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x86: un-__init fill_pud/pmd/pte
[linux-2.6/linux-2.6-openrd.git] / arch / x86 / mm / init_64.c
blob07f44d491df16d9b392fdaa09e3bdf4143f3c236
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/proc_fs.h>
25 #include <linux/pci.h>
26 #include <linux/pfn.h>
27 #include <linux/poison.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/module.h>
30 #include <linux/memory_hotplug.h>
31 #include <linux/nmi.h>
32
33 #include <asm/processor.h>
34 #include <asm/bios_ebda.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
37 #include <asm/pgtable.h>
38 #include <asm/pgalloc.h>
39 #include <asm/dma.h>
40 #include <asm/fixmap.h>
41 #include <asm/e820.h>
42 #include <asm/apic.h>
43 #include <asm/tlb.h>
44 #include <asm/mmu_context.h>
45 #include <asm/proto.h>
46 #include <asm/smp.h>
47 #include <asm/sections.h>
48 #include <asm/kdebug.h>
49 #include <asm/numa.h>
50 #include <asm/cacheflush.h>
51
52 /*
53 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
54 * The direct mapping extends to max_pfn_mapped, so that we can directly access
55 * apertures, ACPI and other tables without having to play with fixmaps.
56 */
57 unsigned long max_low_pfn_mapped;
58 unsigned long max_pfn_mapped;
59
60 static unsigned long dma_reserve __initdata;
61
62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
63
64 int direct_gbpages
65 #ifdef CONFIG_DIRECT_GBPAGES
66 = 1
67 #endif
68 ;
69
70 static int __init parse_direct_gbpages_off(char *arg)
71 {
72 direct_gbpages = 0;
73 return 0;
74 }
75 early_param("nogbpages", parse_direct_gbpages_off);
76
77 static int __init parse_direct_gbpages_on(char *arg)
78 {
79 direct_gbpages = 1;
80 return 0;
81 }
82 early_param("gbpages", parse_direct_gbpages_on);
83
84 /*
85 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
86 * physical space so we can cache the place of the first one and move
87 * around without checking the pgd every time.
88 */
89
90 int after_bootmem;
91
92 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
93 EXPORT_SYMBOL_GPL(__supported_pte_mask);
94
95 static int do_not_nx __cpuinitdata;
96
97 /*
98 * noexec=on|off
99 * Control non-executable mappings for 64-bit processes.
100 *
101 * on Enable (default)
102 * off Disable
103 */
104 static int __init nonx_setup(char *str)
105 {
106 if (!str)
107 return -EINVAL;
108 if (!strncmp(str, "on", 2)) {
109 __supported_pte_mask |= _PAGE_NX;
110 do_not_nx = 0;
111 } else if (!strncmp(str, "off", 3)) {
112 do_not_nx = 1;
113 __supported_pte_mask &= ~_PAGE_NX;
114 }
115 return 0;
116 }
117 early_param("noexec", nonx_setup);
118
119 void __cpuinit check_efer(void)
120 {
121 unsigned long efer;
122
123 rdmsrl(MSR_EFER, efer);
124 if (!(efer & EFER_NX) || do_not_nx)
125 __supported_pte_mask &= ~_PAGE_NX;
126 }
127
128 int force_personality32;
129
130 /*
131 * noexec32=on|off
132 * Control non executable heap for 32bit processes.
