x86: 64 bit print out absent pages num too
[linux-2.6] / 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/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 void
172 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
173 {
174         pud_t *pud;
175         pmd_t *pmd;
176         pte_t *pte;
177
178         pud = pud_page + pud_index(vaddr);
179         if (pud_none(*pud)) {
180                 pmd = (pmd_t *) spp_getpage();
181                 pud_populate(&init_mm, pud, pmd);
182                 if (pmd != pmd_offset(pud, 0)) {
183                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
184                                 pmd, pmd_offset(pud, 0));
185                         return;
186                 }
187         }
188         pmd = pmd_offset(pud, vaddr);
189         if (pmd_none(*pmd)) {
190                 pte = (pte_t *) spp_getpage();
191                 pmd_populate_kernel(&init_mm, pmd, pte);
192                 if (pte != pte_offset_kernel(pmd, 0)) {
193                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
194                         return;
195                 }
196         }
197
198         pte = pte_offset_kernel(pmd, vaddr);
199         set_pte(pte, new_pte);
200
201         /*
202          * It's enough to flush this one mapping.
203          * (PGE mappings get flushed as well)
204          */
205         __flush_tlb_one(vaddr);
206 }
207
208 void
209 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
210 {
211         pgd_t *pgd;
212         pud_t *pud_page;
213
214         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
215
216         pgd = pgd_offset_k(vaddr);
217         if (pgd_none(*pgd)) {
218                 printk(KERN_ERR
219                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
220                 return;
221         }
222         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
223         set_pte_vaddr_pud(pud_page, vaddr, pteval);
224 }
225
226 /*
227  * Create large page table mappings for a range of physical addresses.
228  */
229 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
230                                                 pgprot_t prot)
231 {
232         pgd_t *pgd;
233         pud_t *pud;
234         pmd_t *pmd;
235
236         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
237         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
238                 pgd = pgd_offset_k((unsigned long)__va(phys));
239                 if (pgd_none(*pgd)) {
240                         pud = (pud_t *) spp_getpage();
241                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
242                                                 _PAGE_USER));
243                 }
244                 pud = pud_offset(pgd, (unsigned long)__va(phys));
245                 if (pud_none(*pud)) {
246                         pmd = (pmd_t *) spp_getpage();
247                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
248                                                 _PAGE_USER));
249                 }
250                 pmd = pmd_offset(pud, phys);
251                 BUG_ON(!pmd_none(*pmd));
252                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
253         }
254 }
255
256 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
257 {
258         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
259 }
260
261 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
262 {
263         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
264 }
265
266 /*
267  * The head.S code sets up the kernel high mapping:
268  *
269  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
270  *
271  * phys_addr holds the negative offset to the kernel, which is added
272  * to the compile time generated pmds. This results in invalid pmds up
273  * to the point where we hit the physaddr 0 mapping.
274  *
275  * We limit the mappings to the region from _text to _end.  _end is
276  * rounded up to the 2MB boundary. This catches the invalid pmds as
277  * well, as they are located before _text:
278  */
279 void __init cleanup_highmap(void)
280 {
281         unsigned long vaddr = __START_KERNEL_map;
282         unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
283         pmd_t *pmd = level2_kernel_pgt;
284         pmd_t *last_pmd = pmd + PTRS_PER_PMD;
285
286         for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
287                 if (pmd_none(*pmd))
288                         continue;
289                 if (vaddr < (unsigned long) _text || vaddr > end)
290                         set_pmd(pmd, __pmd(0));
291         }
292 }
293
294 static unsigned long __initdata table_start;
295 static unsigned long __meminitdata table_end;
296 static unsigned long __meminitdata table_top;
297
298 static __ref void *alloc_low_page(unsigned long *phys)
299 {
300         unsigned long pfn = table_end++;
301         void *adr;
302
303         if (after_bootmem) {
304                 adr = (void *)get_zeroed_page(GFP_ATOMIC);
305                 *phys = __pa(adr);
306
307                 return adr;
308         }
309
310         if (pfn >= table_top)
311                 panic("alloc_low_page: ran out of memory");
312
313         adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
314         memset(adr, 0, PAGE_SIZE);
315         *phys  = pfn * PAGE_SIZE;
316         return adr;
317 }
318
319 static __ref void unmap_low_page(void *adr)
320 {
321         if (after_bootmem)
322                 return;
323
324         early_iounmap(adr, PAGE_SIZE);
325 }
326
327 static unsigned long __meminit
328 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
329               pgprot_t prot)
330 {
331         unsigned pages = 0;
332         unsigned long last_map_addr = end;
333         int i;
334
335         pte_t *pte = pte_page + pte_index(addr);
336
337         for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
338
339                 if (addr >= end) {
340                         if (!after_bootmem) {
341                                 for(; i < PTRS_PER_PTE; i++, pte++)
342                                         set_pte(pte, __pte(0));
343                         }
344                         break;
345                 }
346
347                 /*
348                  * We will re-use the existing mapping.
