| /* |
| * linux/mm/memory_hotplug.c |
| * |
| * Copyright (C) |
| */ |
| |
| #include <linux/stddef.h> |
| #include <linux/mm.h> |
| #include <linux/sched/signal.h> |
| #include <linux/swap.h> |
| #include <linux/interrupt.h> |
| #include <linux/pagemap.h> |
| #include <linux/compiler.h> |
| #include <linux/export.h> |
| #include <linux/pagevec.h> |
| #include <linux/writeback.h> |
| #include <linux/slab.h> |
| #include <linux/sysctl.h> |
| #include <linux/cpu.h> |
| #include <linux/memory.h> |
| #include <linux/memremap.h> |
| #include <linux/memory_hotplug.h> |
| #include <linux/highmem.h> |
| #include <linux/vmalloc.h> |
| #include <linux/ioport.h> |
| #include <linux/delay.h> |
| #include <linux/migrate.h> |
| #include <linux/page-isolation.h> |
| #include <linux/pfn.h> |
| #include <linux/suspend.h> |
| #include <linux/mm_inline.h> |
| #include <linux/firmware-map.h> |
| #include <linux/stop_machine.h> |
| #include <linux/hugetlb.h> |
| #include <linux/memblock.h> |
| #include <linux/compaction.h> |
| |
| #include <asm/tlbflush.h> |
| |
| #include "internal.h" |
| |
| /* |
| * online_page_callback contains pointer to current page onlining function. |
| * Initially it is generic_online_page(). If it is required it could be |
| * changed by calling set_online_page_callback() for callback registration |
| * and restore_online_page_callback() for generic callback restore. |
| */ |
| |
| static void generic_online_page(struct page *page); |
| |
| static online_page_callback_t online_page_callback = generic_online_page; |
| static DEFINE_MUTEX(online_page_callback_lock); |
| |
| DEFINE_STATIC_PERCPU_RWSEM(mem_hotplug_lock); |
| |
| void get_online_mems(void) |
| { |
| percpu_down_read(&mem_hotplug_lock); |
| } |
| |
| void put_online_mems(void) |
| { |
| percpu_up_read(&mem_hotplug_lock); |
| } |
| |
| bool movable_node_enabled = false; |
| |
| #ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE |
| bool memhp_auto_online; |
| #else |
| bool memhp_auto_online = true; |
| #endif |
| EXPORT_SYMBOL_GPL(memhp_auto_online); |
| |
| static int __init setup_memhp_default_state(char *str) |
| { |
| if (!strcmp(str, "online")) |
| memhp_auto_online = true; |
| else if (!strcmp(str, "offline")) |
| memhp_auto_online = false; |
| |
| return 1; |
| } |
| __setup("memhp_default_state=", setup_memhp_default_state); |
| |
| void mem_hotplug_begin(void) |
| { |
| cpus_read_lock(); |
| percpu_down_write(&mem_hotplug_lock); |
| } |
| |
| void mem_hotplug_done(void) |
| { |
| percpu_up_write(&mem_hotplug_lock); |
| cpus_read_unlock(); |
| } |
| |
| /* add this memory to iomem resource */ |
| static struct resource *register_memory_resource(u64 start, u64 size) |
| { |
| struct resource *res, *conflict; |
| res = kzalloc(sizeof(struct resource), GFP_KERNEL); |
| if (!res) |
| return ERR_PTR(-ENOMEM); |
| |
| res->name = "System RAM"; |
| res->start = start; |
| res->end = start + size - 1; |
| res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; |
| conflict = request_resource_conflict(&iomem_resource, res); |
| if (conflict) { |
| if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) { |
| pr_debug("Device unaddressable memory block " |
| "memory hotplug at %#010llx !\n", |
| (unsigned long long)start); |
| } |
| pr_debug("System RAM resource %pR cannot be added\n", res); |
| kfree(res); |
| return ERR_PTR(-EEXIST); |
| } |
| return res; |
| } |
| |
| static void release_memory_resource(struct resource *res) |
| { |
| if (!res) |
| return; |
| release_resource(res); |
| kfree(res); |
| return; |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE |
| void get_page_bootmem(unsigned long info, struct page *page, |
| unsigned long type) |
| { |
| page->freelist = (void *)type; |
| SetPagePrivate(page); |
| set_page_private(page, info); |
| page_ref_inc(page); |
| } |
| |
| void put_page_bootmem(struct page *page) |
| { |
| unsigned long type; |
| |
| type = (unsigned long) page->freelist; |
| BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || |
| type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE); |
| |
| if (page_ref_dec_return(page) == 1) { |
| page->freelist = NULL; |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| INIT_LIST_HEAD(&page->lru); |
| free_reserved_page(page); |
| } |
| } |
| |
| #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE |
| #ifndef CONFIG_SPARSEMEM_VMEMMAP |
| static void register_page_bootmem_info_section(unsigned long start_pfn) |
| { |
| unsigned long *usemap, mapsize, section_nr, i; |
| struct mem_section *ms; |
| struct page *page, *memmap; |
| |
| section_nr = pfn_to_section_nr(start_pfn); |
| ms = __nr_to_section(section_nr); |
| |
| /* Get section's memmap address */ |
| memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); |
| |
| /* |
| * Get page for the memmap's phys address |
| * XXX: need more consideration for sparse_vmemmap... |
| */ |
| page = virt_to_page(memmap); |
| mapsize = sizeof(struct page) * PAGES_PER_SECTION; |
| mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT; |
| |
| /* remember memmap's page */ |
| for (i = 0; i < mapsize; i++, page++) |
| get_page_bootmem(section_nr, page, SECTION_INFO); |
| |
| usemap = ms->pageblock_flags; |
| page = virt_to_page(usemap); |
| |
| mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT; |
| |
| for (i = 0; i < mapsize; i++, page++) |
| get_page_bootmem(section_nr, page, MIX_SECTION_INFO); |
| |
| } |
| #else /* CONFIG_SPARSEMEM_VMEMMAP */ |
| static void register_page_bootmem_info_section(unsigned long start_pfn) |
| { |
| unsigned long *usemap, mapsize, section_nr, i; |
| struct mem_section *ms; |
| struct page *page, *memmap; |
| |
| section_nr = pfn_to_section_nr(start_pfn); |
| ms = __nr_to_section(section_nr); |
| |
| memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); |
| |
| register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION); |
| |
| usemap = ms->pageblock_flags; |
| page = virt_to_page(usemap); |
| |
| mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT; |
| |
| for (i = 0; i < mapsize; i++, page++) |
| get_page_bootmem(section_nr, page, MIX_SECTION_INFO); |
| } |
| #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ |
| |
| void __init register_page_bootmem_info_node(struct pglist_data *pgdat) |
| { |
| unsigned long i, pfn, end_pfn, nr_pages; |
| int node = pgdat->node_id; |
| struct page *page; |
| |
| nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT; |
| page = virt_to_page(pgdat); |
| |
| for (i = 0; i < nr_pages; i++, page++) |
| get_page_bootmem(node, page, NODE_INFO); |
| |
| pfn = pgdat->node_start_pfn; |
| end_pfn = pgdat_end_pfn(pgdat); |
| |
| /* register section info */ |
