Merge branch 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[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/system.h>
35 #include <asm/uaccess.h>
36 #include <asm/pgtable.h>
37 #include <asm/pgalloc.h>
38 #include <asm/dma.h>
39 #include <asm/fixmap.h>
40 #include <asm/e820.h>
41 #include <asm/apic.h>
42 #include <asm/tlb.h>
43 #include <asm/mmu_context.h>
44 #include <asm/proto.h>
45 #include <asm/smp.h>
46 #include <asm/sections.h>
47 #include <asm/kdebug.h>
48 #include <asm/numa.h>
49 #include <asm/cacheflush.h>
50
51 /*
52  * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
53  * The direct mapping extends to max_pfn_mapped, so that we can directly access
54  * apertures, ACPI and other tables without having to play with fixmaps.
55  */
56 unsigned long max_low_pfn_mapped;
57 unsigned long max_pfn_mapped;
58
59 static unsigned long dma_reserve __initdata;
60
61 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
62
63 int direct_gbpages
64 #ifdef CONFIG_DIRECT_GBPAGES
65                                 = 1
66 #endif
67 ;
68
69 static int __init parse_direct_gbpages_off(char *arg)
70 {
71         direct_gbpages = 0;
72         return 0;
73 }
74 early_param("nogbpages", parse_direct_gbpages_off);
75
76 static int __init parse_direct_gbpages_on(char *arg)
77 {
78         direct_gbpages = 1;
79         return 0;
80 }
81 early_param("gbpages", parse_direct_gbpages_on);
82
83 /*
84  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
85  * physical space so we can cache the place of the first one and move
86  * around without checking the pgd every time.
87  */
88
89 int after_bootmem;
90
91 /*
92  * NOTE: This function is marked __ref because it calls __init function
93  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
94  */
95 static __ref void *spp_getpage(void)
96 {
97         void *ptr;
98
99         if (after_bootmem)
100                 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
101         else
102                 ptr = alloc_bootmem_pages(PAGE_SIZE);
103
104         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
105                 panic("set_pte_phys: cannot allocate page data %s\n",
106                         after_bootmem ? "after bootmem" : "");
107         }
108
109         pr_debug("spp_getpage %p\n", ptr);
110
111         return ptr;
112 }
113
114 void
115 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
116 {
117         pud_t *pud;
118         pmd_t *pmd;
119         pte_t *pte;
120
121         pud = pud_page + pud_index(vaddr);
122         if (pud_none(*pud)) {
123                 pmd = (pmd_t *) spp_getpage();
124                 pud_populate(&init_mm, pud, pmd);
125                 if (pmd != pmd_offset(pud, 0)) {
126                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
127                                 pmd, pmd_offset(pud, 0));
128                         return;
129                 }
130         }
131         pmd = pmd_offset(pud, vaddr);
132         if (pmd_none(*pmd)) {
133                 pte = (pte_t *) spp_getpage();
134                 pmd_populate_kernel(&init_mm, pmd, pte);
135                 if (pte != pte_offset_kernel(pmd, 0)) {
136                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
137                         return;
138                 }
139         }
140
141         pte = pte_offset_kernel(pmd, vaddr);
142         if (!pte_none(*pte) && pte_val(new_pte) &&
143             pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
144                 pte_ERROR(*pte);
145         set_pte(pte, new_pte);
146
147         /*
148          * It's enough to flush this one mapping.
149          * (PGE mappings get flushed as well)
150          */
151         __flush_tlb_one(vaddr);
152 }
153
154 void
155 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
156 {
157         pgd_t *pgd;
158         pud_t *pud_page;
159
160         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
161
162         pgd = pgd_offset_k(vaddr);
163         if (pgd_none(*pgd)) {
164                 printk(KERN_ERR
165                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
166                 return;
167         }
168         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
169         set_pte_vaddr_pud(pud_page, vaddr, pteval);
170 }
171
172 /*
173  * Create large page table mappings for a range of physical addresses.
