- Minor cleanups of the sb_start_* fs freeze helpers.
-----BEGIN PGP SIGNATURE-----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=ZC9a
-----END PGP SIGNATURE-----
Merge tag 'vfs-5.10-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull fs freeze fix and cleanups from Darrick Wong:
"A single vfs fix for 5.10, along with two subsequent cleanups.
A very long time ago, a hack was added to the vfs fs freeze protection
code to work around lockdep complaints about XFS, which would try to
run a transaction (which requires intwrite protection) to finalize an
xfs freeze (by which time the vfs had already taken intwrite).
Fast forward a few years, and XFS fixed the recursive intwrite problem
on its own, and the hack became unnecessary. Fast forward almost a
decade, and latent bugs in the code converting this hack from freeze
flags to freeze locks combine with lockdep bugs to make this reproduce
frequently enough to notice page faults racing with freeze.
Since the hack is unnecessary and causes thread race errors, just get
rid of it completely. Making this kind of vfs change midway through a
cycle makes me nervous, but a large enough number of the usual
VFS/ext4/XFS/btrfs suspects have said this looks good and solves a
real problem vector.
And once that removal is done, __sb_start_write is now simple enough
that it becomes possible to refactor the function into smaller,
simpler static inline helpers in linux/fs.h. The cleanup is
straightforward.
Summary:
- Finally remove the "convert to trylock" weirdness in the fs freezer
code. It was necessary 10 years ago to deal with nested
transactions in XFS, but we've long since removed that; and now
this is causing subtle race conditions when lockdep goes offline
and sb_start_* aren't prepared to retry a trylock failure.
- Minor cleanups of the sb_start_* fs freeze helpers"
* tag 'vfs-5.10-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: move __sb_{start,end}_write* to fs.h
vfs: separate __sb_start_write into blocking and non-blocking helpers
vfs: remove lockdep bogosity in __sb_start_write
f01c30de86