1// SPDX-License-Identifier: GPL-2.0-only
  2/* Common code for 32 and 64-bit NUMA */
  3#include <linux/acpi.h>
  4#include <linux/kernel.h>
  5#include <linux/mm.h>
 
  6#include <linux/string.h>
  7#include <linux/init.h>
  8#include <linux/memblock.h>
  9#include <linux/mmzone.h>
 10#include <linux/ctype.h>
 11#include <linux/nodemask.h>
 12#include <linux/sched.h>
 13#include <linux/topology.h>
 
 
 14
 15#include <asm/e820/api.h>
 16#include <asm/proto.h>
 17#include <asm/dma.h>
 18#include <asm/amd_nb.h>
 19
 20#include "numa_internal.h"
 21
 22int numa_off;
 23nodemask_t numa_nodes_parsed __initdata;
 24
 25struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
 26EXPORT_SYMBOL(node_data);
 27
 28static struct numa_meminfo numa_meminfo __initdata_or_meminfo;
 29static struct numa_meminfo numa_reserved_meminfo __initdata_or_meminfo;
 30
 31static int numa_distance_cnt;
 32static u8 *numa_distance;
 33
 34static __init int numa_setup(char *opt)
 35{
 36	if (!opt)
 37		return -EINVAL;
 38	if (!strncmp(opt, "off", 3))
 39		numa_off = 1;
 40#ifdef CONFIG_NUMA_EMU
 41	if (!strncmp(opt, "fake=", 5))
 42		numa_emu_cmdline(opt + 5);
 43#endif
 44#ifdef CONFIG_ACPI_NUMA
 45	if (!strncmp(opt, "noacpi", 6))
 46		acpi_numa = -1;
 47#endif
 
