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Commit | Line | Data |
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d41dee36 AW |
1 | /* |
2 | * sparse memory mappings. | |
3 | */ | |
4 | #include <linux/config.h> | |
5 | #include <linux/mm.h> | |
6 | #include <linux/mmzone.h> | |
7 | #include <linux/bootmem.h> | |
0b0acbec | 8 | #include <linux/highmem.h> |
d41dee36 | 9 | #include <linux/module.h> |
28ae55c9 | 10 | #include <linux/spinlock.h> |
0b0acbec | 11 | #include <linux/vmalloc.h> |
d41dee36 AW |
12 | #include <asm/dma.h> |
13 | ||
14 | /* | |
15 | * Permanent SPARSEMEM data: | |
16 | * | |
17 | * 1) mem_section - memory sections, mem_map's for valid memory | |
18 | */ | |
3e347261 | 19 | #ifdef CONFIG_SPARSEMEM_EXTREME |
802f192e | 20 | struct mem_section *mem_section[NR_SECTION_ROOTS] |
22fc6ecc | 21 | ____cacheline_internodealigned_in_smp; |
3e347261 BP |
22 | #else |
23 | struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT] | |
22fc6ecc | 24 | ____cacheline_internodealigned_in_smp; |
3e347261 BP |
25 | #endif |
26 | EXPORT_SYMBOL(mem_section); | |
27 | ||
3e347261 | 28 | #ifdef CONFIG_SPARSEMEM_EXTREME |
28ae55c9 DH |
29 | static struct mem_section *sparse_index_alloc(int nid) |
30 | { | |
31 | struct mem_section *section = NULL; | |
32 | unsigned long array_size = SECTIONS_PER_ROOT * | |
33 | sizeof(struct mem_section); | |
34 | ||
39d24e64 | 35 | if (slab_is_available()) |
46a66eec MK |
36 | section = kmalloc_node(array_size, GFP_KERNEL, nid); |
37 | else | |
38 | section = alloc_bootmem_node(NODE_DATA(nid), array_size); | |
28ae55c9 DH |
39 | |
40 | if (section) | |
41 | memset(section, 0, array_size); | |
42 | ||
43 | return section; | |
3e347261 | 44 | } |
802f192e | 45 | |
28ae55c9 | 46 | static int sparse_index_init(unsigned long section_nr, int nid) |
802f192e | 47 | { |
28ae55c9 DH |
48 | static spinlock_t index_init_lock = SPIN_LOCK_UNLOCKED; |
49 | unsigned long root = SECTION_NR_TO_ROOT(section_nr); | |
50 | struct mem_section *section; | |
51 | int ret = 0; | |
802f192e BP |
52 | |
53 | if (mem_section[root]) | |
28ae55c9 | 54 | return -EEXIST; |
3e347261 | 55 | |
28ae55c9 DH |
56 | section = sparse_index_alloc(nid); |
57 | /* | |
58 | * This lock keeps two different sections from | |
59 | * reallocating for the same index | |
60 | */ | |
61 | spin_lock(&index_init_lock); | |
3e347261 | 62 | |
28ae55c9 DH |
63 | if (mem_section[root]) { |
64 | ret = -EEXIST; | |
65 | goto out; | |
66 | } | |
67 | ||
68 | mem_section[root] = section; | |
69 | out: | |
70 | spin_unlock(&index_init_lock); | |
71 | return ret; | |
72 | } | |
73 | #else /* !SPARSEMEM_EXTREME */ | |
74 | static inline int sparse_index_init(unsigned long section_nr, int nid) | |
75 | { | |
76 | return 0; | |
802f192e | 77 | } |
28ae55c9 DH |
78 | #endif |
79 | ||
4ca644d9 DH |
80 | /* |
81 | * Although written for the SPARSEMEM_EXTREME case, this happens | |
82 | * to also work for the flat array case becase | |
83 | * NR_SECTION_ROOTS==NR_MEM_SECTIONS. | |
84 | */ | |
85 | int __section_nr(struct mem_section* ms) | |
86 | { | |
87 | unsigned long root_nr; | |
88 | struct mem_section* root; | |
89 | ||
12783b00 MK |
90 | for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) { |
91 | root = __nr_to_section(root_nr * SECTIONS_PER_ROOT); | |
4ca644d9 DH |
92 | if (!root) |
93 | continue; | |
94 | ||
95 | if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT))) | |
96 | break; | |
97 | } | |
98 | ||
99 | return (root_nr * SECTIONS_PER_ROOT) + (ms - root); | |
100 | } | |
101 | ||
30c253e6 AW |
102 | /* |
