[ 615.697885] __filemap_fdatawrite_range+0x81/0xb0
[ 615.697887] f2fs_sync_dirty_inodes+0x1dd/0x200
[ 615.697889] f2fs_balance_fs_bg+0x2a7/0x2c0
[ 615.697891] f2fs_write_node_pages+0x51/0x220
[ 615.697894] do_writepages+0x41/0xd0
[ 615.697897] __writeback_single_inode+0x3d/0x3d0
[ 615.697899] writeback_sb_inodes+0x1e8/0x410
[ 615.697902] __writeback_inodes_wb+0x5d/0xb0
[ 615.697904] wb_writeback+0x28f/0x340
[ 615.697906] ? cpumask_next+0x16/0x20
[ 615.697908] wb_workfn+0x33e/0x420
[ 615.697911] process_one_work+0x1a1/0x3d0
[ 615.697913] worker_thread+0x30/0x380
[ 615.697915] ? process_one_work+0x3d0/0x3d0
[ 615.697916] kthread+0x116/0x130
[ 615.697918] ? kthread_create_worker_on_cpu+0x70/0x70
[ 615.697921] ret_from_fork+0x3a/0x50

There is still deadloop in below condition:

d A
- do_writepages
- f2fs_write_node_pages
- f2fs_balance_fs_bg
- f2fs_sync_dirty_inodes
- f2fs_write_cache_pages
- mutex_lock(&sbi->writepages) -- lock once
- __write_data_page
- f2fs_balance_fs_bg
- f2fs_sync_dirty_inodes
- f2fs_write_data_pages
- mutex_lock(&sbi->writepages) -- lock again

Thread A Thread B
- do_writepages
- f2fs_write_node_pages
- f2fs_balance_fs_bg
- f2fs_sync_dirty_inodes
- .cp_task = current
- f2fs_sync_dirty_inodes
- .cp_task = current
- filemap_fdatawrite
- .cp_task = NULL
- filemap_fdatawrite
- f2fs_write_cache_pages
- enter f2fs_balance_fs_bg since .cp_task is NULL
- .cp_task = NULL

Change as below to avoid this:
- add condition to avoid holding .writepages mutex lock in path
of data flush
- introduce mutex lock sbi.flush_lock to exclude concurrent data
flush in background.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add bio cache for IPU

SQLite in Wal mode may trigger sequential IPU write in db-wal file, after
commit d1b3e72d5490 ("f2fs: submit bio of in-place-update pages"), we
lost the chance of merging page in inner managed bio cache, result in
submitting more small-sized IO.

So let's add temporary bio in writepages() to cache mergeable write IO as
much as possible.

Test case:
1. xfs_io -f /mnt/f2fs/file -c "pwrite 0 65536" -c "fsync"
2. xfs_io -f /mnt/f2fs/file -c "pwrite 0 65536" -c "fsync"

Before:
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65544, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65552, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65560, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65568, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65576, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65584, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65592, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65600, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65608, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65616, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65624, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65632, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65640, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65648, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65656, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65664, size = 4096
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), NODE, sector = 57352, size = 4096

After:
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65544, size = 65536
f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), NODE, sector = 57368, size = 4096

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce DATA_GENERIC_ENHANCE

Previously, f2fs_is_valid_blkaddr(, blkaddr, DATA_GENERIC) will check
whether @blkaddr locates in main area or not.

That check is weak, since the block address in range of main area can
point to the address which is not valid in segment info table, and we
can not detect such condition, we may suffer worse corruption as system
continues running.

So this patch introduce DATA_GENERIC_ENHANCE to enhance the sanity check
which trigger SIT bitmap check rather than only range check.

This patch did below changes as wel:
- set SBI_NEED_FSCK in f2fs_is_valid_blkaddr().
- get rid of is_valid_data_blkaddr() to avoid panic if blkaddr is invalid.
- introduce verify_fio_blkaddr() to wrap fio {new,old}_blkaddr validation check.
- spread blkaddr check in:
* f2fs_get_node_info()
* __read_out_blkaddrs()
* f2fs_submit_page_read()
* ra_data_block()
* do_recover_data()

This patch can fix bug reported from bugzilla below:

https://bugzilla.kernel.org/show_bug.cgi?id=203215
https://bugzilla.kernel.org/show_bug.cgi?id=203223
https://bugzilla.kernel.org/show_bug.cgi?id=203231
https://bugzilla.kernel.org/show_bug.cgi?id=203235
https://bugzilla.kernel.org/show_bug.cgi?id=203241

= Update by Jaegeuk Kim =

DATA_GENERIC_ENHANCE enhanced to validate block addresses on read/write paths.
But, xfstest/generic/446 compalins some generated kernel messages saying invalid
bitmap was detected when reading a block. The reaons is, when we get the
block addresses from extent_cache, there is no lock to synchronize it from
truncating the blocks in parallel.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce f2fs_read_single_page() for cleanup

This patch introduces f2fs_read_single_page() to wrap core operations
of reading one page in f2fs_mpage_readpages().