| for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) { |
| /* |
| * Some platforms can assign the same pfn to multiple nodes - on |
| * node0 as well as nodeN. To avoid registering a pfn against |
| * multiple nodes we check that this pfn does not already |
| * reside in some other nodes. |
| */ |
| if (pfn_valid(pfn) && (early_pfn_to_nid(pfn) == node)) |
| register_page_bootmem_info_section(pfn); |
| } |
| } |
| #endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */ |
| |
| static int __meminit __add_section(int nid, unsigned long phys_start_pfn, |
| struct vmem_altmap *altmap, bool want_memblock) |
| { |
| int ret; |
| |
| if (pfn_valid(phys_start_pfn)) |
| return -EEXIST; |
| |
| ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn, altmap); |
| if (ret < 0) |
| return ret; |
| |
| if (!want_memblock) |
| return 0; |
| |
| return hotplug_memory_register(nid, __pfn_to_section(phys_start_pfn)); |
| } |
| |
| /* |
| * Reasonably generic function for adding memory. It is |
| * expected that archs that support memory hotplug will |
| * call this function after deciding the zone to which to |
| * add the new pages. |
| */ |
| int __ref __add_pages(int nid, unsigned long phys_start_pfn, |
| unsigned long nr_pages, struct vmem_altmap *altmap, |
| bool want_memblock) |
| { |
| unsigned long i; |
| int err = 0; |
| int start_sec, end_sec; |
| |
| /* during initialize mem_map, align hot-added range to section */ |
| start_sec = pfn_to_section_nr(phys_start_pfn); |
| end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1); |
| |
| if (altmap) { |
| /* |
| * Validate altmap is within bounds of the total request |
| */ |
| if (altmap->base_pfn != phys_start_pfn |
| || vmem_altmap_offset(altmap) > nr_pages) { |
| pr_warn_once("memory add fail, invalid altmap\n"); |
| err = -EINVAL; |
| goto out; |
| } |
| altmap->alloc = 0; |
| } |
| |
| for (i = start_sec; i <= end_sec; i++) { |
| err = __add_section(nid, section_nr_to_pfn(i), altmap, |
| want_memblock); |
| |
| /* |
| * EEXIST is finally dealt with by ioresource collision |
| * check. see add_memory() => register_memory_resource() |
| * Warning will be printed if there is collision. |
| */ |
| if (err && (err != -EEXIST)) |
| break; |
| err = 0; |
| cond_resched(); |
| } |
| vmemmap_populate_print_last(); |
| out: |
| return err; |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| /* find the smallest valid pfn in the range [start_pfn, end_pfn) */ |
| static unsigned long find_smallest_section_pfn(int nid, struct zone *zone, |
| unsigned long start_pfn, |
| unsigned long end_pfn) |
| { |
| struct mem_section *ms; |
| |
| for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) { |
| ms = __pfn_to_section(start_pfn); |
| |
| if (unlikely(!valid_section(ms))) |
| continue; |
| |
| if (unlikely(pfn_to_nid(start_pfn) != nid)) |
| continue; |
| |
| if (zone && zone != page_zone(pfn_to_page(start_pfn))) |
| continue; |
| |
| return start_pfn; |
| } |
| |
| return 0; |
| } |
| |
| /* find the biggest valid pfn in the range [start_pfn, end_pfn). */ |
| static unsigned long find_biggest_section_pfn(int nid, struct zone *zone, |
| unsigned long start_pfn, |
| unsigned long end_pfn) |
| { |
| struct mem_section *ms; |
| unsigned long pfn; |
| |
| /* pfn is the end pfn of a memory section. */ |
| pfn = end_pfn - 1; |
| for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) { |
| ms = __pfn_to_section(pfn); |
| |
| if (unlikely(!valid_section(ms))) |
| continue; |
| |
| if (unlikely(pfn_to_nid(pfn) != nid)) |
| continue; |
| |
| if (zone && zone != page_zone(pfn_to_page(pfn))) |
| continue; |
| |
| return pfn; |
| } |
| |
| return 0; |
| } |
| |
| static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, |
| unsigned long end_pfn) |
| { |
| unsigned long zone_start_pfn = zone->zone_start_pfn; |
| unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */ |
| unsigned long zone_end_pfn = z; |
| unsigned long pfn; |
| struct mem_section *ms; |
| int nid = zone_to_nid(zone); |
| |
| zone_span_writelock(zone); |
| if (zone_start_pfn == start_pfn) { |
| /* |
| * If the section is smallest section in the zone, it need |
| * shrink zone->zone_start_pfn and zone->zone_spanned_pages. |
| * In this case, we find second smallest valid mem_section |
| * for shrinking zone. |
| */ |
| pfn = find_smallest_section_pfn(nid, zone, end_pfn, |
| zone_end_pfn); |
| if (pfn) { |
| zone->zone_start_pfn = pfn; |
| zone->spanned_pages = zone_end_pfn - pfn; |
| } |
| } else if (zone_end_pfn == end_pfn) { |
| /* |
| * If the section is biggest section in the zone, it need |
| * shrink zone->spanned_pages. |
| * In this case, we find second biggest valid mem_section for |
| * shrinking zone. |
| */ |
| pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn, |
| start_pfn); |
| if (pfn) |
| zone->spanned_pages = pfn - zone_start_pfn + 1; |
| } |
| |
| /* |
| * The section is not biggest or smallest mem_section in the zone, it |
| * only creates a hole in the zone. So in this case, we need not |
| * change the zone. But perhaps, the zone has only hole data. Thus |
| * it check the zone has only hole or not. |
| */ |
| pfn = zone_start_pfn; |
| for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) { |
| ms = __pfn_to_section(pfn); |
| |
| if (unlikely(!valid_section(ms))) |
| continue; |
| |
| if (page_zone(pfn_to_page(pfn)) != zone) |
| continue; |
| |
| /* If the section is current section, it continues the loop */ |
| if (start_pfn == pfn) |
| continue; |
| |
| /* If we find valid section, we have nothing to do */ |
| zone_span_writeunlock(zone); |
| return; |
| } |
| |
| /* The zone has no valid section */ |
| zone->zone_start_pfn = 0; |
| zone->spanned_pages = 0; |
| zone_span_writeunlock(zone); |
| } |
| |
| static void shrink_pgdat_span(struct pglist_data *pgdat, |
| unsigned long start_pfn, unsigned long end_pfn) |
| { |
| unsigned long pgdat_start_pfn = pgdat->node_start_pfn; |
| unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */ |
| unsigned long pgdat_end_pfn = p; |
| unsigned long pfn; |
| struct mem_section *ms; |
| int nid = pgdat->node_id; |
| |
| if (pgdat_start_pfn == start_pfn) { |
| /* |
| * If the section is smallest section in the pgdat, it need |
| * shrink pgdat->node_start_pfn and pgdat->node_spanned_pages. |
| * In this case, we find second smallest valid mem_section |
| * for shrinking zone. |
| */ |
| pfn = find_smallest_section_pfn(nid, NULL, end_pfn, |
| pgdat_end_pfn); |
| if (pfn) { |
| pgdat->node_start_pfn = pfn; |
| pgdat->node_spanned_pages = pgdat_end_pfn - pfn; |
| } |
| } else if (pgdat_end_pfn == end_pfn) { |
| /* |
| * If the section is biggest section in the pgdat, it need |
| * shrink pgdat->node_spanned_pages. |
