diff --git a/mm/truncate.c b/mm/truncate.c
index 29c18f6..9173ab5 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -282,8 +282,8 @@
 					 * Zap the rest of the file in one hit.
 					 */
 					unmap_mapping_range(mapping,
-					    page_index << PAGE_CACHE_SHIFT,
-					    (end - page_index + 1)
+					   (loff_t)page_index<<PAGE_CACHE_SHIFT,
+					   (loff_t)(end - page_index + 1)
 							<< PAGE_CACHE_SHIFT,
 					    0);
 					did_range_unmap = 1;
@@ -292,7 +292,7 @@
 					 * Just zap this page
 					 */
 					unmap_mapping_range(mapping,
-					  page_index << PAGE_CACHE_SHIFT,
+					  (loff_t)page_index<<PAGE_CACHE_SHIFT,
 					  PAGE_CACHE_SIZE, 0);
 				}
 			}