Commit | Line | Data |
---|---|---|
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> |
d96ae530 | 31 | #include <linux/firmware-map.h> |
3947be19 DH |
32 | |
33 | #include <asm/tlbflush.h> | |
34 | ||
1e5ad9a3 AB |
35 | #include "internal.h" |
36 | ||
45e0b78b KM |
37 | /* add this memory to iomem resource */ |
38 | static struct resource *register_memory_resource(u64 start, u64 size) | |
39 | { | |
40 | struct resource *res; | |
41 | res = kzalloc(sizeof(struct resource), GFP_KERNEL); | |
42 | BUG_ON(!res); | |
43 | ||
44 | res->name = "System RAM"; | |
45 | res->start = start; | |
46 | res->end = start + size - 1; | |
887c3cb1 | 47 | res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
45e0b78b KM |
48 | if (request_resource(&iomem_resource, res) < 0) { |
49 | printk("System RAM resource %llx - %llx cannot be added\n", | |
50 | (unsigned long long)res->start, (unsigned long long)res->end); | |
51 | kfree(res); | |
52 | res = NULL; | |
53 | } | |
54 | return res; | |
55 | } | |
56 | ||
57 | static void release_memory_resource(struct resource *res) | |
58 | { | |
59 | if (!res) | |
60 | return; | |
61 | release_resource(res); | |
62 | kfree(res); | |
63 | return; | |
64 | } | |
65 | ||
53947027 | 66 | #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE |
04753278 | 67 | #ifndef CONFIG_SPARSEMEM_VMEMMAP |
af370fb8 | 68 | static void get_page_bootmem(unsigned long info, struct page *page, int type) |
04753278 | 69 | { |
af370fb8 | 70 | atomic_set(&page->_mapcount, type); |
04753278 YG |
71 | SetPagePrivate(page); |
72 | set_page_private(page, info); | |
73 | atomic_inc(&page->_count); | |
74 | } | |
75 | ||
23ce932a RM |
76 | /* reference to __meminit __free_pages_bootmem is valid |
77 | * so use __ref to tell modpost not to generate a warning */ | |
78 | void __ref put_page_bootmem(struct page *page) | |
04753278 | 79 | { |
af370fb8 | 80 | int type; |
04753278 | 81 | |
af370fb8 YG |
82 | type = atomic_read(&page->_mapcount); |
83 | BUG_ON(type >= -1); | |
04753278 YG |
84 | |
85 | if (atomic_dec_return(&page->_count) == 1) { | |
86 | ClearPagePrivate(page); | |
87 | set_page_private(page, 0); | |
88 | reset_page_mapcount(page); | |
89 | __free_pages_bootmem(page, 0); | |
90 | } | |
91 | ||
92 | } | |
93 | ||
d92bc318 | 94 | static void register_page_bootmem_info_section(unsigned long start_pfn) |
04753278 YG |
95 | { |
96 | unsigned long *usemap, mapsize, section_nr, i; | |
97 | struct mem_section *ms; | |
98 | struct page *page, *memmap; | |
99 | ||
100 | if (!pfn_valid(start_pfn)) | |
101 | return; | |
102 | ||
103 | section_nr = pfn_to_section_nr(start_pfn); | |
104 | ms = __nr_to_section(section_nr); | |
105 | ||
106 | /* Get section's memmap address */ | |
107 | memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); | |
108 | ||
109 | /* | |
110 | * Get page for the memmap's phys address | |
111 | * XXX: need more consideration for sparse_vmemmap... | |
112 | */ | |
113 | page = virt_to_page(memmap); | |
114 | mapsize = sizeof(struct page) * PAGES_PER_SECTION; | |
115 | mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT; | |
116 | ||
117 | /* remember memmap's page */ | |
118 | for (i = 0; i < mapsize; i++, page++) | |
119 | get_page_bootmem(section_nr, page, SECTION_INFO); | |
120 | ||
121 | usemap = __nr_to_section(section_nr)->pageblock_flags; | |
122 | page = virt_to_page(usemap); | |
123 | ||
124 | mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT; | |
125 | ||
126 | for (i = 0; i < mapsize; i++, page++) | |
af370fb8 | 127 | get_page_bootmem(section_nr, page, MIX_SECTION_INFO); |
04753278 YG |
128 | |
129 | } | |
130 | ||
131 | void register_page_bootmem_info_node(struct pglist_data *pgdat) | |
132 | { | |
133 | unsigned long i, pfn, end_pfn, nr_pages; | |
134 | int node = pgdat->node_id; | |
135 | struct page *page; | |
136 | struct zone *zone; | |
