diff options
| author | Jan Kara <jack@suse.cz> | 2025-07-30 12:28:41 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-28 16:34:25 +0200 |
| commit | 86de3aaf29a4d7273aa1767268e9dfda69cc6917 (patch) | |
| tree | 27d801b560acc59865c557842d13955ab53fccbc | |
| parent | 13344509b72df686cf8592b0d45aca11a91bb690 (diff) | |
iomap: Fix broken data integrity guarantees for O_SYNC writes
commit 6b65028e2b51c023a816eabffea88980fdd5564e upstream.
Commit d279c80e0bac ("iomap: inline iomap_dio_bio_opflags()") has broken
the logic in iomap_dio_bio_iter() in a way that when the device does
support FUA (or has no writeback cache) and the direct IO happens to
freshly allocated or unwritten extents, we will *not* issue fsync after
completing direct IO O_SYNC / O_DSYNC write because the
IOMAP_DIO_WRITE_THROUGH flag stays mistakenly set. Fix the problem by
clearing IOMAP_DIO_WRITE_THROUGH whenever we do not perform FUA write as
it was originally intended.
CC: John Garry <john.g.garry@oracle.com>
CC: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Fixes: d279c80e0bac ("iomap: inline iomap_dio_bio_opflags()")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/20250730102840.20470-2-jack@suse.cz
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/iomap/direct-io.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 844261a31156..b875165b7c27 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -368,14 +368,14 @@ static int iomap_dio_bio_iter(struct iomap_iter *iter, struct iomap_dio *dio) if (iomap->flags & IOMAP_F_SHARED) dio->flags |= IOMAP_DIO_COW; - if (iomap->flags & IOMAP_F_NEW) { + if (iomap->flags & IOMAP_F_NEW) need_zeroout = true; - } else if (iomap->type == IOMAP_MAPPED) { - if (iomap_dio_can_use_fua(iomap, dio)) - bio_opf |= REQ_FUA; - else - dio->flags &= ~IOMAP_DIO_WRITE_THROUGH; - } + else if (iomap->type == IOMAP_MAPPED && + iomap_dio_can_use_fua(iomap, dio)) + bio_opf |= REQ_FUA; + + if (!(bio_opf & REQ_FUA)) + dio->flags &= ~IOMAP_DIO_WRITE_THROUGH; /* * We can only do deferred completion for pure overwrites that |