[Intel-gfx] [PATCH 11/12] drm/i915: Extend GET_APERTURE ioctl to report available map space

[Tvrtko Ursulin]

On 29/04/16 11:18, Chris Wilson wrote:
> On Fri, Apr 29, 2016 at 11:06:49AM +0100, Tvrtko Ursulin wrote:
>> I don't get it - if we are adding something why not add it in a way
>> that makes it clear and self-contained - what is the downside of
>> what I propose to meet such resistance?
>
> You're suggesting to add a field I'm not going to use. Is any one?
> Until there is an actual use (which would afaict be if one of the
> existing values changed meaning, which itself would be an abi break) I'm
> not convinced we should be designing for the unknowable. If we did need
> to version would we not be better off with a new ioctl?

I am suggesting if we are adding aper_total_size, or whatever it is 
called, to make it usable in an self-contained matter.

My impression was you want aper_total_size so I was simply objecting to 
adding it without being able to directly tell if kernel actually 
supports that extension.

Regards,

Tvrtko