Re: [PATCH v4 6/6] selftests/io_uring: add a bpf io_uring selftest

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

On 1/27/26 18:53, Alexei Starovoitov wrote:
> On Tue, Jan 27, 2026 at 10:42 AM Pavel Begunkov <asml.silence@gmail.com> wrote:
>>
>> On 1/27/26 17:32, Alexei Starovoitov wrote:
>>> On Tue, Jan 27, 2026 at 2:15 AM Pavel Begunkov <asml.silence@gmail.com> wrote:
>>>>
>>>> index 000000000000..7a170cb2f388
>>>> --- /dev/null
>>>> +++ b/tools/testing/selftests/io_uring/types.bpf.h
>>>> @@ -0,0 +1,131 @@
>>>> +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
>>>> +#include <linux/types.h>
>>>> +#include <bpf/bpf_helpers.h>
>>>> +
>>>> +struct io_ring_ctx {
>>>> +};
>>>> +
>>>> +struct io_uring_sqe {
>>>> +       __u8    opcode;         /* type of operation for this sqe */
>>>> +       __u8    flags;          /* IOSQE_ flags */
>>>> +       __u16   ioprio;         /* ioprio for the request */
>>>> +       __s32   fd;             /* file descriptor to do IO on */
>>>
>>> 1.
>>> No need to copy paste. Just include vmlinux.h. It's there.
>>>
>>> 2.
>>> drop KF_TRUSTED_ARGS from kfunc. It's a default now and this flag
>>> was removed.
>>
>> Got it, will change both, thanks
>>
>>> 3.
>>> add a runtime logic to check that the return value is either IOU_LOOP_CONTINUE
>>> or IOU_LOOP_STOP or instruct the verifier do it statically.
>>> Otherwise it will be less convenient to extend to other commands,
>>> since the way I read it IOU_LOOP_CONTINUE == 0 aliases to any value > 1.
>>
>> Is there a struct_ops hook that can help with that? check_return_code()
>> has some hard-coded checks, but I can't find anything customizable for
>> struct_ops.
> 
> yep. check_return_code() is the one and you're correct. It's not
> customizable atm. Much simpler to do a runtime check for now and
> improve through the verifier support later.

Makes sense, thanks!

-- 
Pavel Begunkov