Commit | Line | Data |
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3947be19 DH |
1 | /* |
2 | * linux/mm/memory_hotplug.c | |
3 | * | |
4 | * Copyright (C) | |
5 | */ | |
6 | ||
3947be19 DH |
7 | #include <linux/stddef.h> |
8 | #include <linux/mm.h> | |
9 | #include <linux/swap.h> | |
10 | #include <linux/interrupt.h> | |
11 | #include <linux/pagemap.h> | |
12 | #include <linux/bootmem.h> | |
13 | #include <linux/compiler.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/pagevec.h> | |
2d1d43f6 | 16 | #include <linux/writeback.h> |
3947be19 DH |
17 | #include <linux/slab.h> |
18 | #include <linux/sysctl.h> | |
19 | #include <linux/cpu.h> | |
20 | #include <linux/memory.h> | |
21 | #include <linux/memory_hotplug.h> | |
22 | #include <linux/highmem.h> | |
23 | #include <linux/vmalloc.h> | |
0a547039 | 24 | #include <linux/ioport.h> |
0c0e6195 KH |
25 | #include <linux/delay.h> |
26 | #include <linux/migrate.h> | |
27 | #include <linux/page-isolation.h> | |
71088785 | 28 | #include <linux/pfn.h> |
6ad696d2 | 29 | #include <linux/suspend.h> |
6d9c285a | 30 | #include <linux/mm_inline.h> |
3947be19 DH |
31 | |
32 | #include <asm/tlbflush.h> | |
33 | ||
1e5ad9a3 AB |
34 | #include "internal.h" |
35 | ||
45e0b78b KM |
36 | /* add this memory to iomem resource */ |
37 | static struct resource *register_memory_resource(u64 start, u64 size) | |
38 | { | |
39 | struct resource *res; | |
40 | res = kzalloc(sizeof(struct resource), GFP_KERNEL); | |
41 | BUG_ON(!res); | |
42 | ||
43 | res->name = "System RAM"; | |
44 | res->start = start; | |
45 | res->end = start + size - 1; | |
887c3cb1 | 46 | res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
45e0b78b KM |
47 | if (request_resource(&iomem_resource, res) < 0) { |
48 | printk("System RAM resource %llx - %llx cannot be added\n", | |
49 | (unsigned long long)res->start, (unsigned long long)res->end); | |
50 | kfree(res); | |
51 | res = NULL; | |
52 | } | |
53 | return res; | |
54 | } | |
55 | ||
56 | static void release_memory_resource(struct resource *res) | |
57 | { | |
58 | if (!res) | |
59 | return; | |
60 | release_resource(res); | |
61 | kfree(res); | |
62 | return; | |
63 | } | |
64 | ||
53947027 | 65 | #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE |
04753278 | 66 | #ifndef CONFIG_SPARSEMEM_VMEMMAP |
af370fb8 | 67 | static void get_page_bootmem(unsigned long info, struct page *page, int type) |
04753278 | 68 | { |
af370fb8 | 69 | atomic_set(&page->_mapcount, type); |
04753278 YG |
70 | SetPagePrivate(page); |
71 | set_page_private(page, info); | |
72 | atomic_inc(&page->_count); | |
73 | } | |
74 | ||
75 | void put_page_bootmem(struct page *page) | |
76 | { | |
af370fb8 | 77 | int type; |
04753278 | 78 | |
af370fb8 YG |
79 | type = atomic_read(&page->_mapcount); |
80 | BUG_ON(type >= -1); | |
04753278 YG |
81 | |
82 | if (atomic_dec_return(&page->_count) == 1) { | |
83 | ClearPagePrivate(page); | |
84 | set_page_private(page, 0); | |
85 | reset_page_mapcount(page); | |
86 | __free_pages_bootmem(page, 0); | |
87 | } | |
88 | ||
89 | } | |
90 | ||
d92bc318 | 91 | static void register_page_bootmem_info_section(unsigned long start_pfn) |
04753278 YG |
92 | { |
93 | unsigned long *usemap, mapsize, section_nr, i; | |
94 | struct mem_section *ms; | |
95 | struct page *page, *memmap; | |
96 | ||
97 | if (!pfn_valid(start_pfn)) | |
98 | return; | |
99 | ||
100 | section_nr = pfn_to_section_nr(start_pfn); | |
101 | ms = __nr_to_section(section_nr); | |
102 | ||
103 | /* Get section's memmap address */ | |
104 | memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); | |
105 | ||
106 | /* | |
107 | * Get page for the memmap's phys address | |
108 | * XXX: need more consideration for sparse_vmemmap... | |
109 | */ | |
110 | page = virt_to_page(memmap); | |
111 | mapsize = sizeof(struct page) * PAGES_PER_SECTION; | |
112 | mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT; | |
113 | ||