174  */
175 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
176                                                 pgprot_t prot)
177 {
178         pgd_t *pgd;
179         pud_t *pud;
180         pmd_t *pmd;
181
182         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
183         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
184                 pgd = pgd_offset_k((unsigned long)__va(phys));
185                 if (pgd_none(*pgd)) {
186                         pud = (pud_t *) spp_getpage();
187                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
188                                                 _PAGE_USER));
189                 }
190                 pud = pud_offset(pgd, (unsigned long)__va(phys));
191                 if (pud_none(*pud)) {
192                         pmd = (pmd_t *) spp_getpage();
193                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
194                                                 _PAGE_USER));
195                 }
196                 pmd = pmd_offset(pud, phys);
197                 BUG_ON(!pmd_none(*pmd));
198                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
199         }
200 }
201
202 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
203 {
204         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
205 }
206
207 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
208 {
209         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
210 }
211
212 /*
213  * The head.S code sets up the kernel high mapping:
214  *
215  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
216  *
217  * phys_addr holds the negative offset to the kernel, which is added
218  * to the compile time generated pmds. This results in invalid pmds up
219  * to the point where we hit the physaddr 0 mapping.
220  *
221  * We limit the mappings to the region from _text to _end.  _end is
222  * rounded up to the 2MB boundary. This catches the invalid pmds as
223  * well, as they are located before _text:
224  */
225 void __init cleanup_highmap(void)
226 {
227         unsigned long vaddr = __START_KERNEL_map;
228         unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
229         pmd_t *pmd = level2_kernel_pgt;
230         pmd_t *last_pmd = pmd + PTRS_PER_PMD;
231
232         for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
233                 if (pmd_none(*pmd))
234                         continue;
235                 if (vaddr < (unsigned long) _text || vaddr > end)
236                         set_pmd(pmd, __pmd(0));
237         }
238 }
239
240 static unsigned long __initdata table_start;
241 static unsigned long __meminitdata table_end;
242 static unsigned long __meminitdata table_top;
243
244 static __ref void *alloc_low_page(unsigned long *phys)
245 {
246         unsigned long pfn = table_end++;
247         void *adr;
248
249         if (after_bootmem) {
250                 adr = (void *)get_zeroed_page(GFP_ATOMIC);
251                 *phys = __pa(adr);
252
253                 return adr;
254         }
255
256         if (pfn >= table_top)
257                 panic("alloc_low_page: ran out of memory");
258
259         adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
260         memset(adr, 0, PAGE_SIZE);
261         *phys  = pfn * PAGE_SIZE;
262         return adr;
263 }
264
265 static __ref void unmap_low_page(void *adr)
266 {
267         if (after_bootmem)
268                 return;
269
270         early_iounmap(adr, PAGE_SIZE);
271 }
272
273 static unsigned long __meminit
274 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end)
275 {
276         unsigned pages = 0;
277         unsigned long last_map_addr = end;
278         int i;
279
280         pte_t *pte = pte_page + pte_index(addr);
281
282         for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
283
284                 if (addr >= end) {
285                         if (!after_bootmem) {
286                                 for(; i < PTRS_PER_PTE; i++, pte++)
287                                         set_pte(pte, __pte(0));
288                         }
289                         break;
290                 }
291
292                 if (pte_val(*pte))
293                         continue;
294
295                 if (0)
296                         printk("   pte=%p addr=%lx pte=%016lx\n",
297                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
298                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL));
299                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
300                 pages++;
301         }
302         update_page_count(PG_LEVEL_4K, pages);
303
304         return last_map_addr;
305 }
306
307 static unsigned long __meminit
308 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end)
309 {
310         pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
311
312         return phys_pte_init(pte, address, end);
313 }
314
315 static unsigned long __meminit
316 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
317                          unsigned long page_size_mask)
318 {
319         unsigned long pages = 0;
320         unsigned long last_map_addr = end;
321         unsigned long start = address;
322
323         int i = pmd_index(address);
324
325         for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
326                 unsigned long pte_phys;
327                 pmd_t *pmd = pmd_page + pmd_index(address);
328                 pte_t *pte;
329
330                 if (address >= end) {
331                         if (!after_bootmem) {
332                                 for (; i < PTRS_PER_PMD; i++, pmd++)
333                                         set_pmd(pmd, __pmd(0));
334                         }
335                         break;
