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7#include <linux/stddef.h>
8#include <linux/mm.h>
9#include <linux/swap.h>
10#include <linux/interrupt.h>
11#include <linux/pagemap.h>
12#include <linux/bootmem.h>
13#include <linux/compiler.h>
14#include <linux/export.h>
15#include <linux/pagevec.h>
16#include <linux/writeback.h>
17#include <linux/slab.h>
18#include <linux/sysctl.h>
19#include <linux/cpu.h>
20#include <linux/memory.h>
21#include <linux/memory_hotplug.h>
22#include <linux/highmem.h>
23#include <linux/vmalloc.h>
24#include <linux/ioport.h>
25#include <linux/delay.h>
26#include <linux/migrate.h>
27#include <linux/page-isolation.h>
28#include <linux/pfn.h>
29#include <linux/suspend.h>
30#include <linux/mm_inline.h>
31#include <linux/firmware-map.h>
32#include <linux/stop_machine.h>
33
34#include <asm/tlbflush.h>
35
36#include "internal.h"
37
38
39
40
41
42
43
44
45static void generic_online_page(struct page *page);
46
47static online_page_callback_t online_page_callback = generic_online_page;
48
49DEFINE_MUTEX(mem_hotplug_mutex);
50
51void lock_memory_hotplug(void)
52{
53 mutex_lock(&mem_hotplug_mutex);
54
55
56 lock_system_sleep();
57}
58
59void unlock_memory_hotplug(void)
60{
61 unlock_system_sleep();
62 mutex_unlock(&mem_hotplug_mutex);
63}
64
65
66
67static struct resource *register_memory_resource(u64 start, u64 size)
68{
69 struct resource *res;
70 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
71 BUG_ON(!res);
72
73 res->name = "System RAM";
74 res->start = start;
75 res->end = start + size - 1;
76 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
77 if (request_resource(&iomem_resource, res) < 0) {
78 pr_debug("System RAM resource %pR cannot be added\n", res);
79 kfree(res);
80 res = NULL;
81 }
82 return res;
83}
84
85static void release_memory_resource(struct resource *res)
86{
87 if (!res)
88 return;
89 release_resource(res);
90 kfree(res);
91 return;
92}
93
94#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
95void get_page_bootmem(unsigned long info, struct page *page,
96 unsigned long type)
97{
98 page->lru.next = (struct list_head *) type;
99 SetPagePrivate(page);
100 set_page_private(page, info);
101 atomic_inc(&page->_count);
102}
103
104void put_page_bootmem(struct page *page)
105{
106 unsigned long type;
107
108 type = (unsigned long) page->lru.next;
109 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
110 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
111
112 if (atomic_dec_return(&page->_count) == 1) {
113 ClearPagePrivate(page);
114 set_page_private(page, 0);
115 INIT_LIST_HEAD(&page->lru);
116 free_reserved_page(page);
117 }
118}
119
120#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
121#ifndef CONFIG_SPARSEMEM_VMEMMAP
122static void register_page_bootmem_info_section(unsigned long start_pfn)
123{
124 unsigned long *usemap, mapsize, section_nr, i;
125 struct mem_section *ms;
126 struct page *page, *memmap;
127
128 section_nr = pfn_to_section_nr(start_pfn);
129 ms = __nr_to_section(section_nr);
130
131
132 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
133
134
135
136
137
138 page = virt_to_page(memmap);
139 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
140 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
141
142
143 for (i = 0; i < mapsize; i++, page++)
144 get_page_bootmem(section_nr, page, SECTION_INFO);
145
146 usemap = __nr_to_section(section_nr)->pageblock_flags;
147 page = virt_to_page(usemap);
148
149 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
150
151 for (i = 0; i < mapsize; i++, page++)
152 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
153
154}
155#else
156static void register_page_bootmem_info_section(unsigned long start_pfn)
157{
158 unsigned long *usemap, mapsize, section_nr, i;
159 struct mem_section *ms;
160 struct page *page, *memmap;
161
162 if (!pfn_valid(start_pfn))
163 return;
164
165 section_nr = pfn_to_section_nr(start_pfn);
166 ms = __nr_to_section(section_nr);
167
168 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
169
170 register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
171
172 usemap = __nr_to_section(section_nr)->pageblock_flags;
173 page = virt_to_page(usemap);
174
175 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
176
177 for (i = 0; i < mapsize; i++, page++)
178 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
179}
180#endif
181
182void register_page_bootmem_info_node(struct pglist_data *pgdat)
183{
184 unsigned long i, pfn, end_pfn, nr_pages;
185 int node = pgdat->node_id;
186 struct page *page;
187 struct zone *zone;
188
189 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
190 page = virt_to_page(pgdat);
191
192 for (i = 0; i < nr_pages; i++, page++)
193 get_page_bootmem(node, page, NODE_INFO);
194
195 zone = &pgdat->node_zones[0];
196 for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
197 if (zone->wait_table) {
198 nr_pages = zone->wait_table_hash_nr_entries
