xref: /linux/arch/x86/mm/numa_64.c (revision 33619f0d3ff715a2a5499520967d526ad931d70d)
1 /*
2  * Generic VM initialization for x86-64 NUMA setups.
3  * Copyright 2002,2003 Andi Kleen, SuSE Labs.
4  */
5 #include <linux/kernel.h>
6 #include <linux/mm.h>
7 #include <linux/string.h>
8 #include <linux/init.h>
9 #include <linux/bootmem.h>
10 #include <linux/memblock.h>
11 #include <linux/mmzone.h>
12 #include <linux/ctype.h>
13 #include <linux/module.h>
14 #include <linux/nodemask.h>
15 #include <linux/sched.h>
16 
17 #include <asm/e820.h>
18 #include <asm/proto.h>
19 #include <asm/dma.h>
20 #include <asm/numa.h>
21 #include <asm/acpi.h>
22 #include <asm/amd_nb.h>
23 
24 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
25 EXPORT_SYMBOL(node_data);
26 
27 struct memnode memnode;
28 
29 s16 apicid_to_node[MAX_LOCAL_APIC] __cpuinitdata = {
30 	[0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
31 };
32 
33 static unsigned long __initdata nodemap_addr;
34 static unsigned long __initdata nodemap_size;
35 
36 /*
37  * Map cpu index to node index
38  */
39 DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
40 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
41 
42 /*
43  * Given a shift value, try to populate memnodemap[]
44  * Returns :
45  * 1 if OK
46  * 0 if memnodmap[] too small (of shift too small)
47  * -1 if node overlap or lost ram (shift too big)
48  */
49 static int __init populate_memnodemap(const struct bootnode *nodes,
50 				      int numnodes, int shift, int *nodeids)
51 {
52 	unsigned long addr, end;
53 	int i, res = -1;
54 
55 	memset(memnodemap, 0xff, sizeof(s16)*memnodemapsize);
56 	for (i = 0; i < numnodes; i++) {
57 		addr = nodes[i].start;
58 		end = nodes[i].end;
59 		if (addr >= end)
60 			continue;
61 		if ((end >> shift) >= memnodemapsize)
62 			return 0;
63 		do {
64 			if (memnodemap[addr >> shift] != NUMA_NO_NODE)
65 				return -1;
66 
67 			if (!nodeids)
68 				memnodemap[addr >> shift] = i;
69 			else
70 				memnodemap[addr >> shift] = nodeids[i];
71 
72 			addr += (1UL << shift);
73 		} while (addr < end);
74 		res = 1;
75 	}
76 	return res;
77 }
78 
79 static int __init allocate_cachealigned_memnodemap(void)
80 {
81 	unsigned long addr;
82 
83 	memnodemap = memnode.embedded_map;
84 	if (memnodemapsize <= ARRAY_SIZE(memnode.embedded_map))
85 		return 0;
86 
87 	addr = 0x8000;
88 	nodemap_size = roundup(sizeof(s16) * memnodemapsize, L1_CACHE_BYTES);
89 	nodemap_addr = memblock_find_in_range(addr, max_pfn<<PAGE_SHIFT,
90 				      nodemap_size, L1_CACHE_BYTES);
91 	if (nodemap_addr == MEMBLOCK_ERROR) {
92 		printk(KERN_ERR
93 		       "NUMA: Unable to allocate Memory to Node hash map\n");
94 		nodemap_addr = nodemap_size = 0;
95 		return -1;
96 	}
97 	memnodemap = phys_to_virt(nodemap_addr);
98 	memblock_x86_reserve_range(nodemap_addr, nodemap_addr + nodemap_size, "MEMNODEMAP");
99 
100 	printk(KERN_DEBUG "NUMA: Allocated memnodemap from %lx - %lx\n",
101 	       nodemap_addr, nodemap_addr + nodemap_size);
102 	return 0;
103 }
104 
105 /*
106  * The LSB of all start and end addresses in the node map is the value of the
107  * maximum possible shift.
