Merge branch 'linux-linaro-lsk' into linux-linaro-lsk-android
[firefly-linux-kernel-4.4.55.git] / arch / x86 / mm / init_64.c
1 /*
2  *  linux/arch/x86_64/mm/init.c
3  *
4  *  Copyright (C) 1995  Linus Torvalds
5  *  Copyright (C) 2000  Pavel Machek <pavel@ucw.cz>
6  *  Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
7  */
8
9 #include <linux/signal.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/ptrace.h>
16 #include <linux/mman.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/smp.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/pagemap.h>
23 #include <linux/bootmem.h>
24 #include <linux/memblock.h>
25 #include <linux/proc_fs.h>
26 #include <linux/pci.h>
27 #include <linux/pfn.h>
28 #include <linux/poison.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/module.h>
31 #include <linux/memory.h>
32 #include <linux/memory_hotplug.h>
33 #include <linux/nmi.h>
34 #include <linux/gfp.h>
35 #include <linux/kcore.h>
36
37 #include <asm/processor.h>
38 #include <asm/bios_ebda.h>
39 #include <asm/uaccess.h>
40 #include <asm/pgtable.h>
41 #include <asm/pgalloc.h>
42 #include <asm/dma.h>
43 #include <asm/fixmap.h>
44 #include <asm/e820.h>
45 #include <asm/apic.h>
46 #include <asm/tlb.h>
47 #include <asm/mmu_context.h>
48 #include <asm/proto.h>
49 #include <asm/smp.h>
50 #include <asm/sections.h>
51 #include <asm/kdebug.h>
52 #include <asm/numa.h>
53 #include <asm/cacheflush.h>
54 #include <asm/init.h>
55 #include <asm/uv/uv.h>
56 #include <asm/setup.h>
57
58 #include "mm_internal.h"
59
60 static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
61                            unsigned long addr, unsigned long end)
62 {
63         addr &= PMD_MASK;
64         for (; addr < end; addr += PMD_SIZE) {
65                 pmd_t *pmd = pmd_page + pmd_index(addr);
66
67                 if (!pmd_present(*pmd))
68                         set_pmd(pmd, __pmd(addr | pmd_flag));
69         }
70 }
71 static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
72                           unsigned long addr, unsigned long end)
73 {
74         unsigned long next;
75
76         for (; addr < end; addr = next) {
77                 pud_t *pud = pud_page + pud_index(addr);
78                 pmd_t *pmd;
79
80                 next = (addr & PUD_MASK) + PUD_SIZE;
81                 if (next > end)
82                         next = end;
83
84                 if (pud_present(*pud)) {
85                         pmd = pmd_offset(pud, 0);
86                         ident_pmd_init(info->pmd_flag, pmd, addr, next);
87                         continue;
88                 }
89                 pmd = (pmd_t *)info->alloc_pgt_page(info->context);
90                 if (!pmd)
91                         return -ENOMEM;
92                 ident_pmd_init(info->pmd_flag, pmd, addr, next);
93                 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
94         }
95
96         return 0;
97 }
98
99 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
100                               unsigned long addr, unsigned long end)
101 {
102         unsigned long next;
103         int result;
104         int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
105
106         for (; addr < end; addr = next) {
107                 pgd_t *pgd = pgd_page + pgd_index(addr) + off;
108                 pud_t *pud;
109
110                 next = (addr & PGDIR_MASK) + PGDIR_SIZE;
111                 if (next > end)
112                         next = end;
113
114                 if (pgd_present(*pgd)) {
115                         pud = pud_offset(pgd, 0);
116                         result = ident_pud_init(info, pud, addr, next);
117                         if (result)
118                                 return result;
119                         continue;
120                 }
121
122                 pud = (pud_t *)info->alloc_pgt_page(info->context);
123                 if (!pud)
124                         return -ENOMEM;
125                 result = ident_pud_init(info, pud, addr, next);
126                 if (result)
127                         return result;
128                 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
129         }
130
131         return 0;
132 }
133
134 static int __init parse_direct_gbpages_off(char *arg)
135 {
136         direct_gbpages = 0;
137         return 0;
138 }
139 early_param("nogbpages", parse_direct_gbpages_off);
140
141 static int __init parse_direct_gbpages_on(char *arg)
142 {
143         direct_gbpages = 1;
144         return 0;
145 }
146 early_param("gbpages", parse_direct_gbpages_on);
147
148 /*
149  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
150  * physical space so we can cache the place of the first one and move
151  * around without checking the pgd every time.
152  */
153
154 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
155 EXPORT_SYMBOL_GPL(__supported_pte_mask);
156
157 int force_personality32;
158
159 /*
160  * noexec32=on|off
161  * Control non executable heap for 32bit processes.
162  * To control the stack too use noexec=off
163  *
164  * on   PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
165  * off  PROT_READ implies PROT_EXEC
166  */
167 static int __init nonx32_setup(char *str)
168 {
169         if (!strcmp(str, "on"))
170                 force_personality32 &= ~READ_IMPLIES_EXEC;
171         else if (!strcmp(str, "off"))
172                 force_personality32 |= READ_IMPLIES_EXEC;
173         return 1;
174 }
175 __setup("noexec32=", nonx32_setup);
176
177 /*
178  * When memory was added/removed make sure all the processes MM have
179  * suitable PGD entries in the local PGD level page.
