1#include <linux/mm.h>
2#include <linux/mmzone.h>
3#include <linux/bootmem.h>
4#include <linux/page_ext.h>
5#include <linux/memory.h>
6#include <linux/vmalloc.h>
7#include <linux/kmemleak.h>
8#include <linux/page_owner.h>
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53
54static struct page_ext_operations *page_ext_ops[] = {
55 &debug_guardpage_ops,
56#ifdef CONFIG_PAGE_POISONING
57 &page_poisoning_ops,
58#endif
59#ifdef CONFIG_PAGE_OWNER
60 &page_owner_ops,
61#endif
62};
63
64static unsigned long total_usage;
65
66static bool __init invoke_need_callbacks(void)
67{
68 int i;
69 int entries = ARRAY_SIZE(page_ext_ops);
70
71 for (i = 0; i < entries; i++) {
72 if (page_ext_ops[i]->need && page_ext_ops[i]->need())
73 return true;
74 }
75
76 return false;
77}
78
79static void __init invoke_init_callbacks(void)
80{
81 int i;
82 int entries = ARRAY_SIZE(page_ext_ops);
83
84 for (i = 0; i < entries; i++) {
85 if (page_ext_ops[i]->init)
86 page_ext_ops[i]->init();
87 }
88}
89
90#if !defined(CONFIG_SPARSEMEM)
91
92
93void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
94{
95 pgdat->node_page_ext = NULL;
96}
97
98struct page_ext *lookup_page_ext(struct page *page)
99{
100 unsigned long pfn = page_to_pfn(page);
101 unsigned long offset;
102 struct page_ext *base;
103
104 base = NODE_DATA(page_to_nid(page))->node_page_ext;
105#ifdef CONFIG_DEBUG_VM
106
107
108
109
110
111
112 if (unlikely(!base))
113 return NULL;
114#endif
115 offset = pfn - round_down(node_start_pfn(page_to_nid(page)),
116 MAX_ORDER_NR_PAGES);
117 return base + offset;
118}
119
120static int __init alloc_node_page_ext(int nid)
121{
122 struct page_ext *base;
123 unsigned long table_size;
124 unsigned long nr_pages;
125
126 nr_pages = NODE_DATA(nid)->node_spanned_pages;
127 if (!nr_pages)
128 return 0;
129
130
131
132
133
134
135 if (!IS_ALIGNED(node_start_pfn(nid), MAX_ORDER_NR_PAGES) ||
136 !IS_ALIGNED(node_end_pfn(nid), MAX_ORDER_NR_PAGES))
137 nr_pages += MAX_ORDER_NR_PAGES;
138
139 table_size = sizeof(struct page_ext) * nr_pages;
140
141 base = memblock_virt_alloc_try_nid_nopanic(
142 table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
143 BOOTMEM_ALLOC_ACCESSIBLE, nid);
144 if (!base)
145 return -ENOMEM;
146 NODE_DATA(nid)->node_page_ext = base;
147 total_usage += table_size;
148 return 0;
149}
150
151void __init page_ext_init_flatmem(void)
152{
153
154 int nid, fail;
155
156 if (!invoke_need_callbacks())
157 return;
158
159 for_each_online_node(nid) {
160 fail = alloc_node_page_ext(nid);
161 if (fail)
162 goto fail;
163 }
164 pr_info("allocated %ld bytes of page_ext\n", total_usage);
165 invoke_init_callbacks();
166 return;
167
168fail:
169 pr_crit("allocation of page_ext failed.\n");
170 panic("Out of memory");
171}
172
173#else
174
175struct page_ext *lookup_page_ext(struct page *page)
176{
177 unsigned long pfn = page_to_pfn(page);
178 struct mem_section *section = __pfn_to_section(pfn);
179#ifdef CONFIG_DEBUG_VM
180
181
182
183
184
185
186 if (!section->page_ext)
187 return NULL;
188#endif
189 return section->page_ext + pfn;
190}
191
192static void *__meminit alloc_page_ext(size_t size, int nid)
193{
194 gfp_t flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN;
195 void *addr = NULL;
196
197 addr = alloc_pages_exact_nid(nid, size, flags);
198 if (addr) {
199 kmemleak_alloc(addr, size, 1, flags);
200 return addr;
201 }
202
203 if (node_state(nid, N_HIGH_MEMORY))
204 addr = vzalloc_node(size, nid);
205 else
206 addr = vzalloc(size);
207
208 return addr;
209}
210
211static int __meminit init_section_page_ext(unsigned long pfn, int nid)
212{
213 struct mem_section *section;
214 struct page_ext *base;
215 unsigned long table_size;
216
217 section = __pfn_to_section(pfn);