133 * To control the stack too use noexec=off
134 *
135 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
136 * off PROT_READ implies PROT_EXEC
137 */
138 static int __init nonx32_setup(char *str)
139 {
140 if (!strcmp(str, "on"))
141 force_personality32 &= ~READ_IMPLIES_EXEC;
142 else if (!strcmp(str, "off"))
143 force_personality32 |= READ_IMPLIES_EXEC;
144 return 1;
145 }
146 __setup("noexec32=", nonx32_setup);
147
148 /*
149 * NOTE: This function is marked __ref because it calls __init function
150 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
151 */
152 static __ref void *spp_getpage(void)
153 {
154 void *ptr;
155
156 if (after_bootmem)
157 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
158 else
159 ptr = alloc_bootmem_pages(PAGE_SIZE);
160
161 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
162 panic("set_pte_phys: cannot allocate page data %s\n",
163 after_bootmem ? "after bootmem" : "");
164 }
165
166 pr_debug("spp_getpage %p\n", ptr);
167
168 return ptr;
169 }
170
171 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
172 {
173 if (pgd_none(*pgd)) {
174 pud_t *pud = (pud_t *)spp_getpage();
175 pgd_populate(&init_mm, pgd, pud);
176 if (pud != pud_offset(pgd, 0))
177 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
178 pud, pud_offset(pgd, 0));
179 }
180 return pud_offset(pgd, vaddr);
181 }
182
183 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
184 {
185 if (pud_none(*pud)) {
186 pmd_t *pmd = (pmd_t *) spp_getpage();
187 pud_populate(&init_mm, pud, pmd);
188 if (pmd != pmd_offset(pud, 0))
189 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
190 pmd, pmd_offset(pud, 0));
191 }
192 return pmd_offset(pud, vaddr);
193 }
194
195 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
196 {
197 if (pmd_none(*pmd)) {
198 pte_t *pte = (pte_t *) spp_getpage();
199 pmd_populate_kernel(&init_mm, pmd, pte);
200 if (pte != pte_offset_kernel(pmd, 0))
201 printk(KERN_ERR "PAGETABLE BUG #02!\n");
202 }
203 return pte_offset_kernel(pmd, vaddr);
204 }
205
206 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
207 {
208 pud_t *pud;
209 pmd_t *pmd;
210 pte_t *pte;
211
212 pud = pud_page + pud_index(vaddr);
213 pmd = fill_pmd(pud, vaddr);
214 pte = fill_pte(pmd, vaddr);
215
216 set_pte(pte, new_pte);
217
218 /*
219 * It's enough to flush this one mapping.
220 * (PGE mappings get flushed as well)
221 */
222 __flush_tlb_one(vaddr);
223 }
224
225 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
226 {
227 pgd_t *pgd;
228 pud_t *pud_page;
229
230 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
231
232 pgd = pgd_offset_k(vaddr);
233 if (pgd_none(*pgd)) {
234 printk(KERN_ERR
235 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
236 return;
237 }
238 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
239 set_pte_vaddr_pud(pud_page, vaddr, pteval);
240 }
241
242 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
243 {
244 pgd_t *pgd;
245 pud_t *pud;
246
247 pgd = pgd_offset_k(vaddr);
248 pud = fill_pud(pgd, vaddr);
249 return fill_pmd(pud, vaddr);
250 }
251
252 pte_t * __init populate_extra_pte(unsigned long vaddr)
253 {
254 pmd_t *pmd;
255
256 pmd = populate_extra_pmd(vaddr);
257 return fill_pte(pmd, vaddr);
258 }
259
260 /*
261 * Create large page table mappings for a range of physical addresses.
262 */
263 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
264 pgprot_t prot)
265 {
266 pgd_t *pgd;
267 pud_t *pud;
268 pmd_t *pmd;
269
270 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
271 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
272 pgd = pgd_offset_k((unsigned long)__va(phys));
273 if (pgd_none(*pgd)) {
274 pud = (pud_t *) spp_getpage();
275 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
276 _PAGE_USER));
277 }
278 pud = pud_offset(pgd, (unsigned long)__va(phys));
279 if (pud_none(*pud)) {
280 pmd = (pmd_t *) spp_getpage();
281 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
282 _PAGE_USER));
283 }
284 pmd = pmd_offset(pud, phys);
285 BUG_ON(!pmd_none(*pmd));
286 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
287 }
288 }
289
290 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
291 {
292 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
293 }
294
295 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
296 {
297 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
298 }
299
300 /*
301 * The head.S code sets up the kernel high mapping:
302 *
303 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
304 *
305 * phys_addr holds the negative offset to the kernel, which is added
306 * to the compile time generated pmds. This results in invalid pmds up
307 * to the point where we hit the physaddr 0 mapping.