108  */
109 static int __init extract_lsb_from_nodes(const struct bootnode *nodes,
110 					 int numnodes)
111 {
112 	int i, nodes_used = 0;
113 	unsigned long start, end;
114 	unsigned long bitfield = 0, memtop = 0;
115 
116 	for (i = 0; i < numnodes; i++) {
117 		start = nodes[i].start;
118 		end = nodes[i].end;
119 		if (start >= end)
120 			continue;
121 		bitfield |= start;
122 		nodes_used++;
123 		if (end > memtop)
124 			memtop = end;
125 	}
126 	if (nodes_used <= 1)
127 		i = 63;
128 	else
129 		i = find_first_bit(&bitfield, sizeof(unsigned long)*8);
130 	memnodemapsize = (memtop >> i)+1;
131 	return i;
132 }
133 
134 int __init compute_hash_shift(struct bootnode *nodes, int numnodes,
135 			      int *nodeids)
136 {
137 	int shift;
138 
139 	shift = extract_lsb_from_nodes(nodes, numnodes);
140 	if (allocate_cachealigned_memnodemap())
141 		return -1;
142 	printk(KERN_DEBUG "NUMA: Using %d for the hash shift.\n",
143 		shift);
144 
145 	if (populate_memnodemap(nodes, numnodes, shift, nodeids) != 1) {
146 		printk(KERN_INFO "Your memory is not aligned you need to "
147 		       "rebuild your kernel with a bigger NODEMAPSIZE "
148 		       "shift=%d\n", shift);
149 		return -1;
150 	}
151 	return shift;
152 }
153 
154 int __meminit  __early_pfn_to_nid(unsigned long pfn)
155 {
156 	return phys_to_nid(pfn << PAGE_SHIFT);
157 }
158 
159 static void * __init early_node_mem(int nodeid, unsigned long start,
160 				    unsigned long end, unsigned long size,
161 				    unsigned long align)
162 {
163 	unsigned long mem;
164 
165 	/*
166 	 * put it on high as possible
167 	 * something will go with NODE_DATA
168 	 */
169 	if (start < (MAX_DMA_PFN<<PAGE_SHIFT))
170 		start = MAX_DMA_PFN<<PAGE_SHIFT;
171 	if (start < (MAX_DMA32_PFN<<PAGE_SHIFT) &&
172 	    end > (MAX_DMA32_PFN<<PAGE_SHIFT))
173 		start = MAX_DMA32_PFN<<PAGE_SHIFT;
174 	mem = memblock_x86_find_in_range_node(nodeid, start, end, size, align);
175 	if (mem != MEMBLOCK_ERROR)
176 		return __va(mem);
177 
178 	/* extend the search scope */
179 	end = max_pfn_mapped << PAGE_SHIFT;
180 	start = MAX_DMA_PFN << PAGE_SHIFT;
181 	mem = memblock_find_in_range(start, end, size, align);
182 	if (mem != MEMBLOCK_ERROR)
183 		return __va(mem);
184 
185 	printk(KERN_ERR "Cannot find %lu bytes in node %d\n",
186 		       size, nodeid);
187 
188 	return NULL;
189 }
190 
191 /* Initialize bootmem allocator for a node */
192 void __init
193 setup_node_bootmem(int nodeid, unsigned long start, unsigned long end)
194 {
195 	unsigned long start_pfn, last_pfn, nodedata_phys;
196 	const int pgdat_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
197 	int nid;
198 
199 	if (!end)
200 		return;
201 
202 	/*
203 	 * Don't confuse VM with a node that doesn't have the
204 	 * minimum amount of memory:
205 	 */
206 	if (end && (end - start) < NODE_MIN_SIZE)
207 		return;
208 
209 	start = roundup(start, ZONE_ALIGN);
210 
211 	printk(KERN_INFO "Initmem setup node %d %016lx-%016lx\n", nodeid,
212 	       start, end);
213 
214 	start_pfn = start >> PAGE_SHIFT;
215 	last_pfn = end >> PAGE_SHIFT;
216 
217 	node_data[nodeid] = early_node_mem(nodeid, start, end, pgdat_size,
218 					   SMP_CACHE_BYTES);
219 	if (node_data[nodeid] == NULL)
220 		return;
221 	nodedata_phys = __pa(node_data[nodeid]);
222 	memblock_x86_reserve_range(nodedata_phys, nodedata_phys + pgdat_size, "NODE_DATA");
223 	printk(KERN_INFO "  NODE_DATA [%016lx - %016lx]\n", nodedata_phys,
224 		nodedata_phys + pgdat_size - 1);
225 	nid = phys_to_nid(nodedata_phys);
226 	if (nid != nodeid)
227 		printk(KERN_INFO "    NODE_DATA(%d) on node %d\n", nodeid, nid);
228 
229 	memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
230 	NODE_DATA(nodeid)->node_id = nodeid;
231 	NODE_DATA(nodeid)->node_start_pfn = start_pfn;
232 	NODE_DATA(nodeid)->node_spanned_pages = last_pfn - start_pfn;
233 
234 	node_set_online(nodeid);
235 }
236 
237 /*
238  * There are unfortunately some poorly designed mainboards around that
239  * only connect memory to a single CPU. This breaks the 1:1 cpu->node
240  * mapping. To avoid this fill in the mapping for all possible CPUs,
241  * as the number of CPUs is not known yet. We round robin the existing
242  * nodes.
243  */
244 void __init numa_init_array(void)
245 {
246 	int rr, i;
247 
248 	rr = first_node(node_online_map);
249 	for (i = 0; i < nr_cpu_ids; i++) {
250 		if (early_cpu_to_node(i) != NUMA_NO_NODE)
251 			continue;
252 		numa_set_node(i, rr);
253 		rr = next_node(rr, node_online_map);
254 		if (rr == MAX_NUMNODES)
255 			rr = first_node(node_online_map);
256 	}
257 }
258 
259 #ifdef CONFIG_NUMA_EMU
260 /* Numa emulation */
261 static struct bootnode nodes[MAX_NUMNODES] __initdata;
262 static struct bootnode physnodes[MAX_NUMNODES] __cpuinitdata;
263 static char *cmdline __initdata;
264 
265 void __init numa_emu_cmdline(char *str)
266 {
267 	cmdline = str;
268 }
269 
270 static int __init setup_physnodes(unsigned long start, unsigned long end,
271 					int acpi, int amd)
272 {
273 	int ret = 0;
274 	int i;
275 
276 	memset(physnodes, 0, sizeof(physnodes));
277 #ifdef CONFIG_ACPI_NUMA
278 	if (acpi)
279 		acpi_get_nodes(physnodes, start, end);
280 #endif
281 #ifdef CONFIG_AMD_NUMA
282 	if (amd)
283 		amd_get_nodes(physnodes);
284 #endif
285 	/*
286 	 * Basic sanity checking on the physical node map: there may be errors
287 	 * if the SRAT or AMD code incorrectly reported the topology or the mem=
288 	 * kernel parameter is used.
289 	 */
290 	for (i = 0; i < MAX_NUMNODES; i++) {
291 		if (physnodes[i].start == physnodes[i].end)
292 			continue;
293 		if (physnodes[i].start > end) {
294 			physnodes[i].end = physnodes[i].start;
295 			continue;
296 		}
297 		if (physnodes[i].end < start) {
298 			physnodes[i].start = physnodes[i].end;
299 			continue;
300 		}
301 		if (physnodes[i].start < start)
302 			physnodes[i].start = start;
303 		if (physnodes[i].end > end)
304 			physnodes[i].end = end;
305 		ret++;
306 	}
307 
308 	/*
309 	 * If no physical topology was detected, a single node is faked to cover
310 	 * the entire address space.
311 	 */
312 	if (!ret) {
313 		physnodes[ret].start = start;
314 		physnodes[ret].end = end;
315 		ret = 1;
316 	}
317 	return ret;
318 }
319 
320 static void __init fake_physnodes(int acpi, int amd, int nr_nodes)
321 {
322 	int i;
323 
324 	BUG_ON(acpi && amd);
325 #ifdef CONFIG_ACPI_NUMA
326 	if (acpi)
327 		acpi_fake_nodes(nodes, nr_nodes);
328 #endif
329 #ifdef CONFIG_AMD_NUMA
330 	if (amd)
331 		amd_fake_nodes(nodes, nr_nodes);
332 #endif
333 	if (!acpi && !amd)
334 		for (i = 0; i < nr_cpu_ids; i++)
335 			numa_set_node(i, 0);
336 }
337 
338 /*
339  * Setups up nid to range from addr to addr + size.  If the end
340  * boundary is greater than max_addr, then max_addr is used instead.
