1
2
3
4
5
6
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/module.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
33#include <asm/tlbflush.h>
34
35#include "internal.h"
36
37DEFINE_MUTEX(mem_hotplug_mutex);
38
39void lock_memory_hotplug(void)
40{
41 mutex_lock(&mem_hotplug_mutex);
42
43
44 lock_system_sleep();
45}
46
47void unlock_memory_hotplug(void)
48{
49 unlock_system_sleep();
50 mutex_unlock(&mem_hotplug_mutex);
51}
52
53
54
55static struct resource *register_memory_resource(u64 start, u64 size)
56{
57 struct resource *res;
58 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
59 BUG_ON(!res);
60
61 res->name = "System RAM";
62 res->start = start;
63 res->end = start + size - 1;
64 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
65 if (request_resource(&iomem_resource, res) < 0) {
66 printk("System RAM resource %llx - %llx cannot be added\n",
67 (unsigned long long)res->start, (unsigned long long)res->end);
68 kfree(res);
69 res = NULL;
70 }
71 return res;
72}
73
74static void release_memory_resource(struct resource *res)
75{
76 if (!res)
77 return;
78 release_resource(res);
79 kfree(res);
80 return;
81}
82
83#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
84#ifndef CONFIG_SPARSEMEM_VMEMMAP
85static void get_page_bootmem(unsigned long info, struct page *page,
86 unsigned long type)
87{
88 page->lru.next = (struct list_head *) type;
89 SetPagePrivate(page);
90 set_page_private(page, info);
91 atomic_inc(&page->_count);
92}
93
94
95
96void __ref put_page_bootmem(struct page *page)
97{
98 unsigned long type;
99
100 type = (unsigned long) page->lru.next;
101 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
102 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
103
104 if (atomic_dec_return(&page->_count) == 1) {
105 ClearPagePrivate(page);
106 set_page_private(page, 0);
107 INIT_LIST_HEAD(&page->lru);
108 __free_pages_bootmem(page, 0);
109 }
110
111}
112
113static void register_page_bootmem_info_section(unsigned long start_pfn)
114{
115 unsigned long *usemap, mapsize, section_nr, i;
116 struct mem_section *ms;
117 struct page *page, *memmap;
118
119 if (!pfn_valid(start_pfn))
120 return;
121
122 section_nr = pfn_to_section_nr(start_pfn);
123 ms = __nr_to_section(section_nr);
124
125
126 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
127
128
129
130
131
132 page = virt_to_page(memmap);
133 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
134 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
135
136
137 for (i = 0; i < mapsize; i++, page++)
138 get_page_bootmem(section_nr, page, SECTION_INFO);
139
140 usemap = __nr_to_section(section_nr)->pageblock_flags;
141 page = virt_to_page(usemap);
142
143 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
144
145 for (i = 0; i < mapsize; i++, page++)
146 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
147
148}
149
150void register_page_bootmem_info_node(struct pglist_data *pgdat)
151{
152 unsigned long i, pfn, end_pfn, nr_pages;
153 int node = pgdat->node_id;
154 struct page *page;
155 struct zone *zone;
156
157 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
158 page = virt_to_page(pgdat);
159
160 for (i = 0; i < nr_pages; i++, page++)
161 get_page_bootmem(node, page, NODE_INFO);
162
163 zone = &pgdat->node_zones[0];
164 for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
165 if (zone->wait_table) {
166 nr_pages = zone->wait_table_hash_nr_entries
167 * sizeof(wait_queue_head_t);
168 nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
169 page = virt_to_page(zone->wait_table);
170
171 for (i = 0; i < nr_pages; i++, page++)
172 get_page_bootmem(node, page, NODE_INFO);
173 }
174 }
175
176 pfn = pgdat->node_start_pfn;
177 end_pfn = pfn + pgdat->node_spanned_pages;
178
179
180 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION)
181 register_page_bootmem_info_section(pfn);
182
183}
184#endif
185
186static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
187 unsigned long end_pfn)
188{
189 unsigned long old_zone_end_pfn;
190
191 zone_span_writelock(zone);
192
193 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
194 if (start_pfn < zone->zone_start_pfn)
195 zone->zone_start_pfn = start_pfn;
196
197 zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
198 zone->zone_start_pfn;
199
200 zone_span_writeunlock(zone);
201}
202
203static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
204 unsigned long end_pfn)
205{
206 unsigned long old_pgdat_end_pfn =
207 pgdat->node_start_pfn + pgdat->node_spanned_pages;
208
209 if (start_pfn < pgdat->node_start_pfn)
210 pgdat->node_start_pfn = start_pfn;
211
212 pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
213 pgdat->node_start_pfn;
214}
215
216static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
217{
218 struct pglist_data *pgdat = zone->zone_pgdat;
219 int nr_pages = PAGES_PER_SECTION;
220 int nid = pgdat->node_id;
221 int zone_type;
222 unsigned long flags;
223
224 zone_type = zone - pgdat->node_zones;
225 if (!zone->wait_table) {
226 int ret;
227
228 ret = init_currently_empty_zone(zone, phys_start_pfn,
229 nr_pages, MEMMAP_HOTPLUG);
230 if (ret)
231 return ret;
232 }
233 pgdat_resize_lock(zone->zone_pgdat, &flags);
234 grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
235 grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
236 phys_start_pfn + nr_pages);
237 pgdat_resize_unlock(zone->zone_pgdat, &flags);
238 memmap_init_zone(nr_pages, nid, zone_type,
239 phys_start_pfn, MEMMAP_HOTPLUG);
240 return 0;
241}
242
243static int __meminit __add_section(int nid, struct zone *zone,
244 unsigned long phys_start_pfn)
245{
246 int nr_pages = PAGES_PER_SECTION;
247 int ret;
248
249 if (pfn_valid(phys_start_pfn))
250 return -EEXIST;
251
252 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
253
254 if (ret < 0)
255 return ret;
256
257 ret = __add_zone(zone, phys_start_pfn);
258
259 if (ret < 0)
260 return ret;
261
262 return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
263}
264
265#ifdef CONFIG_SPARSEMEM_VMEMMAP
266static int __remove_section(struct zone *zone, struct mem_section *ms)
267{
268
269
270
271
272 return -EBUSY;
273}
274#else
275static int __remove_section(struct zone *zone, struct mem_section *ms)
276{
277 unsigned long flags;
278 struct pglist_data *pgdat = zone->zone_pgdat;
279 int ret = -EINVAL;
280
281 if (!valid_section(ms))
282 return ret;
283
284 ret = unregister_memory_section(ms);
285 if (ret)
286 return ret;
287
288 pgdat_resize_lock(pgdat, &flags);
289 sparse_remove_one_section(zone, ms);
290 pgdat_resize_unlock(pgdat, &flags);
291 return 0;
292}
293#endif
294
295
296
297
298
299
300
301int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
302 unsigned long nr_pages)
303{
304 unsigned long i;
305 int err = 0;
306 int start_sec, end_sec;
307
308 start_sec = pfn_to_section_nr(phys_start_pfn);
309 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
310
311 for (i = start_sec; i <= end_sec; i++) {
312 err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
313
314
315
316
317
318
319 if (err && (err != -EEXIST))
320 break;
321 err = 0;
322 }
323
324 return err;
325}
326EXPORT_SYMBOL_GPL(__add_pages);
327
328
329
330
331
332
333
334
335
336
337
338
339int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
340 unsigned long nr_pages)
341{
342 unsigned long i, ret = 0;
343 int sections_to_remove;
344
345
346
347
348 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
349 BUG_ON(nr_pages % PAGES_PER_SECTION);
350
351 sections_to_remove = nr_pages / PAGES_PER_SECTION;
352 for (i = 0; i < sections_to_remove; i++) {
353 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
354 release_mem_region(pfn << PAGE_SHIFT,
355 PAGES_PER_SECTION << PAGE_SHIFT);
356 ret = __remove_section(zone, __pfn_to_section(pfn));
357 if (ret)
358 break;
359 }
360 return ret;
361}
362EXPORT_SYMBOL_GPL(__remove_pages);
363
364void online_page(struct page *page)
365{
366 unsigned long pfn = page_to_pfn(page);
367
368 totalram_pages++;
369 if (pfn >= num_physpages)
370 num_physpages = pfn + 1;
371
372#ifdef CONFIG_HIGHMEM
373 if (PageHighMem(page))
374 totalhigh_pages++;
375#endif
376
377#ifdef CONFIG_FLATMEM
378 max_mapnr = max(pfn, max_mapnr);
379#endif
380
381 ClearPageReserved(page);
382 init_page_count(page);
383 __free_page(page);
384}
385
386static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
387 void *arg)
388{
389 unsigned long i;
390 unsigned long onlined_pages = *(unsigned long *)arg;
391 struct page *page;
392 if (PageReserved(pfn_to_page(start_pfn)))
393 for (i = 0; i < nr_pages; i++) {
394 page = pfn_to_page(start_pfn + i);
395 online_page(page);
396 onlined_pages++;
397 }
398 *(unsigned long *)arg = onlined_pages;
399 return 0;
400}
401
402
403int online_pages(unsigned long pfn, unsigned long nr_pages)
404{
405 unsigned long onlined_pages = 0;
406 struct zone *zone;
407 int need_zonelists_rebuild = 0;
408 int nid;
409 int ret;
410 struct memory_notify arg;
411
412 lock_memory_hotplug();
413 arg.start_pfn = pfn;
414 arg.nr_pages = nr_pages;
415 arg.status_change_nid = -1;
416
417 nid = page_to_nid(pfn_to_page(pfn));
418 if (node_present_pages(nid) == 0)
419 arg.status_change_nid = nid;
420
421 ret = memory_notify(MEM_GOING_ONLINE, &arg);
422 ret = notifier_to_errno(ret);
423 if (ret) {
424 memory_notify(MEM_CANCEL_ONLINE, &arg);
425 unlock_memory_hotplug();
426 return ret;
427 }
428
429
430
431
432
433 zone = page_zone(pfn_to_page(pfn));
434
435
436
437
438
439 mutex_lock(&zonelists_mutex);
440 if (!populated_zone(zone))
441 need_zonelists_rebuild = 1;
442
443 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
444 online_pages_range);
445 if (ret) {
446 mutex_unlock(&zonelists_mutex);
447 printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
448 nr_pages, pfn);
449 memory_notify(MEM_CANCEL_ONLINE, &arg);
450 unlock_memory_hotplug();
451 return ret;
452 }
453
454 zone->present_pages += onlined_pages;
455 zone->zone_pgdat->node_present_pages += onlined_pages;
456 if (need_zonelists_rebuild)
457 build_all_zonelists(zone);
458 else
459 zone_pcp_update(zone);
460
461 mutex_unlock(&zonelists_mutex);
462 setup_per_zone_wmarks();
463 calculate_zone_inactive_ratio(zone);
464 if (onlined_pages) {
465 kswapd_run(zone_to_nid(zone));
466 node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
467 }
468
469 vm_total_pages = nr_free_pagecache_pages();
470
471 writeback_set_ratelimit();
472
473 if (onlined_pages)
474 memory_notify(MEM_ONLINE, &arg);
475 unlock_memory_hotplug();
476
477 return 0;
478}
479#endif
480
481
482static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
483{
484 struct pglist_data *pgdat;
485 unsigned long zones_size[MAX_NR_ZONES] = {0};
486 unsigned long zholes_size[MAX_NR_ZONES] = {0};
487 unsigned long start_pfn = start >> PAGE_SHIFT;
488
489 pgdat = arch_alloc_nodedata(nid);
490 if (!pgdat)
491 return NULL;
492
493 arch_refresh_nodedata(nid, pgdat);
494
495
496
497
498 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
499
500 return pgdat;
501}
502
503static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
504{
505 arch_refresh_nodedata(nid, NULL);
506 arch_free_nodedata(pgdat);
507 return;
508}
509
510
511
512
513
514int mem_online_node(int nid)
515{
516 pg_data_t *pgdat;
517 int ret;
518
519 lock_memory_hotplug();
520 pgdat = hotadd_new_pgdat(nid, 0);
521 if (pgdat) {
522 ret = -ENOMEM;
523 goto out;
524 }
525 node_set_online(nid);
526 ret = register_one_node(nid);
527 BUG_ON(ret);
528
529out:
530 unlock_memory_hotplug();
531 return ret;
532}
533
534
535int __ref add_memory(int nid, u64 start, u64 size)
536{
537 pg_data_t *pgdat = NULL;
538 int new_pgdat = 0;
539 struct resource *res;
540 int ret;
541
542 lock_memory_hotplug();
543
544 res = register_memory_resource(start, size);
545 ret = -EEXIST;
546 if (!res)
547 goto out;
548
549 if (!node_online(nid)) {
550 pgdat = hotadd_new_pgdat(nid, start);
551 ret = -ENOMEM;
