1 files changed, 35 insertions, 3 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index cd9a5400ba4f..e9db7fc95b70 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1459,7 +1459,19 @@ xfs_shift_file_space(
                 return error;
 
         /*
-         * The extent shiting code works on extent granularity. So, if
+         * Clean out anything hanging around in the cow fork now that
+         * we've flushed all the dirty data out to disk to avoid having
+         * CoW extents at the wrong offsets.
+         */
+        if (xfs_is_reflink_inode(ip)) {
+                error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF,
+                                true);
+                if (error)
+                        return error;
+        }
+
+        /*
+         * The extent shifting code works on extent granularity. So, if
          * stop_fsb is not the starting block of extent, we need to split
          * the extent at stop_fsb.
          */
@@ -2110,11 +2122,31 @@ xfs_swap_extents(
                 ip->i_d.di_flags2 |= tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
                 tip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
                 tip->i_d.di_flags2 |= f & XFS_DIFLAG2_REFLINK;
+        }
+
+        /* Swap the cow forks. */
+        if (xfs_sb_version_hasreflink(&mp->m_sb)) {
+                xfs_extnum_t    extnum;
+
+                ASSERT(ip->i_cformat == XFS_DINODE_FMT_EXTENTS);
+                ASSERT(tip->i_cformat == XFS_DINODE_FMT_EXTENTS);
+
+                extnum = ip->i_cnextents;
+                ip->i_cnextents = tip->i_cnextents;
+                tip->i_cnextents = extnum;
+
                 cowfp = ip->i_cowfp;
                 ip->i_cowfp = tip->i_cowfp;
                 tip->i_cowfp = cowfp;
-                xfs_inode_set_cowblocks_tag(ip);
-                xfs_inode_set_cowblocks_tag(tip);
+
+                if (ip->i_cowfp && ip->i_cnextents)
+                        xfs_inode_set_cowblocks_tag(ip);
+                else
+                        xfs_inode_clear_cowblocks_tag(ip);
+                if (tip->i_cowfp && tip->i_cnextents)
+                        xfs_inode_set_cowblocks_tag(tip);
+                else
+                        xfs_inode_clear_cowblocks_tag(tip);
         }
 
         xfs_trans_log_inode(tp, ip,  src_log_flags);