Re: [PATCH v5 5/8] iio: core: Add new DMABUF interface infrastructure

Christian König
2024-01-29T13:17:33Z

Am 29.01.24 um 14:06 schrieb Paul Cercueil:
> Hi Christian,
>
> Le lundi 29 janvier 2024 à 13:52 +0100, Christian König a écrit :
>> Am 27.01.24 um 17:50 schrieb Jonathan Cameron:
>>>>>> + iio_buffer_dmabuf_put(attach);
>>>>>> +
>>>>>> +out_dmabuf_put:
>>>>>> + dma_buf_put(dmabuf);
>>>>> As below. Feels like a __free(dma_buf_put) bit of magic would
>>>>> be a
>>>>> nice to have.
>>>> I'm working on the patches right now, just one quick question.
>>>>
>>>> Having a __free(dma_buf_put) requires that dma_buf_put is first
>>>> "registered" as a freeing function using DEFINE_FREE() in
>>>> <linux/dma-
>>>> buf.h>, which has not been done yet.
>>>>
>>>> That would mean carrying a dma-buf specific patch in your tree,
>>>> are you
>>>> OK with that?
>>> Needs an ACK from appropriate maintainer, but otherwise I'm fine
>>> doing
>>> so.  Alternative is to circle back to this later after this code is
>>> upstream.
>> Separate patches for that please, the autocleanup feature is so new
>> that
>> I'm not 100% convinced that everything works out smoothly from the
>> start.
> Separate patches is a given, did you mean outside this patchset?
> Because I can send a separate patchset that introduces scope-based
> management for dma_fence and dma_buf, but then it won't have users.

Outside of the patchset, this is essentially brand new stuff.

IIRC we have quite a number of dma_fence selftests and sw_sync which is
basically code inside the drivers/dma-buf directory only there for
testing DMA-buf functionality.

Convert those over as well and I'm more than happy to upstream this change.

Thanks,
Christian.

>
> Cheers,
> -Paul