kernel/git/stable/linux-stable.git/fs/ext4/ext4_jbd2.h, branch master

ext4: enable scoped NOFS when starting a handle in nojournal mode

2026-07-23T03:47:06+00:00

The jbd2 layer enables NOFS mode using memalloc_nofs_{save,restore}() while a handle is active. We need to do the same in nojournal mode so that it is safe to remove GFP_NOFS flags while a jbd2 handle is active. This will require that we actually allocate a real handle, but with an h_invalid flag set, so there is a place to put the saved memalloc context. Signed-off-by: Theodore Ts'o Reviewed-by: Andreas Dilger

ext4/jbd2: convert jbd2_journal_blocks_per_page() to support large folio

2025-05-20T14:31:12+00:00

jbd2_journal_blocks_per_page() returns the number of blocks in a single page. Rename it to jbd2_journal_blocks_per_folio() and make it returns the number of blocks in the largest folio, preparing for the calculation of journal credits blocks when allocating blocks within a large folio in the writeback path. Signed-off-by: Zhang Yi Link: https://patch.msgid.link/20250512063319.3539411-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o

ext4: avoid journaling sb update on error if journal is destroying

2025-03-21T05:12:33+00:00

Presently we always BUG_ON if trying to start a transaction on a journal marked with JBD2_UNMOUNT, since this should never happen. However, while ltp running stress tests, it was observed that in case of some error handling paths, it is possible for update_super_work to start a transaction after the journal is destroyed eg: (umount) ext4_kill_sb kill_block_super generic_shutdown_super sync_filesystem /* commits all txns */ evict_inodes /* might start a new txn */ ext4_put_super flush_work(&sbi->s_sb_upd_work) /* flush the workqueue */ jbd2_journal_destroy journal_kill_thread journal->j_flags |= JBD2_UNMOUNT; jbd2_journal_commit_transaction jbd2_journal_get_descriptor_buffer jbd2_journal_bmap ext4_journal_bmap ext4_map_blocks ... ext4_inode_error ext4_handle_error schedule_work(&sbi->s_sb_upd_work) /* work queue kicks in */ update_super_work jbd2_journal_start start_this_handle BUG_ON(journal->j_flags & JBD2_UNMOUNT) Hence, introduce a new mount flag to indicate journal is destroying and only do a journaled (and deferred) update of sb if this flag is not set. Otherwise, just fallback to an un-journaled commit. Further, in the journal destroy path, we have the following sequence: 1. Set mount flag indicating journal is destroying 2. force a commit and wait for it 3. flush pending sb updates This sequence is important as it ensures that, after this point, there is no sb update that might be journaled so it is safe to update the sb outside the journal. (To avoid race discussed in 2d01ddc86606) Also, we don't need a similar check in ext4_grp_locked_error since it is only called from mballoc and AFAICT it would be always valid to schedule work here. Fixes: 2d01ddc86606 ("ext4: save error info to sb through journal if available") Reported-by: Mahesh Kumar Signed-off-by: Ojaswin Mujoo Reviewed-by: Jan Kara Link: https://patch.msgid.link/9613c465d6ff00cd315602f99283d5f24018c3f7.1742279837.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o

ext4: define ext4_journal_destroy wrapper

2025-03-21T05:12:33+00:00

Define an ext4 wrapper over jbd2_journal_destroy to make sure we have consistent behavior during journal destruction. This will also come useful in the next patch where we add some ext4 specific logic in the destroy path. Reviewed-by: Jan Kara Reviewed-by: Baokun Li Signed-off-by: Ojaswin Mujoo Link: https://patch.msgid.link/c3ba78c5c419757e6d5f2d8ebb4a8ce9d21da86a.1742279837.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o

ext4: remove unused ext4 journal callback

2025-02-10T12:48:24+00:00

Remove unused ext4 journal callback. Signed-off-by: Kemeng Shi Reviewed-by: Zhang Yi Reviewed-by: Jan Kara Link: https://patch.msgid.link/20241218145414.1422946-2-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o

ext4: split ext4_journal_start trace for debug

2022-12-01T15:46:54+00:00

we might want to know why jbd2 thread using high io for detail, split ext4_journal_start trace to ext4_journal_start_sb and ext4_journal_start_inode, show ino and handle type when possible. Signed-off-by: changfengnan Link: https://lore.kernel.org/r/20221008120518.74870-1-changfengnan@bytedance.com Signed-off-by: Theodore Ts'o

fs/ext4: fix comments mentioning i_mutex

2022-02-03T15:57:53+00:00

inode->i_mutex has been replaced with inode->i_rwsem long ago. Fix comments still mentioning i_mutex. Signed-off-by: hongnanli Link: https://lore.kernel.org/r/20220121070611.21618-1-hongnan.li@linux.alibaba.com Signed-off-by: Theodore Ts'o

ext4: Support for checksumming from journal triggers

2021-08-31T03:36:50+00:00

JBD2 layer support triggers which are called when journaling layer moves buffer to a certain state. We can use the frozen trigger, which gets called when buffer data is frozen and about to be written out to the journal, to compute block checksums for some buffer types (similarly as does ocfs2). This avoids unnecessary repeated recomputation of the checksum (at the cost of larger window where memory corruption won't be caught by checksumming) and is even necessary when there are unsynchronized updaters of the checksummed data. So add superblock and journal trigger type arguments to ext4_journal_get_write_access() and ext4_journal_get_create_access() so that frozen triggers can be set accordingly. Also add inode argument to ext4_walk_page_buffers() and all the callbacks used with that function for the same purpose. This patch is mostly only a change of prototype of the above mentioned functions and a few small helpers. Real checksumming will come later. Reviewed-by: Theodore Ts'o Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20210816095713.16537-1-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: drop ext4_handle_dirty_super()

2020-12-22T18:08:46+00:00

The wrapper is now useless since it does what ext4_handle_dirty_metadata() does. Just remove it. Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20201216101844.22917-9-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: add helpers for checking whether quota can be enabled/is journalled

2020-12-03T14:18:48+00:00

Right now, there are several places, where we check whether fs is capable of enabling quota or if quota is journalled with quite long and non-self-descriptive condition statements. This patch wraps these statements into helpers for better readability and easier usage. Link: https://lore.kernel.org/r/1603336860-16153-1-git-send-email-dotdot@yandex-team.ru Reviewed-by: Jan Kara Signed-off-by: Roman Anufriev Signed-off-by: Theodore Ts'o