| * In this case, we find second biggest valid mem_section for |
| * shrinking zone. |
| */ |
| pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn, |
| start_pfn); |
| if (pfn) |
| pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1; |
| } |
| |
| /* |
| * If the section is not biggest or smallest mem_section in the pgdat, |
| * it only creates a hole in the pgdat. So in this case, we need not |
| * change the pgdat. |
| * But perhaps, the pgdat has only hole data. Thus it check the pgdat |
| * has only hole or not. |
| */ |
| pfn = pgdat_start_pfn; |
| for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) { |
| ms = __pfn_to_section(pfn); |
| |
| if (unlikely(!valid_section(ms))) |
| continue; |
| |
| if (pfn_to_nid(pfn) != nid) |
| continue; |
| |
| /* If the section is current section, it continues the loop */ |
| if (start_pfn == pfn) |
| continue; |
| |
| /* If we find valid section, we have nothing to do */ |
| return; |
| } |
| |
| /* The pgdat has no valid section */ |
| pgdat->node_start_pfn = 0; |
| pgdat->node_spanned_pages = 0; |
| } |
| |
| static void __remove_zone(struct zone *zone, unsigned long start_pfn) |
| { |
| struct pglist_data *pgdat = zone->zone_pgdat; |
| int nr_pages = PAGES_PER_SECTION; |
| unsigned long flags; |
| |
| pgdat_resize_lock(zone->zone_pgdat, &flags); |
| shrink_zone_span(zone, start_pfn, start_pfn + nr_pages); |
| shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages); |
| pgdat_resize_unlock(zone->zone_pgdat, &flags); |
| } |
| |
| static int __remove_section(struct zone *zone, struct mem_section *ms, |
| unsigned long map_offset, struct vmem_altmap *altmap) |
| { |
| unsigned long start_pfn; |
| int scn_nr; |
| int ret = -EINVAL; |
| |
| if (!valid_section(ms)) |
| return ret; |
| |
| ret = unregister_memory_section(ms); |
| if (ret) |
| return ret; |
| |
| scn_nr = __section_nr(ms); |
| start_pfn = section_nr_to_pfn((unsigned long)scn_nr); |
| __remove_zone(zone, start_pfn); |
| |
| sparse_remove_one_section(zone, ms, map_offset, altmap); |
| return 0; |
| } |
| |
| /** |
| * __remove_pages() - remove sections of pages from a zone |
| * @zone: zone from which pages need to be removed |
| * @phys_start_pfn: starting pageframe (must be aligned to start of a section) |
| * @nr_pages: number of pages to remove (must be multiple of section size) |
| * @altmap: alternative device page map or %NULL if default memmap is used |
| * |
| * Generic helper function to remove section mappings and sysfs entries |
| * for the section of the memory we are removing. Caller needs to make |
| * sure that pages are marked reserved and zones are adjust properly by |
| * calling offline_pages(). |
| */ |
| int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, |
| unsigned long nr_pages, struct vmem_altmap *altmap) |
| { |
| unsigned long i; |
| unsigned long map_offset = 0; |
| int sections_to_remove, ret = 0; |
| |
| /* In the ZONE_DEVICE case device driver owns the memory region */ |
| if (is_dev_zone(zone)) { |
| if (altmap) |
| map_offset = vmem_altmap_offset(altmap); |
| } else { |
| resource_size_t start, size; |
| |
| start = phys_start_pfn << PAGE_SHIFT; |
| size = nr_pages * PAGE_SIZE; |
| |
| ret = release_mem_region_adjustable(&iomem_resource, start, |
| size); |
| if (ret) { |
| resource_size_t endres = start + size - 1; |
| |
| pr_warn("Unable to release resource <%pa-%pa> (%d)\n", |
| &start, &endres, ret); |
| } |
| } |
| |
| clear_zone_contiguous(zone); |
| |
| /* |
| * We can only remove entire sections |
| */ |
| BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); |
| BUG_ON(nr_pages % PAGES_PER_SECTION); |
| |
| sections_to_remove = nr_pages / PAGES_PER_SECTION; |
| for (i = 0; i < sections_to_remove; i++) { |
| unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; |
| |
| ret = __remove_section(zone, __pfn_to_section(pfn), map_offset, |
| altmap); |
| map_offset = 0; |
| if (ret) |
| break; |
| } |
| |
| set_zone_contiguous(zone); |
| |
| return ret; |
| } |
| #endif /* CONFIG_MEMORY_HOTREMOVE */ |
| |
| int set_online_page_callback(online_page_callback_t callback) |
| { |
| int rc = -EINVAL; |
| |
| get_online_mems(); |
| mutex_lock(&online_page_callback_lock); |
| |
| if (online_page_callback == generic_online_page) { |
| online_page_callback = callback; |
| rc = 0; |
| } |
| |
| mutex_unlock(&online_page_callback_lock); |
| put_online_mems(); |
| |
| return rc; |
| } |
| EXPORT_SYMBOL_GPL(set_online_page_callback); |
| |
| int restore_online_page_callback(online_page_callback_t callback) |
| { |
| int rc = -EINVAL; |
| |
| get_online_mems(); |
| mutex_lock(&online_page_callback_lock); |
| |
| if (online_page_callback == callback) { |
| online_page_callback = generic_online_page; |
| rc = 0; |
| } |
| |
| mutex_unlock(&online_page_callback_lock); |
| put_online_mems(); |
| |
| return rc; |
| } |
| EXPORT_SYMBOL_GPL(restore_online_page_callback); |
| |
| void __online_page_set_limits(struct page *page) |
| { |
| } |
| EXPORT_SYMBOL_GPL(__online_page_set_limits); |
| |
| void __online_page_increment_counters(struct page *page) |
| { |
| adjust_managed_page_count(page, 1); |
| } |
| EXPORT_SYMBOL_GPL(__online_page_increment_counters); |
| |
| void __online_page_free(struct page *page) |
| { |
| __free_reserved_page(page); |
| } |
| EXPORT_SYMBOL_GPL(__online_page_free); |
| |
| static void generic_online_page(struct page *page) |
| { |
| __online_page_set_limits(page); |
| __online_page_increment_counters(page); |
| __online_page_free(page); |
| } |
| |
| static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, |
| void *arg) |
| { |
| unsigned long i; |
| unsigned long onlined_pages = *(unsigned long *)arg; |
| struct page *page; |
| |
| if (PageReserved(pfn_to_page(start_pfn))) |
| for (i = 0; i < nr_pages; i++) { |
| page = pfn_to_page(start_pfn + i); |
| (*online_page_callback)(page); |
| onlined_pages++; |
| } |
| |
| online_mem_sections(start_pfn, start_pfn + nr_pages); |
| |
| *(unsigned long *)arg = onlined_pages; |
| return 0; |
| } |
| |
| /* check which state of node_states will be changed when online memory */ |
| static void node_states_check_changes_online(unsigned long nr_pages, |
| struct zone *zone, struct memory_notify *arg) |
| { |
| int nid = zone_to_nid(zone); |
| |
| arg->status_change_nid = -1; |
| arg->status_change_nid_normal = -1; |
| arg->status_change_nid_high = -1; |
| |
| if (!node_state(nid, N_MEMORY)) |
| arg->status_change_nid = nid; |
| if (zone_idx(zone) <= ZONE_NORMAL && !node_state(nid, N_NORMAL_MEMORY)) |
| arg->status_change_nid_normal = nid; |
| #ifdef CONFIG_HIGHMEM |
| if (zone_idx(zone) <= N_HIGH_MEMORY && !node_state(nid, N_HIGH_MEMORY)) |
| arg->status_change_nid_high = nid; |
| #endif |
| } |
| |
| static void node_states_set_node(int node, struct memory_notify *arg) |
| { |
| if (arg->status_change_nid_normal >= 0) |
| node_set_state(node, N_NORMAL_MEMORY); |
| |
| if (arg->status_change_nid_high >= 0) |
| node_set_state(node, N_HIGH_MEMORY); |
| |
| if (arg->status_change_nid >= 0) |
| node_set_state(node, N_MEMORY); |
| } |
| |
| static void __meminit resize_zone_range(struct zone *zone, unsigned long start_pfn, |
| unsigned long nr_pages) |
| { |
| unsigned long old_end_pfn = zone_end_pfn(zone); |
| |
| if (zone_is_empty(zone) || start_pfn < zone->zone_start_pfn) |
| zone->zone_start_pfn = start_pfn; |
| |
| zone->spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - zone->zone_start_pfn; |
| } |
| |
| static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned long start_pfn, |
| unsigned long nr_pages) |
| { |
| unsigned long old_end_pfn = pgdat_end_pfn(pgdat); |
| |
| if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn) |
| pgdat->node_start_pfn = start_pfn; |
| |
| pgdat->node_spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - pgdat->node_start_pfn; |
| } |
| |
| void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, |
| unsigned long nr_pages, struct vmem_altmap *altmap) |
| { |
| struct pglist_data *pgdat = zone->zone_pgdat; |
| int nid = pgdat->node_id; |
| unsigned long flags; |
| |
| if (zone_is_empty(zone)) |
| init_currently_empty_zone(zone, start_pfn, nr_pages); |
| |
| clear_zone_contiguous(zone); |
| |
| /* TODO Huh pgdat is irqsave while zone is not. It used to be like that before */ |
| pgdat_resize_lock(pgdat, &flags); |
| zone_span_writelock(zone); |
| resize_zone_range(zone, start_pfn, nr_pages); |
| zone_span_writeunlock(zone); |
| resize_pgdat_range(pgdat, start_pfn, nr_pages); |
| pgdat_resize_unlock(pgdat, &flags); |
| |
| /* |
| * TODO now we have a visible range of pages which are not associated |
| * with their zone properly. Not nice but set_pfnblock_flags_mask |
| * expects the zone spans the pfn range. All the pages in the range |
| * are reserved so nobody should be touching them so we should be safe |
| */ |
| memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn, |
| MEMMAP_HOTPLUG, altmap); |
| |
| set_zone_contiguous(zone); |
| } |
| |
| /* |
| * Returns a default kernel memory zone for the given pfn range. |
| * If no kernel zone covers this pfn range it will automatically go |
| * to the ZONE_NORMAL. |
| */ |
| static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn, |
| unsigned long nr_pages) |
| { |
| struct pglist_data *pgdat = NODE_DATA(nid); |
| int zid; |
| |
| for (zid = 0; zid <= ZONE_NORMAL; zid++) { |
| struct zone *zone = &pgdat->node_zones[zid]; |
| |
| if (zone_intersects(zone, start_pfn, nr_pages)) |
| return zone; |
| } |
| |
| return &pgdat->node_zones[ZONE_NORMAL]; |
| } |
| |
| static inline struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn, |
| unsigned long nr_pages) |
| { |
| struct zone *kernel_zone = default_kernel_zone_for_pfn(nid, start_pfn, |
| nr_pages); |
| struct zone *movable_zone = &NODE_DATA(nid)->node_zones[ZONE_MOVABLE]; |
| bool in_kernel = zone_intersects(kernel_zone, start_pfn, nr_pages); |
| bool in_movable = zone_intersects(movable_zone, start_pfn, nr_pages); |
| |
| /* |
| * We inherit the existing zone in a simple case where zones do not |
| * overlap in the given range |
| */ |
| if (in_kernel ^ in_movable) |
| return (in_kernel) ? kernel_zone : movable_zone; |
| |
| /* |
| * If the range doesn't belong to any zone or two zones overlap in the |
| * given range then we use movable zone only if movable_node is |
| * enabled because we always online to a kernel zone by default. |
| */ |
| return movable_node_enabled ? movable_zone : kernel_zone; |
| } |
| |
| struct zone * zone_for_pfn_range(int online_type, int nid, unsigned start_pfn, |
| unsigned long nr_pages) |
| { |
| if (online_type == MMOP_ONLINE_KERNEL) |
| return default_kernel_zone_for_pfn(nid, start_pfn, nr_pages); |
| |
| if (online_type == MMOP_ONLINE_MOVABLE) |
| return &NODE_DATA(nid)->node_zones[ZONE_MOVABLE]; |
| |
| return default_zone_for_pfn(nid, start_pfn, nr_pages); |
| } |
| |
| /* |
| * Associates the given pfn range with the given node and the zone appropriate |
| * for the given online type. |
| */ |
| static struct zone * __meminit move_pfn_range(int online_type, int nid, |
| unsigned long start_pfn, unsigned long nr_pages) |
| { |
| struct zone *zone; |
| |
| zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages); |
| move_pfn_range_to_zone(zone, start_pfn, nr_pages, NULL); |
| return zone; |
| } |
| |
| /* Must be protected by mem_hotplug_begin() or a device_lock */ |
| int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type) |
| { |
| unsigned long flags; |
| unsigned long onlined_pages = 0; |
| struct zone *zone; |
| int need_zonelists_rebuild = 0; |
| int nid; |
| int ret; |
| struct memory_notify arg; |
| struct memory_block *mem; |
| |
| /* |
| * We can't use pfn_to_nid() because nid might be stored in struct page |
| * which is not yet initialized. Instead, we find nid from memory block. |
| */ |
| mem = find_memory_block(__pfn_to_section(pfn)); |
| nid = mem->nid; |
| |
| /* associate pfn range with the zone */ |
| zone = move_pfn_range(online_type, nid, pfn, nr_pages); |
| |
| arg.start_pfn = pfn; |
| arg.nr_pages = nr_pages; |
| node_states_check_changes_online(nr_pages, zone, &arg); |
| |
| ret = memory_notify(MEM_GOING_ONLINE, &arg); |
| ret = notifier_to_errno(ret); |
| if (ret) |
| goto failed_addition; |
| |
| /* |
| * If this zone is not populated, then it is not in zonelist. |
| * This means the page allocator ignores this zone. |
| * So, zonelist must be updated after online. |
| */ |
| if (!populated_zone(zone)) { |
| need_zonelists_rebuild = 1; |
| setup_zone_pageset(zone); |
| } |
| |
| ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages, |
| online_pages_range); |
| if (ret) { |
| if (need_zonelists_rebuild) |
| zone_pcp_reset(zone); |
| goto failed_addition; |
| } |
| |
| zone->present_pages += onlined_pages; |
| |
| pgdat_resize_lock(zone->zone_pgdat, &flags); |
| zone->zone_pgdat->node_present_pages += onlined_pages; |
| pgdat_resize_unlock(zone->zone_pgdat, &flags); |
| |
| if (onlined_pages) { |
| node_states_set_node(nid, &arg); |
| if (need_zonelists_rebuild) |
| build_all_zonelists(NULL); |
| else |
| zone_pcp_update(zone); |
| } |
| |
| init_per_zone_wmark_min(); |
| |
| if (onlined_pages) { |
| kswapd_run(nid); |
| kcompactd_run(nid); |
| } |
| |
| vm_total_pages = nr_free_pagecache_pages(); |
| |
| writeback_set_ratelimit(); |
| |
| if (onlined_pages) |
