static int qcow2_setup_backing_file(struct bdev *bdev, struct qcow2_header *header)
{
	/* backing file info is at the same place in both headers,
	 * so we can cheat and use this for qcow2 also */
	return qcow_setup_backing_file(bdev, (struct qcow_header *) header);
}
static int qcow2_setup_backing_file(struct bdev *bdev, struct qcow2_header *header)
{
	 
	return qcow_setup_backing_file(bdev, (struct qcow_header *) header);
}