On Wed, Jul 12, 2017 at 02:31:40AM +0000, Zhang, Tina wrote: > > > > -----Original Message----- > > From: intel-gvt-dev [mailto:intel-gvt-dev-bounces@xxxxxxxxxxxxxxxxxxxxx] On > > Behalf Of Daniel Vetter > > Sent: Tuesday, July 11, 2017 5:13 PM > > To: Gerd Hoffmann <kraxel@xxxxxxxxxx> > > Cc: Tian, Kevin <kevin.tian@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; intel- > > gfx@xxxxxxxxxxxxxxxxxxxxx; alex.williamson@xxxxxxxxxx; > > zhenyuw@xxxxxxxxxxxxxxx; chris@xxxxxxxxxxxxxxxxxx; Kirti Wankhede > > <kwankhede@xxxxxxxxxx>; Lv, Zhiyuan <zhiyuan.lv@xxxxxxxxx>; > > daniel@xxxxxxxx; Zhang, Tina <tina.zhang@xxxxxxxxx>; intel-gvt- > > dev@xxxxxxxxxxxxxxxxxxxxx; Wang, Zhi A <zhi.a.wang@xxxxxxxxx> > > 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 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