180  */
181 void sync_global_pgds(unsigned long start, unsigned long end)
182 {
183         unsigned long address;
184
185         for (address = start; address <= end; address += PGDIR_SIZE) {
186                 const pgd_t *pgd_ref = pgd_offset_k(address);
187                 struct page *page;
188
189                 if (pgd_none(*pgd_ref))
190                         continue;
191
192                 spin_lock(&pgd_lock);
193                 list_for_each_entry(page, &pgd_list, lru) {
194                         pgd_t *pgd;
195                         spinlock_t *pgt_lock;
196
197                         pgd = (pgd_t *)page_address(page) + pgd_index(address);
198                         /* the pgt_lock only for Xen */
199                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
200                         spin_lock(pgt_lock);
201
202                         if (pgd_none(*pgd))
203                                 set_pgd(pgd, *pgd_ref);
204                         else
205                                 BUG_ON(pgd_page_vaddr(*pgd)
206                                        != pgd_page_vaddr(*pgd_ref));
207
208                         spin_unlock(pgt_lock);
209                 }
210                 spin_unlock(&pgd_lock);
211         }
212 }
213
214 /*
215  * NOTE: This function is marked __ref because it calls __init function
216  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
217  */
218 static __ref void *spp_getpage(void)
219 {
220         void *ptr;
221
222         if (after_bootmem)
223                 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
224         else
225                 ptr = alloc_bootmem_pages(PAGE_SIZE);
226
227         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
228                 panic("set_pte_phys: cannot allocate page data %s\n",
229                         after_bootmem ? "after bootmem" : "");
230         }
231
232         pr_debug("spp_getpage %p\n", ptr);
233
234         return ptr;
235 }
236
237 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
238 {
239         if (pgd_none(*pgd)) {
240                 pud_t *pud = (pud_t *)spp_getpage();
241                 pgd_populate(&init_mm, pgd, pud);
242                 if (pud != pud_offset(pgd, 0))
243                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
244                                pud, pud_offset(pgd, 0));
245         }
246         return pud_offset(pgd, vaddr);
247 }
248
249 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
250 {
251         if (pud_none(*pud)) {
252                 pmd_t *pmd = (pmd_t *) spp_getpage();
253                 pud_populate(&init_mm, pud, pmd);
254                 if (pmd != pmd_offset(pud, 0))
255                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
256                                pmd, pmd_offset(pud, 0));
257         }
258         return pmd_offset(pud, vaddr);
259 }
260
261 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
262 {
263         if (pmd_none(*pmd)) {
264                 pte_t *pte = (pte_t *) spp_getpage();
265                 pmd_populate_kernel(&init_mm, pmd, pte);
266                 if (pte != pte_offset_kernel(pmd, 0))
267                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
268         }
269         return pte_offset_kernel(pmd, vaddr);
270 }
271
272 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
273 {
274         pud_t *pud;
275         pmd_t *pmd;
276         pte_t *pte;
277
278         pud = pud_page + pud_index(vaddr);
279         pmd = fill_pmd(pud, vaddr);
280         pte = fill_pte(pmd, vaddr);
281
282         set_pte(pte, new_pte);
283
284         /*
285          * It's enough to flush this one mapping.
286          * (PGE mappings get flushed as well)
287          */
288         __flush_tlb_one(vaddr);
289 }
290
291 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
292 {
293         pgd_t *pgd;
294         pud_t *pud_page;
295
296         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
297
298         pgd = pgd_offset_k(vaddr);
299         if (pgd_none(*pgd)) {
300                 printk(KERN_ERR
301                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
302                 return;
303         }
304         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
305         set_pte_vaddr_pud(pud_page, vaddr, pteval);
306 }
307
308 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
309 {
310         pgd_t *pgd;
311         pud_t *pud;
312
313         pgd = pgd_offset_k(vaddr);
314         pud = fill_pud(pgd, vaddr);
315         return fill_pmd(pud, vaddr);
316 }
317
318 pte_t * __init populate_extra_pte(unsigned long vaddr)
319 {
320         pmd_t *pmd;
321
322         pmd = populate_extra_pmd(vaddr);
323         return fill_pte(pmd, vaddr);
324 }
325
326 /*
327  * Create large page table mappings for a range of physical addresses.
328  */
329 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
330                                                 pgprot_t prot)
331 {
332         pgd_t *pgd;
333         pud_t *pud;
334         pmd_t *pmd;
335
336         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
337         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
338                 pgd = pgd_offset_k((unsigned long)__va(phys));
339                 if (pgd_none(*pgd)) {
340                         pud = (pud_t *) spp_getpage();
341                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
342                                                 _PAGE_USER));
343                 }
344                 pud = pud_offset(pgd, (unsigned long)__va(phys));
345                 if (pud_none(*pud)) {
346                         pmd = (pmd_t *) spp_getpage();
347                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
348                                                 _PAGE_USER));
349                 }
350                 pmd = pmd_offset(pud, phys);
351                 BUG_ON(!pmd_none(*pmd));
352                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
353         }
354 }
355
356 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
357 {
358         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
359 }
360
361 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
362 {
363         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
364 }
365
366 /*
367  * The head.S code sets up the kernel high mapping:
368  *
369  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
370  *
371  * phys_addr holds the negative offset to the kernel, which is added
372  * to the compile time generated pmds. This results in invalid pmds up
373  * to the point where we hit the physaddr 0 mapping.
374  *
375  * We limit the mappings to the region from _text to _brk_end.  _brk_end
376  * is rounded up to the 2MB boundary. This catches the invalid pmds as
377  * well, as they are located before _text:
378  */
379 void __init cleanup_highmap(void)
380 {
381         unsigned long vaddr = __START_KERNEL_map;
382         unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
383         unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
384         pmd_t *pmd = level2_kernel_pgt;
385
386         /*
387          * Native path, max_pfn_mapped is not set yet.
