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Pull misc-2.6.39 into release branch
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / mm / init_64.c
1 /*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz>
6 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
7 */
8
9 #include <linux/signal.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/ptrace.h>
16 #include <linux/mman.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/smp.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/pagemap.h>
23 #include <linux/bootmem.h>
24 #include <linux/memblock.h>
25 #include <linux/proc_fs.h>
26 #include <linux/pci.h>
27 #include <linux/pfn.h>
28 #include <linux/poison.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/module.h>
31 #include <linux/memory_hotplug.h>
32 #include <linux/nmi.h>
33 #include <linux/gfp.h>
34
35 #include <asm/processor.h>
36 #include <asm/bios_ebda.h>
37 #include <asm/system.h>
38 #include <asm/uaccess.h>
39 #include <asm/pgtable.h>
40 #include <asm/pgalloc.h>
41 #include <asm/dma.h>
42 #include <asm/fixmap.h>
43 #include <asm/e820.h>
44 #include <asm/apic.h>
45 #include <asm/tlb.h>
46 #include <asm/mmu_context.h>
47 #include <asm/proto.h>
48 #include <asm/smp.h>
49 #include <asm/sections.h>
50 #include <asm/kdebug.h>
51 #include <asm/numa.h>
52 #include <asm/cacheflush.h>
53 #include <asm/init.h>
54
55 static int __init parse_direct_gbpages_off(char *arg)
56 {
57 direct_gbpages = 0;
58 return 0;
59 }
60 early_param("nogbpages", parse_direct_gbpages_off);
61
62 static int __init parse_direct_gbpages_on(char *arg)
63 {
64 direct_gbpages = 1;
65 return 0;
66 }
67 early_param("gbpages", parse_direct_gbpages_on);
68
69 /*
70 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
71 * physical space so we can cache the place of the first one and move
72 * around without checking the pgd every time.
73 */
74
75 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
76 EXPORT_SYMBOL_GPL(__supported_pte_mask);
77
78 int force_personality32;
79
80 /*
81 * noexec32=on|off
82 * Control non executable heap for 32bit processes.
83 * To control the stack too use noexec=off
84 *
85 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
86 * off PROT_READ implies PROT_EXEC
87 */
88 static int __init nonx32_setup(char *str)
89 {
90 if (!strcmp(str, "on"))
91 force_personality32 &= ~READ_IMPLIES_EXEC;
92 else if (!strcmp(str, "off"))
93 force_personality32 |= READ_IMPLIES_EXEC;
94 return 1;
95 }
96 __setup("noexec32=", nonx32_setup);
97
98 /*
99 * When memory was added/removed make sure all the processes MM have
100 * suitable PGD entries in the local PGD level page.
101 */
102 void sync_global_pgds(unsigned long start, unsigned long end)
103 {
104 unsigned long address;
105
106 for (address = start; address <= end; address += PGDIR_SIZE) {
107 const pgd_t *pgd_ref = pgd_offset_k(address);
108 struct page *page;
109
110 if (pgd_none(*pgd_ref))
111 continue;
112
113 spin_lock(&pgd_lock);
114 list_for_each_entry(page, &pgd_list, lru) {
115 pgd_t *pgd;
116 spinlock_t *pgt_lock;
117
118 pgd = (pgd_t *)page_address(page) + pgd_index(address);
119 /* the pgt_lock only for Xen */
120 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
121 spin_lock(pgt_lock);
122
123 if (pgd_none(*pgd))
124 set_pgd(pgd, *pgd_ref);
125 else
126 BUG_ON(pgd_page_vaddr(*pgd)
127 != pgd_page_vaddr(*pgd_ref));
128
129 spin_unlock(pgt_lock);
130 }
131 spin_unlock(&pgd_lock);
132 }
133 }
134
135 /*
136 * NOTE: This function is marked __ref because it calls __init function
137 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
138 */
139 static __ref void *spp_getpage(void)
140 {
141 void *ptr;
142
143 if (after_bootmem)
144 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
145 else
146 ptr = alloc_bootmem_pages(PAGE_SIZE);
147
148 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