103 | * During early boot, before section_mem_map is used for an actual | |
104 | * mem_map, we use section_mem_map to store the section's NUMA | |
105 | * node. This keeps us from having to use another data structure. The | |
106 | * node information is cleared just before we store the real mem_map. | |
107 | */ | |
108 | static inline unsigned long sparse_encode_early_nid(int nid) | |
109 | { | |
110 | return (nid << SECTION_NID_SHIFT); | |
111 | } | |
112 | ||
113 | static inline int sparse_early_nid(struct mem_section *section) | |
114 | { | |
115 | return (section->section_mem_map >> SECTION_NID_SHIFT); | |
116 | } | |
117 | ||
d41dee36 AW |
118 | /* Record a memory area against a node. */ |
119 | void memory_present(int nid, unsigned long start, unsigned long end) | |
120 | { | |
121 | unsigned long pfn; | |
122 | ||
123 | start &= PAGE_SECTION_MASK; | |
124 | for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) { | |
125 | unsigned long section = pfn_to_section_nr(pfn); | |
802f192e BP |
126 | struct mem_section *ms; |
127 | ||
128 | sparse_index_init(section, nid); | |
129 | ||
130 | ms = __nr_to_section(section); | |
131 | if (!ms->section_mem_map) | |
30c253e6 AW |
132 | ms->section_mem_map = sparse_encode_early_nid(nid) | |
133 | SECTION_MARKED_PRESENT; | |
d41dee36 AW |
134 | } |
135 | } | |
136 | ||
137 | /* | |
138 | * Only used by the i386 NUMA architecures, but relatively | |
139 | * generic code. | |
140 | */ | |
141 | unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn, | |
142 | unsigned long end_pfn) | |
143 | { | |
144 | unsigned long pfn; | |
145 | unsigned long nr_pages = 0; | |
146 | ||
147 | for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { | |
148 | if (nid != early_pfn_to_nid(pfn)) | |
149 | continue; | |
150 | ||
151 | if (pfn_valid(pfn)) | |
152 | nr_pages += PAGES_PER_SECTION; | |
153 | } | |
154 | ||
155 | return nr_pages * sizeof(struct page); | |
156 | } | |
157 | ||
29751f69 AW |
158 | /* |
159 | * Subtle, we encode the real pfn into the mem_map such that | |
160 | * the identity pfn - section_mem_map will return the actual | |
161 | * physical page frame number. | |
162 | */ | |
163 | static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum) | |
164 | { | |
165 | return (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); | |
166 | } | |
167 | ||
168 | /* | |
169 | * We need this if we ever free the mem_maps. While not implemented yet, | |
170 | * this function is included for parity with its sibling. | |
171 | */ | |
172 | static __attribute((unused)) | |
173 | struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum) | |
174 | { | |
175 | return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum); | |
176 | } | |
177 | ||
178 | static int sparse_init_one_section(struct mem_section *ms, | |
179 | unsigned long pnum, struct page *mem_map) | |
180 | { | |
181 | if (!valid_section(ms)) | |
182 | return -EINVAL; | |
183 | ||
30c253e6 | 184 | ms->section_mem_map &= ~SECTION_MAP_MASK; |
29751f69 AW |
185 | ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum); |
186 | ||
187 | return 1; | |
188 | } | |
189 | ||
190 | static struct page *sparse_early_mem_map_alloc(unsigned long pnum) | |
191 | { | |
192 | struct page *map; | |
802f192e | 193 | struct mem_section *ms = __nr_to_section(pnum); |
30c253e6 | 194 | int nid = sparse_early_nid(ms); |
29751f69 AW |
195 | |
196 | map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION); | |
197 | if (map) | |
198 | return map; | |
199 | ||
200 | map = alloc_bootmem_node(NODE_DATA(nid), | |
201 | sizeof(struct page) * PAGES_PER_SECTION); | |
