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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/compiler.h>
13#include <linux/export.h>
14#include <linux/pagevec.h>
15#include <linux/writeback.h>
16#include <linux/slab.h>
17#include <linux/sysctl.h>
18#include <linux/cpu.h>
19#include <linux/memory.h>
20#include <linux/memory_hotplug.h>
21#include <linux/highmem.h>
22#include <linux/vmalloc.h>
23#include <linux/ioport.h>
24#include <linux/delay.h>
25#include <linux/migrate.h>
26#include <linux/page-isolation.h>
27#include <linux/pfn.h>
28#include <linux/suspend.h>
29#include <linux/mm_inline.h>
30#include <linux/firmware-map.h>
31#include <linux/stop_machine.h>
32#include <linux/hugetlb.h>
33#include <linux/memblock.h>
34
35#include <asm/tlbflush.h>
36
37#include "internal.h"
38
39
40
41
42
43
44
45
46static void generic_online_page(struct page *page);
47
48static online_page_callback_t online_page_callback = generic_online_page;
49static DEFINE_MUTEX(online_page_callback_lock);
50
51
52static struct {
53 struct task_struct *active_writer;
54 struct mutex lock;
55
56
57
58
59 int refcount;
60
61#ifdef CONFIG_DEBUG_LOCK_ALLOC
62 struct lockdep_map dep_map;
63#endif
64} mem_hotplug = {
65 .active_writer = NULL,
66 .lock = __MUTEX_INITIALIZER(mem_hotplug.lock),
67 .refcount = 0,
68#ifdef CONFIG_DEBUG_LOCK_ALLOC
69 .dep_map = {.name = "mem_hotplug.lock" },
70#endif
71};
72
73
74#define memhp_lock_acquire_read() lock_map_acquire_read(&mem_hotplug.dep_map)
75#define memhp_lock_acquire() lock_map_acquire(&mem_hotplug.dep_map)
76#define memhp_lock_release() lock_map_release(&mem_hotplug.dep_map)
77
78void get_online_mems(void)
79{
80 might_sleep();
81 if (mem_hotplug.active_writer == current)
82 return;
83 memhp_lock_acquire_read();
84 mutex_lock(&mem_hotplug.lock);
85 mem_hotplug.refcount++;
86 mutex_unlock(&mem_hotplug.lock);
87
88}
89
90void put_online_mems(void)
91{
92 if (mem_hotplug.active_writer == current)
93 return;
94 mutex_lock(&mem_hotplug.lock);
95
96 if (WARN_ON(!mem_hotplug.refcount))
97 mem_hotplug.refcount++;
98
99 if (!--mem_hotplug.refcount && unlikely(mem_hotplug.active_writer))
100 wake_up_process(mem_hotplug.active_writer);
101 mutex_unlock(&mem_hotplug.lock);
102 memhp_lock_release();
103
104}
105
106static void mem_hotplug_begin(void)
107{
108 mem_hotplug.active_writer = current;
109
110 memhp_lock_acquire();
111 for (;;) {
112 mutex_lock(&mem_hotplug.lock);
113 if (likely(!mem_hotplug.refcount))
114 break;
115 __set_current_state(TASK_UNINTERRUPTIBLE);
116 mutex_unlock(&mem_hotplug.lock);
117 schedule();
118 }
119}
120
121static void mem_hotplug_done(void)
122{
123 mem_hotplug.active_writer = NULL;
124 mutex_unlock(&mem_hotplug.lock);
125 memhp_lock_release();
126}
127
128
129static struct resource *register_memory_resource(u64 start, u64 size)
130{
131 struct resource *res;
132 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
133 BUG_ON(!res);
134
135 res->name = "System RAM";
136 res->start = start;
137 res->end = start + size - 1;
138 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
139 if (request_resource(&iomem_resource, res) < 0) {
140 pr_debug("System RAM resource %pR cannot be added\n", res);
141 kfree(res);
142 res = NULL;
143 }
144 return res;
145}
146
147static void release_memory_resource(struct resource *res)
148{
149 if (!res)
150 return;
151 release_resource(res);
152 kfree(res);
153 return;
154}
155
156#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
157void get_page_bootmem(unsigned long info, struct page *page,
158 unsigned long type)
159{
160 page->lru.next = (struct list_head *) type;
161 SetPagePrivate(page);
162 set_page_private(page, info);
163 atomic_inc(&page->_count);
164}
165
166void put_page_bootmem(struct page *page)
167{
168 unsigned long type;
169
170 type = (unsigned long) page->lru.next;
171 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
172 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
173
174 if (atomic_dec_return(&page->_count) == 1) {
175 ClearPagePrivate(page);
176 set_page_private(page, 0);
177 INIT_LIST_HEAD(&page->lru);
178 free_reserved_page(page);
179 }
180}
181
182#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
183#ifndef CONFIG_SPARSEMEM_VMEMMAP
184static void register_page_bootmem_info_section(unsigned long start_pfn)
185{
186 unsigned long *usemap, mapsize, section_nr, i;
187 struct mem_section *ms;
188 struct page *page, *memmap;
189
190 section_nr = pfn_to_section_nr(start_pfn);
191 ms = __nr_to_section(section_nr);
192
193
194 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
195
196
197
198
199
200 page = virt_to_page(memmap);
201 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
202 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
203
204
205 for (i = 0; i < mapsize; i++, page++)
206 get_page_bootmem(section_nr, page, SECTION_INFO);
207
208 usemap = __nr_to_section(section_nr)->pageblock_flags;
209 page = virt_to_page(usemap);
210
211 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
212
213 for (i = 0; i < mapsize; i++, page++)
214 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
215
216}
217#else
218static void register_page_bootmem_info_section(unsigned long start_pfn)
219{
220 unsigned long *usemap, mapsize, section_nr, i;
221 struct mem_section *ms;
222 struct page *page, *memmap;
223
224 if (!pfn_valid(start_pfn))
225 return;
226
227 section_nr = pfn_to_section_nr(start_pfn);
