Re: [RFC PATCH 1/2] vfio-mdev: Wire in a request handler for mdev parent

Tony Krowiak
2020-11-23T19:12:55Z

On 11/19/20 10:56 AM, Halil Pasic wrote:
> On Thu, 19 Nov 2020 12:30:26 +0100
> Cornelia Huck <cohuck@redhat.com> wrote:
>
>>> +static void vfio_mdev_request(void *device_data, unsigned int count)
>>> +{
>>> + struct mdev_device *mdev = device_data;
>>> + struct mdev_parent *parent = mdev->parent;
>>> +
>>> + if (unlikely(!parent->ops->request))
>> Hm. Do you think that all drivers should implement a ->request()
>> callback?
> @Tony: What do you think, does vfio_ap need something like this?
>
> BTW how is this supposed to work in a setup where the one parent
> has may children (like vfio_ap or the gpu slice and dice usecases).
>
> After giving this some thought I'm under the impression, I don't
> get the full picture yet.

Eric Farman touched base with me on Friday to discuss this, but
I was on my way out the door for an appointment. He is off this
week; so, the bottom line for me is that I don't have even a
piece of the picture here and therefore don't have enough
info to speculate on whether vfio_ap needs something like this.

>
> Regards,
> Halil