341  * The return value is 0 if there is additional memory left for
342  * allocation past addr and -1 otherwise.  addr is adjusted to be at
343  * the end of the node.
344  */
345 static int __init setup_node_range(int nid, u64 *addr, u64 size, u64 max_addr)
346 {
347 	int ret = 0;
348 	nodes[nid].start = *addr;
349 	*addr += size;
350 	if (*addr >= max_addr) {
351 		*addr = max_addr;
352 		ret = -1;
353 	}
354 	nodes[nid].end = *addr;
355 	node_set(nid, node_possible_map);
356 	printk(KERN_INFO "Faking node %d at %016Lx-%016Lx (%LuMB)\n", nid,
357 	       nodes[nid].start, nodes[nid].end,
358 	       (nodes[nid].end - nodes[nid].start) >> 20);
359 	return ret;
360 }
361 
362 /*
363  * Sets up nr_nodes fake nodes interleaved over physical nodes ranging from addr
364  * to max_addr.  The return value is the number of nodes allocated.
365  */
366 static int __init split_nodes_interleave(u64 addr, u64 max_addr, int nr_nodes)
367 {
368 	nodemask_t physnode_mask = NODE_MASK_NONE;
369 	u64 size;
370 	int big;
371 	int ret = 0;
372 	int i;
373 
374 	if (nr_nodes <= 0)
375 		return -1;
376 	if (nr_nodes > MAX_NUMNODES) {
377 		pr_info("numa=fake=%d too large, reducing to %d\n",
378 			nr_nodes, MAX_NUMNODES);
379 		nr_nodes = MAX_NUMNODES;
380 	}
381 
382 	size = (max_addr - addr - memblock_x86_hole_size(addr, max_addr)) / nr_nodes;
383 	/*
384 	 * Calculate the number of big nodes that can be allocated as a result
385 	 * of consolidating the remainder.
386 	 */
387 	big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * nr_nodes) /
388 		FAKE_NODE_MIN_SIZE;
389 
390 	size &= FAKE_NODE_MIN_HASH_MASK;
391 	if (!size) {
392 		pr_err("Not enough memory for each node.  "
393 			"NUMA emulation disabled.\n");
394 		return -1;
395 	}
396 
397 	for (i = 0; i < MAX_NUMNODES; i++)
398 		if (physnodes[i].start != physnodes[i].end)
399 			node_set(i, physnode_mask);
400 
401 	/*
402 	 * Continue to fill physical nodes with fake nodes until there is no
403 	 * memory left on any of them.
404 	 */
405 	while (nodes_weight(physnode_mask)) {
406 		for_each_node_mask(i, physnode_mask) {
407 			u64 end = physnodes[i].start + size;
408 			u64 dma32_end = PFN_PHYS(MAX_DMA32_PFN);
409 
410 			if (ret < big)
411 				end += FAKE_NODE_MIN_SIZE;
412 
413 			/*
414 			 * Continue to add memory to this fake node if its
415 			 * non-reserved memory is less than the per-node size.
416 			 */
417 			while (end - physnodes[i].start -
418 				memblock_x86_hole_size(physnodes[i].start, end) < size) {
419 				end += FAKE_NODE_MIN_SIZE;
420 				if (end > physnodes[i].end) {
421 					end = physnodes[i].end;
422 					break;
423 				}
424 			}
425 
426 			/*
427 			 * If there won't be at least FAKE_NODE_MIN_SIZE of
428 			 * non-reserved memory in ZONE_DMA32 for the next node,
429 			 * this one must extend to the boundary.
430 			 */
431 			if (end < dma32_end && dma32_end - end -
432 			    memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
433 				end = dma32_end;
434 
435 			/*
436 			 * If there won't be enough non-reserved memory for the
437 			 * next node, this one must extend to the end of the
438 			 * physical node.
439 			 */
440 			if (physnodes[i].end - end -
441 			    memblock_x86_hole_size(end, physnodes[i].end) < size)
442 				end = physnodes[i].end;
443 
444 			/*
445 			 * Avoid allocating more nodes than requested, which can
446 			 * happen as a result of rounding down each node's size
447 			 * to FAKE_NODE_MIN_SIZE.
