Function pmap_init_pv_table

freebsd/amd64/amd64/pmap.c:2199–2267

#ifdef NUMA
static void
pmap_init_pv_table(void)
{
	struct pmap_large_md_page *pvd;
	vm_size_t s;
	long start, end, highest, pv_npg;
	int domain, i, j, pages;

	/*
	 * We strongly depend on the size being a power of two, so the assert
	 * is overzealous. However, should the struct be resized to a
	 * different power of two, the code below needs to be revisited.
	 */
	CTASSERT((sizeof(*pvd) == 64));

	/*
	 * Calculate the size of the array.
	 */
	pmap_last_pa = vm_phys_segs[vm_phys_nsegs - 1].end;
	pv_npg = howmany(pmap_last_pa, NBPDR);
	s = (vm_size_t)pv_npg * sizeof(struct pmap_large_md_page);
	s = round_page(s);
	pv_table = (struct pmap_large_md_page *)kva_alloc(s);
	if (pv_table == NULL)
		panic("%s: kva_alloc failed\n", __func__);

	/*
	 * Iterate physical segments to allocate space for respective pages.
	 */
	highest = -1;
	s = 0;
	for (i = 0; i < vm_phys_nsegs; i++) {
		end = vm_phys_segs[i].end / NBPDR;
		domain = vm_phys_segs[i].domain;

		if (highest >= end)
			continue;

		start = highest + 1;
		pvd = &pv_table[start];

		pages = end - start + 1;
		s = round_page(pages * sizeof(*pvd));
		highest = start + (s / sizeof(*pvd)) - 1;

		for (j = 0; j < s; j += PAGE_SIZE) {
			vm_page_t m = vm_page_alloc_domain(NULL, 0,
			    domain, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ);
			if (m == NULL)
				panic("vm_page_alloc_domain failed for %lx\n", (vm_offset_t)pvd + j);
			pmap_qenter((vm_offset_t)pvd + j, &m, 1);
		}

		for (j = 0; j < s / sizeof(*pvd); j++) {
			rw_init_flags(&pvd->pv_lock, "pmap pv list", RW_NEW);
			TAILQ_INIT(&pvd->pv_page.pv_list);
			pvd->pv_page.pv_gen = 0;
			pvd->pv_page.pat_mode = 0;