349                  * Xen for example has some special requirements, like mapping
350                  * pagetable pages as RO. So assume someone who pre-setup
351                  * these mappings are more intelligent.
352                  */
353                 if (pte_val(*pte)) {
354                         pages++;
355                         continue;
356                 }
357
358                 if (0)
359                         printk("   pte=%p addr=%lx pte=%016lx\n",
360                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
361                 pages++;
362                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
363                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
364         }
365
366         update_page_count(PG_LEVEL_4K, pages);
367
368         return last_map_addr;
369 }
370
371 static unsigned long __meminit
372 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
373                 pgprot_t prot)
374 {
375         pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
376
377         return phys_pte_init(pte, address, end, prot);
378 }
379
380 static unsigned long __meminit
381 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
382               unsigned long page_size_mask, pgprot_t prot)
383 {
384         unsigned long pages = 0;
385         unsigned long last_map_addr = end;
386
387         int i = pmd_index(address);
388
389         for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
390                 unsigned long pte_phys;
391                 pmd_t *pmd = pmd_page + pmd_index(address);
392                 pte_t *pte;
393                 pgprot_t new_prot = prot;
394
395                 if (address >= end) {
396                         if (!after_bootmem) {
397                                 for (; i < PTRS_PER_PMD; i++, pmd++)
398                                         set_pmd(pmd, __pmd(0));
399                         }
400                         break;
401                 }
402
403                 if (pmd_val(*pmd)) {
404                         if (!pmd_large(*pmd)) {
405                                 spin_lock(&init_mm.page_table_lock);
406                                 last_map_addr = phys_pte_update(pmd, address,
407                                                                 end, prot);
408                                 spin_unlock(&init_mm.page_table_lock);
409                                 continue;
410                         }
411                         /*
412                          * If we are ok with PG_LEVEL_2M mapping, then we will
413                          * use the existing mapping,
414                          *
415                          * Otherwise, we will split the large page mapping but
416                          * use the same existing protection bits except for
417                          * large page, so that we don't violate Intel's TLB
418                          * Application note (317080) which says, while changing
419                          * the page sizes, new and old translations should
420                          * not differ with respect to page frame and
421                          * attributes.
422                          */
423                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
424                                 pages++;
425                                 continue;
426                         }
427                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
428                 }
429
430                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
431                         pages++;
432                         spin_lock(&init_mm.page_table_lock);
433                         set_pte((pte_t *)pmd,
434                                 pfn_pte(address >> PAGE_SHIFT,
435                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
436                         spin_unlock(&init_mm.page_table_lock);
437                         last_map_addr = (address & PMD_MASK) + PMD_SIZE;
438                         continue;
439                 }
440
441                 pte = alloc_low_page(&pte_phys);
442                 last_map_addr = phys_pte_init(pte, address, end, new_prot);
443                 unmap_low_page(pte);
444
445                 spin_lock(&init_mm.page_table_lock);
446                 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
447                 spin_unlock(&init_mm.page_table_lock);
448         }
449         update_page_count(PG_LEVEL_2M, pages);
450         return last_map_addr;
451 }
452
453 static unsigned long __meminit
454 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
455                 unsigned long page_size_mask, pgprot_t prot)
456 {
457         pmd_t *pmd = pmd_offset(pud, 0);
458         unsigned long last_map_addr;
459
460         last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
461         __flush_tlb_all();
462         return last_map_addr;
463 }
464
465 static unsigned long __meminit
466 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
467                          unsigned long page_size_mask)
468 {
469         unsigned long pages = 0;
470         unsigned long last_map_addr = end;
471         int i = pud_index(addr);
472
473         for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
474                 unsigned long pmd_phys;
475                 pud_t *pud = pud_page + pud_index(addr);
476                 pmd_t *pmd;
477                 pgprot_t prot = PAGE_KERNEL;
478
479                 if (addr >= end)
480                         break;
481
482                 if (!after_bootmem &&
483                                 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
484                         set_pud(pud, __pud(0));
485                         continue;
486                 }
487
488                 if (pud_val(*pud)) {
489                         if (!pud_large(*pud)) {
490                                 last_map_addr = phys_pmd_update(pud, addr, end,
491                                                          page_size_mask, prot);
492                                 continue;
493                         }
494                         /*
495                          * If we are ok with PG_LEVEL_1G mapping, then we will
496                          * use the existing mapping.
497                          *
498                          * Otherwise, we will split the gbpage mapping but use
499                          * the same existing protection  bits except for large
500                          * page, so that we don't violate Intel's TLB
501                          * Application note (317080) which says, while changing
502                          * the page sizes, new and old translations should
503                          * not differ with respect to page frame and
504                          * attributes.
505                          */
506                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
507                                 pages++;
508                                 continue;
509                         }
510                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
511                 }
512
513                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
514                         pages++;
515                         spin_lock(&init_mm.page_table_lock);
516                         set_pte((pte_t *)pud,
517                                 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
518                         spin_unlock(&init_mm.page_table_lock);
519                         last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
520                         continue;
521                 }
522
523                 pmd = alloc_low_page(&pmd_phys);
524                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
525                                               prot);
526                 unmap_low_page(pmd);
527
528                 spin_lock(&init_mm.page_table_lock);
529                 pud_populate(&init_mm, pud, __va(pmd_phys));
530                 spin_unlock(&init_mm.page_table_lock);
531         }
532         __flush_tlb_all();
533
534         update_page_count(PG_LEVEL_1G, pages);
535
536         return last_map_addr;
537 }
538
539 static unsigned long __meminit
540 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
541                  unsigned long page_size_mask)
542 {
543         pud_t *pud;
544
545         pud = (pud_t *)pgd_page_vaddr(*pgd);
546
547         return phys_pud_init(pud, addr, end, page_size_mask);
548 }
549
550 static void __init find_early_table_space(unsigned long end, int use_pse,
551                                           int use_gbpages)
552 {
553         unsigned long puds, pmds, ptes, tables, start;
554
555         puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
556         tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
557         if (use_gbpages) {
558                 unsigned long extra;
559                 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
560                 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
561         } else
562                 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
563         tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
564
565         if (use_pse) {
566                 unsigned long extra;
567                 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
568                 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
569         } else
570                 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
571         tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
572
573         /*
574          * RED-PEN putting page tables only on node 0 could
575          * cause a hotspot and fill up ZONE_DMA. The page tables
576          * need roughly 0.5KB per GB.
577          */
578         start = 0x8000;
579         table_start = find_e820_area(start, end, tables, PAGE_SIZE);
580         if (table_start == -1UL)
581                 panic("Cannot find space for the kernel page tables");
582
583         table_start >>= PAGE_SHIFT;
584         table_end = table_start;
585         table_top = table_start + (tables >> PAGE_SHIFT);
586
587         printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
588                 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
589 }
590
591 static void __init init_gbpages(void)
592 {
593         if (direct_gbpages && cpu_has_gbpages)
594                 printk(KERN_INFO "Using GB pages for direct mapping\n");
595         else
596                 direct_gbpages = 0;
597 }
598
599 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
600                                                 unsigned long end,
601                                                 unsigned long page_size_mask)
602 {
603
604         unsigned long next, last_map_addr = end;
605
606         start = (unsigned long)__va(start);
607         end = (unsigned long)__va(end);
608
609         for (; start < end; start = next) {
610                 pgd_t *pgd = pgd_offset_k(start);
611                 unsigned long pud_phys;
612                 pud_t *pud;
613
614                 next = (start + PGDIR_SIZE) & PGDIR_MASK;
615                 if (next > end)
616                         next = end;
617
618                 if (pgd_val(*pgd)) {
619                         last_map_addr = phys_pud_update(pgd, __pa(start),
620                                                  __pa(end), page_size_mask);
621                         continue;
622                 }
623
624                 pud = alloc_low_page(&pud_phys);
625                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
626                                                  page_size_mask);
627                 unmap_low_page(pud);
628
629                 spin_lock(&init_mm.page_table_lock);
630                 pgd_populate(&init_mm, pgd, __va(pud_phys));
631                 spin_unlock(&init_mm.page_table_lock);
632         }
633         __flush_tlb_all();
634
635         return last_map_addr;
636 }
637
638 struct map_range {
639         unsigned long start;
640         unsigned long end;
641         unsigned page_size_mask;
642 };
643
644 #define NR_RANGE_MR 5
645
646 static int save_mr(struct map_range *mr, int nr_range,
647                    unsigned long start_pfn, unsigned long end_pfn,
648                    unsigned long page_size_mask)
649 {
650
651         if (start_pfn < end_pfn) {
652                 if (nr_range >= NR_RANGE_MR)
653                         panic("run out of range for init_memory_mapping\n");
654                 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
655                 mr[nr_range].end   = end_pfn<<PAGE_SHIFT;
656                 mr[nr_range].page_size_mask = page_size_mask;
657                 nr_range++;
658         }
659
660         return nr_range;
661 }
662
663 /*
664  * Setup the direct mapping of the physical memory at PAGE_OFFSET.
665  * This runs before bootmem is initialized and gets pages directly from
666  * the physical memory. To access them they are temporarily mapped.
667  */
668 unsigned long __init_refok init_memory_mapping(unsigned long start,
669                                                unsigned long end)
670 {
671         unsigned long last_map_addr = 0;
672         unsigned long page_size_mask = 0;
673         unsigned long start_pfn, end_pfn;
674
675         struct map_range mr[NR_RANGE_MR];
676         int nr_range, i;
677         int use_pse, use_gbpages;
678
679         printk(KERN_INFO "init_memory_mapping\n");
680
681         /*
682          * Find space for the kernel direct mapping tables.
683          *
684          * Later we should allocate these tables in the local node of the
685          * memory mapped. Unfortunately this is done currently before the
686          * nodes are discovered.
687          */
688         if (!after_bootmem)
689                 init_gbpages();
690
691 #ifdef CONFIG_DEBUG_PAGEALLOC
692         /*
693          * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
694          * This will simplify cpa(), which otherwise needs to support splitting
695          * large pages into small in interrupt context, etc.
696          */
697         use_pse = use_gbpages = 0;
698 #else
699         use_pse = cpu_has_pse;
700         use_gbpages = direct_gbpages;
701 #endif
702
703         if (use_gbpages)
704                 page_size_mask |= 1 << PG_LEVEL_1G;
705         if (use_pse)
706                 page_size_mask |= 1 << PG_LEVEL_2M;
707
708         memset(mr, 0, sizeof(mr));
709         nr_range = 0;
710
711         /* head if not big page alignment ?*/
712         start_pfn = start >> PAGE_SHIFT;
713         end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
714                         << (PMD_SHIFT - PAGE_SHIFT);
715         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
716
717         /* big page (2M) range*/
718         start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
719                          << (PMD_SHIFT - PAGE_SHIFT);
720         end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
721                          << (PUD_SHIFT - PAGE_SHIFT);
722         if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
723                 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
724         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
725                         page_size_mask & (1<<PG_LEVEL_2M));
726
727         /* big page (1G) range */
728         start_pfn = end_pfn;
729         end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
730         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
731                                 page_size_mask &
732                                  ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
733
734         /* tail is not big page (1G) alignment */
735         start_pfn = end_pfn;
736         end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
737         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
738                         page_size_mask & (1<<PG_LEVEL_2M));
739
740         /* tail is not big page (2M) alignment */
741         start_pfn = end_pfn;
742         end_pfn = end>>PAGE_SHIFT;
743         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
744
745         /* try to merge same page size and continuous */
746         for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
747                 unsigned long old_start;
748                 if (mr[i].end != mr[i+1].start ||
749                     mr[i].page_size_mask != mr[i+1].page_size_mask)
750                         continue;
751                 /* move it */
752                 old_start = mr[i].start;
753                 memmove(&mr[i], &mr[i+1],
754                          (nr_range - 1 - i) * sizeof (struct map_range));
755                 mr[i--].start = old_start;
756                 nr_range--;
757         }
758
759         for (i = 0; i < nr_range; i++)
760                 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
761                                 mr[i].start, mr[i].end,
762                         (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
763                          (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
764
765         if (!after_bootmem)
766                 find_early_table_space(end, use_pse, use_gbpages);
767
768         for (i = 0; i < nr_range; i++)
769                 last_map_addr = kernel_physical_mapping_init(
770                                         mr[i].start, mr[i].end,
771                                         mr[i].page_size_mask);
772
773         if (!after_bootmem)
774                 mmu_cr4_features = read_cr4();
775         __flush_tlb_all();
776
777         if (!after_bootmem && table_end > table_start)
778                 reserve_early(table_start << PAGE_SHIFT,
779                                  table_end << PAGE_SHIFT, "PGTABLE");
780
781         printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
782                          last_map_addr, end);
783
784         if (!after_bootmem)
785                 early_memtest(start, end);
786
787         return last_map_addr >> PAGE_SHIFT;
788 }
789
790 #ifndef CONFIG_NUMA
791 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
792 {
793         unsigned long bootmap_size, bootmap;
794
795         bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
796         bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
797                                  PAGE_SIZE);
798         if (bootmap == -1L)
799                 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
800         /* don't touch min_low_pfn */
801         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
802                                          0, end_pfn);
803         e820_register_active_regions(0, start_pfn, end_pfn);
804         free_bootmem_with_active_regions(0, end_pfn);
805         early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
806         reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
807 }
808
809 void __init paging_init(void)
810 {
811         unsigned long max_zone_pfns[MAX_NR_ZONES];
812
813         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
814         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
815         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
816         max_zone_pfns[ZONE_NORMAL] = max_pfn;
817
818         memory_present(0, 0, max_pfn);
819         sparse_init();
820         free_area_init_nodes(max_zone_pfns);
821 }
822 #endif
823
824 /*
825  * Memory hotplug specific functions
826  */
827 #ifdef CONFIG_MEMORY_HOTPLUG
828 /*
829  * Memory is added always to NORMAL zone. This means you will never get
830  * additional DMA/DMA32 memory.
831  */
832 int arch_add_memory(int nid, u64 start, u64 size)
833 {
834         struct pglist_data *pgdat = NODE_DATA(nid);
835         struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
836         unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
837         unsigned long nr_pages = size >> PAGE_SHIFT;
838         int ret;
839
840         last_mapped_pfn = init_memory_mapping(start, start + size);
841         if (last_mapped_pfn > max_pfn_mapped)
842                 max_pfn_mapped = last_mapped_pfn;
843
844         ret = __add_pages(zone, start_pfn, nr_pages);
845         WARN_ON(1);
846
847         return ret;
848 }
849 EXPORT_SYMBOL_GPL(arch_add_memory);
850
851 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
852 int memory_add_physaddr_to_nid(u64 start)
853 {
854         return 0;
855 }
856 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
857 #endif
858
859 #endif /* CONFIG_MEMORY_HOTPLUG */
860
861 /*
862  * devmem_is_allowed() checks to see if /dev/mem access to a certain address
863  * is valid. The argument is a physical page number.
864  *
865  *
866  * On x86, access has to be given to the first megabyte of ram because that area
867  * contains bios code and data regions used by X and dosemu and similar apps.
868  * Access has to be given to non-kernel-ram areas as well, these contain the PCI
869  * mmio resources as well as potential bios/acpi data regions.
870  */
871 int devmem_is_allowed(unsigned long pagenr)
872 {
873         if (pagenr <= 256)
874                 return 1;
875         if (!page_is_ram(pagenr))
876                 return 1;
877         return 0;
878 }
879
880
881 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
882                          kcore_modules, kcore_vsyscall;
883
884 void __init mem_init(void)
885 {
886         long codesize, reservedpages, datasize, initsize;
887         unsigned long absent_pages;
888
889         start_periodic_check_for_corruption();
890
891         pci_iommu_alloc();
892
893         /* clear_bss() already clear the empty_zero_page */
894
895         reservedpages = 0;
896
897         /* this will put all low memory onto the freelists */
898 #ifdef CONFIG_NUMA
899         totalram_pages = numa_free_all_bootmem();
900 #else
901         totalram_pages = free_all_bootmem();
902 #endif
903
904         absent_pages = absent_pages_in_range(0, max_pfn);
905         reservedpages = max_pfn - totalram_pages - absent_pages;
906         after_bootmem = 1;
907
908         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
909         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
910         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
911
912         /* Register memory areas for /proc/kcore */
913         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
914         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
915                    VMALLOC_END-VMALLOC_START);
916         kclist_add(&kcore_kernel, &_stext, _end - _stext);
917         kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
918         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
919                                  VSYSCALL_END - VSYSCALL_START);
920
921         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
922                          "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
923                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
924                 max_pfn << (PAGE_SHIFT-10),
925                 codesize >> 10,
926                 absent_pages << (PAGE_SHIFT-10),
