blk_rq_map_user_io
EXPORT_SYMBOL(blk_rq_map_user_io);
ret = blk_rq_map_user_io(req, NULL, nvme_to_user_ptr(ubuffer),
ret = blk_rq_map_user_io(rq, NULL, hdr->dxferp, hdr->dxfer_len,
res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,
int blk_rq_map_user_io(struct request *, struct rq_map_data *,