| memory_notify(MEM_ONLINE, &arg); |
| return 0; |
| |
| failed_addition: |
| pr_debug("online_pages [mem %#010llx-%#010llx] failed\n", |
| (unsigned long long) pfn << PAGE_SHIFT, |
| (((unsigned long long) pfn + nr_pages) << PAGE_SHIFT) - 1); |
| memory_notify(MEM_CANCEL_ONLINE, &arg); |
| return ret; |
| } |
| #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ |
| |
| static void reset_node_present_pages(pg_data_t *pgdat) |
| { |
| struct zone *z; |
| |
| for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) |
| z->present_pages = 0; |
| |
| pgdat->node_present_pages = 0; |
| } |
| |
| /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ |
| static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) |
| { |
| struct pglist_data *pgdat; |
| unsigned long start_pfn = PFN_DOWN(start); |
| |
| pgdat = NODE_DATA(nid); |
| if (!pgdat) { |
| pgdat = arch_alloc_nodedata(nid); |
| if (!pgdat) |
| return NULL; |
| |
| arch_refresh_nodedata(nid, pgdat); |
| } else { |
| /* |
| * Reset the nr_zones, order and classzone_idx before reuse. |
| * Note that kswapd will init kswapd_classzone_idx properly |
| * when it starts in the near future. |
| */ |
| pgdat->nr_zones = 0; |
| pgdat->kswapd_order = 0; |
| pgdat->kswapd_classzone_idx = 0; |
| } |
| |
| /* we can use NODE_DATA(nid) from here */ |
| |
| pgdat->node_id = nid; |
| pgdat->node_start_pfn = start_pfn; |
| |
| /* init node's zones as empty zones, we don't have any present pages.*/ |
| free_area_init_core_hotplug(nid); |
| pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); |
| |
| /* |
| * The node we allocated has no zone fallback lists. For avoiding |
| * to access not-initialized zonelist, build here. |
| */ |
| build_all_zonelists(pgdat); |
| |
| /* |
| * When memory is hot-added, all the memory is in offline state. So |
| * clear all zones' present_pages because they will be updated in |
| * online_pages() and offline_pages(). |
| */ |
| reset_node_managed_pages(pgdat); |
| reset_node_present_pages(pgdat); |
| |
| return pgdat; |
| } |
| |
| static void rollback_node_hotadd(int nid) |
| { |
| pg_data_t *pgdat = NODE_DATA(nid); |
| |
| arch_refresh_nodedata(nid, NULL); |
| free_percpu(pgdat->per_cpu_nodestats); |
| arch_free_nodedata(pgdat); |
| return; |
| } |
| |
| |
| /** |
| * try_online_node - online a node if offlined |
| * @nid: the node ID |
| * @start: start addr of the node |
| * @set_node_online: Whether we want to online the node |
| * called by cpu_up() to online a node without onlined memory. |
| * |
| * Returns: |
| * 1 -> a new node has been allocated |
| * 0 -> the node is already online |
| * -ENOMEM -> the node could not be allocated |
| */ |
| static int __try_online_node(int nid, u64 start, bool set_node_online) |
| { |
| pg_data_t *pgdat; |
| int ret = 1; |
| |
| if (node_online(nid)) |
| return 0; |
| |
| pgdat = hotadd_new_pgdat(nid, start); |
| if (!pgdat) { |
| pr_err("Cannot online node %d due to NULL pgdat\n", nid); |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (set_node_online) { |
| node_set_online(nid); |
| ret = register_one_node(nid); |
| BUG_ON(ret); |
| } |
| out: |
| return ret; |
| } |
| |
| /* |
| * Users of this function always want to online/register the node |
| */ |
| int try_online_node(int nid) |
| { |
| int ret; |
| |
| mem_hotplug_begin(); |
| ret = __try_online_node(nid, 0, true); |
| mem_hotplug_done(); |
| return ret; |
| } |
| |
| static int check_hotplug_memory_range(u64 start, u64 size) |
| { |
| unsigned long block_sz = memory_block_size_bytes(); |
| u64 block_nr_pages = block_sz >> PAGE_SHIFT; |
| u64 nr_pages = size >> PAGE_SHIFT; |
| u64 start_pfn = PFN_DOWN(start); |
| |
| /* memory range must be block size aligned */ |
| if (!nr_pages || !IS_ALIGNED(start_pfn, block_nr_pages) || |
| !IS_ALIGNED(nr_pages, block_nr_pages)) { |
| pr_err("Block size [%#lx] unaligned hotplug range: start %#llx, size %#llx", |
| block_sz, start, size); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int online_memory_block(struct memory_block *mem, void *arg) |
| { |
| return device_online(&mem->dev); |
| } |
| |
| /* |
| * NOTE: The caller must call lock_device_hotplug() to serialize hotplug |
| * and online/offline operations (triggered e.g. by sysfs). |
| * |
| * we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG |
| */ |
| int __ref add_memory_resource(int nid, struct resource *res, bool online) |
| { |
| u64 start, size; |
| bool new_node = false; |
| int ret; |
| |
| start = res->start; |
| size = resource_size(res); |
| |
| ret = check_hotplug_memory_range(start, size); |
| if (ret) |
| return ret; |
| |
| mem_hotplug_begin(); |
| |
| /* |
| * Add new range to memblock so that when hotadd_new_pgdat() is called |
| * to allocate new pgdat, get_pfn_range_for_nid() will be able to find |
| * this new range and calculate total pages correctly. The range will |
| * be removed at hot-remove time. |
| */ |
| memblock_add_node(start, size, nid); |
| |
| ret = __try_online_node(nid, start, false); |
| if (ret < 0) |
| goto error; |
| new_node = ret; |
| |
| /* call arch's memory hotadd */ |
| ret = arch_add_memory(nid, start, size, NULL, true); |
| if (ret < 0) |
| goto error; |
| |
| if (new_node) { |
| /* If sysfs file of new node can't be created, cpu on the node |
| * can't be hot-added. There is no rollback way now. |
| * So, check by BUG_ON() to catch it reluctantly.. |
| * We online node here. We can't roll back from here. |
| */ |
| node_set_online(nid); |
| ret = __register_one_node(nid); |
| BUG_ON(ret); |
| } |
| |
| /* link memory sections under this node.*/ |
| ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1)); |
| BUG_ON(ret); |
| |
| /* create new memmap entry */ |
| firmware_map_add_hotplug(start, start + size, "System RAM"); |
| |
| /* online pages if requested */ |
| if (online) |
| walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), |
| NULL, online_memory_block); |
| |
| goto out; |
| |
| error: |
| /* rollback pgdat allocation and others */ |
| if (new_node) |
| rollback_node_hotadd(nid); |
| memblock_remove(start, size); |
| |
| out: |
| mem_hotplug_done(); |
| return ret; |
| } |
| |
| /* requires device_hotplug_lock, see add_memory_resource() */ |
| int __ref __add_memory(int nid, u64 start, u64 size) |
| { |
| struct resource *res; |
| int ret; |
| |
| res = register_memory_resource(start, size); |
| if (IS_ERR(res)) |
| return PTR_ERR(res); |
| |
| ret = add_memory_resource(nid, res, memhp_auto_online); |
| if (ret < 0) |
| release_memory_resource(res); |
| return ret; |
| } |
| |
| int add_memory(int nid, u64 start, u64 size) |
| { |
| int rc; |
| |
| lock_device_hotplug(); |
| rc = __add_memory(nid, start, size); |