In addition, if we failed in f2fs_mpage_readpages(), propagate error
number to f2fs_read_data_page(), for f2fs_read_data_pages() path,
always return success.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to set FI_UPDATE_WRITE correctly

This patch fixes to set FI_UPDATE_WRITE only if in-place IO was issued.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix wrong __is_meta_io() macro

This patch changes codes as below:
- don't use is_read_io() as a condition to judge the meta IO.
- use .is_por to replace .is_meta to indicate IO is from recovery explicitly.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

block: remove the i argument to bio_for_each_segment_all

We only have two callers that need the integer loop iterator, and they
can easily maintain it themselves.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

f2fs: data: fix warning Using plain integer as NULL pointer

changed passing function argument "0 to NULL" to fix below sparse
warning

fs/f2fs/data.c:426:47: warning: Using plain integer as NULL pointer

Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix potential recursive call when enabling data_flush

As Hagbard Celine reported:

Hi, this is a long standing bug that I've hit before on older kernels,
but I was not able to get the syslog saved because of the nature of
the bug. This time I had booted form a pen-drive, and was able to save
the log to it's efi-partition.
What i did to trigger it was to create a partition and format it f2fs,
then mount it with options:
"rw,relatime,lazytime,background_gc=on,disable_ext_identify,discard,heap,user_xattr,inline_xattr,acl,inline_data,inline_dentry,flush_merge,data_flush,extent_cache,mode=adaptive,active_logs=6,whint_mode=fs-based,alloc_mode=default,fsync_mode=strict".
Then I unpacked a big .tar.xz to the partition (I used a
gentoo-stage3-tarball as I was in process of installing Gentoo).

Same options just without data_flush gives no problems.

Mar 20 20:54:01 usbgentoo kernel: FAT-fs (nvme0n1p4): Volume was not
properly unmounted. Some data may be corrupt. Please run fsck.
Mar 20 21:05:23 usbgentoo kernel: kworker/dying (1588) used greatest
stack depth: 12064 bytes left
Mar 20 21:06:40 usbgentoo kernel: BUG: stack guard page was hit at
00000000a4b0733c (stack is 0000000056016422..0000000096e7463f)
Mar 20 21:06:40 usbgentoo kernel: kernel stack overflow

......

Mar 20 21:06:40 usbgentoo kernel: Call Trace:
Mar 20 21:06:40 usbgentoo kernel: read_node_page+0x71/0xf0
Mar 20 21:06:40 usbgentoo kernel: ? xas_load+0x8/0x50
Mar 20 21:06:40 usbgentoo kernel: __get_node_page+0x73/0x2a0
Mar 20 21:06:40 usbgentoo kernel: f2fs_get_dnode_of_data+0x34e/0x580
Mar 20 21:06:40 usbgentoo kernel: f2fs_write_inline_data+0x5e/0x2a0
Mar 20 21:06:40 usbgentoo kernel: __write_data_page+0x421/0x690
Mar 20 21:06:40 usbgentoo kernel: f2fs_write_cache_pages+0x1cf/0x460
Mar 20 21:06:40 usbgentoo kernel: f2fs_write_data_pages+0x2b3/0x2e0
Mar 20 21:06:40 usbgentoo kernel: ? f2fs_inode_chksum_verify+0x1d/0xc0
Mar 20 21:06:40 usbgentoo kernel: ? read_node_page+0x71/0xf0
Mar 20 21:06:40 usbgentoo kernel: do_writepages+0x3c/0xd0
Mar 20 21:06:40 usbgentoo kernel: __filemap_fdatawrite_range+0x7c/0xb0
Mar 20 21:06:40 usbgentoo kernel: f2fs_sync_dirty_inodes+0xf2/0x200
Mar 20 21:06:40 usbgentoo kernel: f2fs_balance_fs_bg+0x2a3/0x2c0
Mar 20 21:06:40 usbgentoo kernel: ? f2fs_inode_dirtied+0x21/0xc0
Mar 20 21:06:40 usbgentoo kernel: f2fs_balance_fs+0xd6/0x2b0
Mar 20 21:06:40 usbgentoo kernel: __write_data_page+0x4fb/0x690

......

Mar 20 21:06:40 usbgentoo kernel: __writeback_single_inode+0x2a1/0x340
Mar 20 21:06:40 usbgentoo kernel: ? soft_cursor+0x1b4/0x220
Mar 20 21:06:40 usbgentoo kernel: writeback_sb_inodes+0x1d5/0x3e0
Mar 20 21:06:40 usbgentoo kernel: __writeback_inodes_wb+0x58/0xa0
Mar 20 21:06:40 usbgentoo kernel: wb_writeback+0x250/0x2e0
Mar 20 21:06:40 usbgentoo kernel: ? 0xffffffff8c000000
Mar 20 21:06:40 usbgentoo kernel: ? cpumask_next+0x16/0x20
Mar 20 21:06:40 usbgentoo kernel: wb_workfn+0x2f6/0x3b0
Mar 20 21:06:40 usbgentoo kernel: ? __switch_to_asm+0x40/0x70
Mar 20 21:06:40 usbgentoo kernel: process_one_work+0x1f5/0x3f0
Mar 20 21:06:40 usbgentoo kernel: worker_thread+0x28/0x3c0
Mar 20 21:06:40 usbgentoo kernel: ? rescuer_thread+0x330/0x330
Mar 20 21:06:40 usbgentoo kernel: kthread+0x10e/0x130
Mar 20 21:06:40 usbgentoo kernel: ? kthread_create_on_node+0x60/0x60
Mar 20 21:06:40 usbgentoo kernel: ret_from_fork+0x35/0x40

The root cause is that we run into an infinite recursive calling in
between f2fs_balance_fs_bg and writepage() as described below:

- f2fs_write_data_pages --- A
- __write_data_page
- f2fs_balance_fs
- f2fs_balance_fs_bg --- B
- f2fs_sync_dirty_inodes
- filemap_fdatawrite
- f2fs_write_data_pages --- A
...
- f2fs_balance_fs_bg --- B
...

In order to fix this issue, let's detect such condition in __write_data_page()
and just skip calling f2fs_balance_fs() recursively.

Reported-by: Hagbard Celine <hagbardcelin@gmail.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>