114 | /* remember memmap's page */ | |
115 | for (i = 0; i < mapsize; i++, page++) | |
116 | get_page_bootmem(section_nr, page, SECTION_INFO); | |
117 | ||
118 | usemap = __nr_to_section(section_nr)->pageblock_flags; | |
119 | page = virt_to_page(usemap); | |
120 | ||
121 | mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT; | |
122 | ||
123 | for (i = 0; i < mapsize; i++, page++) | |
af370fb8 | 124 | get_page_bootmem(section_nr, page, MIX_SECTION_INFO); |
04753278 YG |
125 | |
126 | } | |
127 | ||
128 | void register_page_bootmem_info_node(struct pglist_data *pgdat) | |
129 | { | |
130 | unsigned long i, pfn, end_pfn, nr_pages; | |
131 | int node = pgdat->node_id; | |
132 | struct page *page; | |
133 | struct zone *zone; | |
134 | ||
135 | nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT; | |
136 | page = virt_to_page(pgdat); | |
137 | ||
138 | for (i = 0; i < nr_pages; i++, page++) | |
139 | get_page_bootmem(node, page, NODE_INFO); | |
140 | ||
141 | zone = &pgdat->node_zones[0]; | |
142 | for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) { | |
143 | if (zone->wait_table) { | |
144 | nr_pages = zone->wait_table_hash_nr_entries | |
145 | * sizeof(wait_queue_head_t); | |
146 | nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT; | |
147 | page = virt_to_page(zone->wait_table); | |
148 | ||
149 | for (i = 0; i < nr_pages; i++, page++) | |
150 | get_page_bootmem(node, page, NODE_INFO); | |
151 | } | |
152 | } | |
153 | ||
154 | pfn = pgdat->node_start_pfn; | |
155 | end_pfn = pfn + pgdat->node_spanned_pages; | |
156 | ||
157 | /* register_section info */ | |
158 | for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) | |
159 | register_page_bootmem_info_section(pfn); | |
160 | ||
161 | } | |
162 | #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ | |
163 | ||
76cdd58e HC |
164 | static void grow_zone_span(struct zone *zone, unsigned long start_pfn, |
165 | unsigned long end_pfn) | |
166 | { | |
167 | unsigned long old_zone_end_pfn; | |
168 | ||
169 | zone_span_writelock(zone); | |
170 | ||
171 | old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
172 | if (start_pfn < zone->zone_start_pfn) | |
173 | zone->zone_start_pfn = start_pfn; | |
174 | ||
175 | zone->spanned_pages = max(old_zone_end_pfn, end_pfn) - | |
176 | zone->zone_start_pfn; | |
177 | ||
178 | zone_span_writeunlock(zone); | |
179 | } | |
180 | ||
181 | static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn, | |
182 | unsigned long end_pfn) | |
183 | { | |
184 | unsigned long old_pgdat_end_pfn = | |
185 | pgdat->node_start_pfn + pgdat->node_spanned_pages; | |
186 | ||
187 | if (start_pfn < pgdat->node_start_pfn) | |
188 | pgdat->node_start_pfn = start_pfn; | |
189 | ||
190 | pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) - | |
191 | pgdat->node_start_pfn; | |
192 | } | |
193 | ||
31168481 | 194 | static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn) |
3947be19 DH |
195 | { |
196 | struct pglist_data *pgdat = zone->zone_pgdat; | |
197 | int nr_pages = PAGES_PER_SECTION; | |
198 | int nid = pgdat->node_id; | |
199 | int zone_type; | |
76cdd58e | 200 | unsigned long flags; |
3947be19 DH |
201 | |
202 | zone_type = zone - pgdat->node_zones; | |
76cdd58e HC |
203 | if (!zone->wait_table) { |
204 | int ret; | |
205 | ||
206 | ret = init_currently_empty_zone(zone, phys_start_pfn, | |
207 | nr_pages, MEMMAP_HOTPLUG); | |
208 | if (ret) | |
209 | return ret; | |
210 | } | |
211 | pgdat_resize_lock(zone->zone_pgdat, &flags); | |
212 | grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages); | |
213 | grow_pgdat_span(zone->zone_pgdat, phys_start_pfn, | |
214 | phys_start_pfn + nr_pages); | |
215 | pgdat_resize_unlock(zone->zone_pgdat, &flags); | |
a2f3aa02 DH |
216 | memmap_init_zone(nr_pages, nid, zone_type, |
217 | phys_start_pfn, MEMMAP_HOTPLUG); | |
718127cc | 218 | return 0; |
3947be19 DH |
219 | } |
220 | ||
c04fc586 GH |
221 | static int __meminit __add_section(int nid, struct zone *zone, |
