kernel/linux.git/fs/jbd2/revoke.c, branch linux-7.1.y

jbd2: fix deadlock in jbd2_journal_cancel_revoke()

2026-04-10T02:09:39+00:00

Commit f76d4c28a46a ("fs/jbd2: use sleeping version of __find_get_block()") changed jbd2_journal_cancel_revoke() to use __find_get_block_nonatomic() which holds the folio lock instead of i_private_lock. This breaks the lock ordering (folio -> buffer) and causes an ABBA deadlock when the filesystem blocksize < pagesize: T1 T2 ext4_mkdir() ext4_init_new_dir() ext4_append() ext4_getblk() lock_buffer() <- A sync_blockdev() blkdev_writepages() writeback_iter() writeback_get_folio() folio_lock() <- B ext4_journal_get_create_access() jbd2_journal_cancel_revoke() __find_get_block_nonatomic() folio_lock() <- B block_write_full_folio() lock_buffer() <- A This can occasionally cause generic/013 to hang. Fix by only calling __find_get_block_nonatomic() when the passed buffer_head doesn't belong to the bdev, which is the only case that we need to look up its bdev alias. Otherwise, the lookup is redundant since the found buffer_head is equal to the one we passed in. Fixes: f76d4c28a46a ("fs/jbd2: use sleeping version of __find_get_block()") Signed-off-by: Zhang Yi Link: https://patch.msgid.link/20260409114204.917154-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

fs/jbd2: use sleeping version of __find_get_block()

2025-04-22T16:16:08+00:00

Convert to the new nonatomic flavor to benefit from potential performance benefits and adapt in the future vs migration such that semantics are kept. - jbd2_journal_revoke(): can sleep (has might_sleep() in the beginning) - jbd2_journal_cancel_revoke(): only used from do_get_write_access() and do_get_create_access() which do sleep. So can sleep. - jbd2_clear_buffer_revoked_flags() - only called from journal commit code which sleeps. So can sleep. Suggested-by: Jan Kara Reviewed-by: Jan Kara Signed-off-by: Davidlohr Bueso Link: https://kdevops.org/ext4/v6.15-rc2.html # [0] Link: https://lore.kernel.org/all/aAAEvcrmREWa1SKF@bombadil.infradead.org/ # [1] Link: https://lore.kernel.org/20250418015921.132400-6-dave@stgolabs.net Tested-by: kdevops@lists.linux.dev Reviewed-by: Luis Chamberlain Signed-off-by: Christian Brauner

jbd2: correct stale function name in comment

2025-03-13T14:41:21+00:00

Rename stale journal_clear_revoked_flag to jbd2_clear_buffer_revoked_flags. Rename stale journal_switch_revoke to jbd2_journal_switch_revoke_table. Rename stale __journal_file_buffer to __jbd2_journal_file_buffer. Signed-off-by: Kemeng Shi Reviewed-by: Jan Kara Reviewed-by: Zhang Yi Link: https://patch.msgid.link/20250123155014.2097920-6-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o

jbd2: remove unused return value of jbd2_journal_cancel_revoke

2025-03-13T14:41:21+00:00

Remove unused return value of jbd2_journal_cancel_revoke. Signed-off-by: Kemeng Shi Reviewed-by: Jan Kara Reviewed-by: Zhang Yi Link: https://patch.msgid.link/20250123155014.2097920-3-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o

jbd2: Avoid long replay times due to high number or revoke blocks

2025-02-13T05:19:10+00:00

Some users are reporting journal replay takes a long time when there is excessive number of revoke blocks in the journal. Reported times are like: 1048576 records - 95 seconds 2097152 records - 580 seconds The problem is that hash chains in the revoke table gets excessively long in these cases. Fix the problem by sizing the revoke table appropriately before the revoke pass. Thanks to Alexey Zhuravlev for benchmarking the patch with large numbers of revoke blocks [1]. [1] https://lore.kernel.org/all/20250113183107.7bfef7b6@x390.bzzz77.ru Signed-off-by: Jan Kara Reviewed-by: Andreas Dilger Reviewed-by: Zhang Yi Link: https://patch.msgid.link/20250121140925.17231-2-jack@suse.cz Signed-off-by: Theodore Ts'o

jbd2: increase IO priority for writing revoke records

2024-12-04T11:00:05+00:00

Commit '6a3afb6ac6df ("jbd2: increase the journal IO's priority")' increases the priority of journal I/O by marking I/O with the JBD2_JOURNAL_REQ_FLAGS. However, that commit missed the revoke buffers, so also addresses that kind of I/Os. Fixes: 6a3afb6ac6df ("jbd2: increase the journal IO's priority") Signed-off-by: Zhang Yi Link: https://lore.kernel.org/r/20241203014407.805916-2-yi.zhang@huaweicloud.com Reviewed-by: Kemeng Shi Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

jbd2: rename jbd_debug() to jbd2_debug()

2022-08-03T03:52:19+00:00

The name of jbd_debug() is confusing as all functions inside jbd2 have jbd2_ prefix. Rename jbd_debug() to jbd2_debug(). No functional changes. Signed-off-by: Jan Kara Reviewed-by: Lukas Czerner Link: https://lore.kernel.org/r/20220608112355.4397-2-jack@suse.cz Signed-off-by: Theodore Ts'o

jbd2: Reserve space for revoke descriptor blocks

2019-11-05T21:00:48+00:00

Extend functions for starting, extending, and restarting transaction handles to take number of revoke records handle must be able to accommodate. These functions then make sure transaction has enough credits to be able to store resulting revoke descriptor blocks. Also revoke code tracks number of revoke records created by a handle to catch situation where some place didn't reserve enough space for revoke records. Similarly to standard transaction credits, space for unused reserved revoke records is released when the handle is stopped. On the ext4 side we currently take a simplistic approach of reserving space for 1024 revoke records for any transaction. This grows amount of credits reserved for each handle only by a few and is enough for any normal workload so that we don't hit warnings in jbd2. We will refine the logic in following commits. Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191105164437.32602-20-jack@suse.cz Signed-off-by: Theodore Ts'o