388          * Xen has valid max_pfn_mapped set in
389          *      arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
390          */
391         if (max_pfn_mapped)
392                 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
393
394         for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
395                 if (pmd_none(*pmd))
396                         continue;
397                 if (vaddr < (unsigned long) _text || vaddr > end)
398                         set_pmd(pmd, __pmd(0));
399         }
400 }
401
402 static unsigned long __meminit
403 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
404               pgprot_t prot)
405 {
406         unsigned long pages = 0, next;
407         unsigned long last_map_addr = end;
408         int i;
409
410         pte_t *pte = pte_page + pte_index(addr);
411
412         for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {
413                 next = (addr & PAGE_MASK) + PAGE_SIZE;
414                 if (addr >= end) {
415                         if (!after_bootmem &&
416                             !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&
417                             !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))
418                                 set_pte(pte, __pte(0));
419                         continue;
420                 }
421
422                 /*
423                  * We will re-use the existing mapping.
424                  * Xen for example has some special requirements, like mapping
425                  * pagetable pages as RO. So assume someone who pre-setup
426                  * these mappings are more intelligent.
427                  */
428                 if (pte_val(*pte)) {
429                         if (!after_bootmem)
430                                 pages++;
431                         continue;
432                 }
433
434                 if (0)
435                         printk("   pte=%p addr=%lx pte=%016lx\n",
436                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
437                 pages++;
438                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
439                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
440         }
441
442         update_page_count(PG_LEVEL_4K, pages);
443
444         return last_map_addr;
445 }
446
447 static unsigned long __meminit
448 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
449               unsigned long page_size_mask, pgprot_t prot)
450 {
451         unsigned long pages = 0, next;
452         unsigned long last_map_addr = end;
453
454         int i = pmd_index(address);
455
456         for (; i < PTRS_PER_PMD; i++, address = next) {
457                 pmd_t *pmd = pmd_page + pmd_index(address);
458                 pte_t *pte;
459                 pgprot_t new_prot = prot;
460
461                 next = (address & PMD_MASK) + PMD_SIZE;
462                 if (address >= end) {
463                         if (!after_bootmem &&
464                             !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&
465                             !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))
466                                 set_pmd(pmd, __pmd(0));
467                         continue;
468                 }
469
470                 if (pmd_val(*pmd)) {
471                         if (!pmd_large(*pmd)) {
472                                 spin_lock(&init_mm.page_table_lock);
473                                 pte = (pte_t *)pmd_page_vaddr(*pmd);
474                                 last_map_addr = phys_pte_init(pte, address,
475                                                                 end, prot);
476                                 spin_unlock(&init_mm.page_table_lock);
477                                 continue;
478                         }
479                         /*
480                          * If we are ok with PG_LEVEL_2M mapping, then we will
481                          * use the existing mapping,
482                          *
483                          * Otherwise, we will split the large page mapping but
484                          * use the same existing protection bits except for
485                          * large page, so that we don't violate Intel's TLB
486                          * Application note (317080) which says, while changing
487                          * the page sizes, new and old translations should
488                          * not differ with respect to page frame and
489                          * attributes.
490                          */
491                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
492                                 if (!after_bootmem)
493                                         pages++;
494                                 last_map_addr = next;
495                                 continue;
496                         }
497                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
498                 }
499
500                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
501                         pages++;
502                         spin_lock(&init_mm.page_table_lock);
503                         set_pte((pte_t *)pmd,
504                                 pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,
505                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
506                         spin_unlock(&init_mm.page_table_lock);
507                         last_map_addr = next;
508                         continue;
509                 }
510
511                 pte = alloc_low_page();
512                 last_map_addr = phys_pte_init(pte, address, end, new_prot);
513
514                 spin_lock(&init_mm.page_table_lock);
515                 pmd_populate_kernel(&init_mm, pmd, pte);
516                 spin_unlock(&init_mm.page_table_lock);
517         }
518         update_page_count(PG_LEVEL_2M, pages);
519         return last_map_addr;
520 }
521
522 static unsigned long __meminit
523 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
524                          unsigned long page_size_mask)
525 {
526         unsigned long pages = 0, next;
527         unsigned long last_map_addr = end;
528         int i = pud_index(addr);
529
530         for (; i < PTRS_PER_PUD; i++, addr = next) {
531                 pud_t *pud = pud_page + pud_index(addr);
532                 pmd_t *pmd;
533                 pgprot_t prot = PAGE_KERNEL;
534
535                 next = (addr & PUD_MASK) + PUD_SIZE;
536                 if (addr >= end) {
537                         if (!after_bootmem &&
538                             !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&
539                             !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))
540                                 set_pud(pud, __pud(0));
541                         continue;
542                 }
543
544                 if (pud_val(*pud)) {
545                         if (!pud_large(*pud)) {
546                                 pmd = pmd_offset(pud, 0);
547                                 last_map_addr = phys_pmd_init(pmd, addr, end,
548                                                          page_size_mask, prot);
549                                 __flush_tlb_all();
550                                 continue;
551                         }
552                         /*
553                          * If we are ok with PG_LEVEL_1G mapping, then we will
554                          * use the existing mapping.