149 panic("set_pte_phys: cannot allocate page data %s\n",
150 after_bootmem ? "after bootmem" : "");
151 }
152
153 pr_debug("spp_getpage %p\n", ptr);
154
155 return ptr;
156 }
157
158 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
159 {
160 if (pgd_none(*pgd)) {
161 pud_t *pud = (pud_t *)spp_getpage();
162 pgd_populate(&init_mm, pgd, pud);
163 if (pud != pud_offset(pgd, 0))
164 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
165 pud, pud_offset(pgd, 0));
166 }
167 return pud_offset(pgd, vaddr);
168 }
169
170 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
171 {
172 if (pud_none(*pud)) {
173 pmd_t *pmd = (pmd_t *) spp_getpage();
174 pud_populate(&init_mm, pud, pmd);
175 if (pmd != pmd_offset(pud, 0))
176 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
177 pmd, pmd_offset(pud, 0));
178 }
179 return pmd_offset(pud, vaddr);
180 }
181
182 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
183 {
184 if (pmd_none(*pmd)) {
185 pte_t *pte = (pte_t *) spp_getpage();
186 pmd_populate_kernel(&init_mm, pmd, pte);
187 if (pte != pte_offset_kernel(pmd, 0))
188 printk(KERN_ERR "PAGETABLE BUG #02!\n");
189 }
190 return pte_offset_kernel(pmd, vaddr);
191 }
192
193 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
194 {
195 pud_t *pud;
196 pmd_t *pmd;
197 pte_t *pte;
198
199 pud = pud_page + pud_index(vaddr);
200 pmd = fill_pmd(pud, vaddr);
201 pte = fill_pte(pmd, vaddr);
202
203 set_pte(pte, new_pte);
204
205 /*
206 * It's enough to flush this one mapping.
207 * (PGE mappings get flushed as well)
208 */
209 __flush_tlb_one(vaddr);
210 }
211
212 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
213 {
214 pgd_t *pgd;
215 pud_t *pud_page;
216
217 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
218
219 pgd = pgd_offset_k(vaddr);
220 if (pgd_none(*pgd)) {
221 printk(KERN_ERR
222 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
223 return;
224 }
225 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
226 set_pte_vaddr_pud(pud_page, vaddr, pteval);
227 }
228
229 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
230 {
231 pgd_t *pgd;
232 pud_t *pud;
233
234 pgd = pgd_offset_k(vaddr);
235 pud = fill_pud(pgd, vaddr);
236 return fill_pmd(pud, vaddr);
237 }
238
239 pte_t * __init populate_extra_pte(unsigned long vaddr)
240 {
241 pmd_t *pmd;
242
243 pmd = populate_extra_pmd(vaddr);
244 return fill_pte(pmd, vaddr);
245 }
246
247 /*
248 * Create large page table mappings for a range of physical addresses.
249 */
250 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
251 pgprot_t prot)
252 {
253 pgd_t *pgd;
254 pud_t *pud;
255 pmd_t *pmd;
256
257 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
258 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
259 pgd = pgd_offset_k((unsigned long)__va(phys));
260 if (pgd_none(*pgd)) {
261 pud = (pud_t *) spp_getpage();
262 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
263 _PAGE_USER));
264 }
265 pud = pud_offset(pgd, (unsigned long)__va(phys));
266 if (pud_none(*pud)) {
267 pmd = (pmd_t *) spp_getpage();
268 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
269 _PAGE_USER));
270 }
271 pmd = pmd_offset(pud, phys);
272 BUG_ON(!pmd_none(*pmd));
273 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
274 }
275 }
276
277 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
278 {
279 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
280 }
281
282 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
283 {
284 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
285 }
286
287 /*
288 * The head.S code sets up the kernel high mapping:
289 *
290 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
291 *
292 * phys_addr holds the negative offset to the kernel, which is added
293 * to the compile time generated pmds. This results in invalid pmds up
294 * to the point where we hit the physaddr 0 mapping.
