Re: [PATCH v1] drm/virtio: Extend blob UAPI with deferred-mapping hinting

[Dmitry Osipenko]

On 2/14/25 20:45, Rob Clark wrote:
> On Sun, Jan 26, 2025 at 12:43 PM Dmitry Osipenko
> <dmitry.osipenko@xxxxxxxxxxxxx> wrote:
>>
>> If userspace never maps GEM object, then BO wastes hostmem space
>> because VirtIO-GPU driver maps VRAM BO at the BO's creating time.
>>
>> Make mappings on-demand by adding new RESOURCE_CREATE_BLOB IOCTL/UAPI
>> hinting flag telling that host mapping should be deferred until first
>> mapping is made when the flag is set by userspace.
>>
>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
> 
> I suppose we could have just added a new blob_flag, but then userspace
> would need to probe the kernel to see whether the new flag was
> supported.  (Which isn't a big deal, that sort of thing is done in
> many places.)  But extending the struct does make it more transparent
> to userspace.  Either way,
> 
> Reviewed-by: Rob Clark <robdclark@xxxxxxxxx

Thanks for the review!

-- 
Best regards,
Dmitry