1 files changed, 13 insertions, 0 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 2f1e30d39a35..76b6a2910e40 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1470,6 +1470,19 @@ xfs_collapse_file_space(
         start_fsb = XFS_B_TO_FSB(mp, offset + len);
         shift_fsb = XFS_B_TO_FSB(mp, len);
 
+        /*
+         * writeback the entire file to prevent concurrent writeback of ranges
+         * outside the collapsing region from changing the extent list.
+         *
+         * XXX: This is a temporary fix until the extent shift loop below is
+         * converted to use offsets and lookups within the ILOCK rather than
+         * carrying around the index into the extent list for the next
+         * iteration.
+         */
+        error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
+        if (error)
+                return error;
+
         error = xfs_free_file_space(ip, offset, len);
         if (error)
                 return error;