295 *
296 * We limit the mappings to the region from _text to _end. _end is
297 * rounded up to the 2MB boundary. This catches the invalid pmds as
298 * well, as they are located before _text:
299 */
300 void __init cleanup_highmap(void)
301 {
302 unsigned long vaddr = __START_KERNEL_map;
303 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
304 pmd_t *pmd = level2_kernel_pgt;
305 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
306
307 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
308 if (pmd_none(*pmd))
309 continue;
310 if (vaddr < (unsigned long) _text || vaddr > end)
311 set_pmd(pmd, __pmd(0));
312 }
313 }
314
315 static __ref void *alloc_low_page(unsigned long *phys)
316 {
317 unsigned long pfn = e820_table_end++;
318 void *adr;
319
320 if (after_bootmem) {
321 adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
322 *phys = __pa(adr);
323
324 return adr;
325 }
326
327 if (pfn >= e820_table_top)
328 panic("alloc_low_page: ran out of memory");
329
330 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
331 clear_page(adr);
332 *phys = pfn * PAGE_SIZE;
333 return adr;
334 }
335
336 static __ref void unmap_low_page(void *adr)
337 {
338 if (after_bootmem)
339 return;
340
341 early_iounmap(adr, PAGE_SIZE);
342 }
343
344 static unsigned long __meminit
345 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
346 pgprot_t prot)
347 {
348 unsigned pages = 0;
349 unsigned long last_map_addr = end;
350 int i;
351
352 pte_t *pte = pte_page + pte_index(addr);
353
354 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
355
356 if (addr >= end) {
357 if (!after_bootmem) {
358 for(; i < PTRS_PER_PTE; i++, pte++)
359 set_pte(pte, __pte(0));
360 }
361 break;
362 }
363
364 /*
365 * We will re-use the existing mapping.
366 * Xen for example has some special requirements, like mapping
367 * pagetable pages as RO. So assume someone who pre-setup
368 * these mappings are more intelligent.
369 */
370 if (pte_val(*pte)) {
371 pages++;
372 continue;
373 }
374
375 if (0)
376 printk(" pte=%p addr=%lx pte=%016lx\n",
377 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
378 pages++;
379 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
380 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
381 }
382
383 update_page_count(PG_LEVEL_4K, pages);
384
385 return last_map_addr;
386 }
387
388 static unsigned long __meminit
389 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
390 pgprot_t prot)
391 {
392 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
393
394 return phys_pte_init(pte, address, end, prot);
395 }
396
397 static unsigned long __meminit
398 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
399 unsigned long page_size_mask, pgprot_t prot)
400 {
401 unsigned long pages = 0;
402 unsigned long last_map_addr = end;
403
404 int i = pmd_index(address);
405
406 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
407 unsigned long pte_phys;
408 pmd_t *pmd = pmd_page + pmd_index(address);
409 pte_t *pte;
410 pgprot_t new_prot = prot;
411
412 if (address >= end) {
413 if (!after_bootmem) {
414 for (; i < PTRS_PER_PMD; i++, pmd++)
415 set_pmd(pmd, __pmd(0));
416 }
417 break;
418 }
419
420 if (pmd_val(*pmd)) {
421 if (!pmd_large(*pmd)) {
422 spin_lock(&init_mm.page_table_lock);
423 last_map_addr = phys_pte_update(pmd, address,
424 end, prot);
425 spin_unlock(&init_mm.page_table_lock);
426 continue;
427 }
428 /*
429 * If we are ok with PG_LEVEL_2M mapping, then we will
430 * use the existing mapping,
431 *
432 * Otherwise, we will split the large page mapping but
433 * use the same existing protection bits except for
434 * large page, so that we don't violate Intel's TLB
435 * Application note (317080) which says, while changing
436 * the page sizes, new and old translations should
437 * not differ with respect to page frame and
438 * attributes.
439 */
440 if (page_size_mask & (1 << PG_LEVEL_2M)) {
441 pages++;
442 continue;
443 }
444 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
445 }
446
447 if (page_size_mask & (1<<PG_LEVEL_2M)) {
448 pages++;
449 spin_lock(&init_mm.page_table_lock);
450 set_pte((pte_t *)pmd,
451 pfn_pte(address >> PAGE_SHIFT,
452 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
453 spin_unlock(&init_mm.page_table_lock);
454 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
455 continue;
456 }
457
458 pte = alloc_low_page(&pte_phys);
459 last_map_addr = phys_pte_init(pte, address, end, new_prot);
460 unmap_low_page(pte);
461
462 spin_lock(&init_mm.page_table_lock);
463 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
464 spin_unlock(&init_mm.page_table_lock);
465 }
466 update_page_count(PG_LEVEL_2M, pages);
467 return last_map_addr;
468 }
469
470 static unsigned long __meminit
471 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
472 unsigned long page_size_mask, pgprot_t prot)
473 {
474 pmd_t *pmd = pmd_offset(pud, 0);
475 unsigned long last_map_addr;
476
477 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
478 __flush_tlb_all();
479 return last_map_addr;
480 }
481
482 static unsigned long __meminit
483 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
484 unsigned long page_size_mask)
485 {
486 unsigned long pages = 0;
487 unsigned long last_map_addr = end;
488 int i = pud_index(addr);
489
490 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
491 unsigned long pmd_phys;
492 pud_t *pud = pud_page + pud_index(addr);
493 pmd_t *pmd;
494 pgprot_t prot = PAGE_KERNEL;
495
496 if (addr >= end)
497 break;
498
499 if (!after_bootmem &&
500 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
501 set_pud(pud, __pud(0));
502 continue;
503 }
504
505 if (pud_val(*pud)) {
506 if (!pud_large(*pud)) {
507 last_map_addr = phys_pmd_update(pud, addr, end,
508 page_size_mask, prot);
509 continue;
510 }
511 /*
512 * If we are ok with PG_LEVEL_1G mapping, then we will
513 * use the existing mapping.
514 *
515 * Otherwise, we will split the gbpage mapping but use
516 * the same existing protection bits except for large
517 * page, so that we don't violate Intel's TLB
518 * Application note (317080) which says, while changing
519 * the page sizes, new and old translations should
520 * not differ with respect to page frame and
521 * attributes.
522 */
523 if (page_size_mask & (1 << PG_LEVEL_1G)) {
524 pages++;
525 continue;
526 }
527 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
528 }
529
530 if (page_size_mask & (1<<PG_LEVEL_1G)) {
531 pages++;
532 spin_lock(&init_mm.page_table_lock);
533 set_pte((pte_t *)pud,
534 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
535 spin_unlock(&init_mm.page_table_lock);
536 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
537 continue;
538 }
539
540 pmd = alloc_low_page(&pmd_phys);
541 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
542 prot);
543 unmap_low_page(pmd);
544
545 spin_lock(&init_mm.page_table_lock);
546 pud_populate(&init_mm, pud, __va(pmd_phys));
547 spin_unlock(&init_mm.page_table_lock);
548 }
549 __flush_tlb_all();
550
551 update_page_count(PG_LEVEL_1G, pages);
552
553 return last_map_addr;
554 }
555
556 static unsigned long __meminit
557 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
558 unsigned long page_size_mask)
559 {
560 pud_t *pud;
561
562 pud = (pud_t *)pgd_page_vaddr(*pgd);
563
564 return phys_pud_init(pud, addr, end, page_size_mask);
565 }
566
567 unsigned long __meminit
568 kernel_physical_mapping_init(unsigned long start,
569 unsigned long end,
570 unsigned long page_size_mask)
571 {
572 bool pgd_changed = false;
573 unsigned long next, last_map_addr = end;
574 unsigned long addr;
575
576 start = (unsigned long)__va(start);