308 *
309 * We limit the mappings to the region from _text to _end. _end is
310 * rounded up to the 2MB boundary. This catches the invalid pmds as
311 * well, as they are located before _text:
312 */
313 void __init cleanup_highmap(void)
314 {
315 unsigned long vaddr = __START_KERNEL_map;
316 unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
317 pmd_t *pmd = level2_kernel_pgt;
318 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
319
320 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
321 if (pmd_none(*pmd))
322 continue;
323 if (vaddr < (unsigned long) _text || vaddr > end)
324 set_pmd(pmd, __pmd(0));
325 }
326 }
327
328 static unsigned long __initdata table_start;
329 static unsigned long __meminitdata table_end;
330 static unsigned long __meminitdata table_top;
331
332 static __ref void *alloc_low_page(unsigned long *phys)
333 {
334 unsigned long pfn = table_end++;
335 void *adr;
336
337 if (after_bootmem) {
338 adr = (void *)get_zeroed_page(GFP_ATOMIC);
339 *phys = __pa(adr);
340
341 return adr;
342 }
343
344 if (pfn >= table_top)
345 panic("alloc_low_page: ran out of memory");
346
347 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
348 memset(adr, 0, PAGE_SIZE);
349 *phys = pfn * PAGE_SIZE;
350 return adr;
351 }
352
353 static __ref void unmap_low_page(void *adr)
354 {
355 if (after_bootmem)
356 return;
357
358 early_iounmap(adr, PAGE_SIZE);
359 }
360
361 static unsigned long __meminit
362 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
363 pgprot_t prot)
364 {
365 unsigned pages = 0;
366 unsigned long last_map_addr = end;
367 int i;
368
369 pte_t *pte = pte_page + pte_index(addr);
370
371 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
372
373 if (addr >= end) {
374 if (!after_bootmem) {
375 for(; i < PTRS_PER_PTE; i++, pte++)
376 set_pte(pte, __pte(0));
377 }
378 break;
379 }
380
381 /*
382 * We will re-use the existing mapping.
383 * Xen for example has some special requirements, like mapping
384 * pagetable pages as RO. So assume someone who pre-setup
385 * these mappings are more intelligent.
386 */
387 if (pte_val(*pte)) {
388 pages++;
389 continue;
390 }
391
392 if (0)
393 printk(" pte=%p addr=%lx pte=%016lx\n",
394 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
395 pages++;
396 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
397 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
398 }
399
400 update_page_count(PG_LEVEL_4K, pages);
401
402 return last_map_addr;
403 }
404
405 static unsigned long __meminit
406 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
407 pgprot_t prot)
408 {
409 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
410
411 return phys_pte_init(pte, address, end, prot);
412 }
413
414 static unsigned long __meminit
415 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
416 unsigned long page_size_mask, pgprot_t prot)
417 {
418 unsigned long pages = 0;
419 unsigned long last_map_addr = end;
420
421 int i = pmd_index(address);
422
423 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
424 unsigned long pte_phys;
425 pmd_t *pmd = pmd_page + pmd_index(address);
426 pte_t *pte;
427 pgprot_t new_prot = prot;
428
429 if (address >= end) {
430 if (!after_bootmem) {
431 for (; i < PTRS_PER_PMD; i++, pmd++)
432 set_pmd(pmd, __pmd(0));
433 }
434 break;
435 }
436
437 if (pmd_val(*pmd)) {
438 if (!pmd_large(*pmd)) {
439 spin_lock(&init_mm.page_table_lock);
440 last_map_addr = phys_pte_update(pmd, address,
441 end, prot);
442 spin_unlock(&init_mm.page_table_lock);
443 continue;
444 }
445 /*
446 * If we are ok with PG_LEVEL_2M mapping, then we will
447 * use the existing mapping,
448 *
449 * Otherwise, we will split the large page mapping but
450 * use the same existing protection bits except for
451 * large page, so that we don't violate Intel's TLB
452 * Application note (317080) which says, while changing
453 * the page sizes, new and old translations should
454 * not differ with respect to page frame and
455 * attributes.
456 */
457 if (page_size_mask & (1 << PG_LEVEL_2M)) {
458 pages++;
459 continue;
460 }
461 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
462 }
463
464 if (page_size_mask & (1<<PG_LEVEL_2M)) {
465 pages++;
466 spin_lock(&init_mm.page_table_lock);
467 set_pte((pte_t *)pmd,
468 pfn_pte(address >> PAGE_SHIFT,
469 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
470 spin_unlock(&init_mm.page_table_lock);
471 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
472 continue;
473 }
474
475 pte = alloc_low_page(&pte_phys);
476 last_map_addr = phys_pte_init(pte, address, end, new_prot);
477 unmap_low_page(pte);
478
479 spin_lock(&init_mm.page_table_lock);
480 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
481 spin_unlock(&init_mm.page_table_lock);
482 }
483 update_page_count(PG_LEVEL_2M, pages);
484 return last_map_addr;
485 }
486
487 static unsigned long __meminit
488 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
489 unsigned long page_size_mask, pgprot_t prot)
490 {
491 pmd_t *pmd = pmd_offset(pud, 0);
492 unsigned long last_map_addr;
493
494 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
495 __flush_tlb_all();
496 return last_map_addr;
497 }
498
499 static unsigned long __meminit
500 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
501 unsigned long page_size_mask)
502 {
503 unsigned long pages = 0;
504 unsigned long last_map_addr = end;
505 int i = pud_index(addr);
506
507 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
508 unsigned long pmd_phys;
509 pud_t *pud = pud_page + pud_index(addr);
510 pmd_t *pmd;
511 pgprot_t prot = PAGE_KERNEL;
512
513 if (addr >= end)
514 break;
515
516 if (!after_bootmem &&
517 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
518 set_pud(pud, __pud(0));
519 continue;
520 }
521
522 if (pud_val(*pud)) {
523 if (!pud_large(*pud)) {
524 last_map_addr = phys_pmd_update(pud, addr, end,
525 page_size_mask, prot);
526 continue;
527 }
528 /*
529 * If we are ok with PG_LEVEL_1G mapping, then we will
530 * use the existing mapping.
531 *
532 * Otherwise, we will split the gbpage mapping but use
533 * the same existing protection bits except for large
534 * page, so that we don't violate Intel's TLB
535 * Application note (317080) which says, while changing
536 * the page sizes, new and old translations should
537 * not differ with respect to page frame and
538 * attributes.
539 */
540 if (page_size_mask & (1 << PG_LEVEL_1G)) {
541 pages++;
542 continue;
543 }
544 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
545 }
546
547 if (page_size_mask & (1<<PG_LEVEL_1G)) {
548 pages++;
549 spin_lock(&init_mm.page_table_lock);
550 set_pte((pte_t *)pud,
551 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
552 spin_unlock(&init_mm.page_table_lock);
553 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
554 continue;
555 }
556
557 pmd = alloc_low_page(&pmd_phys);
558 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
559 prot);
560 unmap_low_page(pmd);
561
562 spin_lock(&init_mm.page_table_lock);
563 pud_populate(&init_mm, pud, __va(pmd_phys));
564 spin_unlock(&init_mm.page_table_lock);
565 }
566 __flush_tlb_all();
567
568 update_page_count(PG_LEVEL_1G, pages);
569
570 return last_map_addr;
571 }
572
573 static unsigned long __meminit
574 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
575 unsigned long page_size_mask)
576 {
577 pud_t *pud;
578
579 pud = (pud_t *)pgd_page_vaddr(*pgd);
580
581 return phys_pud_init(pud, addr, end, page_size_mask);
582 }
583
584 static void __init find_early_table_space(unsigned long end, int use_pse,
585 int use_gbpages)
586 {
587 unsigned long puds, pmds, ptes, tables, start;
588
589 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
590 tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
591 if (use_gbpages) {
592 unsigned long extra;
593 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
594 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
595 } else
596 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
597 tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
598
599 if (use_pse) {
600 unsigned long extra;
601 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
602 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
603 } else
604 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
605 tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
606
607 /*
608 * RED-PEN putting page tables only on node 0 could
609 * cause a hotspot and fill up ZONE_DMA. The page tables
610 * need roughly 0.5KB per GB.
611 */
612 start = 0x8000;
613 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
614 if (table_start == -1UL)
615 panic("Cannot find space for the kernel page tables");
616
617 table_start >>= PAGE_SHIFT;
618 table_end = table_start;
619 table_top = table_start + (tables >> PAGE_SHIFT);
620
621 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
622 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
623 }
624
625 static void __init init_gbpages(void)
626 {
627 if (direct_gbpages && cpu_has_gbpages)
628 printk(KERN_INFO "Using GB pages for direct mapping\n");
629 else
630 direct_gbpages = 0;
631 }
632
633 static unsigned long __meminit kernel_physical_mapping_init(unsigned long start,
634 unsigned long end,
635 unsigned long page_size_mask)
636 {
637
638 unsigned long next, last_map_addr = end;
639
640 start = (unsigned long)__va(start);
641 end = (unsigned long)__va(end);
642
643 for (; start < end; start = next) {
644 pgd_t *pgd = pgd_offset_k(start);
645 unsigned long pud_phys;
646 pud_t *pud;
647
648 next = (start + PGDIR_SIZE) & PGDIR_MASK;
649 if (next > end)
650 next = end;
651
652 if (pgd_val(*pgd)) {
653 last_map_addr = phys_pud_update(pgd, __pa(start),
654 __pa(end), page_size_mask);
655 continue;
656 }
657
658 pud = alloc_low_page(&pud_phys);
659 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
660 page_size_mask);
661 unmap_low_page(pud);
662
663 spin_lock(&init_mm.page_table_lock);
664 pgd_populate(&init_mm, pgd, __va(pud_phys));
665 spin_unlock(&init_mm.page_table_lock);
666 }
667 __flush_tlb_all();
668
669 return last_map_addr;
670 }
671
672 struct map_range {
673 unsigned long start;
674 unsigned long end;
675 unsigned page_size_mask;
676 };
677
678 #define NR_RANGE_MR 5
679
680 static int save_mr(struct map_range *mr, int nr_range,
681 unsigned long start_pfn, unsigned long end_pfn,
682 unsigned long page_size_mask)
683 {
684
685 if (start_pfn < end_pfn) {
686 if (nr_range >= NR_RANGE_MR)
687 panic("run out of range for init_memory_mapping\n");
688 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
689 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
690 mr[nr_range].page_size_mask = page_size_mask;
691 nr_range++;
692 }
693
694 return nr_range;
695 }
696
697 /*
698 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
699 * This runs before bootmem is initialized and gets pages directly from
700 * the physical memory. To access them they are temporarily mapped.
701 */
702 unsigned long __init_refok init_memory_mapping(unsigned long start,
703 unsigned long end)
704 {
705 unsigned long last_map_addr = 0;
706 unsigned long page_size_mask = 0;
707 unsigned long start_pfn, end_pfn;
708 unsigned long pos;
709
710 struct map_range mr[NR_RANGE_MR];
711 int nr_range, i;
712 int use_pse, use_gbpages;
713
714 printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
715
716 /*
717 * Find space for the kernel direct mapping tables.
718 *
719 * Later we should allocate these tables in the local node of the
720 * memory mapped. Unfortunately this is done currently before the
721 * nodes are discovered.
722 */
723 if (!after_bootmem)
724 init_gbpages();
725
726 #ifdef CONFIG_DEBUG_PAGEALLOC
727 /*
728 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
729 * This will simplify cpa(), which otherwise needs to support splitting
730 * large pages into small in interrupt context, etc.
731 */
732 use_pse = use_gbpages = 0;
733 #else
734 use_pse = cpu_has_pse;
735 use_gbpages = direct_gbpages;
736 #endif
737
738 if (use_gbpages)
739 page_size_mask |= 1 << PG_LEVEL_1G;
740 if (use_pse)
741 page_size_mask |= 1 << PG_LEVEL_2M;
742
743 memset(mr, 0, sizeof(mr));
744 nr_range = 0;
745
746 /* head if not big page alignment ?*/
747 start_pfn = start >> PAGE_SHIFT;
748 pos = start_pfn << PAGE_SHIFT;
749 end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
750 << (PMD_SHIFT - PAGE_SHIFT);
751 if (end_pfn > (end >> PAGE_SHIFT))
752 end_pfn = end >> PAGE_SHIFT;
753 if (start_pfn < end_pfn) {
754 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
755 pos = end_pfn << PAGE_SHIFT;
756 }
757
758 /* big page (2M) range*/
759 start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
760 << (PMD_SHIFT - PAGE_SHIFT);
761 end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
762 << (PUD_SHIFT - PAGE_SHIFT);
763 if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
764 end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
765 if (start_pfn < end_pfn) {
766 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
767 page_size_mask & (1<<PG_LEVEL_2M));
768 pos = end_pfn << PAGE_SHIFT;
769 }
770
771 /* big page (1G) range */
772 start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
773 << (PUD_SHIFT - PAGE_SHIFT);