 48	return 0;
 49}
 50early_param("numa", numa_setup);
 51
 52/*
 53 * apicid, cpu, node mappings
 54 */
 55s16 __apicid_to_node[MAX_LOCAL_APIC] = {
 56	[0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
 57};
 58
 59int numa_cpu_node(int cpu)
 60{
 61	int apicid = early_per_cpu(x86_cpu_to_apicid, cpu);
 62
 63	if (apicid != BAD_APICID)
 64		return __apicid_to_node[apicid];
 65	return NUMA_NO_NODE;
 66}
 67
 68cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
 69EXPORT_SYMBOL(node_to_cpumask_map);
 70
 71/*
 72 * Map cpu index to node index
 73 */
 74DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
 75EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
 76
 77void numa_set_node(int cpu, int node)
 78{
 79	int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
 80
 81	/* early setting, no percpu area yet */
 82	if (cpu_to_node_map) {
 83		cpu_to_node_map[cpu] = node;
 84		return;
 85	}
 86
 87#ifdef CONFIG_DEBUG_PER_CPU_MAPS
 88	if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
 89		printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
 90		dump_stack();
 91		return;
 92	}
 93#endif
 94	per_cpu(x86_cpu_to_node_map, cpu) = node;
 95
 96	set_cpu_numa_node(cpu, node);
 97}
 98
 99void numa_clear_node(int cpu)
100{
101	numa_set_node(cpu, NUMA_NO_NODE);
102}
103
104/*
105 * Allocate node_to_cpumask_map based on number of available nodes
106 * Requires node_possible_map to be valid.
107 *
108 * Note: cpumask_of_node() is not valid until after this is done.
109 * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
110 */
111void __init setup_node_to_cpumask_map(void)
112{
113	unsigned int node;
114
115	/* setup nr_node_ids if not done yet */
116	if (nr_node_ids == MAX_NUMNODES)
117		setup_nr_node_ids();
118
119	/* allocate the map */
120	for (node = 0; node < nr_node_ids; node++)
121		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
122
123	/* cpumask_of_node() will now work */
124	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
125}
126
127static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
128				     struct numa_meminfo *mi)
129{
130	/* ignore zero length blks */
131	if (start == end)
132		return 0;
133
134	/* whine about and ignore invalid blks */
135	if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
136		pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
137			nid, start, end - 1);
138		return 0;
139	}
140
141	if (mi->nr_blks >= NR_NODE_MEMBLKS) {
142		pr_err("too many memblk ranges\n");
143		return -EINVAL;
144	}
145
146	mi->blk[mi->nr_blks].start = start;
147	mi->blk[mi->nr_blks].end = end;
148	mi->blk[mi->nr_blks].nid = nid;
149	mi->nr_blks++;
150	return 0;
151}
152
153/**
154 * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
155 * @idx: Index of memblk to remove
156 * @mi: numa_meminfo to remove memblk from
157 *
158 * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
159 * decrementing @mi->nr_blks.
160 */
161void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
162{
163	mi->nr_blks--;
164	memmove(&mi->blk[idx], &mi->blk[idx + 1],
165		(mi->nr_blks - idx) * sizeof(mi->blk[0]));
166}
167
168/**
169 * numa_move_tail_memblk - Move a numa_memblk from one numa_meminfo to another
170 * @dst: numa_meminfo to append block to
171 * @idx: Index of memblk to remove
172 * @src: numa_meminfo to remove memblk from
173 */
174static void __init numa_move_tail_memblk(struct numa_meminfo *dst, int idx,
175					 struct numa_meminfo *src)
176{
177	dst->blk[dst->nr_blks++] = src->blk[idx];
178	numa_remove_memblk_from(idx, src);
179}
180
181/**
182 * numa_add_memblk - Add one numa_memblk to numa_meminfo
183 * @nid: NUMA node ID of the new memblk
184 * @start: Start address of the new memblk
185 * @end: End address of the new memblk
186 *
187 * Add a new memblk to the default numa_meminfo.
188 *
189 * RETURNS:
190 * 0 on success, -errno on failure.
191 */
192int __init numa_add_memblk(int nid, u64 start, u64 end)
193{
194	return numa_add_memblk_to(nid, start, end, &numa_meminfo);
195}
196
197/* Allocate NODE_DATA for a node on the local memory */
198static void __init alloc_node_data(int nid)
199{
200	const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
201	u64 nd_pa;
202	void *nd;
203	int tnid;
204
205	/*
206	 * Allocate node data.  Try node-local memory and then any node.
207	 * Never allocate in DMA zone.
208	 */
209	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
210	if (!nd_pa) {
211		pr_err("Cannot find %zu bytes in any node (initial node: %d)\n",
212		       nd_size, nid);
213		return;
214	}
215	nd = __va(nd_pa);
216
217	/* report and initialize */
218	printk(KERN_INFO "NODE_DATA(%d) allocated [mem %#010Lx-%#010Lx]\n", nid,
219	       nd_pa, nd_pa + nd_size - 1);
220	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
221	if (tnid != nid)
222		printk(KERN_INFO "    NODE_DATA(%d) on node %d\n", nid, tnid);
223
224	node_data[nid] = nd;
225	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
226
227	node_set_online(nid);
228}
229
230/**
231 * numa_cleanup_meminfo - Cleanup a numa_meminfo
232 * @mi: numa_meminfo to clean up
233 *
234 * Sanitize @mi by merging and removing unnecessary memblks.  Also check for
235 * conflicts and clear unused memblks.
236 *
237 * RETURNS:
238 * 0 on success, -errno on failure.
239 */
240int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
241{
242	const u64 low = 0;
243	const u64 high = PFN_PHYS(max_pfn);
244	int i, j, k;
245
246	/* first, trim all entries */
247	for (i = 0; i < mi->nr_blks; i++) {
248		struct numa_memblk *bi = &mi->blk[i];
249
250		/* move / save reserved memory ranges */