336                 }
337
338                 if (pmd_val(*pmd)) {
339                         if (!pmd_large(*pmd)) {
340                                 spin_lock(&init_mm.page_table_lock);
341                                 last_map_addr = phys_pte_update(pmd, address,
342                                                                 end);
343                                 spin_unlock(&init_mm.page_table_lock);
344                         }
345                         /* Count entries we're using from level2_ident_pgt */
346                         if (start == 0)
347                                 pages++;
348                         continue;
349                 }
350
351                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
352                         pages++;
353                         spin_lock(&init_mm.page_table_lock);
354                         set_pte((pte_t *)pmd,
355                                 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
356                         spin_unlock(&init_mm.page_table_lock);
357                         last_map_addr = (address & PMD_MASK) + PMD_SIZE;
358                         continue;
359                 }
360
361                 pte = alloc_low_page(&pte_phys);
362                 last_map_addr = phys_pte_init(pte, address, end);
363                 unmap_low_page(pte);
364
365                 spin_lock(&init_mm.page_table_lock);
366                 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
367                 spin_unlock(&init_mm.page_table_lock);
368         }
369         update_page_count(PG_LEVEL_2M, pages);
370         return last_map_addr;
371 }
372
373 static unsigned long __meminit
374 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
375                          unsigned long page_size_mask)
376 {
377         pmd_t *pmd = pmd_offset(pud, 0);
378         unsigned long last_map_addr;
379
380         last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask);
381         __flush_tlb_all();
382         return last_map_addr;
383 }
384
385 static unsigned long __meminit
386 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
387                          unsigned long page_size_mask)
388 {
389         unsigned long pages = 0;
390         unsigned long last_map_addr = end;
391         int i = pud_index(addr);
392
393         for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
394                 unsigned long pmd_phys;
395                 pud_t *pud = pud_page + pud_index(addr);
396                 pmd_t *pmd;
397
398                 if (addr >= end)
399                         break;
400
401                 if (!after_bootmem &&
402                                 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
403                         set_pud(pud, __pud(0));
404                         continue;
405                 }
406
407                 if (pud_val(*pud)) {
408                         if (!pud_large(*pud))
409                                 last_map_addr = phys_pmd_update(pud, addr, end,
410                                                          page_size_mask);
411                         continue;
412                 }
413
414                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
415                         pages++;
416                         spin_lock(&init_mm.page_table_lock);
417                         set_pte((pte_t *)pud,
418                                 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
419                         spin_unlock(&init_mm.page_table_lock);
420                         last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
421                         continue;
422                 }
423
424                 pmd = alloc_low_page(&pmd_phys);
425                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask);
426                 unmap_low_page(pmd);
427
428                 spin_lock(&init_mm.page_table_lock);
429                 pud_populate(&init_mm, pud, __va(pmd_phys));
430                 spin_unlock(&init_mm.page_table_lock);
431         }
432         __flush_tlb_all();
433         update_page_count(PG_LEVEL_1G, pages);
434
435         return last_map_addr;
436 }
437
438 static unsigned long __meminit
439 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
440                  unsigned long page_size_mask)
441 {
442         pud_t *pud;
443
444         pud = (pud_t *)pgd_page_vaddr(*pgd);
445
446         return phys_pud_init(pud, addr, end, page_size_mask);
447 }
448
449 static void __init find_early_table_space(unsigned long end)
450 {
451         unsigned long puds, pmds, ptes, tables, start;
452
453         puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
454         tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
455         if (direct_gbpages) {
456                 unsigned long extra;
457                 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
458                 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
459         } else
460                 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
461         tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
462
463         if (cpu_has_pse) {
464                 unsigned long extra;
465                 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
466                 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
467         } else
468                 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
469         tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
470
471         /*
472          * RED-PEN putting page tables only on node 0 could
473          * cause a hotspot and fill up ZONE_DMA. The page tables
474          * need roughly 0.5KB per GB.