555                          *
556                          * Otherwise, we will split the gbpage mapping but use
557                          * the same existing protection  bits except for large
558                          * page, so that we don't violate Intel's TLB
559                          * Application note (317080) which says, while changing
560                          * the page sizes, new and old translations should
561                          * not differ with respect to page frame and
562                          * attributes.
563                          */
564                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
565                                 if (!after_bootmem)
566                                         pages++;
567                                 last_map_addr = next;
568                                 continue;
569                         }
570                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
571                 }
572
573                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
574                         pages++;
575                         spin_lock(&init_mm.page_table_lock);
576                         set_pte((pte_t *)pud,
577                                 pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,
578                                         PAGE_KERNEL_LARGE));
579                         spin_unlock(&init_mm.page_table_lock);
580                         last_map_addr = next;
581                         continue;
582                 }
583
584                 pmd = alloc_low_page();
585                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
586                                               prot);
587
588                 spin_lock(&init_mm.page_table_lock);
589                 pud_populate(&init_mm, pud, pmd);
590                 spin_unlock(&init_mm.page_table_lock);
591         }
592         __flush_tlb_all();
593
594         update_page_count(PG_LEVEL_1G, pages);
595
596         return last_map_addr;
597 }
598
599 unsigned long __meminit
600 kernel_physical_mapping_init(unsigned long start,
601                              unsigned long end,
602                              unsigned long page_size_mask)
603 {
604         bool pgd_changed = false;
605         unsigned long next, last_map_addr = end;
606         unsigned long addr;
607
608         start = (unsigned long)__va(start);
609         end = (unsigned long)__va(end);
610         addr = start;
611
612         for (; start < end; start = next) {
613                 pgd_t *pgd = pgd_offset_k(start);
614                 pud_t *pud;
615
616                 next = (start & PGDIR_MASK) + PGDIR_SIZE;
617
618                 if (pgd_val(*pgd)) {
619                         pud = (pud_t *)pgd_page_vaddr(*pgd);
620                         last_map_addr = phys_pud_init(pud, __pa(start),
621                                                  __pa(end), page_size_mask);
622                         continue;
623                 }
624
625                 pud = alloc_low_page();
626                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),
627                                                  page_size_mask);
628
629                 spin_lock(&init_mm.page_table_lock);
630                 pgd_populate(&init_mm, pgd, pud);
631                 spin_unlock(&init_mm.page_table_lock);
632                 pgd_changed = true;
633         }
634
635         if (pgd_changed)
636                 sync_global_pgds(addr, end - 1);
637
638         __flush_tlb_all();
639
640         return last_map_addr;
641 }
642
643 #ifndef CONFIG_NUMA
644 void __init initmem_init(void)
645 {
646         memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
647 }
648 #endif
649
650 void __init paging_init(void)
651 {
652         sparse_memory_present_with_active_regions(MAX_NUMNODES);
653         sparse_init();
654
655         /*
656          * clear the default setting with node 0
657          * note: don't use nodes_clear here, that is really clearing when
658          *       numa support is not compiled in, and later node_set_state
659          *       will not set it back.
660          */
661         node_clear_state(0, N_MEMORY);
662         if (N_MEMORY != N_NORMAL_MEMORY)
663                 node_clear_state(0, N_NORMAL_MEMORY);
664
665         zone_sizes_init();
666 }
667
668 /*
669  * Memory hotplug specific functions
670  */
671 #ifdef CONFIG_MEMORY_HOTPLUG
672 /*
673  * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
674  * updating.
675  */
676 static void  update_end_of_memory_vars(u64 start, u64 size)
677 {
678         unsigned long end_pfn = PFN_UP(start + size);
679
680         if (end_pfn > max_pfn) {
681                 max_pfn = end_pfn;
682                 max_low_pfn = end_pfn;
683                 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
684         }
685 }
686
687 /*
688  * Memory is added always to NORMAL zone. This means you will never get
689  * additional DMA/DMA32 memory.
690  */
691 int arch_add_memory(int nid, u64 start, u64 size)
692 {
693         struct pglist_data *pgdat = NODE_DATA(nid);
694         struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
695         unsigned long start_pfn = start >> PAGE_SHIFT;
696         unsigned long nr_pages = size >> PAGE_SHIFT;
697         int ret;
698
699         init_memory_mapping(start, start + size);
700
701         ret = __add_pages(nid, zone, start_pfn, nr_pages);
702         WARN_ON_ONCE(ret);
703
704         /* update max_pfn, max_low_pfn and high_memory */
705         update_end_of_memory_vars(start, size);
706
707         return ret;
708 }
709 EXPORT_SYMBOL_GPL(arch_add_memory);
710
711 #define PAGE_INUSE 0xFD
712
713 static void __meminit free_pagetable(struct page *page, int order)
714 {
715         struct zone *zone;
716         bool bootmem = false;
717         unsigned long magic;
718         unsigned int nr_pages = 1 << order;
719
720         /* bootmem page has reserved flag */
721         if (PageReserved(page)) {
722                 __ClearPageReserved(page);
723                 bootmem = true;
724
725                 magic = (unsigned long)page->lru.next;
726                 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
727                         while (nr_pages--)
728                                 put_page_bootmem(page++);
729                 } else
730                         __free_pages_bootmem(page, order);
731         } else
732                 free_pages((unsigned long)page_address(page), order);
733
734         /*
735          * SECTION_INFO pages and MIX_SECTION_INFO pages
736          * are all allocated by bootmem.
