TLB_WRITE
((pte | ppte) & PTE_PROT(TLB_WRITE)) != 0;
(pte & PTE_PROT(TLB_WRITE))) {
pmap_changebit(pg, 0, PTE_PROT(TLB_WRITE));
#define PVF_WRITE PTE_PROT(TLB_WRITE) /* pg/mp is writable */
#define TLB_AR_RW TLB_READ|TLB_WRITE
#define TLB_AR_RWX TLB_READ|TLB_WRITE|TLB_EXECUTE