228 ms = __nr_to_section(section_nr);
229
230 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
231
232 register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
233
234 usemap = __nr_to_section(section_nr)->pageblock_flags;
235 page = virt_to_page(usemap);
236
237 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
238
239 for (i = 0; i < mapsize; i++, page++)
240 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
241}
242#endif
243
244void register_page_bootmem_info_node(struct pglist_data *pgdat)
245{
246 unsigned long i, pfn, end_pfn, nr_pages;
247 int node = pgdat->node_id;
248 struct page *page;
249 struct zone *zone;
250
251 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
252 page = virt_to_page(pgdat);
253
254 for (i = 0; i < nr_pages; i++, page++)
255 get_page_bootmem(node, page, NODE_INFO);
256
257 zone = &pgdat->node_zones[0];
258 for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
259 if (zone_is_initialized(zone)) {
260 nr_pages = zone->wait_table_hash_nr_entries
261 * sizeof(wait_queue_head_t);
262 nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
263 page = virt_to_page(zone->wait_table);
264
265 for (i = 0; i < nr_pages; i++, page++)
266 get_page_bootmem(node, page, NODE_INFO);
267 }
268 }
269
270 pfn = pgdat->node_start_pfn;
271 end_pfn = pgdat_end_pfn(pgdat);
272
273
274 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
275
276
277
278
279
280
281 if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node))
282 register_page_bootmem_info_section(pfn);
283 }
284}
285#endif
286
287static void __meminit grow_zone_span(struct zone *zone, unsigned long start_pfn,
288 unsigned long end_pfn)
289{
290 unsigned long old_zone_end_pfn;
291
292 zone_span_writelock(zone);
293
294 old_zone_end_pfn = zone_end_pfn(zone);
295 if (zone_is_empty(zone) || start_pfn < zone->zone_start_pfn)
296 zone->zone_start_pfn = start_pfn;
297
298 zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
299 zone->zone_start_pfn;
300
301 zone_span_writeunlock(zone);
302}
303
304static void resize_zone(struct zone *zone, unsigned long start_pfn,
305 unsigned long end_pfn)
306{
307 zone_span_writelock(zone);
308
309 if (end_pfn - start_pfn) {
310 zone->zone_start_pfn = start_pfn;
311 zone->spanned_pages = end_pfn - start_pfn;
312 } else {
313
314
315
316
317 zone->zone_start_pfn = 0;
318 zone->spanned_pages = 0;
319 }
320
321 zone_span_writeunlock(zone);
322}
323
324static void fix_zone_id(struct zone *zone, unsigned long start_pfn,
325 unsigned long end_pfn)
326{
327 enum zone_type zid = zone_idx(zone);
328 int nid = zone->zone_pgdat->node_id;
329 unsigned long pfn;
330
331 for (pfn = start_pfn; pfn < end_pfn; pfn++)
332 set_page_links(pfn_to_page(pfn), zid, nid, pfn);
333}
334
335
336
337static int __ref ensure_zone_is_initialized(struct zone *zone,
338 unsigned long start_pfn, unsigned long num_pages)
339{
340 if (!zone_is_initialized(zone))
341 return init_currently_empty_zone(zone, start_pfn, num_pages,
342 MEMMAP_HOTPLUG);
343 return 0;
344}
345
346static int __meminit move_pfn_range_left(struct zone *z1, struct zone *z2,
347 unsigned long start_pfn, unsigned long end_pfn)
348{
349 int ret;
350 unsigned long flags;
351 unsigned long z1_start_pfn;
352
353 ret = ensure_zone_is_initialized(z1, start_pfn, end_pfn - start_pfn);
354 if (ret)
355 return ret;
356
357 pgdat_resize_lock(z1->zone_pgdat, &flags);
358
359
360 if (end_pfn > zone_end_pfn(z2))
361 goto out_fail;
362
363 if (start_pfn > z2->zone_start_pfn)
364 goto out_fail;
365
366 if (end_pfn <= z2->zone_start_pfn)
367 goto out_fail;
368
369
370 if (!zone_is_empty(z1))
371 z1_start_pfn = z1->zone_start_pfn;
372 else
373 z1_start_pfn = start_pfn;
374
375 resize_zone(z1, z1_start_pfn, end_pfn);
376 resize_zone(z2, end_pfn, zone_end_pfn(z2));
377
378 pgdat_resize_unlock(z1->zone_pgdat, &flags);
379
380 fix_zone_id(z1, start_pfn, end_pfn);
381
382 return 0;
383out_fail:
384 pgdat_resize_unlock(z1->zone_pgdat, &flags);
385 return -1;
386}
387
388static int __meminit move_pfn_range_right(struct zone *z1, struct zone *z2,
389 unsigned long start_pfn, unsigned long end_pfn)
390{
391 int ret;
392 unsigned long flags;
393 unsigned long z2_end_pfn;
394
395 ret = ensure_zone_is_initialized(z2, start_pfn, end_pfn - start_pfn);
396 if (ret)
397 return ret;
398
399 pgdat_resize_lock(z1->zone_pgdat, &flags);
400
401
402 if (z1->zone_start_pfn > start_pfn)
403 goto out_fail;
404
405 if (zone_end_pfn(z1) > end_pfn)
406 goto out_fail;
407
408 if (start_pfn >= zone_end_pfn(z1))
409 goto out_fail;
410
411
412 if (!zone_is_empty(z2))
413 z2_end_pfn = zone_end_pfn(z2);
414 else
415 z2_end_pfn = end_pfn;
416
417 resize_zone(z1, z1->zone_start_pfn, start_pfn);
418 resize_zone(z2, start_pfn, z2_end_pfn);
419
420 pgdat_resize_unlock(z1->zone_pgdat, &flags);
421
422 fix_zone_id(z2, start_pfn, end_pfn);
423
424 return 0;
425out_fail:
426 pgdat_resize_unlock(z1->zone_pgdat, &flags);
427 return -1;
428}
429
430static void __meminit grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
431 unsigned long end_pfn)
432{
433 unsigned long old_pgdat_end_pfn = pgdat_end_pfn(pgdat);
434
435 if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
436 pgdat->node_start_pfn = start_pfn;
437
438 pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
439 pgdat->node_start_pfn;
440}
441
442static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
443{
444 struct pglist_data *pgdat = zone->zone_pgdat;