737          */
738         if (bootmem) {
739                 zone = page_zone(page);
740                 zone_span_writelock(zone);
741                 zone->present_pages += nr_pages;
742                 zone_span_writeunlock(zone);
743                 totalram_pages += nr_pages;
744         }
745 }
746
747 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
748 {
749         pte_t *pte;
750         int i;
751
752         for (i = 0; i < PTRS_PER_PTE; i++) {
753                 pte = pte_start + i;
754                 if (pte_val(*pte))
755                         return;
756         }
757
758         /* free a pte talbe */
759         free_pagetable(pmd_page(*pmd), 0);
760         spin_lock(&init_mm.page_table_lock);
761         pmd_clear(pmd);
762         spin_unlock(&init_mm.page_table_lock);
763 }
764
765 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
766 {
767         pmd_t *pmd;
768         int i;
769
770         for (i = 0; i < PTRS_PER_PMD; i++) {
771                 pmd = pmd_start + i;
772                 if (pmd_val(*pmd))
773                         return;
774         }
775
776         /* free a pmd talbe */
777         free_pagetable(pud_page(*pud), 0);
778         spin_lock(&init_mm.page_table_lock);
779         pud_clear(pud);
780         spin_unlock(&init_mm.page_table_lock);
781 }
782
783 /* Return true if pgd is changed, otherwise return false. */
784 static bool __meminit free_pud_table(pud_t *pud_start, pgd_t *pgd)
785 {
786         pud_t *pud;
787         int i;
788
789         for (i = 0; i < PTRS_PER_PUD; i++) {
790                 pud = pud_start + i;
791                 if (pud_val(*pud))
792                         return false;
793         }
794
795         /* free a pud table */
796         free_pagetable(pgd_page(*pgd), 0);
797         spin_lock(&init_mm.page_table_lock);
798         pgd_clear(pgd);
799         spin_unlock(&init_mm.page_table_lock);
800
801         return true;
802 }
803
804 static void __meminit
805 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
806                  bool direct)
807 {
808         unsigned long next, pages = 0;
809         pte_t *pte;
810         void *page_addr;
811         phys_addr_t phys_addr;
812
813         pte = pte_start + pte_index(addr);
814         for (; addr < end; addr = next, pte++) {
815                 next = (addr + PAGE_SIZE) & PAGE_MASK;
816                 if (next > end)
817                         next = end;
818
819                 if (!pte_present(*pte))
820                         continue;
821
822                 /*
823                  * We mapped [0,1G) memory as identity mapping when
824                  * initializing, in arch/x86/kernel/head_64.S. These
825                  * pagetables cannot be removed.
826                  */
827                 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
828                 if (phys_addr < (phys_addr_t)0x40000000)
829                         return;
830
831                 if (IS_ALIGNED(addr, PAGE_SIZE) &&
832                     IS_ALIGNED(next, PAGE_SIZE)) {
833                         /*
834                          * Do not free direct mapping pages since they were
835                          * freed when offlining, or simplely not in use.
836                          */
837                         if (!direct)
838                                 free_pagetable(pte_page(*pte), 0);
839
840                         spin_lock(&init_mm.page_table_lock);
841                         pte_clear(&init_mm, addr, pte);
842                         spin_unlock(&init_mm.page_table_lock);
843
844                         /* For non-direct mapping, pages means nothing. */
845                         pages++;
846                 } else {
847                         /*
848                          * If we are here, we are freeing vmemmap pages since
849                          * direct mapped memory ranges to be freed are aligned.
850                          *
851                          * If we are not removing the whole page, it means
852                          * other page structs in this page are being used and
853                          * we canot remove them. So fill the unused page_structs
854                          * with 0xFD, and remove the page when it is wholly
855                          * filled with 0xFD.
856                          */
857                         memset((void *)addr, PAGE_INUSE, next - addr);
858
859                         page_addr = page_address(pte_page(*pte));
860                         if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
861                                 free_pagetable(pte_page(*pte), 0);
862
863                                 spin_lock(&init_mm.page_table_lock);
864                                 pte_clear(&init_mm, addr, pte);
865                                 spin_unlock(&init_mm.page_table_lock);
866                         }
867                 }
868         }
869
870         /* Call free_pte_table() in remove_pmd_table(). */
871         flush_tlb_all();
872         if (direct)
873                 update_page_count(PG_LEVEL_4K, -pages);
874 }
875
876 static void __meminit
877 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
878                  bool direct)
879 {
880         unsigned long next, pages = 0;
881         pte_t *pte_base;
882         pmd_t *pmd;
883         void *page_addr;
884
885         pmd = pmd_start + pmd_index(addr);
886         for (; addr < end; addr = next, pmd++) {
887                 next = pmd_addr_end(addr, end);
888
889                 if (!pmd_present(*pmd))
890                         continue;
891
892                 if (pmd_large(*pmd)) {
893                         if (IS_ALIGNED(addr, PMD_SIZE) &&
894                             IS_ALIGNED(next, PMD_SIZE)) {
895                                 if (!direct)
896                                         free_pagetable(pmd_page(*pmd),
897                                                        get_order(PMD_SIZE));
898
899                                 spin_lock(&init_mm.page_table_lock);
900                                 pmd_clear(pmd);
901                                 spin_unlock(&init_mm.page_table_lock);
902                                 pages++;
903                         } else {
904                                 /* If here, we are freeing vmemmap pages. */
