Btrfs: Write out all super blocks on commit, and bring back proper barrier support

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

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 3d5d0a9cb827..89548837a1cc 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -21,9 +21,12 @@
 
 #include <linux/bio.h>
 
+struct buffer_head;
 struct btrfs_device {
         struct list_head dev_list;
         struct btrfs_root *dev_root;
+        struct buffer_head *pending_io;
+        int barriers;
         spinlock_t io_lock;
 
         struct block_device *bdev;