Patchwork [Kernel,BUG] ext4 for v2.6.32 round II

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Submitter Theodore Tso
Date Oct. 1, 2009, 3:01 a.m.
Message ID <20091001030151.GR24383@mit.edu>
Download mbox | patch
Permalink /patch/50810/
State New, archived
Headers show

Comments

Patch

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index ec367bc..6e65d0e 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1146,8 +1146,8 @@  static int check_block_validity(struct inode *inode, const char *msg,
 }
 
 /*
- * Return the number of dirty pages in the given inode starting at
- * page frame idx.
+ * Return the number of contiguous dirty pages in a given inode
+ * starting at page frame idx.
  */
 static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
 				    unsigned int max_pages)
@@ -1181,15 +1181,15 @@  static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
 				unlock_page(page);
 				break;
 			}
-			head = page_buffers(page);
-			bh = head;
-			do {
-				if (!buffer_delay(bh) &&
-				    !buffer_unwritten(bh)) {
-					done = 1;
-					break;
-				}
-			} while ((bh = bh->b_this_page) != head);
+			if (page_has_buffers(page)) {
+				bh = head = page_buffers(page);
+				do {
+					if (!buffer_delay(bh) &&
+					    !buffer_unwritten(bh))
+						done = 1;
+					bh = bh->b_this_page;
+				} while (!done && (bh != head));
+			}
 			unlock_page(page);
 			if (done)
 				break;