445 int nr_pages = PAGES_PER_SECTION;
446 int nid = pgdat->node_id;
447 int zone_type;
448 unsigned long flags;
449 int ret;
450
451 zone_type = zone - pgdat->node_zones;
452 ret = ensure_zone_is_initialized(zone, phys_start_pfn, nr_pages);
453 if (ret)
454 return ret;
455
456 pgdat_resize_lock(zone->zone_pgdat, &flags);
457 grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
458 grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
459 phys_start_pfn + nr_pages);
460 pgdat_resize_unlock(zone->zone_pgdat, &flags);
461 memmap_init_zone(nr_pages, nid, zone_type,
462 phys_start_pfn, MEMMAP_HOTPLUG);
463 return 0;
464}
465
466static int __meminit __add_section(int nid, struct zone *zone,
467 unsigned long phys_start_pfn)
468{
469 int ret;
470
471 if (pfn_valid(phys_start_pfn))
472 return -EEXIST;
473
474 ret = sparse_add_one_section(zone, phys_start_pfn);
475
476 if (ret < 0)
477 return ret;
478
479 ret = __add_zone(zone, phys_start_pfn);
480
481 if (ret < 0)
482 return ret;
483
484 return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
485}
486
487
488
489
490
491
492
493int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
494 unsigned long nr_pages)
495{
496 unsigned long i;
497 int err = 0;
498 int start_sec, end_sec;
499
500 start_sec = pfn_to_section_nr(phys_start_pfn);
501 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
502
503 for (i = start_sec; i <= end_sec; i++) {
504 err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
505
506
507
508
509
510
511 if (err && (err != -EEXIST))
512 break;
513 err = 0;
514 }
515
516 return err;
517}
518EXPORT_SYMBOL_GPL(__add_pages);
519
520#ifdef CONFIG_MEMORY_HOTREMOVE
521
522static int find_smallest_section_pfn(int nid, struct zone *zone,
523 unsigned long start_pfn,
524 unsigned long end_pfn)
525{
526 struct mem_section *ms;
527
528 for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
529 ms = __pfn_to_section(start_pfn);
530
531 if (unlikely(!valid_section(ms)))
532 continue;
533
534 if (unlikely(pfn_to_nid(start_pfn) != nid))
535 continue;
536
537 if (zone && zone != page_zone(pfn_to_page(start_pfn)))
538 continue;
539
540 return start_pfn;
541 }
542
543 return 0;
544}
545
546
547static int find_biggest_section_pfn(int nid, struct zone *zone,
548 unsigned long start_pfn,
549 unsigned long end_pfn)
550{
551 struct mem_section *ms;
552 unsigned long pfn;
553
554
555 pfn = end_pfn - 1;
556 for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
557 ms = __pfn_to_section(pfn);
558
559 if (unlikely(!valid_section(ms)))
560 continue;
561
562 if (unlikely(pfn_to_nid(pfn) != nid))
563 continue;
564
565 if (zone && zone != page_zone(pfn_to_page(pfn)))
566 continue;
567
568 return pfn;
569 }
570
571 return 0;
572}
573
574static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
575 unsigned long end_pfn)
576{
577 unsigned long zone_start_pfn = zone->zone_start_pfn;
578 unsigned long z = zone_end_pfn(zone);
579 unsigned long zone_end_pfn = z;
580 unsigned long pfn;
581 struct mem_section *ms;
582 int nid = zone_to_nid(zone);
583
584 zone_span_writelock(zone);
585 if (zone_start_pfn == start_pfn) {
586
587
588
589
590
591
592 pfn = find_smallest_section_pfn(nid, zone, end_pfn,
593 zone_end_pfn);
594 if (pfn) {
595 zone->zone_start_pfn = pfn;
596 zone->spanned_pages = zone_end_pfn - pfn;
597 }
598 } else if (zone_end_pfn == end_pfn) {
599
600
601
602
603
604
605 pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
606 start_pfn);
607 if (pfn)
608 zone->spanned_pages = pfn - zone_start_pfn + 1;
609 }
610
611
612
613
614
615
616
617 pfn = zone_start_pfn;
618 for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
619 ms = __pfn_to_section(pfn);
620
621 if (unlikely(!valid_section(ms)))
622 continue;
623
624 if (page_zone(pfn_to_page(pfn)) != zone)
625 continue;
626
627
628 if (start_pfn == pfn)
629 continue;
630
631
632 zone_span_writeunlock(zone);
633 return;
634 }
635
636
637 zone->zone_start_pfn = 0;
638 zone->spanned_pages = 0;
639 zone_span_writeunlock(zone);
640}
641
642static void shrink_pgdat_span(struct pglist_data *pgdat,
643 unsigned long start_pfn, unsigned long end_pfn)
644{
645 unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
646 unsigned long p = pgdat_end_pfn(pgdat);
647 unsigned long pgdat_end_pfn = p;
648 unsigned long pfn;
649 struct mem_section *ms;
650 int nid = pgdat->node_id;
651
652 if (pgdat_start_pfn == start_pfn) {
653
654
655
656
657
658
659 pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
660 pgdat_end_pfn);
661 if (pfn) {
662 pgdat->node_start_pfn = pfn;
663 pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
664 }
665 } else if (pgdat_end_pfn == end_pfn) {
666
667
668
669
670
671
672 pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
673 start_pfn);
674 if (pfn)
675 pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
676 }
677
678
679
680
681
682
683
684
685 pfn = pgdat_start_pfn;
686 for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
687 ms = __pfn_to_section(pfn);
688
689 if (unlikely(!valid_section(ms)))
690 continue;
691
692 if (pfn_to_nid(pfn) != nid)
693 continue;
694
695
696 if (start_pfn == pfn)
697 continue;
698
699
700 return;
701 }
702
703
704 pgdat->node_start_pfn = 0;
705 pgdat->node_spanned_pages = 0;
706}
707
708static void __remove_zone(struct zone *zone, unsigned long start_pfn)
709{
710 struct pglist_data *pgdat = zone->zone_pgdat;
711 int nr_pages = PAGES_PER_SECTION;
