# Re: \[PATCH V4 7/7\] vDPA/ifcvf: deduce VIRTIO device ID from pdev ids

- From: Jason Wang \<hidden\>
- Date: 2021-03-17 04:09:02 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/03/6304404
- Thread: https://ratatoskr.run/netdev/2021/03/6300136/t.md

```text

在 2021/3/15 下午3:45, Zhu Lingshan 写道:
>   static u32 ifcvf_vdpa_get_device_id(struct vdpa_device *vdpa_dev)
>   {
> -	return VIRTIO_ID_NET;
> +	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
> +	u32 ret = -EOPNOTSUPP;
> +
> +	if (ifcvf_probed_virtio_net(vf))
> +		ret = VIRTIO_ID_NET;


So the point is to simplify the future extension.

How about simply?

if (device_id>0x1040)
    return devce_id - 0x1040;
else
    return device_id;

Since I don't think you plan to introduce device whose vendor id is not 1AF4 and the subsys vendor/device id is not interesting to vDPA bus.

Thanks


> +
> +	return ret;
>   }

```