475          */
476         start = 0x8000;
477         table_start = find_e820_area(start, end, tables, PAGE_SIZE);
478         if (table_start == -1UL)
479                 panic("Cannot find space for the kernel page tables");
480
481         table_start >>= PAGE_SHIFT;
482         table_end = table_start;
483         table_top = table_start + (tables >> PAGE_SHIFT);
484
485         printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
486                 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
487 }
488
489 static void __init init_gbpages(void)
490 {
491         if (direct_gbpages && cpu_has_gbpages)
492                 printk(KERN_INFO "Using GB pages for direct mapping\n");
493         else
494                 direct_gbpages = 0;
495 }
496
497 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
498                                                 unsigned long end,
499                                                 unsigned long page_size_mask)
500 {
501
502         unsigned long next, last_map_addr = end;
503
504         start = (unsigned long)__va(start);
505         end = (unsigned long)__va(end);
506
507         for (; start < end; start = next) {
508                 pgd_t *pgd = pgd_offset_k(start);
509                 unsigned long pud_phys;
510                 pud_t *pud;
511
512                 next = (start + PGDIR_SIZE) & PGDIR_MASK;
513                 if (next > end)
514                         next = end;
515
516                 if (pgd_val(*pgd)) {
517                         last_map_addr = phys_pud_update(pgd, __pa(start),
518                                                  __pa(end), page_size_mask);
519                         continue;
520                 }
521
522                 pud = alloc_low_page(&pud_phys);
523                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
524                                                  page_size_mask);
525                 unmap_low_page(pud);
526
527                 spin_lock(&init_mm.page_table_lock);
528                 pgd_populate(&init_mm, pgd, __va(pud_phys));
529                 spin_unlock(&init_mm.page_table_lock);
530         }
531
532         return last_map_addr;
533 }
534
535 struct map_range {
536         unsigned long start;
537         unsigned long end;
538         unsigned page_size_mask;
539 };
540
541 #define NR_RANGE_MR 5
542
543 static int save_mr(struct map_range *mr, int nr_range,
544                    unsigned long start_pfn, unsigned long end_pfn,
545                    unsigned long page_size_mask)
546 {
547
548         if (start_pfn < end_pfn) {
549                 if (nr_range >= NR_RANGE_MR)
550                         panic("run out of range for init_memory_mapping\n");
551                 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
552                 mr[nr_range].end   = end_pfn<<PAGE_SHIFT;
553                 mr[nr_range].page_size_mask = page_size_mask;
554                 nr_range++;
555         }
556
557         return nr_range;
558 }
559
560 /*
561  * Setup the direct mapping of the physical memory at PAGE_OFFSET.
562  * This runs before bootmem is initialized and gets pages directly from
563  * the physical memory. To access them they are temporarily mapped.
564  */
565 unsigned long __init_refok init_memory_mapping(unsigned long start,
566                                                unsigned long end)
567 {
568         unsigned long last_map_addr = 0;
569         unsigned long page_size_mask = 0;
570         unsigned long start_pfn, end_pfn;
571
572         struct map_range mr[NR_RANGE_MR];
573         int nr_range, i;
574
575         printk(KERN_INFO "init_memory_mapping\n");
576
577         /*
578          * Find space for the kernel direct mapping tables.
579          *
580          * Later we should allocate these tables in the local node of the
581          * memory mapped. Unfortunately this is done currently before the
582          * nodes are discovered.
583          */
584         if (!after_bootmem)
585                 init_gbpages();
586
587         if (direct_gbpages)
588                 page_size_mask |= 1 << PG_LEVEL_1G;
589         if (cpu_has_pse)
590                 page_size_mask |= 1 << PG_LEVEL_2M;
591
592         memset(mr, 0, sizeof(mr));
593         nr_range = 0;
594
595         /* head if not big page alignment ?*/
596         start_pfn = start >> PAGE_SHIFT;
597         end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
598                         << (PMD_SHIFT - PAGE_SHIFT);
599         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
600
601         /* big page (2M) range*/
602         start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
603                          << (PMD_SHIFT - PAGE_SHIFT);
604         end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
605                          << (PUD_SHIFT - PAGE_SHIFT);
606         if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
607                 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
608         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
609                         page_size_mask & (1<<PG_LEVEL_2M));
610
611         /* big page (1G) range */
612         start_pfn = end_pfn;
613         end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
614         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
615                                 page_size_mask &
