On Wed, Jul 12, 2017 at 02:31:40AM +0000, Zhang, Tina wrote: > > > > -----Original Message----- > > From: intel-gvt-dev [mailto:[email protected]] On > > Behalf Of Daniel Vetter > > Sent: Tuesday, July 11, 2017 5:13 PM > > To: Gerd Hoffmann <[email protected]> > > Cc: Tian, Kevin <[email protected]>; [email protected]; intel- > > [email protected]; [email protected]; > > [email protected]; [email protected]; Kirti Wankhede > > <[email protected]>; Lv, Zhiyuan <[email protected]>; > > [email protected]; Zhang, Tina <[email protected]>; intel-gvt- > > [email protected]; Wang, Zhi A <[email protected]> > > Subject: Re: [PATCH v10] vfio: ABI for mdev display dma-buf operation > > > > 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 > The plane_type here, is to ask the mdev vendor driver to return the > information according to the value in field plane_type. So, it's a input > field. > The values in plane_type field is the same of drm_plane_type. And yes, it's > better to use drm_plane_type instead of plane_id.
I have no idea what you mean here, I guess that just shows that discussing an ioctl struct without solid definitions of what field does what and why is not all that useful. What exactly it plane_id for then? This just confused me more ... -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
