Re: [PATCH v8 10/11] virtio-gpu: Register capsets dynamically

[Akihiko Odaki <akihiko.odaki@daynix.com>]

On 2024/04/19 4:00, Dmitry Osipenko wrote:
> From: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
> 
> virtio_gpu_virgl_get_num_capsets will return "num_capsets", but we can't
> assume that capset_index 1 is always VIRGL2 once we'll support more capsets,
> like Venus and DRM capsets. Register capsets dynamically to avoid that problem.
> 
> Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> ---
>   hw/display/virtio-gpu-virgl.c  | 37 ++++++++++++++++++++++------------
>   include/hw/virtio/virtio-gpu.h |  3 +++
>   2 files changed, 27 insertions(+), 13 deletions(-)
> 
> diff --git a/hw/display/virtio-gpu-virgl.c b/hw/display/virtio-gpu-virgl.c
> index eee3816b987f..c0e1ca3ff339 100644
> --- a/hw/display/virtio-gpu-virgl.c
> +++ b/hw/display/virtio-gpu-virgl.c
> @@ -558,19 +558,12 @@ static void virgl_cmd_get_capset_info(VirtIOGPU *g,
>       VIRTIO_GPU_FILL_CMD(info);
>   
>       memset(&resp, 0, sizeof(resp));
> -    if (info.capset_index == 0) {
> -        resp.capset_id = VIRTIO_GPU_CAPSET_VIRGL;
> -        virgl_renderer_get_cap_set(resp.capset_id,
> -                                   &resp.capset_max_version,
> -                                   &resp.capset_max_size);
> -    } else if (info.capset_index == 1) {
> -        resp.capset_id = VIRTIO_GPU_CAPSET_VIRGL2;
> +
> +    if (info.capset_index < g->num_capsets) {
> +        resp.capset_id = g->capset_ids[info.capset_index];
>           virgl_renderer_get_cap_set(resp.capset_id,
>                                      &resp.capset_max_version,
>                                      &resp.capset_max_size);
> -    } else {
> -        resp.capset_max_version = 0;
> -        resp.capset_max_size = 0;
>       }
>       resp.hdr.type = VIRTIO_GPU_RESP_OK_CAPSET_INFO;
>       virtio_gpu_ctrl_response(g, cmd, &resp.hdr, sizeof(resp));
> @@ -1120,12 +1113,30 @@ int virtio_gpu_virgl_init(VirtIOGPU *g)
>       return 0;
>   }
>   
> +static void virtio_gpu_virgl_add_capset(VirtIOGPU *g, uint32_t capset_id)
> +{
> +    g->capset_ids = g_realloc_n(g->capset_ids, g->num_capsets + 1,
> +                                sizeof(*g->capset_ids));
> +    g->capset_ids[g->num_capsets++] = capset_id;
> +}
> +
>   int virtio_gpu_virgl_get_num_capsets(VirtIOGPU *g)
>   {
>       uint32_t capset2_max_ver, capset2_max_size;
> +
> +    if (g->num_capsets) {
> +        return g->num_capsets;
> +    }
> +
> +    /* VIRGL is always supported. */
> +    virtio_gpu_virgl_add_capset(g, VIRTIO_GPU_CAPSET_VIRGL);
> +
>       virgl_renderer_get_cap_set(VIRTIO_GPU_CAPSET_VIRGL2,
> -                              &capset2_max_ver,
> -                              &capset2_max_size);
> +                               &capset2_max_ver,
> +                               &capset2_max_size);
> +    if (capset2_max_ver) {
> +        virtio_gpu_virgl_add_capset(g, VIRTIO_GPU_CAPSET_VIRGL2);
> +    }
>   
> -    return capset2_max_ver ? 2 : 1;
> +    return g->num_capsets;
>   }
> diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h
> index d2a0d542fbb3..3d7d001a85c5 100644
> --- a/include/hw/virtio/virtio-gpu.h
> +++ b/include/hw/virtio/virtio-gpu.h
> @@ -218,6 +218,9 @@ struct VirtIOGPU {
>           QTAILQ_HEAD(, VGPUDMABuf) bufs;
>           VGPUDMABuf *primary[VIRTIO_GPU_MAX_SCANOUTS];
>       } dmabuf;
> +
> +    uint32_t *capset_ids;
> +    uint32_t num_capsets;

Use GArray.