251		if (!memblock_overlaps_region(&memblock.memory,
252					bi->start, bi->end - bi->start)) {
253			numa_move_tail_memblk(&numa_reserved_meminfo, i--, mi);
254			continue;
255		}
256
257		/* make sure all non-reserved blocks are inside the limits */
258		bi->start = max(bi->start, low);
259		bi->end = min(bi->end, high);
260
261		/* and there's no empty block */
262		if (bi->start >= bi->end)
263			numa_remove_memblk_from(i--, mi);
264	}
265
266	/* merge neighboring / overlapping entries */
267	for (i = 0; i < mi->nr_blks; i++) {
268		struct numa_memblk *bi = &mi->blk[i];
269
270		for (j = i + 1; j < mi->nr_blks; j++) {
271			struct numa_memblk *bj = &mi->blk[j];
272			u64 start, end;
273
274			/*
275			 * See whether there are overlapping blocks.  Whine
276			 * about but allow overlaps of the same nid.  They
277			 * will be merged below.
278			 */
279			if (bi->end > bj->start && bi->start < bj->end) {
280				if (bi->nid != bj->nid) {
281					pr_err("node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
282					       bi->nid, bi->start, bi->end - 1,
283					       bj->nid, bj->start, bj->end - 1);
284					return -EINVAL;
285				}
286				pr_warn("Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
287					bi->nid, bi->start, bi->end - 1,
288					bj->start, bj->end - 1);
289			}
290
291			/*
292			 * Join together blocks on the same node, holes
293			 * between which don't overlap with memory on other
294			 * nodes.
295			 */
296			if (bi->nid != bj->nid)
297				continue;
298			start = min(bi->start, bj->start);
299			end = max(bi->end, bj->end);
300			for (k = 0; k < mi->nr_blks; k++) {
301				struct numa_memblk *bk = &mi->blk[k];
302
303				if (bi->nid == bk->nid)
304					continue;
305				if (start < bk->end && end > bk->start)
306					break;
307			}
308			if (k < mi->nr_blks)
309				continue;
310			printk(KERN_INFO "NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
311			       bi->nid, bi->start, bi->end - 1, bj->start,
312			       bj->end - 1, start, end - 1);
313			bi->start = start;
314			bi->end = end;
315			numa_remove_memblk_from(j--, mi);
316		}
317	}
318
319	/* clear unused ones */
320	for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
321		mi->blk[i].start = mi->blk[i].end = 0;
322		mi->blk[i].nid = NUMA_NO_NODE;
323	}
324
325	return 0;
326}
327
328/*
329 * Set nodes, which have memory in @mi, in *@nodemask.
330 */
331static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
332					      const struct numa_meminfo *mi)
333{
334	int i;
335
336	for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
337		if (mi->blk[i].start != mi->blk[i].end &&
338		    mi->blk[i].nid != NUMA_NO_NODE)
339			node_set(mi->blk[i].nid, *nodemask);
340}
341
342/**
343 * numa_reset_distance - Reset NUMA distance table
344 *
345 * The current table is freed.  The next numa_set_distance() call will
346 * create a new one.
347 */
348void __init numa_reset_distance(void)
349{
350	size_t size = numa_distance_cnt * numa_distance_cnt * sizeof(numa_distance[0]);
351
352	/* numa_distance could be 1LU marking allocation failure, test cnt */
353	if (numa_distance_cnt)
354		memblock_free(__pa(numa_distance), size);
355	numa_distance_cnt = 0;
356	numa_distance = NULL;	/* enable table creation */
357}
358
359static int __init numa_alloc_distance(void)
360{
361	nodemask_t nodes_parsed;
362	size_t size;
363	int i, j, cnt = 0;
364	u64 phys;
365
366	/* size the new table and allocate it */
367	nodes_parsed = numa_nodes_parsed;
368	numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
369
370	for_each_node_mask(i, nodes_parsed)
371		cnt = i;
372	cnt++;
373	size = cnt * cnt * sizeof(numa_distance[0]);
374
375	phys = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
376				      size, PAGE_SIZE);
377	if (!phys) {
378		pr_warn("Warning: can't allocate distance table!\n");
379		/* don't retry until explicitly reset */
380		numa_distance = (void *)1LU;
381		return -ENOMEM;
382	}
383	memblock_reserve(phys, size);
384
385	numa_distance = __va(phys);
386	numa_distance_cnt = cnt;
387
388	/* fill with the default distances */
389	for (i = 0; i < cnt; i++)
390		for (j = 0; j < cnt; j++)
391			numa_distance[i * cnt + j] = i == j ?
392				LOCAL_DISTANCE : REMOTE_DISTANCE;
393	printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
394
395	return 0;
396}
397
398/**
399 * numa_set_distance - Set NUMA distance from one NUMA to another
400 * @from: the 'from' node to set distance
401 * @to: the 'to'  node to set distance
402 * @distance: NUMA distance
403 *
404 * Set the distance from node @from to @to to @distance.  If distance table
405 * doesn't exist, one which is large enough to accommodate all the currently
406 * known nodes will be created.
407 *
408 * If such table cannot be allocated, a warning is printed and further
409 * calls are ignored until the distance table is reset with
410 * numa_reset_distance().
411 *
412 * If @from or @to is higher than the highest known node or lower than zero
413 * at the time of table creation or @distance doesn't make sense, the call
414 * is ignored.
415 * This is to allow simplification of specific NUMA config implementations.
416 */
417void __init numa_set_distance(int from, int to, int distance)
418{
419	if (!numa_distance && numa_alloc_distance() < 0)
420		return;
421
422	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
423			from < 0 || to < 0) {
424		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
425			     from, to, distance);
426		return;
427	}
428
429	if ((u8)distance != distance ||
430	    (from == to && distance != LOCAL_DISTANCE)) {
