Btrfs: Fix PAGE_CACHE_SHIFT shifts on 32 bit machines

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 843e920388e..abdd9caad94 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -301,7 +301,8 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
                         SetPageUptodate(p);
                         set_page_dirty(p);
                 }
-                last_end = pages[num_pages -1]->index << PAGE_CACHE_SHIFT;
+                last_end = (u64)(pages[num_pages -1]->index) <<
+                                PAGE_CACHE_SHIFT;
                 last_end += PAGE_CACHE_SIZE - 1;
                 set_extent_delalloc(em_tree, start_pos, end_of_last_block,
                                  GFP_NOFS);