[Mesa-dev] [PATCH v3 3/3] Add a new capabilities for drivers that can't share buffers

[Giovanni Campagna]

2014-06-19 16:16 GMT+02:00 Axel Davy <axel.davy at ens.fr>:
> On 15/06/2014 07:49, Giovanni Campagna wrote :
>
>> From: Giovanni Campagna <gcampagna at src.gnome.org>
>>
>> The kms-dri swrast driver cannot share buffers using the GEM,
>> so it must tell the loader to disable extensions relying on
>> that, without disabling the image DRI extension altogheter
>> (which would prevent the loader from working at all).
>> This requires a new gallium capability (which is queried on
>> the pipe_screen and for swrast drivers it's forwared to the
>> winsys), and requires a new version of the DRI image extension.
>>
> Why does this require a new version of the DRI image extension ?
> Could you just set createImageFromName and CreateImageFromNames to NULL, and
> add checks for that (instead of checking the capability ?
> It's what is done to check if we can import dma-bufs (check if
> createImageFromFds is not NULL).

Yes, but in my opinion a generic getCapabilities() that returns a
bitmask is more flexible, and will allow avoiding version increases
and new vfuncs, should negotiation for new features be needed in the
future.

Giovanni