905                                 memset((void *)addr, PAGE_INUSE, next - addr);
906
907                                 page_addr = page_address(pmd_page(*pmd));
908                                 if (!memchr_inv(page_addr, PAGE_INUSE,
909                                                 PMD_SIZE)) {
910                                         free_pagetable(pmd_page(*pmd),
911                                                        get_order(PMD_SIZE));
912
913                                         spin_lock(&init_mm.page_table_lock);
914                                         pmd_clear(pmd);
915                                         spin_unlock(&init_mm.page_table_lock);
916                                 }
917                         }
918
919                         continue;
920                 }
921
922                 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
923                 remove_pte_table(pte_base, addr, next, direct);
924                 free_pte_table(pte_base, pmd);
925         }
926
927         /* Call free_pmd_table() in remove_pud_table(). */
928         if (direct)
929                 update_page_count(PG_LEVEL_2M, -pages);
930 }
931
932 static void __meminit
933 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
934                  bool direct)
935 {
936         unsigned long next, pages = 0;
937         pmd_t *pmd_base;
938         pud_t *pud;
939         void *page_addr;
940
941         pud = pud_start + pud_index(addr);
942         for (; addr < end; addr = next, pud++) {
943                 next = pud_addr_end(addr, end);
944
945                 if (!pud_present(*pud))
946                         continue;
947
948                 if (pud_large(*pud)) {
949                         if (IS_ALIGNED(addr, PUD_SIZE) &&
950                             IS_ALIGNED(next, PUD_SIZE)) {
951                                 if (!direct)
952                                         free_pagetable(pud_page(*pud),
953                                                        get_order(PUD_SIZE));
954
955                                 spin_lock(&init_mm.page_table_lock);
956                                 pud_clear(pud);
957                                 spin_unlock(&init_mm.page_table_lock);
958                                 pages++;
959                         } else {
960                                 /* If here, we are freeing vmemmap pages. */
961                                 memset((void *)addr, PAGE_INUSE, next - addr);
962
963                                 page_addr = page_address(pud_page(*pud));
964                                 if (!memchr_inv(page_addr, PAGE_INUSE,
965                                                 PUD_SIZE)) {
966                                         free_pagetable(pud_page(*pud),
967                                                        get_order(PUD_SIZE));
968
969                                         spin_lock(&init_mm.page_table_lock);
970                                         pud_clear(pud);
971                                         spin_unlock(&init_mm.page_table_lock);
972                                 }
973                         }
974
975                         continue;
976                 }
977
978                 pmd_base = (pmd_t *)pud_page_vaddr(*pud);
979                 remove_pmd_table(pmd_base, addr, next, direct);
980                 free_pmd_table(pmd_base, pud);
981         }
982
983         if (direct)
984                 update_page_count(PG_LEVEL_1G, -pages);
985 }
986
987 /* start and end are both virtual address. */
988 static void __meminit
989 remove_pagetable(unsigned long start, unsigned long end, bool direct)
990 {
991         unsigned long next;
992         pgd_t *pgd;
993         pud_t *pud;
994         bool pgd_changed = false;
995
996         for (; start < end; start = next) {
997                 next = pgd_addr_end(start, end);
998
999                 pgd = pgd_offset_k(start);
1000                 if (!pgd_present(*pgd))
1001                         continue;
1002
1003                 pud = (pud_t *)pgd_page_vaddr(*pgd);
1004                 remove_pud_table(pud, start, next, direct);
1005                 if (free_pud_table(pud, pgd))
1006                         pgd_changed = true;
1007         }
1008
1009         if (pgd_changed)
1010                 sync_global_pgds(start, end - 1);
1011
1012         flush_tlb_all();
1013 }
1014
1015 void __ref vmemmap_free(unsigned long start, unsigned long end)
1016 {
1017         remove_pagetable(start, end, false);
1018 }
1019
1020 #ifdef CONFIG_MEMORY_HOTREMOVE
1021 static void __meminit
1022 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1023 {
1024         start = (unsigned long)__va(start);
1025         end = (unsigned long)__va(end);
1026
1027         remove_pagetable(start, end, true);
1028 }
1029
1030 int __ref arch_remove_memory(u64 start, u64 size)
1031 {
1032         unsigned long start_pfn = start >> PAGE_SHIFT;
1033         unsigned long nr_pages = size >> PAGE_SHIFT;
1034         struct zone *zone;
1035         int ret;
1036
1037         zone = page_zone(pfn_to_page(start_pfn));
1038         kernel_physical_mapping_remove(start, start + size);
1039         ret = __remove_pages(zone, start_pfn, nr_pages);
1040         WARN_ON_ONCE(ret);
1041
1042         return ret;
1043 }
1044 #endif
1045 #endif /* CONFIG_MEMORY_HOTPLUG */
1046
1047 static struct kcore_list kcore_vsyscall;
1048
1049 static void __init register_page_bootmem_info(void)
1050 {
1051 #ifdef CONFIG_NUMA
1052         int i;
1053
1054         for_each_online_node(i)
1055                 register_page_bootmem_info_node(NODE_DATA(i));
1056 #endif
1057 }
1058
1059 void __init mem_init(void)
1060 {
1061         long codesize, reservedpages, datasize, initsize;
1062         unsigned long absent_pages;
1063
1064         pci_iommu_alloc();
1065
1066         /* clear_bss() already clear the empty_zero_page */
1067
1068         register_page_bootmem_info();
1069
1070         /* this will put all memory onto the freelists */
1071         totalram_pages = free_all_bootmem();
1072
1073         absent_pages = absent_pages_in_range(0, max_pfn);
1074         reservedpages = max_pfn - totalram_pages - absent_pages;
1075         after_bootmem = 1;
1076
1077         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
1078         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