222 | unsigned long phys_start_pfn) | |
3947be19 | 223 | { |
3947be19 | 224 | int nr_pages = PAGES_PER_SECTION; |
3947be19 DH |
225 | int ret; |
226 | ||
ebd15302 KH |
227 | if (pfn_valid(phys_start_pfn)) |
228 | return -EEXIST; | |
229 | ||
0b0acbec | 230 | ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages); |
3947be19 DH |
231 | |
232 | if (ret < 0) | |
233 | return ret; | |
234 | ||
718127cc YG |
235 | ret = __add_zone(zone, phys_start_pfn); |
236 | ||
237 | if (ret < 0) | |
238 | return ret; | |
239 | ||
c04fc586 | 240 | return register_new_memory(nid, __pfn_to_section(phys_start_pfn)); |
3947be19 DH |
241 | } |
242 | ||
0c0a4a51 YG |
243 | #ifdef CONFIG_SPARSEMEM_VMEMMAP |
244 | static int __remove_section(struct zone *zone, struct mem_section *ms) | |
245 | { | |
246 | /* | |
247 | * XXX: Freeing memmap with vmemmap is not implement yet. | |
248 | * This should be removed later. | |
249 | */ | |
250 | return -EBUSY; | |
251 | } | |
252 | #else | |
ea01ea93 BP |
253 | static int __remove_section(struct zone *zone, struct mem_section *ms) |
254 | { | |
255 | unsigned long flags; | |
256 | struct pglist_data *pgdat = zone->zone_pgdat; | |
257 | int ret = -EINVAL; | |
258 | ||
259 | if (!valid_section(ms)) | |
260 | return ret; | |
261 | ||
262 | ret = unregister_memory_section(ms); | |
263 | if (ret) | |
264 | return ret; | |
265 | ||
266 | pgdat_resize_lock(pgdat, &flags); | |
267 | sparse_remove_one_section(zone, ms); | |
268 | pgdat_resize_unlock(pgdat, &flags); | |
269 | return 0; | |
270 | } | |
0c0a4a51 | 271 | #endif |
ea01ea93 | 272 | |
3947be19 DH |
273 | /* |
274 | * Reasonably generic function for adding memory. It is | |
275 | * expected that archs that support memory hotplug will | |
276 | * call this function after deciding the zone to which to | |
277 | * add the new pages. | |
278 | */ | |
c04fc586 GH |
279 | int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, |
280 | unsigned long nr_pages) | |
3947be19 DH |
281 | { |
282 | unsigned long i; | |
283 | int err = 0; | |
6f712711 KH |
284 | int start_sec, end_sec; |
285 | /* during initialize mem_map, align hot-added range to section */ | |
286 | start_sec = pfn_to_section_nr(phys_start_pfn); | |
287 | end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1); | |
3947be19 | 288 | |
6f712711 | 289 | for (i = start_sec; i <= end_sec; i++) { |
c04fc586 | 290 | err = __add_section(nid, zone, i << PFN_SECTION_SHIFT); |
3947be19 | 291 | |
6f712711 | 292 | /* |
183ff22b | 293 | * EEXIST is finally dealt with by ioresource collision |
6f712711 KH |
294 | * check. see add_memory() => register_memory_resource() |
295 | * Warning will be printed if there is collision. | |
bed120c6 JS |
296 | */ |
297 | if (err && (err != -EEXIST)) | |
3947be19 | 298 | break; |
6f712711 | 299 | err = 0; |
3947be19 DH |
300 | } |
301 | ||
302 | return err; | |
303 | } | |
bed120c6 | 304 | EXPORT_SYMBOL_GPL(__add_pages); |
3947be19 | 305 | |
ea01ea93 BP |
306 | /** |
307 | * __remove_pages() - remove sections of pages from a zone | |
308 | * @zone: zone from which pages need to be removed | |
309 | * @phys_start_pfn: starting pageframe (must be aligned to start of a section) | |
310 | * @nr_pages: number of pages to remove (must be multiple of section size) | |
311 | * | |
312 | * Generic helper function to remove section mappings and sysfs entries | |
313 | * for the section of the memory we are removing. Caller needs to make | |
314 | * sure that pages are marked reserved and zones are adjust properly by | |
315 | * calling offline_pages(). | |
316 | */ | |
317 | int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, | |
318 | unsigned long nr_pages) | |
319 | { | |
320 | unsigned long i, ret = 0; | |
321 | int sections_to_remove; | |
322 | ||
323 | /* | |
324 | * We can only remove entire sections | |
325 | */ | |
326 | BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); | |
327 | BUG_ON(nr_pages % PAGES_PER_SECTION); | |
328 | ||
ea01ea93 BP |
329 | sections_to_remove = nr_pages / PAGES_PER_SECTION; |
330 | for (i = 0; i < sections_to_remove; i++) { | |
331 | unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; | |
de7f0cba NF |
332 | release_mem_region(pfn << PAGE_SHIFT, |
333 | PAGES_PER_SECTION << PAGE_SHIFT); | |
ea01ea93 BP |
334 | ret = __remove_section(zone, __pfn_to_section(pfn)); |
335 | if (ret) | |
336 | break; | |
337 | } | |
338 | return ret; | |
339 | } | |
340 | EXPORT_SYMBOL_GPL(__remove_pages); | |
341 | ||
180c06ef JF |
342 | void online_page(struct page *page) |
343 | { | |
4738e1b9 JB |
344 | unsigned long pfn = page_to_pfn(page); |
345 | ||
180c06ef | 346 | totalram_pages++; |
4738e1b9 JB |
347 | if (pfn >= num_physpages) |
348 | num_physpages = pfn + 1; | |
180c06ef JF |
349 | |
350 | #ifdef CONFIG_HIGHMEM | |
351 | if (PageHighMem(page)) | |
352 | totalhigh_pages++; | |
353 | #endif | |
354 | ||
355 | #ifdef CONFIG_FLATMEM | |
356 | max_mapnr = max(page_to_pfn(page), max_mapnr); | |
357 | #endif | |
358 | ||
359 | ClearPageReserved(page); | |
360 | init_page_count(page); | |
361 | __free_page(page); | |
362 | } | |
363 | ||
75884fb1 KH |
364 | static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, |
365 | void *arg) | |
3947be19 DH |
366 | { |
367 | unsigned long i; | |
75884fb1 KH |
368 | unsigned long onlined_pages = *(unsigned long *)arg; |
369 | struct page *page; | |
370 | if (PageReserved(pfn_to_page(start_pfn))) | |
371 | for (i = 0; i < nr_pages; i++) { | |
372 | page = pfn_to_page(start_pfn + i); | |
373 | online_page(page); | |
374 | onlined_pages++; | |
375 | } | |
376 | *(unsigned long *)arg = onlined_pages; | |
377 | return 0; | |
378 | } | |
379 | ||
380 | ||
381 | int online_pages(unsigned long pfn, unsigned long nr_pages) | |
382 | { | |
3947be19 DH |
383 | unsigned long onlined_pages = 0; |
384 | struct zone *zone; | |
6811378e | 385 | int need_zonelists_rebuild = 0; |
7b78d335 YG |
386 | int nid; |
387 | int ret; | |
388 | struct memory_notify arg; | |
389 | ||
390 | arg.start_pfn = pfn; | |
391 | arg.nr_pages = nr_pages; | |
392 | arg.status_change_nid = -1; | |
393 | ||
394 | nid = page_to_nid(pfn_to_page(pfn)); | |
395 | if (node_present_pages(nid) == 0) | |
396 | arg.status_change_nid = nid; | |
3947be19 | 397 | |
7b78d335 YG |
398 | ret = memory_notify(MEM_GOING_ONLINE, &arg); |
399 | ret = notifier_to_errno(ret); | |
400 | if (ret) { | |
401 | memory_notify(MEM_CANCEL_ONLINE, &arg); | |
402 | return ret; | |
403 | } | |
3947be19 DH |
404 | /* |
405 | * This doesn't need a lock to do pfn_to_page(). | |
406 | * The section can't be removed here because of the | |
da19cbcf | 407 | * memory_block->state_mutex. |
3947be19 DH |
408 | */ |
409 | zone = page_zone(pfn_to_page(pfn)); | |
6811378e YG |
410 | /* |
411 | * If this zone is not populated, then it is not in zonelist. | |
412 | * This means the page allocator ignores this zone. | |
413 | * So, zonelist must be updated after online. | |
414 | */ | |
415 | if (!populated_zone(zone)) | |
416 | need_zonelists_rebuild = 1; | |
417 | ||
908eedc6 | 418 | ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages, |
75884fb1 | 419 | online_pages_range); |
fd8a4221 GL |
420 | if (ret) { |
421 | printk(KERN_DEBUG "online_pages %lx at %lx failed\n", | |
422 | nr_pages, pfn); | |
423 | memory_notify(MEM_CANCEL_ONLINE, &arg); | |
424 | return ret; | |
425 | } | |
426 | ||
3947be19 | 427 | zone->present_pages += onlined_pages; |
f2937be5 | 428 | zone->zone_pgdat->node_present_pages += onlined_pages; |
3947be19 | 429 | |
112067f0 | 430 | zone_pcp_update(zone); |
bc75d33f | 431 | setup_per_zone_wmarks(); |
bce7394a | 432 | calculate_zone_inactive_ratio(zone); |
7ea1530a CL |
433 | if (onlined_pages) { |
434 | kswapd_run(zone_to_nid(zone)); | |
435 | node_set_state(zone_to_nid(zone), N_HIGH_MEMORY); | |
436 | } | |
61b13993 | 437 | |
6811378e YG |
438 | if (need_zonelists_rebuild) |
439 | build_all_zonelists(); | |
2f7f24ec KL |
440 | else |
441 | vm_total_pages = nr_free_pagecache_pages(); | |
442 | ||
2d1d43f6 | 443 | writeback_set_ratelimit(); |
7b78d335 YG |
444 | |
445 | if (onlined_pages) | |
446 | memory_notify(MEM_ONLINE, &arg); | |
447 | ||
3947be19 DH |
448 | return 0; |
449 | } | |
53947027 | 450 | #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ |
bc02af93 | 451 | |
e1319331 HS |
452 | /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ |
453 | static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) | |
9af3c2de YG |
454 | { |
455 | struct pglist_data *pgdat; | |
456 | unsigned long zones_size[MAX_NR_ZONES] = {0}; | |
457 | unsigned long zholes_size[MAX_NR_ZONES] = {0}; | |
458 | unsigned long start_pfn = start >> PAGE_SHIFT; | |
459 | ||
460 | pgdat = arch_alloc_nodedata(nid); | |
461 | if (!pgdat) | |
462 | return NULL; | |
463 | ||
464 | arch_refresh_nodedata(nid, pgdat); | |
465 | ||
466 | /* we can use NODE_DATA(nid) from here */ | |
467 | ||
468 | /* init node's zones as empty zones, we don't have any present pages.*/ | |
9109fb7b | 469 | free_area_init_node(nid, zones_size, start_pfn, zholes_size); |
9af3c2de YG |
470 | |
471 | return pgdat; | |
472 | } | |
473 | ||
474 | static void rollback_node_hotadd(int nid, pg_data_t *pgdat) | |
475 | { | |
476 | arch_refresh_nodedata(nid, NULL); | |
477 | arch_free_nodedata(pgdat); | |
478 | return; | |
479 | } | |
480 | ||
0a547039 | 481 | |
31168481 AV |
482 | /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ |
483 | int __ref add_memory(int nid, u64 start, u64 size) | |
bc02af93 | 484 | { |
9af3c2de YG |
485 | pg_data_t *pgdat = NULL; |
486 | int new_pgdat = 0; | |
ebd15302 | 487 | struct resource *res; |
bc02af93 YG |
488 | int ret; |
489 | ||
6ad696d2 AK |
490 | lock_system_sleep(); |
491 | ||
ebd15302 | 492 | res = register_memory_resource(start, size); |
6ad696d2 | 493 | ret = -EEXIST; |
ebd15302 | 494 | if (!res) |
6ad696d2 | 495 | goto out; |
ebd15302 | 496 | |
9af3c2de YG |
497 | if (!node_online(nid)) { |
498 | pgdat = hotadd_new_pgdat(nid, start); | |
6ad696d2 | 499 | ret = -ENOMEM; |
9af3c2de | 500 | if (!pgdat) |
6ad696d2 | 501 | goto out; |
9af3c2de | 502 | new_pgdat = 1; |
9af3c2de YG |
503 | } |
504 | ||
bc02af93 YG |
505 | /* call arch's memory hotadd */ |
506 | ret = arch_add_memory(nid, start, size); | |
507 | ||
9af3c2de YG |
508 | if (ret < 0) |
509 | goto error; | |
510 | ||
0fc44159 | 511 | /* we online node here. we can't roll back from here. */ |
9af3c2de YG |
512 | node_set_online(nid); |
513 | ||
0fc44159 YG |
514 | if (new_pgdat) { |
515 | ret = register_one_node(nid); | |
516 | /* | |
517 | * If sysfs file of new node can't create, cpu on the node | |
518 | * can't be hot-added. There is no rollback way now. | |
519 | * So, check by BUG_ON() to catch it reluctantly.. | |
520 | */ | |
521 | BUG_ON(ret); | |
522 | } | |
523 | ||
6ad696d2 AK |
524 | goto out; |
525 | ||
9af3c2de YG |
526 | error: |
527 | /* rollback pgdat allocation and others */ | |
528 | if (new_pgdat) | |
529 | rollback_node_hotadd(nid, pgdat); | |
ebd15302 KH |
530 | if (res) |
531 | release_memory_resource(res); | |
9af3c2de | 532 | |
6ad696d2 AK |
533 | out: |
534 | unlock_system_sleep(); | |
bc02af93 YG |
535 | return ret; |
536 | } | |
537 | EXPORT_SYMBOL_GPL(add_memory); | |
0c0e6195 KH |
538 | |
539 | #ifdef CONFIG_MEMORY_HOTREMOVE | |
5c755e9f BP |
540 | /* |
541 | * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy | |
542 | * set and the size of the free page is given by page_order(). Using this, | |
543 | * the function determines if the pageblock contains only free pages. | |
544 | * Due to buddy contraints, a free page at least the size of a pageblock will | |
545 | * be located at the start of the pageblock | |
546 | */ | |
547 | static inline int pageblock_free(struct page *page) | |
548 | { | |
549 | return PageBuddy(page) && page_order(page) >= pageblock_order; | |
550 | } | |
551 | ||
552 | /* Return the start of the next active pageblock after a given page */ | |
553 | static struct page *next_active_pageblock(struct page *page) | |
554 | { | |
555 | int pageblocks_stride; | |
556 | ||
557 | /* Ensure the starting page is pageblock-aligned */ | |
558 | BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1)); | |
559 | ||
560 | /* Move forward by at least 1 * pageblock_nr_pages */ | |
561 | pageblocks_stride = 1; | |
562 | ||
563 | /* If the entire pageblock is free, move to the end of free page */ | |
564 | if (pageblock_free(page)) | |
565 | pageblocks_stride += page_order(page) - pageblock_order; | |
566 | ||
567 | return page + (pageblocks_stride * pageblock_nr_pages); | |
568 | } | |
569 | ||
570 | /* Checks if this range of memory is likely to be hot-removable. */ | |
571 | int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) | |
572 | { | |
573 | int type; | |
574 | struct page *page = pfn_to_page(start_pfn); | |
575 | struct page *end_page = page + nr_pages; | |
576 | ||
577 | /* Check the starting page of each pageblock within the range */ | |
578 | for (; page < end_page; page = next_active_pageblock(page)) { | |
579 | type = get_pageblock_migratetype(page); | |
580 | ||
581 | /* | |
582 | * A pageblock containing MOVABLE or free pages is considered | |
583 | * removable | |
584 | */ | |
585 | if (type != MIGRATE_MOVABLE && !pageblock_free(page)) | |
586 | return 0; | |
587 | ||
588 | /* | |
589 | * A pageblock starting with a PageReserved page is not | |
590 | * considered removable. | |
591 | */ | |
592 | if (PageReserved(page)) | |
593 | return 0; | |
594 | } | |
595 | ||
596 | /* All pageblocks in the memory block are likely to be hot-removable */ | |
597 | return 1; | |
598 | } | |
599 | ||
0c0e6195 KH |
600 | /* |
601 | * Confirm all pages in a range [start, end) is belongs to the same zone. | |
602 | */ | |
603 | static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) | |
604 | { | |
605 | unsigned long pfn; | |
606 | struct zone *zone = NULL; | |
607 | struct page *page; | |
608 | int i; | |
609 | for (pfn = start_pfn; | |
610 | pfn < end_pfn; | |
611 | pfn += MAX_ORDER_NR_PAGES) { | |
612 | i = 0; | |
613 | /* This is just a CONFIG_HOLES_IN_ZONE check.*/ | |
614 | while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) | |
615 | i++; | |
616 | if (i == MAX_ORDER_NR_PAGES) | |
617 | continue; | |
618 | page = pfn_to_page(pfn + i); | |
619 | if (zone && page_zone(page) != zone) | |
620 | return 0; | |
621 | zone = page_zone(page); | |
622 | } | |
623 | return 1; | |
624 | } | |
625 | ||
626 | /* | |
627 | * Scanning pfn is much easier than scanning lru list. | |
628 | * Scan pfn from start to end and Find LRU page. | |
629 | */ | |
630 | int scan_lru_pages(unsigned long start, unsigned long end) | |
631 | { | |
632 | unsigned long pfn; | |
633 | struct page *page; | |
634 | for (pfn = start; pfn < end; pfn++) { | |
635 | if (pfn_valid(pfn)) { | |
636 | page = pfn_to_page(pfn); | |
637 | if (PageLRU(page)) | |
638 | return pfn; | |
639 | } | |
640 | } | |
641 | return 0; | |
642 | } | |
643 | ||
644 | static struct page * | |
3c1d4378 | 645 | hotremove_migrate_alloc(struct page *page, unsigned long private, int **x) |
0c0e6195 | 646 | { |
3c1d4378 HD |
647 | /* This should be improooooved!! */ |
648 | return alloc_page(GFP_HIGHUSER_MOVABLE); | |
0c0e6195 KH |
649 | } |
650 | ||
0c0e6195 KH |
651 | #define NR_OFFLINE_AT_ONCE_PAGES (256) |
652 | static int | |
653 | do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) | |
654 | { | |
655 | unsigned long pfn; | |
656 | struct page *page; | |
657 | int move_pages = NR_OFFLINE_AT_ONCE_PAGES; | |
658 | int not_managed = 0; | |
659 | int ret = 0; | |
660 | LIST_HEAD(source); | |
661 | ||
662 | for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) { | |
663 | if (!pfn_valid(pfn)) | |
664 | continue; | |
