[Spice-devel] [PATCH v3 2/2] virtio-video: Define a feature for exported objects from different virtio devices

[Keiichi Watanabe]

Hi,

On Tue, Feb 25, 2020 at 7:01 PM Gerd Hoffmann <kraxel at redhat.com> wrote:
>
>   Hi,
>
> > +        /*
> > +         * Followed by either
> > +         * - struct virtio_video_mem_entry entries[]
> > +         *   for VIRTIO_VIDEO_MEM_TYPE_GUEST_PAGES
> > +         * - struct virtio_video_object_entry entries[]
> > +         *   for VIRTIO_VIDEO_MEM_TYPE_VIRTIO_OBJECT
>
> Wouldn't that be a single virtio_video_object_entry?
> Or could it be one per plane?

It depends on the value of "planes_layout" in virtio_video_resource_create.
I have documented this restriction as follows:

> +If \field{planes_layout} is VIRTIO_VIDEO_PLANES_LAYOUT_SINGLE_BUFFER,
> +the number of \field{virtio_video_object_entry} MUST be one. If it is
> +VIRTIO_VIDEO_PLANES_LAYOUT_PER_PLANE, the number MUST be equal to
> +\field{num_planes}.

Best regards,
Keiichi


>
> cheers,
>   Gerd
>