[PATCH v2 1/2] io_uring/cmd: split io_uring_cmd_set_res() from io_uring_cmd_done()

[Jens Axboe]

On 9/3/26 11:34 AM, Caleb Sander Mateos wrote:
> On Wed, Sep 2, 2026 at 6:02?PM Ming Lei <tom.leiming at gmail.com> wrote:
>>
>> On Wed, Sep 2, 2026 at 6:05?PM Caleb Sander Mateos
>> <csander at purestorage.com> wrote:
>>>
>>> In preparation for setting the io_uring NVMe passthru CQE results from
>>> the blk-mq request completion rather than the task work callback, split
>>> out functions io_uring_cmd_set_res{,32}() from __io_uring_cmd_done().
>>> io_uring_cmd_done{,32}() now call io_uring_cmd_set_res{,32}() and then
>>> __io_uring_cmd_done(). This allows __io_uring_cmd_done() to be made
>>> CQE-size-agnostic, with 3 fewer arguments.
>>>
>>> Signed-off-by: Caleb Sander Mateos <csander at purestorage.com>
>>> ---
>>>  include/linux/io_uring/cmd.h | 23 +++++++++++++++++------
>>>  io_uring/uring_cmd.c         | 33 ++++++++++++++++++---------------
>>>  2 files changed, 35 insertions(+), 21 deletions(-)
>>>
>>> diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h
>>> index 331dcbefe72f..67f2ef700c43 100644
>>> --- a/include/linux/io_uring/cmd.h
>>> +++ b/include/linux/io_uring/cmd.h
>>> @@ -50,19 +50,21 @@ int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
>>>                                   const struct iovec __user *uvec,
>>>                                   size_t uvec_segs,
>>>                                   int ddir, struct iov_iter *iter,
>>>                                   unsigned issue_flags);
>>>
>>> +void io_uring_cmd_set_res(struct io_uring_cmd *, s32 ret);
>>> +void io_uring_cmd_set_res32(struct io_uring_cmd *, s32 ret, u64 res2);
>>> +
>>>  /*
>>>   * Completes the request, i.e. posts an io_uring CQE and deallocates @ioucmd
>>>   * and the corresponding io_uring request.
>>>   *
>>>   * Note: the caller should never hard code @issue_flags and is only allowed
>>>   * to pass the mask provided by the core io_uring code.
>>>   */
>>> -void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret, u64 res2,
>>> -                        unsigned issue_flags, bool is_cqe32);
>>> +void __io_uring_cmd_done(struct io_uring_cmd *, unsigned issue_flags);
>>>
>>>  void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
>>>                             io_req_tw_func_t task_work_cb,
>>>                             unsigned flags);
>>>
>>> @@ -105,12 +107,19 @@ static inline int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
>>>                                                 int ddir, struct iov_iter *iter,
>>>                                                 unsigned issue_flags)
>>>  {
>>>         return -EOPNOTSUPP;
>>>  }
>>> -static inline void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret,
>>> -               u64 ret2, unsigned issue_flags, bool is_cqe32)
>>> +static inline void io_uring_cmd_set_res(struct io_uring_cmd *cmd, s32 ret)
>>> +{
>>> +}
>>> +static inline void io_uring_cmd_set_res32(struct io_uring_cmd *cmd, s32 ret,
>>> +                                         u64 res2)
>>> +{
>>> +}
>>> +static inline void __io_uring_cmd_done(struct io_uring_cmd *cmd,
>>> +                                      unsigned issue_flags)
>>>  {
>>>  }
>>>  static inline void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
>>>                             io_req_tw_func_t task_work_cb, unsigned flags)
>>>  {
>>> @@ -171,17 +180,19 @@ static inline void *io_uring_cmd_ctx_handle(struct io_uring_cmd *cmd)
>>>  }
>>>
>>>  static inline void io_uring_cmd_done(struct io_uring_cmd *ioucmd, s32 ret,
>>>                                      unsigned issue_flags)
>>>  {
>>> -       return __io_uring_cmd_done(ioucmd, ret, 0, issue_flags, false);
>>> +       io_uring_cmd_set_res(ioucmd, ret);
>>> +       __io_uring_cmd_done(ioucmd, issue_flags);
>>>  }
>>>
>>>  static inline void io_uring_cmd_done32(struct io_uring_cmd *ioucmd, s32 ret,
>>>                                        u64 res2, unsigned issue_flags)
>>>  {
>>> -       return __io_uring_cmd_done(ioucmd, ret, res2, issue_flags, true);
>>> +       io_uring_cmd_set_res32(ioucmd, ret, res2);
>>> +       __io_uring_cmd_done(ioucmd, issue_flags);
>>>  }
>>>
>>>  int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,
>>>                             void (*release)(void *), unsigned int index,
>>>                             unsigned int issue_flags);
>>> diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
>>> index 726a659f38c3..917b32a921e6 100644
>>> --- a/io_uring/uring_cmd.c
>>> +++ b/io_uring/uring_cmd.c
>>> @@ -136,40 +136,43 @@ void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
>>>         req->io_task_work.func = task_work_cb;
>>>         __io_req_task_work_add(req, flags);
>>>  }
>>>  EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);
>>>
>>> -static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
>>> -                                         u64 extra1, u64 extra2)
>>> +void io_uring_cmd_set_res(struct io_uring_cmd *cmd, s32 ret)
>>>  {
>>> -       req->big_cqe.extra1 = extra1;
>>> -       req->big_cqe.extra2 = extra2;
>>> +       struct io_kiocb *req = cmd_to_io_kiocb(cmd);
>>> +
>>> +       if (ret < 0)
>>> +               req_set_fail(req);
>>> +       io_req_set_res(req, ret, 0);
>>>  }
>>> +EXPORT_SYMBOL_GPL(io_uring_cmd_set_res);
>>> +
>>> +void io_uring_cmd_set_res32(struct io_uring_cmd *cmd, s32 ret, u64 res2)
>>> +{
>>> +       struct io_kiocb *req = cmd_to_io_kiocb(cmd);
>>> +
>>> +       if (ret < 0)
>>> +               req_set_fail(req);
>>> +       io_req_set_res32(req, ret, 0, res2, 0);
>>> +}
>>> +EXPORT_SYMBOL_GPL(io_uring_cmd_set_res32);
>>
>> Both the two helpers can be inline, can't they?
> 
> I also wanted to do that, but req_set_*() are defined in
> io_uring/io_uring.h, an io_uring-private header, whereas
> include/linux/io_uring/cmd.h is a public header. Perhaps the inline
> functions could be moved to include/linux/io_uring_types.h or
> include/linux/io_uring.h. If not, I think we'll have to rely on LTO to
> inline these calls. I'd be curious to hear Jens's thoughts.

Let's just move them to io_uring.h instead.

-- 
Jens Axboe