Re: [PATCH v2 7/8] fuse: refactor setting up copy state for payload copying

[Bernd Schubert <bschubert@ddn.com>]

On 10/27/25 23:28, Joanne Koong wrote:
> Add a new helper function setup_fuse_copy_state() to contain the logic
> for setting up the copy state for payload copying.
> 
> Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
> ---
>  fs/fuse/dev_uring.c | 39 +++++++++++++++++++++++++--------------
>  1 file changed, 25 insertions(+), 14 deletions(-)
> 
> diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c
> index c814b571494f..c6b22b14b354 100644
> --- a/fs/fuse/dev_uring.c
> +++ b/fs/fuse/dev_uring.c
> @@ -630,6 +630,28 @@ static int copy_header_from_ring(struct fuse_ring_ent *ent,
>  	return 0;
>  }
>  
> +static int setup_fuse_copy_state(struct fuse_ring *ring, struct fuse_req *req,
> +				 struct fuse_ring_ent* ent, int rw,
> +				 struct iov_iter *iter,
> +				 struct fuse_copy_state *cs)

Maybe 'struct fuse_copy_state *cs' as first argument? Just a suggestion and would
good if it wouldn't end up in the middle when there are more arguments added at some
point.

> +{
> +	int err;
> +
> +	err = import_ubuf(rw, ent->user_payload, ring->max_payload_sz,
> +			  iter);
> +	if (err) {
> +		pr_info_ratelimited("fuse: Import of user buffer failed\n");
> +		return err;
> +	}
> +
> +	fuse_copy_init(cs, rw == ITER_DEST, iter);
> +
> +	cs->is_uring = true;
> +	cs->req = req;
> +
> +	return 0;
> +}
> +
>  static int fuse_uring_copy_from_ring(struct fuse_ring *ring,
>  				     struct fuse_req *req,
>  				     struct fuse_ring_ent *ent)
> @@ -645,15 +667,10 @@ static int fuse_uring_copy_from_ring(struct fuse_ring *ring,
>  	if (err)
>  		return err;
>  
> -	err = import_ubuf(ITER_SOURCE, ent->user_payload, ring->max_payload_sz,
> -			  &iter);
> +	err = setup_fuse_copy_state(ring, req, ent, ITER_SOURCE, &iter, &cs);
>  	if (err)
>  		return err;
>  
> -	fuse_copy_init(&cs, false, &iter);
> -	cs.is_uring = true;
> -	cs.req = req;
> -
>  	return fuse_copy_out_args(&cs, args, ring_in_out.payload_sz);
>  }
>  
> @@ -674,15 +691,9 @@ 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->user_payload, ring->max_payload_sz, &iter);
> -	if (err) {
> -		pr_info_ratelimited("fuse: Import of user buffer failed\n");
> +	err = setup_fuse_copy_state(ring, req, ent, ITER_DEST, &iter, &cs);
> +	if (err)
>  		return err;
> -	}
> -
> -	fuse_copy_init(&cs, true, &iter);
> -	cs.is_uring = true;
> -	cs.req = req;
>  
>  	if (num_args > 0) {
>  		/*


Reviewed-by: Bernd Schubert <bschubert@ddn.com>