616                                  ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
617
618         /* tail is not big page (1G) alignment */
619         start_pfn = end_pfn;
620         end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
621         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
622                         page_size_mask & (1<<PG_LEVEL_2M));
623
624         /* tail is not big page (2M) alignment */
625         start_pfn = end_pfn;
626         end_pfn = end>>PAGE_SHIFT;
627         nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
628
629         /* try to merge same page size and continuous */
630         for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
631                 unsigned long old_start;
632                 if (mr[i].end != mr[i+1].start ||
633                     mr[i].page_size_mask != mr[i+1].page_size_mask)
634                         continue;
635                 /* move it */
636                 old_start = mr[i].start;
637                 memmove(&mr[i], &mr[i+1],
638                          (nr_range - 1 - i) * sizeof (struct map_range));
639                 mr[i].start = old_start;
640                 nr_range--;
641         }
642
643         for (i = 0; i < nr_range; i++)
644                 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
645                                 mr[i].start, mr[i].end,
646                         (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
647                          (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
648
649         if (!after_bootmem)
650                 find_early_table_space(end);
651
652         for (i = 0; i < nr_range; i++)
653                 last_map_addr = kernel_physical_mapping_init(
654                                         mr[i].start, mr[i].end,
655                                         mr[i].page_size_mask);
656
657         if (!after_bootmem)
658                 mmu_cr4_features = read_cr4();
659         __flush_tlb_all();
660
661         if (!after_bootmem && table_end > table_start)
662                 reserve_early(table_start << PAGE_SHIFT,
663                                  table_end << PAGE_SHIFT, "PGTABLE");
664
665         printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
666                          last_map_addr, end);
667
668         if (!after_bootmem)
669                 early_memtest(start, end);
670
671         return last_map_addr >> PAGE_SHIFT;
672 }
673
674 #ifndef CONFIG_NUMA
675 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
676 {
677         unsigned long bootmap_size, bootmap;
678
679         bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
680         bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
681                                  PAGE_SIZE);
682         if (bootmap == -1L)
683                 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
684         /* don't touch min_low_pfn */
685         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
686                                          0, end_pfn);
687         e820_register_active_regions(0, start_pfn, end_pfn);
688         free_bootmem_with_active_regions(0, end_pfn);
689         early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
690         reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
691 }
692
693 void __init paging_init(void)
694 {
695         unsigned long max_zone_pfns[MAX_NR_ZONES];
696
697         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
698         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
699         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
700         max_zone_pfns[ZONE_NORMAL] = max_pfn;
701
702         memory_present(0, 0, max_pfn);
703         sparse_init();
704         free_area_init_nodes(max_zone_pfns);
705 }
706 #endif
707
708 /*
709  * Memory hotplug specific functions
710  */
711 #ifdef CONFIG_MEMORY_HOTPLUG
712 /*
713  * Memory is added always to NORMAL zone. This means you will never get
714  * additional DMA/DMA32 memory.
715  */
716 int arch_add_memory(int nid, u64 start, u64 size)
717 {
718         struct pglist_data *pgdat = NODE_DATA(nid);
719         struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
720         unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
721         unsigned long nr_pages = size >> PAGE_SHIFT;
722         int ret;
723
724         last_mapped_pfn = init_memory_mapping(start, start + size-1);
725         if (last_mapped_pfn > max_pfn_mapped)
726                 max_pfn_mapped = last_mapped_pfn;
727
728         ret = __add_pages(zone, start_pfn, nr_pages);
729         WARN_ON(1);
730
731         return ret;
732 }
733 EXPORT_SYMBOL_GPL(arch_add_memory);
734
735 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
736 int memory_add_physaddr_to_nid(u64 start)
737 {
738         return 0;
739 }
740 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
741 #endif
742
743 #endif /* CONFIG_MEMORY_HOTPLUG */
744
745 /*
746  * devmem_is_allowed() checks to see if /dev/mem access to a certain address
747  * is valid. The argument is a physical page number.
748  *
749  *
750  * On x86, access has to be given to the first megabyte of ram because that area
751  * contains bios code and data regions used by X and dosemu and similar apps.
752  * Access has to be given to non-kernel-ram areas as well, these contain the PCI
753  * mmio resources as well as potential bios/acpi data regions.
