Re: [PATCH V3 05/12] io_uring: bpf: extend io_uring with bpf struct_ops

[Ming Lei <ming.lei@redhat.com>]

On Wed, Mar 25, 2026 at 08:09:03PM -0600, Jens Axboe wrote:
> On 3/24/26 10:37 AM, Ming Lei wrote:
> >  int io_uring_bpf_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
> >  {
> > +	struct uring_bpf_data *data = io_kiocb_to_cmd(req, struct uring_bpf_data);
> > +	u32 opf = READ_ONCE(sqe->bpf_op_flags);
> > +	unsigned char bpf_op = uring_bpf_get_op(opf);
> > +	const struct uring_bpf_ops *ops;
> > +
> > +	if (unlikely(!(req->ctx->flags & IORING_SETUP_BPF_EXT)))
> > +		goto fail;
> > +
> > +	if (bpf_op >= IO_RING_MAX_BPF_OPS)
> > +		return -EINVAL;
> > +
> > +	ops = req->ctx->bpf_ext_ops[bpf_op].ops;
> > +	data->opf = opf;
> > +	data->ops = ops;
> > +	if (ops && ops->prep_fn)
> > +		return ops->prep_fn(data, sqe);
> > +fail:
> >  	return -EOPNOTSUPP;
> >  }
> 
> Any early exit should ensure 'data' is sane, so that the cleanup doesn't
> potentially touch uninitialized crap. This is something that has bit us
> in the past. Not an issue for this patch that adds the code, but it will
> be once the next patch is applied. Better to clear ->opf/ops here
> upfront, so that we never leave this function without 'data' being fully
> initialized.

But ->cleanup() is only called in case of REQ_F_NEED_CLEANUP.

Or maybe you mean other cleanup instead of ->cleanup()?


Thanks,
Ming