577 end = (unsigned long)__va(end);
578 addr = start;
579
580 for (; start < end; start = next) {
581 pgd_t *pgd = pgd_offset_k(start);
582 unsigned long pud_phys;
583 pud_t *pud;
584
585 next = (start + PGDIR_SIZE) & PGDIR_MASK;
586 if (next > end)
587 next = end;
588
589 if (pgd_val(*pgd)) {
590 last_map_addr = phys_pud_update(pgd, __pa(start),
591 __pa(end), page_size_mask);
592 continue;
593 }
594
595 pud = alloc_low_page(&pud_phys);
596 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
597 page_size_mask);
598 unmap_low_page(pud);
599
600 spin_lock(&init_mm.page_table_lock);
601 pgd_populate(&init_mm, pgd, __va(pud_phys));
602 spin_unlock(&init_mm.page_table_lock);
603 pgd_changed = true;
604 }
605
606 if (pgd_changed)
607 sync_global_pgds(addr, end);
608
609 __flush_tlb_all();
610
611 return last_map_addr;
612 }
613
614 #ifndef CONFIG_NUMA
615 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn,
616 int acpi, int k8)
617 {
618 memblock_x86_register_active_regions(0, start_pfn, end_pfn);
619 }
620 #endif
621
622 void __init paging_init(void)
623 {
624 unsigned long max_zone_pfns[MAX_NR_ZONES];
625
626 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
627 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
628 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
629 max_zone_pfns[ZONE_NORMAL] = max_pfn;
630
631 sparse_memory_present_with_active_regions(MAX_NUMNODES);
632 sparse_init();
633
634 /*
635 * clear the default setting with node 0
636 * note: don't use nodes_clear here, that is really clearing when
637 * numa support is not compiled in, and later node_set_state
638 * will not set it back.
639 */
640 node_clear_state(0, N_NORMAL_MEMORY);
641
642 free_area_init_nodes(max_zone_pfns);
643 }
644
645 /*
646 * Memory hotplug specific functions
647 */
648 #ifdef CONFIG_MEMORY_HOTPLUG
649 /*
650 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
651 * updating.
652 */
653 static void update_end_of_memory_vars(u64 start, u64 size)
654 {
655 unsigned long end_pfn = PFN_UP(start + size);
656
657 if (end_pfn > max_pfn) {
658 max_pfn = end_pfn;
659 max_low_pfn = end_pfn;
660 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
661 }
662 }
663
664 /*
665 * Memory is added always to NORMAL zone. This means you will never get
666 * additional DMA/DMA32 memory.
667 */
668 int arch_add_memory(int nid, u64 start, u64 size)
669 {
670 struct pglist_data *pgdat = NODE_DATA(nid);
671 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
672 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
673 unsigned long nr_pages = size >> PAGE_SHIFT;
674 int ret;
675
676 last_mapped_pfn = init_memory_mapping(start, start + size);
677 if (last_mapped_pfn > max_pfn_mapped)
678 max_pfn_mapped = last_mapped_pfn;
679
680 ret = __add_pages(nid, zone, start_pfn, nr_pages);
681 WARN_ON_ONCE(ret);
682
683 /* update max_pfn, max_low_pfn and high_memory */
684 update_end_of_memory_vars(start, size);
685
686 return ret;
687 }
688 EXPORT_SYMBOL_GPL(arch_add_memory);
689
690 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
691 int memory_add_physaddr_to_nid(u64 start)
692 {
693 return 0;
694 }
695 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
696 #endif
697
698 #endif /* CONFIG_MEMORY_HOTPLUG */
699
700 static struct kcore_list kcore_vsyscall;
701
702 void __init mem_init(void)
703 {
704 long codesize, reservedpages, datasize, initsize;
705 unsigned long absent_pages;
706
707 pci_iommu_alloc();
708
709 /* clear_bss() already clear the empty_zero_page */
710
711 reservedpages = 0;
712
713 /* this will put all low memory onto the freelists */
714 #ifdef CONFIG_NUMA
715 totalram_pages = numa_free_all_bootmem();
716 #else
717 totalram_pages = free_all_bootmem();
718 #endif
719
720 absent_pages = absent_pages_in_range(0, max_pfn);
