Re: [Intel-gfx] [RFC PATCH 2/3] drm/ipvr: drm driver for vxd392

David Herrmann
2014-10-16T13:47:08Z

Hi

On Thu, Oct 16, 2014 at 3:39 PM, Cheng, Yao <yao.cheng@intel.com> wrote:
> Accepted :) I will update the patch to implement the mmap interface and remove the legacy MMAP_IOCTL.
> BTW I didn't see a field to get mmap_offset in struct drm_gem_open, I guess something like a new "GET_MMAP_OFFSET_IOCTL" need be added to support mapping flinked/primed BO, is it?

Yes. There is currently no generic interface to get mmap offsets for
any gem bo (because some of them may not be mapped from user-space or
require extra parameters).

So, either support dumb-buffers (if you don't need any advanced
parameters like tiling or cache constraints), or add an
MMAP_OFFSET_IOCTL like you proposed (and most drivers do so).

Thanks
David