Function pmap_remove_all

freebsd/arm64/arm64/pmap.c:3141–3231

 */

void
pmap_remove_all(vm_page_t m)
{
	struct md_page *pvh;
	pv_entry_t pv;
	pmap_t pmap;
	struct rwlock *lock;
	pd_entry_t *pde, tpde;
	pt_entry_t *pte, tpte;
	vm_offset_t va;
	struct spglist free;
	int lvl, pvh_gen, md_gen;

	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
	    ("pmap_remove_all: page %p is not managed", m));
	SLIST_INIT(&free);
	lock = VM_PAGE_TO_PV_LIST_LOCK(m);
	pvh = (m->flags & PG_FICTITIOUS) != 0 ? &pv_dummy : page_to_pvh(m);
retry:
	rw_wlock(lock);
	while ((pv = TAILQ_FIRST(&pvh->pv_list)) != NULL) {
		pmap = PV_PMAP(pv);
		if (!PMAP_TRYLOCK(pmap)) {
			pvh_gen = pvh->pv_gen;
			rw_wunlock(lock);
			PMAP_LOCK(pmap);
			rw_wlock(lock);
			if (pvh_gen != pvh->pv_gen) {
				rw_wunlock(lock);
				PMAP_UNLOCK(pmap);
				goto retry;
			}
		}
		va = pv->pv_va;
		pte = pmap_pte(pmap, va, &lvl);
		KASSERT(pte != NULL,
		    ("pmap_remove_all: no page table entry found"));
		KASSERT(lvl == 2,
		    ("pmap_remove_all: invalid pte level %d", lvl));

		pmap_demote_l2_locked(pmap, pte, va, &lock);
		PMAP_UNLOCK(pmap);
	}
	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
		pmap = PV_PMAP(pv);
		PMAP_ASSERT_STAGE1(pmap);
		if (!PMAP_TRYLOCK(pmap)) {
			pvh_gen = pvh->pv_gen;
			md_gen = m->md.pv_gen;
			rw_wunlock(lock);
			PMAP_LOCK(pmap);
			rw_wlock(lock);
			if (pvh_gen != pvh->pv_gen || md_gen != m->md.pv_gen) {
				rw_wunlock(lock);
				PMAP_UNLOCK(pmap);
				goto retry;
			}
		}