umusers_t
umu_add(umusers_t *umu, const umem_bufctl_audit_t *bcp,
umause1(uintptr_t addr, const umem_bufctl_audit_t *bcp, umusers_t *umu)
umause2(uintptr_t addr, const umem_bufctl_audit_t *bcp, umusers_t *umu)
umusers_t umu;