137 | ||
138 | nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT; | |
139 | page = virt_to_page(pgdat); | |
140 | ||
141 | for (i = 0; i < nr_pages; i++, page++) | |
142 | get_page_bootmem(node, page, NODE_INFO); | |
143 | ||
144 | zone = &pgdat->node_zones[0]; | |
145 | for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) { | |
146 | if (zone->wait_table) { | |
147 | nr_pages = zone->wait_table_hash_nr_entries | |
148 | * sizeof(wait_queue_head_t); | |
149 | nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT; | |
150 | page = virt_to_page(zone->wait_table); | |
151 | ||
152 | for (i = 0; i < nr_pages; i++, page++) | |
153 | get_page_bootmem(node, page, NODE_INFO); | |
154 | } | |
155 | } | |
156 | ||
157 | pfn = pgdat->node_start_pfn; | |
158 | end_pfn = pfn + pgdat->node_spanned_pages; | |
159 | ||
160 | /* register_section info */ | |
161 | for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) | |
162 | register_page_bootmem_info_section(pfn); | |
163 | ||
164 | } | |
165 | #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ | |
166 | ||
76cdd58e HC |
167 | static void grow_zone_span(struct zone *zone, unsigned long start_pfn, |
168 | unsigned long end_pfn) | |
169 | { | |
170 | unsigned long old_zone_end_pfn; | |
171 | ||
172 | zone_span_writelock(zone); | |
173 | ||
174 | old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages; | |
175 | if (start_pfn < zone->zone_start_pfn) | |
176 | zone->zone_start_pfn = start_pfn; | |
177 | ||
178 | zone->spanned_pages = max(old_zone_end_pfn, end_pfn) - | |
179 | zone->zone_start_pfn; | |
180 | ||
181 | zone_span_writeunlock(zone); | |
182 | } | |
183 | ||
184 | static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn, | |
185 | unsigned long end_pfn) | |
186 | { | |
187 | unsigned long old_pgdat_end_pfn = | |
188 | pgdat->node_start_pfn + pgdat->node_spanned_pages; | |
189 | ||
190 | if (start_pfn < pgdat->node_start_pfn) | |
191 | pgdat->node_start_pfn = start_pfn; | |
192 | ||
193 | pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) - | |
194 | pgdat->node_start_pfn; | |
195 | } | |
196 | ||
31168481 | 197 | static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn) |
3947be19 DH |
198 | { |
199 | struct pglist_data *pgdat = zone->zone_pgdat; | |
200 | int nr_pages = PAGES_PER_SECTION; | |
201 | int nid = pgdat->node_id; | |
202 | int zone_type; | |
76cdd58e | 203 | unsigned long flags; |
3947be19 DH |
204 | |
205 | zone_type = zone - pgdat->node_zones; | |
76cdd58e HC |
206 | if (!zone->wait_table) { |
207 | int ret; | |
208 | ||
209 | ret = init_currently_empty_zone(zone, phys_start_pfn, | |
210 | nr_pages, MEMMAP_HOTPLUG); | |
211 | if (ret) | |
212 | return ret; | |
213 | } | |
214 | pgdat_resize_lock(zone->zone_pgdat, &flags); | |
215 | grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages); | |
216 | grow_pgdat_span(zone->zone_pgdat, phys_start_pfn, | |
217 | phys_start_pfn + nr_pages); | |
218 | pgdat_resize_unlock(zone->zone_pgdat, &flags); | |
a2f3aa02 DH |
219 | memmap_init_zone(nr_pages, nid, zone_type, |
220 | phys_start_pfn, MEMMAP_HOTPLUG); | |
718127cc | 221 | return 0; |
3947be19 DH |
222 | } |
223 | ||
c04fc586 GH |
224 | static int __meminit __add_section(int nid, struct zone *zone, |
225 | unsigned long phys_start_pfn) | |
3947be19 | 226 | { |
3947be19 | 227 | int nr_pages = PAGES_PER_SECTION; |
3947be19 DH |
228 | int ret; |
229 | ||
ebd15302 KH |
230 | if (pfn_valid(phys_start_pfn)) |
231 | return -EEXIST; | |
232 | ||
0b0acbec | 233 | ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages); |
3947be19 DH |
234 | |
235 | if (ret < 0) | |
236 | return ret; | |
237 | ||
718127cc YG |
238 | ret = __add_zone(zone, phys_start_pfn); |
239 | ||
240 | if (ret < 0) | |
241 | return ret; | |
242 | ||
c04fc586 | 243 | return register_new_memory(nid, __pfn_to_section(phys_start_pfn)); |
