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

[Daniel Vetter]

On Tue, Jul 11, 2017 at 08:14:08AM +0200, Gerd Hoffmann wrote:
>   Hi,
> 
> > > +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;
> > > +};
> > > +
> > 
> > It would be better to have comment here about what are expected
> > values
> > for plane_type and plane_id.
> 
> plane_type is DRM_PLANE_TYPE_*.
> 
> yes, a comment saying so would be good, same for drm_format which is
> DRM_FORMAT_*.  While looking at these two: renaming plane_type to
> drm_plane_type (for consistency) is probably a good idea too.
> 
> plane_id needs a specification.

Why do you need plane_type? With universal planes the plane_id along is
sufficient to identify a plane on a given drm device instance. I'd just
remove it.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch