blob: b81a367b9f39bb056cc4127a674e8a3dd4d2567d [file] [log] [blame]
Dave Hansen3947be12005-10-29 18:16:54 -07001/*
2 * linux/mm/memory_hotplug.c
3 *
4 * Copyright (C)
5 */
6
Dave Hansen3947be12005-10-29 18:16:54 -07007#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>
Paul Gortmakerb95f1b312011-10-16 02:01:52 -040014#include <linux/export.h>
Dave Hansen3947be12005-10-29 18:16:54 -070015#include <linux/pagevec.h>
Chandra Seetharaman2d1d43f2006-09-29 02:01:25 -070016#include <linux/writeback.h>
Dave Hansen3947be12005-10-29 18:16:54 -070017#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>
KAMEZAWA Hiroyuki0a547032006-06-27 02:53:35 -070024#include <linux/ioport.h>
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -070025#include <linux/delay.h>
26#include <linux/migrate.h>
27#include <linux/page-isolation.h>
Badari Pulavarty71088782008-10-18 20:25:58 -070028#include <linux/pfn.h>
Andi Kleen6ad696d2009-11-17 14:06:22 -080029#include <linux/suspend.h>
KOSAKI Motohiro6d9c2852009-12-14 17:58:11 -080030#include <linux/mm_inline.h>
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -080031#include <linux/firmware-map.h>
Tang Chen60a5a192013-02-22 16:33:14 -080032#include <linux/stop_machine.h>
Dave Hansen3947be12005-10-29 18:16:54 -070033
34#include <asm/tlbflush.h>
35
Adrian Bunk1e5ad9a2008-04-28 20:40:08 +030036#include "internal.h"
37
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -070038/*
39 * online_page_callback contains pointer to current page onlining function.
40 * Initially it is generic_online_page(). If it is required it could be
41 * changed by calling set_online_page_callback() for callback registration
42 * and restore_online_page_callback() for generic callback restore.
43 */
44
45static void generic_online_page(struct page *page);
46
47static online_page_callback_t online_page_callback = generic_online_page;
48
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -080049DEFINE_MUTEX(mem_hotplug_mutex);
50
51void lock_memory_hotplug(void)
52{
53 mutex_lock(&mem_hotplug_mutex);
54
55 /* for exclusive hibernation if CONFIG_HIBERNATION=y */
56 lock_system_sleep();
57}
58
59void unlock_memory_hotplug(void)
60{
61 unlock_system_sleep();
62 mutex_unlock(&mem_hotplug_mutex);
63}
64
65
Keith Mannthey45e0b782006-09-30 23:27:09 -070066/* add this memory to iomem resource */
67static struct resource *register_memory_resource(u64 start, u64 size)
68{
69 struct resource *res;
70 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
71 BUG_ON(!res);
72
73 res->name = "System RAM";
74 res->start = start;
75 res->end = start + size - 1;
Yasunori Goto887c3cb2007-11-14 16:59:20 -080076 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
Keith Mannthey45e0b782006-09-30 23:27:09 -070077 if (request_resource(&iomem_resource, res) < 0) {
Bjorn Helgaasa62e2f42012-05-29 15:06:30 -070078 printk("System RAM resource %pR cannot be added\n", res);
Keith Mannthey45e0b782006-09-30 23:27:09 -070079 kfree(res);
80 res = NULL;
81 }
82 return res;
83}
84
85static void release_memory_resource(struct resource *res)
86{
87 if (!res)
88 return;
89 release_resource(res);
90 kfree(res);
91 return;
92}
93
Keith Mannthey53947022006-09-30 23:27:08 -070094#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
Yasuaki Ishimatsu46723bf2013-02-22 16:33:00 -080095void get_page_bootmem(unsigned long info, struct page *page,
96 unsigned long type)
Yasunori Goto04753272008-04-28 02:13:31 -070097{
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -080098 page->lru.next = (struct list_head *) type;
Yasunori Goto04753272008-04-28 02:13:31 -070099 SetPagePrivate(page);
100 set_page_private(page, info);
101 atomic_inc(&page->_count);
102}
103
Rakib Mullick23ce9322009-12-14 17:59:44 -0800104/* reference to __meminit __free_pages_bootmem is valid
105 * so use __ref to tell modpost not to generate a warning */
106void __ref put_page_bootmem(struct page *page)
Yasunori Goto04753272008-04-28 02:13:31 -0700107{
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -0800108 unsigned long type;
Jiang Liu9feedc92012-12-12 13:52:12 -0800109 static DEFINE_MUTEX(ppb_lock);
Yasunori Goto04753272008-04-28 02:13:31 -0700110
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -0800111 type = (unsigned long) page->lru.next;
112 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
113 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
Yasunori Goto04753272008-04-28 02:13:31 -0700114
115 if (atomic_dec_return(&page->_count) == 1) {
116 ClearPagePrivate(page);
117 set_page_private(page, 0);
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -0800118 INIT_LIST_HEAD(&page->lru);
Jiang Liu9feedc92012-12-12 13:52:12 -0800119
120 /*
121 * Please refer to comment for __free_pages_bootmem()
122 * for why we serialize here.
123 */
124 mutex_lock(&ppb_lock);
Yasunori Goto04753272008-04-28 02:13:31 -0700125 __free_pages_bootmem(page, 0);
Jiang Liu9feedc92012-12-12 13:52:12 -0800126 mutex_unlock(&ppb_lock);
Jiang Liuc60514b2013-02-22 16:33:56 -0800127 totalram_pages++;
Yasunori Goto04753272008-04-28 02:13:31 -0700128 }
129
130}
131
Yasuaki Ishimatsu46723bf2013-02-22 16:33:00 -0800132#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
133#ifndef CONFIG_SPARSEMEM_VMEMMAP
Adrian Bunkd92bc312008-07-23 21:28:12 -0700134static void register_page_bootmem_info_section(unsigned long start_pfn)
Yasunori Goto04753272008-04-28 02:13:31 -0700135{
136 unsigned long *usemap, mapsize, section_nr, i;
137 struct mem_section *ms;
138 struct page *page, *memmap;
139
Yasunori Goto04753272008-04-28 02:13:31 -0700140 section_nr = pfn_to_section_nr(start_pfn);
141 ms = __nr_to_section(section_nr);
142
143 /* Get section's memmap address */
144 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
145
146 /*
147 * Get page for the memmap's phys address
148 * XXX: need more consideration for sparse_vmemmap...
149 */
150 page = virt_to_page(memmap);
151 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
152 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
153
154 /* remember memmap's page */
155 for (i = 0; i < mapsize; i++, page++)
156 get_page_bootmem(section_nr, page, SECTION_INFO);
157
158 usemap = __nr_to_section(section_nr)->pageblock_flags;
159 page = virt_to_page(usemap);
160
161 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
162
163 for (i = 0; i < mapsize; i++, page++)
Yasunori Gotoaf370fb2008-07-23 21:28:17 -0700164 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
Yasunori Goto04753272008-04-28 02:13:31 -0700165
166}
Yasuaki Ishimatsu46723bf2013-02-22 16:33:00 -0800167#else /* CONFIG_SPARSEMEM_VMEMMAP */
168static void register_page_bootmem_info_section(unsigned long start_pfn)
169{
170 unsigned long *usemap, mapsize, section_nr, i;
171 struct mem_section *ms;
172 struct page *page, *memmap;
173
174 if (!pfn_valid(start_pfn))
175 return;
176
177 section_nr = pfn_to_section_nr(start_pfn);
178 ms = __nr_to_section(section_nr);
179
180 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
181
182 register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
183
184 usemap = __nr_to_section(section_nr)->pageblock_flags;
185 page = virt_to_page(usemap);
186
187 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
188
189 for (i = 0; i < mapsize; i++, page++)
190 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
191}
192#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
Yasunori Goto04753272008-04-28 02:13:31 -0700193
194void register_page_bootmem_info_node(struct pglist_data *pgdat)
195{
196 unsigned long i, pfn, end_pfn, nr_pages;
197 int node = pgdat->node_id;
198 struct page *page;
199 struct zone *zone;
200
201 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
202 page = virt_to_page(pgdat);
203
204 for (i = 0; i < nr_pages; i++, page++)
205 get_page_bootmem(node, page, NODE_INFO);
206
207 zone = &pgdat->node_zones[0];
208 for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
209 if (zone->wait_table) {
210 nr_pages = zone->wait_table_hash_nr_entries
211 * sizeof(wait_queue_head_t);
212 nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
213 page = virt_to_page(zone->wait_table);
214
215 for (i = 0; i < nr_pages; i++, page++)
216 get_page_bootmem(node, page, NODE_INFO);
217 }
218 }
219
220 pfn = pgdat->node_start_pfn;
Cody P Schaferc1f19492013-02-22 16:35:32 -0800221 end_pfn = pgdat_end_pfn(pgdat);
Yasunori Goto04753272008-04-28 02:13:31 -0700222
223 /* register_section info */
qiuxishif14851a2012-09-17 14:09:24 -0700224 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
225 /*
226 * Some platforms can assign the same pfn to multiple nodes - on
227 * node0 as well as nodeN. To avoid registering a pfn against
228 * multiple nodes we check that this pfn does not already
229 * reside in some other node.
