2 * linux/mm/memory_hotplug.c
7 #include <linux/stddef.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/export.h>
15 #include <linux/pagevec.h>
16 #include <linux/writeback.h>
17 #include <linux/slab.h>
18 #include <linux/sysctl.h>
19 #include <linux/cpu.h>
20 #include <linux/memory.h>
21 #include <linux/memory_hotplug.h>
22 #include <linux/highmem.h>
23 #include <linux/vmalloc.h>
24 #include <linux/ioport.h>
25 #include <linux/delay.h>
26 #include <linux/migrate.h>
27 #include <linux/page-isolation.h>
28 #include <linux/pfn.h>
29 #include <linux/suspend.h>
30 #include <linux/mm_inline.h>
31 #include <linux/firmware-map.h>
33 #include <asm/tlbflush.h>
38 * online_page_callback contains pointer to current page onlining function.
39 * Initially it is generic_online_page(). If it is required it could be
40 * changed by calling set_online_page_callback() for callback registration
41 * and restore_online_page_callback() for generic callback restore.
44 static void generic_online_page(struct page *page);
46 static online_page_callback_t online_page_callback = generic_online_page;
48 DEFINE_MUTEX(mem_hotplug_mutex);
50 void lock_memory_hotplug(void)
52 mutex_lock(&mem_hotplug_mutex);
54 /* for exclusive hibernation if CONFIG_HIBERNATION=y */
58 void unlock_memory_hotplug(void)
60 unlock_system_sleep();
61 mutex_unlock(&mem_hotplug_mutex);
65 /* add this memory to iomem resource */
66 static struct resource *register_memory_resource(u64 start, u64 size)
69 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
72 res->name = "System RAM";
74 res->end = start + size - 1;
75 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
76 if (request_resource(&iomem_resource, res) < 0) {
77 printk("System RAM resource %llx - %llx cannot be added\n",
78 (unsigned long long)res->start, (unsigned long long)res->end);
85 static void release_memory_resource(struct resource *res)
89 release_resource(res);
94 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
95 #ifndef CONFIG_SPARSEMEM_VMEMMAP
96 static void get_page_bootmem(unsigned long info, struct page *page,
99 page->lru.next = (struct list_head *) type;
100 SetPagePrivate(page);
101 set_page_private(page, info);
102 atomic_inc(&page->_count);
105 /* reference to __meminit __free_pages_bootmem is valid
106 * so use __ref to tell modpost not to generate a warning */
107 void __ref put_page_bootmem(struct page *page)
111 type = (unsigned long) page->lru.next;
112 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
113 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
115 if (atomic_dec_return(&page->_count) == 1) {
116 ClearPagePrivate(page);
117 set_page_private(page, 0);
118 INIT_LIST_HEAD(&page->lru);
119 __free_pages_bootmem(page, 0);
124 static void register_page_bootmem_info_section(unsigned long start_pfn)
126 unsigned long *usemap, mapsize, section_nr, i;
127 struct mem_section *ms;
128 struct page *page, *memmap;
130 section_nr = pfn_to_section_nr(start_pfn);
131 ms = __nr_to_section(section_nr);
133 /* Get section's memmap address */
134 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
137 * Get page for the memmap's phys address
138 * XXX: need more consideration for sparse_vmemmap...
140 page = virt_to_page(memmap);
141 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
142 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
144 /* remember memmap's page */
145 for (i = 0; i < mapsize; i++, page++)
146 get_page_bootmem(section_nr, page, SECTION_INFO);
148 usemap = __nr_to_section(section_nr)->pageblock_flags;
149 page = virt_to_page(usemap);
151 mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
153 for (i = 0; i < mapsize; i++, page++)
154 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
158 void register_page_bootmem_info_node(struct pglist_data *pgdat)
160 unsigned long i, pfn, end_pfn, nr_pages;
161 int node = pgdat->node_id;
165 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
166 page = virt_to_page(pgdat);
168 for (i = 0; i < nr_pages; i++, page++)
169 get_page_bootmem(node, page, NODE_INFO);
171 zone = &pgdat->node_zones[0];
172 for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
173 if (zone->wait_table) {
174 nr_pages = zone->wait_table_hash_nr_entries
175 * sizeof(wait_queue_head_t);
176 nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
177 page = virt_to_page(zone->wait_table);
179 for (i = 0; i < nr_pages; i++, page++)
180 get_page_bootmem(node, page, NODE_INFO);
184 pfn = pgdat->node_start_pfn;
185 end_pfn = pfn + pgdat->node_spanned_pages;
187 /* register_section info */
188 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
190 * Some platforms can assign the same pfn to multiple nodes - on
191 * node0 as well as nodeN. To avoid registering a pfn against
192 * multiple nodes we check that this pfn does not already
193 * reside in some other node.
195 if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node))
196 register_page_bootmem_info_section(pfn);
199 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
201 static void grow_zone_span(struct zone *zone, unsigned long start_pfn,
202 unsigned long end_pfn)
204 unsigned long old_zone_end_pfn;
206 zone_span_writelock(zone);
208 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
209 if (start_pfn < zone->zone_start_pfn)
210 zone->zone_start_pfn = start_pfn;
212 zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
213 zone->zone_start_pfn;
215 zone_span_writeunlock(zone);
218 static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
219 unsigned long end_pfn)
221 unsigned long old_pgdat_end_pfn =
222 pgdat->node_start_pfn + pgdat->node_spanned_pages;
224 if (start_pfn < pgdat->node_start_pfn)
225 pgdat->node_start_pfn = start_pfn;
227 pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
228 pgdat->node_start_pfn;
231 static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn)
233 struct pglist_data *pgdat = zone->zone_pgdat;
234 int nr_pages = PAGES_PER_SECTION;
235 int nid = pgdat->node_id;
239 zone_type = zone - pgdat->node_zones;
240 if (!zone->wait_table) {
243 ret = init_currently_empty_zone(zone, phys_start_pfn,
244 nr_pages, MEMMAP_HOTPLUG);
248 pgdat_resize_lock(zone->zone_pgdat, &flags);
249 grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
250 grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
251 phys_start_pfn + nr_pages);
252 pgdat_resize_unlock(zone->zone_pgdat, &flags);
253 memmap_init_zone(nr_pages, nid, zone_type,
254 phys_start_pfn, MEMMAP_HOTPLUG);
258 static int __meminit __add_section(int nid, struct zone *zone,
259 unsigned long phys_start_pfn)
261 int nr_pages = PAGES_PER_SECTION;
264 if (pfn_valid(phys_start_pfn))
267 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
272 ret = __add_zone(zone, phys_start_pfn);
277 return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
280 #ifdef CONFIG_SPARSEMEM_VMEMMAP
281 static int __remove_section(struct zone *zone, struct mem_section *ms)
284 * XXX: Freeing memmap with vmemmap is not implement yet.
285 * This should be removed later.
290 static int __remove_section(struct zone *zone, struct mem_section *ms)
293 struct pglist_data *pgdat = zone->zone_pgdat;
296 if (!valid_section(ms))
299 ret = unregister_memory_section(ms);
303 pgdat_resize_lock(pgdat, &flags);
304 sparse_remove_one_section(zone, ms);
305 pgdat_resize_unlock(pgdat, &flags);
311 * Reasonably generic function for adding memory. It is
312 * expected that archs that support memory hotplug will
313 * call this function after deciding the zone to which to
316 int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
317 unsigned long nr_pages)
321 int start_sec, end_sec;
322 /* during initialize mem_map, align hot-added range to section */
323 start_sec = pfn_to_section_nr(phys_start_pfn);
324 end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
326 for (i = start_sec; i <= end_sec; i++) {
327 err = __add_section(nid, zone, i << PFN_SECTION_SHIFT);
330 * EEXIST is finally dealt with by ioresource collision
331 * check. see add_memory() => register_memory_resource()
332 * Warning will be printed if there is collision.
334 if (err && (err != -EEXIST))
341 EXPORT_SYMBOL_GPL(__add_pages);
344 * __remove_pages() - remove sections of pages from a zone
345 * @zone: zone from which pages need to be removed
346 * @phys_start_pfn: starting pageframe (must be aligned to start of a section)
347 * @nr_pages: number of pages to remove (must be multiple of section size)
349 * Generic helper function to remove section mappings and sysfs entries
350 * for the section of the memory we are removing. Caller needs to make
351 * sure that pages are marked reserved and zones are adjust properly by
352 * calling offline_pages().
354 int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
355 unsigned long nr_pages)
357 unsigned long i, ret = 0;
358 int sections_to_remove;
361 * We can only remove entire sections
363 BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
364 BUG_ON(nr_pages % PAGES_PER_SECTION);
366 sections_to_remove = nr_pages / PAGES_PER_SECTION;
367 for (i = 0; i < sections_to_remove; i++) {
368 unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
369 release_mem_region(pfn << PAGE_SHIFT,
370 PAGES_PER_SECTION << PAGE_SHIFT);
371 ret = __remove_section(zone, __pfn_to_section(pfn));
377 EXPORT_SYMBOL_GPL(__remove_pages);
379 int set_online_page_callback(online_page_callback_t callback)
383 lock_memory_hotplug();
385 if (online_page_callback == generic_online_page) {
386 online_page_callback = callback;
390 unlock_memory_hotplug();
394 EXPORT_SYMBOL_GPL(set_online_page_callback);
396 int restore_online_page_callback(online_page_callback_t callback)
400 lock_memory_hotplug();
402 if (online_page_callback == callback) {
403 online_page_callback = generic_online_page;
407 unlock_memory_hotplug();
411 EXPORT_SYMBOL_GPL(restore_online_page_callback);
413 void __online_page_set_limits(struct page *page)
415 unsigned long pfn = page_to_pfn(page);
417 if (pfn >= num_physpages)
418 num_physpages = pfn + 1;
420 EXPORT_SYMBOL_GPL(__online_page_set_limits);
422 void __online_page_increment_counters(struct page *page)
426 #ifdef CONFIG_HIGHMEM
427 if (PageHighMem(page))
431 EXPORT_SYMBOL_GPL(__online_page_increment_counters);
433 void __online_page_free(struct page *page)
435 ClearPageReserved(page);
436 init_page_count(page);
439 EXPORT_SYMBOL_GPL(__online_page_free);
441 static void generic_online_page(struct page *page)
443 __online_page_set_limits(page);
444 __online_page_increment_counters(page);
445 __online_page_free(page);
448 static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
452 unsigned long onlined_pages = *(unsigned long *)arg;
454 if (PageReserved(pfn_to_page(start_pfn)))
455 for (i = 0; i < nr_pages; i++) {
456 page = pfn_to_page(start_pfn + i);
457 (*online_page_callback)(page);
460 *(unsigned long *)arg = onlined_pages;
465 int __ref online_pages(unsigned long pfn, unsigned long nr_pages)
467 unsigned long onlined_pages = 0;
469 int need_zonelists_rebuild = 0;
472 struct memory_notify arg;
474 lock_memory_hotplug();
476 arg.nr_pages = nr_pages;
477 arg.status_change_nid = -1;
479 nid = page_to_nid(pfn_to_page(pfn));
480 if (node_present_pages(nid) == 0)
481 arg.status_change_nid = nid;
483 ret = memory_notify(MEM_GOING_ONLINE, &arg);
484 ret = notifier_to_errno(ret);
486 memory_notify(MEM_CANCEL_ONLINE, &arg);
487 unlock_memory_hotplug();
491 * This doesn't need a lock to do pfn_to_page().
492 * The section can't be removed here because of the
493 * memory_block->state_mutex.
495 zone = page_zone(pfn_to_page(pfn));
497 * If this zone is not populated, then it is not in zonelist.
498 * This means the page allocator ignores this zone.
499 * So, zonelist must be updated after online.
501 mutex_lock(&zonelists_mutex);
502 if (!populated_zone(zone))
503 need_zonelists_rebuild = 1;
505 ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
508 mutex_unlock(&zonelists_mutex);
509 printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
511 memory_notify(MEM_CANCEL_ONLINE, &arg);
512 unlock_memory_hotplug();
516 zone->present_pages += onlined_pages;
517 zone->zone_pgdat->node_present_pages += onlined_pages;
519 node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
520 if (need_zonelists_rebuild)
521 build_all_zonelists(zone);
523 zone_pcp_update(zone);
526 mutex_unlock(&zonelists_mutex);
528 init_per_zone_wmark_min();
531 kswapd_run(zone_to_nid(zone));
533 vm_total_pages = nr_free_pagecache_pages();
535 writeback_set_ratelimit();
538 memory_notify(MEM_ONLINE, &arg);
539 unlock_memory_hotplug();
543 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
545 /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
546 static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
548 struct pglist_data *pgdat;
549 unsigned long zones_size[MAX_NR_ZONES] = {0};
550 unsigned long zholes_size[MAX_NR_ZONES] = {0};
551 unsigned long start_pfn = start >> PAGE_SHIFT;
553 pgdat = arch_alloc_nodedata(nid);
557 arch_refresh_nodedata(nid, pgdat);
559 /* we can use NODE_DATA(nid) from here */
561 /* init node's zones as empty zones, we don't have any present pages.*/
562 free_area_init_node(nid, zones_size, start_pfn, zholes_size);
565 * The node we allocated has no zone fallback lists. For avoiding
566 * to access not-initialized zonelist, build here.
568 mutex_lock(&zonelists_mutex);
569 build_all_zonelists(NULL);
570 mutex_unlock(&zonelists_mutex);
575 static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
577 arch_refresh_nodedata(nid, NULL);
578 arch_free_nodedata(pgdat);
584 * called by cpu_up() to online a node without onlined memory.