3947be19 DH |
244 | } |
245 | ||
0c0a4a51 YG |
246 | #ifdef CONFIG_SPARSEMEM_VMEMMAP |
247 | static int __remove_section(struct zone *zone, struct mem_section *ms) | |
248 | { | |
249 | /* | |
250 | * XXX: Freeing memmap with vmemmap is not implement yet. | |
251 | * This should be removed later. | |
252 | */ | |
253 | return -EBUSY; | |
254 | } | |
255 | #else | |
ea01ea93 BP |
256 | static int __remove_section(struct zone *zone, struct mem_section *ms) |
257 | { | |
258 | unsigned long flags; | |
259 | struct pglist_data *pgdat = zone->zone_pgdat; | |
260 | int ret = -EINVAL; | |
261 | ||
262 | if (!valid_section(ms)) | |
263 | return ret; | |
264 | ||
265 | ret = unregister_memory_section(ms); | |
266 | if (ret) | |
267 | return ret; | |
268 | ||
269 | pgdat_resize_lock(pgdat, &flags); | |
270 | sparse_remove_one_section(zone, ms); | |
271 | pgdat_resize_unlock(pgdat, &flags); | |
272 | return 0; | |
273 | } | |
0c0a4a51 | 274 | #endif |
ea01ea93 | 275 | |
3947be19 DH |
276 | /* |
277 | * Reasonably generic function for adding memory. It is | |
278 | * expected that archs that support memory hotplug will | |
279 | * call this function after deciding the zone to which to | |
280 | * add the new pages. | |
281 | */ | |
c04fc586 GH |
282 | int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, |
283 | unsigned long nr_pages) | |
3947be19 DH |
284 | { |
285 | unsigned long i; | |
286 | int err = 0; | |
6f712711 KH |
287 | int start_sec, end_sec; |
288 | /* during initialize mem_map, align hot-added range to section */ | |
289 | start_sec = pfn_to_section_nr(phys_start_pfn); | |
290 | end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1); | |
3947be19 | 291 | |
6f712711 | 292 | for (i = start_sec; i <= end_sec; i++) { |
c04fc586 | 293 | err = __add_section(nid, zone, i << PFN_SECTION_SHIFT); |
3947be19 | 294 | |
6f712711 | 295 | /* |
183ff22b | 296 | * EEXIST is finally dealt with by ioresource collision |
6f712711 KH |
297 | * check. see add_memory() => register_memory_resource() |
298 | * Warning will be printed if there is collision. | |
bed120c6 JS |
299 | */ |
300 | if (err && (err != -EEXIST)) | |
3947be19 | 301 | break; |
6f712711 | 302 | err = 0; |
3947be19 DH |
303 | } |
304 | ||
305 | return err; | |
306 | } | |
bed120c6 | 307 | EXPORT_SYMBOL_GPL(__add_pages); |
3947be19 | 308 | |
ea01ea93 BP |
309 | /** |
310 | * __remove_pages() - remove sections of pages from a zone | |
311 | * @zone: zone from which pages need to be removed | |
312 | * @phys_start_pfn: starting pageframe (must be aligned to start of a section) | |
313 | * @nr_pages: number of pages to remove (must be multiple of section size) | |
314 | * | |
315 | * Generic helper function to remove section mappings and sysfs entries | |
316 | * for the section of the memory we are removing. Caller needs to make | |
317 | * sure that pages are marked reserved and zones are adjust properly by | |
318 | * calling offline_pages(). | |
319 | */ | |
320 | int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, | |
321 | unsigned long nr_pages) | |
322 | { | |
323 | unsigned long i, ret = 0; | |
324 | int sections_to_remove; | |
325 | ||
326 | /* | |
327 | * We can only remove entire sections | |
328 | */ | |
329 | BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); | |
330 | BUG_ON(nr_pages % PAGES_PER_SECTION); | |
331 | ||
ea01ea93 BP |
332 | sections_to_remove = nr_pages / PAGES_PER_SECTION; |
333 | for (i = 0; i < sections_to_remove; i++) { | |
334 | unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; | |
de7f0cba NF |
335 | release_mem_region(pfn << PAGE_SHIFT, |
336 | PAGES_PER_SECTION << PAGE_SHIFT); | |
ea01ea93 BP |
337 | ret = __remove_section(zone, __pfn_to_section(pfn)); |
338 | if (ret) | |
339 | break; | |
340 | } | |
341 | return ret; | |
342 | } | |
343 | EXPORT_SYMBOL_GPL(__remove_pages); | |
344 | ||
180c06ef JF |
345 | void online_page(struct page *page) |
346 | { | |
4738e1b9 JB |
347 | unsigned long pfn = page_to_pfn(page); |
348 | ||
180c06ef | 349 | totalram_pages++; |
4738e1b9 JB |
350 | if (pfn >= num_physpages) |
351 | num_physpages = pfn + 1; | |
180c06ef JF |
352 | |
353 | #ifdef CONFIG_HIGHMEM | |
354 | if (PageHighMem(page)) | |
355 | totalhigh_pages++; | |
356 | #endif | |
357 | ||
358 | #ifdef CONFIG_FLATMEM | |
359 | max_mapnr = max(page_to_pfn(page), max_mapnr); | |
360 | #endif | |
361 | ||
362 | ClearPageReserved(page); | |
363 | init_page_count(page); | |
364 | __free_page(page); | |
365 | } | |
366 | ||
75884fb1 KH |
367 | static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, |
368 | void *arg) | |
3947be19 DH |
369 | { |
370 | unsigned long i; | |
75884fb1 KH |
371 | unsigned long onlined_pages = *(unsigned long *)arg; |
372 | struct page *page; | |
373 | if (PageReserved(pfn_to_page(start_pfn))) | |
374 | for (i = 0; i < nr_pages; i++) { | |
375 | page = pfn_to_page(start_pfn + i); | |
376 | online_page(page); | |
377 | onlined_pages++; | |
378 | } | |
379 | *(unsigned long *)arg = onlined_pages; | |
380 | return 0; | |
381 | } | |
382 | ||
383 | ||
384 | int online_pages(unsigned long pfn, unsigned long nr_pages) | |
385 | { | |
3947be19 DH |
386 | unsigned long onlined_pages = 0; |
387 | struct zone *zone; | |
6811378e | 388 | int need_zonelists_rebuild = 0; |
7b78d335 YG |
389 | int nid; |
390 | int ret; | |
391 | struct memory_notify arg; | |
392 | ||
393 | arg.start_pfn = pfn; | |
394 | arg.nr_pages = nr_pages; | |
395 | arg.status_change_nid = -1; | |
396 | ||
397 | nid = page_to_nid(pfn_to_page(pfn)); | |
398 | if (node_present_pages(nid) == 0) | |
399 | arg.status_change_nid = nid; | |
3947be19 | 400 | |
7b78d335 YG |
401 | ret = memory_notify(MEM_GOING_ONLINE, &arg); |
402 | ret = notifier_to_errno(ret); | |
403 | if (ret) { | |
404 | memory_notify(MEM_CANCEL_ONLINE, &arg); | |
405 | return ret; | |
406 | } | |
3947be19 DH |
407 | /* |
408 | * This doesn't need a lock to do pfn_to_page(). | |
409 | * The section can't be removed here because of the | |
da19cbcf | 410 | * memory_block->state_mutex. |
3947be19 DH |
411 | */ |
412 | zone = page_zone(pfn_to_page(pfn)); | |
6811378e YG |
413 | /* |
414 | * If this zone is not populated, then it is not in zonelist. | |
415 | * This means the page allocator ignores this zone. | |
416 | * So, zonelist must be updated after online. | |
417 | */ | |
418 | if (!populated_zone(zone)) | |
419 | need_zonelists_rebuild = 1; | |
420 | ||
908eedc6 | 421 | ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages, |
75884fb1 | 422 | online_pages_range); |
fd8a4221 GL |
423 | if (ret) { |
424 | printk(KERN_DEBUG "online_pages %lx at %lx failed\n", | |
425 | nr_pages, pfn); | |
426 | memory_notify(MEM_CANCEL_ONLINE, &arg); | |
427 | return ret; | |
428 | } | |
429 | ||
3947be19 | 430 | zone->present_pages += onlined_pages; |
f2937be5 | 431 | zone->zone_pgdat->node_present_pages += onlined_pages; |
3947be19 | 432 | |
112067f0 | 433 | zone_pcp_update(zone); |
bc75d33f | 434 | setup_per_zone_wmarks(); |
bce7394a | 435 | calculate_zone_inactive_ratio(zone); |
7ea1530a CL |
436 | if (onlined_pages) { |
437 | kswapd_run(zone_to_nid(zone)); | |
438 | node_set_state(zone_to_nid(zone), N_HIGH_MEMORY); | |
439 | } | |
61b13993 | 440 | |
6811378e YG |
441 | if (need_zonelists_rebuild) |
442 | build_all_zonelists(); | |
2f7f24ec KL |
443 | else |
444 | vm_total_pages = nr_free_pagecache_pages(); | |
445 | ||
2d1d43f6 | 446 | writeback_set_ratelimit(); |
7b78d335 YG |
447 | |
448 | if (onlined_pages) | |
449 | memory_notify(MEM_ONLINE, &arg); | |
450 | ||
3947be19 DH |
451 | return 0; |
452 | } | |
53947027 | 453 | #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ |
bc02af93 | 454 | |
e1319331 HS |
455 | /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ |
456 | static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) | |
9af3c2de YG |
457 | { |
458 | struct pglist_data *pgdat; | |
459 | unsigned long zones_size[MAX_NR_ZONES] = {0}; | |
460 | unsigned long zholes_size[MAX_NR_ZONES] = {0}; | |
461 | unsigned long start_pfn = start >> PAGE_SHIFT; | |
462 | ||
463 | pgdat = arch_alloc_nodedata(nid); | |
464 | if (!pgdat) | |
465 | return NULL; | |
466 | ||
467 | arch_refresh_nodedata(nid, pgdat); | |
468 | ||
469 | /* we can use NODE_DATA(nid) from here */ | |
470 | ||
471 | /* init node's zones as empty zones, we don't have any present pages.*/ | |
9109fb7b | 472 | free_area_init_node(nid, zones_size, start_pfn, zholes_size); |
9af3c2de YG |
473 | |
474 | return pgdat; | |
475 | } | |
476 | ||
477 | static void rollback_node_hotadd(int nid, pg_data_t *pgdat) | |
478 | { | |
479 | arch_refresh_nodedata(nid, NULL); | |
480 | arch_free_nodedata(pgdat); | |
481 | return; | |
482 | } | |
483 | ||
0a547039 | 484 | |
31168481 AV |
485 | /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ |
486 | int __ref add_memory(int nid, u64 start, u64 size) | |
bc02af93 | 487 | { |
9af3c2de YG |
488 | pg_data_t *pgdat = NULL; |
489 | int new_pgdat = 0; | |
ebd15302 | 490 | struct resource *res; |
bc02af93 YG |
491 | int ret; |
492 | ||
6ad696d2 AK |
493 | lock_system_sleep(); |
494 | ||
ebd15302 | 495 | res = register_memory_resource(start, size); |
6ad696d2 | 496 | ret = -EEXIST; |
ebd15302 | 497 | if (!res) |
6ad696d2 | 498 | goto out; |
ebd15302 | 499 | |
9af3c2de YG |
500 | if (!node_online(nid)) { |
501 | pgdat = hotadd_new_pgdat(nid, start); | |
6ad696d2 | 502 | ret = -ENOMEM; |
9af3c2de | 503 | if (!pgdat) |
6ad696d2 | 504 | goto out; |
9af3c2de | 505 | new_pgdat = 1; |
9af3c2de YG |
506 | } |
507 | ||
bc02af93 YG |
508 | /* call arch's memory hotadd */ |
509 | ret = arch_add_memory(nid, start, size); | |
510 | ||
9af3c2de YG |
511 | if (ret < 0) |
512 | goto error; | |
513 | ||
0fc44159 | 514 | /* we online node here. we can't roll back from here. */ |
9af3c2de YG |
515 | node_set_online(nid); |
516 | ||
0fc44159 YG |
517 | if (new_pgdat) { |
518 | ret = register_one_node(nid); | |
519 | /* | |
520 | * If sysfs file of new node can't create, cpu on the node | |
521 | * can't be hot-added. There is no rollback way now. | |
522 | * So, check by BUG_ON() to catch it reluctantly.. | |
523 | */ | |
524 | BUG_ON(ret); | |
525 | } | |
526 | ||
d96ae530 | 527 | /* create new memmap entry */ |
528 | firmware_map_add_hotplug(start, start + size, "System RAM"); | |
529 | ||
6ad696d2 AK |
530 | goto out; |
531 | ||
9af3c2de YG |
532 | error: |
533 | /* rollback pgdat allocation and others */ | |
534 | if (new_pgdat) | |
535 | rollback_node_hotadd(nid, pgdat); | |
ebd15302 KH |
536 | if (res) |
537 | release_memory_resource(res); | |
9af3c2de | 538 | |
6ad696d2 AK |
539 | out: |
540 | unlock_system_sleep(); | |
bc02af93 YG |
541 | return ret; |
542 | } | |
543 | EXPORT_SYMBOL_GPL(add_memory); | |
0c0e6195 KH |
544 | |
545 | #ifdef CONFIG_MEMORY_HOTREMOVE | |
5c755e9f BP |
546 | /* |
547 | * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy | |
548 | * set and the size of the free page is given by page_order(). Using this, | |
549 | * the function determines if the pageblock contains only free pages. | |
550 | * Due to buddy contraints, a free page at least the size of a pageblock will | |
551 | * be located at the start of the pageblock | |
552 | */ | |
553 | static inline int pageblock_free(struct page *page) | |
554 | { | |
555 | return PageBuddy(page) && page_order(page) >= pageblock_order; | |
556 | } | |
557 | ||
558 | /* Return the start of the next active pageblock after a given page */ | |
559 | static struct page *next_active_pageblock(struct page *page) | |
560 | { | |
561 | int pageblocks_stride; | |
562 | ||
563 | /* Ensure the starting page is pageblock-aligned */ | |
564 | BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1)); | |
565 | ||
566 | /* Move forward by at least 1 * pageblock_nr_pages */ | |
567 | pageblocks_stride = 1; | |
568 | ||
569 | /* If the entire pageblock is free, move to the end of free page */ | |
570 | if (pageblock_free(page)) | |
571 | pageblocks_stride += page_order(page) - pageblock_order; | |
572 | ||
573 | return page + (pageblocks_stride * pageblock_nr_pages); | |
574 | } | |
575 | ||
576 | /* Checks if this range of memory is likely to be hot-removable. */ | |
577 | int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) | |
578 | { | |
579 | int type; | |
580 | struct page *page = pfn_to_page(start_pfn); | |
581 | struct page *end_page = page + nr_pages; | |
582 | ||
583 | /* Check the starting page of each pageblock within the range */ | |
584 | for (; page < end_page; page = next_active_pageblock(page)) { | |
585 | type = get_pageblock_migratetype(page); | |
586 | ||
587 | /* | |
588 | * A pageblock containing MOVABLE or free pages is considered | |
589 | * removable | |
590 | */ | |
591 | if (type != MIGRATE_MOVABLE && !pageblock_free(page)) | |
592 | return 0; | |
593 | ||
594 | /* | |
595 | * A pageblock starting with a PageReserved page is not | |
596 | * considered removable. | |
597 | */ | |
598 | if (PageReserved(page)) | |
599 | return 0; | |
600 | } | |
601 | ||
602 | /* All pageblocks in the memory block are likely to be hot-removable */ | |
603 | return 1; | |
604 | } | |
605 | ||
0c0e6195 KH |
606 | /* |
607 | * Confirm all pages in a range [start, end) is belongs to the same zone. | |
608 | */ | |
609 | static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) | |
610 | { | |
611 | unsigned long pfn; | |
612 | struct zone *zone = NULL; | |
613 | struct page *page; | |
614 | int i; | |
615 | for (pfn = start_pfn; | |
616 | pfn < end_pfn; | |
617 | pfn += MAX_ORDER_NR_PAGES) { | |
618 | i = 0; | |
619 | /* This is just a CONFIG_HOLES_IN_ZONE check.*/ | |
620 | while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) | |
621 | i++; | |
622 | if (i == MAX_ORDER_NR_PAGES) | |
623 | continue; | |
624 | page = pfn_to_page(pfn + i); | |
625 | if (zone && page_zone(page) != zone) | |
626 | return 0; | |
627 | zone = page_zone(page); | |
628 | } | |
629 | return 1; | |
630 | } | |
631 | ||
632 | /* | |
633 | * Scanning pfn is much easier than scanning lru list. | |
634 | * Scan pfn from start to end and Find LRU page. | |
635 | */ | |
636 | int scan_lru_pages(unsigned long start, unsigned long end) | |
637 | { | |
638 | unsigned long pfn; | |
639 | struct page *page; | |
640 | for (pfn = start; pfn < end; pfn++) { | |
641 | if (pfn_valid(pfn)) { | |
642 | page = pfn_to_page(pfn); | |
643 | if (PageLRU(page)) | |
644 | return pfn; | |
645 | } | |
646 | } | |
647 | return 0; | |
648 | } | |
649 | ||
650 | static struct page * | |
3c1d4378 | 651 | hotremove_migrate_alloc(struct page *page, unsigned long private, int **x) |
0c0e6195 | 652 | { |
3c1d4378 HD |
653 | /* This should be improooooved!! */ |
654 | return alloc_page(GFP_HIGHUSER_MOVABLE); | |
0c0e6195 KH |
655 | } |
656 | ||
0c0e6195 KH |
657 | #define NR_OFFLINE_AT_ONCE_PAGES (256) |
658 | static int | |
659 | do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) | |
660 | { | |
661 | unsigned long pfn; | |
662 | struct page *page; | |
663 | int move_pages = NR_OFFLINE_AT_ONCE_PAGES; | |
664 | int not_managed = 0; | |
665 | int ret = 0; | |
666 | LIST_HEAD(source); | |
667 | ||
668 | for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) { | |
669 | if (!pfn_valid(pfn)) | |
670 | continue; | |
671 | page = pfn_to_page(pfn); | |
672 | if (!page_count(page)) | |
673 | continue; | |
674 | /* | |
675 | * We can skip free pages. And we can only deal with pages on | |
676 | * LRU. | |
677 | */ | |
62695a84 | 678 | ret = isolate_lru_page(page); |
0c0e6195 | 679 | if (!ret) { /* Success */ |
62695a84 | 680 | list_add_tail(&page->lru, &source); |
0c0e6195 | 681 | move_pages--; |
6d9c285a KM |
682 | inc_zone_page_state(page, NR_ISOLATED_ANON + |
683 | page_is_file_cache(page)); | |
684 | ||
0c0e6195 KH |
685 | } else { |
686 | /* Becasue we don't have big zone->lock. we should | |
687 | check this again here. */ | |
688 | if (page_count(page)) | |
689 | not_managed++; | |
690 | #ifdef CONFIG_DEBUG_VM | |
718a3821 WF |
691 | printk(KERN_ALERT "removing pfn %lx from LRU failed\n", |
692 | pfn); | |
693 | dump_page(page); | |
0c0e6195 KH |
694 | #endif |
695 | } | |
696 | } | |
697 | ret = -EBUSY; | |
698 | if (not_managed) { | |
699 | if (!list_empty(&source)) | |
700 | putback_lru_pages(&source); | |
701 | goto out; | |
702 | } | |
703 | ret = 0; | |
704 | if (list_empty(&source)) | |
705 | goto out; | |
706 | /* this function returns # of failed pages */ | |
62b61f61 | 707 | ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1); |
0c0e6195 KH |
708 | |
709 | out: | |
710 | return ret; | |
711 | } | |
712 | ||
713 | /* | |
714 | * remove from free_area[] and mark all as Reserved. | |
715 | */ | |
716 | static int | |
717 | offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages, | |
718 | void *data) | |
719 | { | |
720 | __offline_isolated_pages(start, start + nr_pages); | |
721 | return 0; | |
722 | } | |
723 | ||
724 | static void | |
725 | offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) | |
726 | { | |
908eedc6 | 727 | walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL, |
0c0e6195 KH |
728 | offline_isolated_pages_cb); |
729 | } | |
730 | ||
731 | /* | |
732 | * Check all pages in range, recoreded as memory resource, are isolated. | |
733 | */ | |
734 | static int | |
735 | check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages, | |
736 | void *data) | |
737 | { | |
738 | int ret; | |
739 | long offlined = *(long *)data; | |
740 | ret = test_pages_isolated(start_pfn, start_pfn + nr_pages); | |
741 | offlined = nr_pages; | |
742 | if (!ret) | |
743 | *(long *)data += offlined; | |
744 | return ret; | |
745 | } | |
746 | ||
747 | static long | |
748 | check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn) | |
749 | { | |
750 | long offlined = 0; | |
751 | int ret; | |
752 | ||
908eedc6 | 753 | ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined, |
0c0e6195 KH |
754 | check_pages_isolated_cb); |
755 | if (ret < 0) | |
756 | offlined = (long)ret; | |
757 | return offlined; | |
758 | } | |
759 | ||
b4e655a4 | 760 | static int offline_pages(unsigned long start_pfn, |
0c0e6195 KH |
761 | unsigned long end_pfn, unsigned long timeout) |
762 | { | |
763 | unsigned long pfn, nr_pages, expire; | |
764 | long offlined_pages; | |
7b78d335 | 765 | int ret, drain, retry_max, node; |
0c0e6195 | 766 | struct zone *zone; |
7b78d335 | 767 | struct memory_notify arg; |
0c0e6195 KH |
768 | |
769 | BUG_ON(start_pfn >= end_pfn); | |
770 | /* at least, alignment against pageblock is necessary */ | |
771 | if (!IS_ALIGNED(start_pfn, pageblock_nr_pages)) | |
772 | return -EINVAL; | |
773 | if (!IS_ALIGNED(end_pfn, pageblock_nr_pages)) | |
774 | return -EINVAL; | |
775 | /* This makes hotplug much easier...and readable. | |
776 | we assume this for now. .*/ | |
777 | if (!test_pages_in_a_zone(start_pfn, end_pfn)) | |
778 | return -EINVAL; | |
7b78d335 | 779 | |
6ad696d2 AK |
780 | lock_system_sleep(); |
781 | ||
7b78d335 YG |
782 | zone = page_zone(pfn_to_page(start_pfn)); |
783 | node = zone_to_nid(zone); | |
784 | nr_pages = end_pfn - start_pfn; | |
785 | ||
0c0e6195 KH |
786 | /* set above range as isolated */ |
787 | ret = start_isolate_page_range(start_pfn, end_pfn); | |
788 | if (ret) | |
6ad696d2 | 789 | goto out; |
7b78d335 YG |
790 | |
