vn_bdev_openpath
error = vn_bdev_openpath(pb, &vpp[i], l);
ret = vn_bdev_openpath(pb, &vp, l);
error = vn_bdev_openpath(dev_pb, &dmp->pdev_vnode, curlwp);
error = vn_bdev_openpath(pb, &vp, curlwp);
retcode = vn_bdev_openpath(pb, &vp, curlwp);
int vn_bdev_openpath(struct pathbuf *pb, struct vnode **, struct lwp *);