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/setup.h>
  56
  57 #include "mm_internal.h"
  58
  59 static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
  60                            unsigned long addr, unsigned long end)
  61 {
  62         addr &= PMD_MASK;
  63         for (; addr < end; addr += PMD_SIZE) {
  64                 pmd_t *pmd = pmd_page + pmd_index(addr);
  65
  66                 if (!pmd_present(*pmd))
  67                         set_pmd(pmd, __pmd(addr | pmd_flag));
  68         }
  69 }
  70 static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
  71                           unsigned long addr, unsigned long end)
  72 {
  73         unsigned long next;
  74
  75         for (; addr < end; addr = next) {
  76                 pud_t *pud = pud_page + pud_index(addr);
  77                 pmd_t *pmd;
  78
  79                 next = (addr & PUD_MASK) + PUD_SIZE;
  80                 if (next > end)
  81                         next = end;
  82
  83                 if (pud_present(*pud)) {
  84                         pmd = pmd_offset(pud, 0);
  85                         ident_pmd_init(info->pmd_flag, pmd, addr, next);
  86                         continue;
  87                 }
  88                 pmd = (pmd_t *)info->alloc_pgt_page(info->context);
  89                 if (!pmd)
  90                         return -ENOMEM;
  91                 ident_pmd_init(info->pmd_flag, pmd, addr, next);
  92                 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
  93         }
  94
  95         return 0;
  96 }
  97
  98 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
  99                               unsigned long addr, unsigned long end)
 100 {
 101         unsigned long next;
 102         int result;
 103         int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
 104
 105         for (; addr < end; addr = next) {
 106                 pgd_t *pgd = pgd_page + pgd_index(addr) + off;
 107                 pud_t *pud;
 108
 109                 next = (addr & PGDIR_MASK) + PGDIR_SIZE;
 110                 if (next > end)
 111                         next = end;
 112
 113                 if (pgd_present(*pgd)) {
 114                         pud = pud_offset(pgd, 0);
 115                         result = ident_pud_init(info, pud, addr, next);
 116                         if (result)
 117                                 return result;
 118                         continue;
 119                 }
 120
 121                 pud = (pud_t *)info->alloc_pgt_page(info->context);
 122                 if (!pud)
 123                         return -ENOMEM;
 124                 result = ident_pud_init(info, pud, addr, next);
 125                 if (result)
 126                         return result;
 127                 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
 128         }
 129
 130         return 0;
 131 }
 132
 133 static int __init parse_direct_gbpages_off(char *arg)
 134 {
 135         direct_gbpages = 0;
 136         return 0;
 137 }
 138 early_param("nogbpages", parse_direct_gbpages_off);
 139
 140 static int __init parse_direct_gbpages_on(char *arg)
 141 {
 142         direct_gbpages = 1;
 143         return 0;
 144 }
 145 early_param("gbpages", parse_direct_gbpages_on);
 146
 147 /*
 148  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
 149  * physical space so we can cache the place of the first one and move
 150  * around without checking the pgd every time.
 151  */
 152
 153 pteval_t __supported_pte_mask __read_mostly = ~0;
 154 EXPORT_SYMBOL_GPL(__supported_pte_mask);
 155
 156 int force_personality32;
 157
 158 /*
 159  * noexec32=on|off
 160  * Control non executable heap for 32bit processes.
 161  * To control the stack too use noexec=off
 162  *
 163  * on   PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
 164  * off  PROT_READ implies PROT_EXEC
 165  */
 166 static int __init nonx32_setup(char *str)
 167 {
 168         if (!strcmp(str, "on"))
 169                 force_personality32 &= ~READ_IMPLIES_EXEC;
 170         else if (!strcmp(str, "off"))
 171                 force_personality32 |= READ_IMPLIES_EXEC;
 172         return 1;
 173 }
 174 __setup("noexec32=", nonx32_setup);
 175
 176 /*
 177  * When memory was added/removed make sure all the processes MM have
 178  * suitable PGD entries in the local PGD level page.
 179  */
 180 void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 181 {
 182         unsigned long address;
 183
 184         for (address = start; address <= end; address += PGDIR_SIZE) {
 185                 const pgd_t *pgd_ref = pgd_offset_k(address);
 186                 struct page *page;
 187
 188                 /*
 189                  * When it is called after memory hot remove, pgd_none()
 190                  * returns true. In this case (removed == 1), we must clear
 191                  * the PGD entries in the local PGD level page.
 192                  */
 193                 if (pgd_none(*pgd_ref) && !removed)
 194                         continue;
 195
 196                 spin_lock(&pgd_lock);
 197                 list_for_each_entry(page, &pgd_list, lru) {
 198                         pgd_t *pgd;
 199                         spinlock_t *pgt_lock;
 200
 201                         pgd = (pgd_t *)page_address(page) + pgd_index(address);
 202                         /* the pgt_lock only for Xen */
 203                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
 204                         spin_lock(pgt_lock);
 205
 206                         if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
 207                                 BUG_ON(pgd_page_vaddr(*pgd)
 208                                        != pgd_page_vaddr(*pgd_ref));
 209
 210                         if (removed) {
 211                                 if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
 212                                         pgd_clear(pgd);
 213                         } else {
 214                                 if (pgd_none(*pgd))
 215                                         set_pgd(pgd, *pgd_ref);
 216                         }
 217
 218                         spin_unlock(pgt_lock);
 219                 }
 220                 spin_unlock(&pgd_lock);
 221         }
 222 }
 223
 224 /*
 225  * NOTE: This function is marked __ref because it calls __init function
 226  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
 227  */
 228 static __ref void *spp_getpage(void)
 229 {
 230         void *ptr;
 231
 232         if (after_bootmem)
 233                 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 234         else
 235                 ptr = alloc_bootmem_pages(PAGE_SIZE);
 236
 237         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
 238                 panic("set_pte_phys: cannot allocate page data %s\n",
 239                         after_bootmem ? "after bootmem" : "");
 240         }
 241
 242         pr_debug("spp_getpage %p\n", ptr);
 243
 244         return ptr;
 245 }
 246
 247 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
 248 {
 249         if (pgd_none(*pgd)) {
 250                 pud_t *pud = (pud_t *)spp_getpage();
 251                 pgd_populate(&init_mm, pgd, pud);
 252                 if (pud != pud_offset(pgd, 0))
 253                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
 254                                pud, pud_offset(pgd, 0));
 255         }
 256         return pud_offset(pgd, vaddr);
 257 }
 258
 259 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
 260 {
 261         if (pud_none(*pud)) {
 262                 pmd_t *pmd = (pmd_t *) spp_getpage();
 263                 pud_populate(&init_mm, pud, pmd);
 264                 if (pmd != pmd_offset(pud, 0))
 265                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
 266                                pmd, pmd_offset(pud, 0));
 267         }
 268         return pmd_offset(pud, vaddr);
 269 }
 270
 271 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
 272 {
 273         if (pmd_none(*pmd)) {
 274                 pte_t *pte = (pte_t *) spp_getpage();
 275                 pmd_populate_kernel(&init_mm, pmd, pte);
 276                 if (pte != pte_offset_kernel(pmd, 0))
 277                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
 278         }
 279         return pte_offset_kernel(pmd, vaddr);
 280 }
 281
 282 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
 283 {
 284         pud_t *pud;
 285         pmd_t *pmd;
 286         pte_t *pte;
 287
 288         pud = pud_page + pud_index(vaddr);
 289         pmd = fill_pmd(pud, vaddr);
 290         pte = fill_pte(pmd, vaddr);
 291
 292         set_pte(pte, new_pte);
 293
 294         /*
 295          * It's enough to flush this one mapping.
 296          * (PGE mappings get flushed as well)
 297          */
 298         __flush_tlb_one(vaddr);
 299 }
 300
 301 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
 302 {
 303         pgd_t *pgd;
 304         pud_t *pud_page;
 305
 306         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
 307
 308         pgd = pgd_offset_k(vaddr);
 309         if (pgd_none(*pgd)) {
 310                 printk(KERN_ERR
 311                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
 312                 return;
 313         }
 314         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
 315         set_pte_vaddr_pud(pud_page, vaddr, pteval);
 316 }
 317
 318 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
 319 {
 320         pgd_t *pgd;
 321         pud_t *pud;
 322
 323         pgd = pgd_offset_k(vaddr);
 324         pud = fill_pud(pgd, vaddr);
 325         return fill_pmd(pud, vaddr);
 326 }
 327
 328 pte_t * __init populate_extra_pte(unsigned long vaddr)
 329 {
 330         pmd_t *pmd;
 331
 332         pmd = populate_extra_pmd(vaddr);
 333         return fill_pte(pmd, vaddr);
 334 }
 335
 336 /*
 337  * Create large page table mappings for a range of physical addresses.
 338  */
 339 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
 340                                         enum page_cache_mode cache)
 341 {
 342         pgd_t *pgd;
 343         pud_t *pud;
 344         pmd_t *pmd;
 345         pgprot_t prot;
 346
 347         pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
 348                 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
 349         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
 350         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
 351                 pgd = pgd_offset_k((unsigned long)__va(phys));
 352                 if (pgd_none(*pgd)) {
 353                         pud = (pud_t *) spp_getpage();
 354                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
 355                                                 _PAGE_USER));
 356                 }
 357                 pud = pud_offset(pgd, (unsigned long)__va(phys));
 358                 if (pud_none(*pud)) {
 359                         pmd = (pmd_t *) spp_getpage();
 360                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
 361                                                 _PAGE_USER));
 362                 }
 363                 pmd = pmd_offset(pud, phys);
 364                 BUG_ON(!pmd_none(*pmd));
 365                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
 366         }
 367 }
 368
 369 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
 370 {
 371         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
 372 }
 373
 374 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 375 {
 376         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
 377 }
 378
 379 /*
 380  * The head.S code sets up the kernel high mapping:
 381  *
 382  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
 383  *
 384  * phys_base holds the negative offset to the kernel, which is added
 385  * to the compile time generated pmds. This results in invalid pmds up
 386  * to the point where we hit the physaddr 0 mapping.
 387  *
 388  * We limit the mappings to the region from _text to _brk_end.  _brk_end
 389  * is rounded up to the 2MB boundary. This catches the invalid pmds as
 390  * well, as they are located before _text:
 391  */
 392 void __init cleanup_highmap(void)
 393 {
 394         unsigned long vaddr = __START_KERNEL_map;
 395         unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
 396         unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
 397         pmd_t *pmd = level2_kernel_pgt;
 398
 399         /*
 400          * Native path, max_pfn_mapped is not set yet.
 401          * Xen has valid max_pfn_mapped set in
 402          *      arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
 403          */
 404         if (max_pfn_mapped)
 405                 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
 406
 407         for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
 408                 if (pmd_none(*pmd))
 409                         continue;
 410                 if (vaddr < (unsigned long) _text || vaddr > end)
 411                         set_pmd(pmd, __pmd(0));
 412         }
 413 }
 414
 415 static unsigned long __meminit
 416 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
 417               pgprot_t prot)
 418 {
 419         unsigned long pages = 0, next;
 420         unsigned long last_map_addr = end;
 421         int i;
 422
 423         pte_t *pte = pte_page + pte_index(addr);
 424
 425         for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {
 426                 next = (addr & PAGE_MASK) + PAGE_SIZE;
 427                 if (addr >= end) {
 428                         if (!after_bootmem &&
 429                             !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&
 430                             !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))
 431                                 set_pte(pte, __pte(0));
 432                         continue;
 433                 }
 434
 435                 /*
 436                  * We will re-use the existing mapping.
 437                  * Xen for example has some special requirements, like mapping
 438                  * pagetable pages as RO. So assume someone who pre-setup
 439                  * these mappings are more intelligent.
 440                  */
 441                 if (pte_val(*pte)) {
 442                         if (!after_bootmem)
 443                                 pages++;
 444                         continue;
 445                 }
 446
 447                 if (0)
 448                         printk("   pte=%p addr=%lx pte=%016lx\n",
 449                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
 450                 pages++;
 451                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
 452                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
 453         }
 454
 455         update_page_count(PG_LEVEL_4K, pages);
 456
 457         return last_map_addr;
 458 }
 459
 460 static unsigned long __meminit
 461 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 462               unsigned long page_size_mask, pgprot_t prot)
 463 {
 464         unsigned long pages = 0, next;
 465         unsigned long last_map_addr = end;
 466
 467         int i = pmd_index(address);
 468
 469         for (; i < PTRS_PER_PMD; i++, address = next) {
 470                 pmd_t *pmd = pmd_page + pmd_index(address);
 471                 pte_t *pte;
 472                 pgprot_t new_prot = prot;
 473
 474                 next = (address & PMD_MASK) + PMD_SIZE;
 475                 if (address >= end) {
 476                         if (!after_bootmem &&
 477                             !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&
 478                             !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))
 479                                 set_pmd(pmd, __pmd(0));
 480                         continue;
 481                 }
 482
 483                 if (pmd_val(*pmd)) {
 484                         if (!pmd_large(*pmd)) {
 485                                 spin_lock(&init_mm.page_table_lock);
 486                                 pte = (pte_t *)pmd_page_vaddr(*pmd);
 487                                 last_map_addr = phys_pte_init(pte, address,
 488                                                                 end, prot);
 489                                 spin_unlock(&init_mm.page_table_lock);
 490                                 continue;
 491                         }
 492                         /*
 493                          * If we are ok with PG_LEVEL_2M mapping, then we will
 494                          * use the existing mapping,
 495                          *
 496                          * Otherwise, we will split the large page mapping but
 497                          * use the same existing protection bits except for
 498                          * large page, so that we don't violate Intel's TLB
 499                          * Application note (317080) which says, while changing
 500                          * the page sizes, new and old translations should
 501                          * not differ with respect to page frame and
 502                          * attributes.
