btrfs: Handle btrfs_set_extent_delalloc failure in fixup worker

This function was introduced by 247e743cbe6e ("Btrfs: Use async helpers
to deal with pages that have been improperly dirtied") and it didn't do
any error handling then. This function might very well fail in ENOMEM
situation, yet it's not handled, this could lead to inconsistent state.
So let's handle the failure by setting the mapping error bit.

Cc: stable@vger.kernel.org
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 034d7333b14dda57829f642c9923e31d7d95faa7..9ad8c9321c8f6eb2f2f26692676d187148f09597 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2116,8 +2116,15 @@ again:
                goto out;
         }
 
-       btrfs_set_extent_delalloc(inode, page_start, page_end, 0, &cached_state,
-                                 0);
+       ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0,
+                                       &cached_state, 0);
+       if (ret) {
+               mapping_set_error(page->mapping, ret);
+               end_extent_writepage(page, ret, page_start, page_end);
+               ClearPageChecked(page);
+               goto out;
+       }
+
        ClearPageChecked(page);
        set_page_dirty(page);
        btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);