774 end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
775 if (start_pfn < end_pfn) {
776 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
777 page_size_mask &
778 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
779 pos = end_pfn << PAGE_SHIFT;
780 }
781
782 /* tail is not big page (1G) alignment */
783 start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
784 << (PMD_SHIFT - PAGE_SHIFT);
785 end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
786 if (start_pfn < end_pfn) {
787 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
788 page_size_mask & (1<<PG_LEVEL_2M));
789 pos = end_pfn << PAGE_SHIFT;
790 }
791
792 /* tail is not big page (2M) alignment */
793 start_pfn = pos>>PAGE_SHIFT;
794 end_pfn = end>>PAGE_SHIFT;
795 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
796
797 /* try to merge same page size and continuous */
798 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
799 unsigned long old_start;
800 if (mr[i].end != mr[i+1].start ||
801 mr[i].page_size_mask != mr[i+1].page_size_mask)
802 continue;
803 /* move it */
804 old_start = mr[i].start;
805 memmove(&mr[i], &mr[i+1],
806 (nr_range - 1 - i) * sizeof (struct map_range));
807 mr[i--].start = old_start;
808 nr_range--;
809 }
810
811 for (i = 0; i < nr_range; i++)
812 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
813 mr[i].start, mr[i].end,
814 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
815 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
816
817 if (!after_bootmem)
818 find_early_table_space(end, use_pse, use_gbpages);
819
820 for (i = 0; i < nr_range; i++)
821 last_map_addr = kernel_physical_mapping_init(
822 mr[i].start, mr[i].end,
823 mr[i].page_size_mask);
824
825 if (!after_bootmem)
826 mmu_cr4_features = read_cr4();
827 __flush_tlb_all();
828
829 if (!after_bootmem && table_end > table_start)
830 reserve_early(table_start << PAGE_SHIFT,
831 table_end << PAGE_SHIFT, "PGTABLE");
832
833 printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
834 last_map_addr, end);
835
836 if (!after_bootmem)
837 early_memtest(start, end);
838
839 return last_map_addr >> PAGE_SHIFT;
840 }
841
842 #ifndef CONFIG_NUMA
843 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
844 {
845 unsigned long bootmap_size, bootmap;
846
847 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
848 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
849 PAGE_SIZE);
850 if (bootmap == -1L)
851 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
852 /* don't touch min_low_pfn */
853 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
854 0, end_pfn);
855 e820_register_active_regions(0, start_pfn, end_pfn);
856 free_bootmem_with_active_regions(0, end_pfn);
857 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
858 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
859 }
860
861 void __init paging_init(void)
862 {
863 unsigned long max_zone_pfns[MAX_NR_ZONES];
864
865 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
866 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
867 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
868 max_zone_pfns[ZONE_NORMAL] = max_pfn;
869
870 memory_present(0, 0, max_pfn);
871 sparse_init();
872 free_area_init_nodes(max_zone_pfns);
873 }
874 #endif
875
876 /*
877 * Memory hotplug specific functions
878 */
879 #ifdef CONFIG_MEMORY_HOTPLUG
880 /*
881 * Memory is added always to NORMAL zone. This means you will never get
882 * additional DMA/DMA32 memory.
883 */
884 int arch_add_memory(int nid, u64 start, u64 size)
885 {
886 struct pglist_data *pgdat = NODE_DATA(nid);
887 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
888 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
889 unsigned long nr_pages = size >> PAGE_SHIFT;
890 int ret;
891
892 last_mapped_pfn = init_memory_mapping(start, start + size);
893 if (last_mapped_pfn > max_pfn_mapped)
894 max_pfn_mapped = last_mapped_pfn;
895
896 ret = __add_pages(nid, zone, start_pfn, nr_pages);
897 WARN_ON_ONCE(ret);
898
899 return ret;
900 }
901 EXPORT_SYMBOL_GPL(arch_add_memory);
902
903 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
904 int memory_add_physaddr_to_nid(u64 start)
905 {
906 return 0;
907 }
908 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
909 #endif
910
911 #endif /* CONFIG_MEMORY_HOTPLUG */
912
913 /*
914 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
915 * is valid. The argument is a physical page number.
916 *
917 *
918 * On x86, access has to be given to the first megabyte of ram because that area
919 * contains bios code and data regions used by X and dosemu and similar apps.
920 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
921 * mmio resources as well as potential bios/acpi data regions.
