[PATCH] spanned_pages is not updated at a case of memory hot-add
[linux-2.6.git] / 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         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                 /* We want to keep adding the rest of the
73                  * sections if the first ones already exist
74                  */
75                 if (err && (err != -EEXIST))
76                         break;
77         }
78
79         return err;
80 }
81 EXPORT_SYMBOL_GPL(__add_pages);
82
83 static void grow_zone_span(struct zone *zone,
84                 unsigned long start_pfn, unsigned long end_pfn)
85 {
86         unsigned long old_zone_end_pfn;
87
88         zone_span_writelock(zone);
89
90         old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
91         if (start_pfn < zone->zone_start_pfn)
92                 zone->zone_start_pfn = start_pfn;
93
94         zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
95                                 zone->zone_start_pfn;
96
97         zone_span_writeunlock(zone);
98 }
99
100 static void grow_pgdat_span(struct pglist_data *pgdat,
101                 unsigned long start_pfn, unsigned long end_pfn)
102 {
103         unsigned long old_pgdat_end_pfn =
104                 pgdat->node_start_pfn + pgdat->node_spanned_pages;
105
106         if (start_pfn < pgdat->node_start_pfn)
107                 pgdat->node_start_pfn = start_pfn;
108
109         pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
110                                         pgdat->node_start_pfn;
111 }
112
113 int online_pages(unsigned long pfn, unsigned long nr_pages)
114 {
115         unsigned long i;
116         unsigned long flags;
117         unsigned long onlined_pages = 0;
118         struct zone *zone;
119
120         /*
121          * This doesn't need a lock to do pfn_to_page().
122          * The section can't be removed here because of the
123          * memory_block->state_sem.
124          */
125         zone = page_zone(pfn_to_page(pfn));
126         pgdat_resize_lock(zone->zone_pgdat, &flags);
127         grow_zone_span(zone, pfn, pfn + nr_pages);
128         grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages);
129         pgdat_resize_unlock(zone->zone_pgdat, &flags);
130
131         for (i = 0; i < nr_pages; i++) {
132                 struct page *page = pfn_to_page(pfn + i);
133                 online_page(page);
134                 onlined_pages++;
135         }
136         zone->present_pages += onlined_pages;
137         zone->zone_pgdat->node_present_pages += onlined_pages;
138
139         setup_per_zone_pages_min();
140
141         return 0;
142 }