230 */
231 if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node))
232 register_page_bootmem_info_section(pfn);
233 }
Yasunori Goto04753272008-04-28 02:13:31 -0700234}
Yasuaki Ishimatsu46723bf2013-02-22 16:33:00 -0800235#endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
Yasunori Goto04753272008-04-28 02:13:31 -0700236
Heiko Carstens76cdd582008-05-14 16:05:52 -0700237static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
238 unsigned long end_pfn)
239{
240 unsigned long old_zone_end_pfn;
241
242 zone_span_writelock(zone);
243
244 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
Tang Chen712cd382012-12-11 16:01:07 -0800245 if (!zone->spanned_pages || start_pfn < zone->zone_start_pfn)
Heiko Carstens76cdd582008-05-14 16:05:52 -0700246 zone->zone_start_pfn = start_pfn;
247
248 zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
249 zone->zone_start_pfn;
250
251 zone_span_writeunlock(zone);
252}
253
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800254static void resize_zone(struct zone *zone, unsigned long start_pfn,
255 unsigned long end_pfn)
256{
257 zone_span_writelock(zone);
258
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800259 if (end_pfn - start_pfn) {
260 zone->zone_start_pfn = start_pfn;
261 zone->spanned_pages = end_pfn - start_pfn;
262 } else {
263 /*
264 * make it consist as free_area_init_core(),
265 * if spanned_pages = 0, then keep start_pfn = 0
266 */
267 zone->zone_start_pfn = 0;
268 zone->spanned_pages = 0;
269 }
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800270
271 zone_span_writeunlock(zone);
272}
273
274static void fix_zone_id(struct zone *zone, unsigned long start_pfn,
275 unsigned long end_pfn)
276{
277 enum zone_type zid = zone_idx(zone);
278 int nid = zone->zone_pgdat->node_id;
279 unsigned long pfn;
280
281 for (pfn = start_pfn; pfn < end_pfn; pfn++)
282 set_page_links(pfn_to_page(pfn), zid, nid, pfn);
283}
284
Cody P Schaferf6bbb782013-02-22 16:35:30 -0800285/* Can fail with -ENOMEM from allocating a wait table with vmalloc() or
286 * alloc_bootmem_node_nopanic() */
287static int __ref ensure_zone_is_initialized(struct zone *zone,
288 unsigned long start_pfn, unsigned long num_pages)
289{
290 if (!zone_is_initialized(zone))
291 return init_currently_empty_zone(zone, start_pfn, num_pages,
292 MEMMAP_HOTPLUG);
293 return 0;
294}
295
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800296static int __meminit move_pfn_range_left(struct zone *z1, struct zone *z2,
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800297 unsigned long start_pfn, unsigned long end_pfn)
298{
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800299 int ret;
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800300 unsigned long flags;
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800301 unsigned long z1_start_pfn;
302
Cody P Schafer64dd1b22013-02-22 16:35:31 -0800303 ret = ensure_zone_is_initialized(z1, start_pfn, end_pfn - start_pfn);
304 if (ret)
305 return ret;
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800306
307 pgdat_resize_lock(z1->zone_pgdat, &flags);
308
309 /* can't move pfns which are higher than @z2 */
Cody P Schafer108bcc92013-02-22 16:35:23 -0800310 if (end_pfn > zone_end_pfn(z2))
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800311 goto out_fail;
312 /* the move out part mast at the left most of @z2 */
313 if (start_pfn > z2->zone_start_pfn)
314 goto out_fail;
315 /* must included/overlap */
316 if (end_pfn <= z2->zone_start_pfn)
317 goto out_fail;
318
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800319 /* use start_pfn for z1's start_pfn if z1 is empty */
320 if (z1->spanned_pages)
321 z1_start_pfn = z1->zone_start_pfn;
322 else
323 z1_start_pfn = start_pfn;
324
325 resize_zone(z1, z1_start_pfn, end_pfn);
Cody P Schafer108bcc92013-02-22 16:35:23 -0800326 resize_zone(z2, end_pfn, zone_end_pfn(z2));
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800327
328 pgdat_resize_unlock(z1->zone_pgdat, &flags);
329
330 fix_zone_id(z1, start_pfn, end_pfn);
331
332 return 0;
333out_fail:
334 pgdat_resize_unlock(z1->zone_pgdat, &flags);
335 return -1;
336}
337
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800338static int __meminit move_pfn_range_right(struct zone *z1, struct zone *z2,
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800339 unsigned long start_pfn, unsigned long end_pfn)
340{
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800341 int ret;
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800342 unsigned long flags;
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800343 unsigned long z2_end_pfn;
344
Cody P Schafer64dd1b22013-02-22 16:35:31 -0800345 ret = ensure_zone_is_initialized(z2, start_pfn, end_pfn - start_pfn);
346 if (ret)
347 return ret;
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800348
349 pgdat_resize_lock(z1->zone_pgdat, &flags);
350
351 /* can't move pfns which are lower than @z1 */
352 if (z1->zone_start_pfn > start_pfn)
353 goto out_fail;
354 /* the move out part mast at the right most of @z1 */
Cody P Schafer108bcc92013-02-22 16:35:23 -0800355 if (zone_end_pfn(z1) > end_pfn)
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800356 goto out_fail;
357 /* must included/overlap */
Cody P Schafer108bcc92013-02-22 16:35:23 -0800358 if (start_pfn >= zone_end_pfn(z1))
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800359 goto out_fail;
360
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800361 /* use end_pfn for z2's end_pfn if z2 is empty */
362 if (z2->spanned_pages)
Cody P Schafer108bcc92013-02-22 16:35:23 -0800363 z2_end_pfn = zone_end_pfn(z2);
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800364 else
365 z2_end_pfn = end_pfn;
366
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800367 resize_zone(z1, z1->zone_start_pfn, start_pfn);
Lai Jiangshane455a9b2012-12-11 16:03:20 -0800368 resize_zone(z2, start_pfn, z2_end_pfn);
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800369
370 pgdat_resize_unlock(z1->zone_pgdat, &flags);
371
372 fix_zone_id(z2, start_pfn, end_pfn);
373
374 return 0;
375out_fail:
376 pgdat_resize_unlock(z1->zone_pgdat, &flags);
377 return -1;
378}
379
Heiko Carstens76cdd582008-05-14 16:05:52 -0700380static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
381 unsigned long end_pfn)
382{
383 unsigned long old_pgdat_end_pfn =
384 pgdat->node_start_pfn + pgdat->node_spanned_pages;
385
Tang Chen712cd382012-12-11 16:01:07 -0800386 if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
Heiko Carstens76cdd582008-05-14 16:05:52 -0700387 pgdat->node_start_pfn = start_pfn;
388
389 pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
390 pgdat->node_start_pfn;
391}
392
Al Viro31168482008-11-22 17:33:24 +0000393static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
Dave Hansen3947be12005-10-29 18:16:54 -0700394{
395 struct pglist_data *pgdat = zone->zone_pgdat;
396 int nr_pages = PAGES_PER_SECTION;
397 int nid = pgdat->node_id;
398 int zone_type;
Heiko Carstens76cdd582008-05-14 16:05:52 -0700399 unsigned long flags;
Cody P Schafer64dd1b22013-02-22 16:35:31 -0800400 int ret;
Dave Hansen3947be12005-10-29 18:16:54 -0700401
402 zone_type = zone - pgdat->node_zones;
Cody P Schafer64dd1b22013-02-22 16:35:31 -0800403 ret = ensure_zone_is_initialized(zone, phys_start_pfn, nr_pages);
404 if (ret)
405 return ret;
Heiko Carstens76cdd582008-05-14 16:05:52 -0700406
Heiko Carstens76cdd582008-05-14 16:05:52 -0700407 pgdat_resize_lock(zone->zone_pgdat, &flags);
408 grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
409 grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
410 phys_start_pfn + nr_pages);
411 pgdat_resize_unlock(zone->zone_pgdat, &flags);
Dave Hansena2f3aa022007-01-10 23:15:30 -0800412 memmap_init_zone(nr_pages, nid, zone_type,
413 phys_start_pfn, MEMMAP_HOTPLUG);
Yasunori Goto718127c2006-06-23 02:03:10 -0700414 return 0;
Dave Hansen3947be12005-10-29 18:16:54 -0700415}
416
Gary Hadec04fc582009-01-06 14:39:14 -0800417static int __meminit __add_section(int nid, struct zone *zone,
418 unsigned long phys_start_pfn)
Dave Hansen3947be12005-10-29 18:16:54 -0700419{
Dave Hansen3947be12005-10-29 18:16:54 -0700420 int nr_pages = PAGES_PER_SECTION;
Dave Hansen3947be12005-10-29 18:16:54 -0700421 int ret;
422
KAMEZAWA Hiroyukiebd15302006-08-05 12:15:06 -0700423 if (pfn_valid(phys_start_pfn))
424 return -EEXIST;
425
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700426 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
Dave Hansen3947be12005-10-29 18:16:54 -0700427
428 if (ret < 0)
429 return ret;
430
Yasunori Goto718127c2006-06-23 02:03:10 -0700431 ret = __add_zone(zone, phys_start_pfn);
432
433 if (ret < 0)
434 return ret;
435
Gary Hadec04fc582009-01-06 14:39:14 -0800436 return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
Dave Hansen3947be12005-10-29 18:16:54 -0700437}
438
Yasuaki Ishimatsu815121d2013-02-22 16:33:12 -0800439/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
440static int find_smallest_section_pfn(int nid, struct zone *zone,
441 unsigned long start_pfn,
442 unsigned long end_pfn)
443{
444 struct mem_section *ms;
445
446 for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
447 ms = __pfn_to_section(start_pfn);
448
449 if (unlikely(!valid_section(ms)))
450 continue;
451
452 if (unlikely(pfn_to_nid(start_pfn) != nid))
453 continue;
454
455 if (zone && zone != page_zone(pfn_to_page(start_pfn)))
456 continue;
457
458 return start_pfn;
459 }
460
461 return 0;
462}
463
464/* find the biggest valid pfn in the range [start_pfn, end_pfn). */
465static int find_biggest_section_pfn(int nid, struct zone *zone,
466 unsigned long start_pfn,
467 unsigned long end_pfn)
468{
469 struct mem_section *ms;
470 unsigned long pfn;
471
472 /* pfn is the end pfn of a memory section. */
473 pfn = end_pfn - 1;
474 for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
475 ms = __pfn_to_section(pfn);
476
477 if (unlikely(!valid_section(ms)))
478 continue;
479
480 if (unlikely(pfn_to_nid(pfn) != nid))
481 continue;
482
483 if (zone && zone != page_zone(pfn_to_page(pfn)))
484 continue;
485
486 return pfn;
487 }
488
489 return 0;
490}
491
492static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
493 unsigned long end_pfn)
494{
495 unsigned long zone_start_pfn = zone->zone_start_pfn;
496 unsigned long zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
497 unsigned long pfn;
498 struct mem_section *ms;
499 int nid = zone_to_nid(zone);
500
501 zone_span_writelock(zone);
502 if (zone_start_pfn == start_pfn) {
503 /*
504 * If the section is smallest section in the zone, it need
505 * shrink zone->zone_start_pfn and zone->zone_spanned_pages.
506 * In this case, we find second smallest valid mem_section
507 * for shrinking zone.
508 */
509 pfn = find_smallest_section_pfn(nid, zone, end_pfn,
510 zone_end_pfn);
511 if (pfn) {
512 zone->zone_start_pfn = pfn;
513 zone->spanned_pages = zone_end_pfn - pfn;
514 }
515 } else if (zone_end_pfn == end_pfn) {
516 /*
517 * If the section is biggest section in the zone, it need
518 * shrink zone->spanned_pages.
519 * In this case, we find second biggest valid mem_section for
520 * shrinking zone.
521 */
522 pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
523 start_pfn);
524 if (pfn)
525 zone->spanned_pages = pfn - zone_start_pfn + 1;
526 }
527
528 /*
529 * The section is not biggest or smallest mem_section in the zone, it
530 * only creates a hole in the zone. So in this case, we need not
531 * change the zone. But perhaps, the zone has only hole data. Thus
532 * it check the zone has only hole or not.
533 */
534 pfn = zone_start_pfn;
535 for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
536 ms = __pfn_to_section(pfn);
537
538 if (unlikely(!valid_section(ms)))
539 continue;
540
541 if (page_zone(pfn_to_page(pfn)) != zone)
542 continue;
543
544 /* If the section is current section, it continues the loop */
545 if (start_pfn == pfn)
546 continue;
547
548 /* If we find valid section, we have nothing to do */
549 zone_span_writeunlock(zone);
550 return;
551 }
552
553 /* The zone has no valid section */
554 zone->zone_start_pfn = 0;
555 zone->spanned_pages = 0;
556 zone_span_writeunlock(zone);
557}
558
559static void shrink_pgdat_span(struct pglist_data *pgdat,
560 unsigned long start_pfn, unsigned long end_pfn)
561{
562 unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
563 unsigned long pgdat_end_pfn =
564 pgdat->node_start_pfn + pgdat->node_spanned_pages;
565 unsigned long pfn;
566 struct mem_section *ms;
567 int nid = pgdat->node_id;
568
569 if (pgdat_start_pfn == start_pfn) {
570 /*
571 * If the section is smallest section in the pgdat, it need
572 * shrink pgdat->node_start_pfn and pgdat->node_spanned_pages.
573 * In this case, we find second smallest valid mem_section
574 * for shrinking zone.
575 */
576 pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
577 pgdat_end_pfn);
578 if (pfn) {
579 pgdat->node_start_pfn = pfn;
580 pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
581 }
582 } else if (pgdat_end_pfn == end_pfn) {
583 /*
584 * If the section is biggest section in the pgdat, it need
585 * shrink pgdat->node_spanned_pages.
586 * In this case, we find second biggest valid mem_section for
587 * shrinking zone.
588 */
589 pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
590 start_pfn);
591 if (pfn)
592 pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
593 }
594
595 /*
596 * If the section is not biggest or smallest mem_section in the pgdat,
597 * it only creates a hole in the pgdat. So in this case, we need not
598 * change the pgdat.
599 * But perhaps, the pgdat has only hole data. Thus it check the pgdat
600 * has only hole or not.
601 */
602 pfn = pgdat_start_pfn;
603 for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
604 ms = __pfn_to_section(pfn);
605
606 if (unlikely(!valid_section(ms)))
607 continue;
608
609 if (pfn_to_nid(pfn) != nid)
610 continue;
611
612 /* If the section is current section, it continues the loop */
613 if (start_pfn == pfn)
614 continue;
615
616 /* If we find valid section, we have nothing to do */
617 return;
618 }
619
620 /* The pgdat has no valid section */
621 pgdat->node_start_pfn = 0;
622 pgdat->node_spanned_pages = 0;
623}
624
625static void __remove_zone(struct zone *zone, unsigned long start_pfn)
626{
627 struct pglist_data *pgdat = zone->zone_pgdat;
628 int nr_pages = PAGES_PER_SECTION;
629 int zone_type;
630 unsigned long flags;
631
632 zone_type = zone - pgdat->node_zones;
633
634 pgdat_resize_lock(zone->zone_pgdat, &flags);
635 shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
636 shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
637 pgdat_resize_unlock(zone->zone_pgdat, &flags);
638}
639
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700640static int __remove_section(struct zone *zone, struct mem_section *ms)
641{
Yasuaki Ishimatsu815121d2013-02-22 16:33:12 -0800642 unsigned long start_pfn;
643 int scn_nr;
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700644 int ret = -EINVAL;
645
646 if (!valid_section(ms))
647 return ret;
648
649 ret = unregister_memory_section(ms);
650 if (ret)
651 return ret;
652
Yasuaki Ishimatsu815121d2013-02-22 16:33:12 -0800653 scn_nr = __section_nr(ms);
654 start_pfn = section_nr_to_pfn(scn_nr);
655 __remove_zone(zone, start_pfn);
656
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700657 sparse_remove_one_section(zone, ms);
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700658 return 0;
659}
660
Dave Hansen3947be12005-10-29 18:16:54 -0700661/*
662 * Reasonably generic function for adding memory. It is
663 * expected that archs that support memory hotplug will
664 * call this function after deciding the zone to which to
665 * add the new pages.
666 */
Gary Hadec04fc582009-01-06 14:39:14 -0800667int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
668 unsigned long nr_pages)
Dave Hansen3947be12005-10-29 18:16:54 -0700669{
670 unsigned long i;
671 int err = 0;
KAMEZAWA Hiroyuki6f712712006-08-05 12:14:58 -0700672 int start_sec, end_sec;
673 /* during initialize mem_map, align hot-added range to section */
674 start_sec = pfn_to_section_nr(phys_start_pfn);
675 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
Dave Hansen3947be12005-10-29 18:16:54 -0700676
KAMEZAWA Hiroyuki6f712712006-08-05 12:14:58 -0700677 for (i = start_sec; i <= end_sec; i++) {
Gary Hadec04fc582009-01-06 14:39:14 -0800678 err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
Dave Hansen3947be12005-10-29 18:16:54 -0700679
KAMEZAWA Hiroyuki6f712712006-08-05 12:14:58 -0700680 /*
Simon Arlott183ff222007-10-20 01:27:18 +0200681 * EEXIST is finally dealt with by ioresource collision
KAMEZAWA Hiroyuki6f712712006-08-05 12:14:58 -0700682 * check. see add_memory() => register_memory_resource()
683 * Warning will be printed if there is collision.
Joel H Schoppbed120c2006-05-01 12:16:11 -0700684 */
685 if (err && (err != -EEXIST))
Dave Hansen3947be12005-10-29 18:16:54 -0700686 break;
KAMEZAWA Hiroyuki6f712712006-08-05 12:14:58 -0700687 err = 0;
Dave Hansen3947be12005-10-29 18:16:54 -0700688 }
689
690 return err;
691}
Joel H Schoppbed120c2006-05-01 12:16:11 -0700692EXPORT_SYMBOL_GPL(__add_pages);
Dave Hansen3947be12005-10-29 18:16:54 -0700693
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700694/**
695 * __remove_pages() - remove sections of pages from a zone
696 * @zone: zone from which pages need to be removed
697 * @phys_start_pfn: starting pageframe (must be aligned to start of a section)
698 * @nr_pages: number of pages to remove (must be multiple of section size)
699 *
700 * Generic helper function to remove section mappings and sysfs entries
701 * for the section of the memory we are removing. Caller needs to make
702 * sure that pages are marked reserved and zones are adjust properly by
703 * calling offline_pages().
704 */
705int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
706 unsigned long nr_pages)
707{
708 unsigned long i, ret = 0;
709 int sections_to_remove;
710
711 /*
712 * We can only remove entire sections
713 */
714 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
715 BUG_ON(nr_pages % PAGES_PER_SECTION);
716
Yasuaki Ishimatsud760afd2012-10-08 16:34:14 -0700717 release_mem_region(phys_start_pfn << PAGE_SHIFT, nr_pages * PAGE_SIZE);
718
Badari Pulavartyea01ea92008-04-28 02:12:01 -0700719 sections_to_remove = nr_pages / PAGES_PER_SECTION;
720 for (i = 0; i < sections_to_remove; i++) {
721 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
722 ret = __remove_section(zone, __pfn_to_section(pfn));
723 if (ret)
724 break;
725 }
726 return ret;
727}
728EXPORT_SYMBOL_GPL(__remove_pages);
729
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700730int set_online_page_callback(online_page_callback_t callback)
731{
732 int rc = -EINVAL;
733
734 lock_memory_hotplug();
735
736 if (online_page_callback == generic_online_page) {
737 online_page_callback = callback;
738 rc = 0;
739 }
740
741 unlock_memory_hotplug();
742
743 return rc;
744}
745EXPORT_SYMBOL_GPL(set_online_page_callback);
746
747int restore_online_page_callback(online_page_callback_t callback)
748{
749 int rc = -EINVAL;
750
751 lock_memory_hotplug();
752
753 if (online_page_callback == callback) {
754 online_page_callback = generic_online_page;
755 rc = 0;
756 }
757
758 unlock_memory_hotplug();
759
760 return rc;
761}
762EXPORT_SYMBOL_GPL(restore_online_page_callback);
763
764void __online_page_set_limits(struct page *page)
Jeremy Fitzhardinge180c06e2008-04-28 02:12:03 -0700765{
Jan Beulich4738e1b2009-09-21 17:03:03 -0700766 unsigned long pfn = page_to_pfn(page);
767
Jan Beulich4738e1b2009-09-21 17:03:03 -0700768 if (pfn >= num_physpages)
769 num_physpages = pfn + 1;
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700770}
771EXPORT_SYMBOL_GPL(__online_page_set_limits);
772
773void __online_page_increment_counters(struct page *page)
774{
775 totalram_pages++;
Jeremy Fitzhardinge180c06e2008-04-28 02:12:03 -0700776
777#ifdef CONFIG_HIGHMEM
778 if (PageHighMem(page))
779 totalhigh_pages++;
780#endif
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700781}
782EXPORT_SYMBOL_GPL(__online_page_increment_counters);
Jeremy Fitzhardinge180c06e2008-04-28 02:12:03 -0700783
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700784void __online_page_free(struct page *page)
785{
Jeremy Fitzhardinge180c06e2008-04-28 02:12:03 -0700786 ClearPageReserved(page);
787 init_page_count(page);
788 __free_page(page);
789}
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700790EXPORT_SYMBOL_GPL(__online_page_free);
791
792static void generic_online_page(struct page *page)
793{
794 __online_page_set_limits(page);
795 __online_page_increment_counters(page);
796 __online_page_free(page);
797}
Jeremy Fitzhardinge180c06e2008-04-28 02:12:03 -0700798
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700799static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
800 void *arg)
Dave Hansen3947be12005-10-29 18:16:54 -0700801{
802 unsigned long i;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700803 unsigned long onlined_pages = *(unsigned long *)arg;
804 struct page *page;
805 if (PageReserved(pfn_to_page(start_pfn)))
806 for (i = 0; i < nr_pages; i++) {
807 page = pfn_to_page(start_pfn + i);
Daniel Kiper9d0ad8c2011-07-25 17:12:05 -0700808 (*online_page_callback)(page);
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700809 onlined_pages++;
810 }
811 *(unsigned long *)arg = onlined_pages;
812 return 0;
813}
814
Lai Jiangshan09285af2012-12-12 13:52:04 -0800815#ifdef CONFIG_MOVABLE_NODE
Tang Chen79a4dce2012-12-18 14:23:24 -0800816/*
817 * When CONFIG_MOVABLE_NODE, we permit onlining of a node which doesn't have
818 * normal memory.
819 */
Lai Jiangshan09285af2012-12-12 13:52:04 -0800820static bool can_online_high_movable(struct zone *zone)
821{
822 return true;
823}
Tang Chen79a4dce2012-12-18 14:23:24 -0800824#else /* CONFIG_MOVABLE_NODE */
Lai Jiangshan74d42d82012-12-11 16:03:23 -0800825/* ensure every online node has NORMAL memory */
826static bool can_online_high_movable(struct zone *zone)
827{
828 return node_state(zone_to_nid(zone), N_NORMAL_MEMORY);
829}
Tang Chen79a4dce2012-12-18 14:23:24 -0800830#endif /* CONFIG_MOVABLE_NODE */
Lai Jiangshan74d42d82012-12-11 16:03:23 -0800831
Lai Jiangshand9713672012-12-11 16:01:03 -0800832/* check which state of node_states will be changed when online memory */
833static void node_states_check_changes_online(unsigned long nr_pages,
834 struct zone *zone, struct memory_notify *arg)
835{
836 int nid = zone_to_nid(zone);
837 enum zone_type zone_last = ZONE_NORMAL;
838
839 /*
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800840 * If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
841 * contains nodes which have zones of 0...ZONE_NORMAL,
842 * set zone_last to ZONE_NORMAL.
Lai Jiangshand9713672012-12-11 16:01:03 -0800843 *
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800844 * If we don't have HIGHMEM nor movable node,
845 * node_states[N_NORMAL_MEMORY] contains nodes which have zones of
846 * 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
Lai Jiangshand9713672012-12-11 16:01:03 -0800847 */
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800848 if (N_MEMORY == N_NORMAL_MEMORY)
Lai Jiangshand9713672012-12-11 16:01:03 -0800849 zone_last = ZONE_MOVABLE;
850
851 /*
852 * if the memory to be online is in a zone of 0...zone_last, and
853 * the zones of 0...zone_last don't have memory before online, we will
854 * need to set the node to node_states[N_NORMAL_MEMORY] after
855 * the memory is online.
856 */
857 if (zone_idx(zone) <= zone_last && !node_state(nid, N_NORMAL_MEMORY))
858 arg->status_change_nid_normal = nid;
859 else
860 arg->status_change_nid_normal = -1;
861
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800862#ifdef CONFIG_HIGHMEM
863 /*
864 * If we have movable node, node_states[N_HIGH_MEMORY]
865 * contains nodes which have zones of 0...ZONE_HIGHMEM,
866 * set zone_last to ZONE_HIGHMEM.
867 *
868 * If we don't have movable node, node_states[N_NORMAL_MEMORY]
869 * contains nodes which have zones of 0...ZONE_MOVABLE,
870 * set zone_last to ZONE_MOVABLE.
871 */
872 zone_last = ZONE_HIGHMEM;
873 if (N_MEMORY == N_HIGH_MEMORY)
874 zone_last = ZONE_MOVABLE;
875
876 if (zone_idx(zone) <= zone_last && !node_state(nid, N_HIGH_MEMORY))
877 arg->status_change_nid_high = nid;
878 else
879 arg->status_change_nid_high = -1;
880#else
881 arg->status_change_nid_high = arg->status_change_nid_normal;
882#endif
883
Lai Jiangshand9713672012-12-11 16:01:03 -0800884 /*
885 * if the node don't have memory befor online, we will need to
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800886 * set the node to node_states[N_MEMORY] after the memory
Lai Jiangshand9713672012-12-11 16:01:03 -0800887 * is online.
888 */
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800889 if (!node_state(nid, N_MEMORY))
Lai Jiangshand9713672012-12-11 16:01:03 -0800890 arg->status_change_nid = nid;
891 else
892 arg->status_change_nid = -1;
893}
894
895static void node_states_set_node(int node, struct memory_notify *arg)
896{
897 if (arg->status_change_nid_normal >= 0)
898 node_set_state(node, N_NORMAL_MEMORY);
899
Lai Jiangshan6715ddf2012-12-12 13:51:49 -0800900 if (arg->status_change_nid_high >= 0)
901 node_set_state(node, N_HIGH_MEMORY);
902
903 node_set_state(node, N_MEMORY);
Lai Jiangshand9713672012-12-11 16:01:03 -0800904}
905
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700906
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800907int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700908{
Dave Hansen3947be12005-10-29 18:16:54 -0700909 unsigned long onlined_pages = 0;
910 struct zone *zone;
Yasunori Goto68113782006-06-23 02:03:11 -0700911 int need_zonelists_rebuild = 0;
Yasunori Goto7b78d332007-10-21 16:41:36 -0700912 int nid;
913 int ret;
914 struct memory_notify arg;
Dave Hansen3947be12005-10-29 18:16:54 -0700915
KAMEZAWA Hiroyuki925268a2011-01-11 16:44:01 +0900916 lock_memory_hotplug();
Lai Jiangshand9713672012-12-11 16:01:03 -0800917 /*
918 * This doesn't need a lock to do pfn_to_page().
919 * The section can't be removed here because of the
920 * memory_block->state_mutex.
921 */
922 zone = page_zone(pfn_to_page(pfn));
923
Lai Jiangshan74d42d82012-12-11 16:03:23 -0800924 if ((zone_idx(zone) > ZONE_NORMAL || online_type == ONLINE_MOVABLE) &&
925 !can_online_high_movable(zone)) {
926 unlock_memory_hotplug();
927 return -1;
928 }
929
Lai Jiangshan511c2ab2012-12-11 16:03:16 -0800930 if (online_type == ONLINE_KERNEL && zone_idx(zone) == ZONE_MOVABLE) {
931 if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages)) {
932 unlock_memory_hotplug();
933 return -1;
934 }
935 }
936 if (online_type == ONLINE_MOVABLE && zone_idx(zone) == ZONE_MOVABLE - 1) {
937 if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages)) {
938 unlock_memory_hotplug();
939 return -1;
940 }
941 }
942
943 /* Previous code may changed the zone of the pfn range */
944 zone = page_zone(pfn_to_page(pfn));
945
Yasunori Goto7b78d332007-10-21 16:41:36 -0700946 arg.start_pfn = pfn;
947 arg.nr_pages = nr_pages;
Lai Jiangshand9713672012-12-11 16:01:03 -0800948 node_states_check_changes_online(nr_pages, zone, &arg);
Yasunori Goto7b78d332007-10-21 16:41:36 -0700949
950 nid = page_to_nid(pfn_to_page(pfn));
Yasunori Goto7b78d332007-10-21 16:41:36 -0700951
952 ret = memory_notify(MEM_GOING_ONLINE, &arg);
953 ret = notifier_to_errno(ret);
954 if (ret) {
955 memory_notify(MEM_CANCEL_ONLINE, &arg);
KAMEZAWA Hiroyuki925268a2011-01-11 16:44:01 +0900956 unlock_memory_hotplug();
Yasunori Goto7b78d332007-10-21 16:41:36 -0700957 return ret;
958 }
Dave Hansen3947be12005-10-29 18:16:54 -0700959 /*
Yasunori Goto68113782006-06-23 02:03:11 -0700960 * If this zone is not populated, then it is not in zonelist.
961 * This means the page allocator ignores this zone.
962 * So, zonelist must be updated after online.
963 */
Haicheng Li4eaf3f62010-05-24 14:32:52 -0700964 mutex_lock(&zonelists_mutex);
Wen Congyang6dcd73d2012-12-11 16:01:01 -0800965 if (!populated_zone(zone)) {
Yasunori Goto68113782006-06-23 02:03:11 -0700966 need_zonelists_rebuild = 1;
Wen Congyang6dcd73d2012-12-11 16:01:01 -0800967 build_all_zonelists(NULL, zone);
968 }
Yasunori Goto68113782006-06-23 02:03:11 -0700969
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700970 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700971 online_pages_range);
Geoff Levandfd8a4222008-05-14 16:05:50 -0700972 if (ret) {
Wen Congyang6dcd73d2012-12-11 16:01:01 -0800973 if (need_zonelists_rebuild)
974 zone_pcp_reset(zone);
Haicheng Li4eaf3f62010-05-24 14:32:52 -0700975 mutex_unlock(&zonelists_mutex);
Bjorn Helgaasa62e2f42012-05-29 15:06:30 -0700976 printk(KERN_DEBUG "online_pages [mem %#010llx-%#010llx] failed\n",
977 (unsigned long long) pfn << PAGE_SHIFT,
978 (((unsigned long long) pfn + nr_pages)
979 << PAGE_SHIFT) - 1);
Geoff Levandfd8a4222008-05-14 16:05:50 -0700980 memory_notify(MEM_CANCEL_ONLINE, &arg);
KAMEZAWA Hiroyuki925268a2011-01-11 16:44:01 +0900981 unlock_memory_hotplug();
Geoff Levandfd8a4222008-05-14 16:05:50 -0700982 return ret;
983 }
984
Jiang Liu9feedc92012-12-12 13:52:12 -0800985 zone->managed_pages += onlined_pages;
Dave Hansen3947be12005-10-29 18:16:54 -0700986 zone->present_pages += onlined_pages;
Yasunori Gotof2937be2006-03-09 17:33:51 -0800987 zone->zone_pgdat->node_present_pages += onlined_pages;
Jiang Liu08dff7b2012-07-31 16:43:30 -0700988 if (onlined_pages) {
Lai Jiangshand9713672012-12-11 16:01:03 -0800989 node_states_set_node(zone_to_nid(zone), &arg);
Jiang Liu08dff7b2012-07-31 16:43:30 -0700990 if (need_zonelists_rebuild)
Wen Congyang6dcd73d2012-12-11 16:01:01 -0800991 build_all_zonelists(NULL, NULL);
Jiang Liu08dff7b2012-07-31 16:43:30 -0700992 else
993 zone_pcp_update(zone);
994 }
Dave Hansen3947be12005-10-29 18:16:54 -0700995
Haicheng Li4eaf3f62010-05-24 14:32:52 -0700996 mutex_unlock(&zonelists_mutex);
KOSAKI Motohiro1b79acc2011-05-24 17:11:32 -0700997
998 init_per_zone_wmark_min();
999
Jiang Liu08dff7b2012-07-31 16:43:30 -07001000 if (onlined_pages)
Christoph Lameter7ea15302007-10-16 01:25:29 -07001001 kswapd_run(zone_to_nid(zone));
Dave Hansen61b13992005-10-29 18:16:56 -07001002
Haicheng Li1f522502010-05-24 14:32:51 -07001003 vm_total_pages = nr_free_pagecache_pages();
Kent Liu2f7f24e2008-07-23 21:28:18 -07001004
Chandra Seetharaman2d1d43f2006-09-29 02:01:25 -07001005 writeback_set_ratelimit();
Yasunori Goto7b78d332007-10-21 16:41:36 -07001006
1007 if (onlined_pages)
1008 memory_notify(MEM_ONLINE, &arg);
KAMEZAWA Hiroyuki925268a2011-01-11 16:44:01 +09001009 unlock_memory_hotplug();
Yasunori Goto7b78d332007-10-21 16:41:36 -07001010
Dave Hansen3947be12005-10-29 18:16:54 -07001011 return 0;
1012}
Keith Mannthey53947022006-09-30 23:27:08 -07001013#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
Yasunori Gotobc02af92006-06-27 02:53:30 -07001014
Hidetoshi Setoe1319332009-11-17 14:06:18 -08001015/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
1016static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001017{
1018 struct pglist_data *pgdat;
1019 unsigned long zones_size[MAX_NR_ZONES] = {0};
1020 unsigned long zholes_size[MAX_NR_ZONES] = {0};
1021 unsigned long start_pfn = start >> PAGE_SHIFT;
1022
Tang Chena1e565a2013-02-22 16:33:18 -08001023 pgdat = NODE_DATA(nid);
1024 if (!pgdat) {
1025 pgdat = arch_alloc_nodedata(nid);
1026 if (!pgdat)
1027 return NULL;
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001028
Tang Chena1e565a2013-02-22 16:33:18 -08001029 arch_refresh_nodedata(nid, pgdat);
1030 }
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001031
1032 /* we can use NODE_DATA(nid) from here */
1033
1034 /* init node's zones as empty zones, we don't have any present pages.*/
Johannes Weiner9109fb72008-07-23 21:27:20 -07001035 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001036
KAMEZAWA Hiroyuki959ecc42011-06-15 15:08:38 -07001037 /*
1038 * The node we allocated has no zone fallback lists. For avoiding
1039 * to access not-initialized zonelist, build here.
1040 */
David Rientjesf957db42011-06-22 18:13:04 -07001041 mutex_lock(&zonelists_mutex);
Jiang Liu9adb62a2012-07-31 16:43:28 -07001042 build_all_zonelists(pgdat, NULL);
David Rientjesf957db42011-06-22 18:13:04 -07001043 mutex_unlock(&zonelists_mutex);
KAMEZAWA Hiroyuki959ecc42011-06-15 15:08:38 -07001044
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001045 return pgdat;
1046}
1047
1048static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
1049{
1050 arch_refresh_nodedata(nid, NULL);
1051 arch_free_nodedata(pgdat);
1052 return;
1053}
1054
KAMEZAWA Hiroyuki0a547032006-06-27 02:53:35 -07001055
minskey guocf234222010-05-24 14:32:41 -07001056/*
1057 * called by cpu_up() to online a node without onlined memory.
1058 */
1059int mem_online_node(int nid)
1060{
1061 pg_data_t *pgdat;
1062 int ret;
1063
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001064 lock_memory_hotplug();
minskey guocf234222010-05-24 14:32:41 -07001065 pgdat = hotadd_new_pgdat(nid, 0);
David Rientjes7553e8f2011-06-22 18:13:01 -07001066 if (!pgdat) {
minskey guocf234222010-05-24 14:32:41 -07001067 ret = -ENOMEM;
1068 goto out;
1069 }
1070 node_set_online(nid);
1071 ret = register_one_node(nid);
1072 BUG_ON(ret);
1073
1074out:
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001075 unlock_memory_hotplug();
minskey guocf234222010-05-24 14:32:41 -07001076 return ret;
1077}
1078
Al Viro31168482008-11-22 17:33:24 +00001079/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
1080int __ref add_memory(int nid, u64 start, u64 size)
Yasunori Gotobc02af92006-06-27 02:53:30 -07001081{
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001082 pg_data_t *pgdat = NULL;
Tang Chena1e565a2013-02-22 16:33:18 -08001083 bool new_pgdat;
1084 bool new_node;
KAMEZAWA Hiroyukiebd15302006-08-05 12:15:06 -07001085 struct resource *res;
Yasunori Gotobc02af92006-06-27 02:53:30 -07001086 int ret;
1087
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001088 lock_memory_hotplug();
Andi Kleen6ad696d2009-11-17 14:06:22 -08001089
KAMEZAWA Hiroyukiebd15302006-08-05 12:15:06 -07001090 res = register_memory_resource(start, size);
Andi Kleen6ad696d2009-11-17 14:06:22 -08001091 ret = -EEXIST;
KAMEZAWA Hiroyukiebd15302006-08-05 12:15:06 -07001092 if (!res)
Andi Kleen6ad696d2009-11-17 14:06:22 -08001093 goto out;
KAMEZAWA Hiroyukiebd15302006-08-05 12:15:06 -07001094
Tang Chena1e565a2013-02-22 16:33:18 -08001095 { /* Stupid hack to suppress address-never-null warning */
1096 void *p = NODE_DATA(nid);
1097 new_pgdat = !p;
1098 }
1099 new_node = !node_online(nid);
1100 if (new_node) {
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001101 pgdat = hotadd_new_pgdat(nid, start);
Andi Kleen6ad696d2009-11-17 14:06:22 -08001102 ret = -ENOMEM;
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001103 if (!pgdat)
Wen Congyang41b9e2d2012-07-11 14:02:31 -07001104 goto error;
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001105 }
1106
Yasunori Gotobc02af92006-06-27 02:53:30 -07001107 /* call arch's memory hotadd */
1108 ret = arch_add_memory(nid, start, size);
1109
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001110 if (ret < 0)
1111 goto error;
1112
Yasunori Goto0fc44152006-06-27 02:53:38 -07001113 /* we online node here. we can't roll back from here. */
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001114 node_set_online(nid);
1115
Tang Chena1e565a2013-02-22 16:33:18 -08001116 if (new_node) {
Yasunori Goto0fc44152006-06-27 02:53:38 -07001117 ret = register_one_node(nid);
1118 /*
1119 * If sysfs file of new node can't create, cpu on the node
1120 * can't be hot-added. There is no rollback way now.
1121 * So, check by BUG_ON() to catch it reluctantly..
1122 */
1123 BUG_ON(ret);
1124 }
1125
akpm@linux-foundation.orgd96ae532010-03-05 13:41:58 -08001126 /* create new memmap entry */
1127 firmware_map_add_hotplug(start, start + size, "System RAM");
1128
Andi Kleen6ad696d2009-11-17 14:06:22 -08001129 goto out;
1130
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001131error:
1132 /* rollback pgdat allocation and others */
1133 if (new_pgdat)
1134 rollback_node_hotadd(nid, pgdat);
Sasha Levina864b9d2013-02-22 16:32:48 -08001135 release_memory_resource(res);
Yasunori Goto9af3c2d2006-06-27 02:53:34 -07001136
Andi Kleen6ad696d2009-11-17 14:06:22 -08001137out:
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001138 unlock_memory_hotplug();
Yasunori Gotobc02af92006-06-27 02:53:30 -07001139 return ret;
1140}
1141EXPORT_SYMBOL_GPL(add_memory);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001142
1143#ifdef CONFIG_MEMORY_HOTREMOVE
1144/*
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001145 * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
1146 * set and the size of the free page is given by page_order(). Using this,
1147 * the function determines if the pageblock contains only free pages.
1148 * Due to buddy contraints, a free page at least the size of a pageblock will
1149 * be located at the start of the pageblock
1150 */
1151static inline int pageblock_free(struct page *page)
1152{
1153 return PageBuddy(page) && page_order(page) >= pageblock_order;
1154}
1155
1156/* Return the start of the next active pageblock after a given page */
1157static struct page *next_active_pageblock(struct page *page)
1158{
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001159 /* Ensure the starting page is pageblock-aligned */
1160 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
1161
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001162 /* If the entire pageblock is free, move to the end of free page */
KAMEZAWA Hiroyuki0dcc48c2010-09-09 16:38:01 -07001163 if (pageblock_free(page)) {
1164 int order;
1165 /* be careful. we don't have locks, page_order can be changed.*/
1166 order = page_order(page);
1167 if ((order < MAX_ORDER) && (order >= pageblock_order))
1168 return page + (1 << order);
1169 }
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001170
KAMEZAWA Hiroyuki0dcc48c2010-09-09 16:38:01 -07001171 return page + pageblock_nr_pages;
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001172}
1173
1174/* Checks if this range of memory is likely to be hot-removable. */
1175int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
1176{
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001177 struct page *page = pfn_to_page(start_pfn);
1178 struct page *end_page = page + nr_pages;
1179
1180 /* Check the starting page of each pageblock within the range */
1181 for (; page < end_page; page = next_active_pageblock(page)) {
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07001182 if (!is_pageblock_removable_nolock(page))
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001183 return 0;
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07001184 cond_resched();
Badari Pulavarty5c755e92008-07-23 21:28:19 -07001185 }
1186
1187 /* All pageblocks in the memory block are likely to be hot-removable */
1188 return 1;
1189}
1190
1191/*
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001192 * Confirm all pages in a range [start, end) is belongs to the same zone.
1193 */
1194static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
1195{
1196 unsigned long pfn;
1197 struct zone *zone = NULL;
1198 struct page *page;
1199 int i;
1200 for (pfn = start_pfn;
1201 pfn < end_pfn;
1202 pfn += MAX_ORDER_NR_PAGES) {
1203 i = 0;
1204 /* This is just a CONFIG_HOLES_IN_ZONE check.*/
1205 while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i))
1206 i++;
1207 if (i == MAX_ORDER_NR_PAGES)
1208 continue;
1209 page = pfn_to_page(pfn + i);
1210 if (zone && page_zone(page) != zone)
1211 return 0;
1212 zone = page_zone(page);
1213 }
1214 return 1;
1215}
1216
1217/*
1218 * Scanning pfn is much easier than scanning lru list.
1219 * Scan pfn from start to end and Find LRU page.
1220 */
Andrew Morton7bbc0902010-10-26 14:22:05 -07001221static unsigned long scan_lru_pages(unsigned long start, unsigned long end)
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001222{
1223 unsigned long pfn;
1224 struct page *page;
1225 for (pfn = start; pfn < end; pfn++) {
1226 if (pfn_valid(pfn)) {
1227 page = pfn_to_page(pfn);
1228 if (PageLRU(page))
1229 return pfn;
1230 }
1231 }
1232 return 0;
1233}
1234
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001235#define NR_OFFLINE_AT_ONCE_PAGES (256)
1236static int
1237do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
1238{
1239 unsigned long pfn;
1240 struct page *page;
1241 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
1242 int not_managed = 0;
1243 int ret = 0;
1244 LIST_HEAD(source);
1245
1246 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
1247 if (!pfn_valid(pfn))
1248 continue;
1249 page = pfn_to_page(pfn);
Konstantin Khlebnikov700c2a42011-05-24 17:12:19 -07001250 if (!get_page_unless_zero(page))
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001251 continue;
1252 /*
1253 * We can skip free pages. And we can only deal with pages on
1254 * LRU.
1255 */
Nick Piggin62695a82008-10-18 20:26:09 -07001256 ret = isolate_lru_page(page);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001257 if (!ret) { /* Success */
Konstantin Khlebnikov700c2a42011-05-24 17:12:19 -07001258 put_page(page);
Nick Piggin62695a82008-10-18 20:26:09 -07001259 list_add_tail(&page->lru, &source);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001260 move_pages--;
KOSAKI Motohiro6d9c2852009-12-14 17:58:11 -08001261 inc_zone_page_state(page, NR_ISOLATED_ANON +
1262 page_is_file_cache(page));
1263
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001264 } else {
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001265#ifdef CONFIG_DEBUG_VM
Wu Fengguang718a3822010-03-10 15:20:43 -08001266 printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
1267 pfn);
1268 dump_page(page);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001269#endif
Konstantin Khlebnikov700c2a42011-05-24 17:12:19 -07001270 put_page(page);
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001271 /* Because we don't have big zone->lock. we should
Bob Liu809c4442010-10-26 14:22:10 -07001272 check this again here. */
1273 if (page_count(page)) {
1274 not_managed++;
Bob Liuf3ab2632010-10-26 14:22:10 -07001275 ret = -EBUSY;
Bob Liu809c4442010-10-26 14:22:10 -07001276 break;
1277 }
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001278 }
1279 }
Bob Liuf3ab2632010-10-26 14:22:10 -07001280 if (!list_empty(&source)) {
1281 if (not_managed) {
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001282 putback_lru_pages(&source);
Bob Liuf3ab2632010-10-26 14:22:10 -07001283 goto out;
1284 }
Minchan Kim74c08f92012-10-08 16:32:54 -07001285
1286 /*
1287 * alloc_migrate_target should be improooooved!!
1288 * migrate_pages returns # of failed pages.
1289 */
1290 ret = migrate_pages(&source, alloc_migrate_target, 0,
Hugh Dickins9c620e22013-02-22 16:35:14 -08001291 MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
Bob Liuf3ab2632010-10-26 14:22:10 -07001292 if (ret)
1293 putback_lru_pages(&source);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001294 }
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001295out:
1296 return ret;
1297}
1298
1299/*
1300 * remove from free_area[] and mark all as Reserved.
1301 */
1302static int
1303offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
1304 void *data)
1305{
1306 __offline_isolated_pages(start, start + nr_pages);
1307 return 0;
1308}
1309
1310static void
1311offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
1312{
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -07001313 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001314 offline_isolated_pages_cb);
1315}
1316
1317/*
1318 * Check all pages in range, recoreded as memory resource, are isolated.
1319 */
1320static int
1321check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
1322 void *data)
1323{
1324 int ret;
1325 long offlined = *(long *)data;
Wen Congyangb023f462012-12-11 16:00:45 -08001326 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001327 offlined = nr_pages;
1328 if (!ret)
1329 *(long *)data += offlined;
1330 return ret;
1331}
1332
1333static long
1334check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
1335{
1336 long offlined = 0;
1337 int ret;
1338
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -07001339 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001340 check_pages_isolated_cb);
1341 if (ret < 0)
1342 offlined = (long)ret;
1343 return offlined;
1344}
1345
Lai Jiangshan09285af2012-12-12 13:52:04 -08001346#ifdef CONFIG_MOVABLE_NODE
Tang Chen79a4dce2012-12-18 14:23:24 -08001347/*
1348 * When CONFIG_MOVABLE_NODE, we permit offlining of a node which doesn't have
1349 * normal memory.
1350 */
Lai Jiangshan09285af2012-12-12 13:52:04 -08001351static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1352{
1353 return true;
1354}
Tang Chen79a4dce2012-12-18 14:23:24 -08001355#else /* CONFIG_MOVABLE_NODE */
Lai Jiangshan74d42d82012-12-11 16:03:23 -08001356/* ensure the node has NORMAL memory if it is still online */
1357static bool can_offline_normal(struct zone *zone, unsigned long nr_pages)
1358{
1359 struct pglist_data *pgdat = zone->zone_pgdat;
1360 unsigned long present_pages = 0;
1361 enum zone_type zt;
1362
1363 for (zt = 0; zt <= ZONE_NORMAL; zt++)
1364 present_pages += pgdat->node_zones[zt].present_pages;
1365
1366 if (present_pages > nr_pages)
1367 return true;
1368
1369 present_pages = 0;
1370 for (; zt <= ZONE_MOVABLE; zt++)
1371 present_pages += pgdat->node_zones[zt].present_pages;
1372
1373 /*
1374 * we can't offline the last normal memory until all
1375 * higher memory is offlined.
1376 */
1377 return present_pages == 0;
1378}
Tang Chen79a4dce2012-12-18 14:23:24 -08001379#endif /* CONFIG_MOVABLE_NODE */
Lai Jiangshan74d42d82012-12-11 16:03:23 -08001380
Lai Jiangshand9713672012-12-11 16:01:03 -08001381/* check which state of node_states will be changed when offline memory */
1382static void node_states_check_changes_offline(unsigned long nr_pages,
1383 struct zone *zone, struct memory_notify *arg)
1384{
1385 struct pglist_data *pgdat = zone->zone_pgdat;
1386 unsigned long present_pages = 0;
1387 enum zone_type zt, zone_last = ZONE_NORMAL;
1388
1389 /*
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001390 * If we have HIGHMEM or movable node, node_states[N_NORMAL_MEMORY]
1391 * contains nodes which have zones of 0...ZONE_NORMAL,
1392 * set zone_last to ZONE_NORMAL.
Lai Jiangshand9713672012-12-11 16:01:03 -08001393 *
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001394 * If we don't have HIGHMEM nor movable node,
1395 * node_states[N_NORMAL_MEMORY] contains nodes which have zones of
1396 * 0...ZONE_MOVABLE, set zone_last to ZONE_MOVABLE.
Lai Jiangshand9713672012-12-11 16:01:03 -08001397 */
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001398 if (N_MEMORY == N_NORMAL_MEMORY)
Lai Jiangshand9713672012-12-11 16:01:03 -08001399 zone_last = ZONE_MOVABLE;
1400
1401 /*
1402 * check whether node_states[N_NORMAL_MEMORY] will be changed.
1403 * If the memory to be offline is in a zone of 0...zone_last,
1404 * and it is the last present memory, 0...zone_last will
1405 * become empty after offline , thus we can determind we will
1406 * need to clear the node from node_states[N_NORMAL_MEMORY].
1407 */
1408 for (zt = 0; zt <= zone_last; zt++)
1409 present_pages += pgdat->node_zones[zt].present_pages;
1410 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1411 arg->status_change_nid_normal = zone_to_nid(zone);
1412 else
1413 arg->status_change_nid_normal = -1;
1414
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001415#ifdef CONFIG_HIGHMEM
1416 /*
1417 * If we have movable node, node_states[N_HIGH_MEMORY]
1418 * contains nodes which have zones of 0...ZONE_HIGHMEM,
1419 * set zone_last to ZONE_HIGHMEM.
1420 *
1421 * If we don't have movable node, node_states[N_NORMAL_MEMORY]
1422 * contains nodes which have zones of 0...ZONE_MOVABLE,
1423 * set zone_last to ZONE_MOVABLE.
1424 */
1425 zone_last = ZONE_HIGHMEM;
1426 if (N_MEMORY == N_HIGH_MEMORY)
1427 zone_last = ZONE_MOVABLE;
1428
1429 for (; zt <= zone_last; zt++)
1430 present_pages += pgdat->node_zones[zt].present_pages;
1431 if (zone_idx(zone) <= zone_last && nr_pages >= present_pages)
1432 arg->status_change_nid_high = zone_to_nid(zone);
1433 else
1434 arg->status_change_nid_high = -1;
1435#else
1436 arg->status_change_nid_high = arg->status_change_nid_normal;
1437#endif
1438
Lai Jiangshand9713672012-12-11 16:01:03 -08001439 /*
1440 * node_states[N_HIGH_MEMORY] contains nodes which have 0...ZONE_MOVABLE
1441 */
1442 zone_last = ZONE_MOVABLE;
1443
1444 /*
1445 * check whether node_states[N_HIGH_MEMORY] will be changed
1446 * If we try to offline the last present @nr_pages from the node,
1447 * we can determind we will need to clear the node from
1448 * node_states[N_HIGH_MEMORY].
1449 */
1450 for (; zt <= zone_last; zt++)
1451 present_pages += pgdat->node_zones[zt].present_pages;
1452 if (nr_pages >= present_pages)
1453 arg->status_change_nid = zone_to_nid(zone);
1454 else
1455 arg->status_change_nid = -1;
1456}
1457
1458static void node_states_clear_node(int node, struct memory_notify *arg)
1459{
1460 if (arg->status_change_nid_normal >= 0)
1461 node_clear_state(node, N_NORMAL_MEMORY);
1462
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001463 if ((N_MEMORY != N_NORMAL_MEMORY) &&
1464 (arg->status_change_nid_high >= 0))
Lai Jiangshand9713672012-12-11 16:01:03 -08001465 node_clear_state(node, N_HIGH_MEMORY);
Lai Jiangshan6715ddf2012-12-12 13:51:49 -08001466
1467 if ((N_MEMORY != N_HIGH_MEMORY) &&
1468 (arg->status_change_nid >= 0))
1469 node_clear_state(node, N_MEMORY);
Lai Jiangshand9713672012-12-11 16:01:03 -08001470}
1471
Wen Congyanga16cee12012-10-08 16:33:58 -07001472static int __ref __offline_pages(unsigned long start_pfn,
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001473 unsigned long end_pfn, unsigned long timeout)
1474{
1475 unsigned long pfn, nr_pages, expire;
1476 long offlined_pages;
Yasunori Goto7b78d332007-10-21 16:41:36 -07001477 int ret, drain, retry_max, node;
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001478 struct zone *zone;
Yasunori Goto7b78d332007-10-21 16:41:36 -07001479 struct memory_notify arg;
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001480
1481 BUG_ON(start_pfn >= end_pfn);
1482 /* at least, alignment against pageblock is necessary */
1483 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
1484 return -EINVAL;
1485 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
1486 return -EINVAL;
1487 /* This makes hotplug much easier...and readable.
1488 we assume this for now. .*/
1489 if (!test_pages_in_a_zone(start_pfn, end_pfn))
1490 return -EINVAL;
Yasunori Goto7b78d332007-10-21 16:41:36 -07001491
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001492 lock_memory_hotplug();
Andi Kleen6ad696d2009-11-17 14:06:22 -08001493
Yasunori Goto7b78d332007-10-21 16:41:36 -07001494 zone = page_zone(pfn_to_page(start_pfn));
1495 node = zone_to_nid(zone);
1496 nr_pages = end_pfn - start_pfn;
1497
Lai Jiangshan74d42d82012-12-11 16:03:23 -08001498 ret = -EINVAL;
1499 if (zone_idx(zone) <= ZONE_NORMAL && !can_offline_normal(zone, nr_pages))
1500 goto out;
1501
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001502 /* set above range as isolated */
Wen Congyangb023f462012-12-11 16:00:45 -08001503 ret = start_isolate_page_range(start_pfn, end_pfn,
1504 MIGRATE_MOVABLE, true);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001505 if (ret)
Andi Kleen6ad696d2009-11-17 14:06:22 -08001506 goto out;
Yasunori Goto7b78d332007-10-21 16:41:36 -07001507
1508 arg.start_pfn = start_pfn;
1509 arg.nr_pages = nr_pages;
Lai Jiangshand9713672012-12-11 16:01:03 -08001510 node_states_check_changes_offline(nr_pages, zone, &arg);
Yasunori Goto7b78d332007-10-21 16:41:36 -07001511
1512 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
1513 ret = notifier_to_errno(ret);
1514 if (ret)
1515 goto failed_removal;
1516
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001517 pfn = start_pfn;
1518 expire = jiffies + timeout;
1519 drain = 0;
1520 retry_max = 5;
1521repeat:
1522 /* start memory hot removal */
1523 ret = -EAGAIN;
1524 if (time_after(jiffies, expire))
1525 goto failed_removal;
1526 ret = -EINTR;
1527 if (signal_pending(current))
1528 goto failed_removal;
1529 ret = 0;
1530 if (drain) {
1531 lru_add_drain_all();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001532 cond_resched();
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001533 drain_all_pages();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001534 }
1535
1536 pfn = scan_lru_pages(start_pfn, end_pfn);
1537 if (pfn) { /* We have page on LRU */
1538 ret = do_migrate_range(pfn, end_pfn);
1539 if (!ret) {
1540 drain = 1;
1541 goto repeat;
1542 } else {
1543 if (ret < 0)
1544 if (--retry_max == 0)
1545 goto failed_removal;
1546 yield();
1547 drain = 1;
1548 goto repeat;
1549 }
1550 }
Adam Buchbinderb3834be2012-09-19 21:48:02 -04001551 /* drain all zone's lru pagevec, this is asynchronous... */
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001552 lru_add_drain_all();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001553 yield();
Adam Buchbinderb3834be2012-09-19 21:48:02 -04001554 /* drain pcp pages, this is synchronous. */
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001555 drain_all_pages();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001556 /* check again */
1557 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
1558 if (offlined_pages < 0) {
1559 ret = -EBUSY;
1560 goto failed_removal;
1561 }
1562 printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
Adam Buchbinderb3834be2012-09-19 21:48:02 -04001563 /* Ok, all of our target is isolated.
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001564 We cannot do rollback at this point. */
1565 offline_isolated_pages(start_pfn, end_pfn);
KAMEZAWA Hiroyukidbc0e4c2007-11-14 16:59:12 -08001566 /* reset pagetype flags and makes migrate type to be MOVABLE */
Michal Nazarewicz0815f3d2012-04-03 15:06:15 +02001567 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001568 /* removal success */
Jiang Liu9feedc92012-12-12 13:52:12 -08001569 zone->managed_pages -= offlined_pages;
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001570 zone->present_pages -= offlined_pages;
1571 zone->zone_pgdat->node_present_pages -= offlined_pages;
1572 totalram_pages -= offlined_pages;
Yasunori Goto7b78d332007-10-21 16:41:36 -07001573
KOSAKI Motohiro1b79acc2011-05-24 17:11:32 -07001574 init_per_zone_wmark_min();
1575
Xishi Qiu1e8537b2012-10-08 16:31:51 -07001576 if (!populated_zone(zone)) {
Jiang Liu340175b2012-07-31 16:43:32 -07001577 zone_pcp_reset(zone);
Xishi Qiu1e8537b2012-10-08 16:31:51 -07001578 mutex_lock(&zonelists_mutex);
1579 build_all_zonelists(NULL, NULL);
1580 mutex_unlock(&zonelists_mutex);
1581 } else
1582 zone_pcp_update(zone);
Jiang Liu340175b2012-07-31 16:43:32 -07001583
Lai Jiangshand9713672012-12-11 16:01:03 -08001584 node_states_clear_node(node, &arg);
1585 if (arg.status_change_nid >= 0)
David Rientjes8fe23e02009-12-14 17:58:33 -08001586 kswapd_stop(node);
Minchan Kimbce73942009-06-16 15:32:50 -07001587
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001588 vm_total_pages = nr_free_pagecache_pages();
1589 writeback_set_ratelimit();
Yasunori Goto7b78d332007-10-21 16:41:36 -07001590
1591 memory_notify(MEM_OFFLINE, &arg);
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001592 unlock_memory_hotplug();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001593 return 0;
1594
1595failed_removal:
Bjorn Helgaasa62e2f42012-05-29 15:06:30 -07001596 printk(KERN_INFO "memory offlining [mem %#010llx-%#010llx] failed\n",
1597 (unsigned long long) start_pfn << PAGE_SHIFT,
1598 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
Yasunori Goto7b78d332007-10-21 16:41:36 -07001599 memory_notify(MEM_CANCEL_OFFLINE, &arg);
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001600 /* pushback to free area */
Michal Nazarewicz0815f3d2012-04-03 15:06:15 +02001601 undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
Yasunori Goto7b78d332007-10-21 16:41:36 -07001602
Andi Kleen6ad696d2009-11-17 14:06:22 -08001603out:
KOSAKI Motohiro20d6c962010-12-02 14:31:19 -08001604 unlock_memory_hotplug();
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001605 return ret;
1606}
Badari Pulavarty71088782008-10-18 20:25:58 -07001607
Wen Congyanga16cee12012-10-08 16:33:58 -07001608int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
1609{
1610 return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
1611}
1612
Wen Congyangbbc76be2013-02-22 16:32:54 -08001613/**
1614 * walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
1615 * @start_pfn: start pfn of the memory range
1616 * @end_pfn: end pft of the memory range
1617 * @arg: argument passed to func
1618 * @func: callback for each memory section walked
1619 *
1620 * This function walks through all present mem sections in range
1621 * [start_pfn, end_pfn) and call func on each mem section.