199 * sizeof(wait_queue_head_t);
200 nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
201 page = virt_to_page(zone->wait_table);
202
203 for (i = 0; i < nr_pages; i++, page++)
204 get_page_bootmem(node, page, NODE_INFO);
205 }
206 }
207
208 pfn = pgdat->node_start_pfn;
209 end_pfn = pgdat_end_pfn(pgdat);
210
211
212 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
213
214
215
216
217
218
219 if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node))
220 register_page_bootmem_info_section(pfn);
221 }
222}
223#endif
224
225static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
226 unsigned long end_pfn)
227{
228 unsigned long old_zone_end_pfn;
229
230 zone_span_writelock(zone);
231
232 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
233 if (!zone->spanned_pages || start_pfn < zone->zone_start_pfn)
234 zone->zone_start_pfn = start_pfn;
235
236 zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
237 zone->zone_start_pfn;
238
239 zone_span_writeunlock(zone);
240}
241
242static void resize_zone(struct zone *zone, unsigned long start_pfn,
243 unsigned long end_pfn)
244{
245 zone_span_writelock(zone);
246
247 if (end_pfn - start_pfn) {
248 zone->zone_start_pfn = start_pfn;
249 zone->spanned_pages = end_pfn - start_pfn;
250 } else {
251
252
253
254
255 zone->zone_start_pfn = 0;
256 zone->spanned_pages = 0;
257 }
258
259 zone_span_writeunlock(zone);
260}
261
262static void fix_zone_id(struct zone *zone, unsigned long start_pfn,
263 unsigned long end_pfn)
264{
265 enum zone_type zid = zone_idx(zone);
266 int nid = zone->zone_pgdat->node_id;
267 unsigned long pfn;
268
269 for (pfn = start_pfn; pfn < end_pfn; pfn++)
270 set_page_links(pfn_to_page(pfn), zid, nid, pfn);
271}
272
273
274
275static int __ref ensure_zone_is_initialized(struct zone *zone,
276 unsigned long start_pfn, unsigned long num_pages)
277{
278 if (!zone_is_initialized(zone))
279 return init_currently_empty_zone(zone, start_pfn, num_pages,
280 MEMMAP_HOTPLUG);
281 return 0;
282}
283
284static int __meminit move_pfn_range_left(struct zone *z1, struct zone *z2,
285 unsigned long start_pfn, unsigned long end_pfn)
286{
287 int ret;
288 unsigned long flags;
289 unsigned long z1_start_pfn;
290
291 ret = ensure_zone_is_initialized(z1, start_pfn, end_pfn - start_pfn);
292 if (ret)
293 return ret;
294
295 pgdat_resize_lock(z1->zone_pgdat, &flags);
296
297
298 if (end_pfn > zone_end_pfn(z2))
299 goto out_fail;
300
301 if (start_pfn > z2->zone_start_pfn)
302 goto out_fail;
303
304 if (end_pfn <= z2->zone_start_pfn)
305 goto out_fail;
306
307
308 if (z1->spanned_pages)
309 z1_start_pfn = z1->zone_start_pfn;
310 else
311 z1_start_pfn = start_pfn;
312
313 resize_zone(z1, z1_start_pfn, end_pfn);
314 resize_zone(z2, end_pfn, zone_end_pfn(z2));
315
316 pgdat_resize_unlock(z1->zone_pgdat, &flags);
317
318 fix_zone_id(z1, start_pfn, end_pfn);
319
320 return 0;
321out_fail:
322 pgdat_resize_unlock(z1->zone_pgdat, &flags);
323 return -1;
324}
325
326static int __meminit move_pfn_range_right(struct zone *z1, struct zone *z2,
327 unsigned long start_pfn, unsigned long end_pfn)
328{
329 int ret;
330 unsigned long flags;
331 unsigned long z2_end_pfn;
332
333 ret = ensure_zone_is_initialized(z2, start_pfn, end_pfn - start_pfn);
334 if (ret)
335 return ret;
336
337 pgdat_resize_lock(z1->zone_pgdat, &flags);
338
339
340 if (z1->zone_start_pfn > start_pfn)
341 goto out_fail;
342
343 if (zone_end_pfn(z1) > end_pfn)
344 goto out_fail;
345
346 if (start_pfn >= zone_end_pfn(z1))
347 goto out_fail;
348
349
350 if (z2->spanned_pages)
351 z2_end_pfn = zone_end_pfn(z2);
352 else
353 z2_end_pfn = end_pfn;
354
355 resize_zone(z1, z1->zone_start_pfn, start_pfn);
356 resize_zone(z2, start_pfn, z2_end_pfn);
357
358 pgdat_resize_unlock(z1->zone_pgdat, &flags);
359
360 fix_zone_id(z2, start_pfn, end_pfn);
361
362 return 0;
363out_fail:
364 pgdat_resize_unlock(z1->zone_pgdat, &flags);
365 return -1;
366}
367
368static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
369 unsigned long end_pfn)
370{
371 unsigned long old_pgdat_end_pfn =
372 pgdat->node_start_pfn + pgdat->node_spanned_pages;
373
374 if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
375 pgdat->node_start_pfn = start_pfn;
376
377 pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
378 pgdat->node_start_pfn;
379}
380
381static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
382{
383 struct pglist_data *pgdat = zone->zone_pgdat;
384 int nr_pages = PAGES_PER_SECTION;
385 int nid = pgdat->node_id;
386 int zone_type;
387 unsigned long flags;
388 int ret;
389
390 zone_type = zone - pgdat->node_zones;
391 ret = ensure_zone_is_initialized(zone, phys_start_pfn, nr_pages);
392 if (ret)
393 return ret;
394
395 pgdat_resize_lock(zone->zone_pgdat, &flags);
396 grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
397 grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
398 phys_start_pfn + nr_pages);
399 pgdat_resize_unlock(zone->zone_pgdat, &flags);
400 memmap_init_zone(nr_pages, nid, zone_type,
401 phys_start_pfn, MEMMAP_HOTPLUG);
402 return 0;
403}
404
405static int __meminit __add_section(int nid, struct zone *zone,
406 unsigned long phys_start_pfn)
407{
408 int nr_pages = PAGES_PER_SECTION;
409 int ret;
410
411 if (pfn_valid(phys_start_pfn))
412 return -EEXIST;
413
414 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
415
416 if (ret < 0)
417 return ret;
418
419 ret = __add_zone(zone, phys_start_pfn);
420
421 if (ret < 0)
422 return ret;
423
424 return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
425}
426
427
428
429
430
431
432
433int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
434 unsigned long nr_pages)
435{
436 unsigned long i;
437 int err = 0;
438 int start_sec, end_sec;
439
440 start_sec = pfn_to_section_nr(phys_start_pfn);
441 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
442
443 for (i = start_sec; i <= end_sec; i++) {
444 err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
445
446
447
448
449
450
451 if (err && (err != -EEXIST))
452 break;
453 err = 0;
454 }
455
456 return err;
457}
458EXPORT_SYMBOL_GPL(__add_pages);
459
460#ifdef CONFIG_MEMORY_HOTREMOVE
461
462static int find_smallest_section_pfn(int nid, struct zone *zone,
463 unsigned long start_pfn,
464 unsigned long end_pfn)
465{
466 struct mem_section *ms;
467
468 for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
469 ms = __pfn_to_section(start_pfn);
470
471 if (unlikely(!valid_section(ms)))
472 continue;
473
474 if (unlikely(pfn_to_nid(start_pfn) != nid))
475 continue;
476
477 if (zone && zone != page_zone(pfn_to_page(start_pfn)))
478 continue;
479
480 return start_pfn;
481 }
482
483 return 0;
484}
485
486
487static int find_biggest_section_pfn(int nid, struct zone *zone,
488 unsigned long start_pfn,
489 unsigned long end_pfn)
490{
491 struct mem_section *ms;
492 unsigned long pfn;
493
494
495 pfn = end_pfn - 1;
496 for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
497 ms = __pfn_to_section(pfn);
498
499 if (unlikely(!valid_section(ms)))
500 continue;
501
502 if (unlikely(pfn_to_nid(pfn) != nid))
503 continue;
504
505 if (zone && zone != page_zone(pfn_to_page(pfn)))
506 continue;
507
508 return pfn;
509 }
510
511 return 0;
512}
513
514static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
515 unsigned long end_pfn)
516{
517 unsigned long zone_start_pfn = zone->zone_start_pfn;
518 unsigned long zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
519 unsigned long pfn;
520 struct mem_section *ms;
521 int nid = zone_to_nid(zone);
522
523 zone_span_writelock(zone);
524 if (zone_start_pfn == start_pfn) {
525
526
527
528
529
530
531 pfn = find_smallest_section_pfn(nid, zone, end_pfn,
532 zone_end_pfn);
533 if (pfn) {
534 zone->zone_start_pfn = pfn;
535 zone->spanned_pages = zone_end_pfn - pfn;
536 }
537 } else if (zone_end_pfn == end_pfn) {
538
539
540
541
542
543
544 pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
545 start_pfn);
546 if (pfn)
547 zone->spanned_pages = pfn - zone_start_pfn + 1;
548 }
549
550
551
552
553
554
555
556 pfn = zone_start_pfn;
557 for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
558 ms = __pfn_to_section(pfn);
559
560 if (unlikely(!valid_section(ms)))
561 continue;
562
563 if (page_zone(pfn_to_page(pfn)) != zone)
564 continue;
565
566
567 if (start_pfn == pfn)
568 continue;
569
570
571 zone_span_writeunlock(zone);
572 return;
573 }
574
575
576 zone->zone_start_pfn = 0;
577 zone->spanned_pages = 0;
578 zone_span_writeunlock(zone);
579}
580
581static void shrink_pgdat_span(struct pglist_data *pgdat,
582 unsigned long start_pfn, unsigned long end_pfn)
583{
584 unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
585 unsigned long pgdat_end_pfn =
586 pgdat->node_start_pfn + pgdat->node_spanned_pages;
587 unsigned long pfn;
588 struct mem_section *ms;
589 int nid = pgdat->node_id;
590
591 if (pgdat_start_pfn == start_pfn) {
592
593
594
595
596
597
598 pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
599 pgdat_end_pfn);
600 if (pfn) {
601 pgdat->node_start_pfn = pfn;
602 pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
603 }
604 } else if (pgdat_end_pfn == end_pfn) {
605
606
607
608
609
610
611 pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
612 start_pfn);
613 if (pfn)
614 pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
615 }
616
617
618
619
620
621
622
623
624 pfn = pgdat_start_pfn;
625 for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
626 ms = __pfn_to_section(pfn);
627
628 if (unlikely(!valid_section(ms)))
629 continue;
630
631 if (pfn_to_nid(pfn) != nid)
632 continue;
633
634
635 if (start_pfn == pfn)
636 continue;
637
638
639 return;
640 }
641
642
643 pgdat->node_start_pfn = 0;
644 pgdat->node_spanned_pages = 0;
645}
646
647static void __remove_zone(struct zone *zone, unsigned long start_pfn)
648{
649 struct pglist_data *pgdat = zone->zone_pgdat;
650 int nr_pages = PAGES_PER_SECTION;
651 int zone_type;
652 unsigned long flags;
653
654 zone_type = zone - pgdat->node_zones;
655
656 pgdat_resize_lock(zone->zone_pgdat, &flags);
657 shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
658 shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
659 pgdat_resize_unlock(zone->zone_pgdat, &flags);
660}
661
662static int __remove_section(struct zone *zone, struct mem_section *ms)
663{
664 unsigned long start_pfn;
665 int scn_nr;
666 int ret = -EINVAL;
667
668 if (!valid_section(ms))
669 return ret;
670
671 ret = unregister_memory_section(ms);
672 if (ret)
673 return ret;
674
675 scn_nr = __section_nr(ms);
676 start_pfn = section_nr_to_pfn(scn_nr);
677 __remove_zone(zone, start_pfn);
678
679 sparse_remove_one_section(zone, ms);
680 return 0;
681}
682
683
684
685
686
687
688
689
690
691
692
693
694int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
695 unsigned long nr_pages)
696{
697 unsigned long i;
698 int sections_to_remove;
699 resource_size_t start, size;
700 int ret = 0;
701
702
703
704
705 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
706 BUG_ON(nr_pages % PAGES_PER_SECTION);
707
708 start = phys_start_pfn << PAGE_SHIFT;
709 size = nr_pages * PAGE_SIZE;
710 ret = release_mem_region_adjustable(&iomem_resource, start, size);
711 if (ret) {
712 resource_size_t endres = start + size - 1;
713
714 pr_warn("Unable to release resource <%pa-%pa> (%d)\n",
715 &start, &endres, ret);
716 }
717
718 sections_to_remove = nr_pages / PAGES_PER_SECTION;
719 for (i = 0; i < sections_to_remove; i++) {
720 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
721 ret = __remove_section(zone, __pfn_to_section(pfn));
722 if (ret)
723 break;
724 }
725 return ret;
726}
727EXPORT_SYMBOL_GPL(__remove_pages);
728#endif
729
730int set_online_page_callback(online_page_callback_t callback)
731{
732 int rc = -EINVAL;
733
734 lock_memory_hotplug();
735
736 if (online_page_callback == generic_online_page) {
737 online_page_callback = callback;
738 rc = 0;
739 }
740
741 unlock_memory_hotplug();
742
743 return rc;
744}
745EXPORT_SYMBOL_GPL(set_online_page_callback);
746
747int restore_online_page_callback(online_page_callback_t callback)
748{
749 int rc = -EINVAL;
750
751 lock_memory_hotplug();
752
753 if (online_page_callback == callback) {
754 online_page_callback = generic_online_page;
755 rc = 0;
756 }
757
758 unlock_memory_hotplug();
759
760 return rc;
761}
762EXPORT_SYMBOL_GPL(restore_online_page_callback);
763
764void __online_page_set_limits(struct page *page)
765{
766}
767EXPORT_SYMBOL_GPL(__online_page_set_limits);
768
769void __online_page_increment_counters(struct page *page)
770{
771 adjust_managed_page_count(page, 1);
772}
773EXPORT_SYMBOL_GPL(__online_page_increment_counters);
774
775void __online_page_free(struct page *page)
776{
777 __free_reserved_page(page);
778}
779EXPORT_SYMBOL_GPL(__online_page_free);
780
781static void generic_online_page(struct page *page)
782{
783 __online_page_set_limits(page);
784 __online_page_increment_counters(page);
785 __online_page_free(page);
786}
787
788static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
789 void *arg)
790{
791 unsigned long i;
792 unsigned long onlined_pages = *(unsigned long *)arg;
793 struct page *page;
794 if (PageReserved(pfn_to_page(start_pfn)))
795 for (i = 0; i < nr_pages; i++) {
796 page = pfn_to_page(start_pfn + i);
797 (*online_page_callback)(page);
798 onlined_pages++;
799 }
800 *(unsigned long *)arg = onlined_pages;
801 return 0;
802}
803
804#ifdef CONFIG_MOVABLE_NODE
805
806
807
808
809static bool can_online_high_movable(struct zone *zone)
810{
811 return true;
812}
813#else
814
815static bool can_online_high_movable(struct zone *zone)
816{
817 return node_state(zone_to_nid(zone), N_NORMAL_MEMORY);
818}
819#endif
820
821
822static void node_states_check_changes_online(unsigned long nr_pages,
823 struct zone *zone, struct memory_notify *arg)
824{
825 int nid = zone_to_nid(zone);
826 enum zone_type zone_last = ZONE_NORMAL;
827
828
829
830
831
832
833
834
835
836
837 if (N_MEMORY == N_NORMAL_MEMORY)
838 zone_last = ZONE_MOVABLE;
839
840
841
842
843
844
845
846 if (zone_idx(zone) <= zone_last && !node_state(nid, N_NORMAL_MEMORY))
847 arg->status_change_nid_normal = nid;
848 else
849 arg->status_change_nid_normal = -1;
850
851#ifdef CONFIG_HIGHMEM
852
853
854
855
856
857
858
859
860
861 zone_last = ZONE_HIGHMEM;
862 if (N_MEMORY == N_HIGH_MEMORY)
863 zone_last = ZONE_MOVABLE;
864
865 if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
866 arg->status_change_nid_high = nid;
867 else
868 arg->status_change_nid_high = -1;
869#else
870 arg->status_change_nid_high = arg->status_change_nid_normal;
871#endif
872
873
874
875
876
877
878 if (!node_state(nid, N_MEMORY))
879 arg->status_change_nid = nid;
880 else
881 arg->status_change_nid = -1;
882}
883
884static void node_states_set_node(int node, struct memory_notify *arg)
885{