431		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
432			     from, to, distance);
433		return;
434	}
435
436	numa_distance[from * numa_distance_cnt + to] = distance;
437}
438
439int __node_distance(int from, int to)
440{
441	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
442		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
443	return numa_distance[from * numa_distance_cnt + to];
444}
445EXPORT_SYMBOL(__node_distance);
446
447/*
448 * Sanity check to catch more bad NUMA configurations (they are amazingly
449 * common).  Make sure the nodes cover all memory.
450 */
451static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
452{
453	u64 numaram, e820ram;
454	int i;
455
456	numaram = 0;
457	for (i = 0; i < mi->nr_blks; i++) {
458		u64 s = mi->blk[i].start >> PAGE_SHIFT;
459		u64 e = mi->blk[i].end >> PAGE_SHIFT;
460		numaram += e - s;
461		numaram -= __absent_pages_in_range(mi->blk[i].nid, s, e);
462		if ((s64)numaram < 0)
463			numaram = 0;
464	}
465
466	e820ram = max_pfn - absent_pages_in_range(0, max_pfn);
467
468	/* We seem to lose 3 pages somewhere. Allow 1M of slack. */
469	if ((s64)(e820ram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
470		printk(KERN_ERR "NUMA: nodes only cover %LuMB of your %LuMB e820 RAM. Not used.\n",
471		       (numaram << PAGE_SHIFT) >> 20,
472		       (e820ram << PAGE_SHIFT) >> 20);
473		return false;
474	}
475	return true;
476}
477
478/*
479 * Mark all currently memblock-reserved physical memory (which covers the
480 * kernel's own memory ranges) as hot-unswappable.
481 */
482static void __init numa_clear_kernel_node_hotplug(void)
483{
484	nodemask_t reserved_nodemask = NODE_MASK_NONE;
485	struct memblock_region *mb_region;
486	int i;
487
488	/*
489	 * We have to do some preprocessing of memblock regions, to
490	 * make them suitable for reservation.
491	 *
492	 * At this time, all memory regions reserved by memblock are
493	 * used by the kernel, but those regions are not split up
494	 * along node boundaries yet, and don't necessarily have their
495	 * node ID set yet either.
496	 *
497	 * So iterate over all memory known to the x86 architecture,
498	 * and use those ranges to set the nid in memblock.reserved.
499	 * This will split up the memblock regions along node
500	 * boundaries and will set the node IDs as well.
501	 */
502	for (i = 0; i < numa_meminfo.nr_blks; i++) {
503		struct numa_memblk *mb = numa_meminfo.blk + i;
504		int ret;
505
506		ret = memblock_set_node(mb->start, mb->end - mb->start, &memblock.reserved, mb->nid);
507		WARN_ON_ONCE(ret);
508	}
509
510	/*
511	 * Now go over all reserved memblock regions, to construct a
512	 * node mask of all kernel reserved memory areas.
513	 *
514	 * [ Note, when booting with mem=nn[kMG] or in a kdump kernel,
515	 *   numa_meminfo might not include all memblock.reserved
516	 *   memory ranges, because quirks such as trim_snb_memory()
517	 *   reserve specific pages for Sandy Bridge graphics. ]
518	 */
519	for_each_memblock(reserved, mb_region) {
520		int nid = memblock_get_region_node(mb_region);
521
522		if (nid != MAX_NUMNODES)
523			node_set(nid, reserved_nodemask);
524	}
525
526	/*
527	 * Finally, clear the MEMBLOCK_HOTPLUG flag for all memory
528	 * belonging to the reserved node mask.
529	 *
530	 * Note that this will include memory regions that reside
531	 * on nodes that contain kernel memory - entire nodes
532	 * become hot-unpluggable:
533	 */
534	for (i = 0; i < numa_meminfo.nr_blks; i++) {
535		struct numa_memblk *mb = numa_meminfo.blk + i;
536
537		if (!node_isset(mb->nid, reserved_nodemask))
538			continue;
539
540		memblock_clear_hotplug(mb->start, mb->end - mb->start);
541	}
542}
543
544static int __init numa_register_memblks(struct numa_meminfo *mi)
545{
546	int i, nid;
547
548	/* Account for nodes with cpus and no memory */
549	node_possible_map = numa_nodes_parsed;
550	numa_nodemask_from_meminfo(&node_possible_map, mi);
551	if (WARN_ON(nodes_empty(node_possible_map)))
552		return -EINVAL;
553
554	for (i = 0; i < mi->nr_blks; i++) {
555		struct numa_memblk *mb = &mi->blk[i];
556		memblock_set_node(mb->start, mb->end - mb->start,
557				  &memblock.memory, mb->nid);
558	}
559
560	/*
561	 * At very early time, the kernel have to use some memory such as
562	 * loading the kernel image. We cannot prevent this anyway. So any
563	 * node the kernel resides in should be un-hotpluggable.
564	 *
565	 * And when we come here, alloc node data won't fail.
566	 */
567	numa_clear_kernel_node_hotplug();
568
569	/*
570	 * If sections array is gonna be used for pfn -> nid mapping, check
571	 * whether its granularity is fine enough.
572	 */
573	if (IS_ENABLED(NODE_NOT_IN_PAGE_FLAGS)) {
574		unsigned long pfn_align = node_map_pfn_alignment();
575
576		if (pfn_align && pfn_align < PAGES_PER_SECTION) {
577			pr_warn("Node alignment %LuMB < min %LuMB, rejecting NUMA config\n",
578				PFN_PHYS(pfn_align) >> 20,
579				PFN_PHYS(PAGES_PER_SECTION) >> 20);
580			return -EINVAL;
581		}
582	}
583	if (!numa_meminfo_cover_memory(mi))
584		return -EINVAL;
585
586	/* Finally register nodes. */
587	for_each_node_mask(nid, node_possible_map) {
588		u64 start = PFN_PHYS(max_pfn);
589		u64 end = 0;
590
591		for (i = 0; i < mi->nr_blks; i++) {
592			if (nid != mi->blk[i].nid)
593				continue;
594			start = min(mi->blk[i].start, start);
595			end = max(mi->blk[i].end, end);
596		}
597
598		if (start >= end)
599			continue;
600
601		/*
602		 * Don't confuse VM with a node that doesn't have the
603		 * minimum amount of memory:
604		 */
605		if (end && (end - start) < NODE_MIN_SIZE)
 
