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 int nr_pages = PAGES_PER_SECTION; 46 int ret; 47 48 ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages); 49 50 if (ret < 0) 51 return ret; 52 53 __add_zone(zone, phys_start_pfn); 54 return register_new_memory(__pfn_to_section(phys_start_pfn)); 55 } 56 57 /* 58 * Reasonably generic function for adding memory. It is 59 * expected that archs that support memory hotplug will 60 * call this function after deciding the zone to which to 61 * add the new pages. 62 */ 63 int __add_pages(struct zone *zone, unsigned long phys_start_pfn, 64 unsigned long nr_pages) 65 { 66 unsigned long i; 67 int err = 0; 68 69 for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) { 70 err = __add_section(zone, phys_start_pfn + i); 71 72 if (err) 73 break; 74 } 75 76 return err; 77 } 78 79 static void grow_zone_span(struct zone *zone, 80 unsigned long start_pfn, unsigned long end_pfn) 81 { 82 unsigned long old_zone_end_pfn; 83 84 zone_span_writelock(zone); 85 86 old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages; 87 if (start_pfn < zone->zone_start_pfn) 88 zone->zone_start_pfn = start_pfn; 89 90 if (end_pfn > old_zone_end_pfn) 91 zone->spanned_pages = end_pfn - zone->zone_start_pfn; 92 93 zone_span_writeunlock(zone); 94 } 95 96 static void grow_pgdat_span(struct pglist_data *pgdat, 97 unsigned long start_pfn, unsigned long end_pfn) 98 { 99 unsigned long old_pgdat_end_pfn = 100 pgdat->node_start_pfn + pgdat->node_spanned_pages; 101 102 if (start_pfn < pgdat->node_start_pfn) 103 pgdat->node_start_pfn = start_pfn; 104 105 if (end_pfn > old_pgdat_end_pfn) 106 pgdat->node_spanned_pages = end_pfn - pgdat->node_start_pfn; 107 } 108 109 int online_pages(unsigned long pfn, unsigned long nr_pages) 110 { 111 unsigned long i; 112 unsigned long flags; 113 unsigned long onlined_pages = 0; 114 struct zone *zone; 115 116 /* 117 * This doesn't need a lock to do pfn_to_page(). 118 * The section can't be removed here because of the 119 * memory_block->state_sem. 120 */ 121 zone = page_zone(pfn_to_page(pfn)); 122 pgdat_resize_lock(zone->zone_pgdat, &flags); 123 grow_zone_span(zone, pfn, pfn + nr_pages); 124 grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages); 125 pgdat_resize_unlock(zone->zone_pgdat, &flags); 126 127 for (i = 0; i < nr_pages; i++) { 128 struct page *page = pfn_to_page(pfn + i); 129 online_page(page); 130 onlined_pages++; 131 } 132 zone->present_pages += onlined_pages; 133 134 setup_per_zone_pages_min(); 135 136 return 0; 137 } 138