]>
Commit | Line | Data |
---|---|---|
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 | ||
90 | for (root_nr = 0; | |
91 | root_nr < NR_MEM_SECTIONS; | |
92 | root_nr += SECTIONS_PER_ROOT) { | |
93 | root = __nr_to_section(root_nr); | |
94 | ||
95 | if (!root) | |
96 | continue; | |
97 | ||
98 | if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT))) | |
99 | break; | |
100 | } | |
101 | ||
102 | return (root_nr * SECTIONS_PER_ROOT) + (ms - root); | |
103 | } | |
104 | ||
d41dee36 AW |
105 | /* Record a memory area against a node. */ |
106 | void memory_present(int nid, unsigned long start, unsigned long end) | |
107 | { | |
108 | unsigned long pfn; | |
109 | ||
110 | start &= PAGE_SECTION_MASK; | |
111 | for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) { | |
112 | unsigned long section = pfn_to_section_nr(pfn); | |
802f192e BP |
113 | struct mem_section *ms; |
114 | ||
115 | sparse_index_init(section, nid); | |
116 | ||
117 | ms = __nr_to_section(section); | |
118 | if (!ms->section_mem_map) | |
119 | ms->section_mem_map = SECTION_MARKED_PRESENT; | |
d41dee36 AW |
120 | } |
121 | } | |
122 | ||
123 | /* | |
124 | * Only used by the i386 NUMA architecures, but relatively | |
125 | * generic code. | |
126 | */ | |
127 | unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn, | |
128 | unsigned long end_pfn) | |
129 | { | |
130 | unsigned long pfn; | |
131 | unsigned long nr_pages = 0; | |
132 | ||
133 | for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { | |
134 | if (nid != early_pfn_to_nid(pfn)) | |
135 | continue; | |
136 | ||
137 | if (pfn_valid(pfn)) | |
138 | nr_pages += PAGES_PER_SECTION; | |
139 | } | |
140 | ||
141 | return nr_pages * sizeof(struct page); | |
142 | } | |
143 | ||
29751f69 AW |
144 | /* |
145 | * Subtle, we encode the real pfn into the mem_map such that | |
146 | * the identity pfn - section_mem_map will return the actual | |
147 | * physical page frame number. | |
148 | */ | |
149 | static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum) | |
150 | { | |
151 | return (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); | |
152 | } | |
153 | ||
154 | /* | |
155 | * We need this if we ever free the mem_maps. While not implemented yet, | |
156 | * this function is included for parity with its sibling. | |
157 | */ | |
158 | static __attribute((unused)) | |
159 | struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum) | |
160 | { | |
161 | return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum); | |
162 | } | |
163 | ||
164 | static int sparse_init_one_section(struct mem_section *ms, | |
165 | unsigned long pnum, struct page *mem_map) | |
166 | { | |
167 | if (!valid_section(ms)) | |
168 | return -EINVAL; | |
169 | ||
170 | ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum); | |
171 | ||
172 | return 1; | |
173 | } | |
174 | ||
175 | static struct page *sparse_early_mem_map_alloc(unsigned long pnum) | |
176 | { | |
177 | struct page *map; | |
178 | int nid = early_pfn_to_nid(section_nr_to_pfn(pnum)); | |
802f192e | 179 | struct mem_section *ms = __nr_to_section(pnum); |
29751f69 AW |
180 | |
181 | map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION); | |
182 | if (map) | |
183 | return map; | |
184 | ||
185 | map = alloc_bootmem_node(NODE_DATA(nid), | |
186 | sizeof(struct page) * PAGES_PER_SECTION); | |
187 | if (map) | |
188 | return map; | |
189 | ||
190 | printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__); | |