606			continue;
607
608		alloc_node_data(nid);
 
609	}
610
611	/* Dump memblock with node info and return. */
612	memblock_dump_all();
613	return 0;
614}
615
616/*
617 * There are unfortunately some poorly designed mainboards around that
618 * only connect memory to a single CPU. This breaks the 1:1 cpu->node
619 * mapping. To avoid this fill in the mapping for all possible CPUs,
620 * as the number of CPUs is not known yet. We round robin the existing
621 * nodes.
622 */
623static void __init numa_init_array(void)
624{
625	int rr, i;
626
627	rr = first_node(node_online_map);
628	for (i = 0; i < nr_cpu_ids; i++) {
629		if (early_cpu_to_node(i) != NUMA_NO_NODE)
630			continue;
631		numa_set_node(i, rr);
632		rr = next_node_in(rr, node_online_map);
633	}
634}
635
636static int __init numa_init(int (*init_func)(void))
637{
638	int i;
639	int ret;
640
641	for (i = 0; i < MAX_LOCAL_APIC; i++)
642		set_apicid_to_node(i, NUMA_NO_NODE);
643
644	nodes_clear(numa_nodes_parsed);
645	nodes_clear(node_possible_map);
646	nodes_clear(node_online_map);
647	memset(&numa_meminfo, 0, sizeof(numa_meminfo));
648	WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.memory,
649				  MAX_NUMNODES));
650	WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.reserved,
651				  MAX_NUMNODES));
652	/* In case that parsing SRAT failed. */
653	WARN_ON(memblock_clear_hotplug(0, ULLONG_MAX));
654	numa_reset_distance();
655
656	ret = init_func();
657	if (ret < 0)
658		return ret;
659
660	/*
661	 * We reset memblock back to the top-down direction
662	 * here because if we configured ACPI_NUMA, we have
663	 * parsed SRAT in init_func(). It is ok to have the
664	 * reset here even if we did't configure ACPI_NUMA
665	 * or acpi numa init fails and fallbacks to dummy
666	 * numa init.
667	 */
668	memblock_set_bottom_up(false);
669
670	ret = numa_cleanup_meminfo(&numa_meminfo);
671	if (ret < 0)
672		return ret;
673
674	numa_emulation(&numa_meminfo, numa_distance_cnt);
675
676	ret = numa_register_memblks(&numa_meminfo);
677	if (ret < 0)
678		return ret;
679
680	for (i = 0; i < nr_cpu_ids; i++) {
681		int nid = early_cpu_to_node(i);
682
683		if (nid == NUMA_NO_NODE)
684			continue;
685		if (!node_online(nid))
686			numa_clear_node(i);
687	}
688	numa_init_array();
689
690	return 0;
691}
692
693/**
694 * dummy_numa_init - Fallback dummy NUMA init
695 *
696 * Used if there's no underlying NUMA architecture, NUMA initialization
697 * fails, or NUMA is disabled on the command line.
698 *
699 * Must online at least one node and add memory blocks that cover all
700 * allowed memory.  This function must not fail.
701 */
702static int __init dummy_numa_init(void)
703{
704	printk(KERN_INFO "%s\n",
705	       numa_off ? "NUMA turned off" : "No NUMA configuration found");
706	printk(KERN_INFO "Faking a node at [mem %#018Lx-%#018Lx]\n",
707	       0LLU, PFN_PHYS(max_pfn) - 1);
708
709	node_set(0, numa_nodes_parsed);
710	numa_add_memblk(0, 0, PFN_PHYS(max_pfn));
711
712	return 0;
713}
714
715/**
716 * x86_numa_init - Initialize NUMA
717 *
718 * Try each configured NUMA initialization method until one succeeds.  The
719 * last fallback is dummy single node config encompassing whole memory and
720 * never fails.
721 */
722void __init x86_numa_init(void)
723{
724	if (!numa_off) {
725#ifdef CONFIG_ACPI_NUMA
726		if (!numa_init(x86_acpi_numa_init))
727			return;
728#endif
729#ifdef CONFIG_AMD_NUMA
730		if (!numa_init(amd_numa_init))
731			return;
732#endif
 