| unlock_device_hotplug(); |
| |
| return rc; |
| } |
| EXPORT_SYMBOL_GPL(add_memory); |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| /* |
| * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy |
| * set and the size of the free page is given by page_order(). Using this, |
| * the function determines if the pageblock contains only free pages. |
| * Due to buddy contraints, a free page at least the size of a pageblock will |
| * be located at the start of the pageblock |
| */ |
| static inline int pageblock_free(struct page *page) |
| { |
| return PageBuddy(page) && page_order(page) >= pageblock_order; |
| } |
| |
| /* Return the start of the next active pageblock after a given page */ |
| static struct page *next_active_pageblock(struct page *page) |
| { |
| /* Ensure the starting page is pageblock-aligned */ |
| BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1)); |
| |
| /* If the entire pageblock is free, move to the end of free page */ |
| if (pageblock_free(page)) { |
| int order; |
| /* be careful. we don't have locks, page_order can be changed.*/ |
| order = page_order(page); |
| if ((order < MAX_ORDER) && (order >= pageblock_order)) |
| return page + (1 << order); |
| } |
| |
| return page + pageblock_nr_pages; |
| } |
| |
| static bool is_pageblock_removable_nolock(struct page *page) |
| { |
| struct zone *zone; |
| unsigned long pfn; |
| |
| /* |
| * We have to be careful here because we are iterating over memory |
| * sections which are not zone aware so we might end up outside of |
| * the zone but still within the section. |
| * We have to take care about the node as well. If the node is offline |
| * its NODE_DATA will be NULL - see page_zone. |
| */ |
| if (!node_online(page_to_nid(page))) |
| return false; |
| |
| zone = page_zone(page); |
| pfn = page_to_pfn(page); |
| if (!zone_spans_pfn(zone, pfn)) |
| return false; |
| |
| return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true); |
| } |
| |
| /* Checks if this range of memory is likely to be hot-removable. */ |
| bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) |
| { |
| struct page *page = pfn_to_page(start_pfn); |
| struct page *end_page = page + nr_pages; |
| |
| /* Check the starting page of each pageblock within the range */ |
| for (; page < end_page; page = next_active_pageblock(page)) { |
| if (!is_pageblock_removable_nolock(page)) |
| return false; |
| cond_resched(); |
| } |
| |
| /* All pageblocks in the memory block are likely to be hot-removable */ |
| return true; |
| } |
| |
| /* |
| * Confirm all pages in a range [start, end) belong to the same zone. |
| * When true, return its valid [start, end). |
| */ |
| int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, |
| unsigned long *valid_start, unsigned long *valid_end) |
| { |
| unsigned long pfn, sec_end_pfn; |
| unsigned long start, end; |
| struct zone *zone = NULL; |
| struct page *page; |
| int i; |
| for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn + 1); |
| pfn < end_pfn; |
| pfn = sec_end_pfn, sec_end_pfn += PAGES_PER_SECTION) { |
| /* Make sure the memory section is present first */ |
| if (!present_section_nr(pfn_to_section_nr(pfn))) |
| continue; |
| for (; pfn < sec_end_pfn && pfn < end_pfn; |
| pfn += MAX_ORDER_NR_PAGES) { |
| i = 0; |
| /* This is just a CONFIG_HOLES_IN_ZONE check.*/ |
| while ((i < MAX_ORDER_NR_PAGES) && |
| !pfn_valid_within(pfn + i)) |
| i++; |
| if (i == MAX_ORDER_NR_PAGES || pfn + i >= end_pfn) |
| continue; |
| page = pfn_to_page(pfn + i); |
| if (zone && page_zone(page) != zone) |
| return 0; |
| if (!zone) |
| start = pfn + i; |
| zone = page_zone(page); |
| end = pfn + MAX_ORDER_NR_PAGES; |
| } |
| } |
| |
| if (zone) { |
| *valid_start = start; |
| *valid_end = min(end, end_pfn); |
| return 1; |
| } else { |
| return 0; |
| } |
| } |
| |
| /* |
| * Scan pfn range [start,end) to find movable/migratable pages (LRU pages, |
| * non-lru movable pages and hugepages). We scan pfn because it's much |
| * easier than scanning over linked list. This function returns the pfn |
| * of the first found movable page if it's found, otherwise 0. |
| */ |
| static unsigned long scan_movable_pages(unsigned long start, unsigned long end) |
| { |
| unsigned long pfn; |
| struct page *page; |
| for (pfn = start; pfn < end; pfn++) { |
| if (pfn_valid(pfn)) { |
| page = pfn_to_page(pfn); |
| if (PageLRU(page)) |
| return pfn; |
| if (__PageMovable(page)) |
| return pfn; |
| if (PageHuge(page)) { |
| if (hugepage_migration_supported(page_hstate(page)) && |
| page_huge_active(page)) |
| return pfn; |
| else |
| pfn = round_up(pfn + 1, |
| 1 << compound_order(page)) - 1; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| static struct page *new_node_page(struct page *page, unsigned long private) |
| { |
| int nid = page_to_nid(page); |
| nodemask_t nmask = node_states[N_MEMORY]; |
| |
| /* |
| * try to allocate from a different node but reuse this node if there |
| * are no other online nodes to be used (e.g. we are offlining a part |
| * of the only existing node) |
| */ |
| node_clear(nid, nmask); |
| if (nodes_empty(nmask)) |
| node_set(nid, nmask); |
| |
| return new_page_nodemask(page, nid, &nmask); |
| } |
| |
| #define NR_OFFLINE_AT_ONCE_PAGES (256) |
| static int |
| do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) |
| { |
| unsigned long pfn; |
| struct page *page; |
| int move_pages = NR_OFFLINE_AT_ONCE_PAGES; |
| int not_managed = 0; |
| int ret = 0; |
| LIST_HEAD(source); |
| |
| for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) { |
| if (!pfn_valid(pfn)) |
| continue; |
| page = pfn_to_page(pfn); |
| |
| if (PageHuge(page)) { |
| struct page *head = compound_head(page); |
| pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1; |
| if (compound_order(head) > PFN_SECTION_SHIFT) { |
| ret = -EBUSY; |
| break; |
| } |
| if (isolate_huge_page(page, &source)) |
| move_pages -= 1 << compound_order(head); |
| continue; |
| } else if (PageTransHuge(page)) |
| pfn = page_to_pfn(compound_head(page)) |
| + hpage_nr_pages(page) - 1; |
| |
| if (!get_page_unless_zero(page)) |
| continue; |
| /* |
| * We can skip free pages. And we can deal with pages on |
| * LRU and non-lru movable pages. |
| */ |
| if (PageLRU(page)) |
| ret = isolate_lru_page(page); |
| else |
| ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE); |
| if (!ret) { /* Success */ |
| put_page(page); |
| list_add_tail(&page->lru, &source); |
| move_pages--; |
| if (!__PageMovable(page)) |
| inc_node_page_state(page, NR_ISOLATED_ANON + |
| page_is_file_cache(page)); |
| |
| } else { |
| #ifdef CONFIG_DEBUG_VM |
| pr_alert("failed to isolate pfn %lx\n", pfn); |
| dump_page(page, "isolation failed"); |
