Re: [PATCH v2 6/8] fuse: add user_ prefix to userspace headers and payload fields

[Joanne Koong <joannelkoong@gmail.com>]

On Mon, Oct 27, 2025 at 6:32 PM Caleb Sander Mateos
<csander@purestorage.com> wrote:
>
> On Mon, Oct 27, 2025 at 3:29 PM Joanne Koong <joannelkoong@gmail.com> wrote:
> >
> > Rename the headers and payload fields to user_headers and user_payload.
> > This makes it explicit that these pointers reference userspace addresses
> > and prepares for upcoming fixed buffer support, where there will be
> > separate fields for kernel-space pointers to the payload and headers.
> >
> > Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
> > ---
> >  fs/fuse/dev_uring.c   | 17 ++++++++---------
> >  fs/fuse/dev_uring_i.h |  4 ++--
> >  2 files changed, 10 insertions(+), 11 deletions(-)
> >
> > diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
> > index d96368e93e8d..c814b571494f 100644
> > --- a/fs/fuse/dev_uring.c
> > +++ b/fs/fuse/dev_uring.c
> > @@ -585,11 +585,11 @@ static void __user *get_user_ring_header(struct fuse_ring_ent *ent,
> >  {
> >         switch (type) {
> >         case FUSE_URING_HEADER_IN_OUT:
> > -               return &ent->headers->in_out;
> > +               return &ent->user_headers->in_out;
> >         case FUSE_URING_HEADER_OP:
> > -               return &ent->headers->op_in;
> > +               return &ent->user_headers->op_in;
> >         case FUSE_URING_HEADER_RING_ENT:
> > -               return &ent->headers->ring_ent_in_out;
> > +               return &ent->user_headers->ring_ent_in_out;
> >         }
> >
> >         WARN_ON_ONCE(1);
> > @@ -645,7 +645,7 @@ static int fuse_uring_copy_from_ring(struct fuse_ring *ring,
> >         if (err)
> >                 return err;
> >
> > -       err = import_ubuf(ITER_SOURCE, ent->payload, ring->max_payload_sz,
> > +       err = import_ubuf(ITER_SOURCE, ent->user_payload, ring->max_payload_sz,
> >                           &iter);
> >         if (err)
> >                 return err;
> > @@ -674,7 +674,7 @@ static int fuse_uring_args_to_ring(struct fuse_ring *ring, struct fuse_req *req,
> >                 .commit_id = req->in.h.unique,
> >         };
> >
> > -       err = import_ubuf(ITER_DEST, ent->payload, ring->max_payload_sz, &iter);
> > +       err = import_ubuf(ITER_DEST, ent->user_payload, ring->max_payload_sz, &iter);
> >         if (err) {
> >                 pr_info_ratelimited("fuse: Import of user buffer failed\n");
> >                 return err;
> > @@ -710,8 +710,7 @@ static int fuse_uring_args_to_ring(struct fuse_ring *ring, struct fuse_req *req,
> >
> >         ent_in_out.payload_sz = cs.ring.copied_sz;
> >         return copy_header_to_ring(ent, FUSE_URING_HEADER_RING_ENT,
> > -                                  &ent_in_out,
> > -                                  sizeof(ent_in_out));
> > +                                  &ent_in_out, sizeof(ent_in_out));
>
> nit: looks like an unnecessary formatting change here. Either drop it
> or move it to the earlier commit that added these lines?

I will move this to the earlier commit that added this.

Thanks,
Joanne
>
> Best,
> Caleb
>
> >  }
> >
> >  static int fuse_uring_copy_to_ring(struct fuse_ring_ent *ent,
> > @@ -1104,8 +1103,8 @@ fuse_uring_create_ring_ent(struct io_uring_cmd *cmd,
> >         INIT_LIST_HEAD(&ent->list);
> >
> >         ent->queue = queue;
> > -       ent->headers = iov[0].iov_base;
> > -       ent->payload = iov[1].iov_base;
> > +       ent->user_headers = iov[0].iov_base;
> > +       ent->user_payload = iov[1].iov_base;
> >
> >         atomic_inc(&ring->queue_refs);
> >         return ent;
> > diff --git a/fs/fuse/dev_uring_i.h b/fs/fuse/dev_uring_i.h
> > index 51a563922ce1..381fd0b8156a 100644
> > --- a/fs/fuse/dev_uring_i.h
> > +++ b/fs/fuse/dev_uring_i.h
> > @@ -39,8 +39,8 @@ enum fuse_ring_req_state {
> >  /** A fuse ring entry, part of the ring queue */
> >  struct fuse_ring_ent {
> >         /* userspace buffer */
> > -       struct fuse_uring_req_header __user *headers;
> > -       void __user *payload;
> > +       struct fuse_uring_req_header __user *user_headers;
> > +       void __user *user_payload;
> >
> >         /* the ring queue that owns the request */
> >         struct fuse_ring_queue *queue;
> > --
> > 2.47.3
> >