the ent
is the same ent for the request that's committed and the next fetched
request). Because of this we can just reuse the same headers_iter and
call io_uring_fixed_index_put() after we're done copying over the next
request. I can add a comment about this to make this more clear.
When the request doesn't have a payload, no ring entry gets used for
the request. The check for this happens in fuse_uring_prep_buffer()

static int fuse_uring_prep_buffer(struct fuse_ring_ent *ent,
                                  struct fuse_req *req, unsigned issue_flags)
{
        ...
        /* no payload to copy, can skip selecting a buffer */
        if (!fuse_uring_req_has_payload(req))
                return 0;

        return fuse_uring_select_buffer(ent, issue_flags);
}
Ok, I'll update the "Fetching the next request is absolutely required" comment.

Thanks,
Joanne[PATCH v4 19/25] fuse: add io-uring kernel-managed buffer ringJoanne Koong <joannelkoong@gmail.com> undefinedBernd Schubert <bernd@bsbernd.com> undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined…