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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - mm/memory_hotplug.c
2 * linux/mm/memory_hotplug.c
7 #include <linux/stddef.h>
9 #include <linux/swap.h>
10 #include <linux/interrupt.h>
11 #include <linux/pagemap.h>
12 #include <linux/bootmem.h>
13 #include <linux/compiler.h>
14 #include <linux/module.h>
15 #include <linux/pagevec.h>
16 #include <linux/writeback.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 #include <linux/ioport.h>
25 #include <linux/cpuset.h>
27 #include <asm/tlbflush.h>
29 extern void zonetable_add(struct zone
*zone
, int nid
, int zid
, unsigned long pfn
,
31 static int __add_zone(struct zone
*zone
, unsigned long phys_start_pfn
)
33 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
34 int nr_pages
= PAGES_PER_SECTION
;
35 int nid
= pgdat
->node_id
;
38 zone_type
= zone
- pgdat
->node_zones
;
39 if (!populated_zone(zone
)) {
41 ret
= init_currently_empty_zone(zone
, phys_start_pfn
, nr_pages
);
45 memmap_init_zone(nr_pages
, nid
, zone_type
, phys_start_pfn
);
46 zonetable_add(zone
, nid
, zone_type
, phys_start_pfn
, nr_pages
);
50 extern int sparse_add_one_section(struct zone
*zone
, unsigned long start_pfn
,
52 static int __add_section(struct zone
*zone
, unsigned long phys_start_pfn
)
54 int nr_pages
= PAGES_PER_SECTION
;
57 if (pfn_valid(phys_start_pfn
))
60 ret
= sparse_add_one_section(zone
, phys_start_pfn
, nr_pages
);
65 ret
= __add_zone(zone
, phys_start_pfn
);
70 return register_new_memory(__pfn_to_section(phys_start_pfn
));
74 * Reasonably generic function for adding memory. It is
75 * expected that archs that support memory hotplug will
76 * call this function after deciding the zone to which to
79 int __add_pages(struct zone
*zone
, unsigned long phys_start_pfn
,
80 unsigned long nr_pages
)
84 int start_sec
, end_sec
;
85 /* during initialize mem_map, align hot-added range to section */
86 start_sec
= pfn_to_section_nr(phys_start_pfn
);
87 end_sec
= pfn_to_section_nr(phys_start_pfn
+ nr_pages
- 1);
89 for (i
= start_sec
; i
<= end_sec
; i
++) {
90 err
= __add_section(zone
, i
<< PFN_SECTION_SHIFT
);
93 * EEXIST is finally dealed with by ioresource collision
94 * check. see add_memory() => register_memory_resource()
95 * Warning will be printed if there is collision.
97 if (err
&& (err
!= -EEXIST
))
104 EXPORT_SYMBOL_GPL(__add_pages
);
106 static void grow_zone_span(struct zone
*zone
,
107 unsigned long start_pfn
, unsigned long end_pfn
)
109 unsigned long old_zone_end_pfn
;
111 zone_span_writelock(zone
);
113 old_zone_end_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
114 if (start_pfn
< zone
->zone_start_pfn
)
115 zone
->zone_start_pfn
= start_pfn
;
117 zone
->spanned_pages
= max(old_zone_end_pfn
, end_pfn
) -
118 zone
->zone_start_pfn
;
120 zone_span_writeunlock(zone
);
123 static void grow_pgdat_span(struct pglist_data
*pgdat
,
124 unsigned long start_pfn
, unsigned long end_pfn
)
126 unsigned long old_pgdat_end_pfn
=
127 pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
129 if (start_pfn
< pgdat
->node_start_pfn
)
130 pgdat
->node_start_pfn
= start_pfn
;
132 pgdat
->node_spanned_pages
= max(old_pgdat_end_pfn
, end_pfn
) -
133 pgdat
->node_start_pfn
;
136 int online_pages(unsigned long pfn
, unsigned long nr_pages
)
140 unsigned long onlined_pages
= 0;
143 unsigned long start_pfn
;
145 int need_zonelists_rebuild
= 0;
148 * This doesn't need a lock to do pfn_to_page().
149 * The section can't be removed here because of the
150 * memory_block->state_sem.
