Re: [PATCH v4 1/6] io_uring/mock: add basic infra for test mock files

[Jens Axboe <axboe@kernel.dk>]

On 5/30/25 7:57 AM, Pavel Begunkov wrote:
> On 5/30/25 14:28, Jens Axboe wrote:
>> On 5/30/25 6:51 AM, Pavel Begunkov wrote:
>>> diff --git a/init/Kconfig b/init/Kconfig
>>> index 63f5974b9fa6..9e8a5b810804 100644
>>> --- a/init/Kconfig
>>> +++ b/init/Kconfig
>>> @@ -1774,6 +1774,17 @@ config GCOV_PROFILE_URING
>>>         the io_uring subsystem, hence this should only be enabled for
>>>         specific test purposes.
>>>   +config IO_URING_MOCK_FILE
>>> +    tristate "Enable io_uring mock files (Experimental)" if EXPERT
>>> +    default n
>>> +    depends on IO_URING && KASAN
>>> +    help
>>> +      Enable mock files for io_uring subststem testing. The ABI might
>>> +      still change, so it's still experimental and should only be enabled
>>> +      for specific test purposes.
>>> +
>>> +      If unsure, say N.
>>
>> As mentioned in the other email, I don't think we should include KASAN
>> here.
>>
>>> +struct io_uring_mock_create {
>>> +    __u32        out_fd;
>>> +    __u32        flags;
>>> +    __u64        __resv[15];
>>> +};
>>
>> Do we want to have a type here for this? Eg regular file, pipe, socket,
>> etc?
> 
> That can be added when/if they're mocked. This set tries to atomize
> file rw execution characteristics, pipes should be just a particular
> set of those (e.g. +option stream vs offset based file). There might
> be some interest to test some interactions like with page cache, but
> that's beyond the scope, at least for now.

That's fine, guess it's easy to add a type when everything is checked
for zeroes upfront.

-- 
Jens Axboe