xfs: Fix xfs_prepare_shift() range for RT

The RT extent range must be considered in the xfs_flush_unmap_range() call
to stabilize the boundary.

This code change is originally from Dave Chinner.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 501068eab502153fb5b9a6aa9baf599e318fbf11..fe2e2c930975501b447ca5b36109de998275dd3f 100644 (file)
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -902,7 +902,7 @@ xfs_prepare_shift(
        struct xfs_inode        *ip,
        loff_t                  offset)
 {
-       struct xfs_mount        *mp = ip->i_mount;
+       unsigned int            rounding;
        int                     error;
 
        /*
@@ -920,11 +920,13 @@ xfs_prepare_shift(
         * with the full range of the operation. If we don't, a COW writeback
         * completion could race with an insert, front merge with the start
         * extent (after split) during the shift and corrupt the file. Start
-        * with the block just prior to the start to stabilize the boundary.
+        * with the allocation unit just prior to the start to stabilize the
+        * boundary.
         */
-       offset = round_down(offset, mp->m_sb.sb_blocksize);
+       rounding = xfs_inode_alloc_unitsize(ip);
+       offset = rounddown_64(offset, rounding);
        if (offset)
-               offset -= mp->m_sb.sb_blocksize;
+               offset -= rounding;
 
        /*
         * Writeback and invalidate cache for the remainder of the file as we're