1 files changed, 3 insertions, 1 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 0910cb75b65d..4f443703065e 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -864,6 +864,7 @@ xfs_alloc_file_space(
         xfs_filblks_t           allocatesize_fsb;
         xfs_extlen_t            extsz, temp;
         xfs_fileoff_t           startoffset_fsb;
+        xfs_fileoff_t           endoffset_fsb;
         int                     nimaps;
         int                     quota_flag;
         int                     rt;
@@ -891,7 +892,8 @@ xfs_alloc_file_space(
         imapp = &imaps[0];
         nimaps = 1;
         startoffset_fsb = XFS_B_TO_FSBT(mp, offset);
-        allocatesize_fsb = XFS_B_TO_FSB(mp, count);
+        endoffset_fsb = XFS_B_TO_FSB(mp, offset + count);
+        allocatesize_fsb = endoffset_fsb - startoffset_fsb;
 
         /*
          * Allocate file space until done or until there is an error