802f192e | 191 | ms->section_mem_map = 0; |
29751f69 AW |
192 | return NULL; |
193 | } | |
194 | ||
0b0acbec DH |
195 | static struct page *__kmalloc_section_memmap(unsigned long nr_pages) |
196 | { | |
197 | struct page *page, *ret; | |
198 | unsigned long memmap_size = sizeof(struct page) * nr_pages; | |
199 | ||
200 | page = alloc_pages(GFP_KERNEL, get_order(memmap_size)); | |
201 | if (page) | |
202 | goto got_map_page; | |
203 | ||
204 | ret = vmalloc(memmap_size); | |
205 | if (ret) | |
206 | goto got_map_ptr; | |
207 | ||
208 | return NULL; | |
209 | got_map_page: | |
210 | ret = (struct page *)pfn_to_kaddr(page_to_pfn(page)); | |
211 | got_map_ptr: | |
212 | memset(ret, 0, memmap_size); | |
213 | ||
214 | return ret; | |
215 | } | |
216 | ||
217 | static int vaddr_in_vmalloc_area(void *addr) | |
218 | { | |
219 | if (addr >= (void *)VMALLOC_START && | |
220 | addr < (void *)VMALLOC_END) | |
221 | return 1; | |
222 | return 0; | |
223 | } | |
224 | ||
225 | static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) | |
226 | { | |
227 | if (vaddr_in_vmalloc_area(memmap)) | |
228 | vfree(memmap); | |
229 | else | |
230 | free_pages((unsigned long)memmap, | |
231 | get_order(sizeof(struct page) * nr_pages)); | |
232 | } | |
233 | ||
d41dee36 AW |
234 | /* |
235 | * Allocate the accumulated non-linear sections, allocate a mem_map | |
236 | * for each and record the physical to section mapping. | |
237 | */ | |
238 | void sparse_init(void) | |
239 | { | |
240 | unsigned long pnum; | |
241 | struct page *map; | |
d41dee36 AW |
242 | |
243 | for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { | |
29751f69 | 244 | if (!valid_section_nr(pnum)) |
d41dee36 AW |
245 | continue; |
246 | ||
29751f69 | 247 | map = sparse_early_mem_map_alloc(pnum); |
802f192e BP |
248 | if (!map) |
249 | continue; | |
250 | sparse_init_one_section(__nr_to_section(pnum), pnum, map); | |
d41dee36 AW |
251 | } |
252 | } | |
29751f69 AW |
253 | |
254 | /* | |
255 | * returns the number of sections whose mem_maps were properly | |
256 | * set. If this is <=0, then that means that the passed-in | |
257 | * map was not consumed and must be freed. | |
258 | */ | |
0b0acbec DH |
259 | int sparse_add_one_section(struct zone *zone, unsigned long start_pfn, |
260 | int nr_pages) | |
29751f69 | 261 | { |
0b0acbec DH |
262 | unsigned long section_nr = pfn_to_section_nr(start_pfn); |
263 | struct pglist_data *pgdat = zone->zone_pgdat; | |
264 | struct mem_section *ms; | |
265 | struct page *memmap; | |
266 | unsigned long flags; | |
267 | int ret; | |
29751f69 | 268 | |
0b0acbec DH |
269 | /* |
270 | * no locking for this, because it does its own | |
271 | * plus, it does a kmalloc | |
272 | */ | |
273 | sparse_index_init(section_nr, pgdat->node_id); | |
274 | memmap = __kmalloc_section_memmap(nr_pages); | |
275 | ||
276 | pgdat_resize_lock(pgdat, &flags); | |
29751f69 | 277 | |
0b0acbec DH |
278 | ms = __pfn_to_section(start_pfn); |
279 | if (ms->section_mem_map & SECTION_MARKED_PRESENT) { | |
280 | ret = -EEXIST; | |
281 | goto out; | |
282 | } | |
29751f69 AW |
283 | ms->section_mem_map |= SECTION_MARKED_PRESENT; |
284 | ||
0b0acbec DH |
285 | ret = sparse_init_one_section(ms, section_nr, memmap); |
286 | ||
0b0acbec DH |
287 | out: |
288 | pgdat_resize_unlock(pgdat, &flags); | |
46a66eec MK |
289 | if (ret <= 0) |
290 | __kfree_section_memmap(memmap, nr_pages); | |
0b0acbec | 291 | return ret; |
29751f69 | 292 | } |