| #endif |
| put_page(page); |
| /* Because we don't have big zone->lock. we should |
| check this again here. */ |
| if (page_count(page)) { |
| not_managed++; |
| ret = -EBUSY; |
| break; |
| } |
| } |
| } |
| if (!list_empty(&source)) { |
| if (not_managed) { |
| putback_movable_pages(&source); |
| goto out; |
| } |
| |
| /* Allocate a new page from the nearest neighbor node */ |
| ret = migrate_pages(&source, new_node_page, NULL, 0, |
| MIGRATE_SYNC, MR_MEMORY_HOTPLUG); |
| if (ret) |
| putback_movable_pages(&source); |
| } |
| out: |
| return ret; |
| } |
| |
| /* |
| * remove from free_area[] and mark all as Reserved. |
| */ |
| static int |
| offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages, |
| void *data) |
| { |
| __offline_isolated_pages(start, start + nr_pages); |
| return 0; |
| } |
| |
| static void |
| offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) |
| { |
| walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL, |
| offline_isolated_pages_cb); |
| } |
| |
| /* |
| * Check all pages in range, recoreded as memory resource, are isolated. |
| */ |
| static int |
| check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages, |
| void *data) |
| { |
| int ret; |
| long offlined = *(long *)data; |
| ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true); |
| offlined = nr_pages; |
| if (!ret) |
| *(long *)data += offlined; |
| return ret; |
| } |
| |
| static long |
| check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn) |
| { |
| long offlined = 0; |
| int ret; |
| |
| ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined, |
| check_pages_isolated_cb); |
| if (ret < 0) |
| offlined = (long)ret; |
| return offlined; |
| } |
| |
| static int __init cmdline_parse_movable_node(char *p) |
| { |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| movable_node_enabled = true; |
| #else |
| pr_warn("movable_node parameter depends on CONFIG_HAVE_MEMBLOCK_NODE_MAP to work properly\n"); |
| #endif |
| return 0; |
| } |
| early_param("movable_node", cmdline_parse_movable_node); |
| |
| /* check which state of node_states will be changed when offline memory */ |
| static void node_states_check_changes_offline(unsigned long nr_pages, |
| struct zone *zone, struct memory_notify *arg) |
| { |
| struct pglist_data *pgdat = zone->zone_pgdat; |
| unsigned long present_pages = 0; |
| enum zone_type zt; |
| |
| arg->status_change_nid = -1; |
| arg->status_change_nid_normal = -1; |
| arg->status_change_nid_high = -1; |
| |
| /* |
| * Check whether node_states[N_NORMAL_MEMORY] will be changed. |
| * If the memory to be offline is within the range |
| * [0..ZONE_NORMAL], and it is the last present memory there, |
| * the zones in that range will become empty after the offlining, |
| * thus we can determine that we need to clear the node from |
| * node_states[N_NORMAL_MEMORY]. |
| */ |
| for (zt = 0; zt <= ZONE_NORMAL; zt++) |
| present_pages += pgdat->node_zones[zt].present_pages; |
| if (zone_idx(zone) <= ZONE_NORMAL && nr_pages >= present_pages) |
| arg->status_change_nid_normal = zone_to_nid(zone); |
| |
| #ifdef CONFIG_HIGHMEM |
| /* |
| * node_states[N_HIGH_MEMORY] contains nodes which |
| * have normal memory or high memory. |
| * Here we add the present_pages belonging to ZONE_HIGHMEM. |
| * If the zone is within the range of [0..ZONE_HIGHMEM), and |
| * we determine that the zones in that range become empty, |
| * we need to clear the node for N_HIGH_MEMORY. |
| */ |
| present_pages += pgdat->node_zones[ZONE_HIGHMEM].present_pages; |
| if (zone_idx(zone) <= ZONE_HIGHMEM && nr_pages >= present_pages) |
| arg->status_change_nid_high = zone_to_nid(zone); |
| #endif |
| |
| /* |
| * We have accounted the pages from [0..ZONE_NORMAL), and |
| * in case of CONFIG_HIGHMEM the pages from ZONE_HIGHMEM |
| * as well. |
| * Here we count the possible pages from ZONE_MOVABLE. |
| * If after having accounted all the pages, we see that the nr_pages |
| * to be offlined is over or equal to the accounted pages, |
| * we know that the node will become empty, and so, we can clear |
| * it for N_MEMORY as well. |
| */ |
| present_pages += pgdat->node_zones[ZONE_MOVABLE].present_pages; |
| |
| if (nr_pages >= present_pages) |
| arg->status_change_nid = zone_to_nid(zone); |
| } |
| |
| static void node_states_clear_node(int node, struct memory_notify *arg) |
| { |
| if (arg->status_change_nid_normal >= 0) |
| node_clear_state(node, N_NORMAL_MEMORY); |
| |
| if (arg->status_change_nid_high >= 0) |
| node_clear_state(node, N_HIGH_MEMORY); |
| |
| if (arg->status_change_nid >= 0) |
| node_clear_state(node, N_MEMORY); |
| } |
| |
| static int __ref __offline_pages(unsigned long start_pfn, |
| unsigned long end_pfn) |
| { |
| unsigned long pfn, nr_pages; |
| long offlined_pages; |
| int ret, node; |
| unsigned long flags; |
| unsigned long valid_start, valid_end; |
| struct zone *zone; |
| struct memory_notify arg; |
| |
| /* at least, alignment against pageblock is necessary */ |
| if (!IS_ALIGNED(start_pfn, pageblock_nr_pages)) |
| return -EINVAL; |
| if (!IS_ALIGNED(end_pfn, pageblock_nr_pages)) |
| return -EINVAL; |
| /* This makes hotplug much easier...and readable. |
| we assume this for now. .*/ |
| if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end)) |
| return -EINVAL; |
| |
| zone = page_zone(pfn_to_page(valid_start)); |
| node = zone_to_nid(zone); |
| nr_pages = end_pfn - start_pfn; |
| |
| /* set above range as isolated */ |
| ret = start_isolate_page_range(start_pfn, end_pfn, |
| MIGRATE_MOVABLE, true); |
| if (ret) |
| return ret; |
| |
| arg.start_pfn = start_pfn; |
| arg.nr_pages = nr_pages; |
| node_states_check_changes_offline(nr_pages, zone, &arg); |
| |
| ret = memory_notify(MEM_GOING_OFFLINE, &arg); |
| ret = notifier_to_errno(ret); |
| if (ret) |
| goto failed_removal; |
| |
| pfn = start_pfn; |
| repeat: |
| /* start memory hot removal */ |
| ret = -EINTR; |
| if (signal_pending(current)) |
| goto failed_removal; |
| |
| cond_resched(); |
| lru_add_drain_all(); |
| drain_all_pages(zone); |
| |
| pfn = scan_movable_pages(start_pfn, end_pfn); |
| if (pfn) { /* We have movable pages */ |
| ret = do_migrate_range(pfn, end_pfn); |
| goto repeat; |
| } |
| |
| /* |
| * dissolve free hugepages in the memory block before doing offlining |
| * actually in order to make hugetlbfs's object counting consistent. |
| */ |
| ret = dissolve_free_huge_pages(start_pfn, end_pfn); |
| if (ret) |
| goto failed_removal; |
| /* check again */ |
| offlined_pages = check_pages_isolated(start_pfn, end_pfn); |
| if (offlined_pages < 0) |
| goto repeat; |
| pr_info("Offlined Pages %ld\n", offlined_pages); |
| /* Ok, all of our target is isolated. |
