TLB_REFTRAP
pte = PTE_PROT(TLB_REFTRAP);
(pte & PTE_PROT(TLB_UNCACHEABLE|TLB_DIRTY|TLB_REFTRAP));
pte = pa | PTE_PROT(TLB_WIRED | TLB_REFTRAP |
pmap_changebit(pg, PTE_PROT(TLB_REFTRAP), 0)
#define pmap_is_referenced(pg) pmap_testbit(pg, PTE_PROT(TLB_REFTRAP))
#define PVF_REF PTE_PROT(TLB_REFTRAP) /* pg/mp (inv) is referenced */