552 if (!pgdat)
553 goto out;
554 new_pgdat = 1;
555 }
556
557
558 ret = arch_add_memory(nid, start, size);
559
560 if (ret < 0)
561 goto error;
562
563
564 node_set_online(nid);
565
566 if (new_pgdat) {
567 ret = register_one_node(nid);
568
569
570
571
572
573 BUG_ON(ret);
574 }
575
576
577 firmware_map_add_hotplug(start, start + size, "System RAM");
578
579 goto out;
580
581error:
582
583 if (new_pgdat)
584 rollback_node_hotadd(nid, pgdat);
585 if (res)
586 release_memory_resource(res);
587
588out:
589 unlock_memory_hotplug();
590 return ret;
591}
592EXPORT_SYMBOL_GPL(add_memory);
593
594#ifdef CONFIG_MEMORY_HOTREMOVE
595
596
597
598
599
600
601
602static inline int pageblock_free(struct page *page)
603{
604 return PageBuddy(page) && page_order(page) >= pageblock_order;
605}
606
607
608static struct page *next_active_pageblock(struct page *page)
609{
610
611 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
612
613
614 if (pageblock_free(page)) {
615 int order;
616
617 order = page_order(page);
618 if ((order < MAX_ORDER) && (order >= pageblock_order))
619 return page + (1 << order);
620 }
621
622 return page + pageblock_nr_pages;
623}
624
625
626int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
627{
628 struct page *page = pfn_to_page(start_pfn);
629 struct page *end_page = page + nr_pages;
630
631
632 for (; page < end_page; page = next_active_pageblock(page)) {
633 if (!is_pageblock_removable_nolock(page))
634 return 0;
635 cond_resched();
636 }
637
638
639 return 1;
640}
641
642
643
644
645static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
646{
647 unsigned long pfn;
648 struct zone *zone = NULL;
649 struct page *page;
650 int i;
651 for (pfn = start_pfn;
652 pfn < end_pfn;
653 pfn += MAX_ORDER_NR_PAGES) {
654 i = 0;
655
656 while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i))
657 i++;
658 if (i == MAX_ORDER_NR_PAGES)
659 continue;
660 page = pfn_to_page(pfn + i);
661 if (zone && page_zone(page) != zone)
662 return 0;
663 zone = page_zone(page);
664 }
665 return 1;
666}
667
668
669
670
671
672static unsigned long scan_lru_pages(unsigned long start, unsigned long end)
673{
674 unsigned long pfn;
675 struct page *page;
676 for (pfn = start; pfn < end; pfn++) {
677 if (pfn_valid(pfn)) {
678 page = pfn_to_page(pfn);
679 if (PageLRU(page))
680 return pfn;
681 }
682 }
683 return 0;
684}
685
686static struct page *
687hotremove_migrate_alloc(struct page *page, unsigned long private, int **x)
688{
689
690 return alloc_page(GFP_HIGHUSER_MOVABLE);
691}
692
693#define NR_OFFLINE_AT_ONCE_PAGES (256)
694static int
695do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
696{
697 unsigned long pfn;
698 struct page *page;
699 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
700 int not_managed = 0;
701 int ret = 0;
702 LIST_HEAD(source);
703
704 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
705 if (!pfn_valid(pfn))
706 continue;
707 page = pfn_to_page(pfn);
708 if (!page_count(page))
709 continue;
710
711
712
713
714 ret = isolate_lru_page(page);
715 if (!ret) {
716 list_add_tail(&page->lru, &source);
717 move_pages--;
718 inc_zone_page_state(page, NR_ISOLATED_ANON +
719 page_is_file_cache(page));
720
721 } else {
722#ifdef CONFIG_DEBUG_VM
723 printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
724 pfn);
725 dump_page(page);
726#endif
727
728
729 if (page_count(page)) {
730 not_managed++;
731 ret = -EBUSY;
732 break;
733 }
734 }
735 }
736 if (!list_empty(&source)) {
737 if (not_managed) {
738 putback_lru_pages(&source);
739 goto out;
740 }
741
742 ret = migrate_pages(&source, hotremove_migrate_alloc, 0,
743 true, true);
744 if (ret)
745 putback_lru_pages(&source);
746 }
747out:
748 return ret;
749}
750
751
752
753
754static int
755offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
756 void *data)
757{
758 __offline_isolated_pages(start, start + nr_pages);
759 return 0;
760}
761
762static void
763offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
