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