586 int mem_online_node(int nid)
591 lock_memory_hotplug();
592 pgdat = hotadd_new_pgdat(nid, 0);
597 node_set_online(nid);
598 ret = register_one_node(nid);
602 unlock_memory_hotplug();
606 /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
607 int __ref add_memory(int nid, u64 start, u64 size)
609 pg_data_t *pgdat = NULL;
611 struct resource *res;
614 lock_memory_hotplug();
616 res = register_memory_resource(start, size);
621 if (!node_online(nid)) {
622 pgdat = hotadd_new_pgdat(nid, start);
629 /* call arch's memory hotadd */
630 ret = arch_add_memory(nid, start, size);
635 /* we online node here. we can't roll back from here. */
636 node_set_online(nid);
639 ret = register_one_node(nid);
641 * If sysfs file of new node can't create, cpu on the node
642 * can't be hot-added. There is no rollback way now.
643 * So, check by BUG_ON() to catch it reluctantly..
648 /* create new memmap entry */
649 firmware_map_add_hotplug(start, start + size, "System RAM");
654 /* rollback pgdat allocation and others */
656 rollback_node_hotadd(nid, pgdat);
658 release_memory_resource(res);
661 unlock_memory_hotplug();
664 EXPORT_SYMBOL_GPL(add_memory);
666 #ifdef CONFIG_MEMORY_HOTREMOVE
668 * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
669 * set and the size of the free page is given by page_order(). Using this,
670 * the function determines if the pageblock contains only free pages.
671 * Due to buddy contraints, a free page at least the size of a pageblock will
672 * be located at the start of the pageblock
674 static inline int pageblock_free(struct page *page)
676 return PageBuddy(page) && page_order(page) >= pageblock_order;
679 /* Return the start of the next active pageblock after a given page */
680 static struct page *next_active_pageblock(struct page *page)
682 /* Ensure the starting page is pageblock-aligned */
683 BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
685 /* If the entire pageblock is free, move to the end of free page */
686 if (pageblock_free(page)) {
688 /* be careful. we don't have locks, page_order can be changed.*/
689 order = page_order(page);
690 if ((order < MAX_ORDER) && (order >= pageblock_order))
691 return page + (1 << order);
694 return page + pageblock_nr_pages;
697 /* Checks if this range of memory is likely to be hot-removable. */
698 int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
700 struct page *page = pfn_to_page(start_pfn);
701 struct page *end_page = page + nr_pages;
703 /* Check the starting page of each pageblock within the range */
704 for (; page < end_page; page = next_active_pageblock(page)) {
705 if (!is_pageblock_removable_nolock(page))
710 /* All pageblocks in the memory block are likely to be hot-removable */
715 * Confirm all pages in a range [start, end) is belongs to the same zone.
717 static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
719 unsigned long pfn, sec_end_pfn;
720 struct zone *zone = NULL;
723 for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn);
725 pfn = sec_end_pfn + 1, sec_end_pfn += PAGES_PER_SECTION) {
726 /* Make sure the memory section is present first */
727 if (!present_section_nr(pfn_to_section_nr(pfn)))
729 for (; pfn < sec_end_pfn && pfn < end_pfn;
730 pfn += MAX_ORDER_NR_PAGES) {
732 /* This is just a CONFIG_HOLES_IN_ZONE check.*/
733 while ((i < MAX_ORDER_NR_PAGES) &&
734 !pfn_valid_within(pfn + i))
736 if (i == MAX_ORDER_NR_PAGES)
738 page = pfn_to_page(pfn + i);
739 if (zone && page_zone(page) != zone)
741 zone = page_zone(page);
748 * Scanning pfn is much easier than scanning lru list.
749 * Scan pfn from start to end and Find LRU page.
751 static unsigned long scan_lru_pages(unsigned long start, unsigned long end)
755 for (pfn = start; pfn < end; pfn++) {
756 if (pfn_valid(pfn)) {
757 page = pfn_to_page(pfn);
766 hotremove_migrate_alloc(struct page *page, unsigned long private, int **x)
768 /* This should be improooooved!! */
769 return alloc_page(GFP_HIGHUSER_MOVABLE);
772 #define NR_OFFLINE_AT_ONCE_PAGES (256)
774 do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
778 int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
783 for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
786 page = pfn_to_page(pfn);
787 if (!get_page_unless_zero(page))
790 * We can skip free pages. And we can only deal with pages on
793 ret = isolate_lru_page(page);
794 if (!ret) { /* Success */
796 list_add_tail(&page->lru, &source);
798 inc_zone_page_state(page, NR_ISOLATED_ANON +
799 page_is_file_cache(page));
802 #ifdef CONFIG_DEBUG_VM
803 printk(KERN_ALERT "removing pfn %lx from LRU failed\n",
808 /* Because we don't have big zone->lock. we should
809 check this again here. */
810 if (page_count(page)) {
817 if (!list_empty(&source)) {
819 putback_lru_pages(&source);
822 /* this function returns # of failed pages */
823 ret = migrate_pages(&source, hotremove_migrate_alloc, 0,
826 putback_lru_pages(&source);
833 * remove from free_area[] and mark all as Reserved.