886 if (arg->status_change_nid_normal >= 0)
887 node_set_state(node, N_NORMAL_MEMORY);
888
889 if (arg->status_change_nid_high >= 0)
890 node_set_state(node, N_HIGH_MEMORY);
891
892 node_set_state(node, N_MEMORY);
893}
894
895
896int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
897{
898 unsigned long flags;
899 unsigned long onlined_pages = 0;
900 struct zone *zone;
901 int need_zonelists_rebuild = 0;
902 int nid;
903 int ret;
904 struct memory_notify arg;
905
906 lock_memory_hotplug();
907
908
909
910
911
912 zone = page_zone(pfn_to_page(pfn));
913
914 if ((zone_idx(zone) > ZONE_NORMAL || online_type == ONLINE_MOVABLE) &&
915 !can_online_high_movable(zone)) {
916 unlock_memory_hotplug();
917 return -EINVAL;
918 }
919
920 if (online_type == ONLINE_KERNEL && zone_idx(zone) == ZONE_MOVABLE) {
921 if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages)) {
922 unlock_memory_hotplug();
923 return -EINVAL;
924 }
925 }
926 if (online_type == ONLINE_MOVABLE && zone_idx(zone) == ZONE_MOVABLE - 1) {
927 if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages)) {
928 unlock_memory_hotplug();
929 return -EINVAL;
930 }
931 }
932
933
934 zone = page_zone(pfn_to_page(pfn));
935
936 arg.start_pfn = pfn;
937 arg.nr_pages = nr_pages;
938 node_states_check_changes_online(nr_pages, zone, &arg);
939
940 nid = page_to_nid(pfn_to_page(pfn));
941
942 ret = memory_notify(MEM_GOING_ONLINE, &arg);
943 ret = notifier_to_errno(ret);
944 if (ret) {
945 memory_notify(MEM_CANCEL_ONLINE, &arg);
946 unlock_memory_hotplug();
947 return ret;
948 }
949
950
951
952
953
954 mutex_lock(&zonelists_mutex);
955 if (!populated_zone(zone)) {
956 need_zonelists_rebuild = 1;
957 build_all_zonelists(NULL, zone);
958 }
959
960 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
961 online_pages_range);
962 if (ret) {
963 if (need_zonelists_rebuild)
964 zone_pcp_reset(zone);
965 mutex_unlock(&zonelists_mutex);
966 printk(KERN_DEBUG "online_pages [mem %#010llx-%#010llx] failed\n",
967 (unsigned long long) pfn << PAGE_SHIFT,
968 (((unsigned long long) pfn + nr_pages)
969 << PAGE_SHIFT) - 1);
970 memory_notify(MEM_CANCEL_ONLINE, &arg);
971 unlock_memory_hotplug();
972 return ret;
973 }
974
975 zone->present_pages += onlined_pages;
976
977 pgdat_resize_lock(zone->zone_pgdat, &flags);
978 zone->zone_pgdat->node_present_pages += onlined_pages;
979 pgdat_resize_unlock(zone->zone_pgdat, &flags);
980
981 if (onlined_pages) {
982 node_states_set_node(zone_to_nid(zone), &arg);
983 if (need_zonelists_rebuild)
984 build_all_zonelists(NULL, NULL);
985 else
986 zone_pcp_update(zone);
987 }
988
989 mutex_unlock(&zonelists_mutex);
990
991 init_per_zone_wmark_min();
992
993 if (onlined_pages)
994 kswapd_run(zone_to_nid(zone));
995
996 vm_total_pages = nr_free_pagecache_pages();
997
998 writeback_set_ratelimit();
999
1000 if (onlined_pages)
1001 memory_notify(MEM_ONLINE, &arg);
1002 unlock_memory_hotplug();
1003
1004 return 0;
1005}
1006#endif
1007
1008
1009static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
1010{
1011 struct pglist_data *pgdat;
1012 unsigned long zones_size[MAX_NR_ZONES] = {0};
1013 unsigned long zholes_size[MAX_NR_ZONES] = {0};
1014 unsigned long start_pfn = start >> PAGE_SHIFT;
1015
1016 pgdat = NODE_DATA(nid);
1017 if (!pgdat) {
1018 pgdat = arch_alloc_nodedata(nid);
1019 if (!pgdat)
1020 return NULL;
1021
1022 arch_refresh_nodedata(nid, pgdat);
1023 }
1024
1025
1026
1027
1028 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
1029
1030
1031
1032
1033
1034 mutex_lock(&zonelists_mutex);
1035 build_all_zonelists(pgdat, NULL);
1036 mutex_unlock(&zonelists_mutex);
1037
1038 return pgdat;
1039}
1040
1041static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
1042{
1043 arch_refresh_nodedata(nid, NULL);
1044 arch_free_nodedata(pgdat);
1045 return;
1046}
1047
1048
1049
1050
1051
1052int mem_online_node(int nid)
1053{
1054 pg_data_t *pgdat;
1055 int ret;
1056
1057 lock_memory_hotplug();
1058 pgdat = hotadd_new_pgdat(nid, 0);
1059 if (!pgdat) {
1060 ret = -ENOMEM;
1061 goto out;
1062 }
1063 node_set_online(nid);
1064 ret = register_one_node(nid);
1065 BUG_ON(ret);
1066
1067out:
1068 unlock_memory_hotplug();
1069 return ret;
1070}
1071
1072
1073int __ref add_memory(int nid, u64 start, u64 size)
1074{
1075 pg_data_t *pgdat = NULL;
1076 bool new_pgdat;
1077 bool new_node;
1078 struct resource *res;
1079 int ret;
1080
1081 lock_memory_hotplug();
1082
1083 res = register_memory_resource(start, size);
1084 ret = -EEXIST;
1085 if (!res)
1086 goto out;
1087
1088 {
1089 void *p = NODE_DATA(nid);
1090 new_pgdat = !p;
1091 }
1092 new_node = !node_online(nid);
1093 if (new_node) {
1094 pgdat = hotadd_new_pgdat(nid, start);
1095 ret = -ENOMEM;
1096 if (!pgdat)
1097 goto error;
1098 }
1099
1100
1101 ret = arch_add_memory(nid, start, size);
1102
1103 if (ret < 0)
1104 goto error;
1105
1106
1107 node_set_online(nid);
1108
1109 if (new_node) {
1110 ret = register_one_node(nid);
1111
1112