927                 reservedpages << (PAGE_SHIFT-10),
928                 datasize >> 10,
929                 initsize >> 10);
930 }
931
932 void free_init_pages(char *what, unsigned long begin, unsigned long end)
933 {
934         unsigned long addr = begin;
935
936         if (addr >= end)
937                 return;
938
939         /*
940          * If debugging page accesses then do not free this memory but
941          * mark them not present - any buggy init-section access will
942          * create a kernel page fault:
943          */
944 #ifdef CONFIG_DEBUG_PAGEALLOC
945         printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
946                 begin, PAGE_ALIGN(end));
947         set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
948 #else
949         printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
950
951         for (; addr < end; addr += PAGE_SIZE) {
952                 ClearPageReserved(virt_to_page(addr));
953                 init_page_count(virt_to_page(addr));
954                 memset((void *)(addr & ~(PAGE_SIZE-1)),
955                         POISON_FREE_INITMEM, PAGE_SIZE);
956                 free_page(addr);
957                 totalram_pages++;
958         }
959 #endif
960 }
961
962 void free_initmem(void)
963 {
964         free_init_pages("unused kernel memory",
965                         (unsigned long)(&__init_begin),
966                         (unsigned long)(&__init_end));
967 }
968
969 #ifdef CONFIG_DEBUG_RODATA
970 const int rodata_test_data = 0xC3;
971 EXPORT_SYMBOL_GPL(rodata_test_data);
972
973 void mark_rodata_ro(void)
974 {
975         unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
976         unsigned long rodata_start =
977                 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
978
979 #ifdef CONFIG_DYNAMIC_FTRACE
980         /* Dynamic tracing modifies the kernel text section */
981         start = rodata_start;
982 #endif
983
984         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
985                (end - start) >> 10);
986         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
987
988         /*
989          * The rodata section (but not the kernel text!) should also be
990          * not-executable.
991          */
992         set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
993
994         rodata_test();
995
996 #ifdef CONFIG_CPA_DEBUG
997         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
998         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
999
1000         printk(KERN_INFO "Testing CPA: again\n");
1001         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1002 #endif
1003 }
1004
1005 #endif
1006
1007 #ifdef CONFIG_BLK_DEV_INITRD
1008 void free_initrd_mem(unsigned long start, unsigned long end)
1009 {
1010         free_init_pages("initrd memory", start, end);
1011 }
1012 #endif
1013
1014 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
1015                                    int flags)
1016 {
1017 #ifdef CONFIG_NUMA
1018         int nid, next_nid;
1019         int ret;
1020 #endif
1021         unsigned long pfn = phys >> PAGE_SHIFT;
1022
1023         if (pfn >= max_pfn) {
1024                 /*
1025                  * This can happen with kdump kernels when accessing
1026                  * firmware tables:
1027                  */
1028                 if (pfn < max_pfn_mapped)
1029                         return -EFAULT;
1030
1031                 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
1032                                 phys, len);
1033                 return -EFAULT;
1034         }
1035
1036         /* Should check here against the e820 map to avoid double free */
1037 #ifdef CONFIG_NUMA
1038         nid = phys_to_nid(phys);
1039         next_nid = phys_to_nid(phys + len - 1);
1040         if (nid == next_nid)
1041                 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
1042         else
1043                 ret = reserve_bootmem(phys, len, flags);
1044
1045         if (ret != 0)
1046                 return ret;
1047
1048 #else
1049         reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
1050 #endif
1051
1052         if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
1053                 dma_reserve += len / PAGE_SIZE;
1054                 set_dma_reserve(dma_reserve);
1055         }
1056
1057         return 0;
1058 }
1059
1060 int kern_addr_valid(unsigned long addr)
1061 {
1062         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1063         pgd_t *pgd;
1064         pud_t *pud;
1065         pmd_t *pmd;
1066         pte_t *pte;
1067
1068         if (above != 0 && above != -1UL)
1069                 return 0;
1070
1071         pgd = pgd_offset_k(addr);
1072         if (pgd_none(*pgd))
1073                 return 0;
1074
1075         pud = pud_offset(pgd, addr);
1076         if (pud_none(*pud))
1077                 return 0;
1078
1079         pmd = pmd_offset(pud, addr);
1080         if (pmd_none(*pmd))
1081                 return 0;
1082
1083         if (pmd_large(*pmd))
1084                 return pfn_valid(pmd_pfn(*pmd));
1085
1086         pte = pte_offset_kernel(pmd, addr);
1087         if (pte_none(*pte))
1088                 return 0;
