[PATCH v2 00/12] lazytime fix and cleanups

[Eric Biggers <ebiggers@kernel.org>]

Hello,

Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
expirations.  I originally reported this last year
(https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
the bug causes inodes to remain dirty after a sync.

It also turns out that lazytime on XFS is partially broken because it
doesn't actually write timestamps to disk after a sync() or after
dirtytime_expire_interval.  This is fixed by the same fix.

This supersedes previously proposed fixes, including
https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
year (which had some issues and didn't fix the XFS bug), and v1 of this
patchset which took a different approach
(https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).

Patches 2-12 then clean up various things related to lazytime and
writeback, such as clarifying the semantics of ->dirty_inode() and the
inode dirty flags, and improving comments.  Most of these patches could
be applied independently if needed.

This patchset applies to v5.11-rc2.

Changed since v1:
  - Switched to the fix suggested by Jan Kara, and dropped the
    patches which introduced ->lazytime_expired().
  - Fixed bugs in the fat and ext4 patches.
  - Added patch "fs: improve comments for writeback_single_inode()".
  - Reordered the patches a bit.
  - Added Reviewed-by's.

Eric Biggers (12):
  fs: fix lazytime expiration handling in __writeback_single_inode()
  fs: correctly document the inode dirty flags
  fs: only specify I_DIRTY_TIME when needed in generic_update_time()
  fat: only specify I_DIRTY_TIME when needed in fat_update_time()
  fs: don't call ->dirty_inode for lazytime timestamp updates
  fs: pass only I_DIRTY_INODE flags to ->dirty_inode
  fs: clean up __mark_inode_dirty() a bit
  fs: drop redundant check from __writeback_single_inode()
  fs: improve comments for writeback_single_inode()
  gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
  ext4: simplify i_state checks in __ext4_update_other_inode_time()
  xfs: remove a stale comment from xfs_file_aio_write_checks()

 Documentation/filesystems/vfs.rst |   5 +-
 fs/ext4/inode.c                   |  20 +----
 fs/f2fs/super.c                   |   3 -
 fs/fat/misc.c                     |  23 +++---
 fs/fs-writeback.c                 | 132 +++++++++++++++++-------------
 fs/gfs2/file.c                    |   4 +-
 fs/gfs2/super.c                   |   2 -
 fs/inode.c                        |  38 +++++----
 fs/xfs/xfs_file.c                 |   6 --
 include/linux/fs.h                |  18 ++--
 10 files changed, 132 insertions(+), 119 deletions(-)


base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
-- 
2.30.0