1113
1114
1115
1116 BUG_ON(ret);
1117 }
1118
1119
1120 firmware_map_add_hotplug(start, start + size, "System RAM");
1121
1122 goto out;
1123
1124error:
1125
1126 if (new_pgdat)
1127 rollback_node_hotadd(nid, pgdat);
1128 release_memory_resource(res);
1129
1130out:
1131 unlock_memory_hotplug();
1132 return ret;
1133}
1134EXPORT_SYMBOL_GPL(add_memory);
1135
1136#ifdef CONFIG_MEMORY_HOTREMOVE
1137
1138
1139
1140
1141
1142
1143
1144static inline int pageblock_free(struct page *page)
1145{
1146 return PageBuddy(page) && page_order(page) >= pageblock_order;
1147}
1148
1149
1150static struct page *next_active_pageblock(struct page *page)
1151{
1152
1153 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
1154
1155
1156 if (pageblock_free(page)) {
1157 int order;
1158
1159 order = page_order(page);
1160 if ((order < MAX_ORDER) && (order >= pageblock_order))
1161 return page + (1 << order);
1162 }
1163
1164 return page + pageblock_nr_pages;
1165}
1166
1167
1168int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
1169{
1170 struct page *page = pfn_to_page(start_pfn);
1171 struct page *end_page = page + nr_pages;
1172
1173
1174 for (; page < end_page; page = next_active_pageblock(page)) {
1175 if (!is_pageblock_removable_nolock(page))
1176 return 0;
1177 cond_resched();
1178 }
1179
1180
1181 return 1;
1182}
1183
1184
1185
1186
1187static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
1188{
1189 unsigned long pfn;
1190 struct zone *zone = NULL;
1191 struct page *page;
1192 int i;
1193 for (pfn = start_pfn;
1194 pfn < end_pfn;
1195 pfn += MAX_ORDER_NR_PAGES) {
1196 i = 0;
1197
1198 while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i))
1199 i++;
1200 if (i == MAX_ORDER_NR_PAGES)
1201 continue;
1202 page = pfn_to_page(pfn + i);
1203 if (zone && page_zone(page) != zone)
1204 return 0;
1205 zone = page_zone(page);
1206 }
1207 return 1;
1208}
1209
1210
1211
1212
1213
1214static unsigned long scan_lru_pages(unsigned long start, unsigned long end)
1215{
1216 unsigned long pfn;
1217 struct page *page;
1218 for (pfn = start; pfn < end; pfn++) {
1219 if (pfn_valid(pfn)) {
1220 page = pfn_to_page(pfn);
1221 if (PageLRU(page))
1222 return pfn;
1223 }
1224 }
1225 return 0;
1226}
1227
1228#define NR_OFFLINE_AT_ONCE_PAGES (256)
1229static int
1230do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
1231{
1232 unsigned long pfn;
1233 struct page *page;
1234 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
1235 int not_managed = 0;
1236 int ret = 0;
1237 LIST_HEAD(source);
1238
1239 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
1240 if (!pfn_valid(pfn))
1241 continue;
1242 page = pfn_to_page(pfn);
1243 if (!get_page_unless_zero(page))
1244 continue;
1245
1246
1247
1248
1249 ret = isolate_lru_page(page);
1250 if (!ret) {
1251 put_page(page);
1252 list_add_tail(&page->lru, &source);
1253 move_pages--;
1254 inc_zone_page_state(page, NR_ISOLATED_ANON +
1255 page_is_file_cache(page));
1256
1257 } else {
1258#ifdef CONFIG_DEBUG_VM
1259 printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
1260 pfn);
1261 dump_page(page);
1262#endif
1263 put_page(page);
1264
1265
1266 if (page_count(page)) {
1267 not_managed++;
1268 ret = -EBUSY;
1269 break;
1270 }
1271 }
1272 }
1273 if (!list_empty(&source)) {
1274 if (not_managed) {
1275 putback_lru_pages(&source);
1276 goto out;
1277 }
1278
1279
1280
1281
1282
1283 ret = migrate_pages(&source, alloc_migrate_target, 0,
1284 MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
1285 if (ret)
1286 putback_lru_pages(&source);
1287 }
1288out:
1289 return ret;
1290}
1291
1292
1293
1294
1295static int
1296offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
1297 void *data)
1298{
1299 __offline_isolated_pages(start, start + nr_pages);
1300 return 0;
1301}
1302
1303static void
1304offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
1305{
1306 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
1307 offline_isolated_pages_cb);
1308}
1309
1310
1311
1312
1313static int
1314check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
1315 void *data)
1316{
1317 int ret;
1318 long offlined = *(long *)data;
1319 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
1320 offlined = nr_pages;
1321 if (!ret)
1322 *(long *)data += offlined;
1323 return ret;
1324}
1325
1326static long
1327check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
1328{
1329 long offlined = 0;
1330 int ret;
1331
1332 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
1333 check_pages_isolated_cb);
1334 if (ret < 0)
1335 offlined = (long)ret;
1336 return offlined;
1337}
1338
1339#ifdef CONFIG_MOVABLE_NODE
1340
1341
1342
1343
1344static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1345{
1346 return true;
1347}
1348#else
1349
1350static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1351{
1352 struct pglist_data *pgdat = zone->zone_pgdat;
1353 unsigned long present_pages = 0;
1354 enum zone_type zt;
1355
