Re: [PATCH v10] vfio: ABI for mdev display dma-buf operation

[Gerd Hoffmann <kraxel@redhat.com>]

> +/**
> + * VFIO_DEVICE_QUERY_GFX_PLANE - _IOW(VFIO_TYPE, VFIO_BASE + 14,
> + *                           struct vfio_device_query_gfx_plane)
> + * Return: 0 on success, -errno on failure.
> + */
> +
> +struct vfio_device_gfx_plane_info {
> +	__u64 start;
> +	__u64 drm_format_mod;
> +	__u32 drm_format;
> +	__u32 width;
> +	__u32 height;
> +	__u32 stride;
> +	__u32 size;
> +	__u32 x_pos;
> +	__u32 y_pos;
> +};

Do we want keep that as separate struct?  Given we now have only a
single struct using that as sub-struct it looks pointless, at least
from a API point of view.  Does the driver use the struct internally?

> +
> +struct vfio_device_query_gfx_plane {
> +	__u32 argsz;
> +	__u32 flags;
> +	struct vfio_device_gfx_plane_info plane_info;
> +	__u32 plane_type;
> +	__s32 fd; /* dma-buf fd */
> +	__u32 plane_id;

What is plane_id?

cheers,
  Gerd