null_nodeget
int null_nodeget(struct mount *mp, struct vnode *target, struct vnode **vpp);
error = null_nodeget(mp, lowerrootvp, &nullm_rootvp);
error = null_nodeget(mp, mntdata->nullm_lowerrootvp, &vp);
return (null_nodeget(mp, *vpp, vpp));
return (null_nodeget(mp, *vpp, vpp));
error = null_nodeget(mp, ldvp, dvp);
error = null_nodeget(mp, lvp, &vp1);
error = null_nodeget(old_vps[0]->v_mount, **vppp,
error = null_nodeget(mp, lvp, &vp);