1356 for (zt = 0; zt <= ZONE_NORMAL; zt++)
1357 present_pages += pgdat->node_zones[zt].present_pages;
1358
1359 if (present_pages > nr_pages)
1360 return true;
1361
1362 present_pages = 0;
1363 for (; zt <= ZONE_MOVABLE; zt++)
1364 present_pages += pgdat->node_zones[zt].present_pages;
1365
1366
1367
1368
1369
1370 return present_pages == 0;
1371}
1372#endif
1373
1374
1375static void node_states_check_changes_offline(unsigned long nr_pages,
1376 struct zone *zone, struct memory_notify *arg)
1377{
1378 struct pglist_data *pgdat = zone->zone_pgdat;
1379 unsigned long present_pages = 0;
1380 enum zone_type zt, zone_last = ZONE_NORMAL;
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391 if (N_MEMORY == N_NORMAL_MEMORY)
1392 zone_last = ZONE_MOVABLE;
1393
1394
1395
1396
1397
1398
1399
1400
1401 for (zt = 0; zt <= zone_last; zt++)
1402 present_pages += pgdat->node_zones[zt].present_pages;
1403 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1404 arg->status_change_nid_normal = zone_to_nid(zone);
1405 else
1406 arg->status_change_nid_normal = -1;
1407
1408#ifdef CONFIG_HIGHMEM
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418 zone_last = ZONE_HIGHMEM;
1419 if (N_MEMORY == N_HIGH_MEMORY)
1420 zone_last = ZONE_MOVABLE;
1421
1422 for (; zt <= zone_last; zt++)
1423 present_pages += pgdat->node_zones[zt].present_pages;
1424 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1425 arg->status_change_nid_high = zone_to_nid(zone);
1426 else
1427 arg->status_change_nid_high = -1;
1428#else
1429 arg->status_change_nid_high = arg->status_change_nid_normal;
1430#endif
1431
1432
1433
1434
1435 zone_last = ZONE_MOVABLE;
1436
1437
1438
1439
1440
1441
1442
1443 for (; zt <= zone_last; zt++)
1444 present_pages += pgdat->node_zones[zt].present_pages;
1445 if (nr_pages >= present_pages)
1446 arg->status_change_nid = zone_to_nid(zone);
1447 else
1448 arg->status_change_nid = -1;
1449}
1450
1451static void node_states_clear_node(int node, struct memory_notify *arg)
1452{
1453 if (arg->status_change_nid_normal >= 0)
1454 node_clear_state(node, N_NORMAL_MEMORY);
1455
1456 if ((N_MEMORY != N_NORMAL_MEMORY) &&
1457 (arg->status_change_nid_high >= 0))
1458 node_clear_state(node, N_HIGH_MEMORY);
1459
1460 if ((N_MEMORY != N_HIGH_MEMORY) &&
1461 (arg->status_change_nid >= 0))
1462 node_clear_state(node, N_MEMORY);
1463}
1464
1465static int __ref __offline_pages(unsigned long start_pfn,
1466 unsigned long end_pfn, unsigned long timeout)
1467{
1468 unsigned long pfn, nr_pages, expire;
1469 long offlined_pages;
1470 int ret, drain, retry_max, node;
1471 unsigned long flags;
1472 struct zone *zone;
1473 struct memory_notify arg;
1474
1475 BUG_ON(start_pfn >= end_pfn);
1476
1477 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
1478 return -EINVAL;
1479 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
1480 return -EINVAL;
1481
1482
1483 if (!test_pages_in_a_zone(start_pfn, end_pfn))
1484 return -EINVAL;
1485
1486 lock_memory_hotplug();
1487
1488 zone = page_zone(pfn_to_page(start_pfn));
1489 node = zone_to_nid(zone);
1490 nr_pages = end_pfn - start_pfn;
1491
1492 ret = -EINVAL;
1493 if (zone_idx(zone) <= ZONE_NORMAL && !can_offline_normal(zone, nr_pages))
1494 goto out;
1495
1496
1497 ret = start_isolate_page_range(start_pfn, end_pfn,
1498 MIGRATE_MOVABLE, true);
1499 if (ret)
1500 goto out;
1501
1502 arg.start_pfn = start_pfn;
1503 arg.nr_pages = nr_pages;
1504 node_states_check_changes_offline(nr_pages, zone, &arg);
1505
1506 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
1507 ret = notifier_to_errno(ret);
1508 if (ret)
1509 goto failed_removal;
1510
1511 pfn = start_pfn;
1512 expire = jiffies + timeout;
1513 drain = 0;
1514 retry_max = 5;
1515repeat:
1516
1517 ret = -EAGAIN;
1518 if (time_after(jiffies, expire))
1519 goto failed_removal;
1520 ret = -EINTR;
1521 if (signal_pending(current))
1522 goto failed_removal;
1523 ret = 0;
1524 if (drain) {
1525 lru_add_drain_all();
1526 cond_resched();
1527 drain_all_pages();
1528 }
1529
1530 pfn = scan_lru_pages(start_pfn, end_pfn);
1531 if (pfn) {
1532 ret = do_migrate_range(pfn, end_pfn);
1533 if (!ret) {
1534 drain = 1;
1535 goto repeat;
1536 } else {
1537 if (ret < 0)
1538 if (--retry_max == 0)
1539 goto failed_removal;
1540 yield();
1541 drain = 1;
1542 goto repeat;
1543 }
1544 }
1545
1546 lru_add_drain_all();
1547 yield();
1548
1549 drain_all_pages();
1550
1551 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
1552 if (offlined_pages < 0) {
1553 ret = -EBUSY;
1554 goto failed_removal;
1555 }
1556 printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
1557
1558
1559 offline_isolated_pages(start_pfn, end_pfn);
1560
1561 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1562
1563 adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
1564 zone->present_pages -= offlined_pages;
1565
1566 pgdat_resize_lock(zone->zone_pgdat, &flags);
1567 zone->zone_pgdat->node_present_pages -= offlined_pages;