712 int zone_type;
713 unsigned long flags;
714
715 zone_type = zone - pgdat->node_zones;
716
717 pgdat_resize_lock(zone->zone_pgdat, &flags);
718 shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
719 shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
720 pgdat_resize_unlock(zone->zone_pgdat, &flags);
721}
722
723static int __remove_section(struct zone *zone, struct mem_section *ms)
724{
725 unsigned long start_pfn;
726 int scn_nr;
727 int ret = -EINVAL;
728
729 if (!valid_section(ms))
730 return ret;
731
732 ret = unregister_memory_section(ms);
733 if (ret)
734 return ret;
735
736 scn_nr = __section_nr(ms);
737 start_pfn = section_nr_to_pfn(scn_nr);
738 __remove_zone(zone, start_pfn);
739
740 sparse_remove_one_section(zone, ms);
741 return 0;
742}
743
744
745
746
747
748
749
750
751
752
753
754
755int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
756 unsigned long nr_pages)
757{
758 unsigned long i;
759 int sections_to_remove;
760 resource_size_t start, size;
761 int ret = 0;
762
763
764
765
766 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
767 BUG_ON(nr_pages % PAGES_PER_SECTION);
768
769 start = phys_start_pfn << PAGE_SHIFT;
770 size = nr_pages * PAGE_SIZE;
771 ret = release_mem_region_adjustable(&iomem_resource, start, size);
772 if (ret) {
773 resource_size_t endres = start + size - 1;
774
775 pr_warn("Unable to release resource <%pa-%pa> (%d)\n",
776 &start, &endres, ret);
777 }
778
779 sections_to_remove = nr_pages / PAGES_PER_SECTION;
780 for (i = 0; i < sections_to_remove; i++) {
781 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
782 ret = __remove_section(zone, __pfn_to_section(pfn));
783 if (ret)
784 break;
785 }
786 return ret;
787}
788EXPORT_SYMBOL_GPL(__remove_pages);
789#endif
790
791int set_online_page_callback(online_page_callback_t callback)
792{
793 int rc = -EINVAL;
794
795 get_online_mems();
796 mutex_lock(&online_page_callback_lock);
797
798 if (online_page_callback == generic_online_page) {
799 online_page_callback = callback;
800 rc = 0;
801 }
802
803 mutex_unlock(&online_page_callback_lock);
804 put_online_mems();
805
806 return rc;
807}
808EXPORT_SYMBOL_GPL(set_online_page_callback);
809
810int restore_online_page_callback(online_page_callback_t callback)
811{
812 int rc = -EINVAL;
813
814 get_online_mems();
815 mutex_lock(&online_page_callback_lock);
816
817 if (online_page_callback == callback) {
818 online_page_callback = generic_online_page;
819 rc = 0;
820 }
821
822 mutex_unlock(&online_page_callback_lock);
823 put_online_mems();
824
825 return rc;
826}
827EXPORT_SYMBOL_GPL(restore_online_page_callback);
828
829void __online_page_set_limits(struct page *page)
830{
831}
832EXPORT_SYMBOL_GPL(__online_page_set_limits);
833
834void __online_page_increment_counters(struct page *page)
835{
836 adjust_managed_page_count(page, 1);
837}
838EXPORT_SYMBOL_GPL(__online_page_increment_counters);
839
840void __online_page_free(struct page *page)
841{
842 __free_reserved_page(page);
843}
844EXPORT_SYMBOL_GPL(__online_page_free);
845
846static void generic_online_page(struct page *page)
847{
848 __online_page_set_limits(page);
849 __online_page_increment_counters(page);
850 __online_page_free(page);
851}
852
853static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
854 void *arg)
855{
856 unsigned long i;
857 unsigned long onlined_pages = *(unsigned long *)arg;
858 struct page *page;
859 if (PageReserved(pfn_to_page(start_pfn)))
860 for (i = 0; i < nr_pages; i++) {
861 page = pfn_to_page(start_pfn + i);
862 (*online_page_callback)(page);
863 onlined_pages++;
864 }
865 *(unsigned long *)arg = onlined_pages;
866 return 0;
867}
868
869#ifdef CONFIG_MOVABLE_NODE
870
871
872
873
874static bool can_online_high_movable(struct zone *zone)
875{
876 return true;
877}
878#else
879
880static bool can_online_high_movable(struct zone *zone)
881{
882 return node_state(zone_to_nid(zone), N_NORMAL_MEMORY);
883}
884#endif
885
886
887static void node_states_check_changes_online(unsigned long nr_pages,
888 struct zone *zone, struct memory_notify *arg)
889{
890 int nid = zone_to_nid(zone);
891 enum zone_type zone_last = ZONE_NORMAL;
892
893
894
895
896
897
898
899
900
901
902 if (N_MEMORY == N_NORMAL_MEMORY)
903 zone_last = ZONE_MOVABLE;
904
905
906
907
908
909
910
911 if (zone_idx(zone) <= zone_last && !node_state(nid, N_NORMAL_MEMORY))
912 arg->status_change_nid_normal = nid;
913 else
914 arg->status_change_nid_normal = -1;
915
916#ifdef CONFIG_HIGHMEM
917
918
919
920
921
922
923
924
925
926 zone_last = ZONE_HIGHMEM;
927 if (N_MEMORY == N_HIGH_MEMORY)
928 zone_last = ZONE_MOVABLE;
929
930 if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
931 arg->status_change_nid_high = nid;
932 else
933 arg->status_change_nid_high = -1;
934#else
935 arg->status_change_nid_high = arg->status_change_nid_normal;
936#endif
937
938
939
940
941
942
943 if (!node_state(nid, N_MEMORY))
944 arg->status_change_nid = nid;
945 else
946 arg->status_change_nid = -1;
947}
948
949static void node_states_set_node(int node, struct memory_notify *arg)
950{
951 if (arg->status_change_nid_normal >= 0)
952 node_set_state(node, N_NORMAL_MEMORY);
953
954 if (arg->status_change_nid_high >= 0)
955 node_set_state(node, N_HIGH_MEMORY);
956
957 node_set_state(node, N_MEMORY);
958}
959
960
961int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
962{
963 unsigned long flags;
964 unsigned long onlined_pages = 0;
965 struct zone *zone;