 
733	}
734
735	numa_init(dummy_numa_init);
736}
737
738static void __init init_memory_less_node(int nid)
 
 
 
 
 
 
 
 
 
 
 
 
 
739{
740	/* Allocate and initialize node data. Memory-less node is now online.*/
741	alloc_node_data(nid);
742	free_area_init_memoryless_node(nid);
743
744	/*
745	 * All zonelists will be built later in start_kernel() after per cpu
746	 * areas are initialized.
 
 
 
 
 
747	 */
 
 
 
748}
749
750/*
751 * Setup early cpu_to_node.
752 *
753 * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
754 * and apicid_to_node[] tables have valid entries for a CPU.
755 * This means we skip cpu_to_node[] initialisation for NUMA
756 * emulation and faking node case (when running a kernel compiled
757 * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
758 * is already initialized in a round robin manner at numa_init_array,
759 * prior to this call, and this initialization is good enough
760 * for the fake NUMA cases.
761 *
762 * Called before the per_cpu areas are setup.
763 */
764void __init init_cpu_to_node(void)
765{
766	int cpu;
767	u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
768
769	BUG_ON(cpu_to_apicid == NULL);
770
771	for_each_possible_cpu(cpu) {
772		int node = numa_cpu_node(cpu);
773
774		if (node == NUMA_NO_NODE)
775			continue;
776
 
 
 
 
 
 
 
 
 