448 			 */
449 			if (nodes_weight(physnode_mask) + ret >= nr_nodes)
450 				end = physnodes[i].end;
451 
452 			if (setup_node_range(ret++, &physnodes[i].start,
453 						end - physnodes[i].start,
454 						physnodes[i].end) < 0)
455 				node_clear(i, physnode_mask);
456 		}
457 	}
458 	return ret;
459 }
460 
461 /*
462  * Returns the end address of a node so that there is at least `size' amount of
463  * non-reserved memory or `max_addr' is reached.
464  */
465 static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
466 {
467 	u64 end = start + size;
468 
469 	while (end - start - memblock_x86_hole_size(start, end) < size) {
470 		end += FAKE_NODE_MIN_SIZE;
471 		if (end > max_addr) {
472 			end = max_addr;
473 			break;
474 		}
475 	}
476 	return end;
477 }
478 
479 /*
480  * Sets up fake nodes of `size' interleaved over physical nodes ranging from
481  * `addr' to `max_addr'.  The return value is the number of nodes allocated.
482  */
483 static int __init split_nodes_size_interleave(u64 addr, u64 max_addr, u64 size)
484 {
485 	nodemask_t physnode_mask = NODE_MASK_NONE;
486 	u64 min_size;
487 	int ret = 0;
488 	int i;
489 
490 	if (!size)
491 		return -1;
492 	/*
493 	 * The limit on emulated nodes is MAX_NUMNODES, so the size per node is
494 	 * increased accordingly if the requested size is too small.  This
495 	 * creates a uniform distribution of node sizes across the entire
496 	 * machine (but not necessarily over physical nodes).
497 	 */
498 	min_size = (max_addr - addr - memblock_x86_hole_size(addr, max_addr)) /
499 						MAX_NUMNODES;
500 	min_size = max(min_size, FAKE_NODE_MIN_SIZE);
501 	if ((min_size & FAKE_NODE_MIN_HASH_MASK) < min_size)
502 		min_size = (min_size + FAKE_NODE_MIN_SIZE) &
503 						FAKE_NODE_MIN_HASH_MASK;
504 	if (size < min_size) {
505 		pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
506 			size >> 20, min_size >> 20);
507 		size = min_size;
508 	}
509 	size &= FAKE_NODE_MIN_HASH_MASK;
510 
511 	for (i = 0; i < MAX_NUMNODES; i++)
512 		if (physnodes[i].start != physnodes[i].end)
513 			node_set(i, physnode_mask);
514 	/*
515 	 * Fill physical nodes with fake nodes of size until there is no memory
516 	 * left on any of them.
517 	 */
518 	while (nodes_weight(physnode_mask)) {
519 		for_each_node_mask(i, physnode_mask) {
520 			u64 dma32_end = MAX_DMA32_PFN << PAGE_SHIFT;
521 			u64 end;
522 
523 			end = find_end_of_node(physnodes[i].start,
524 						physnodes[i].end, size);
525 			/*
526 			 * If there won't be at least FAKE_NODE_MIN_SIZE of
527 			 * non-reserved memory in ZONE_DMA32 for the next node,
528 			 * this one must extend to the boundary.
529 			 */
530 			if (end < dma32_end && dma32_end - end -
531 			    memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
532 				end = dma32_end;
533 
534 			/*
535 			 * If there won't be enough non-reserved memory for the
536 			 * next node, this one must extend to the end of the
537 			 * physical node.
538 			 */
539 			if (physnodes[i].end - end -
540 			    memblock_x86_hole_size(end, physnodes[i].end) < size)
541 				end = physnodes[i].end;
542 
543 			/*
544 			 * Setup the fake node that will be allocated as bootmem
545 			 * later.  If setup_node_range() returns non-zero, there
546 			 * is no more memory available on this physical node.
547 			 */
548 			if (setup_node_range(ret++, &physnodes[i].start,
549 						end - physnodes[i].start,
550 						physnodes[i].end) < 0)
551 				node_clear(i, physnode_mask);
552 		}
553 	}
554 	return ret;
555 }
556 
557 /*
558  * Sets up the system RAM area from start_pfn to last_pfn according to the
559  * numa=fake command-line option.
