Btrfs: introduce per-subvolume ordered extent list

The reason we introduce per-subvolume ordered extent list is the same
as the per-subvolume delalloc inode list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index f6e1b54..aa559f1 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4164,7 +4164,7 @@
 		err = ret;
 		goto out;
 	}
-	btrfs_wait_ordered_extents(fs_info->tree_root, 0);
+	btrfs_wait_all_ordered_extents(fs_info, 0);
 
 	while (1) {
 		mutex_lock(&fs_info->cleaner_mutex);