Re: [PATCH v2 5/8] fuse: use enum types for header copying

[Joanne Koong <joannelkoong@gmail.com>]

On Wed, Nov 5, 2025 at 3:01 PM Bernd Schubert <bernd@bsbernd.com> wrote:
>
> On 10/27/25 23:28, Joanne Koong wrote:
> > Use enum types to identify which part of the header needs to be copied.
> > This improves the interface and will simplify both kernel-space and
> > user-space header addresses when fixed buffer support is added.
> >
> > Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
> > ---
> >  fs/fuse/dev_uring.c | 55 ++++++++++++++++++++++++++++++++++++---------
> >  1 file changed, 45 insertions(+), 10 deletions(-)
> >
> > diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
> > index faa7217e85c4..d96368e93e8d 100644
> > --- a/fs/fuse/dev_uring.c
> > +++ b/fs/fuse/dev_uring.c
> > @@ -31,6 +31,12 @@ struct fuse_uring_pdu {
> >
> >  static const struct fuse_iqueue_ops fuse_io_uring_ops;
> >
> > +enum fuse_uring_header_type {
> > +     FUSE_URING_HEADER_IN_OUT,
>
> In post review of my own names, headers->in_out is rather hard to
> understand, I would have probably chosen "msg_in_out" now.
> With that _maybe_ FUSE_URING_HEADER_MSG_IN_OUT?

Ahh I personally find "msg" a bit more confusing because "message"
makes me think it refers just to the payload since the whole thing is
usually called the request. So if we had to rename it, maybe
FUSE_URING_HEADER_REQ_IN_OUT? Though I do like your original naming of
it, FUSE_URING_HEADER_IN_OUT since FUSE_URING_FUSE_HEADER_IN_OUT
sounds a little redundant.

I'll add some comments on top of this too, eg "/*struct fuse_in_header
/ struct_fuse_out_header */, to clarify.

>
> > +     FUSE_URING_HEADER_OP,
> > +     FUSE_URING_HEADER_RING_ENT,
> > +};
> > @@ -800,7 +835,7 @@ static void fuse_uring_commit(struct fuse_ring_ent *ent, struct fuse_req *req,
> >       struct fuse_conn *fc = ring->fc;
> >       ssize_t err = 0;
> >
> > -     err = copy_header_from_ring(&req->out.h, &ent->headers->in_out,
> > +     err = copy_header_from_ring(ent, FUSE_URING_HEADER_IN_OUT, &req->out.h,
> >                                   sizeof(req->out.h));
> >       if (err) {
> >               req->out.h.error = err;
>
>
> Reviewed-by: Bernd Schubert <bschubert@ddn.com>

Thanks for reviewing the patches!