Function pmap_remove_pte1

freebsd/arm/arm/pmap-v6.c:3610–3667

* Do the things to unmap a section in a process */

 *  Do the things to unmap a section in a process
 */
static void
pmap_remove_pte1(pmap_t pmap, pt1_entry_t *pte1p, vm_offset_t sva,
    struct spglist *free)
{
	pt1_entry_t opte1;
	struct md_page *pvh;
	vm_offset_t eva, va;
	vm_page_t m;

	PDEBUG(6, printf("%s(%p): va %#x pte1 %#x at %p\n", __func__, pmap, sva,
	    pte1_load(pte1p), pte1p));

	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
	KASSERT((sva & PTE1_OFFSET) == 0,
	    ("%s: sva is not 1mpage aligned", __func__));

	/*
	 * Clear and invalidate the mapping. It should occupy one and only TLB
	 * entry. So, pmap_tlb_flush() called with aligned address should be
	 * sufficient.
	 */
	opte1 = pte1_load_clear(pte1p);
	pmap_tlb_flush(pmap, sva);

	if (pte1_is_wired(opte1))
		pmap->pm_stats.wired_count -= PTE1_SIZE / PAGE_SIZE;
	pmap->pm_stats.resident_count -= PTE1_SIZE / PAGE_SIZE;
	if (pte1_is_managed(opte1)) {
		pvh = pa_to_pvh(pte1_pa(opte1));
		pmap_pvh_free(pvh, pmap, sva);
		eva = sva + PTE1_SIZE;
		for (va = sva, m = PHYS_TO_VM_PAGE(pte1_pa(opte1));
		    va < eva; va += PAGE_SIZE, m++) {
			if (pte1_is_dirty(opte1))
				vm_page_dirty(m);
			if (opte1 & PTE1_A)
				vm_page_aflag_set(m, PGA_REFERENCED);
			if (TAILQ_EMPTY(&m->md.pv_list) &&
			    TAILQ_EMPTY(&pvh->pv_list))
				vm_page_aflag_clear(m, PGA_WRITEABLE);
		}
	}
	if (pmap == kernel_pmap) {
		/*
		 * L2 page table(s) can't be removed from kernel map as
		 * kernel counts on it (stuff around pmap_growkernel()).
		 */
		 pmap_remove_kernel_pte1(pmap, pte1p, sva);
	} else {
		/*
		 * Get associated L2 page table page.
		 * It's possible that the page was never allocated.
		 */
		m = pmap_pt2_page(pmap, sva);
		if (m != NULL)
			pmap_unwire_pt2_all(pmap, sva, m, free);
	}
}