linux-stable.git/fs/ext4/fast_commit.c, branch v5.12

ext4: fix rename whiteout with fast commit

2021-03-21T04:38:18+00:00

This patch adds rename whiteout support in fast commits. Note that the
whiteout object that gets created is actually char device. Which
imples, the function ext4_inode_journal_mode(struct inode *inode)
would return "JOURNAL_DATA" for this inode. This has a consequence in
fast commit code that it will make creation of the whiteout object a
fast-commit ineligible behavior and thus will fall back to full
commits. With this patch, this can be observed by running fast commits
with rename whiteout and seeing the stats generated by ext4_fc_stats
tracepoint as follows:

ext4_fc_stats: dev 254:32 fc ineligible reasons:
XATTR:0, CROSS_RENAME:0, JOURNAL_FLAG_CHANGE:0, NO_MEM:0, SWAP_BOOT:0,
RESIZE:0, RENAME_DIR:0, FALLOC_RANGE:0, INODE_JOURNAL_DATA:16;
num_commits:6, ineligible: 6, numblks: 3

So in short, this patch guarantees that in case of rename whiteout, we
fall back to full commits.

Amir mentioned that instead of creating a new whiteout object for
every rename, we can create a static whiteout object with irrelevant
nlink. That will make fast commits to not fall back to full
commit. But until this happens, this patch will ensure correctness by
falling back to full commits.

Fixes: 8016e29f4362 ("ext4: fast commit recovery path")
Cc: stable@kernel.org
Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20210316221921.1124955-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2021-02-25T18:06:55+00:00

Pull ext4 updates from Ted Ts'o:
 "Miscellaneous ext4 cleanups and bug fixes. Pretty boring this cycle..."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: add .kunitconfig fragment to enable ext4-specific tests
  ext: EXT4_KUNIT_TESTS should depend on EXT4_FS instead of selecting it
  ext4: reset retry counter when ext4_alloc_file_blocks() makes progress
  ext4: fix potential htree index checksum corruption
  ext4: factor out htree rep invariant check
  ext4: Change list_for_each* to list_for_each_entry*
  ext4: don't try to processed freed blocks until mballoc is initialized
  ext4: use DEFINE_MUTEX() for mutex lock

ext4: Change list_for_each* to list_for_each_entry*

2021-02-03T05:05:01+00:00

In the fast_commit.c, list_for_each* + list_entry can be changed to
list_for_each_entry*. It reduces number of variables and lines.

Signed-off-by: Daejun Park 
Link: https://lore.kernel.org/r/20210111013726epcms2p4579ae56040d7043db785bf0d0a785dc7@epcms2p4
Signed-off-by: Theodore Ts'o

block: use an on-stack bio in blkdev_issue_flush

2021-01-27T16:51:48+00:00

There is no point in allocating memory for a synchronous flush.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Chaitanya Kulkarni 
Acked-by: Damien Le Moal 
Signed-off-by: Jens Axboe

ext4: remove expensive flush on fast commit

2021-01-15T19:41:31+00:00

In the fast commit, it adds REQ_FUA and REQ_PREFLUSH on each fast
commit block when barrier is enabled.  However, in recovery phase,
ext4 compares CRC value in the tail.  So it is sufficient to add
REQ_FUA and REQ_PREFLUSH on the block that has tail.

Signed-off-by: Daejun Park 
Reviewed-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20210106013242epcms2p5b6b4ed8ca86f29456fdf56aa580e74b4@epcms2p5
Signed-off-by: Theodore Ts'o

ext4: fix wrong list_splice in ext4_fc_cleanup

2021-01-15T19:40:12+00:00

After full/fast commit, entries in staging queue are promoted to main
queue. In ext4_fs_cleanup function, it splice to staging queue to
staging queue.

Fixes: aa75f4d3daaeb ("ext4: main fast-commit commit path")
Signed-off-by: Daejun Park 
Reviewed-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201230094851epcms2p6eeead8cc984379b37b2efd21af90fd1a@epcms2p6
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org

ext4: use IS_ERR instead of IS_ERR_OR_NULL and set inode null when IS_ERR

2021-01-15T19:39:14+00:00

1: ext4_iget/ext4_find_extent never returns NULL, use IS_ERR
instead of IS_ERR_OR_NULL to fix this.

2: ext4_fc_replay_inode should set the inode to NULL when IS_ERR.
and go to call iput properly.

Fixes: 8016e29f4362 ("ext4: fast commit recovery path")
Signed-off-by: Yi Li 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20201230033827.3996064-1-yili@winhong.com
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org

ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h

2020-12-17T18:30:45+00:00

This patch makes fast_commit.h byte by byte identical with
e2fsprogs/fast_commit.h. This will help us ensure that there are no
on-disk format inconsistencies between e2fsck and kernel ext4.

Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201120202232.2240293-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

ext4: add docs about fast commit idempotence

2020-12-17T18:30:44+00:00

Fast commit on-disk format is designed such that the replay of these
tags can be idempotent. This patch adds documentation in the code in
form of comments and in form kernel docs that describes these
characteristics. This patch also adds a TODO item needed to ensure
kernel fast commit replay idempotence.

Signed-off-by: Harshad Shirwadkar 
Link: https://lore.kernel.org/r/20201119232822.1860882-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o

ext4: fix sparse warnings in fast_commit code

2020-11-07T05:08:23+00:00

Add missing __acquire() and __releases() annotations, and make
fc_ineligible_reasons[] static, as it is not used outside of
fs/ext4/fast_commit.c.

Signed-off-by: Theodore Ts'o