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

[Bernd Schubert <bernd@bsbernd.com>]

On 11/6/25 22:59, Joanne Koong wrote:
> 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.

FUSE_URING_HEADER_REQ_IN_OUT sounds nice to me. Renaming was just a
suggestion. Let's keep the current name if you prefer that.

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

Comments are always helpful :)

> 
>>
>>> +     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!
>