966 int need_zonelists_rebuild = 0;
967 int nid;
968 int ret;
969 struct memory_notify arg;
970
971 mem_hotplug_begin();
972
973
974
975
976
977 zone = page_zone(pfn_to_page(pfn));
978
979 ret = -EINVAL;
980 if ((zone_idx(zone) > ZONE_NORMAL ||
981 online_type == MMOP_ONLINE_MOVABLE) &&
982 !can_online_high_movable(zone))
983 goto out;
984
985 if (online_type == MMOP_ONLINE_KERNEL &&
986 zone_idx(zone) == ZONE_MOVABLE) {
987 if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages))
988 goto out;
989 }
990 if (online_type == MMOP_ONLINE_MOVABLE &&
991 zone_idx(zone) == ZONE_MOVABLE - 1) {
992 if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages))
993 goto out;
994 }
995
996
997 zone = page_zone(pfn_to_page(pfn));
998
999 arg.start_pfn = pfn;
1000 arg.nr_pages = nr_pages;
1001 node_states_check_changes_online(nr_pages, zone, &arg);
1002
1003 nid = pfn_to_nid(pfn);
1004
1005 ret = memory_notify(MEM_GOING_ONLINE, &arg);
1006 ret = notifier_to_errno(ret);
1007 if (ret) {
1008 memory_notify(MEM_CANCEL_ONLINE, &arg);
1009 goto out;
1010 }
1011
1012
1013
1014
1015
1016 mutex_lock(&zonelists_mutex);
1017 if (!populated_zone(zone)) {
1018 need_zonelists_rebuild = 1;
1019 build_all_zonelists(NULL, zone);
1020 }
1021
1022 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
1023 online_pages_range);
1024 if (ret) {
1025 if (need_zonelists_rebuild)
1026 zone_pcp_reset(zone);
1027 mutex_unlock(&zonelists_mutex);
1028 printk(KERN_DEBUG "online_pages [mem %#010llx-%#010llx] failed\n",
1029 (unsigned long long) pfn << PAGE_SHIFT,
1030 (((unsigned long long) pfn + nr_pages)
1031 << PAGE_SHIFT) - 1);
1032 memory_notify(MEM_CANCEL_ONLINE, &arg);
1033 goto out;
1034 }
1035
1036 zone->present_pages += onlined_pages;
1037
1038 pgdat_resize_lock(zone->zone_pgdat, &flags);
1039 zone->zone_pgdat->node_present_pages += onlined_pages;
1040 pgdat_resize_unlock(zone->zone_pgdat, &flags);
1041
1042 if (onlined_pages) {
1043 node_states_set_node(zone_to_nid(zone), &arg);
1044 if (need_zonelists_rebuild)
1045 build_all_zonelists(NULL, NULL);
1046 else
1047 zone_pcp_update(zone);
1048 }
1049
1050 mutex_unlock(&zonelists_mutex);
1051
1052 init_per_zone_wmark_min();
1053
1054 if (onlined_pages)
1055 kswapd_run(zone_to_nid(zone));
1056
1057 vm_total_pages = nr_free_pagecache_pages();
1058
1059 writeback_set_ratelimit();
1060
1061 if (onlined_pages)
1062 memory_notify(MEM_ONLINE, &arg);
1063out:
1064 mem_hotplug_done();
1065 return ret;
1066}
1067#endif
1068
1069
1070static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
1071{
1072 struct pglist_data *pgdat;
1073 unsigned long zones_size[MAX_NR_ZONES] = {0};
1074 unsigned long zholes_size[MAX_NR_ZONES] = {0};
1075 unsigned long start_pfn = PFN_DOWN(start);
1076
1077 pgdat = NODE_DATA(nid);
1078 if (!pgdat) {
1079 pgdat = arch_alloc_nodedata(nid);
1080 if (!pgdat)
1081 return NULL;
1082
1083 arch_refresh_nodedata(nid, pgdat);
1084 }
1085
1086
1087
1088
1089 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
1090
1091
1092
1093
1094
1095 mutex_lock(&zonelists_mutex);
1096 build_all_zonelists(pgdat, NULL);
1097 mutex_unlock(&zonelists_mutex);
1098
1099 return pgdat;
1100}
1101
1102static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
1103{
1104 arch_refresh_nodedata(nid, NULL);
1105 arch_free_nodedata(pgdat);
1106 return;
1107}
1108
1109
1110
1111
1112
1113
1114
1115int try_online_node(int nid)
1116{
1117 pg_data_t *pgdat;
1118 int ret;
1119
1120 if (node_online(nid))
1121 return 0;
1122
1123 mem_hotplug_begin();
1124 pgdat = hotadd_new_pgdat(nid, 0);
1125 if (!pgdat) {
1126 pr_err("Cannot online node %d due to NULL pgdat\n", nid);
1127 ret = -ENOMEM;
1128 goto out;
1129 }
1130 node_set_online(nid);
1131 ret = register_one_node(nid);
1132 BUG_ON(ret);
1133
1134 if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
1135 mutex_lock(&zonelists_mutex);
1136 build_all_zonelists(NULL, NULL);
1137 mutex_unlock(&zonelists_mutex);
1138 }
1139
1140out:
1141 mem_hotplug_done();
1142 return ret;
1143}
1144
1145static int check_hotplug_memory_range(u64 start, u64 size)
1146{
1147 u64 start_pfn = PFN_DOWN(start);
1148 u64 nr_pages = size >> PAGE_SHIFT;
1149
1150
1151 if ((start_pfn & ~PAGE_SECTION_MASK) ||
1152 (nr_pages % PAGES_PER_SECTION) || (!nr_pages)) {
1153 pr_err("Section-unaligned hotplug range: start 0x%llx, size 0x%llx\n",
1154 (unsigned long long)start,
1155 (unsigned long long)size);
1156 return -EINVAL;
1157 }
1158
1159 return 0;
1160}
1161
1162
1163
1164
1165
1166
1167static int should_add_memory_movable(int nid, u64 start, u64 size)
1168{
1169 unsigned long start_pfn = start >> PAGE_SHIFT;
1170 pg_data_t *pgdat = NODE_DATA(nid);
1171 struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE;
1172
1173 if (zone_is_empty(movable_zone))
1174 return 0;
1175
1176 if (movable_zone->zone_start_pfn <= start_pfn)
1177 return 1;
1178
1179 return 0;
1180}
1181
1182int zone_for_memory(int nid, u64 start, u64 size, int zone_default)
1183{
1184 if (should_add_memory_movable(nid, start, size))
1185 return ZONE_MOVABLE;
1186
1187 return zone_default;
1188}
1189
1190
1191int __ref add_memory(int nid, u64 start, u64 size)
1192{
1193 pg_data_t *pgdat = NULL;
1194 bool new_pgdat;
1195 bool new_node;
1196 struct resource *res;
1197 int ret;
1198
1199 ret = check_hotplug_memory_range(start, size);
1200 if (ret)
1201 return ret;
1202
1203 res = register_memory_resource(start, size);
1204 ret = -EEXIST;
