[Intel-gfx] [PATCH v5] drm/i915: Engine discovery query

[Chris Wilson]

Quoting Chris Wilson (2018-10-03 13:28:09)
> Quoting Tvrtko Ursulin (2018-10-03 10:58:55)
> > +static int
> > +query_engine_info(struct drm_i915_private *i915,
> > +                 struct drm_i915_query_item *query_item)
> > +{
> > +       for_each_engine(engine, i915, id) {
> > +               struct drm_i915_engine_info info;
> > +
> > +               if (__copy_from_user(&info, info_ptr, sizeof(info)))
> > +                       return -EFAULT;
> > +
> > +               if (memcmp(&info, &zero_info, sizeof(info)))
> > +                       return -EINVAL;
> 
> You want to have this be an in/out?

Fwiw, you can use memchr_inv() instead of having a zeroed struct.
-Chris