func: static int virtio_blk_device_exit(DeviceState *dev)
  
  {
  
      VirtIODevice *vdev = VIRTIO_DEVICE(dev);
  
      VirtIOBlock *s = VIRTIO_BLK(dev);
  
  #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
  
      remove_migration_state_change_notifier(&s->migration_state_notifier);
  
      virtio_blk_data_plane_destroy(s->dataplane);
  
      s->dataplane = NULL;
  
  #endif
  
      qemu_del_vm_change_state_handler(s->change);
  
      unregister_savevm(dev, "virtio-blk", s);
  
      blockdev_mark_auto_del(s->bs);
  
      virtio_cleanup(vdev);
  
      return 0;
  
  }
  