uint16_t (*set_config_irq)(struct virtio_hw *hw, uint16_t vec);
uint16_t (*get_queue_num)(struct virtio_hw *hw, uint16_t queue_id);
uint16_t (*set_config_irq)(struct virtio_hw *hw, uint16_t vec);
uint16_t (*get_queue_num)(struct virtio_hw *hw, uint16_t queue_id);