1205 if (!res)
1206 return ret;
1207
1208 {
1209 void *p = NODE_DATA(nid);
1210 new_pgdat = !p;
1211 }
1212
1213 mem_hotplug_begin();
1214
1215 new_node = !node_online(nid);
1216 if (new_node) {
1217 pgdat = hotadd_new_pgdat(nid, start);
1218 ret = -ENOMEM;
1219 if (!pgdat)
1220 goto error;
1221 }
1222
1223
1224 ret = arch_add_memory(nid, start, size);
1225
1226 if (ret < 0)
1227 goto error;
1228
1229
1230 node_set_online(nid);
1231
1232 if (new_node) {
1233 ret = register_one_node(nid);
1234
1235
1236
1237
1238
1239 BUG_ON(ret);
1240 }
1241
1242
1243 firmware_map_add_hotplug(start, start + size, "System RAM");
1244
1245 goto out;
1246
1247error:
1248
1249 if (new_pgdat)
1250 rollback_node_hotadd(nid, pgdat);
1251 release_memory_resource(res);
1252
1253out:
1254 mem_hotplug_done();
1255 return ret;
1256}
1257EXPORT_SYMBOL_GPL(add_memory);
1258
1259#ifdef CONFIG_MEMORY_HOTREMOVE
1260
1261
1262
1263
1264
1265
1266
1267static inline int pageblock_free(struct page *page)
1268{
1269 return PageBuddy(page) && page_order(page) >= pageblock_order;
1270}
1271
1272
1273static struct page *next_active_pageblock(struct page *page)
1274{
1275
1276 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
1277
1278
1279 if (pageblock_free(page)) {
1280 int order;
1281
1282 order = page_order(page);
1283 if ((order < MAX_ORDER) && (order >= pageblock_order))
1284 return page + (1 << order);
1285 }
1286
1287 return page + pageblock_nr_pages;
1288}
1289
1290
1291int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
1292{
1293 struct page *page = pfn_to_page(start_pfn);
1294 struct page *end_page = page + nr_pages;
1295
1296
1297 for (; page < end_page; page = next_active_pageblock(page)) {
1298 if (!is_pageblock_removable_nolock(page))
1299 return 0;
1300 cond_resched();
1301 }
1302
1303
1304 return 1;
1305}
1306
1307
1308
1309
1310static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
1311{
1312 unsigned long pfn;
1313 struct zone *zone = NULL;
1314 struct page *page;
1315 int i;
1316 for (pfn = start_pfn;
1317 pfn < end_pfn;
1318 pfn += MAX_ORDER_NR_PAGES) {
1319 i = 0;
1320
1321 while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i))
1322 i++;
1323 if (i == MAX_ORDER_NR_PAGES)
1324 continue;
1325 page = pfn_to_page(pfn + i);
1326 if (zone && page_zone(page) != zone)
1327 return 0;
1328 zone = page_zone(page);
1329 }
1330 return 1;
1331}
1332
1333
1334
1335
1336
1337
1338
1339static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
1340{
1341 unsigned long pfn;
1342 struct page *page;
1343 for (pfn = start; pfn < end; pfn++) {
1344 if (pfn_valid(pfn)) {
1345 page = pfn_to_page(pfn);
1346 if (PageLRU(page))
1347 return pfn;
1348 if (PageHuge(page)) {
1349 if (is_hugepage_active(page))
1350 return pfn;
1351 else
1352 pfn = round_up(pfn + 1,
1353 1 << compound_order(page)) - 1;
1354 }
1355 }
1356 }
1357 return 0;
1358}
1359
1360#define NR_OFFLINE_AT_ONCE_PAGES (256)
1361static int
1362do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
1363{
1364 unsigned long pfn;
1365 struct page *page;
1366 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
1367 int not_managed = 0;
1368 int ret = 0;
1369 LIST_HEAD(source);
1370
1371 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
1372 if (!pfn_valid(pfn))
1373 continue;
1374 page = pfn_to_page(pfn);
1375
1376 if (PageHuge(page)) {
1377 struct page *head = compound_head(page);
1378 pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1;
1379 if (compound_order(head) > PFN_SECTION_SHIFT) {
1380 ret = -EBUSY;
1381 break;
1382 }
1383 if (isolate_huge_page(page, &source))
1384 move_pages -= 1 << compound_order(head);
1385 continue;
1386 }
1387
1388 if (!get_page_unless_zero(page))
1389 continue;
1390
1391
1392
1393
1394 ret = isolate_lru_page(page);
1395 if (!ret) {
1396 put_page(page);
1397 list_add_tail(&page->lru, &source);
1398 move_pages--;
1399 inc_zone_page_state(page, NR_ISOLATED_ANON +
1400 page_is_file_cache(page));
1401
1402 } else {
1403#ifdef CONFIG_DEBUG_VM
1404 printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
1405 pfn);
1406 dump_page(page, "failed to remove from LRU");
1407#endif
1408 put_page(page);
1409
1410
1411 if (page_count(page)) {
1412 not_managed++;
1413 ret = -EBUSY;
1414 break;
1415 }
1416 }
1417 }
1418 if (!list_empty(&source)) {
1419 if (not_managed) {
1420 putback_movable_pages(&source);
1421 goto out;
1422 }
1423
1424
1425
1426
1427
1428 ret = migrate_pages(&source, alloc_migrate_target, NULL, 0,
1429 MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
1430 if (ret)
1431 putback_movable_pages(&source);
1432 }
1433out:
1434 return ret;
1435}
1436
1437
1438
1439
1440static int
1441offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
1442 void *data)
1443{
1444 __offline_isolated_pages(start, start + nr_pages);
1445 return 0;
1446}
1447
1448static void
1449offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
1450{
1451 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
1452 offline_isolated_pages_cb);
1453}
1454
1455
1456
1457
1458static int
1459check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
1460 void *data)
1461{
1462 int ret;
1463 long offlined = *(long *)data;
1464 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
1465 offlined = nr_pages;
1466 if (!ret)
1467 *(long *)data += offlined;
1468 return ret;
1469}
1470
1471static long
1472check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
1473{
1474 long offlined = 0;