202 | if (map) | |
203 | return map; | |
204 | ||
205 | printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__); | |
802f192e | 206 | ms->section_mem_map = 0; |
29751f69 AW |
207 | return NULL; |
208 | } | |
209 | ||
0b0acbec DH |
210 | static struct page *__kmalloc_section_memmap(unsigned long nr_pages) |
211 | { | |
212 | struct page *page, *ret; | |
213 | unsigned long memmap_size = sizeof(struct page) * nr_pages; | |
214 | ||
215 | page = alloc_pages(GFP_KERNEL, get_order(memmap_size)); | |
216 | if (page) | |
217 | goto got_map_page; | |
218 | ||
219 | ret = vmalloc(memmap_size); | |
220 | if (ret) | |
221 | goto got_map_ptr; | |
222 | ||
223 | return NULL; | |
224 | got_map_page: | |
225 | ret = (struct page *)pfn_to_kaddr(page_to_pfn(page)); | |
226 | got_map_ptr: | |
227 | memset(ret, 0, memmap_size); | |
228 | ||
229 | return ret; | |
230 | } | |
231 | ||
232 | static int vaddr_in_vmalloc_area(void *addr) | |
233 | { | |
234 | if (addr >= (void *)VMALLOC_START && | |
235 | addr < (void *)VMALLOC_END) | |
236 | return 1; | |
237 | return 0; | |
238 | } | |
239 | ||
240 | static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) | |
241 | { | |
242 | if (vaddr_in_vmalloc_area(memmap)) | |
243 | vfree(memmap); | |
244 | else | |
245 | free_pages((unsigned long)memmap, | |
246 | get_order(sizeof(struct page) * nr_pages)); | |
247 | } | |
248 | ||
d41dee36 AW |
249 | /* |
250 | * Allocate the accumulated non-linear sections, allocate a mem_map | |
251 | * for each and record the physical to section mapping. | |
252 | */ | |
253 | void sparse_init(void) | |
254 | { | |
255 | unsigned long pnum; | |
256 | struct page *map; | |
d41dee36 AW |
257 | |
258 | for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { | |
29751f69 | 259 | if (!valid_section_nr(pnum)) |
d41dee36 AW |
260 | continue; |
261 | ||
29751f69 | 262 | map = sparse_early_mem_map_alloc(pnum); |
802f192e BP |
263 | if (!map) |
264 | continue; | |
265 | sparse_init_one_section(__nr_to_section(pnum), pnum, map); | |
d41dee36 AW |
266 | } |
267 | } | |
29751f69 AW |
268 | |
269 | /* | |
270 | * returns the number of sections whose mem_maps were properly | |
271 | * set. If this is <=0, then that means that the passed-in | |
272 | * map was not consumed and must be freed. | |
273 | */ | |
0b0acbec DH |
274 | int sparse_add_one_section(struct zone *zone, unsigned long start_pfn, |
275 | int nr_pages) | |
29751f69 | 276 | { |
0b0acbec DH |
277 | unsigned long section_nr = pfn_to_section_nr(start_pfn); |
278 | struct pglist_data *pgdat = zone->zone_pgdat; | |
279 | struct mem_section *ms; | |
280 | struct page *memmap; | |
281 | unsigned long flags; | |
282 | int ret; | |
29751f69 | 283 | |
0b0acbec DH |
284 | /* |
285 | * no locking for this, because it does its own | |
286 | * plus, it does a kmalloc | |
287 | */ | |
288 | sparse_index_init(section_nr, pgdat->node_id); | |
289 | memmap = __kmalloc_section_memmap(nr_pages); | |
290 | ||
291 | pgdat_resize_lock(pgdat, &flags); | |
29751f69 | 292 | |
0b0acbec DH |
293 | ms = __pfn_to_section(start_pfn); |
294 | if (ms->section_mem_map & SECTION_MARKED_PRESENT) { | |
295 | ret = -EEXIST; | |
296 | goto out; | |
297 | } | |
29751f69 AW |
298 | ms->section_mem_map |= SECTION_MARKED_PRESENT; |
299 | ||
0b0acbec DH |
300 | ret = sparse_init_one_section(ms, section_nr, memmap); |
301 | ||
0b0acbec DH |
302 | out: |
303 | pgdat_resize_unlock(pgdat, &flags); | |
46a66eec MK |
304 | if (ret <= 0) |
305 | __kfree_section_memmap(memmap, nr_pages); | |
0b0acbec | 306 | return ret; |
29751f69 | 307 | } |