764{
765 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
766 offline_isolated_pages_cb);
767}
768
769
770
771
772static int
773check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
774 void *data)
775{
776 int ret;
777 long offlined = *(long *)data;
778 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages);
779 offlined = nr_pages;
780 if (!ret)
781 *(long *)data += offlined;
782 return ret;
783}
784
785static long
786check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
787{
788 long offlined = 0;
789 int ret;
790
791 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
792 check_pages_isolated_cb);
793 if (ret < 0)
794 offlined = (long)ret;
795 return offlined;
796}
797
798static int offline_pages(unsigned long start_pfn,
799 unsigned long end_pfn, unsigned long timeout)
800{
801 unsigned long pfn, nr_pages, expire;
802 long offlined_pages;
803 int ret, drain, retry_max, node;
804 struct zone *zone;
805 struct memory_notify arg;
806
807 BUG_ON(start_pfn >= end_pfn);
808
809 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
810 return -EINVAL;
811 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
812 return -EINVAL;
813
814
815 if (!test_pages_in_a_zone(start_pfn, end_pfn))
816 return -EINVAL;
817
818 lock_memory_hotplug();
819
820 zone = page_zone(pfn_to_page(start_pfn));
821 node = zone_to_nid(zone);
822 nr_pages = end_pfn - start_pfn;
823
824
825 ret = start_isolate_page_range(start_pfn, end_pfn);
826 if (ret)
827 goto out;
828
829 arg.start_pfn = start_pfn;
830 arg.nr_pages = nr_pages;
831 arg.status_change_nid = -1;
832 if (nr_pages >= node_present_pages(node))
833 arg.status_change_nid = node;
834
835 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
836 ret = notifier_to_errno(ret);
837 if (ret)
838 goto failed_removal;
839
840 pfn = start_pfn;
841 expire = jiffies + timeout;
842 drain = 0;
843 retry_max = 5;
844repeat:
845
846 ret = -EAGAIN;
847 if (time_after(jiffies, expire))
848 goto failed_removal;
849 ret = -EINTR;
850 if (signal_pending(current))
851 goto failed_removal;
852 ret = 0;
853 if (drain) {
854 lru_add_drain_all();
855 cond_resched();
856 drain_all_pages();
857 }
858
859 pfn = scan_lru_pages(start_pfn, end_pfn);
860 if (pfn) {
861 ret = do_migrate_range(pfn, end_pfn);
862 if (!ret) {
863 drain = 1;
864 goto repeat;
865 } else {
866 if (ret < 0)
867 if (--retry_max == 0)
868 goto failed_removal;
869 yield();
870 drain = 1;
871 goto repeat;
872 }
873 }
874
875 lru_add_drain_all();
876 yield();
877
878 drain_all_pages();
879
880 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
881 if (offlined_pages < 0) {
882 ret = -EBUSY;
883 goto failed_removal;
884 }
885 printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
886
887
888 offline_isolated_pages(start_pfn, end_pfn);
889
890 undo_isolate_page_range(start_pfn, end_pfn);
891
892 zone->present_pages -= offlined_pages;
893 zone->zone_pgdat->node_present_pages -= offlined_pages;
894 totalram_pages -= offlined_pages;
895
896 setup_per_zone_wmarks();
897 calculate_zone_inactive_ratio(zone);
898 if (!node_present_pages(node)) {
899 node_clear_state(node, N_HIGH_MEMORY);
900 kswapd_stop(node);
901 }
902
903 vm_total_pages = nr_free_pagecache_pages();
904 writeback_set_ratelimit();
905
906 memory_notify(MEM_OFFLINE, &arg);
907 unlock_memory_hotplug();
908 return 0;
909
910failed_removal:
911 printk(KERN_INFO "memory offlining %lx to %lx failed\n",
912 start_pfn, end_pfn);
913 memory_notify(MEM_CANCEL_OFFLINE, &arg);
914
915 undo_isolate_page_range(start_pfn, end_pfn);
916
917out:
918 unlock_memory_hotplug();
919 return ret;
920}
921
922int remove_memory(u64 start, u64 size)
923{
924 unsigned long start_pfn, end_pfn;
925
926 start_pfn = PFN_DOWN(start);
927 end_pfn = start_pfn + PFN_DOWN(size);
928 return offline_pages(start_pfn, end_pfn, 120 * HZ);
929}
930#else
931int remove_memory(u64 start, u64 size)
932{
933 return -EINVAL;
934}
935#endif
936EXPORT_SYMBOL_GPL(remove_memory);
937