754  */
755 int devmem_is_allowed(unsigned long pagenr)
756 {
757         if (pagenr <= 256)
758                 return 1;
759         if (!page_is_ram(pagenr))
760                 return 1;
761         return 0;
762 }
763
764
765 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
766                          kcore_modules, kcore_vsyscall;
767
768 void __init mem_init(void)
769 {
770         long codesize, reservedpages, datasize, initsize;
771
772         pci_iommu_alloc();
773
774         /* clear_bss() already clear the empty_zero_page */
775
776         reservedpages = 0;
777
778         /* this will put all low memory onto the freelists */
779 #ifdef CONFIG_NUMA
780         totalram_pages = numa_free_all_bootmem();
781 #else
782         totalram_pages = free_all_bootmem();
783 #endif
784         reservedpages = max_pfn - totalram_pages -
785                                         absent_pages_in_range(0, max_pfn);
786         after_bootmem = 1;
787
788         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
789         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
790         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
791
792         /* Register memory areas for /proc/kcore */
793         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
794         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
795                    VMALLOC_END-VMALLOC_START);
796         kclist_add(&kcore_kernel, &_stext, _end - _stext);
797         kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
798         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
799                                  VSYSCALL_END - VSYSCALL_START);
800
801         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
802                                 "%ldk reserved, %ldk data, %ldk init)\n",
803                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
804                 max_pfn << (PAGE_SHIFT-10),
805                 codesize >> 10,
806                 reservedpages << (PAGE_SHIFT-10),
807                 datasize >> 10,
808                 initsize >> 10);
809
810         cpa_init();
811 }
812
813 void free_init_pages(char *what, unsigned long begin, unsigned long end)
814 {
815         unsigned long addr = begin;
816
817         if (addr >= end)
818                 return;
819
820         /*
821          * If debugging page accesses then do not free this memory but
822          * mark them not present - any buggy init-section access will
823          * create a kernel page fault:
824          */
825 #ifdef CONFIG_DEBUG_PAGEALLOC
826         printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
827                 begin, PAGE_ALIGN(end));
828         set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
829 #else
830         printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
831
832         for (; addr < end; addr += PAGE_SIZE) {
833                 ClearPageReserved(virt_to_page(addr));
834                 init_page_count(virt_to_page(addr));
835                 memset((void *)(addr & ~(PAGE_SIZE-1)),
836                         POISON_FREE_INITMEM, PAGE_SIZE);
837                 free_page(addr);
838                 totalram_pages++;
839         }
840 #endif
841 }
842
843 void free_initmem(void)
844 {
845         free_init_pages("unused kernel memory",
846                         (unsigned long)(&__init_begin),
847                         (unsigned long)(&__init_end));
848 }
849
850 #ifdef CONFIG_DEBUG_RODATA
851 const int rodata_test_data = 0xC3;
852 EXPORT_SYMBOL_GPL(rodata_test_data);
853
854 void mark_rodata_ro(void)
855 {
856         unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
857         unsigned long rodata_start =
858                 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
859
860 #ifdef CONFIG_DYNAMIC_FTRACE
861         /* Dynamic tracing modifies the kernel text section */
862         start = rodata_start;
863 #endif
864
865         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
866                (end - start) >> 10);
867         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
868
869         /*
870          * The rodata section (but not the kernel text!) should also be
871          * not-executable.
872          */
873         set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
874
875         rodata_test();
876
877 #ifdef CONFIG_CPA_DEBUG
878         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
879         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
880
881         printk(KERN_INFO "Testing CPA: again\n");
882         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
883 #endif
884 }
885
886 #endif
887
888 #ifdef CONFIG_BLK_DEV_INITRD
889 void free_initrd_mem(unsigned long start, unsigned long end)
890 {
891         free_init_pages("initrd memory", start, end);
892 }
893 #endif
894
895 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
896                                    int flags)
897 {
898 #ifdef CONFIG_NUMA
899         int nid, next_nid;
900         int ret;
901 #endif
902         unsigned long pfn = phys >> PAGE_SHIFT;
903
904         if (pfn >= max_pfn) {
905                 /*
906                  * This can happen with kdump kernels when accessing
907                  * firmware tables:
908                  */
909                 if (pfn < max_pfn_mapped)
910                         return -EFAULT;
911
912                 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
913                                 phys, len);
914                 return -EFAULT;
915         }
916
917         /* Should check here against the e820 map to avoid double free */
918 #ifdef CONFIG_NUMA
919         nid = phys_to_nid(phys);
920         next_nid = phys_to_nid(phys + len - 1);
921         if (nid == next_nid)
922                 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
923         else
924                 ret = reserve_bootmem(phys, len, flags);
925
926         if (ret != 0)
927                 return ret;
928
929 #else
930         reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
931 #endif
932
933         if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