1568 pgdat_resize_unlock(zone->zone_pgdat, &flags);
1569
1570 init_per_zone_wmark_min();
1571
1572 if (!populated_zone(zone)) {
1573 zone_pcp_reset(zone);
1574 mutex_lock(&zonelists_mutex);
1575 build_all_zonelists(NULL, NULL);
1576 mutex_unlock(&zonelists_mutex);
1577 } else
1578 zone_pcp_update(zone);
1579
1580 node_states_clear_node(node, &arg);
1581 if (arg.status_change_nid >= 0)
1582 kswapd_stop(node);
1583
1584 vm_total_pages = nr_free_pagecache_pages();
1585 writeback_set_ratelimit();
1586
1587 memory_notify(MEM_OFFLINE, &arg);
1588 unlock_memory_hotplug();
1589 return 0;
1590
1591failed_removal:
1592 printk(KERN_INFO "memory offlining [mem %#010llx-%#010llx] failed\n",
1593 (unsigned long long) start_pfn << PAGE_SHIFT,
1594 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
1595 memory_notify(MEM_CANCEL_OFFLINE, &arg);
1596
1597 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1598
1599out:
1600 unlock_memory_hotplug();
1601 return ret;
1602}
1603
1604int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
1605{
1606 return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
1607}
1608#endif
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
1623 void *arg, int (*func)(struct memory_block *, void *))
1624{
1625 struct memory_block *mem = NULL;
1626 struct mem_section *section;
1627 unsigned long pfn, section_nr;
1628 int ret;
1629
1630 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1631 section_nr = pfn_to_section_nr(pfn);
1632 if (!present_section_nr(section_nr))
1633 continue;
1634
1635 section = __nr_to_section(section_nr);
1636
1637 if (mem)
1638 if ((section_nr >= mem->start_section_nr) &&
1639 (section_nr <= mem->end_section_nr))
1640 continue;
1641
1642 mem = find_memory_block_hinted(section, mem);
1643 if (!mem)
1644 continue;
1645
1646 ret = func(mem, arg);
1647 if (ret) {
1648 kobject_put(&mem->dev.kobj);
1649 return ret;
1650 }
1651 }
1652
1653 if (mem)
1654 kobject_put(&mem->dev.kobj);
1655
1656 return 0;
1657}
1658
1659#ifdef CONFIG_MEMORY_HOTREMOVE
1660static int is_memblock_offlined_cb(struct memory_block *mem, void *arg)
1661{
1662 int ret = !is_memblock_offlined(mem);
1663
1664 if (unlikely(ret)) {
1665 phys_addr_t beginpa, endpa;
1666
1667 beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr));
1668 endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1;
1669 pr_warn("removing memory fails, because memory "
1670 "[%pa-%pa] is onlined\n",
1671 &beginpa, &endpa);
1672 }
1673
1674 return ret;
1675}
1676
1677static int check_cpu_on_node(void *data)
1678{
1679 struct pglist_data *pgdat = data;
1680 int cpu;
1681
1682 for_each_present_cpu(cpu) {
1683 if (cpu_to_node(cpu) == pgdat->node_id)
1684
1685
1686
1687
1688 return -EBUSY;
1689 }
1690
1691 return 0;
1692}
1693
1694static void unmap_cpu_on_node(void *data)
1695{
1696#ifdef CONFIG_ACPI_NUMA
1697 struct pglist_data *pgdat = data;
1698 int cpu;
1699
1700 for_each_possible_cpu(cpu)
1701 if (cpu_to_node(cpu) == pgdat->node_id)
1702 numa_clear_node(cpu);
1703#endif
1704}
1705
1706static int check_and_unmap_cpu_on_node(void *data)
1707{
1708 int ret = check_cpu_on_node(data);
1709
1710 if (ret)
1711 return ret;
1712
1713
1714
1715
1716
1717
1718 unmap_cpu_on_node(data);
1719 return 0;
1720}
1721
1722
1723void try_offline_node(int nid)
1724{
1725 pg_data_t *pgdat = NODE_DATA(nid);
1726 unsigned long start_pfn = pgdat->node_start_pfn;
1727 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
1728 unsigned long pfn;
1729 struct page *pgdat_page = virt_to_page(pgdat);
1730 int i;
1731
1732 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1733 unsigned long section_nr = pfn_to_section_nr(pfn);
1734
1735 if (!present_section_nr(section_nr))
1736 continue;
1737
1738 if (pfn_to_nid(pfn) != nid)
1739 continue;
1740
1741
1742
1743
1744
1745 return;
1746 }
1747
1748 if (stop_machine(check_and_unmap_cpu_on_node, pgdat, NULL))
1749 return;
1750
1751
1752
1753
1754
1755 node_set_offline(nid);
1756 unregister_one_node(nid);
1757
1758 if (!PageSlab(pgdat_page) && !PageCompound(pgdat_page))
1759
1760 return;
1761
1762
1763 for (i = 0; i < MAX_NR_ZONES; i++) {
1764 struct zone *zone = pgdat->node_zones + i;
1765
1766
1767
1768
1769
1770 if (is_vmalloc_addr(zone->wait_table))
1771 vfree(zone->wait_table);
1772 }
1773
1774
1775
1776
1777
1778
1779
1780
1781 memset(pgdat, 0, sizeof(*pgdat));
1782}
1783EXPORT_SYMBOL(try_offline_node);
1784
1785void __ref remove_memory(int nid, u64 start, u64 size)
1786{
1787 int ret;
1788
1789 lock_memory_hotplug();
1790
1791
1792
1793
1794
1795
1796 ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
1797 is_memblock_offlined_cb);
1798 if (ret) {
1799 unlock_memory_hotplug();
1800 BUG();
1801 }
1802
1803
1804 firmware_map_remove(start, start + size, "System RAM");
1805
1806 arch_remove_memory(start, size);
1807
1808 try_offline_node(nid);
1809
1810 unlock_memory_hotplug();
1811}
1812EXPORT_SYMBOL_GPL(remove_memory);
1813#endif
1814