1079         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
1080
1081         /* Register memory areas for /proc/kcore */
1082         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
1083                          VSYSCALL_END - VSYSCALL_START, KCORE_OTHER);
1084
1085         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
1086                          "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
1087                 nr_free_pages() << (PAGE_SHIFT-10),
1088                 max_pfn << (PAGE_SHIFT-10),
1089                 codesize >> 10,
1090                 absent_pages << (PAGE_SHIFT-10),
1091                 reservedpages << (PAGE_SHIFT-10),
1092                 datasize >> 10,
1093                 initsize >> 10);
1094 }
1095
1096 #ifdef CONFIG_DEBUG_RODATA
1097 const int rodata_test_data = 0xC3;
1098 EXPORT_SYMBOL_GPL(rodata_test_data);
1099
1100 int kernel_set_to_readonly;
1101
1102 void set_kernel_text_rw(void)
1103 {
1104         unsigned long start = PFN_ALIGN(_text);
1105         unsigned long end = PFN_ALIGN(__stop___ex_table);
1106
1107         if (!kernel_set_to_readonly)
1108                 return;
1109
1110         pr_debug("Set kernel text: %lx - %lx for read write\n",
1111                  start, end);
1112
1113         /*
1114          * Make the kernel identity mapping for text RW. Kernel text
1115          * mapping will always be RO. Refer to the comment in
1116          * static_protections() in pageattr.c
1117          */
1118         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1119 }
1120
1121 void set_kernel_text_ro(void)
1122 {
1123         unsigned long start = PFN_ALIGN(_text);
1124         unsigned long end = PFN_ALIGN(__stop___ex_table);
1125
1126         if (!kernel_set_to_readonly)
1127                 return;
1128
1129         pr_debug("Set kernel text: %lx - %lx for read only\n",
1130                  start, end);
1131
1132         /*
1133          * Set the kernel identity mapping for text RO.
1134          */
1135         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1136 }
1137
1138 void mark_rodata_ro(void)
1139 {
1140         unsigned long start = PFN_ALIGN(_text);
1141         unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1142         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1143         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1144         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1145         unsigned long all_end;
1146
1147         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1148                (end - start) >> 10);
1149         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1150
1151         kernel_set_to_readonly = 1;
1152
1153         /*
1154          * The rodata/data/bss/brk section (but not the kernel text!)
1155          * should also be not-executable.
1156          *
1157          * We align all_end to PMD_SIZE because the existing mapping
1158          * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1159          * split the PMD and the reminder between _brk_end and the end
1160          * of the PMD will remain mapped executable.
1161          *
1162          * Any PMD which was setup after the one which covers _brk_end
1163          * has been zapped already via cleanup_highmem().
1164          */
1165         all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1166         set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
1167
1168         rodata_test();
1169
1170 #ifdef CONFIG_CPA_DEBUG
1171         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1172         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1173
1174         printk(KERN_INFO "Testing CPA: again\n");
1175         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1176 #endif
1177
1178         free_init_pages("unused kernel memory",
1179                         (unsigned long) __va(__pa_symbol(text_end)),
1180                         (unsigned long) __va(__pa_symbol(rodata_start)));
1181
1182         free_init_pages("unused kernel memory",
1183                         (unsigned long) __va(__pa_symbol(rodata_end)),
1184                         (unsigned long) __va(__pa_symbol(_sdata)));
1185 }
1186
1187 #endif
1188
1189 int kern_addr_valid(unsigned long addr)
1190 {
1191         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1192         pgd_t *pgd;
1193         pud_t *pud;
1194         pmd_t *pmd;
1195         pte_t *pte;
1196
1197         if (above != 0 && above != -1UL)
1198                 return 0;
1199
1200         pgd = pgd_offset_k(addr);
1201         if (pgd_none(*pgd))
1202                 return 0;
1203
1204         pud = pud_offset(pgd, addr);
1205         if (pud_none(*pud))
1206                 return 0;
1207
1208         if (pud_large(*pud))
1209                 return pfn_valid(pud_pfn(*pud));
1210
1211         pmd = pmd_offset(pud, addr);
1212         if (pmd_none(*pmd))
1213                 return 0;
1214
1215         if (pmd_large(*pmd))
1216                 return pfn_valid(pmd_pfn(*pmd));
1217
1218         pte = pte_offset_kernel(pmd, addr);
1219         if (pte_none(*pte))
1220                 return 0;
1221
1222         return pfn_valid(pte_pfn(*pte));
1223 }
1224
1225 /*
1226  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
1227  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1228  * not need special handling anymore:
1229  */
1230 static struct vm_area_struct gate_vma = {
1231         .vm_start       = VSYSCALL_START,
1232         .vm_end         = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1233         .vm_page_prot   = PAGE_READONLY_EXEC,
1234         .vm_flags       = VM_READ | VM_EXEC
1235 };
1236
1237 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
1238 {
1239 #ifdef CONFIG_IA32_EMULATION
1240         if (!mm || mm->context.ia32_compat)
1241                 return NULL;
1242 #endif
1243         return &gate_vma;
1244 }
1245
1246 int in_gate_area(struct mm_struct *mm, unsigned long addr)
1247 {
1248         struct vm_area_struct *vma = get_gate_vma(mm);
1249
1250         if (!vma)
1251                 return 0;
1252
1253         return (addr >= vma->vm_start) && (addr < vma->vm_end);
1254 }
1255
1256 /*
1257  * Use this when you have no reliable mm, typically from interrupt
1258  * context. It is less reliable than using a task's mm and may give
1259  * false positives.
