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

[Caleb Sander Mateos]

On Wed, Sep 2, 2026 at 6:02 PM Ming Lei <tom.leiming@xxxxxxxxx> wrote:
>
> On Wed, Sep 2, 2026 at 6:05 PM Caleb Sander Mateos
> <csander@xxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxx>
> > ---
> >  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.

Best,
Caleb