560  */
561 static int __init numa_emulation(unsigned long start_pfn,
562 			unsigned long last_pfn, int acpi, int amd)
563 {
564 	u64 addr = start_pfn << PAGE_SHIFT;
565 	u64 max_addr = last_pfn << PAGE_SHIFT;
566 	int num_nodes;
567 	int i;
568 
569 	/*
570 	 * If the numa=fake command-line contains a 'M' or 'G', it represents
571 	 * the fixed node size.  Otherwise, if it is just a single number N,
572 	 * split the system RAM into N fake nodes.
573 	 */
574 	if (strchr(cmdline, 'M') || strchr(cmdline, 'G')) {
575 		u64 size;
576 
577 		size = memparse(cmdline, &cmdline);
578 		num_nodes = split_nodes_size_interleave(addr, max_addr, size);
579 	} else {
580 		unsigned long n;
581 
582 		n = simple_strtoul(cmdline, NULL, 0);
583 		num_nodes = split_nodes_interleave(addr, max_addr, n);
584 	}
585 
586 	if (num_nodes < 0)
587 		return num_nodes;
588 	memnode_shift = compute_hash_shift(nodes, num_nodes, NULL);
589 	if (memnode_shift < 0) {
590 		memnode_shift = 0;
591 		printk(KERN_ERR "No NUMA hash function found.  NUMA emulation "
592 		       "disabled.\n");
593 		return -1;
594 	}
595 
596 	/*
597 	 * We need to vacate all active ranges that may have been registered for
598 	 * the e820 memory map.
599 	 */
600 	remove_all_active_ranges();
601 	for_each_node_mask(i, node_possible_map) {
602 		memblock_x86_register_active_regions(i, nodes[i].start >> PAGE_SHIFT,
603 						nodes[i].end >> PAGE_SHIFT);
604 		setup_node_bootmem(i, nodes[i].start, nodes[i].end);
605 	}
606 	setup_physnodes(addr, max_addr, acpi, amd);
607 	fake_physnodes(acpi, amd, num_nodes);
608 	numa_init_array();
609 	return 0;
610 }
611 #endif /* CONFIG_NUMA_EMU */
612 
613 void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn,
614 				int acpi, int amd)
615 {
616 	int i;
617 
618 	nodes_clear(node_possible_map);
619 	nodes_clear(node_online_map);
620 
621 #ifdef CONFIG_NUMA_EMU
622 	setup_physnodes(start_pfn << PAGE_SHIFT, last_pfn << PAGE_SHIFT,
623 			acpi, amd);
624 	if (cmdline && !numa_emulation(start_pfn, last_pfn, acpi, amd))
625 		return;
626 	setup_physnodes(start_pfn << PAGE_SHIFT, last_pfn << PAGE_SHIFT,
627 			acpi, amd);
628 	nodes_clear(node_possible_map);
629 	nodes_clear(node_online_map);
630 #endif
631 
632 #ifdef CONFIG_ACPI_NUMA
633 	if (!numa_off && acpi && !acpi_scan_nodes(start_pfn << PAGE_SHIFT,
634 						  last_pfn << PAGE_SHIFT))
635 		return;
636 	nodes_clear(node_possible_map);
637 	nodes_clear(node_online_map);
638 #endif
639 
640 #ifdef CONFIG_AMD_NUMA
641 	if (!numa_off && amd && !amd_scan_nodes())
642 		return;
643 	nodes_clear(node_possible_map);
644 	nodes_clear(node_online_map);
645 #endif
646 	printk(KERN_INFO "%s\n",
647 	       numa_off ? "NUMA turned off" : "No NUMA configuration found");
648 
649 	printk(KERN_INFO "Faking a node at %016lx-%016lx\n",
650 	       start_pfn << PAGE_SHIFT,
651 	       last_pfn << PAGE_SHIFT);
652 	/* setup dummy node covering all memory */
653 	memnode_shift = 63;
654 	memnodemap = memnode.embedded_map;
655 	memnodemap[0] = 0;
656 	node_set_online(0);
657 	node_set(0, node_possible_map);
658 	for (i = 0; i < nr_cpu_ids; i++)
659 		numa_set_node(i, 0);
660 	memblock_x86_register_active_regions(0, start_pfn, last_pfn);
661 	setup_node_bootmem(0, start_pfn << PAGE_SHIFT, last_pfn << PAGE_SHIFT);
662 }
663 
664 unsigned long __init numa_free_all_bootmem(void)
665 {
666 	unsigned long pages = 0;
667 	int i;
668 
669 	for_each_online_node(i)
670 		pages += free_all_bootmem_node(NODE_DATA(i));
671 
672 	pages += free_all_memory_core_early(MAX_NUMNODES);
673 
674 	return pages;
675 }
676 
677 #ifdef CONFIG_NUMA
678 
679 static __init int find_near_online_node(int node)
680 {
681 	int n, val;
682 	int min_val = INT_MAX;
683 	int best_node = -1;
684 
685 	for_each_online_node(n) {
686 		val = node_distance(node, n);
687 
688 		if (val < min_val) {
689 			min_val = val;
690 			best_node = n;
691 		}
692 	}
693 
694 	return best_node;
695 }
696 
697 /*
698  * Setup early cpu_to_node.