218
219 if (section->page_ext)
220 return 0;
221
222 table_size = sizeof(struct page_ext) * PAGES_PER_SECTION;
223 base = alloc_page_ext(table_size, nid);
224
225
226
227
228
229
230 kmemleak_not_leak(base);
231
232 if (!base) {
233 pr_err("page ext allocation failure\n");
234 return -ENOMEM;
235 }
236
237
238
239
240
241 pfn &= PAGE_SECTION_MASK;
242 section->page_ext = base - pfn;
243 total_usage += table_size;
244 return 0;
245}
246#ifdef CONFIG_MEMORY_HOTPLUG
247static void free_page_ext(void *addr)
248{
249 if (is_vmalloc_addr(addr)) {
250 vfree(addr);
251 } else {
252 struct page *page = virt_to_page(addr);
253 size_t table_size;
254
255 table_size = sizeof(struct page_ext) * PAGES_PER_SECTION;
256
257 BUG_ON(PageReserved(page));
258 free_pages_exact(addr, table_size);
259 }
260}
261
262static void __free_page_ext(unsigned long pfn)
263{
264 struct mem_section *ms;
265 struct page_ext *base;
266
267 ms = __pfn_to_section(pfn);
268 if (!ms || !ms->page_ext)
269 return;
270 base = ms->page_ext + pfn;
271 free_page_ext(base);
272 ms->page_ext = NULL;
273}
274
275static int __meminit online_page_ext(unsigned long start_pfn,
276 unsigned long nr_pages,
277 int nid)
278{
279 unsigned long start, end, pfn;
280 int fail = 0;
281
282 start = SECTION_ALIGN_DOWN(start_pfn);
283 end = SECTION_ALIGN_UP(start_pfn + nr_pages);
284
285 if (nid == -1) {
286
287
288
289
290
291 nid = pfn_to_nid(start_pfn);
292 VM_BUG_ON(!node_state(nid, N_ONLINE));
293 }
294
295 for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) {
296 if (!pfn_present(pfn))
297 continue;
298 fail = init_section_page_ext(pfn, nid);
299 }
300 if (!fail)
301 return 0;
302
303
304 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
305 __free_page_ext(pfn);
306
307 return -ENOMEM;
308}
309
310static int __meminit offline_page_ext(unsigned long start_pfn,
311 unsigned long nr_pages, int nid)
312{
313 unsigned long start, end, pfn;
314
315 start = SECTION_ALIGN_DOWN(start_pfn);
316 end = SECTION_ALIGN_UP(start_pfn + nr_pages);
317
318 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION)
319 __free_page_ext(pfn);
320 return 0;
321
322}
323
324static int __meminit page_ext_callback(struct notifier_block *self,
325 unsigned long action, void *arg)
326{
327 struct memory_notify *mn = arg;
328 int ret = 0;
329
330 switch (action) {
331 case MEM_GOING_ONLINE:
332 ret = online_page_ext(mn->start_pfn,
333 mn->nr_pages, mn->status_change_nid);
334 break;
335 case MEM_OFFLINE:
336 offline_page_ext(mn->start_pfn,
337 mn->nr_pages, mn->status_change_nid);
338 break;
339 case MEM_CANCEL_ONLINE:
340 offline_page_ext(mn->start_pfn,
341 mn->nr_pages, mn->status_change_nid);
342 break;
343 case MEM_GOING_OFFLINE:
344 break;
345 case MEM_ONLINE:
346 case MEM_CANCEL_OFFLINE:
347 break;
348 }
349
350 return notifier_from_errno(ret);
351}
352
353#endif
354
355void __init page_ext_init(void)
356{
357 unsigned long pfn;
358 int nid;
359
360 if (!invoke_need_callbacks())
361 return;
362
363 for_each_node_state(nid, N_MEMORY) {
364 unsigned long start_pfn, end_pfn;
365
366 start_pfn = node_start_pfn(nid);
367 end_pfn = node_end_pfn(nid);
368
369
370
371
372
373 for (pfn = start_pfn; pfn < end_pfn;
374 pfn = ALIGN(pfn + 1, PAGES_PER_SECTION)) {
375
376 if (!pfn_valid(pfn))
377 continue;
378
379
380
381
382
383
384 if (pfn_to_nid(pfn) != nid)
385 continue;
386 if (init_section_page_ext(pfn, nid))
387 goto oom;
388 }
389 }
390 hotplug_memory_notifier(page_ext_callback, 0);
391 pr_info("allocated %ld bytes of page_ext\n", total_usage);
392 invoke_init_callbacks();
393 return;
394
395oom:
396 panic("Out of memory");
397}
398
399void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
400{
401}
402
403#endif
404