blob: 239f5a720d38fbe781751d2e3cb422cf49509d7d [file] [log] [blame]
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001/*
2 * sparse memory mappings.
3 */
Andy Whitcroftd41dee32005-06-23 00:07:54 -07004#include <linux/mm.h>
5#include <linux/mmzone.h>
6#include <linux/bootmem.h>
Dave Hansen0b0acbe2005-10-29 18:16:55 -07007#include <linux/highmem.h>
Andy Whitcroftd41dee32005-06-23 00:07:54 -07008#include <linux/module.h>
Dave Hansen28ae55c2005-09-03 15:54:29 -07009#include <linux/spinlock.h>
Dave Hansen0b0acbe2005-10-29 18:16:55 -070010#include <linux/vmalloc.h>
Andy Whitcroftd41dee32005-06-23 00:07:54 -070011#include <asm/dma.h>
12
13/*
14 * Permanent SPARSEMEM data:
15 *
16 * 1) mem_section - memory sections, mem_map's for valid memory
17 */
Bob Picco3e347262005-09-03 15:54:28 -070018#ifdef CONFIG_SPARSEMEM_EXTREME
Bob Picco802f1922005-09-03 15:54:26 -070019struct mem_section *mem_section[NR_SECTION_ROOTS]
Ravikiran G Thirumalai22fc6ec2006-01-08 01:01:27 -080020 ____cacheline_internodealigned_in_smp;
Bob Picco3e347262005-09-03 15:54:28 -070021#else
22struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
Ravikiran G Thirumalai22fc6ec2006-01-08 01:01:27 -080023 ____cacheline_internodealigned_in_smp;
Bob Picco3e347262005-09-03 15:54:28 -070024#endif
25EXPORT_SYMBOL(mem_section);
26
Christoph Lameter89689ae2006-12-06 20:31:45 -080027#ifdef NODE_NOT_IN_PAGE_FLAGS
28/*
29 * If we did not store the node number in the page then we have to
30 * do a lookup in the section_to_node_table in order to find which
31 * node the page belongs to.
32 */
33#if MAX_NUMNODES <= 256
34static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
35#else
36static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
37#endif
38
Andy Whitcroft25ba77c2006-12-06 20:33:03 -080039int page_to_nid(struct page *page)
Christoph Lameter89689ae2006-12-06 20:31:45 -080040{
41 return section_to_node_table[page_to_section(page)];
42}
43EXPORT_SYMBOL(page_to_nid);
Andy Whitcroft85770ff2007-08-22 14:01:03 -070044
45static void set_section_nid(unsigned long section_nr, int nid)
46{
47 section_to_node_table[section_nr] = nid;
48}
49#else /* !NODE_NOT_IN_PAGE_FLAGS */
50static inline void set_section_nid(unsigned long section_nr, int nid)
51{
52}
Christoph Lameter89689ae2006-12-06 20:31:45 -080053#endif
54
Bob Picco3e347262005-09-03 15:54:28 -070055#ifdef CONFIG_SPARSEMEM_EXTREME
Sam Ravnborg577a32f2007-05-17 23:29:25 +020056static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
Bob Picco802f1922005-09-03 15:54:26 -070057{
Dave Hansen28ae55c2005-09-03 15:54:29 -070058 struct mem_section *section = NULL;
59 unsigned long array_size = SECTIONS_PER_ROOT *
60 sizeof(struct mem_section);
Bob Picco802f1922005-09-03 15:54:26 -070061
Mike Kravetz39d24e62006-05-15 09:44:13 -070062 if (slab_is_available())
Mike Kravetz46a66ee2006-05-01 12:16:09 -070063 section = kmalloc_node(array_size, GFP_KERNEL, nid);
64 else
65 section = alloc_bootmem_node(NODE_DATA(nid), array_size);
Bob Picco3e347262005-09-03 15:54:28 -070066
Dave Hansen28ae55c2005-09-03 15:54:29 -070067 if (section)
68 memset(section, 0, array_size);
Bob Picco3e347262005-09-03 15:54:28 -070069
Dave Hansen28ae55c2005-09-03 15:54:29 -070070 return section;
Bob Picco802f1922005-09-03 15:54:26 -070071}
Dave Hansen28ae55c2005-09-03 15:54:29 -070072
Yasunori Gotoa3142c82007-05-08 00:23:07 -070073static int __meminit sparse_index_init(unsigned long section_nr, int nid)
Dave Hansen28ae55c2005-09-03 15:54:29 -070074{
Ingo Molnar34af9462006-06-27 02:53:55 -070075 static DEFINE_SPINLOCK(index_init_lock);
Dave Hansen28ae55c2005-09-03 15:54:29 -070076 unsigned long root = SECTION_NR_TO_ROOT(section_nr);
77 struct mem_section *section;
78 int ret = 0;
79
80 if (mem_section[root])
81 return -EEXIST;
82
83 section = sparse_index_alloc(nid);
84 /*
85 * This lock keeps two different sections from
86 * reallocating for the same index
87 */
88 spin_lock(&index_init_lock);
89
90 if (mem_section[root]) {
91 ret = -EEXIST;
92 goto out;
93 }
94
95 mem_section[root] = section;
96out:
97 spin_unlock(&index_init_lock);
98 return ret;
99}
100#else /* !SPARSEMEM_EXTREME */
101static inline int sparse_index_init(unsigned long section_nr, int nid)
102{
103 return 0;
104}
105#endif
106
Dave Hansen4ca644d2005-10-29 18:16:51 -0700107/*
108 * Although written for the SPARSEMEM_EXTREME case, this happens
109 * to also work for the flat array case becase
110 * NR_SECTION_ROOTS==NR_MEM_SECTIONS.
