nfs_sillyrename
static int nfs_sillyrename(struct vnode *, struct vnode *,
error = nfs_sillyrename(dvp, vp, cnp);
tvp->v_type != VDIR && !nfs_sillyrename(tdvp, tvp, tcnp)) {
int nfs_sillyrename(struct vnode *, struct vnode *, struct componentname *,
error = nfs_sillyrename(dvp, vp, cnp, false);