Merge branch 'master'
[linux-2.6] / mm / memory_hotplug.c
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 }