791 | arg.start_pfn = start_pfn; | |
792 | arg.nr_pages = nr_pages; | |
793 | arg.status_change_nid = -1; | |
794 | if (nr_pages >= node_present_pages(node)) | |
795 | arg.status_change_nid = node; | |
796 | ||
797 | ret = memory_notify(MEM_GOING_OFFLINE, &arg); | |
798 | ret = notifier_to_errno(ret); | |
799 | if (ret) | |
800 | goto failed_removal; | |
801 | ||
0c0e6195 KH |
802 | pfn = start_pfn; |
803 | expire = jiffies + timeout; | |
804 | drain = 0; | |
805 | retry_max = 5; | |
806 | repeat: | |
807 | /* start memory hot removal */ | |
808 | ret = -EAGAIN; | |
809 | if (time_after(jiffies, expire)) | |
810 | goto failed_removal; | |
811 | ret = -EINTR; | |
812 | if (signal_pending(current)) | |
813 | goto failed_removal; | |
814 | ret = 0; | |
815 | if (drain) { | |
816 | lru_add_drain_all(); | |
817 | flush_scheduled_work(); | |
818 | cond_resched(); | |
9f8f2172 | 819 | drain_all_pages(); |
0c0e6195 KH |
820 | } |
821 | ||
822 | pfn = scan_lru_pages(start_pfn, end_pfn); | |
823 | if (pfn) { /* We have page on LRU */ | |
824 | ret = do_migrate_range(pfn, end_pfn); | |
825 | if (!ret) { | |
826 | drain = 1; | |
827 | goto repeat; | |
828 | } else { | |
829 | if (ret < 0) | |
830 | if (--retry_max == 0) | |
831 | goto failed_removal; | |
832 | yield(); | |
833 | drain = 1; | |
834 | goto repeat; | |
835 | } | |
836 | } | |
837 | /* drain all zone's lru pagevec, this is asyncronous... */ | |
838 | lru_add_drain_all(); | |
839 | flush_scheduled_work(); | |
840 | yield(); | |
841 | /* drain pcp pages , this is synchrouns. */ | |
9f8f2172 | 842 | drain_all_pages(); |
0c0e6195 KH |
843 | /* check again */ |
844 | offlined_pages = check_pages_isolated(start_pfn, end_pfn); | |
845 | if (offlined_pages < 0) { | |
846 | ret = -EBUSY; | |
847 | goto failed_removal; | |
848 | } | |
849 | printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages); | |
850 | /* Ok, all of our target is islaoted. | |
851 | We cannot do rollback at this point. */ | |
852 | offline_isolated_pages(start_pfn, end_pfn); | |
dbc0e4ce KH |
853 | /* reset pagetype flags and makes migrate type to be MOVABLE */ |
854 | undo_isolate_page_range(start_pfn, end_pfn); | |
0c0e6195 | 855 | /* removal success */ |
0c0e6195 KH |
856 | zone->present_pages -= offlined_pages; |
857 | zone->zone_pgdat->node_present_pages -= offlined_pages; | |
858 | totalram_pages -= offlined_pages; | |
7b78d335 | 859 | |
bce7394a MK |
860 | setup_per_zone_wmarks(); |
861 | calculate_zone_inactive_ratio(zone); | |
8fe23e05 DR |
862 | if (!node_present_pages(node)) { |
863 | node_clear_state(node, N_HIGH_MEMORY); | |
864 | kswapd_stop(node); | |
865 | } | |
bce7394a | 866 | |
0c0e6195 KH |
867 | vm_total_pages = nr_free_pagecache_pages(); |
868 | writeback_set_ratelimit(); | |
7b78d335 YG |
869 | |
870 | memory_notify(MEM_OFFLINE, &arg); | |
6ad696d2 | 871 | unlock_system_sleep(); |
0c0e6195 KH |
872 | return 0; |
873 | ||
874 | failed_removal: | |
875 | printk(KERN_INFO "memory offlining %lx to %lx failed\n", | |
876 | start_pfn, end_pfn); | |
7b78d335 | 877 | memory_notify(MEM_CANCEL_OFFLINE, &arg); |
0c0e6195 KH |
878 | /* pushback to free area */ |
879 | undo_isolate_page_range(start_pfn, end_pfn); | |
7b78d335 | 880 | |
6ad696d2 AK |
881 | out: |
882 | unlock_system_sleep(); | |
0c0e6195 KH |
883 | return ret; |
884 | } | |
71088785 BP |
885 | |
886 | int remove_memory(u64 start, u64 size) | |
887 | { | |
888 | unsigned long start_pfn, end_pfn; | |
889 | ||
890 | start_pfn = PFN_DOWN(start); | |
891 | end_pfn = start_pfn + PFN_DOWN(size); | |
892 | return offline_pages(start_pfn, end_pfn, 120 * HZ); | |
893 | } | |
48e94196 KH |
894 | #else |
895 | int remove_memory(u64 start, u64 size) | |
896 | { | |
897 | return -EINVAL; | |
898 | } | |
0c0e6195 | 899 | #endif /* CONFIG_MEMORY_HOTREMOVE */ |
71088785 | 900 | EXPORT_SYMBOL_GPL(remove_memory); |