static void put_extra_state(QEMUFile *f, void *pv, size_t size)
{
    VirtIODevice *vdev = pv;
    BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);

    k->save_extra_state(qbus->parent, f);
}

static void put_extra_state(QEMUFile *f, void *pv, size_t size)
{
    VirtIODevice *vdev = pv;
    BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);

    k->save_extra_state(qbus->parent, f);
}