777		if (!node_online(node))
778			init_memory_less_node(node);
779
780		numa_set_node(cpu, node);
781	}
782}
783
784#ifndef CONFIG_DEBUG_PER_CPU_MAPS
785
786# ifndef CONFIG_NUMA_EMU
787void numa_add_cpu(int cpu)
788{
789	cpumask_set_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
790}
791
792void numa_remove_cpu(int cpu)
793{
794	cpumask_clear_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
795}
796# endif	/* !CONFIG_NUMA_EMU */
797
798#else	/* !CONFIG_DEBUG_PER_CPU_MAPS */
799
800int __cpu_to_node(int cpu)
801{
802	if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
803		printk(KERN_WARNING
804			"cpu_to_node(%d): usage too early!\n", cpu);
805		dump_stack();
806		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
807	}
808	return per_cpu(x86_cpu_to_node_map, cpu);
809}
810EXPORT_SYMBOL(__cpu_to_node);
811
812/*
813 * Same function as cpu_to_node() but used if called before the
814 * per_cpu areas are setup.
815 */
816int early_cpu_to_node(int cpu)
817{
818	if (early_per_cpu_ptr(x86_cpu_to_node_map))
819		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
820
821	if (!cpu_possible(cpu)) {
822		printk(KERN_WARNING
823			"early_cpu_to_node(%d): no per_cpu area!\n", cpu);
824		dump_stack();
825		return NUMA_NO_NODE;
826	}
827	return per_cpu(x86_cpu_to_node_map, cpu);
828}
829
830void debug_cpumask_set_cpu(int cpu, int node, bool enable)
831{
832	struct cpumask *mask;
833
834	if (node == NUMA_NO_NODE) {
835		/* early_cpu_to_node() already emits a warning and trace */
836		return;
837	}
838	mask = node_to_cpumask_map[node];
839	if (!mask) {
840		pr_err("node_to_cpumask_map[%i] NULL\n", node);
841		dump_stack();
842		return;
843	}
844
845	if (enable)
846		cpumask_set_cpu(cpu, mask);
847	else
848		cpumask_clear_cpu(cpu, mask);
849
850	printk(KERN_DEBUG "%s cpu %d node %d: mask now %*pbl\n",
851		enable ? "numa_add_cpu" : "numa_remove_cpu",
852		cpu, node, cpumask_pr_args(mask));
853	return;
854}
855
856# ifndef CONFIG_NUMA_EMU
857static void numa_set_cpumask(int cpu, bool enable)
858{
859	debug_cpumask_set_cpu(cpu, early_cpu_to_node(cpu), enable);
860}
861
862void numa_add_cpu(int cpu)
863{
864	numa_set_cpumask(cpu, true);
865}
866
867void numa_remove_cpu(int cpu)
868{
869	numa_set_cpumask(cpu, false);
870}
871# endif	/* !CONFIG_NUMA_EMU */
872
873/*
874 * Returns a pointer to the bitmask of CPUs on Node 'node'.
875 */
876const struct cpumask *cpumask_of_node(int node)
877{
878	if ((unsigned)node >= nr_node_ids) {
879		printk(KERN_WARNING
880			"cpumask_of_node(%d): (unsigned)node >= nr_node_ids(%u)\n",
881			node, nr_node_ids);
882		dump_stack();
883		return cpu_none_mask;
884	}
885	if (node_to_cpumask_map[node] == NULL) {
886		printk(KERN_WARNING
887			"cpumask_of_node(%d): no node_to_cpumask_map!\n",
888			node);
889		dump_stack();
890		return cpu_online_mask;
891	}
892	return node_to_cpumask_map[node];
893}
894EXPORT_SYMBOL(cpumask_of_node);
895
896#endif	/* !CONFIG_DEBUG_PER_CPU_MAPS */
897
898#ifdef CONFIG_NUMA_KEEP_MEMINFO
899static int meminfo_to_nid(struct numa_meminfo *mi, u64 start)
900{
901	int i;
902
903	for (i = 0; i < mi->nr_blks; i++)
904		if (mi->blk[i].start <= start && mi->blk[i].end > start)
905			return mi->blk[i].nid;
906	return NUMA_NO_NODE;
907}
908
909int phys_to_target_node(phys_addr_t start)
910{
911	int nid = meminfo_to_nid(&numa_meminfo, start);
912
913	/*
914	 * Prefer online nodes, but if reserved memory might be
915	 * hot-added continue the search with reserved ranges.
 
916	 */
917	if (nid != NUMA_NO_NODE)
918		return nid;
919
920	return meminfo_to_nid(&numa_reserved_meminfo, start);
 
 
 
 
921}
922EXPORT_SYMBOL_GPL(phys_to_target_node);
923
924int memory_add_physaddr_to_nid(u64 start)
925{
926	int nid = meminfo_to_nid(&numa_meminfo, start);
927
928	if (nid == NUMA_NO_NODE)
929		nid = numa_meminfo.blk[0].nid;
930	return nid;
931}
932#endif