[PATCH RFC 3/3] drm/virtio: Include modifier as part of set_scanout_blob

[Gerd Hoffmann]

> --- a/include/uapi/linux/virtio_gpu.h
> +++ b/include/uapi/linux/virtio_gpu.h
> @@ -420,6 +420,7 @@ struct virtio_gpu_set_scanout_blob {
>  	__le32 padding;
>  	__le32 strides[4];
>  	__le32 offsets[4];
> +	__le64 modifier;
>  };

All protocol changes (uapi/linux/virtio_gpu.h updates) should go to a
separate patch (best first in the series).  A feature flag is needed to
signal whenever modifier support is available or not.  The code needs to
cake care to not send the modifier field in case the host doesn't
support it.  Naming the modifier field "drm_modifier" is probably a good
idea to make clear that we'll use the drm modifier as-is.

A virtio-spec update is needed to document the protocol update.

take care,
  Gerd