1260  */
1261 int in_gate_area_no_mm(unsigned long addr)
1262 {
1263         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1264 }
1265
1266 const char *arch_vma_name(struct vm_area_struct *vma)
1267 {
1268         if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1269                 return "[vdso]";
1270         if (vma == &gate_vma)
1271                 return "[vsyscall]";
1272         return NULL;
1273 }
1274
1275 #ifdef CONFIG_X86_UV
1276 unsigned long memory_block_size_bytes(void)
1277 {
1278         if (is_uv_system()) {
1279                 printk(KERN_INFO "UV: memory block size 2GB\n");
1280                 return 2UL * 1024 * 1024 * 1024;
1281         }
1282         return MIN_MEMORY_BLOCK_SIZE;
1283 }
1284 #endif
1285
1286 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1287 /*
1288  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1289  */
1290 static long __meminitdata addr_start, addr_end;
1291 static void __meminitdata *p_start, *p_end;
1292 static int __meminitdata node_start;
1293
1294 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1295                                                 unsigned long end, int node)
1296 {
1297         unsigned long addr;
1298         unsigned long next;
1299         pgd_t *pgd;
1300         pud_t *pud;
1301         pmd_t *pmd;
1302
1303         for (addr = start; addr < end; addr = next) {
1304                 next = pmd_addr_end(addr, end);
1305
1306                 pgd = vmemmap_pgd_populate(addr, node);
1307                 if (!pgd)
1308                         return -ENOMEM;
1309
1310                 pud = vmemmap_pud_populate(pgd, addr, node);
1311                 if (!pud)
1312                         return -ENOMEM;
1313
1314                 pmd = pmd_offset(pud, addr);
1315                 if (pmd_none(*pmd)) {
1316                         void *p;
1317
1318                         p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1319                         if (p) {
1320                                 pte_t entry;
1321
1322                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1323                                                 PAGE_KERNEL_LARGE);
1324                                 set_pmd(pmd, __pmd(pte_val(entry)));
1325
1326                                 /* check to see if we have contiguous blocks */
1327                                 if (p_end != p || node_start != node) {
1328                                         if (p_start)
1329                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1330                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1331                                         addr_start = addr;
1332                                         node_start = node;
1333                                         p_start = p;
1334                                 }
1335
1336                                 addr_end = addr + PMD_SIZE;
1337                                 p_end = p + PMD_SIZE;
1338                                 continue;
1339                         }
1340                 } else if (pmd_large(*pmd)) {
1341                         vmemmap_verify((pte_t *)pmd, node, addr, next);
1342                         continue;
1343                 }
1344                 pr_warn_once("vmemmap: falling back to regular page backing\n");
1345                 if (vmemmap_populate_basepages(addr, next, node))
1346                         return -ENOMEM;
1347         }
1348         return 0;
1349 }
1350
1351 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1352 {
1353         int err;
1354
1355         if (cpu_has_pse)
1356                 err = vmemmap_populate_hugepages(start, end, node);
1357         else
1358                 err = vmemmap_populate_basepages(start, end, node);
1359         if (!err)
1360                 sync_global_pgds(start, end - 1);
1361         return err;
1362 }
1363
1364 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1365 void register_page_bootmem_memmap(unsigned long section_nr,
1366                                   struct page *start_page, unsigned long size)
1367 {
1368         unsigned long addr = (unsigned long)start_page;
1369         unsigned long end = (unsigned long)(start_page + size);
1370         unsigned long next;
1371         pgd_t *pgd;
1372         pud_t *pud;
1373         pmd_t *pmd;
1374         unsigned int nr_pages;
1375         struct page *page;
1376
1377         for (; addr < end; addr = next) {
1378                 pte_t *pte = NULL;
1379
1380                 pgd = pgd_offset_k(addr);
1381                 if (pgd_none(*pgd)) {
1382                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1383                         continue;
1384                 }
1385                 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1386
1387                 pud = pud_offset(pgd, addr);
1388                 if (pud_none(*pud)) {
1389                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1390                         continue;
1391                 }
1392                 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1393
1394                 if (!cpu_has_pse) {
1395                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1396                         pmd = pmd_offset(pud, addr);
1397                         if (pmd_none(*pmd))
1398                                 continue;
1399                         get_page_bootmem(section_nr, pmd_page(*pmd),
1400                                          MIX_SECTION_INFO);
1401
1402                         pte = pte_offset_kernel(pmd, addr);
1403                         if (pte_none(*pte))
1404                                 continue;
1405                         get_page_bootmem(section_nr, pte_page(*pte),
1406                                          SECTION_INFO);
1407                 } else {
1408                         next = pmd_addr_end(addr, end);
1409
1410                         pmd = pmd_offset(pud, addr);
1411                         if (pmd_none(*pmd))
1412                                 continue;
1413
1414                         nr_pages = 1 << (get_order(PMD_SIZE));
1415                         page = pmd_page(*pmd);
1416                         while (nr_pages--)
1417                                 get_page_bootmem(section_nr, page++,
1418                                                  SECTION_INFO);
1419                 }
1420         }
1421 }
1422 #endif
1423
1424 void __meminit vmemmap_populate_print_last(void)
1425 {
1426         if (p_start) {
1427                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1428                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1429                 p_start = NULL;
1430                 p_end = NULL;
1431                 node_start = 0;
1432         }
1433 }
1434 #endif