111 */
112int __section_nr(struct mem_section* ms)
113{
114 unsigned long root_nr;
115 struct mem_section* root;
116
Mike Kravetz12783b02006-05-20 15:00:05 -0700117 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
118 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
Dave Hansen4ca644d2005-10-29 18:16:51 -0700119 if (!root)
120 continue;
121
122 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
123 break;
124 }
125
126 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
127}
128
Andy Whitcroft30c253e2006-06-23 02:03:41 -0700129/*
130 * During early boot, before section_mem_map is used for an actual
131 * mem_map, we use section_mem_map to store the section's NUMA
132 * node. This keeps us from having to use another data structure. The
133 * node information is cleared just before we store the real mem_map.
134 */
135static inline unsigned long sparse_encode_early_nid(int nid)
136{
137 return (nid << SECTION_NID_SHIFT);
138}
139
140static inline int sparse_early_nid(struct mem_section *section)
141{
142 return (section->section_mem_map >> SECTION_NID_SHIFT);
143}
144
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700145/* Record a memory area against a node. */
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700146void __init memory_present(int nid, unsigned long start, unsigned long end)
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700147{
148 unsigned long pfn;
149
150 start &= PAGE_SECTION_MASK;
151 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
152 unsigned long section = pfn_to_section_nr(pfn);
Bob Picco802f1922005-09-03 15:54:26 -0700153 struct mem_section *ms;
154
155 sparse_index_init(section, nid);
Andy Whitcroft85770ff2007-08-22 14:01:03 -0700156 set_section_nid(section, nid);
Bob Picco802f1922005-09-03 15:54:26 -0700157
158 ms = __nr_to_section(section);
159 if (!ms->section_mem_map)
Andy Whitcroft30c253e2006-06-23 02:03:41 -0700160 ms->section_mem_map = sparse_encode_early_nid(nid) |
161 SECTION_MARKED_PRESENT;
Andy Whitcroftd41dee32005-06-23 00:07:54 -0700162 }
163}
164
165/*
166 * Only used by the i386 NUMA architecures, but relatively
167 * generic code.
168 */
169unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn,
170 unsigned long end_pfn)
171{
172 unsigned long pfn;
173 unsigned long nr_pages = 0;
174
175 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
176 if (nid != early_pfn_to_nid(pfn))
177 continue;
178
179 if (pfn_valid(pfn))
180 nr_pages += PAGES_PER_SECTION;
181 }
182
183 return nr_pages * sizeof(struct page);
184}
185
186/*
Andy Whitcroft29751f62005-06-23 00:08:00 -0700187 * Subtle, we encode the real pfn into the mem_map such that
188 * the identity pfn - section_mem_map will return the actual
189 * physical page frame number.
190 */
191static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
192{
193 return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
194}
195
196/*
197 * We need this if we ever free the mem_maps. While not implemented yet,
198 * this function is included for parity with its sibling.
199 */
200static __attribute((unused))
201struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
202{
203 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
204}
205
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700206static int __meminit sparse_init_one_section(struct mem_section *ms,
Andy Whitcroft29751f62005-06-23 00:08:00 -0700207 unsigned long pnum, struct page *mem_map)
208{
209 if (!valid_section(ms))
210 return -EINVAL;
211
Andy Whitcroft30c253e2006-06-23 02:03:41 -0700212 ms->section_mem_map &= ~SECTION_MAP_MASK;
Andy Whitcroft29751f62005-06-23 00:08:00 -0700213 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum);
214
215 return 1;
216}
217
Sam Ravnborgdec2e6b2007-07-22 11:12:44 +0200218__attribute__((weak)) __init
Zou Nan hai2e1c49d2007-06-01 00:46:28 -0700219void *alloc_bootmem_high_node(pg_data_t *pgdat, unsigned long size)
220{
221 return NULL;
222}
223
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700224static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
Andy Whitcroft29751f62005-06-23 00:08:00 -0700225{
226 struct page *map;
Bob Picco802f1922005-09-03 15:54:26 -0700227 struct mem_section *ms = __nr_to_section(pnum);
Andy Whitcroft30c253e2006-06-23 02:03:41 -0700228 int nid = sparse_early_nid(ms);
Andy Whitcroft29751f62005-06-23 00:08:00 -0700229
230 map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
231 if (map)
232 return map;
233
Zou Nan hai2e1c49d2007-06-01 00:46:28 -0700234 map = alloc_bootmem_high_node(NODE_DATA(nid),
235 sizeof(struct page) * PAGES_PER_SECTION);
236 if (map)
237 return map;
238
Andy Whitcroft29751f62005-06-23 00:08:00 -0700239 map = alloc_bootmem_node(NODE_DATA(nid),
240 sizeof(struct page) * PAGES_PER_SECTION);
241 if (map)
242 return map;
243
244 printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__);
Bob Picco802f1922005-09-03 15:54:26 -0700245 ms->section_mem_map = 0;
Andy Whitcroft29751f62005-06-23 00:08:00 -0700246 return NULL;
247}
248
Stephen Rothwell193faea2007-06-08 13:46:51 -0700249/*
250 * Allocate the accumulated non-linear sections, allocate a mem_map
251 * for each and record the physical to section mapping.
252 */
253void __init sparse_init(void)
254{
255 unsigned long pnum;
256 struct page *map;
257
258 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
259 if (!valid_section_nr(pnum))
260 continue;
261
262 map = sparse_early_mem_map_alloc(pnum);
263 if (!map)
264 continue;
265 sparse_init_one_section(__nr_to_section(pnum), pnum, map);
266 }
267}
268
269#ifdef CONFIG_MEMORY_HOTPLUG
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700270static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
271{
272 struct page *page, *ret;
273 unsigned long memmap_size = sizeof(struct page) * nr_pages;
274
Yasunori Gotof2d0aa52006-10-28 10:38:32 -0700275 page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700276 if (page)
277 goto got_map_page;
278
279 ret = vmalloc(memmap_size);
280 if (ret)
281 goto got_map_ptr;
282
283 return NULL;
284got_map_page:
285 ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
286got_map_ptr:
287 memset(ret, 0, memmap_size);
288
289 return ret;
290}
291
292static int vaddr_in_vmalloc_area(void *addr)
293{
294 if (addr >= (void *)VMALLOC_START &&
295 addr < (void *)VMALLOC_END)
296 return 1;
297 return 0;
298}
299
300static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
301{
302 if (vaddr_in_vmalloc_area(memmap))
303 vfree(memmap);
304 else
305 free_pages((unsigned long)memmap,
306 get_order(sizeof(struct page) * nr_pages));
307}
308
Andy Whitcroft29751f62005-06-23 00:08:00 -0700309/*
Andy Whitcroft29751f62005-06-23 00:08:00 -0700310 * returns the number of sections whose mem_maps were properly
311 * set. If this is <=0, then that means that the passed-in
312 * map was not consumed and must be freed.
313 */
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700314int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
315 int nr_pages)
Andy Whitcroft29751f62005-06-23 00:08:00 -0700316{
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700317 unsigned long section_nr = pfn_to_section_nr(start_pfn);
318 struct pglist_data *pgdat = zone->zone_pgdat;
319 struct mem_section *ms;
320 struct page *memmap;
321 unsigned long flags;
322 int ret;
Andy Whitcroft29751f62005-06-23 00:08:00 -0700323
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700324 /*
325 * no locking for this, because it does its own
326 * plus, it does a kmalloc
327 */
328 sparse_index_init(section_nr, pgdat->node_id);
329 memmap = __kmalloc_section_memmap(nr_pages);
Andy Whitcroft29751f62005-06-23 00:08:00 -0700330
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700331 pgdat_resize_lock(pgdat, &flags);
332
333 ms = __pfn_to_section(start_pfn);
334 if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
335 ret = -EEXIST;
336 goto out;
337 }
Andy Whitcroft29751f62005-06-23 00:08:00 -0700338 ms->section_mem_map |= SECTION_MARKED_PRESENT;
339
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700340 ret = sparse_init_one_section(ms, section_nr, memmap);
341
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700342out:
343 pgdat_resize_unlock(pgdat, &flags);
Mike Kravetz46a66ee2006-05-01 12:16:09 -0700344 if (ret <= 0)
345 __kfree_section_memmap(memmap, nr_pages);
Dave Hansen0b0acbe2005-10-29 18:16:55 -0700346 return ret;
Andy Whitcroft29751f62005-06-23 00:08:00 -0700347}
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700348#endif