721 reservedpages = max_pfn - totalram_pages - absent_pages;
722 after_bootmem = 1;
723
724 codesize = (unsigned long) &_etext - (unsigned long) &_text;
725 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
726 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
727
728 /* Register memory areas for /proc/kcore */
729 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
730 VSYSCALL_END - VSYSCALL_START, KCORE_OTHER);
731
732 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
733 "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
734 nr_free_pages() << (PAGE_SHIFT-10),
735 max_pfn << (PAGE_SHIFT-10),
736 codesize >> 10,
737 absent_pages << (PAGE_SHIFT-10),
738 reservedpages << (PAGE_SHIFT-10),
739 datasize >> 10,
740 initsize >> 10);
741 }
742
743 #ifdef CONFIG_DEBUG_RODATA
744 const int rodata_test_data = 0xC3;
745 EXPORT_SYMBOL_GPL(rodata_test_data);
746
747 int kernel_set_to_readonly;
748
749 void set_kernel_text_rw(void)
750 {
751 unsigned long start = PFN_ALIGN(_text);
752 unsigned long end = PFN_ALIGN(__stop___ex_table);
753
754 if (!kernel_set_to_readonly)
755 return;
756
757 pr_debug("Set kernel text: %lx - %lx for read write\n",
758 start, end);
759
760 /*
761 * Make the kernel identity mapping for text RW. Kernel text
762 * mapping will always be RO. Refer to the comment in
763 * static_protections() in pageattr.c
764 */
765 set_memory_rw(start, (end - start) >> PAGE_SHIFT);
766 }
767
768 void set_kernel_text_ro(void)
769 {
770 unsigned long start = PFN_ALIGN(_text);
771 unsigned long end = PFN_ALIGN(__stop___ex_table);
772
773 if (!kernel_set_to_readonly)
774 return;
775
776 pr_debug("Set kernel text: %lx - %lx for read only\n",
777 start, end);
778
779 /*
780 * Set the kernel identity mapping for text RO.
781 */
782 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
783 }
784
785 void mark_rodata_ro(void)
786 {
787 unsigned long start = PFN_ALIGN(_text);
788 unsigned long rodata_start =
789 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
790 unsigned long end = (unsigned long) &__end_rodata_hpage_align;
791 unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table);
792 unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata);
793 unsigned long data_start = (unsigned long) &_sdata;
794
795 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
796 (end - start) >> 10);
797 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
798
799 kernel_set_to_readonly = 1;
800
801 /*
802 * The rodata section (but not the kernel text!) should also be
803 * not-executable.
804 */
805 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
806
807 rodata_test();
808
809 #ifdef CONFIG_CPA_DEBUG
810 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
811 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
812
813 printk(KERN_INFO "Testing CPA: again\n");
814 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
815 #endif
816
817 free_init_pages("unused kernel memory",
818 (unsigned long) page_address(virt_to_page(text_end)),
819 (unsigned long)
820 page_address(virt_to_page(rodata_start)));
821 free_init_pages("unused kernel memory",
822 (unsigned long) page_address(virt_to_page(rodata_end)),
823 (unsigned long) page_address(virt_to_page(data_start)));
824 }
825
826 #endif
827
828 int kern_addr_valid(unsigned long addr)
829 {
830 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
831 pgd_t *pgd;
832 pud_t *pud;
833 pmd_t *pmd;
834 pte_t *pte;
835
836 if (above != 0 && above != -1UL)
837 return 0;
838
839 pgd = pgd_offset_k(addr);
840 if (pgd_none(*pgd))
841 return 0;
842
843 pud = pud_offset(pgd, addr);
844 if (pud_none(*pud))
845 return 0;
846
847 pmd = pmd_offset(pud, addr);
848 if (pmd_none(*pmd))
849 return 0;
850
851 if (pmd_large(*pmd))
852 return pfn_valid(pmd_pfn(*pmd));
