diff options
| author | Brian Foster <bfoster@redhat.com> | 2014-09-23 05:37:09 (GMT) |
|---|---|---|
| committer | Dave Chinner <david@fromorbit.com> | 2014-09-23 05:37:09 (GMT) |
| commit | 2c845f5a5f238f42376b6551a7f7716952c8f509 (patch) | |
| tree | 95ccf2c9594429f5bf3791b3124b7e14682d99f7 /fs/xfs/libxfs/xfs_bmap.h | |
| parent | 0d085a529b427d97710e6a41f8a4f23e1757cd12 (diff) | |
| download | linux-2c845f5a5f238f42376b6551a7f7716952c8f509.tar.xz | |
xfs: track collapse via file offset rather than extent index
The collapse range implementation uses a transaction per extent shift.
The progress of the overall operation is tracked via the current extent
index of the in-core extent list. This is racy because the ilock must be
dropped and reacquired for each transaction according to locking and log
reservation rules. Therefore, writeback to prior regions of the file is
possible and can change the extent count. This changes the extent to
which the current index refers and causes the collapse to fail mid
operation. To avoid this problem, the entire file is currently written
back before the collapse operation starts.
To eliminate the need to flush the entire file, use the file offset
(fsb) to track the progress of the overall extent shift operation rather
than the extent index. Modify xfs_bmap_shift_extents() to
unconditionally convert the start_fsb parameter to an extent index and
return the file offset of the extent where the shift left off, if
further extents exist. The bulk of ths function can remain based on
extent index as ilock is held by the caller. xfs_collapse_file_space()
now uses the fsb output as the starting point for the subsequent shift.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs/libxfs/xfs_bmap.h')
| -rw-r--r-- | fs/xfs/libxfs/xfs_bmap.h | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h index b879ca5..44db6db 100644 --- a/fs/xfs/libxfs/xfs_bmap.h +++ b/fs/xfs/libxfs/xfs_bmap.h @@ -178,9 +178,8 @@ int xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx, xfs_extnum_t num); uint xfs_default_attroffset(struct xfs_inode *ip); int xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip, - int *done, xfs_fileoff_t start_fsb, - xfs_fileoff_t offset_shift_fsb, xfs_extnum_t *current_ext, - xfs_fsblock_t *firstblock, struct xfs_bmap_free *flist, - int num_exts); + xfs_fileoff_t start_fsb, xfs_fileoff_t offset_shift_fsb, + int *done, xfs_fileoff_t *next_fsb, xfs_fsblock_t *firstblock, + struct xfs_bmap_free *flist, int num_exts); #endif /* __XFS_BMAP_H__ */ |