665 | page = pfn_to_page(pfn); | |
666 | if (!page_count(page)) | |
667 | continue; | |
668 | /* | |
669 | * We can skip free pages. And we can only deal with pages on | |
670 | * LRU. | |
671 | */ | |
62695a84 | 672 | ret = isolate_lru_page(page); |
0c0e6195 | 673 | if (!ret) { /* Success */ |
62695a84 | 674 | list_add_tail(&page->lru, &source); |
0c0e6195 | 675 | move_pages--; |
6d9c285a KM |
676 | inc_zone_page_state(page, NR_ISOLATED_ANON + |
677 | page_is_file_cache(page)); | |
678 | ||
0c0e6195 KH |
679 | } else { |
680 | /* Becasue we don't have big zone->lock. we should | |
681 | check this again here. */ | |
682 | if (page_count(page)) | |
683 | not_managed++; | |
684 | #ifdef CONFIG_DEBUG_VM | |
685 | printk(KERN_INFO "removing from LRU failed" | |
686 | " %lx/%d/%lx\n", | |
687 | pfn, page_count(page), page->flags); | |
688 | #endif | |
689 | } | |
690 | } | |
691 | ret = -EBUSY; | |
692 | if (not_managed) { | |
693 | if (!list_empty(&source)) | |
694 | putback_lru_pages(&source); | |
695 | goto out; | |
696 | } | |
697 | ret = 0; | |
698 | if (list_empty(&source)) | |
699 | goto out; | |
700 | /* this function returns # of failed pages */ | |
62b61f61 | 701 | ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1); |
0c0e6195 KH |
702 | |
703 | out: | |
704 | return ret; | |
705 | } | |
706 | ||
707 | /* | |
708 | * remove from free_area[] and mark all as Reserved. | |
709 | */ | |
710 | static int | |
711 | offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages, | |
712 | void *data) | |
713 | { | |
714 | __offline_isolated_pages(start, start + nr_pages); | |
715 | return 0; | |
716 | } | |
717 | ||
718 | static void | |
719 | offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) | |
720 | { | |
908eedc6 | 721 | walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL, |
0c0e6195 KH |
722 | offline_isolated_pages_cb); |
723 | } | |
724 | ||
725 | /* | |
726 | * Check all pages in range, recoreded as memory resource, are isolated. | |
727 | */ | |
728 | static int | |
729 | check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages, | |
730 | void *data) | |
731 | { | |
732 | int ret; | |
733 | long offlined = *(long *)data; | |
734 | ret = test_pages_isolated(start_pfn, start_pfn + nr_pages); | |
735 | offlined = nr_pages; | |
736 | if (!ret) | |
737 | *(long *)data += offlined; | |
738 | return ret; | |
739 | } | |
740 | ||
741 | static long | |
742 | check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn) | |
743 | { | |
744 | long offlined = 0; | |
745 | int ret; | |
746 | ||
908eedc6 | 747 | ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined, |
0c0e6195 KH |
748 | check_pages_isolated_cb); |
749 | if (ret < 0) | |
750 | offlined = (long)ret; | |
751 | return offlined; | |
752 | } | |
753 | ||
b4e655a4 | 754 | static int offline_pages(unsigned long start_pfn, |
0c0e6195 KH |
755 | unsigned long end_pfn, unsigned long timeout) |
756 | { | |
757 | unsigned long pfn, nr_pages, expire; | |
758 | long offlined_pages; | |
7b78d335 | 759 | int ret, drain, retry_max, node; |
0c0e6195 | 760 | struct zone *zone; |
7b78d335 | 761 | struct memory_notify arg; |
0c0e6195 KH |
762 | |
763 | BUG_ON(start_pfn >= end_pfn); | |
764 | /* at least, alignment against pageblock is necessary */ | |
765 | if (!IS_ALIGNED(start_pfn, pageblock_nr_pages)) | |
766 | return -EINVAL; | |
767 | if (!IS_ALIGNED(end_pfn, pageblock_nr_pages)) | |
768 | return -EINVAL; | |
769 | /* This makes hotplug much easier...and readable. | |
770 | we assume this for now. .*/ | |
771 | if (!test_pages_in_a_zone(start_pfn, end_pfn)) | |
772 | return -EINVAL; | |
7b78d335 | 773 | |
6ad696d2 AK |
774 | lock_system_sleep(); |
775 | ||
7b78d335 YG |
776 | zone = page_zone(pfn_to_page(start_pfn)); |
777 | node = zone_to_nid(zone); | |
778 | nr_pages = end_pfn - start_pfn; | |
779 | ||
0c0e6195 KH |
780 | /* set above range as isolated */ |
781 | ret = start_isolate_page_range(start_pfn, end_pfn); | |