699  *
700  * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
701  * and apicid_to_node[] tables have valid entries for a CPU.
702  * This means we skip cpu_to_node[] initialisation for NUMA
703  * emulation and faking node case (when running a kernel compiled
704  * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
705  * is already initialized in a round robin manner at numa_init_array,
706  * prior to this call, and this initialization is good enough
707  * for the fake NUMA cases.
708  *
709  * Called before the per_cpu areas are setup.
710  */
711 void __init init_cpu_to_node(void)
712 {
713 	int cpu;
714 	u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
715 
716 	BUG_ON(cpu_to_apicid == NULL);
717 
718 	for_each_possible_cpu(cpu) {
719 		int node;
720 		u16 apicid = cpu_to_apicid[cpu];
721 
722 		if (apicid == BAD_APICID)
723 			continue;
724 		node = apicid_to_node[apicid];
725 		if (node == NUMA_NO_NODE)
726 			continue;
727 		if (!node_online(node))
728 			node = find_near_online_node(node);
729 		numa_set_node(cpu, node);
730 	}
731 }
732 #endif
733 
734 
735 void __cpuinit numa_set_node(int cpu, int node)
736 {
737 	int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
738 
739 	/* early setting, no percpu area yet */
740 	if (cpu_to_node_map) {
741 		cpu_to_node_map[cpu] = node;
742 		return;
743 	}
744 
745 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
746 	if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
747 		printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
748 		dump_stack();
749 		return;
750 	}
751 #endif
752 	per_cpu(x86_cpu_to_node_map, cpu) = node;
753 
754 	if (node != NUMA_NO_NODE)
755 		set_cpu_numa_node(cpu, node);
756 }
757 
758 void __cpuinit numa_clear_node(int cpu)
759 {
760 	numa_set_node(cpu, NUMA_NO_NODE);
761 }
762 
763 #ifndef CONFIG_DEBUG_PER_CPU_MAPS
764 
765 #ifndef CONFIG_NUMA_EMU
766 void __cpuinit numa_add_cpu(int cpu)
767 {
768 	cpumask_set_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
769 }
770 
771 void __cpuinit numa_remove_cpu(int cpu)
772 {
773 	cpumask_clear_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
774 }
775 #else
776 void __cpuinit numa_add_cpu(int cpu)
777 {
778 	unsigned long addr;
779 	u16 apicid;
780 	int physnid;
781 	int nid = NUMA_NO_NODE;
782 
783 	apicid = early_per_cpu(x86_cpu_to_apicid, cpu);
784 	if (apicid != BAD_APICID)
785 		nid = apicid_to_node[apicid];
786 	if (nid == NUMA_NO_NODE)
787 		nid = early_cpu_to_node(cpu);
788 	BUG_ON(nid == NUMA_NO_NODE || !node_online(nid));
789 
790 	/*
791 	 * Use the starting address of the emulated node to find which physical
792 	 * node it is allocated on.
793 	 */
794 	addr = node_start_pfn(nid) << PAGE_SHIFT;
795 	for (physnid = 0; physnid < MAX_NUMNODES; physnid++)
796 		if (addr >= physnodes[physnid].start &&
797 		    addr < physnodes[physnid].end)
798 			break;
799 
800 	/*
801 	 * Map the cpu to each emulated node that is allocated on the physical
802 	 * node of the cpu's apic id.