1475 int ret;
1476
1477 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
1478 check_pages_isolated_cb);
1479 if (ret < 0)
1480 offlined = (long)ret;
1481 return offlined;
1482}
1483
1484#ifdef CONFIG_MOVABLE_NODE
1485
1486
1487
1488
1489static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1490{
1491 return true;
1492}
1493#else
1494
1495static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1496{
1497 struct pglist_data *pgdat = zone->zone_pgdat;
1498 unsigned long present_pages = 0;
1499 enum zone_type zt;
1500
1501 for (zt = 0; zt <= ZONE_NORMAL; zt++)
1502 present_pages += pgdat->node_zones[zt].present_pages;
1503
1504 if (present_pages > nr_pages)
1505 return true;
1506
1507 present_pages = 0;
1508 for (; zt <= ZONE_MOVABLE; zt++)
1509 present_pages += pgdat->node_zones[zt].present_pages;
1510
1511
1512
1513
1514
1515 return present_pages == 0;
1516}
1517#endif
1518
1519static int __init cmdline_parse_movable_node(char *p)
1520{
1521#ifdef CONFIG_MOVABLE_NODE
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541 memblock_set_bottom_up(true);
1542 movable_node_enabled = true;
1543#else
1544 pr_warn("movable_node option not supported\n");
1545#endif
1546 return 0;
1547}
1548early_param("movable_node", cmdline_parse_movable_node);
1549
1550
1551static void node_states_check_changes_offline(unsigned long nr_pages,
1552 struct zone *zone, struct memory_notify *arg)
1553{
1554 struct pglist_data *pgdat = zone->zone_pgdat;
1555 unsigned long present_pages = 0;
1556 enum zone_type zt, zone_last = ZONE_NORMAL;
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567 if (N_MEMORY == N_NORMAL_MEMORY)
1568 zone_last = ZONE_MOVABLE;
1569
1570
1571
1572
1573
1574
1575
1576
1577 for (zt = 0; zt <= zone_last; zt++)
1578 present_pages += pgdat->node_zones[zt].present_pages;
1579 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1580 arg->status_change_nid_normal = zone_to_nid(zone);
1581 else
1582 arg->status_change_nid_normal = -1;
1583
1584#ifdef CONFIG_HIGHMEM
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594 zone_last = ZONE_HIGHMEM;
1595 if (N_MEMORY == N_HIGH_MEMORY)
1596 zone_last = ZONE_MOVABLE;
1597
1598 for (; zt <= zone_last; zt++)
1599 present_pages += pgdat->node_zones[zt].present_pages;
1600 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1601 arg->status_change_nid_high = zone_to_nid(zone);
1602 else
1603 arg->status_change_nid_high = -1;
1604#else
1605 arg->status_change_nid_high = arg->status_change_nid_normal;
1606#endif
1607
1608
1609
1610
1611 zone_last = ZONE_MOVABLE;
1612
1613
1614
1615
1616
1617
1618
1619 for (; zt <= zone_last; zt++)
1620 present_pages += pgdat->node_zones[zt].present_pages;
1621 if (nr_pages >= present_pages)
1622 arg->status_change_nid = zone_to_nid(zone);
1623 else
1624 arg->status_change_nid = -1;
1625}
1626
1627static void node_states_clear_node(int node, struct memory_notify *arg)
1628{
1629 if (arg->status_change_nid_normal >= 0)
1630 node_clear_state(node, N_NORMAL_MEMORY);
1631
1632 if ((N_MEMORY != N_NORMAL_MEMORY) &&
1633 (arg->status_change_nid_high >= 0))
1634 node_clear_state(node, N_HIGH_MEMORY);
1635
1636 if ((N_MEMORY != N_HIGH_MEMORY) &&
1637 (arg->status_change_nid >= 0))
1638 node_clear_state(node, N_MEMORY);
1639}
1640
1641static int __ref __offline_pages(unsigned long start_pfn,
1642 unsigned long end_pfn, unsigned long timeout)
1643{
1644 unsigned long pfn, nr_pages, expire;
1645 long offlined_pages;
1646 int ret, drain, retry_max, node;
1647 unsigned long flags;
1648 struct zone *zone;
1649 struct memory_notify arg;
1650
1651
1652 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
1653 return -EINVAL;
1654 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
1655 return -EINVAL;
1656
1657
1658 if (!test_pages_in_a_zone(start_pfn, end_pfn))
1659 return -EINVAL;
1660
1661 mem_hotplug_begin();
1662
1663 zone = page_zone(pfn_to_page(start_pfn));
1664 node = zone_to_nid(zone);
1665 nr_pages = end_pfn - start_pfn;
1666
1667 ret = -EINVAL;
1668 if (zone_idx(zone) <= ZONE_NORMAL && !can_offline_normal(zone, nr_pages))
1669 goto out;
1670
1671
1672 ret = start_isolate_page_range(start_pfn, end_pfn,
1673 MIGRATE_MOVABLE, true);
1674 if (ret)
1675 goto out;
1676
1677 arg.start_pfn = start_pfn;
1678 arg.nr_pages = nr_pages;
1679 node_states_check_changes_offline(nr_pages, zone, &arg);
1680
1681 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
1682 ret = notifier_to_errno(ret);
1683 if (ret)
1684 goto failed_removal;
1685
1686 pfn = start_pfn;
1687 expire = jiffies + timeout;
1688 drain = 0;
1689 retry_max = 5;
1690repeat:
1691
1692 ret = -EAGAIN;
1693 if (time_after(jiffies, expire))
1694 goto failed_removal;
1695 ret = -EINTR;
1696 if (signal_pending(current))
1697 goto failed_removal;
1698 ret = 0;
1699 if (drain) {
1700 lru_add_drain_all();
1701 cond_resched();
1702 drain_all_pages();
1703 }
1704
1705 pfn = scan_movable_pages(start_pfn, end_pfn);
1706 if (pfn) {
1707 ret = do_migrate_range(pfn, end_pfn);
1708 if (!ret) {
1709 drain = 1;
1710 goto repeat;
1711 } else {
1712 if (ret < 0)
1713 if (--retry_max == 0)
1714 goto failed_removal;
1715 yield();
1716 drain = 1;
1717 goto repeat;
1718 }
1719 }
1720
1721 lru_add_drain_all();
1722 yield();
1723
1724 drain_all_pages();
1725
1726
1727
1728
1729 dissolve_free_huge_pages(start_pfn, end_pfn);
1730
1731 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
1732 if (offlined_pages < 0) {