 503                          */
 504                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
 505                                 if (!after_bootmem)
 506                                         pages++;
 507                                 last_map_addr = next;
 508                                 continue;
 509                         }
 510                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
 511                 }
 512
 513                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
 514                         pages++;
 515                         spin_lock(&init_mm.page_table_lock);
 516                         set_pte((pte_t *)pmd,
 517                                 pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,
 518                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
 519                         spin_unlock(&init_mm.page_table_lock);
 520                         last_map_addr = next;
 521                         continue;
 522                 }
 523
 524                 pte = alloc_low_page();
 525                 last_map_addr = phys_pte_init(pte, address, end, new_prot);
 526
 527                 spin_lock(&init_mm.page_table_lock);
 528                 pmd_populate_kernel(&init_mm, pmd, pte);
 529                 spin_unlock(&init_mm.page_table_lock);
 530         }
 531         update_page_count(PG_LEVEL_2M, pages);
 532         return last_map_addr;
 533 }
 534
 535 static unsigned long __meminit
 536 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
 537                          unsigned long page_size_mask)
 538 {
 539         unsigned long pages = 0, next;
 540         unsigned long last_map_addr = end;
 541         int i = pud_index(addr);
 542
 543         for (; i < PTRS_PER_PUD; i++, addr = next) {
 544                 pud_t *pud = pud_page + pud_index(addr);
 545                 pmd_t *pmd;
 546                 pgprot_t prot = PAGE_KERNEL;
 547
 548                 next = (addr & PUD_MASK) + PUD_SIZE;
 549                 if (addr >= end) {
 550                         if (!after_bootmem &&
 551                             !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&
 552                             !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))
 553                                 set_pud(pud, __pud(0));
 554                         continue;
 555                 }
 556
 557                 if (pud_val(*pud)) {
 558                         if (!pud_large(*pud)) {
 559                                 pmd = pmd_offset(pud, 0);
 560                                 last_map_addr = phys_pmd_init(pmd, addr, end,
 561                                                          page_size_mask, prot);
 562                                 __flush_tlb_all();
 563                                 continue;
 564                         }
 565                         /*
 566                          * If we are ok with PG_LEVEL_1G mapping, then we will
 567                          * use the existing mapping.
 568                          *
 569                          * Otherwise, we will split the gbpage mapping but use
 570                          * the same existing protection  bits except for large
 571                          * page, so that we don't violate Intel's TLB
 572                          * Application note (317080) which says, while changing
 573                          * the page sizes, new and old translations should
 574                          * not differ with respect to page frame and
 575                          * attributes.
 576                          */
 577                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
 578                                 if (!after_bootmem)
 579                                         pages++;
 580                                 last_map_addr = next;
 581                                 continue;
 582                         }
 583                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
 584                 }
 585
 586                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
 587                         pages++;
 588                         spin_lock(&init_mm.page_table_lock);
 589                         set_pte((pte_t *)pud,
 590                                 pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,
 591                                         PAGE_KERNEL_LARGE));
 592                         spin_unlock(&init_mm.page_table_lock);
 593                         last_map_addr = next;
 594                         continue;
 595                 }
 596
 597                 pmd = alloc_low_page();
 598                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
 599                                               prot);
 600
 601                 spin_lock(&init_mm.page_table_lock);
 602                 pud_populate(&init_mm, pud, pmd);
 603                 spin_unlock(&init_mm.page_table_lock);
 604         }
 605         __flush_tlb_all();
 606
 607         update_page_count(PG_LEVEL_1G, pages);
 608
 609         return last_map_addr;
 610 }
 611
 612 unsigned long __meminit
 613 kernel_physical_mapping_init(unsigned long start,
 614                              unsigned long end,
 615                              unsigned long page_size_mask)
 616 {
 617         bool pgd_changed = false;
 618         unsigned long next, last_map_addr = end;
 619         unsigned long addr;
 620
 621         start = (unsigned long)__va(start);
 622         end = (unsigned long)__va(end);
 623         addr = start;
 624
 625         for (; start < end; start = next) {
 626                 pgd_t *pgd = pgd_offset_k(start);
 627                 pud_t *pud;
 628
 629                 next = (start & PGDIR_MASK) + PGDIR_SIZE;
 630
 631                 if (pgd_val(*pgd)) {
 632                         pud = (pud_t *)pgd_page_vaddr(*pgd);
 633                         last_map_addr = phys_pud_init(pud, __pa(start),
 634                                                  __pa(end), page_size_mask);
 635                         continue;
 636                 }
 637
 638                 pud = alloc_low_page();
 639                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),
 640                                                  page_size_mask);
 641
 642                 spin_lock(&init_mm.page_table_lock);
 643                 pgd_populate(&init_mm, pgd, pud);
 644                 spin_unlock(&init_mm.page_table_lock);
 645                 pgd_changed = true;
 646         }
 647
 648         if (pgd_changed)
 649                 sync_global_pgds(addr, end - 1, 0);
 650
 651         __flush_tlb_all();
 652
 653         return last_map_addr;
 654 }
 655
 656 #ifndef CONFIG_NUMA
 657 void __init initmem_init(void)
 658 {
 659         memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
 660 }
 661 #endif
 662
 663 void __init paging_init(void)
 664 {
 665         sparse_memory_present_with_active_regions(MAX_NUMNODES);
 666         sparse_init();
 667
 668         /*
 669          * clear the default setting with node 0
 670          * note: don't use nodes_clear here, that is really clearing when
 671          *       numa support is not compiled in, and later node_set_state
 672          *       will not set it back.
