diff options
| author | Darrick J. Wong <djwong@kernel.org> | 2023-05-02 02:14:51 +0300 |
|---|---|---|
| committer | Dave Chinner <dchinner@redhat.com> | 2023-05-02 02:14:51 +0300 |
| commit | 1f1397b7218d7f8e53e33c6b58cbf9601cd2d8e6 (patch) | |
| tree | ba31b944b970f221adae3cc8f530af1eebd3d364 /fs/xfs | |
| parent | 397b2d7e0f3e28bbeaa05cf8e10d0fd601f446f4 (diff) | |
| download | linux-1f1397b7218d7f8e53e33c6b58cbf9601cd2d8e6.tar.xz | |
xfs: don't allocate into the data fork for an unshare request
For an unshare request, we only have to take action if the data fork has
a shared mapping. We don't care if someone else set up a cow operation.
If we find nothing in the data fork, return a hole to avoid allocating
space.
Note that fallocate will replace the delalloc reservation with an
unwritten extent anyway, so this has no user-visible effects outside of
avoiding unnecessary updates.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs')
| -rw-r--r-- | fs/xfs/xfs_iomap.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 285885c308bd..18c8f168b153 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1006,8 +1006,9 @@ xfs_buffered_write_iomap_begin( if (eof) imap.br_startoff = end_fsb; /* fake hole until the end */ - /* We never need to allocate blocks for zeroing a hole. */ - if ((flags & IOMAP_ZERO) && imap.br_startoff > offset_fsb) { + /* We never need to allocate blocks for zeroing or unsharing a hole. */ + if ((flags & (IOMAP_UNSHARE | IOMAP_ZERO)) && + imap.br_startoff > offset_fsb) { xfs_hole_to_iomap(ip, iomap, offset_fsb, imap.br_startoff); goto out_unlock; } |