Btrfs: Btree defrag on the extent-mapping tree as well

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2e797d5..74f3de4 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -121,7 +121,9 @@
 		filemap_flush(root->fs_info->btree_inode->i_mapping);
 		return 0;
 	}
+	btrfs_clean_old_snapshots(root);
 	mutex_lock(&root->fs_info->fs_mutex);
+	btrfs_defrag_dirty_roots(root->fs_info);
 	trans = btrfs_start_transaction(root, 1);
 	ret = btrfs_commit_transaction(trans, root);
 	sb->s_dirt = 0;