Re: [PATCH 0/3] io_uring: fixes for provided buffer ring

[Pavel Begunkov <asml.silence@gmail.com>]

On 6/13/22 12:08, Hao Xu wrote:
> On 6/13/22 18:11, Dylan Yudaken wrote:
>> This fixes two problems in the new provided buffer ring feature. One
>> is a simple arithmetic bug (I think this came out from a refactor).
>> The other is due to type differences between head & tail, which causes
>> it to sometimes reuse an old buffer incorrectly.
>>
>> Patch 1&2 fix bugs
>> Patch 3 limits the size of the ring as it's not
>> possible to address more entries with 16 bit head/tail
> 
> Reviewed-by: Hao Xu <howeyxu@tencent.com>
> 
>>
>> I will send test cases for liburing shortly.
>>
>> One question might be if we should change the type of ring_entries
>> to uint16_t in struct io_uring_buf_reg?
> 
> Why not? 5.19 is just rc2 now. So we can assume there is no users using
> it right now I think?

It's fine to change, but might be better if we want to extend it
in the future. Do other pbuf bits allow more than 2^16 buffers?

-- 
Pavel Begunkov