1 files changed, 2 insertions, 0 deletions

diff --git a/fs/xfs/xfs_bmap_btree.h b/fs/xfs/xfs_bmap_btree.h
index 70c43d9f72c1..1b726d626941 100644
--- a/fs/xfs/xfs_bmap_btree.h
+++ b/fs/xfs/xfs_bmap_btree.h
@@ -196,6 +196,8 @@ typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
 #define XFS_BMDR_SPACE_CALC(nrecs) \
         (int)(sizeof(xfs_bmdr_block_t) + \
                ((nrecs) * (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t))))
+#define XFS_BMAP_BMDR_SPACE(bb) \
+        (XFS_BMDR_SPACE_CALC(be16_to_cpu((bb)->bb_numrecs)))
 
 /*
  * Maximum number of bmap btree levels.