diff options
author | Dave Chinner <dchinner@redhat.com> | 2019-10-17 22:12:01 +0200 |
---|---|---|
committer | Darrick J. Wong <darrick.wong@oracle.com> | 2019-10-17 22:12:01 +0200 |
commit | 7684e2c4384d5d1f884b01ab8bff2369e4db0bff (patch) | |
tree | 38603082924ece0934d128b7ed08be6a39fa3d23 /fs/xfs/xfs_iomap.c | |
parent | xfs: Use iomap_dio_rw to wait for unaligned direct IO (diff) | |
download | linux-7684e2c4384d5d1f884b01ab8bff2369e4db0bff.tar.xz linux-7684e2c4384d5d1f884b01ab8bff2369e4db0bff.zip |
iomap: iomap that extends beyond EOF should be marked dirty
When doing a direct IO that spans the current EOF, and there are
written blocks beyond EOF that extend beyond the current write, the
only metadata update that needs to be done is a file size extension.
However, we don't mark such iomaps as IOMAP_F_DIRTY to indicate that
there is IO completion metadata updates required, and hence we may
fail to correctly sync file size extensions made in IO completion
when O_DSYNC writes are being used and the hardware supports FUA.
Hence when setting IOMAP_F_DIRTY, we need to also take into account
whether the iomap spans the current EOF. If it does, then we need to
mark it dirty so that IO completion will call generic_write_sync()
to flush the inode size update to stable storage correctly.
Fixes: 3460cac1ca76 ("iomap: Use FUA for pure data O_DSYNC DIO writes")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: removed the ext4 part; they'll handle it separately]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Diffstat (limited to 'fs/xfs/xfs_iomap.c')
-rw-r--r-- | fs/xfs/xfs_iomap.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index f780e223b118..32993c2acbd9 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1049,6 +1049,13 @@ xfs_file_iomap_begin( trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap); out_finish: + /* + * Writes that span EOF might trigger an IO size update on completion, + * so consider them to be dirty for the purposes of O_DSYNC even if + * there is no other metadata changes pending or have been made here. + */ + if ((flags & IOMAP_WRITE) && offset + length > i_size_read(inode)) + iomap->flags |= IOMAP_F_DIRTY; return xfs_bmbt_to_iomap(ip, iomap, &imap, shared); out_found: |