934                 dma_reserve += len / PAGE_SIZE;
935                 set_dma_reserve(dma_reserve);
936         }
937
938         return 0;
939 }
940
941 int kern_addr_valid(unsigned long addr)
942 {
943         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
944         pgd_t *pgd;
945         pud_t *pud;
946         pmd_t *pmd;
947         pte_t *pte;
948
949         if (above != 0 && above != -1UL)
950                 return 0;
951
952         pgd = pgd_offset_k(addr);
953         if (pgd_none(*pgd))
954                 return 0;
955
956         pud = pud_offset(pgd, addr);
957         if (pud_none(*pud))
958                 return 0;
959
960         pmd = pmd_offset(pud, addr);
961         if (pmd_none(*pmd))
962                 return 0;
963
964         if (pmd_large(*pmd))
965                 return pfn_valid(pmd_pfn(*pmd));
966
967         pte = pte_offset_kernel(pmd, addr);
968         if (pte_none(*pte))
969                 return 0;
970
971         return pfn_valid(pte_pfn(*pte));
972 }
973
974 /*
975  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
976  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
977  * not need special handling anymore:
978  */
979 static struct vm_area_struct gate_vma = {
980         .vm_start       = VSYSCALL_START,
981         .vm_end         = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
982         .vm_page_prot   = PAGE_READONLY_EXEC,
983         .vm_flags       = VM_READ | VM_EXEC
984 };
985
986 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
987 {
988 #ifdef CONFIG_IA32_EMULATION
989         if (test_tsk_thread_flag(tsk, TIF_IA32))
990                 return NULL;
991 #endif
992         return &gate_vma;
993 }
994
995 int in_gate_area(struct task_struct *task, unsigned long addr)
996 {
997         struct vm_area_struct *vma = get_gate_vma(task);
998
999         if (!vma)
1000                 return 0;
1001
1002         return (addr >= vma->vm_start) && (addr < vma->vm_end);
1003 }
1004
1005 /*
1006  * Use this when you have no reliable task/vma, typically from interrupt
1007  * context. It is less reliable than using the task's vma and may give
1008  * false positives:
1009  */
1010 int in_gate_area_no_task(unsigned long addr)
1011 {
1012         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1013 }
1014
1015 const char *arch_vma_name(struct vm_area_struct *vma)
1016 {
1017         if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1018                 return "[vdso]";
1019         if (vma == &gate_vma)
1020                 return "[vsyscall]";
1021         return NULL;
1022 }
1023
1024 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1025 /*
1026  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1027  */
1028 static long __meminitdata addr_start, addr_end;
1029 static void __meminitdata *p_start, *p_end;
1030 static int __meminitdata node_start;
1031
1032 int __meminit
1033 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1034 {
1035         unsigned long addr = (unsigned long)start_page;
1036         unsigned long end = (unsigned long)(start_page + size);
1037         unsigned long next;
1038         pgd_t *pgd;
1039         pud_t *pud;
1040         pmd_t *pmd;
1041
1042         for (; addr < end; addr = next) {
1043                 void *p = NULL;
1044
1045                 pgd = vmemmap_pgd_populate(addr, node);
1046                 if (!pgd)
1047                         return -ENOMEM;
1048
1049                 pud = vmemmap_pud_populate(pgd, addr, node);
1050                 if (!pud)
1051                         return -ENOMEM;
1052
1053                 if (!cpu_has_pse) {
1054                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1055                         pmd = vmemmap_pmd_populate(pud, addr, node);
1056
1057                         if (!pmd)
1058                                 return -ENOMEM;
1059
1060                         p = vmemmap_pte_populate(pmd, addr, node);
1061
1062                         if (!p)
1063                                 return -ENOMEM;
1064
1065                         addr_end = addr + PAGE_SIZE;
1066                         p_end = p + PAGE_SIZE;
1067                 } else {
1068                         next = pmd_addr_end(addr, end);
1069
1070                         pmd = pmd_offset(pud, addr);
1071                         if (pmd_none(*pmd)) {
1072                                 pte_t entry;
1073
1074                                 p = vmemmap_alloc_block(PMD_SIZE, node);
1075                                 if (!p)
1076                                         return -ENOMEM;
1077
1078                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1079                                                 PAGE_KERNEL_LARGE);
1080                                 set_pmd(pmd, __pmd(pte_val(entry)));
1081
1082                                 /* check to see if we have contiguous blocks */
1083                                 if (p_end != p || node_start != node) {
1084                                         if (p_start)
1085                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1086                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1087                                         addr_start = addr;
1088                                         node_start = node;
1089                                         p_start = p;
1090                                 }
1091
1092                                 addr_end = addr + PMD_SIZE;
1093                                 p_end = p + PMD_SIZE;
1094                         } else
1095                                 vmemmap_verify((pte_t *)pmd, node, addr, next);
1096                 }
1097
1098         }
1099         return 0;
1100 }
1101
1102 void __meminit vmemmap_populate_print_last(void)
1103 {
1104         if (p_start) {
1105                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1106                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1107                 p_start = NULL;
1108                 p_end = NULL;
1109                 node_start = 0;
1110         }
1111 }
1112 #endif