1733 ret = -EBUSY;
1734 goto failed_removal;
1735 }
1736 printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
1737
1738
1739 offline_isolated_pages(start_pfn, end_pfn);
1740
1741 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1742
1743 adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
1744 zone->present_pages -= offlined_pages;
1745
1746 pgdat_resize_lock(zone->zone_pgdat, &flags);
1747 zone->zone_pgdat->node_present_pages -= offlined_pages;
1748 pgdat_resize_unlock(zone->zone_pgdat, &flags);
1749
1750 init_per_zone_wmark_min();
1751
1752 if (!populated_zone(zone)) {
1753 zone_pcp_reset(zone);
1754 mutex_lock(&zonelists_mutex);
1755 build_all_zonelists(NULL, NULL);
1756 mutex_unlock(&zonelists_mutex);
1757 } else
1758 zone_pcp_update(zone);
1759
1760 node_states_clear_node(node, &arg);
1761 if (arg.status_change_nid >= 0)
1762 kswapd_stop(node);
1763
1764 vm_total_pages = nr_free_pagecache_pages();
1765 writeback_set_ratelimit();
1766
1767 memory_notify(MEM_OFFLINE, &arg);
1768 mem_hotplug_done();
1769 return 0;
1770
1771failed_removal:
1772 printk(KERN_INFO "memory offlining [mem %#010llx-%#010llx] failed\n",
1773 (unsigned long long) start_pfn << PAGE_SHIFT,
1774 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
1775 memory_notify(MEM_CANCEL_OFFLINE, &arg);
1776
1777 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1778
1779out:
1780 mem_hotplug_done();
1781 return ret;
1782}
1783
1784int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
1785{
1786 return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
1787}
1788#endif
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
1803 void *arg, int (*func)(struct memory_block *, void *))
1804{
1805 struct memory_block *mem = NULL;
1806 struct mem_section *section;
1807 unsigned long pfn, section_nr;
1808 int ret;
1809
1810 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1811 section_nr = pfn_to_section_nr(pfn);
1812 if (!present_section_nr(section_nr))
1813 continue;
1814
1815 section = __nr_to_section(section_nr);
1816
1817 if (mem)
1818 if ((section_nr >= mem->start_section_nr) &&
1819 (section_nr <= mem->end_section_nr))
1820 continue;
1821
1822 mem = find_memory_block_hinted(section, mem);
1823 if (!mem)
1824 continue;
1825
1826 ret = func(mem, arg);
1827 if (ret) {
1828 kobject_put(&mem->dev.kobj);
1829 return ret;
1830 }
1831 }
1832
1833 if (mem)
1834 kobject_put(&mem->dev.kobj);
1835
1836 return 0;
1837}
1838
1839#ifdef CONFIG_MEMORY_HOTREMOVE
1840static int check_memblock_offlined_cb(struct memory_block *mem, void *arg)
1841{
1842 int ret = !is_memblock_offlined(mem);
1843
1844 if (unlikely(ret)) {
1845 phys_addr_t beginpa, endpa;
1846
1847 beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr));
1848 endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1;
1849 pr_warn("removing memory fails, because memory "
1850 "[%pa-%pa] is onlined\n",
1851 &beginpa, &endpa);
1852 }
1853
1854 return ret;
1855}
1856
1857static int check_cpu_on_node(pg_data_t *pgdat)
1858{
1859 int cpu;
1860
1861 for_each_present_cpu(cpu) {
1862 if (cpu_to_node(cpu) == pgdat->node_id)
1863
1864
1865
1866
1867 return -EBUSY;
1868 }
1869
1870 return 0;
1871}
1872
1873static void unmap_cpu_on_node(pg_data_t *pgdat)
1874{
1875#ifdef CONFIG_ACPI_NUMA
1876 int cpu;
1877
1878 for_each_possible_cpu(cpu)
1879 if (cpu_to_node(cpu) == pgdat->node_id)
1880 numa_clear_node(cpu);
1881#endif
1882}
1883
1884static int check_and_unmap_cpu_on_node(pg_data_t *pgdat)
1885{
1886 int ret;
1887
1888 ret = check_cpu_on_node(pgdat);
1889 if (ret)
1890 return ret;
1891
1892
1893
1894
1895
1896
1897 unmap_cpu_on_node(pgdat);
1898 return 0;
1899}
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909void try_offline_node(int nid)
1910{
1911 pg_data_t *pgdat = NODE_DATA(nid);
1912 unsigned long start_pfn = pgdat->node_start_pfn;
1913 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
1914 unsigned long pfn;
1915 struct page *pgdat_page = virt_to_page(pgdat);
1916 int i;
1917
1918 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1919 unsigned long section_nr = pfn_to_section_nr(pfn);
1920
1921 if (!present_section_nr(section_nr))
1922 continue;
1923
1924 if (pfn_to_nid(pfn) != nid)
1925 continue;
1926
1927
1928
1929
1930
1931 return;
1932 }
1933
1934 if (check_and_unmap_cpu_on_node(pgdat))
1935 return;
1936
1937
1938
1939
1940
1941 node_set_offline(nid);
1942 unregister_one_node(nid);
1943
1944 if (!PageSlab(pgdat_page) && !PageCompound(pgdat_page))
1945
1946 return;
1947
1948
1949 for (i = 0; i < MAX_NR_ZONES; i++) {
1950 struct zone *zone = pgdat->node_zones + i;
1951
1952
1953
1954
1955
1956 if (is_vmalloc_addr(zone->wait_table))
1957 vfree(zone->wait_table);
1958 }
1959
1960
1961
1962
1963
1964
1965
1966
1967 memset(pgdat, 0, sizeof(*pgdat));
1968}
1969EXPORT_SYMBOL(try_offline_node);
1970
1971
1972
1973
1974
1975
1976
1977
1978void __ref remove_memory(int nid, u64 start, u64 size)
1979{
1980 int ret;
1981
1982 BUG_ON(check_hotplug_memory_range(start, size));
1983
1984 mem_hotplug_begin();
1985
1986
1987
1988
1989
1990
1991 ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
1992 check_memblock_offlined_cb);
1993 if (ret)
1994 BUG();
1995
1996
1997 firmware_map_remove(start, start + size, "System RAM");
1998
1999 arch_remove_memory(start, size);
2000
2001 try_offline_node(nid);
2002
2003 mem_hotplug_done();
2004}
2005EXPORT_SYMBOL_GPL(remove_memory);
2006#endif
2007