| We cannot do rollback at this point. */ |
| offline_isolated_pages(start_pfn, end_pfn); |
| /* reset pagetype flags and makes migrate type to be MOVABLE */ |
| undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); |
| /* removal success */ |
| adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages); |
| zone->present_pages -= offlined_pages; |
| |
| pgdat_resize_lock(zone->zone_pgdat, &flags); |
| zone->zone_pgdat->node_present_pages -= offlined_pages; |
| pgdat_resize_unlock(zone->zone_pgdat, &flags); |
| |
| init_per_zone_wmark_min(); |
| |
| if (!populated_zone(zone)) { |
| zone_pcp_reset(zone); |
| build_all_zonelists(NULL); |
| } else |
| zone_pcp_update(zone); |
| |
| node_states_clear_node(node, &arg); |
| if (arg.status_change_nid >= 0) { |
| kswapd_stop(node); |
| kcompactd_stop(node); |
| } |
| |
| vm_total_pages = nr_free_pagecache_pages(); |
| writeback_set_ratelimit(); |
| |
| memory_notify(MEM_OFFLINE, &arg); |
| return 0; |
| |
| failed_removal: |
| pr_debug("memory offlining [mem %#010llx-%#010llx] failed\n", |
| (unsigned long long) start_pfn << PAGE_SHIFT, |
| ((unsigned long long) end_pfn << PAGE_SHIFT) - 1); |
| memory_notify(MEM_CANCEL_OFFLINE, &arg); |
| /* pushback to free area */ |
| undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); |
| return ret; |
| } |
| |
| /* Must be protected by mem_hotplug_begin() or a device_lock */ |
| int offline_pages(unsigned long start_pfn, unsigned long nr_pages) |
| { |
| return __offline_pages(start_pfn, start_pfn + nr_pages); |
| } |
| #endif /* CONFIG_MEMORY_HOTREMOVE */ |
| |
| /** |
| * walk_memory_range - walks through all mem sections in [start_pfn, end_pfn) |
| * @start_pfn: start pfn of the memory range |
| * @end_pfn: end pfn of the memory range |
| * @arg: argument passed to func |
| * @func: callback for each memory section walked |
| * |
| * This function walks through all present mem sections in range |
| * [start_pfn, end_pfn) and call func on each mem section. |
| * |
| * Returns the return value of func. |
| */ |
| int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, |
| void *arg, int (*func)(struct memory_block *, void *)) |
| { |
| struct memory_block *mem = NULL; |
| struct mem_section *section; |
| unsigned long pfn, section_nr; |
| int ret; |
| |
| for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { |
| section_nr = pfn_to_section_nr(pfn); |
| if (!present_section_nr(section_nr)) |
| continue; |
| |
| section = __nr_to_section(section_nr); |
| /* same memblock? */ |
| if (mem) |
| if ((section_nr >= mem->start_section_nr) && |
| (section_nr <= mem->end_section_nr)) |
| continue; |
| |
| mem = find_memory_block_hinted(section, mem); |
| if (!mem) |
| continue; |
| |
| ret = func(mem, arg); |
| if (ret) { |
| kobject_put(&mem->dev.kobj); |
| return ret; |
| } |
| } |
| |
| if (mem) |
| kobject_put(&mem->dev.kobj); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| static int check_memblock_offlined_cb(struct memory_block *mem, void *arg) |
| { |
| int ret = !is_memblock_offlined(mem); |
| |
| if (unlikely(ret)) { |
| phys_addr_t beginpa, endpa; |
| |
| beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)); |
| endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1; |
| pr_warn("removing memory fails, because memory [%pa-%pa] is onlined\n", |
| &beginpa, &endpa); |
| } |
| |
| return ret; |
| } |
| |
| static int check_cpu_on_node(pg_data_t *pgdat) |
| { |
| int cpu; |
| |
| for_each_present_cpu(cpu) { |
| if (cpu_to_node(cpu) == pgdat->node_id) |
| /* |
| * the cpu on this node isn't removed, and we can't |
| * offline this node. |
| */ |
| return -EBUSY; |
| } |
| |
| return 0; |
| } |
| |
| static void unmap_cpu_on_node(pg_data_t *pgdat) |
| { |
| #ifdef CONFIG_ACPI_NUMA |
| int cpu; |
| |
| for_each_possible_cpu(cpu) |
| if (cpu_to_node(cpu) == pgdat->node_id) |
| numa_clear_node(cpu); |
| #endif |
| } |
| |
| static int check_and_unmap_cpu_on_node(pg_data_t *pgdat) |
| { |
| int ret; |
| |
| ret = check_cpu_on_node(pgdat); |
| if (ret) |
| return ret; |
| |
| /* |
| * the node will be offlined when we come here, so we can clear |
| * the cpu_to_node() now. |
| */ |
| |
| unmap_cpu_on_node(pgdat); |
| return 0; |
| } |
| |
| /** |
| * try_offline_node |
| * @nid: the node ID |
| * |
| * Offline a node if all memory sections and cpus of the node are removed. |
| * |
| * NOTE: The caller must call lock_device_hotplug() to serialize hotplug |
| * and online/offline operations before this call. |
| */ |
| void try_offline_node(int nid) |
| { |
| pg_data_t *pgdat = NODE_DATA(nid); |
| unsigned long start_pfn = pgdat->node_start_pfn; |
| unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages; |
| unsigned long pfn; |
| |
| for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { |
| unsigned long section_nr = pfn_to_section_nr(pfn); |
| |
| if (!present_section_nr(section_nr)) |
| continue; |
| |
| if (pfn_to_nid(pfn) != nid) |
| continue; |
| |
| /* |
| * some memory sections of this node are not removed, and we |
| * can't offline node now. |
| */ |
| return; |
| } |
| |
| if (check_and_unmap_cpu_on_node(pgdat)) |
| return; |
| |
| /* |
| * all memory/cpu of this node are removed, we can offline this |
| * node now. |
| */ |
| node_set_offline(nid); |
| unregister_one_node(nid); |
| } |
| EXPORT_SYMBOL(try_offline_node); |
| |
| /** |
| * remove_memory |
| * @nid: the node ID |
| * @start: physical address of the region to remove |
| * @size: size of the region to remove |
| * |
| * NOTE: The caller must call lock_device_hotplug() to serialize hotplug |
| * and online/offline operations before this call, as required by |
| * try_offline_node(). |
| */ |
| void __ref __remove_memory(int nid, u64 start, u64 size) |
| { |
| int ret; |
| |
| BUG_ON(check_hotplug_memory_range(start, size)); |
| |
| mem_hotplug_begin(); |
| |
| /* |
| * All memory blocks must be offlined before removing memory. Check |
| * whether all memory blocks in question are offline and trigger a BUG() |
| * if this is not the case. |
| */ |
| ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL, |
| check_memblock_offlined_cb); |
| if (ret) |
| BUG(); |
| |
| /* remove memmap entry */ |
| firmware_map_remove(start, start + size, "System RAM"); |
| memblock_free(start, size); |
| memblock_remove(start, size); |
| |
| arch_remove_memory(start, size, NULL); |
| |
| try_offline_node(nid); |
| |
| mem_hotplug_done(); |
| } |
| |
| void remove_memory(int nid, u64 start, u64 size) |
| { |
| lock_device_hotplug(); |
| __remove_memory(nid, start, size); |
| unlock_device_hotplug(); |
| } |
| EXPORT_SYMBOL_GPL(remove_memory); |
| #endif /* CONFIG_MEMORY_HOTREMOVE */ |