836 offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
839 __offline_isolated_pages(start, start + nr_pages);
844 offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
846 walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
847 offline_isolated_pages_cb);
851 * Check all pages in range, recoreded as memory resource, are isolated.
854 check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
858 long offlined = *(long *)data;
859 ret = test_pages_isolated(start_pfn, start_pfn + nr_pages);
862 *(long *)data += offlined;
867 check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
872 ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
873 check_pages_isolated_cb);
875 offlined = (long)ret;
879 static int __ref offline_pages(unsigned long start_pfn,
880 unsigned long end_pfn, unsigned long timeout)
882 unsigned long pfn, nr_pages, expire;
884 int ret, drain, retry_max, node;
886 struct memory_notify arg;
888 BUG_ON(start_pfn >= end_pfn);
889 /* at least, alignment against pageblock is necessary */
890 if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
892 if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
894 /* This makes hotplug much easier...and readable.
895 we assume this for now. .*/
896 if (!test_pages_in_a_zone(start_pfn, end_pfn))
899 lock_memory_hotplug();
901 zone = page_zone(pfn_to_page(start_pfn));
902 node = zone_to_nid(zone);
903 nr_pages = end_pfn - start_pfn;
905 /* set above range as isolated */
906 ret = start_isolate_page_range(start_pfn, end_pfn);
910 arg.start_pfn = start_pfn;
911 arg.nr_pages = nr_pages;
912 arg.status_change_nid = -1;
913 if (nr_pages >= node_present_pages(node))
914 arg.status_change_nid = node;
916 ret = memory_notify(MEM_GOING_OFFLINE, &arg);
917 ret = notifier_to_errno(ret);
922 expire = jiffies + timeout;
926 /* start memory hot removal */
928 if (time_after(jiffies, expire))
931 if (signal_pending(current))
940 pfn = scan_lru_pages(start_pfn, end_pfn);
941 if (pfn) { /* We have page on LRU */
942 ret = do_migrate_range(pfn, end_pfn);
948 if (--retry_max == 0)
955 /* drain all zone's lru pagevec, this is asyncronous... */
958 /* drain pcp pages , this is synchrouns. */
961 offlined_pages = check_pages_isolated(start_pfn, end_pfn);
962 if (offlined_pages < 0) {
966 printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
967 /* Ok, all of our target is islaoted.
968 We cannot do rollback at this point. */
969 offline_isolated_pages(start_pfn, end_pfn);
970 /* reset pagetype flags and makes migrate type to be MOVABLE */
971 undo_isolate_page_range(start_pfn, end_pfn);
972 /* removal success */
973 zone->present_pages -= offlined_pages;
974 zone->zone_pgdat->node_present_pages -= offlined_pages;
975 totalram_pages -= offlined_pages;
977 init_per_zone_wmark_min();
979 if (!node_present_pages(node)) {
980 node_clear_state(node, N_HIGH_MEMORY);
984 vm_total_pages = nr_free_pagecache_pages();
985 writeback_set_ratelimit();
987 memory_notify(MEM_OFFLINE, &arg);
988 unlock_memory_hotplug();
992 printk(KERN_INFO "memory offlining %lx to %lx failed\n",
994 memory_notify(MEM_CANCEL_OFFLINE, &arg);
995 /* pushback to free area */
996 undo_isolate_page_range(start_pfn, end_pfn);
999 unlock_memory_hotplug();
1003 int remove_memory(u64 start, u64 size)
1005 unsigned long start_pfn, end_pfn;
1007 start_pfn = PFN_DOWN(start);
1008 end_pfn = start_pfn + PFN_DOWN(size);
1009 return offline_pages(start_pfn, end_pfn, 120 * HZ);
1012 int remove_memory(u64 start, u64 size)
1016 #endif /* CONFIG_MEMORY_HOTREMOVE */
1017 EXPORT_SYMBOL_GPL(remove_memory);