> +/*
> + * Unlike blk_rq_map_user () this is only for fixed-buffer async passthrough.
> + * And hopefully faster as well.
> + */
This belongs into io_uring.c. And that hopeful comment needs to be
validated and removed.
> +int nvme_rq_map_user_fixedb(struct request_queue *q, struct request *rq,
> + void __user *ubuf, unsigned long len, gfp_t gfp_mask,
> + struct io_uring_cmd *ioucmd)
> +{
> + struct iov_iter iter;
> + size_t iter_count, nr_segs;
> + struct bio *bio;
> + int ret;
> +
> + /*
> + * Talk to io_uring to obtain BVEC iterator for the buffer.
> + * And use that iterator to form bio/request.
> + */
> + ret = io_uring_cmd_import_fixed(ubuf, len, rq_data_dir(rq), &iter,
> + ioucmd);
io_uring_cmd_import_fixed takes a non-__user pointer, so this will cause
a sparse warning.
