btrfs: do not write corrupted metadata blocks to disk

[linux-2.6-block.git] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 9cafae5c20615bcc16f9c6c992b237bc4de74f0e..8579b35bb16029c19cb0c3e19e0d836e6ba53805 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -512,9 +512,20 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
        eb = (struct extent_buffer *)page->private;
        if (page != eb->pages[0])
                return 0;
+
        found_start = btrfs_header_bytenr(eb);
-       if (WARN_ON(found_start != start || !PageUptodate(page)))
-               return 0;
+       /*
+        * Please do not consolidate these warnings into a single if.
+        * It is useful to know what went wrong.
+        */
+       if (WARN_ON(found_start != start))
+               return -EUCLEAN;
+       if (WARN_ON(!PageUptodate(page)))
+               return -EUCLEAN;
+
+       ASSERT(memcmp_extent_buffer(eb, fs_info->fsid,
+                       btrfs_header_fsid(), BTRFS_FSID_SIZE) == 0);
+
        return csum_tree_block(fs_info, eb, 0);
 }