1 files changed, 13 insertions, 5 deletions

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index c8f9bd308821..4a09ff169870 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1435,6 +1435,10 @@ static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
         return 0;
 }
 
+static int buffer_unmapped(handle_t *handle, struct buffer_head *bh)
+{
+        return !buffer_mapped(bh);
+}
 /*
  * Note that we always start a transaction even if we're not journalling
  * data.  This is to preserve ordering: any hole instantiation within
@@ -1505,6 +1509,15 @@ static int ext3_ordered_writepage(struct page *page,
         if (ext3_journal_current_handle())
                 goto out_fail;
 
+        if (!page_has_buffers(page)) {
+                create_empty_buffers(page, inode->i_sb->s_blocksize,
+                                (1 << BH_Dirty)|(1 << BH_Uptodate));
+        } else if (!walk_page_buffers(NULL, page_buffers(page), 0, PAGE_CACHE_SIZE, NULL, buffer_unmapped)) {
+                /* Provide NULL instead of get_block so that we catch bugs if buffers weren't really mapped */
+                return block_write_full_page(page, NULL, wbc);
+        }
+        page_bufs = page_buffers(page);
+
         handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode));
 
         if (IS_ERR(handle)) {
@@ -1512,11 +1525,6 @@ static int ext3_ordered_writepage(struct page *page,
                 goto out_fail;
         }
 
-        if (!page_has_buffers(page)) {
-                create_empty_buffers(page, inode->i_sb->s_blocksize,
-                                (1 << BH_Dirty)|(1 << BH_Uptodate));
-        }
-        page_bufs = page_buffers(page);
         walk_page_buffers(handle, page_bufs, 0,
                         PAGE_CACHE_SIZE, NULL, bget_one);