152 zone
= page_zone(pfn_to_page(pfn
));
153 pgdat_resize_lock(zone
->zone_pgdat
, &flags
);
154 grow_zone_span(zone
, pfn
, pfn
+ nr_pages
);
155 grow_pgdat_span(zone
->zone_pgdat
, pfn
, pfn
+ nr_pages
);
156 pgdat_resize_unlock(zone
->zone_pgdat
, &flags
);
159 * If this zone is not populated, then it is not in zonelist.
160 * This means the page allocator ignores this zone.
161 * So, zonelist must be updated after online.
163 if (!populated_zone(zone
))
164 need_zonelists_rebuild
= 1;
166 res
.start
= (u64
)pfn
<< PAGE_SHIFT
;
167 res
.end
= res
.start
+ ((u64
)nr_pages
<< PAGE_SHIFT
) - 1;
168 res
.flags
= IORESOURCE_MEM
; /* we just need system ram */
169 section_end
= res
.end
;
171 while ((res
.start
< res
.end
) && (find_next_system_ram(&res
) >= 0)) {
172 start_pfn
= (unsigned long)(res
.start
>> PAGE_SHIFT
);
173 nr_pages
= (unsigned long)
174 ((res
.end
+ 1 - res
.start
) >> PAGE_SHIFT
);
176 if (PageReserved(pfn_to_page(start_pfn
))) {
177 /* this region's page is not onlined now */
178 for (i
= 0; i
< nr_pages
; i
++) {
179 struct page
*page
= pfn_to_page(start_pfn
+ i
);
185 res
.start
= res
.end
+ 1;
186 res
.end
= section_end
;
188 zone
->present_pages
+= onlined_pages
;
189 zone
->zone_pgdat
->node_present_pages
+= onlined_pages
;
191 setup_per_zone_pages_min();
193 if (need_zonelists_rebuild
)
194 build_all_zonelists();
195 vm_total_pages
= nr_free_pagecache_pages();
196 writeback_set_ratelimit();
200 static pg_data_t
*hotadd_new_pgdat(int nid
, u64 start
)
202 struct pglist_data
*pgdat
;
203 unsigned long zones_size
[MAX_NR_ZONES
] = {0};
204 unsigned long zholes_size
[MAX_NR_ZONES
] = {0};
205 unsigned long start_pfn
= start
>> PAGE_SHIFT
;
207 pgdat
= arch_alloc_nodedata(nid
);
211 arch_refresh_nodedata(nid
, pgdat
);
213 /* we can use NODE_DATA(nid) from here */
215 /* init node's zones as empty zones, we don't have any present pages.*/
216 free_area_init_node(nid
, pgdat
, zones_size
, start_pfn
, zholes_size
);
221 static void rollback_node_hotadd(int nid
, pg_data_t
*pgdat
)
223 arch_refresh_nodedata(nid
, NULL
);
224 arch_free_nodedata(pgdat
);
228 /* add this memory to iomem resource */
229 static struct resource
*register_memory_resource(u64 start
, u64 size
)
231 struct resource
*res
;
232 res
= kzalloc(sizeof(struct resource
), GFP_KERNEL
);
235 res
->name
= "System RAM";
237 res
->end
= start
+ size
- 1;
238 res
->flags
= IORESOURCE_MEM
;
239 if (request_resource(&iomem_resource
, res
) < 0) {
240 printk("System RAM resource %llx - %llx cannot be added\n",
241 (unsigned long long)res
->start
, (unsigned long long)res
->end
);
248 static void release_memory_resource(struct resource
*res
)
252 release_resource(res
);
259 int add_memory(int nid
, u64 start
, u64 size
)
261 pg_data_t
*pgdat
= NULL
;
263 struct resource
*res
;
266 res
= register_memory_resource(start
, size
);
270 if (!node_online(nid
)) {
271 pgdat
= hotadd_new_pgdat(nid
, start
);
275 ret
= kswapd_run(nid
);
280 /* call arch's memory hotadd */
281 ret
= arch_add_memory(nid
, start
, size
);
286 /* we online node here. we can't roll back from here. */
287 node_set_online(nid
);
289 cpuset_track_online_nodes();
292 ret
= register_one_node(nid
);
294 * If sysfs file of new node can't create, cpu on the node
295 * can't be hot-added. There is no rollback way now.
296 * So, check by BUG_ON() to catch it reluctantly..
303 /* rollback pgdat allocation and others */
305 rollback_node_hotadd(nid
, pgdat
);
307 release_memory_resource(res
);
311 EXPORT_SYMBOL_GPL(add_memory
);