Re: [igt-dev] [PATCH v19 1/6] include/drm-uapi: import i915_drm.h header file

Tvrtko Ursulin
2019-04-08T16:56:03Z

On 08/04/2019 17:47, Andi Shyti wrote:
> Hi Tvrtko,
>
>>> This header file is imported in order to include the two new
>>> ioctls DRM_IOCTL_I915_GEM_CONTEXT_SETPARAM,
>>> DRM_IOCTL_I915_GEM_CONTEXT_GETPARAM and DRM_IOCTL_I915_QUERY.
>>>
>>> Signed-off-by: Andi Shyti <andi.shyti@intel.com>
>>> ---
>>> include/drm-uapi/i915_drm.h | 361 ++++++++++++++++++++++++++++++------
>>> 1 file changed, 304 insertions(+), 57 deletions(-)
>>>
>>> diff --git a/include/drm-uapi/i915_drm.h b/include/drm-uapi/i915_drm.h
>>> index 4ae1c6ff6ae6..2bbad08eb9d2 100644
>>> --- a/include/drm-uapi/i915_drm.h
>>> +++ b/include/drm-uapi/i915_drm.h
>>> @@ -62,6 +62,26 @@ extern "C" {
>>> #define I915_ERROR_UEVENT "ERROR"
>>> #define I915_RESET_UEVENT "RESET"
>>> +/*
>>> + * i915_user_extension: Base class for defining a chain of extensions
>>> + *
>>> + * Many interfaces need to grow over time. In most cases we can simply
>>> + * extend the struct and have userspace pass in more data. Another option,
>>> + * as demonstrated by Vulkan's approach to providing extensions for forward
>>> + * and backward compatibility, is to use a list of optional structs to
>>> + * provide those extra details.
>>> + *
>>> + * The key advantage to using an extension chain is that it allows us to
>>> + * redefine the interface more easily than an ever growing struct of
>>> + * increasing complexity, and for large parts of that interface to be
>>> + * entirely optional. The downside is more pointer chasing; chasing across
>>> + * the boundary with pointers encapsulated inside u64.
>>> + */
>>> +struct i915_user_extension {
>>> + __u64 next_extension;
>>> + __u64 name;
>>> +};
>>
>> Just a note to not merge this version since my branch has accidentally
>> diverged from latest drm-tip in this respect.
>
> yes, it slipped off my mind. Do you have any plans to rebase your
> branch? I would send the patches today.

I do have plans but I won't make it today. Will let you know.

Regards,

Tvrtko