1 files changed, 8 insertions, 0 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index 578eceafba4a..b2a35ebf071a 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -674,8 +674,16 @@ done2:
                  * generic_delete_inode did it, before we lowered next_index.
                  * Also, though shmem_getpage checks i_size before adding to
                  * cache, no recheck after: so fix the narrow window there too.
+                 *
+                 * Recalling truncate_inode_pages_range and unmap_mapping_range
+                 * every time for punch_hole (which never got a chance to clear
+                 * SHMEM_PAGEIN at the start of vmtruncate_range) is expensive,
+                 * yet hardly ever necessary: try to optimize them out later.
                  */
                 truncate_inode_pages_range(inode->i_mapping, start, end);
+                if (punch_hole)
+                        unmap_mapping_range(inode->i_mapping, start,
+                                                        end - start, 1);
         }
 
         spin_lock(&info->lock);