1089
1090         return pfn_valid(pte_pfn(*pte));
1091 }
1092
1093 /*
1094  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
1095  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1096  * not need special handling anymore:
1097  */
1098 static struct vm_area_struct gate_vma = {
1099         .vm_start       = VSYSCALL_START,
1100         .vm_end         = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1101         .vm_page_prot   = PAGE_READONLY_EXEC,
1102         .vm_flags       = VM_READ | VM_EXEC
1103 };
1104
1105 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
1106 {
1107 #ifdef CONFIG_IA32_EMULATION
1108         if (test_tsk_thread_flag(tsk, TIF_IA32))
1109                 return NULL;
1110 #endif
1111         return &gate_vma;
1112 }
1113
1114 int in_gate_area(struct task_struct *task, unsigned long addr)
1115 {
1116         struct vm_area_struct *vma = get_gate_vma(task);
1117
1118         if (!vma)
1119                 return 0;
1120
1121         return (addr >= vma->vm_start) && (addr < vma->vm_end);
1122 }
1123
1124 /*
1125  * Use this when you have no reliable task/vma, typically from interrupt
1126  * context. It is less reliable than using the task's vma and may give
1127  * false positives:
1128  */
1129 int in_gate_area_no_task(unsigned long addr)
1130 {
1131         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1132 }
1133
1134 const char *arch_vma_name(struct vm_area_struct *vma)
1135 {
1136         if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1137                 return "[vdso]";
1138         if (vma == &gate_vma)
1139                 return "[vsyscall]";
1140         return NULL;
1141 }
1142
1143 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1144 /*
1145  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1146  */
1147 static long __meminitdata addr_start, addr_end;
1148 static void __meminitdata *p_start, *p_end;
1149 static int __meminitdata node_start;
1150
1151 int __meminit
1152 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1153 {
1154         unsigned long addr = (unsigned long)start_page;
1155         unsigned long end = (unsigned long)(start_page + size);
1156         unsigned long next;
1157         pgd_t *pgd;
1158         pud_t *pud;
1159         pmd_t *pmd;
1160
1161         for (; addr < end; addr = next) {
1162                 void *p = NULL;
1163
1164                 pgd = vmemmap_pgd_populate(addr, node);
1165                 if (!pgd)
1166                         return -ENOMEM;
1167
1168                 pud = vmemmap_pud_populate(pgd, addr, node);
1169                 if (!pud)
1170                         return -ENOMEM;
1171
1172                 if (!cpu_has_pse) {
1173                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1174                         pmd = vmemmap_pmd_populate(pud, addr, node);
1175
1176                         if (!pmd)
1177                                 return -ENOMEM;
1178
1179                         p = vmemmap_pte_populate(pmd, addr, node);
1180
1181                         if (!p)
1182                                 return -ENOMEM;
1183
1184                         addr_end = addr + PAGE_SIZE;
1185                         p_end = p + PAGE_SIZE;
1186                 } else {
1187                         next = pmd_addr_end(addr, end);
1188
1189                         pmd = pmd_offset(pud, addr);
1190                         if (pmd_none(*pmd)) {
1191                                 pte_t entry;
1192
1193                                 p = vmemmap_alloc_block(PMD_SIZE, node);
1194                                 if (!p)
1195                                         return -ENOMEM;
1196
1197                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1198                                                 PAGE_KERNEL_LARGE);
1199                                 set_pmd(pmd, __pmd(pte_val(entry)));
1200
1201                                 /* check to see if we have contiguous blocks */
1202                                 if (p_end != p || node_start != node) {
1203                                         if (p_start)
1204                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1205                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1206                                         addr_start = addr;
1207                                         node_start = node;
1208                                         p_start = p;
1209                                 }
1210
1211                                 addr_end = addr + PMD_SIZE;
1212                                 p_end = p + PMD_SIZE;
1213                         } else
1214                                 vmemmap_verify((pte_t *)pmd, node, addr, next);
1215                 }
1216
1217         }
1218         return 0;
1219 }
1220
1221 void __meminit vmemmap_populate_print_last(void)
1222 {
1223         if (p_start) {
1224                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1225                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1226                 p_start = NULL;
1227                 p_end = NULL;
1228                 node_start = 0;
1229         }
1230 }
1231 #endif