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6
7#include <linux/stddef.h>
8#include <linux/mm.h>
9#include <linux/sched/signal.h>
10#include <linux/swap.h>
11#include <linux/interrupt.h>
12#include <linux/pagemap.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/memremap.h>
22#include <linux/memory_hotplug.h>
23#include <linux/highmem.h>
24#include <linux/vmalloc.h>
25#include <linux/ioport.h>
26#include <linux/delay.h>
27#include <linux/migrate.h>
28#include <linux/page-isolation.h>
29#include <linux/pfn.h>
30#include <linux/suspend.h>
31#include <linux/mm_inline.h>
32#include <linux/firmware-map.h>
33#include <linux/stop_machine.h>
34#include <linux/hugetlb.h>
35#include <linux/memblock.h>
36#include <linux/bootmem.h>
37#include <linux/compaction.h>
38
39#include <asm/tlbflush.h>
40
41#include "internal.h"
42
43
44
45
46
47
48
49
50static void generic_online_page(struct page *page);
51
52static online_page_callback_t online_page_callback = generic_online_page;
53static DEFINE_MUTEX(online_page_callback_lock);
54
55DEFINE_STATIC_PERCPU_RWSEM(mem_hotplug_lock);
56
57void get_online_mems(void)
58{
59 percpu_down_read(&mem_hotplug_lock);
60}
61
62void put_online_mems(void)
63{
64 percpu_up_read(&mem_hotplug_lock);
65}
66
67bool movable_node_enabled = false;
68
69#ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
70bool memhp_auto_online;
71#else
72bool memhp_auto_online = true;
73#endif
74EXPORT_SYMBOL_GPL(memhp_auto_online);
75
76static int __init setup_memhp_default_state(char *str)
77{
78 if (!strcmp(str, "online"))
79 memhp_auto_online = true;
80 else if (!strcmp(str, "offline"))
81 memhp_auto_online = false;
82
83 return 1;
84}
85__setup("memhp_default_state=", setup_memhp_default_state);
86
87void mem_hotplug_begin(void)
88{
89 cpus_read_lock();
90 percpu_down_write(&mem_hotplug_lock);
91}
92
93void mem_hotplug_done(void)
94{
95 percpu_up_write(&mem_hotplug_lock);
96 cpus_read_unlock();
97}
98
99
100static struct resource *register_memory_resource(u64 start, u64 size)
101{
102 struct resource *res, *conflict;
103 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
104 if (!res)
105 return ERR_PTR(-ENOMEM);
106
107 res->name = "System RAM";
108 res->start = start;
109 res->end = start + size - 1;
110 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
111 conflict = request_resource_conflict(&iomem_resource, res);
112 if (conflict) {
113 if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) {
114 pr_debug("Device unaddressable memory block "
115 "memory hotplug at %#010llx !\n",
116 (unsigned long long)start);
117 }
118 pr_debug("System RAM resource %pR cannot be added\n", res);
119 kfree(res);
120 return ERR_PTR(-EEXIST);
121 }
122 return res;
123}
124
125static void release_memory_resource(struct resource *res)
126{
127 if (!res)
128 return;
129 release_resource(res);
130 kfree(res);
131 return;
132}
133
134#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
135void get_page_bootmem(unsigned long info, struct page *page,
136 unsigned long type)
137{
138 page->freelist = (void *)type;
139 SetPagePrivate(page);
140 set_page_private(page, info);
141 page_ref_inc(page);
142}
143
144void put_page_bootmem(struct page *page)
145{
146 unsigned long type;
147
148 type = (unsigned long) page->freelist;
149 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
150 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
151
152 if (page_ref_dec_return(page) == 1) {
153 page->freelist = NULL;
154 ClearPagePrivate(page);
155 set_page_private(page, 0);
156 INIT_LIST_HEAD(&page->lru);
157 free_reserved_page(page);
158 }
159}
160
161#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
162#ifndef CONFIG_SPARSEMEM_VMEMMAP
163static void register_page_bootmem_info_section(unsigned long start_pfn)
164{
165 unsigned long *usemap, mapsize, section_nr, i;
166 struct mem_section *ms;
167 struct page *page, *memmap;
168
169 section_nr = pfn_to_section_nr(start_pfn);
170 ms = __nr_to_section(section_nr);
171
172
173 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
174
175
176
177
178
179 page = virt_to_page(memmap);
180 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
181 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
182
183
184 for (i = 0; i < mapsize; i++, page++)
185 get_page_bootmem(section_nr, page, SECTION_INFO);
186
187 usemap = ms->pageblock_flags;
188 page = virt_to_page(usemap);
189
190 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
191
192 for (i = 0; i < mapsize; i++, page++)
193 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
194
195}
196#else
197static void register_page_bootmem_info_section(unsigned long start_pfn)
198{
199 unsigned long *usemap, mapsize, section_nr, i;
200 struct mem_section *ms;
201 struct page *page, *memmap;
202
203 section_nr = pfn_to_section_nr(start_pfn);
204 ms = __nr_to_section(section_nr);
205
206 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
207
208 register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
209
210 usemap = ms->pageblock_flags;
211 page = virt_to_page(usemap);
212
213 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
214
215 for (i = 0; i < mapsize; i++, page++)
216 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
217}
218#endif
219
220void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
221{
222 unsigned long i, pfn, end_pfn, nr_pages;
223 int node = pgdat->node_id;
224 struct page *page;
225
226 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
227 page = virt_to_page(pgdat);
228
229 for (i = 0; i < nr_pages; i++, page++)
230 get_page_bootmem(node, page, NODE_INFO);
231
232 pfn = pgdat->node_start_pfn;
233 end_pfn = pgdat_end_pfn(pgdat);
234
235
236 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
237
238
239
240
241
242
243 if (pfn_valid(pfn) && (early_pfn_to_nid(pfn) == node))
244 register_page_bootmem_info_section(pfn);
245 }
246}
247#endif
248
249static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
250 struct vmem_altmap *altmap, bool want_memblock)
251{
252 int ret;
253
254 if (pfn_valid(phys_start_pfn))
255 return -EEXIST;
256
257 ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn, altmap);
258 if (ret < 0)
259 return ret;
260
261 if (!want_memblock)
262 return 0;
263
264 return hotplug_memory_register(nid, __pfn_to_section(phys_start_pfn));
265}
266
267
268
269
270
271
272
273int __ref __add_pages(int nid, unsigned long phys_start_pfn,
274 unsigned long nr_pages, struct vmem_altmap *altmap,
275 bool want_memblock)
276{
277 unsigned long i;
278 int err = 0;
279 int start_sec, end_sec;
280
281
282 start_sec = pfn_to_section_nr(phys_start_pfn);
283 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
284
285 if (altmap) {
286
287
288
289 if (altmap->base_pfn != phys_start_pfn
290 || vmem_altmap_offset(altmap) > nr_pages) {
291 pr_warn_once("memory add fail, invalid altmap\n");
292 err = -EINVAL;
293 goto out;
294 }
295 altmap->alloc = 0;
296 }
297
298 for (i = start_sec; i <= end_sec; i++) {
299 err = __add_section(nid, section_nr_to_pfn(i), altmap,
300 want_memblock);
301
302
303
304
305
306
307 if (err && (err != -EEXIST))
308 break;
309 err = 0;
310 cond_resched();
311 }
312 vmemmap_populate_print_last();
313out:
314 return err;
315}
316
317#ifdef CONFIG_MEMORY_HOTREMOVE
318
319static unsigned long find_smallest_section_pfn(int nid, struct zone *zone,
320 unsigned long start_pfn,
321 unsigned long end_pfn)
322{
323 struct mem_section *ms;
324
325 for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
326 ms = __pfn_to_section(start_pfn);
327
328 if (unlikely(!valid_section(ms)))
329 continue;
330
331 if (unlikely(pfn_to_nid(start_pfn) != nid))
332 continue;
333
334 if (zone && zone != page_zone(pfn_to_page(start_pfn)))
335 continue;
336
337 return start_pfn;
338 }
339
340 return 0;
341}
342
343
344static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
345 unsigned long start_pfn,
346 unsigned long end_pfn)
347{
348 struct mem_section *ms;
349 unsigned long pfn;
350
351
352 pfn = end_pfn - 1;
353 for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
354 ms = __pfn_to_section(pfn);
355
356 if (unlikely(!valid_section(ms)))
357 continue;
358
359 if (unlikely(pfn_to_nid(pfn) != nid))
360 continue;
361
362 if (zone && zone != page_zone(pfn_to_page(pfn)))
363 continue;
364
365 return pfn;
366 }
367
368 return 0;
369}
370
371static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
372 unsigned long end_pfn)
373{
374 unsigned long zone_start_pfn = zone->zone_start_pfn;
375 unsigned long z = zone_end_pfn(zone);
376 unsigned long zone_end_pfn = z;
377 unsigned long pfn;
378 struct mem_section *ms;
379 int nid = zone_to_nid(zone);
380
381 zone_span_writelock(zone);
382 if (zone_start_pfn == start_pfn) {
383
384
385
386
387
388
389 pfn = find_smallest_section_pfn(nid, zone, end_pfn,
390 zone_end_pfn);
391 if (pfn) {
392 zone->zone_start_pfn = pfn;
393 zone->spanned_pages = zone_end_pfn - pfn;
394 }
395 } else if (zone_end_pfn == end_pfn) {
396
397
398
399
400
401
402 pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
403 start_pfn);
404 if (pfn)
405 zone->spanned_pages = pfn - zone_start_pfn + 1;
406 }
407
408
409
410
411
412
413
414 pfn = zone_start_pfn;
415 for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
416 ms = __pfn_to_section(pfn);
417
418 if (unlikely(!valid_section(ms)))
419 continue;
420
421 if (page_zone(pfn_to_page(pfn)) != zone)
422 continue;
423
424
425 if (start_pfn == pfn)
426 continue;
427
428
429 zone_span_writeunlock(zone);
430 return;
431 }
432
433
434 zone->zone_start_pfn = 0;
435 zone->spanned_pages = 0;
436 zone_span_writeunlock(zone);
437}
438
439static void shrink_pgdat_span(struct pglist_data *pgdat,
440 unsigned long start_pfn, unsigned long end_pfn)
441{
442 unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
443 unsigned long p = pgdat_end_pfn(pgdat);
444 unsigned long pgdat_end_pfn = p;
445 unsigned long pfn;
446 struct mem_section *ms;
447 int nid = pgdat->node_id;
448
449 if (pgdat_start_pfn == start_pfn) {
450
451
452
453
454
455
456 pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
457 pgdat_end_pfn);
458 if (pfn) {
459 pgdat->node_start_pfn = pfn;
460 pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
461 }
462 } else if (pgdat_end_pfn == end_pfn) {
463
464
465
466
467
468
469 pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
470 start_pfn);
471 if (pfn)
472 pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
473 }
474
475
476
477
478
479
480
481
482 pfn = pgdat_start_pfn;
483 for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
484 ms = __pfn_to_section(pfn);
485
486 if (unlikely(!valid_section(ms)))
487 continue;
488
489 if (pfn_to_nid(pfn) != nid)
490 continue;
491
492
493 if (start_pfn == pfn)
494 continue;
495
496
497 return;
498 }
499
500
501 pgdat->node_start_pfn = 0;
502 pgdat->node_spanned_pages = 0;
503}
504
505static void __remove_zone(struct zone *zone, unsigned long start_pfn)
506{
507 struct pglist_data *pgdat = zone->zone_pgdat;
508 int nr_pages = PAGES_PER_SECTION;
509 unsigned long flags;
510
511 pgdat_resize_lock(zone->zone_pgdat, &flags);
512 shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
513 shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
514 pgdat_resize_unlock(zone->zone_pgdat, &flags);
515}
516
517static int __remove_section(struct zone *zone, struct mem_section *ms,
518 unsigned long map_offset, struct vmem_altmap *altmap)
519{
520 unsigned long start_pfn;
521 int scn_nr;
522 int ret = -EINVAL;
523
524 if (!valid_section(ms))
525 return ret;
526
527 ret = unregister_memory_section(ms);
528 if (ret)
529 return ret;
530
531 scn_nr = __section_nr(ms);
532 start_pfn = section_nr_to_pfn((unsigned long)scn_nr);
533 __remove_zone(zone, start_pfn);
534
535 sparse_remove_one_section(zone, ms, map_offset, altmap);
536 return 0;
537}
538
539
540
541
542
543
544
545
546
547
548
549
550
551int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
552 unsigned long nr_pages, struct vmem_altmap *altmap)
553{
554 unsigned long i;
555 unsigned long map_offset = 0;
556 int sections_to_remove, ret = 0;
557
558
559 if (is_dev_zone(zone)) {
560 if (altmap)
561 map_offset = vmem_altmap_offset(altmap);
562 } else {
563 resource_size_t start, size;
564
565 start = phys_start_pfn << PAGE_SHIFT;
566 size = nr_pages * PAGE_SIZE;
567
568 ret = release_mem_region_adjustable(&iomem_resource, start,
569 size);
570 if (ret) {
571 resource_size_t endres = start + size - 1;
572
573 pr_warn("Unable to release resource <%pa-%pa> (%d)\n",
574 &start, &endres, ret);
575 }
576 }
577
578 clear_zone_contiguous(zone);
579
580
581
582
583 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
584 BUG_ON(nr_pages % PAGES_PER_SECTION);
585
586 sections_to_remove = nr_pages / PAGES_PER_SECTION;
587 for (i = 0; i < sections_to_remove; i++) {
588 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
589
590 ret = __remove_section(zone, __pfn_to_section(pfn), map_offset,
591 altmap);
592 map_offset = 0;
593 if (ret)
594 break;
595 }
596
597 set_zone_contiguous(zone);
598
599 return ret;
600}
601#endif
602
603int set_online_page_callback(online_page_callback_t callback)
604{
605 int rc = -EINVAL;
606
607 get_online_mems();
608 mutex_lock(&online_page_callback_lock);
609
610 if (online_page_callback == generic_online_page) {
611 online_page_callback = callback;
612 rc = 0;
613 }
614
615 mutex_unlock(&online_page_callback_lock);
616 put_online_mems();
617
618 return rc;
619}
620EXPORT_SYMBOL_GPL(set_online_page_callback);
621
622int restore_online_page_callback(online_page_callback_t callback)
623{
624 int rc = -EINVAL;
625
626 get_online_mems();
627 mutex_lock(&online_page_callback_lock);
628
629 if (online_page_callback == callback) {
630 online_page_callback = generic_online_page;
631 rc = 0;
632 }
633
634 mutex_unlock(&online_page_callback_lock);
635 put_online_mems();
636
637 return rc;
638}
639EXPORT_SYMBOL_GPL(restore_online_page_callback);
640
641void __online_page_set_limits(struct page *page)
642{
643}
644EXPORT_SYMBOL_GPL(__online_page_set_limits);
645
646void __online_page_increment_counters(struct page *page)
647{
648 adjust_managed_page_count(page, 1);
649}
650EXPORT_SYMBOL_GPL(__online_page_increment_counters);
651
652void __online_page_free(struct page *page)
653{
654 __free_reserved_page(page);
655}
656EXPORT_SYMBOL_GPL(__online_page_free);
657
658static void generic_online_page(struct page *page)
659{
660 __online_page_set_limits(page);
661 __online_page_increment_counters(page);
662 __online_page_free(page);
663}
664
665static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
666 void *arg)
667{
668 unsigned long i;
669 unsigned long onlined_pages = *(unsigned long *)arg;
670 struct page *page;
671
672 if (PageReserved(pfn_to_page(start_pfn)))
673 for (i = 0; i < nr_pages; i++) {
674 page = pfn_to_page(start_pfn + i);
675 (*online_page_callback)(page);
676 onlined_pages++;
677 }
678
679 online_mem_sections(start_pfn, start_pfn + nr_pages);
680
681 *(unsigned long *)arg = onlined_pages;
682 return 0;
683}
684
685
686static void node_states_check_changes_online(unsigned long nr_pages,
687 struct zone *zone, struct memory_notify *arg)
688{
689 int nid = zone_to_nid(zone);
690 enum zone_type zone_last = ZONE_NORMAL;
691
692
693
694
695
696
697
698
699
700
701 if (N_MEMORY == N_NORMAL_MEMORY)
702 zone_last = ZONE_MOVABLE;
703
704
705
706
707
708
709
710 if (zone_idx(zone) <= zone_last && !node_state(nid, N_NORMAL_MEMORY))
711 arg->status_change_nid_normal = nid;
712 else
713 arg->status_change_nid_normal = -1;
714
715#ifdef CONFIG_HIGHMEM
716
717
718
719
720
721
722
723
724
725 zone_last = ZONE_HIGHMEM;
726 if (N_MEMORY == N_HIGH_MEMORY)
727 zone_last = ZONE_MOVABLE;
728
729 if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
730 arg->status_change_nid_high = nid;
731 else
732 arg->status_change_nid_high = -1;
733#else
734 arg->status_change_nid_high = arg->status_change_nid_normal;
735#endif
736
737
738
739
740
741
742 if (!node_state(nid, N_MEMORY))
743 arg->status_change_nid = nid;
744 else
745 arg->status_change_nid = -1;
746}
747
748static void node_states_set_node(int node, struct memory_notify *arg)
749{
750 if (arg->status_change_nid_normal >= 0)
751 node_set_state(node, N_NORMAL_MEMORY);
752
753 if (arg->status_change_nid_high >= 0)
754 node_set_state(node, N_HIGH_MEMORY);
755
756 node_set_state(node, N_MEMORY);
757}
758
759static void __meminit resize_zone_range(struct zone *zone, unsigned long start_pfn,
760 unsigned long nr_pages)
761{
762 unsigned long old_end_pfn = zone_end_pfn(zone);
763
764 if (zone_is_empty(zone) || start_pfn < zone->zone_start_pfn)
765 zone->zone_start_pfn = start_pfn;
766
767 zone->spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - zone->zone_start_pfn;
768}
769
770static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned long start_pfn,
771 unsigned long nr_pages)
772{
773 unsigned long old_end_pfn = pgdat_end_pfn(pgdat);
774
775 if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
776 pgdat->node_start_pfn = start_pfn;
777
778 pgdat->node_spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - pgdat->node_start_pfn;
779}
780
781void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
782 unsigned long nr_pages, struct vmem_altmap *altmap)
783{
784 struct pglist_data *pgdat = zone->zone_pgdat;
785 int nid = pgdat->node_id;
786 unsigned long flags;
787
788 if (zone_is_empty(zone))
789 init_currently_empty_zone(zone, start_pfn, nr_pages);
790
791 clear_zone_contiguous(zone);
792
793
794 pgdat_resize_lock(pgdat, &flags);
795 zone_span_writelock(zone);
796 resize_zone_range(zone, start_pfn, nr_pages);
797 zone_span_writeunlock(zone);
798 resize_pgdat_range(pgdat, start_pfn, nr_pages);
799 pgdat_resize_unlock(pgdat, &flags);
800
801
802
803
804
805
806
807 memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn,
808 MEMMAP_HOTPLUG, altmap);
809
810 set_zone_contiguous(zone);
811}
812
813
814
815
816
817
818static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn,
819 unsigned long nr_pages)
820{
821 struct pglist_data *pgdat = NODE_DATA(nid);
822 int zid;
823
824 for (zid = 0; zid <= ZONE_NORMAL; zid++) {
825 struct zone *zone = &pgdat->node_zones[zid];
826
827 if (zone_intersects(zone, start_pfn, nr_pages))
828 return zone;
829 }
830
831 return &pgdat->node_zones[ZONE_NORMAL];
832}
833
834static inline struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn,
835 unsigned long nr_pages)
836{
837 struct zone *kernel_zone = default_kernel_zone_for_pfn(nid, start_pfn,
838 nr_pages);
839 struct zone *movable_zone = &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
840 bool in_kernel = zone_intersects(kernel_zone, start_pfn, nr_pages);
841 bool in_movable = zone_intersects(movable_zone, start_pfn, nr_pages);
842
843
844
845
846
847 if (in_kernel ^ in_movable)
848 return (in_kernel) ? kernel_zone : movable_zone;
849
850
851
852
853
854
855 return movable_node_enabled ? movable_zone : kernel_zone;
856}
857
858struct zone * zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
859 unsigned long nr_pages)
860{
861 if (online_type == MMOP_ONLINE_KERNEL)
862 return default_kernel_zone_for_pfn(nid, start_pfn, nr_pages);
863
864 if (online_type == MMOP_ONLINE_MOVABLE)
865 return &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
866
867 return default_zone_for_pfn(nid, start_pfn, nr_pages);
868}
869
870
871
872
873
874static struct zone * __meminit move_pfn_range(int online_type, int nid,
875 unsigned long start_pfn, unsigned long nr_pages)
876{
877 struct zone *zone;
878
879 zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
880 move_pfn_range_to_zone(zone, start_pfn, nr_pages, NULL);
881 return zone;
882}
883
884
885int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
886{
887 unsigned long flags;
888 unsigned long onlined_pages = 0;
889 struct zone *zone;
890 int need_zonelists_rebuild = 0;
891 int nid;
892 int ret;
893 struct memory_notify arg;
894 struct memory_block *mem;
895
896
897
898
899
900 mem = find_memory_block(__pfn_to_section(pfn));
901 nid = mem->nid;
902
903
904 zone = move_pfn_range(online_type, nid, pfn, nr_pages);
905
906 arg.start_pfn = pfn;
907 arg.nr_pages = nr_pages;
908 node_states_check_changes_online(nr_pages, zone, &arg);
909
910 ret = memory_notify(MEM_GOING_ONLINE, &arg);
911 ret = notifier_to_errno(ret);
912 if (ret)
913 goto failed_addition;
914
915
916
917
918
919
920 if (!populated_zone(zone)) {
921 need_zonelists_rebuild = 1;
922 setup_zone_pageset(zone);
923 }
924
925 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
926 online_pages_range);
927 if (ret) {
928 if (need_zonelists_rebuild)
929 zone_pcp_reset(zone);
930 goto failed_addition;
931 }
932
933 zone->present_pages += onlined_pages;
934
935 pgdat_resize_lock(zone->zone_pgdat, &flags);
936 zone->zone_pgdat->node_present_pages += onlined_pages;
937 pgdat_resize_unlock(zone->zone_pgdat, &flags);
938
939 if (onlined_pages) {
940 node_states_set_node(nid, &arg);
941 if (need_zonelists_rebuild)
942 build_all_zonelists(NULL);
943 else
944 zone_pcp_update(zone);
945 }
946
947 init_per_zone_wmark_min();
948
949 if (onlined_pages) {
950 kswapd_run(nid);
951 kcompactd_run(nid);
952 }
953
954 vm_total_pages = nr_free_pagecache_pages();
955
956 writeback_set_ratelimit();
957
958 if (onlined_pages)
959 memory_notify(MEM_ONLINE, &arg);
960 return 0;
961
962failed_addition:
963 pr_debug("online_pages [mem %#010llx-%#010llx] failed\n",
964 (unsigned long long) pfn << PAGE_SHIFT,
965 (((unsigned long long) pfn + nr_pages) << PAGE_SHIFT) - 1);
966 memory_notify(MEM_CANCEL_ONLINE, &arg);
967 return ret;
968}
969#endif
970
971static void reset_node_present_pages(pg_data_t *pgdat)
972{
973 struct zone *z;
974
975 for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
976 z->present_pages = 0;
977
978 pgdat->node_present_pages = 0;
979}
980
981
982static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
983{
984 struct pglist_data *pgdat;
985 unsigned long zones_size[MAX_NR_ZONES] = {0};
986 unsigned long zholes_size[MAX_NR_ZONES] = {0};
987 unsigned long start_pfn = PFN_DOWN(start);
988
989 pgdat = NODE_DATA(nid);
990 if (!pgdat) {
991 pgdat = arch_alloc_nodedata(nid);
992 if (!pgdat)
993 return NULL;
994
995 arch_refresh_nodedata(nid, pgdat);
996 } else {
997
998
999
1000
1001
1002 pgdat->nr_zones = 0;
1003 pgdat->kswapd_order = 0;
1004 pgdat->kswapd_classzone_idx = 0;
1005 }
1006
1007
1008
1009
1010 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
1011 pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
1012
1013
1014
1015
1016
1017 build_all_zonelists(pgdat);
1018
1019
1020
1021
1022
1023
1024
1025 reset_node_managed_pages(pgdat);
1026
1027
1028
1029
1030
1031
1032 reset_node_present_pages(pgdat);
1033
1034 return pgdat;
1035}
1036
1037static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
1038{
1039 arch_refresh_nodedata(nid, NULL);
1040 free_percpu(pgdat->per_cpu_nodestats);
1041 arch_free_nodedata(pgdat);
1042 return;
1043}
1044
1045
1046
1047
1048
1049
1050
1051
1052int try_online_node(int nid)
1053{
1054 pg_data_t *pgdat;
1055 int ret;
1056
1057 if (node_online(nid))
1058 return 0;
1059
1060 mem_hotplug_begin();
1061 pgdat = hotadd_new_pgdat(nid, 0);
1062 if (!pgdat) {
1063 pr_err("Cannot online node %d due to NULL pgdat\n", nid);
1064 ret = -ENOMEM;
1065 goto out;
1066 }
1067 node_set_online(nid);
1068 ret = register_one_node(nid);
1069 BUG_ON(ret);
1070out:
1071 mem_hotplug_done();
1072 return ret;
1073}
1074
1075static int check_hotplug_memory_range(u64 start, u64 size)
1076{
1077 unsigned long block_sz = memory_block_size_bytes();
1078 u64 block_nr_pages = block_sz >> PAGE_SHIFT;
1079 u64 nr_pages = size >> PAGE_SHIFT;
1080 u64 start_pfn = PFN_DOWN(start);
1081
1082
1083 if (!nr_pages || !IS_ALIGNED(start_pfn, block_nr_pages) ||
1084 !IS_ALIGNED(nr_pages, block_nr_pages)) {
1085 pr_err("Block size [%#lx] unaligned hotplug range: start %#llx, size %#llx",
1086 block_sz, start, size);
1087 return -EINVAL;
1088 }
1089
1090 return 0;
1091}
1092
1093static int online_memory_block(struct memory_block *mem, void *arg)
1094{
1095 return device_online(&mem->dev);
1096}
1097
1098
1099int __ref add_memory_resource(int nid, struct resource *res, bool online)
1100{
1101 u64 start, size;
1102 pg_data_t *pgdat = NULL;
1103 bool new_pgdat;
1104 bool new_node;
1105 int ret;
1106
1107 start = res->start;
1108 size = resource_size(res);
1109
1110 ret = check_hotplug_memory_range(start, size);
1111 if (ret)
1112 return ret;
1113
1114 {
1115 void *p = NODE_DATA(nid);
1116 new_pgdat = !p;
1117 }
1118
1119 mem_hotplug_begin();
1120
1121
1122
1123
1124
1125
1126
1127 memblock_add_node(start, size, nid);
1128
1129 new_node = !node_online(nid);
1130 if (new_node) {
1131 pgdat = hotadd_new_pgdat(nid, start);
1132 ret = -ENOMEM;
1133 if (!pgdat)
1134 goto error;
1135 }
1136
1137
1138 ret = arch_add_memory(nid, start, size, NULL, true);
1139
1140 if (ret < 0)
1141 goto error;
1142
1143
1144 node_set_online(nid);
1145
1146 if (new_node) {
1147 unsigned long start_pfn = start >> PAGE_SHIFT;
1148 unsigned long nr_pages = size >> PAGE_SHIFT;
1149
1150 ret = __register_one_node(nid);
1151 if (ret)
1152 goto register_fail;
1153
1154
1155
1156
1157
1158
1159
1160
1161 ret = link_mem_sections(nid, start_pfn, nr_pages, false);
1162register_fail:
1163
1164
1165
1166
1167
1168 BUG_ON(ret);
1169 }
1170
1171
1172 firmware_map_add_hotplug(start, start + size, "System RAM");
1173
1174
1175 if (online)
1176 walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1),
1177 NULL, online_memory_block);
1178
1179 goto out;
1180
1181error:
1182
1183 if (new_pgdat && pgdat)
1184 rollback_node_hotadd(nid, pgdat);
1185 memblock_remove(start, size);
1186
1187out:
1188 mem_hotplug_done();
1189 return ret;
1190}
1191EXPORT_SYMBOL_GPL(add_memory_resource);
1192
1193int __ref add_memory(int nid, u64 start, u64 size)
1194{
1195 struct resource *res;
1196 int ret;
1197
1198 res = register_memory_resource(start, size);
1199 if (IS_ERR(res))
1200 return PTR_ERR(res);
1201
1202 ret = add_memory_resource(nid, res, memhp_auto_online);
1203 if (ret < 0)
1204 release_memory_resource(res);
1205 return ret;
1206}
1207EXPORT_SYMBOL_GPL(add_memory);
1208
1209#ifdef CONFIG_MEMORY_HOTREMOVE
1210
1211
1212
1213
1214
1215
1216
1217static inline int pageblock_free(struct page *page)
1218{
1219 return PageBuddy(page) && page_order(page) >= pageblock_order;
1220}
1221
1222
1223static struct page *next_active_pageblock(struct page *page)
1224{
1225
1226 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
1227
1228
1229 if (pageblock_free(page)) {
1230 int order;
1231
1232 order = page_order(page);
1233 if ((order < MAX_ORDER) && (order >= pageblock_order))
1234 return page + (1 << order);
1235 }
1236
1237 return page + pageblock_nr_pages;
1238}
1239
1240
1241bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
1242{
1243 struct page *page = pfn_to_page(start_pfn);
1244 struct page *end_page = page + nr_pages;
1245
1246
1247 for (; page < end_page; page = next_active_pageblock(page)) {
1248 if (!is_pageblock_removable_nolock(page))
1249 return false;
1250 cond_resched();
1251 }
1252
1253
1254 return true;
1255}
1256
1257
1258
1259
1260
1261int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
1262 unsigned long *valid_start, unsigned long *valid_end)
1263{
1264 unsigned long pfn, sec_end_pfn;
1265 unsigned long start, end;
1266 struct zone *zone = NULL;
1267 struct page *page;
1268 int i;
1269 for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn + 1);
1270 pfn < end_pfn;
1271 pfn = sec_end_pfn, sec_end_pfn += PAGES_PER_SECTION) {
1272
1273 if (!present_section_nr(pfn_to_section_nr(pfn)))
1274 continue;
1275 for (; pfn < sec_end_pfn && pfn < end_pfn;
1276 pfn += MAX_ORDER_NR_PAGES) {
1277 i = 0;
1278
1279 while ((i < MAX_ORDER_NR_PAGES) &&
1280 !pfn_valid_within(pfn + i))
1281 i++;
1282 if (i == MAX_ORDER_NR_PAGES || pfn + i >= end_pfn)
1283 continue;
1284 page = pfn_to_page(pfn + i);
1285 if (zone && page_zone(page) != zone)
1286 return 0;
1287 if (!zone)
1288 start = pfn + i;
1289 zone = page_zone(page);
1290 end = pfn + MAX_ORDER_NR_PAGES;
1291 }
1292 }
1293
1294 if (zone) {
1295 *valid_start = start;
1296 *valid_end = min(end, end_pfn);
1297 return 1;
1298 } else {
1299 return 0;
1300 }
1301}
1302
1303
1304
1305
1306
1307
1308
1309static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
1310{
1311 unsigned long pfn;
1312 struct page *page;
1313 for (pfn = start; pfn < end; pfn++) {
1314 if (pfn_valid(pfn)) {
1315 page = pfn_to_page(pfn);
1316 if (PageLRU(page))
1317 return pfn;
1318 if (__PageMovable(page))
1319 return pfn;
1320 if (PageHuge(page)) {
1321 if (page_huge_active(page))
1322 return pfn;
1323 else
1324 pfn = round_up(pfn + 1,
1325 1 << compound_order(page)) - 1;
1326 }
1327 }
1328 }
1329 return 0;
1330}
1331
1332static struct page *new_node_page(struct page *page, unsigned long private)
1333{
1334 int nid = page_to_nid(page);
1335 nodemask_t nmask = node_states[N_MEMORY];
1336
1337
1338
1339
1340
1341
1342 node_clear(nid, nmask);
1343 if (nodes_empty(nmask))
1344 node_set(nid, nmask);
1345
1346 return new_page_nodemask(page, nid, &nmask);
1347}
1348
1349#define NR_OFFLINE_AT_ONCE_PAGES (256)
1350static int
1351do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
1352{
1353 unsigned long pfn;
1354 struct page *page;
1355 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
1356 int not_managed = 0;
1357 int ret = 0;
1358 LIST_HEAD(source);
1359
1360 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
1361 if (!pfn_valid(pfn))
1362 continue;
1363 page = pfn_to_page(pfn);
1364
1365 if (PageHuge(page)) {
1366 struct page *head = compound_head(page);
1367 pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1;
1368 if (compound_order(head) > PFN_SECTION_SHIFT) {
1369 ret = -EBUSY;
1370 break;
1371 }
1372 if (isolate_huge_page(page, &source))
1373 move_pages -= 1 << compound_order(head);
1374 continue;
1375 } else if (PageTransHuge(page))
1376 pfn = page_to_pfn(compound_head(page))
1377 + hpage_nr_pages(page) - 1;
1378
1379 if (!get_page_unless_zero(page))
1380 continue;
1381
1382
1383
1384
1385 if (PageLRU(page))
1386 ret = isolate_lru_page(page);
1387 else
1388 ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
1389 if (!ret) {
1390 put_page(page);
1391 list_add_tail(&page->lru, &source);
1392 move_pages--;
1393 if (!__PageMovable(page))
1394 inc_node_page_state(page, NR_ISOLATED_ANON +
1395 page_is_file_cache(page));
1396
1397 } else {
1398#ifdef CONFIG_DEBUG_VM
1399 pr_alert("failed to isolate pfn %lx\n", pfn);
1400 dump_page(page, "isolation failed");
1401#endif
1402 put_page(page);
1403
1404
1405 if (page_count(page)) {
1406 not_managed++;
1407 ret = -EBUSY;
1408 break;
1409 }
1410 }
1411 }
1412 if (!list_empty(&source)) {
1413 if (not_managed) {
1414 putback_movable_pages(&source);
1415 goto out;
1416 }
1417
1418
1419 ret = migrate_pages(&source, new_node_page, NULL, 0,
1420 MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
1421 if (ret)
1422 putback_movable_pages(&source);
1423 }
1424out:
1425 return ret;
1426}
1427
1428
1429
1430
1431static int
1432offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
1433 void *data)
1434{
1435 __offline_isolated_pages(start, start + nr_pages);
1436 return 0;
1437}
1438
1439static void
1440offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
1441{
1442 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
1443 offline_isolated_pages_cb);
1444}
1445
1446
1447
1448
1449static int
1450check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
1451 void *data)
1452{
1453 int ret;
1454 long offlined = *(long *)data;
1455 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
1456 offlined = nr_pages;
1457 if (!ret)
1458 *(long *)data += offlined;
1459 return ret;
1460}
1461
1462static long
1463check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
1464{
1465 long offlined = 0;
1466 int ret;
1467
1468 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
1469 check_pages_isolated_cb);
1470 if (ret < 0)
1471 offlined = (long)ret;
1472 return offlined;
1473}
1474
1475static int __init cmdline_parse_movable_node(char *p)
1476{
1477#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1478 movable_node_enabled = true;
1479#else
1480 pr_warn("movable_node parameter depends on CONFIG_HAVE_MEMBLOCK_NODE_MAP to work properly\n");
1481#endif
1482 return 0;
1483}
1484early_param("movable_node", cmdline_parse_movable_node);
1485
1486
1487static void node_states_check_changes_offline(unsigned long nr_pages,
1488 struct zone *zone, struct memory_notify *arg)
1489{
1490 struct pglist_data *pgdat = zone->zone_pgdat;
1491 unsigned long present_pages = 0;
1492 enum zone_type zt, zone_last = ZONE_NORMAL;
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503 if (N_MEMORY == N_NORMAL_MEMORY)
1504 zone_last = ZONE_MOVABLE;
1505
1506
1507
1508
1509
1510
1511
1512
1513 for (zt = 0; zt <= zone_last; zt++)
1514 present_pages += pgdat->node_zones[zt].present_pages;
1515 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1516 arg->status_change_nid_normal = zone_to_nid(zone);
1517 else
1518 arg->status_change_nid_normal = -1;
1519
1520#ifdef CONFIG_HIGHMEM
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530 zone_last = ZONE_HIGHMEM;
1531 if (N_MEMORY == N_HIGH_MEMORY)
1532 zone_last = ZONE_MOVABLE;
1533
1534 for (; zt <= zone_last; zt++)
1535 present_pages += pgdat->node_zones[zt].present_pages;
1536 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1537 arg->status_change_nid_high = zone_to_nid(zone);
1538 else
1539 arg->status_change_nid_high = -1;
1540#else
1541 arg->status_change_nid_high = arg->status_change_nid_normal;
1542#endif
1543
1544
1545
1546
1547 zone_last = ZONE_MOVABLE;
1548
1549
1550
1551
1552
1553
1554
1555 for (; zt <= zone_last; zt++)
1556 present_pages += pgdat->node_zones[zt].present_pages;
1557 if (nr_pages >= present_pages)
1558 arg->status_change_nid = zone_to_nid(zone);
1559 else
1560 arg->status_change_nid = -1;
1561}
1562
1563static void node_states_clear_node(int node, struct memory_notify *arg)
1564{
1565 if (arg->status_change_nid_normal >= 0)
1566 node_clear_state(node, N_NORMAL_MEMORY);
1567
1568 if ((N_MEMORY != N_NORMAL_MEMORY) &&
1569 (arg->status_change_nid_high >= 0))
1570 node_clear_state(node, N_HIGH_MEMORY);
1571
1572 if ((N_MEMORY != N_HIGH_MEMORY) &&
1573 (arg->status_change_nid >= 0))
1574 node_clear_state(node, N_MEMORY);
1575}
1576
1577static int __ref __offline_pages(unsigned long start_pfn,
1578 unsigned long end_pfn)
1579{
1580 unsigned long pfn, nr_pages;
1581 long offlined_pages;
1582 int ret, node;
1583 unsigned long flags;
1584 unsigned long valid_start, valid_end;
1585 struct zone *zone;
1586 struct memory_notify arg;
1587
1588
1589 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
1590 return -EINVAL;
1591 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
1592 return -EINVAL;
1593
1594
1595 if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
1596 return -EINVAL;
1597
1598 zone = page_zone(pfn_to_page(valid_start));
1599 node = zone_to_nid(zone);
1600 nr_pages = end_pfn - start_pfn;
1601
1602
1603 ret = start_isolate_page_range(start_pfn, end_pfn,
1604 MIGRATE_MOVABLE, true);
1605 if (ret)
1606 return ret;
1607
1608 arg.start_pfn = start_pfn;
1609 arg.nr_pages = nr_pages;
1610 node_states_check_changes_offline(nr_pages, zone, &arg);
1611
1612 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
1613 ret = notifier_to_errno(ret);
1614 if (ret)
1615 goto failed_removal;
1616
1617 pfn = start_pfn;
1618repeat:
1619
1620 ret = -EINTR;
1621 if (signal_pending(current))
1622 goto failed_removal;
1623
1624 cond_resched();
1625 lru_add_drain_all();
1626 drain_all_pages(zone);
1627
1628 pfn = scan_movable_pages(start_pfn, end_pfn);
1629 if (pfn) {
1630 ret = do_migrate_range(pfn, end_pfn);
1631 goto repeat;
1632 }
1633
1634
1635
1636
1637
1638 ret = dissolve_free_huge_pages(start_pfn, end_pfn);
1639 if (ret)
1640 goto failed_removal;
1641
1642 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
1643 if (offlined_pages < 0)
1644 goto repeat;
1645 pr_info("Offlined Pages %ld\n", offlined_pages);
1646
1647
1648 offline_isolated_pages(start_pfn, end_pfn);
1649
1650 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1651
1652 adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
1653 zone->present_pages -= offlined_pages;
1654
1655 pgdat_resize_lock(zone->zone_pgdat, &flags);
1656 zone->zone_pgdat->node_present_pages -= offlined_pages;
1657 pgdat_resize_unlock(zone->zone_pgdat, &flags);
1658
1659 init_per_zone_wmark_min();
1660
1661 if (!populated_zone(zone)) {
1662 zone_pcp_reset(zone);
1663 build_all_zonelists(NULL);
1664 } else
1665 zone_pcp_update(zone);
1666
1667 node_states_clear_node(node, &arg);
1668 if (arg.status_change_nid >= 0) {
1669 kswapd_stop(node);
1670 kcompactd_stop(node);
1671 }
1672
1673 vm_total_pages = nr_free_pagecache_pages();
1674 writeback_set_ratelimit();
1675
1676 memory_notify(MEM_OFFLINE, &arg);
1677 return 0;
1678
1679failed_removal:
1680 pr_debug("memory offlining [mem %#010llx-%#010llx] failed\n",
1681 (unsigned long long) start_pfn << PAGE_SHIFT,
1682 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
1683 memory_notify(MEM_CANCEL_OFFLINE, &arg);
1684
1685 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
1686 return ret;
1687}
1688
1689
1690int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
1691{
1692 return __offline_pages(start_pfn, start_pfn + nr_pages);
1693}
1694#endif
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
1709 void *arg, int (*func)(struct memory_block *, void *))
1710{
1711 struct memory_block *mem = NULL;
1712 struct mem_section *section;
1713 unsigned long pfn, section_nr;
1714 int ret;
1715
1716 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1717 section_nr = pfn_to_section_nr(pfn);
1718 if (!present_section_nr(section_nr))
1719 continue;
1720
1721 section = __nr_to_section(section_nr);
1722
1723 if (mem)
1724 if ((section_nr >= mem->start_section_nr) &&
1725 (section_nr <= mem->end_section_nr))
1726 continue;
1727
1728 mem = find_memory_block_hinted(section, mem);
1729 if (!mem)
1730 continue;
1731
1732 ret = func(mem, arg);
1733 if (ret) {
1734 kobject_put(&mem->dev.kobj);
1735 return ret;
1736 }
1737 }
1738
1739 if (mem)
1740 kobject_put(&mem->dev.kobj);
1741
1742 return 0;
1743}
1744
1745#ifdef CONFIG_MEMORY_HOTREMOVE
1746static int check_memblock_offlined_cb(struct memory_block *mem, void *arg)
1747{
1748 int ret = !is_memblock_offlined(mem);
1749
1750 if (unlikely(ret)) {
1751 phys_addr_t beginpa, endpa;
1752
1753 beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr));
1754 endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1;
1755 pr_warn("removing memory fails, because memory [%pa-%pa] is onlined\n",
1756 &beginpa, &endpa);
1757 }
1758
1759 return ret;
1760}
1761
1762static int check_cpu_on_node(pg_data_t *pgdat)
1763{
1764 int cpu;
1765
1766 for_each_present_cpu(cpu) {
1767 if (cpu_to_node(cpu) == pgdat->node_id)
1768
1769
1770
1771
1772 return -EBUSY;
1773 }
1774
1775 return 0;
1776}
1777
1778static void unmap_cpu_on_node(pg_data_t *pgdat)
1779{
1780#ifdef CONFIG_ACPI_NUMA
1781 int cpu;
1782
1783 for_each_possible_cpu(cpu)
1784 if (cpu_to_node(cpu) == pgdat->node_id)
1785 numa_clear_node(cpu);
1786#endif
1787}
1788
1789static int check_and_unmap_cpu_on_node(pg_data_t *pgdat)
1790{
1791 int ret;
1792
1793 ret = check_cpu_on_node(pgdat);
1794 if (ret)
1795 return ret;
1796
1797
1798
1799
1800
1801
1802 unmap_cpu_on_node(pgdat);
1803 return 0;
1804}
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815void try_offline_node(int nid)
1816{
1817 pg_data_t *pgdat = NODE_DATA(nid);
1818 unsigned long start_pfn = pgdat->node_start_pfn;
1819 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
1820 unsigned long pfn;
1821
1822 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1823 unsigned long section_nr = pfn_to_section_nr(pfn);
1824
1825 if (!present_section_nr(section_nr))
1826 continue;
1827
1828 if (pfn_to_nid(pfn) != nid)
1829 continue;
1830
1831
1832
1833
1834
1835 return;
1836 }
1837
1838 if (check_and_unmap_cpu_on_node(pgdat))
1839 return;
1840
1841
1842
1843
1844
1845 node_set_offline(nid);
1846 unregister_one_node(nid);
1847}
1848EXPORT_SYMBOL(try_offline_node);
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860void __ref remove_memory(int nid, u64 start, u64 size)
1861{
1862 int ret;
1863
1864 BUG_ON(check_hotplug_memory_range(start, size));
1865
1866 mem_hotplug_begin();
1867
1868
1869
1870
1871
1872
1873 ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
1874 check_memblock_offlined_cb);
1875 if (ret)
1876 BUG();
1877
1878
1879 firmware_map_remove(start, start + size, "System RAM");
1880 memblock_free(start, size);
1881 memblock_remove(start, size);
1882
1883 arch_remove_memory(start, size, NULL);
1884
1885 try_offline_node(nid);
1886
1887 mem_hotplug_done();
1888}
1889EXPORT_SYMBOL_GPL(remove_memory);
1890#endif
1891