[PATCH 1/2] drm/virtio: Defer the host dumb buffer creation

[Gerd Hoffmann]

> +static void virtio_gpu_deferred_create(struct virtio_gpu_object *bo,
> +				       struct virtio_gpu_device *vgdev,
> +				       const struct drm_mode_fb_cmd2 *mode_cmd)
> +{
> +	struct virtio_gpu_object_params params = { 0 };
> +
> +	params.format = virtio_gpu_translate_format(mode_cmd->pixel_format);
> +	params.width = mode_cmd->width;
> +	params.height = mode_cmd->height;
> +	params.size = params.height * params.width * 4;
> +	params.size = ALIGN(params.size, PAGE_SIZE);
> +	params.dumb = true;

I'd suggest to simply store the complete virtio_gpu_object_params struct
in virtio_gpu_object instead of re-creating it here.

> diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
> index 64c236169db88..8d1e8dcfa8c15 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_drv.h
> +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
> @@ -93,6 +93,9 @@ struct virtio_gpu_object {
>  	bool dumb;
>  	bool created;
>  	bool host3d_blob, guest_blob;
> +	bool deferred;
> +	struct virtio_gpu_mem_entry *ents;
> +	unsigned int nents;
>  	uint32_t blob_mem, blob_flags;

Put them into a new block separated by newline, add a comment saying
those are needed for virtio_gpu_deferred_create?

> @@ -229,9 +231,14 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
>  						  objs, fence);
>  		virtio_gpu_object_attach(vgdev, bo, ents, nents);
>  	} else {
> -		virtio_gpu_cmd_create_resource(vgdev, bo, params,
> -					       objs, fence);
> -		virtio_gpu_object_attach(vgdev, bo, ents, nents);
> +		/* Fence is used only with blob or virgl */
> +		WARN_ONCE(fence != NULL, "deferred doesn't support fence\n");

Additionally check for param->dumb to take the deferred code path?  That
should make sure there is no fence.

take care,
  Gerd