922 */
923 int devmem_is_allowed(unsigned long pagenr)
924 {
925 if (pagenr <= 256)
926 return 1;
927 if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
928 return 0;
929 if (!page_is_ram(pagenr))
930 return 1;
931 return 0;
932 }
933
934
935 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
936 kcore_modules, kcore_vsyscall;
937
938 void __init mem_init(void)
939 {
940 long codesize, reservedpages, datasize, initsize;
941 unsigned long absent_pages;
942
943 pci_iommu_alloc();
944
945 /* clear_bss() already clear the empty_zero_page */
946
947 reservedpages = 0;
948
949 /* this will put all low memory onto the freelists */
950 #ifdef CONFIG_NUMA
951 totalram_pages = numa_free_all_bootmem();
952 #else
953 totalram_pages = free_all_bootmem();
954 #endif
955
956 absent_pages = absent_pages_in_range(0, max_pfn);
957 reservedpages = max_pfn - totalram_pages - absent_pages;
958 after_bootmem = 1;
959
960 codesize = (unsigned long) &_etext - (unsigned long) &_text;
961 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
962 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
963
964 /* Register memory areas for /proc/kcore */
965 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
966 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
967 VMALLOC_END-VMALLOC_START);
968 kclist_add(&kcore_kernel, &_stext, _end - _stext);
969 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
970 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
971 VSYSCALL_END - VSYSCALL_START);
972
973 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
974 "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
975 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
976 max_pfn << (PAGE_SHIFT-10),
977 codesize >> 10,
978 absent_pages << (PAGE_SHIFT-10),
979 reservedpages << (PAGE_SHIFT-10),
980 datasize >> 10,
981 initsize >> 10);
982 }
983
984 #ifdef CONFIG_DEBUG_RODATA
985 const int rodata_test_data = 0xC3;
986 EXPORT_SYMBOL_GPL(rodata_test_data);
987
988 void mark_rodata_ro(void)
989 {
990 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
991 unsigned long rodata_start =
992 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
993
994 #ifdef CONFIG_DYNAMIC_FTRACE
995 /* Dynamic tracing modifies the kernel text section */
996 start = rodata_start;
997 #endif
998
999 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1000 (end - start) >> 10);
1001 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1002
1003 /*
1004 * The rodata section (but not the kernel text!) should also be
1005 * not-executable.
1006 */
1007 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
1008
1009 rodata_test();
1010
1011 #ifdef CONFIG_CPA_DEBUG
1012 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1013 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1014
1015 printk(KERN_INFO "Testing CPA: again\n");
1016 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1017 #endif
1018 }
1019
1020 #endif
1021
1022 #ifdef CONFIG_BLK_DEV_INITRD
1023 void free_initrd_mem(unsigned long start, unsigned long end)
1024 {
1025 free_init_pages("initrd memory", start, end);
1026 }
1027 #endif
1028
1029 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
1030 int flags)
1031 {
1032 #ifdef CONFIG_NUMA
1033 int nid, next_nid;
1034 int ret;
1035 #endif
1036 unsigned long pfn = phys >> PAGE_SHIFT;
1037
1038 if (pfn >= max_pfn) {
1039 /*
1040 * This can happen with kdump kernels when accessing
1041 * firmware tables:
1042 */
1043 if (pfn < max_pfn_mapped)
1044 return -EFAULT;
1045
1046 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
1047 phys, len);
1048 return -EFAULT;
1049 }
1050
1051 /* Should check here against the e820 map to avoid double free */
1052 #ifdef CONFIG_NUMA
1053 nid = phys_to_nid(phys);
1054 next_nid = phys_to_nid(phys + len - 1);
1055 if (nid == next_nid)
1056 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
1057 else
1058 ret = reserve_bootmem(phys, len, flags);
1059
1060 if (ret != 0)
1061 return ret;
1062
1063 #else
1064 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
1065 #endif
1066
1067 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
1068 dma_reserve += len / PAGE_SIZE;
1069 set_dma_reserve(dma_reserve);
1070 }
1071
1072 return 0;
1073 }
1074
1075 int kern_addr_valid(unsigned long addr)
1076 {