853
854 pte = pte_offset_kernel(pmd, addr);
855 if (pte_none(*pte))
856 return 0;
857
858 return pfn_valid(pte_pfn(*pte));
859 }
860
861 /*
862 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
863 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
864 * not need special handling anymore:
865 */
866 static struct vm_area_struct gate_vma = {
867 .vm_start = VSYSCALL_START,
868 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
869 .vm_page_prot = PAGE_READONLY_EXEC,
870 .vm_flags = VM_READ | VM_EXEC
871 };
872
873 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
874 {
875 #ifdef CONFIG_IA32_EMULATION
876 if (test_tsk_thread_flag(tsk, TIF_IA32))
877 return NULL;
878 #endif
879 return &gate_vma;
880 }
881
882 int in_gate_area(struct task_struct *task, unsigned long addr)
883 {
884 struct vm_area_struct *vma = get_gate_vma(task);
885
886 if (!vma)
887 return 0;
888
889 return (addr >= vma->vm_start) && (addr < vma->vm_end);
890 }
891
892 /*
893 * Use this when you have no reliable task/vma, typically from interrupt
894 * context. It is less reliable than using the task's vma and may give
895 * false positives:
896 */
897 int in_gate_area_no_task(unsigned long addr)
898 {
899 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
900 }
901
902 const char *arch_vma_name(struct vm_area_struct *vma)
903 {
904 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
905 return "[vdso]";
906 if (vma == &gate_vma)
907 return "[vsyscall]";
908 return NULL;
909 }
910
911 #ifdef CONFIG_SPARSEMEM_VMEMMAP
912 /*
913 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
914 */
915 static long __meminitdata addr_start, addr_end;
916 static void __meminitdata *p_start, *p_end;
917 static int __meminitdata node_start;
918
919 int __meminit
920 vmemmap_populate(struct page *start_page, unsigned long size, int node)
921 {
922 unsigned long addr = (unsigned long)start_page;
923 unsigned long end = (unsigned long)(start_page + size);
924 unsigned long next;
925 pgd_t *pgd;
926 pud_t *pud;
927 pmd_t *pmd;
928
929 for (; addr < end; addr = next) {
930 void *p = NULL;
931
932 pgd = vmemmap_pgd_populate(addr, node);
933 if (!pgd)
934 return -ENOMEM;
935
936 pud = vmemmap_pud_populate(pgd, addr, node);
937 if (!pud)
938 return -ENOMEM;
939
940 if (!cpu_has_pse) {
941 next = (addr + PAGE_SIZE) & PAGE_MASK;
942 pmd = vmemmap_pmd_populate(pud, addr, node);
943
944 if (!pmd)
945 return -ENOMEM;
946
947 p = vmemmap_pte_populate(pmd, addr, node);
948
949 if (!p)
950 return -ENOMEM;
951
952 addr_end = addr + PAGE_SIZE;
953 p_end = p + PAGE_SIZE;
954 } else {
955 next = pmd_addr_end(addr, end);
956
957 pmd = pmd_offset(pud, addr);
958 if (pmd_none(*pmd)) {
959 pte_t entry;
960
961 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
962 if (!p)
963 return -ENOMEM;
964
965 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
966 PAGE_KERNEL_LARGE);
967 set_pmd(pmd, __pmd(pte_val(entry)));
968
969 /* check to see if we have contiguous blocks */
970 if (p_end != p || node_start != node) {
971 if (p_start)
972 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
973 addr_start, addr_end-1, p_start, p_end-1, node_start);
974 addr_start = addr;
975 node_start = node;
976 p_start = p;
977 }
978
979 addr_end = addr + PMD_SIZE;
980 p_end = p + PMD_SIZE;
981 } else
982 vmemmap_verify((pte_t *)pmd, node, addr, next);
983 }
984
985 }
986 sync_global_pgds((unsigned long)start_page, end);
987 return 0;
988 }
989
990 void __meminit vmemmap_populate_print_last(void)
991 {
992 if (p_start) {
993 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
994 addr_start, addr_end-1, p_start, p_end-1, node_start);
995 p_start = NULL;
996 p_end = NULL;
997 node_start = 0;
998 }
999 }
1000 #endif
kernel source for telekom puls (alcatel/mediatek)