1 /* 2 * linux/mm/memory_hotplug.c 3 * 4 * Copyright (C) 5 */ 6 7 #include <linux/config.h> 8 #include <linux/stddef.h> 9 #include <linux/mm.h> 10 #include <linux/swap.h> 11 #include <linux/interrupt.h> 12 #include <linux/pagemap.h> 13 #include <linux/bootmem.h> 14 #include <linux/compiler.h> 15 #include <linux/module.h> 16 #include <linux/pagevec.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 25 #include <asm/tlbflush.h> 26 27 extern void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn, 28 unsigned long size); 29 static void __add_zone(struct zone *zone, unsigned long phys_start_pfn) 30 { 31 struct pglist_data *pgdat = zone->zone_pgdat; 32 int nr_pages = PAGES_PER_SECTION; 33 int nid = pgdat->node_id; 34 int zone_type; 35 36 zone_type = zone - pgdat->node_zones; 37 memmap_init_zone(nr_pages, nid, zone_type, phys_start_pfn); 38 zonetable_add(zone, nid, zone_type, phys_start_pfn, nr_pages); 39 } 40 41 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn, 42 int nr_pages); 43 static int __add_section(struct zone *zone, unsigned long phys_start_pfn) 44 { 45 struct pglist_data *pgdat = zone->zone_pgdat; 46 int nr_pages = PAGES_PER_SECTION; 47 int ret; 48 49 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages); 50 51 if (ret < 0) 52 return ret; 53 54 __add_zone(zone, phys_start_pfn); 55 return register_new_memory(__pfn_to_section(phys_start_pfn)); 56 } 57 58 /* 59 * Reasonably generic function for adding memory. It is 60 * expected that archs that support memory hotplug will 61 * call this function after deciding the zone to which to 62 * add the new pages. 63 */ 64 int __add_pages(struct zone *zone, unsigned long phys_start_pfn, 65 unsigned long nr_pages) 66 { 67 unsigned long i; 68 int err = 0; 69 70 for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) { 71 err = __add_section(zone, phys_start_pfn + i); 72 73 if (err) 74 break; 75 } 76 77 return err; 78 } 79 80 static void grow_zone_span(struct zone *zone, 81 unsigned long start_pfn, unsigned long end_pfn) 82 { 83 unsigned long old_zone_end_pfn; 84 85 zone_span_writelock(zone); 86 87 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages; 88 if (start_pfn < zone->zone_start_pfn) 89 zone->zone_start_pfn = start_pfn; 90 91 if (end_pfn > old_zone_end_pfn) 92 zone->spanned_pages = end_pfn - zone->zone_start_pfn; 93 94 zone_span_writeunlock(zone); 95 } 96 97 static void grow_pgdat_span(struct pglist_data *pgdat, 98 unsigned long start_pfn, unsigned long end_pfn) 99 { 100 unsigned long old_pgdat_end_pfn = 101 pgdat->node_start_pfn + pgdat->node_spanned_pages; 102 103 if (start_pfn < pgdat->node_start_pfn) 104 pgdat->node_start_pfn = start_pfn; 105 106 if (end_pfn > old_pgdat_end_pfn) 107 pgdat->node_spanned_pages = end_pfn - pgdat->node_spanned_pages; 108 } 109 110 int online_pages(unsigned long pfn, unsigned long nr_pages) 111 { 112 unsigned long i; 113 unsigned long flags; 114 unsigned long onlined_pages = 0; 115 struct zone *zone; 116 117 /* 118 * This doesn't need a lock to do pfn_to_page(). 119 * The section can't be removed here because of the 120 * memory_block->state_sem. 121 */ 122 zone = page_zone(pfn_to_page(pfn)); 123 pgdat_resize_lock(zone->zone_pgdat, &flags); 124 grow_zone_span(zone, pfn, pfn + nr_pages); 125 grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages); 126 pgdat_resize_unlock(zone->zone_pgdat, &flags); 127 128 for (i = 0; i < nr_pages; i++) { 129 struct page *page = pfn_to_page(pfn + i); 130 online_page(page); 131 onlined_pages++; 132 } 133 zone->present_pages += onlined_pages; 134 135 setup_per_zone_pages_min(); 136 137 return 0; 138 } 139