1077 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1078 pgd_t *pgd;
1079 pud_t *pud;
1080 pmd_t *pmd;
1081 pte_t *pte;
1082
1083 if (above != 0 && above != -1UL)
1084 return 0;
1085
1086 pgd = pgd_offset_k(addr);
1087 if (pgd_none(*pgd))
1088 return 0;
1089
1090 pud = pud_offset(pgd, addr);
1091 if (pud_none(*pud))
1092 return 0;
1093
1094 pmd = pmd_offset(pud, addr);
1095 if (pmd_none(*pmd))
1096 return 0;
1097
1098 if (pmd_large(*pmd))
1099 return pfn_valid(pmd_pfn(*pmd));
1100
1101 pte = pte_offset_kernel(pmd, addr);
1102 if (pte_none(*pte))
1103 return 0;
1104
1105 return pfn_valid(pte_pfn(*pte));
1106 }
1107
1108 /*
1109 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
1110 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1111 * not need special handling anymore:
1112 */
1113 static struct vm_area_struct gate_vma = {
1114 .vm_start = VSYSCALL_START,
1115 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1116 .vm_page_prot = PAGE_READONLY_EXEC,
1117 .vm_flags = VM_READ | VM_EXEC
1118 };
1119
1120 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
1121 {
1122 #ifdef CONFIG_IA32_EMULATION
1123 if (test_tsk_thread_flag(tsk, TIF_IA32))
1124 return NULL;
1125 #endif
1126 return &gate_vma;
1127 }
1128
1129 int in_gate_area(struct task_struct *task, unsigned long addr)
1130 {
1131 struct vm_area_struct *vma = get_gate_vma(task);
1132
1133 if (!vma)
1134 return 0;
1135
1136 return (addr >= vma->vm_start) && (addr < vma->vm_end);
1137 }
1138
1139 /*
1140 * Use this when you have no reliable task/vma, typically from interrupt
1141 * context. It is less reliable than using the task's vma and may give
1142 * false positives:
1143 */
1144 int in_gate_area_no_task(unsigned long addr)
1145 {
1146 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1147 }
1148
1149 const char *arch_vma_name(struct vm_area_struct *vma)
1150 {
1151 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1152 return "[vdso]";
1153 if (vma == &gate_vma)
1154 return "[vsyscall]";
1155 return NULL;
1156 }
1157
1158 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1159 /*
1160 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1161 */
1162 static long __meminitdata addr_start, addr_end;
1163 static void __meminitdata *p_start, *p_end;
1164 static int __meminitdata node_start;
1165
1166 int __meminit
1167 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1168 {
1169 unsigned long addr = (unsigned long)start_page;
1170 unsigned long end = (unsigned long)(start_page + size);
1171 unsigned long next;
1172 pgd_t *pgd;
1173 pud_t *pud;
1174 pmd_t *pmd;
1175
1176 for (; addr < end; addr = next) {
1177 void *p = NULL;
1178
1179 pgd = vmemmap_pgd_populate(addr, node);
1180 if (!pgd)
1181 return -ENOMEM;
1182
1183 pud = vmemmap_pud_populate(pgd, addr, node);
1184 if (!pud)
1185 return -ENOMEM;
1186
1187 if (!cpu_has_pse) {
1188 next = (addr + PAGE_SIZE) & PAGE_MASK;
1189 pmd = vmemmap_pmd_populate(pud, addr, node);
1190
1191 if (!pmd)
1192 return -ENOMEM;
1193
1194 p = vmemmap_pte_populate(pmd, addr, node);
1195
1196 if (!p)
1197 return -ENOMEM;
1198
1199 addr_end = addr + PAGE_SIZE;
1200 p_end = p + PAGE_SIZE;
1201 } else {
1202 next = pmd_addr_end(addr, end);
1203
1204 pmd = pmd_offset(pud, addr);
1205 if (pmd_none(*pmd)) {
1206 pte_t entry;
1207
1208 p = vmemmap_alloc_block(PMD_SIZE, node);
1209 if (!p)
1210 return -ENOMEM;
1211
1212 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1213 PAGE_KERNEL_LARGE);
1214 set_pmd(pmd, __pmd(pte_val(entry)));
1215
1216 /* check to see if we have contiguous blocks */
1217 if (p_end != p || node_start != node) {
1218 if (p_start)
1219 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1220 addr_start, addr_end-1, p_start, p_end-1, node_start);
1221 addr_start = addr;
1222 node_start = node;
1223 p_start = p;
1224 }
1225
1226 addr_end = addr + PMD_SIZE;
1227 p_end = p + PMD_SIZE;
1228 } else
1229 vmemmap_verify((pte_t *)pmd, node, addr, next);
1230 }
1231
1232 }
1233 return 0;
1234 }
1235
1236 void __meminit vmemmap_populate_print_last(void)
1237 {
1238 if (p_start) {
1239 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1240 addr_start, addr_end-1, p_start, p_end-1, node_start);
1241 p_start = NULL;
1242 p_end = NULL;
1243 node_start = 0;
1244 }
1245 }
1246 #endif
linux 2.6 git repository for openrd