mnt_add_to_ns
mnt_add_to_ns(n, m);
mnt_add_to_ns(ns, p);
mnt_add_to_ns(new_ns, mnt);
mnt_add_to_ns(new_ns, q);
mnt_add_to_ns(ns, mnt);
mnt_add_to_ns(ns, mnt);
mnt_add_to_ns(&init_mnt_ns, p);