782 | if (ret) | |
6ad696d2 | 783 | goto out; |
7b78d335 YG |
784 | |
785 | arg.start_pfn = start_pfn; | |
786 | arg.nr_pages = nr_pages; | |
787 | arg.status_change_nid = -1; | |
788 | if (nr_pages >= node_present_pages(node)) | |
789 | arg.status_change_nid = node; | |
790 | ||
791 | ret = memory_notify(MEM_GOING_OFFLINE, &arg); | |
792 | ret = notifier_to_errno(ret); | |
793 | if (ret) | |
794 | goto failed_removal; | |
795 | ||
0c0e6195 KH |
796 | pfn = start_pfn; |
797 | expire = jiffies + timeout; | |
798 | drain = 0; | |
799 | retry_max = 5; | |
800 | repeat: | |
801 | /* start memory hot removal */ | |
802 | ret = -EAGAIN; | |
803 | if (time_after(jiffies, expire)) | |
804 | goto failed_removal; | |
805 | ret = -EINTR; | |
806 | if (signal_pending(current)) | |
807 | goto failed_removal; | |
808 | ret = 0; | |
809 | if (drain) { | |
810 | lru_add_drain_all(); | |
811 | flush_scheduled_work(); | |
812 | cond_resched(); | |
9f8f2172 | 813 | drain_all_pages(); |
0c0e6195 KH |
814 | } |
815 | ||
816 | pfn = scan_lru_pages(start_pfn, end_pfn); | |
817 | if (pfn) { /* We have page on LRU */ | |
818 | ret = do_migrate_range(pfn, end_pfn); | |
819 | if (!ret) { | |
820 | drain = 1; | |
821 | goto repeat; | |
822 | } else { | |
823 | if (ret < 0) | |
824 | if (--retry_max == 0) | |
825 | goto failed_removal; | |
826 | yield(); | |
827 | drain = 1; | |
828 | goto repeat; | |
829 | } | |
830 | } | |
831 | /* drain all zone's lru pagevec, this is asyncronous... */ | |
832 | lru_add_drain_all(); | |
833 | flush_scheduled_work(); | |
834 | yield(); | |
835 | /* drain pcp pages , this is synchrouns. */ | |
9f8f2172 | 836 | drain_all_pages(); |
0c0e6195 KH |
837 | /* check again */ |
838 | offlined_pages = check_pages_isolated(start_pfn, end_pfn); | |
839 | if (offlined_pages < 0) { | |
840 | ret = -EBUSY; | |
841 | goto failed_removal; | |
842 | } | |
843 | printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages); | |
844 | /* Ok, all of our target is islaoted. | |
845 | We cannot do rollback at this point. */ | |
846 | offline_isolated_pages(start_pfn, end_pfn); | |
dbc0e4ce KH |
847 | /* reset pagetype flags and makes migrate type to be MOVABLE */ |
848 | undo_isolate_page_range(start_pfn, end_pfn); | |
0c0e6195 | 849 | /* removal success */ |
0c0e6195 KH |
850 | zone->present_pages -= offlined_pages; |
851 | zone->zone_pgdat->node_present_pages -= offlined_pages; | |
852 | totalram_pages -= offlined_pages; | |
7b78d335 | 853 | |
bce7394a MK |
854 | setup_per_zone_wmarks(); |
855 | calculate_zone_inactive_ratio(zone); | |
8fe23e05 DR |
856 | if (!node_present_pages(node)) { |
857 | node_clear_state(node, N_HIGH_MEMORY); | |
858 | kswapd_stop(node); | |
859 | } | |
bce7394a | 860 | |
0c0e6195 KH |
861 | vm_total_pages = nr_free_pagecache_pages(); |
862 | writeback_set_ratelimit(); | |
7b78d335 YG |
863 | |
864 | memory_notify(MEM_OFFLINE, &arg); | |
6ad696d2 | 865 | unlock_system_sleep(); |
0c0e6195 KH |
866 | return 0; |
867 | ||
868 | failed_removal: | |
869 | printk(KERN_INFO "memory offlining %lx to %lx failed\n", | |
870 | start_pfn, end_pfn); | |
7b78d335 | 871 | memory_notify(MEM_CANCEL_OFFLINE, &arg); |
0c0e6195 KH |
872 | /* pushback to free area */ |
873 | undo_isolate_page_range(start_pfn, end_pfn); | |
7b78d335 | 874 | |
6ad696d2 AK |
875 | out: |
876 | unlock_system_sleep(); | |
0c0e6195 KH |
877 | return ret; |
878 | } | |
71088785 BP |
879 | |
880 | int remove_memory(u64 start, u64 size) | |
881 | { | |
882 | unsigned long start_pfn, end_pfn; | |
883 | ||
884 | start_pfn = PFN_DOWN(start); | |
885 | end_pfn = start_pfn + PFN_DOWN(size); | |
886 | return offline_pages(start_pfn, end_pfn, 120 * HZ); | |
887 | } | |
48e94196 KH |
888 | #else |
889 | int remove_memory(u64 start, u64 size) | |
890 | { | |
891 | return -EINVAL; | |
892 | } | |
0c0e6195 | 893 | #endif /* CONFIG_MEMORY_HOTREMOVE */ |
71088785 | 894 | EXPORT_SYMBOL_GPL(remove_memory); |