diff options
| author | Darrick J. Wong <darrick.wong@oracle.com> | 2016-10-03 09:11:36 -0700 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2016-10-05 16:26:04 -0700 |
| commit | db1327b16c2b24e28d1e5899bced89db9ae6538e (patch) | |
| tree | 26387f590ce880b409245a80c40dabe47a7dc6e5 /fs/xfs/xfs_iomap.c | |
| parent | 43caeb187deb92b3cc343fce9c2310512f6ac9cd (diff) | |
xfs: report shared extent mappings to userspace correctly
Report shared extents through the iomap interface so that FIEMAP flags
shared blocks accurately. Have xfs_vm_bmap return zero for reflinked
files because the bmap-based swap code requires static block mappings,
which is incompatible with copy on write.
NOTE: Existing userspace bmap users such as lilo will have the same
problem with reflink files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index ad6939df9680..765849ed9b70 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -961,6 +961,7 @@ xfs_file_iomap_begin( struct xfs_mount *mp = ip->i_mount; struct xfs_bmbt_irec imap; xfs_fileoff_t offset_fsb, end_fsb; + bool shared, trimmed; int nimaps = 1, error = 0; unsigned lockmode; @@ -989,7 +990,14 @@ xfs_file_iomap_begin( end_fsb = XFS_B_TO_FSB(mp, offset + length); error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, - &nimaps, XFS_BMAPI_ENTIRE); + &nimaps, 0); + if (error) { + xfs_iunlock(ip, lockmode); + return error; + } + + /* Trim the mapping to the nearest shared extent boundary. */ + error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed); if (error) { xfs_iunlock(ip, lockmode); return error; @@ -1028,6 +1036,8 @@ xfs_file_iomap_begin( } xfs_bmbt_to_iomap(ip, iomap, &imap); + if (shared) + iomap->flags |= IOMAP_F_SHARED; return 0; } |