1622 *
1623 * Returns the return value of func.
1624 */
1625static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
1626 void *arg, int (*func)(struct memory_block *, void *))
Badari Pulavarty71088782008-10-18 20:25:58 -07001627{
Wen Congyange90bdb72012-10-08 16:34:01 -07001628 struct memory_block *mem = NULL;
1629 struct mem_section *section;
Wen Congyange90bdb72012-10-08 16:34:01 -07001630 unsigned long pfn, section_nr;
1631 int ret;
Badari Pulavarty71088782008-10-18 20:25:58 -07001632
Wen Congyange90bdb72012-10-08 16:34:01 -07001633 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1634 section_nr = pfn_to_section_nr(pfn);
1635 if (!present_section_nr(section_nr))
1636 continue;
1637
1638 section = __nr_to_section(section_nr);
1639 /* same memblock? */
1640 if (mem)
1641 if ((section_nr >= mem->start_section_nr) &&
1642 (section_nr <= mem->end_section_nr))
1643 continue;
1644
1645 mem = find_memory_block_hinted(section, mem);
1646 if (!mem)
1647 continue;
1648
Wen Congyangbbc76be2013-02-22 16:32:54 -08001649 ret = func(mem, arg);
Wen Congyange90bdb72012-10-08 16:34:01 -07001650 if (ret) {
Wen Congyangbbc76be2013-02-22 16:32:54 -08001651 kobject_put(&mem->dev.kobj);
1652 return ret;
Wen Congyange90bdb72012-10-08 16:34:01 -07001653 }
1654 }
1655
1656 if (mem)
1657 kobject_put(&mem->dev.kobj);
1658
Wen Congyangbbc76be2013-02-22 16:32:54 -08001659 return 0;
1660}
1661
1662/**
1663 * offline_memory_block_cb - callback function for offlining memory block
1664 * @mem: the memory block to be offlined
1665 * @arg: buffer to hold error msg
1666 *
1667 * Always return 0, and put the error msg in arg if any.
1668 */
1669static int offline_memory_block_cb(struct memory_block *mem, void *arg)
1670{
1671 int *ret = arg;
1672 int error = offline_memory_block(mem);
1673
1674 if (error != 0 && *ret == 0)
1675 *ret = error;
1676
1677 return 0;
1678}
1679
1680static int is_memblock_offlined_cb(struct memory_block *mem, void *arg)
1681{
1682 int ret = !is_memblock_offlined(mem);
1683
1684 if (unlikely(ret))
1685 pr_warn("removing memory fails, because memory "
1686 "[%#010llx-%#010llx] is onlined\n",
1687 PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)),
1688 PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1);
1689
1690 return ret;
1691}
1692
Tang Chen60a5a192013-02-22 16:33:14 -08001693static int check_cpu_on_node(void *data)
1694{
1695 struct pglist_data *pgdat = data;
1696 int cpu;
1697
1698 for_each_present_cpu(cpu) {
1699 if (cpu_to_node(cpu) == pgdat->node_id)
1700 /*
1701 * the cpu on this node isn't removed, and we can't
1702 * offline this node.
1703 */
1704 return -EBUSY;
1705 }
1706
1707 return 0;
1708}
1709
Wen Congyange13fe862013-02-22 16:33:31 -08001710static void unmap_cpu_on_node(void *data)
1711{
1712#ifdef CONFIG_ACPI_NUMA
1713 struct pglist_data *pgdat = data;
1714 int cpu;
1715
1716 for_each_possible_cpu(cpu)
1717 if (cpu_to_node(cpu) == pgdat->node_id)
1718 numa_clear_node(cpu);
1719#endif
1720}
1721
1722static int check_and_unmap_cpu_on_node(void *data)
1723{
1724 int ret = check_cpu_on_node(data);
1725
1726 if (ret)
1727 return ret;
1728
1729 /*
1730 * the node will be offlined when we come here, so we can clear
1731 * the cpu_to_node() now.
1732 */
1733
1734 unmap_cpu_on_node(data);
1735 return 0;
1736}
1737
Tang Chen60a5a192013-02-22 16:33:14 -08001738/* offline the node if all memory sections of this node are removed */
Wen Congyang90b30cd2013-02-22 16:33:27 -08001739void try_offline_node(int nid)
Tang Chen60a5a192013-02-22 16:33:14 -08001740{
Wen Congyangd822b862013-02-22 16:33:16 -08001741 pg_data_t *pgdat = NODE_DATA(nid);
1742 unsigned long start_pfn = pgdat->node_start_pfn;
1743 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
Tang Chen60a5a192013-02-22 16:33:14 -08001744 unsigned long pfn;
Wen Congyangd822b862013-02-22 16:33:16 -08001745 struct page *pgdat_page = virt_to_page(pgdat);
1746 int i;
Tang Chen60a5a192013-02-22 16:33:14 -08001747
1748 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
1749 unsigned long section_nr = pfn_to_section_nr(pfn);
1750
1751 if (!present_section_nr(section_nr))
1752 continue;
1753
1754 if (pfn_to_nid(pfn) != nid)
1755 continue;
1756
1757 /*
1758 * some memory sections of this node are not removed, and we
1759 * can't offline node now.
1760 */
1761 return;
1762 }
1763
Wen Congyange13fe862013-02-22 16:33:31 -08001764 if (stop_machine(check_and_unmap_cpu_on_node, pgdat, NULL))
Tang Chen60a5a192013-02-22 16:33:14 -08001765 return;
1766
1767 /*
1768 * all memory/cpu of this node are removed, we can offline this
1769 * node now.
1770 */
1771 node_set_offline(nid);
1772 unregister_one_node(nid);
Wen Congyangd822b862013-02-22 16:33:16 -08001773
1774 if (!PageSlab(pgdat_page) && !PageCompound(pgdat_page))
1775 /* node data is allocated from boot memory */
1776 return;
1777
1778 /* free waittable in each zone */
1779 for (i = 0; i < MAX_NR_ZONES; i++) {
1780 struct zone *zone = pgdat->node_zones + i;
1781
1782 if (zone->wait_table)
1783 vfree(zone->wait_table);
1784 }
1785
1786 /*
1787 * Since there is no way to guarentee the address of pgdat/zone is not
1788 * on stack of any kernel threads or used by other kernel objects
1789 * without reference counting or other symchronizing method, do not
1790 * reset node_data and free pgdat here. Just reset it to 0 and reuse
1791 * the memory when the node is online again.
1792 */
1793 memset(pgdat, 0, sizeof(*pgdat));
Tang Chen60a5a192013-02-22 16:33:14 -08001794}
Wen Congyang90b30cd2013-02-22 16:33:27 -08001795EXPORT_SYMBOL(try_offline_node);
Tang Chen60a5a192013-02-22 16:33:14 -08001796
1797int __ref remove_memory(int nid, u64 start, u64 size)
Wen Congyangbbc76be2013-02-22 16:32:54 -08001798{
1799 unsigned long start_pfn, end_pfn;
1800 int ret = 0;
1801 int retry = 1;
1802
1803 start_pfn = PFN_DOWN(start);
1804 end_pfn = start_pfn + PFN_DOWN(size);
1805
1806 /*
1807 * When CONFIG_MEMCG is on, one memory block may be used by other
1808 * blocks to store page cgroup when onlining pages. But we don't know
1809 * in what order pages are onlined. So we iterate twice to offline
1810 * memory:
1811 * 1st iterate: offline every non primary memory block.
1812 * 2nd iterate: offline primary (i.e. first added) memory block.
1813 */
1814repeat:
1815 walk_memory_range(start_pfn, end_pfn, &ret,
1816 offline_memory_block_cb);
1817 if (ret) {
1818 if (!retry)
1819 return ret;
1820
1821 retry = 0;
1822 ret = 0;
Wen Congyang993c1aa2013-02-22 16:32:50 -08001823 goto repeat;
1824 }
1825
Yasuaki Ishimatsu6677e3e2013-02-22 16:32:52 -08001826 lock_memory_hotplug();
1827
1828 /*
1829 * we have offlined all memory blocks like this:
1830 * 1. lock memory hotplug
1831 * 2. offline a memory block
1832 * 3. unlock memory hotplug
1833 *
1834 * repeat step1-3 to offline the memory block. All memory blocks
1835 * must be offlined before removing memory. But we don't hold the
1836 * lock in the whole operation. So we should check whether all
1837 * memory blocks are offlined.
1838 */
1839
Wen Congyangbbc76be2013-02-22 16:32:54 -08001840 ret = walk_memory_range(start_pfn, end_pfn, NULL,
1841 is_memblock_offlined_cb);
1842 if (ret) {
1843 unlock_memory_hotplug();
1844 return ret;
Yasuaki Ishimatsu6677e3e2013-02-22 16:32:52 -08001845 }
1846
Yasuaki Ishimatsu46c66c42013-02-22 16:32:56 -08001847 /* remove memmap entry */
1848 firmware_map_remove(start, start + size, "System RAM");
1849
Wen Congyang24d335c2013-02-22 16:32:58 -08001850 arch_remove_memory(start, size);
1851
Tang Chen60a5a192013-02-22 16:33:14 -08001852 try_offline_node(nid);
1853
Yasuaki Ishimatsu6677e3e2013-02-22 16:32:52 -08001854 unlock_memory_hotplug();
1855
Wen Congyange90bdb72012-10-08 16:34:01 -07001856 return 0;
Badari Pulavarty71088782008-10-18 20:25:58 -07001857}
KAMEZAWA Hiroyuki48e94192007-10-16 01:26:14 -07001858#else
Wen Congyanga16cee12012-10-08 16:33:58 -07001859int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
1860{
1861 return -EINVAL;
1862}
Tang Chen60a5a192013-02-22 16:33:14 -08001863int remove_memory(int nid, u64 start, u64 size)
KAMEZAWA Hiroyuki48e94192007-10-16 01:26:14 -07001864{
1865 return -EINVAL;
1866}
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07001867#endif /* CONFIG_MEMORY_HOTREMOVE */
Badari Pulavarty71088782008-10-18 20:25:58 -07001868EXPORT_SYMBOL_GPL(remove_memory);