Function pmap_remove_all

freebsd/mips/mips/pmap.c:1952–2014

 */

void
pmap_remove_all(vm_page_t m)
{
	pv_entry_t pv;
	pmap_t pmap;
	pd_entry_t *pde;
	pt_entry_t *pte, tpte;

	KASSERT((m->oflags & VPO_UNMANAGED) == 0,
	    ("pmap_remove_all: page %p is not managed", m));
	rw_wlock(&pvh_global_lock);

	if (m->md.pv_flags & PV_TABLE_REF)
		vm_page_aflag_set(m, PGA_REFERENCED);

	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
		pmap = PV_PMAP(pv);
		PMAP_LOCK(pmap);

		/*
		 * If it's last mapping writeback all caches from
		 * the page being destroyed
	 	 */
		if (TAILQ_NEXT(pv, pv_list) == NULL)
			mips_dcache_wbinv_range_index(pv->pv_va, PAGE_SIZE);

		pmap->pm_stats.resident_count--;

		pde = pmap_pde(pmap, pv->pv_va);
		KASSERT(pde != NULL && *pde != 0, ("pmap_remove_all: pde"));
		pte = pmap_pde_to_pte(pde, pv->pv_va);

		tpte = *pte;
		if (is_kernel_pmap(pmap))
			*pte = PTE_G;
		else
			*pte = 0;

		if (pte_test(&tpte, PTE_W))
			pmap->pm_stats.wired_count--;

		/*
		 * Update the vm_page_t clean and reference bits.
		 */
		if (pte_test(&tpte, PTE_D)) {
			KASSERT(!pte_test(&tpte, PTE_RO),
			    ("%s: modified page not writable: va: %p, pte: %#jx",
			    __func__, (void *)pv->pv_va, (uintmax_t)tpte));
			vm_page_dirty(m);
		}

		if (!pmap_unuse_pt(pmap, pv->pv_va, *pde))
			pmap_invalidate_page(pmap, pv->pv_va);

		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
		free_pv_entry(pmap, pv);
		PMAP_UNLOCK(pmap);
	}