803 	 */
804 	for_each_online_node(nid) {
805 		addr = node_start_pfn(nid) << PAGE_SHIFT;
806 		if (addr >= physnodes[physnid].start &&
807 		    addr < physnodes[physnid].end)
808 			cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
809 	}
810 }
811 
812 void __cpuinit numa_remove_cpu(int cpu)
813 {
814 	int i;
815 
816 	for_each_online_node(i)
817 		cpumask_clear_cpu(cpu, node_to_cpumask_map[i]);
818 }
819 #endif /* !CONFIG_NUMA_EMU */
820 
821 #else /* CONFIG_DEBUG_PER_CPU_MAPS */
822 static struct cpumask __cpuinit *debug_cpumask_set_cpu(int cpu, int enable)
823 {
824 	int node = early_cpu_to_node(cpu);
825 	struct cpumask *mask;
826 	char buf[64];
827 
828 	mask = node_to_cpumask_map[node];
829 	if (!mask) {
830 		pr_err("node_to_cpumask_map[%i] NULL\n", node);
831 		dump_stack();
832 		return NULL;
833 	}
834 
835 	cpulist_scnprintf(buf, sizeof(buf), mask);
836 	printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
837 		enable ? "numa_add_cpu" : "numa_remove_cpu",
838 		cpu, node, buf);
839 	return mask;
840 }
841 
842 /*
843  * --------- debug versions of the numa functions ---------
844  */
845 #ifndef CONFIG_NUMA_EMU
846 static void __cpuinit numa_set_cpumask(int cpu, int enable)
847 {
848 	struct cpumask *mask;
849 
850 	mask = debug_cpumask_set_cpu(cpu, enable);
851 	if (!mask)
852 		return;
853 
854 	if (enable)
855 		cpumask_set_cpu(cpu, mask);
856 	else
857 		cpumask_clear_cpu(cpu, mask);
858 }
859 #else
860 static void __cpuinit numa_set_cpumask(int cpu, int enable)
861 {
862 	int node = early_cpu_to_node(cpu);
863 	struct cpumask *mask;
864 	int i;
865 
866 	for_each_online_node(i) {
867 		unsigned long addr;
868 
869 		addr = node_start_pfn(i) << PAGE_SHIFT;
870 		if (addr < physnodes[node].start ||
871 					addr >= physnodes[node].end)
872 			continue;
873 		mask = debug_cpumask_set_cpu(cpu, enable);
874 		if (!mask)
875 			return;
876 
877 		if (enable)
878 			cpumask_set_cpu(cpu, mask);
879 		else
880 			cpumask_clear_cpu(cpu, mask);
881 	}
882 }
883 #endif /* CONFIG_NUMA_EMU */
884 
885 void __cpuinit numa_add_cpu(int cpu)
886 {
887 	numa_set_cpumask(cpu, 1);
888 }
889 
890 void __cpuinit numa_remove_cpu(int cpu)
891 {
892 	numa_set_cpumask(cpu, 0);
893 }
894 
895 int __cpu_to_node(int cpu)
896 {
897 	if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
898 		printk(KERN_WARNING
899 			"cpu_to_node(%d): usage too early!\n", cpu);
900 		dump_stack();
901 		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
902 	}
903 	return per_cpu(x86_cpu_to_node_map, cpu);
904 }
905 EXPORT_SYMBOL(__cpu_to_node);
906 
907 /*
908  * Same function as cpu_to_node() but used if called before the
909  * per_cpu areas are setup.
910  */
911 int early_cpu_to_node(int cpu)
912 {
913 	if (early_per_cpu_ptr(x86_cpu_to_node_map))
914 		return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
915 
916 	if (!cpu_possible(cpu)) {
917 		printk(KERN_WARNING
918 			"early_cpu_to_node(%d): no per_cpu area!\n", cpu);
919 		dump_stack();
920 		return NUMA_NO_NODE;
921 	}
922 	return per_cpu(x86_cpu_to_node_map, cpu);
923 }
924 
925 /*
926  * --------- end of debug versions of the numa functions ---------
927  */
928 
929 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
930