 673          */
 674         node_clear_state(0, N_MEMORY);
 675         if (N_MEMORY != N_NORMAL_MEMORY)
 676                 node_clear_state(0, N_NORMAL_MEMORY);
 677
 678         zone_sizes_init();
 679 }
 680
 681 /*
 682  * Memory hotplug specific functions
 683  */
 684 #ifdef CONFIG_MEMORY_HOTPLUG
 685 /*
 686  * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
 687  * updating.
 688  */
 689 static void  update_end_of_memory_vars(u64 start, u64 size)
 690 {
 691         unsigned long end_pfn = PFN_UP(start + size);
 692
 693         if (end_pfn > max_pfn) {
 694                 max_pfn = end_pfn;
 695                 max_low_pfn = end_pfn;
 696                 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 697         }
 698 }
 699
 700 /*
 701  * Memory is added always to NORMAL zone. This means you will never get
 702  * additional DMA/DMA32 memory.
 703  */
 704 int arch_add_memory(int nid, u64 start, u64 size)
 705 {
 706         struct pglist_data *pgdat = NODE_DATA(nid);
 707         struct zone *zone = pgdat->node_zones +
 708                 zone_for_memory(nid, start, size, ZONE_NORMAL);
 709         unsigned long start_pfn = start >> PAGE_SHIFT;
 710         unsigned long nr_pages = size >> PAGE_SHIFT;
 711         int ret;
 712
 713         init_memory_mapping(start, start + size);
 714
 715         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 716         WARN_ON_ONCE(ret);
 717
 718         /* update max_pfn, max_low_pfn and high_memory */
 719         update_end_of_memory_vars(start, size);
 720
 721         return ret;
 722 }
 723 EXPORT_SYMBOL_GPL(arch_add_memory);
 724
 725 #define PAGE_INUSE 0xFD
 726
 727 static void __meminit free_pagetable(struct page *page, int order)
 728 {
 729         unsigned long magic;
 730         unsigned int nr_pages = 1 << order;
 731
 732         /* bootmem page has reserved flag */
 733         if (PageReserved(page)) {
 734                 __ClearPageReserved(page);
 735
 736                 magic = (unsigned long)page->lru.next;
 737                 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
 738                         while (nr_pages--)
 739                                 put_page_bootmem(page++);
 740                 } else
 741                         while (nr_pages--)
 742                                 free_reserved_page(page++);
 743         } else
 744                 free_pages((unsigned long)page_address(page), order);
 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         unsigned long addr;
 993         pgd_t *pgd;
 994         pud_t *pud;
 995         bool pgd_changed = false;
 996
 997         for (addr = start; addr < end; addr = next) {
 998                 next = pgd_addr_end(addr, end);
 999
1000                 pgd = pgd_offset_k(addr);
1001                 if (!pgd_present(*pgd))
1002                         continue;
1003
1004                 pud = (pud_t *)pgd_page_vaddr(*pgd);
1005                 remove_pud_table(pud, addr, next, direct);
1006                 if (free_pud_table(pud, pgd))
1007                         pgd_changed = true;
1008         }
1009
1010         if (pgd_changed)
1011                 sync_global_pgds(start, end - 1, 1);
1012
1013         flush_tlb_all();
1014 }
1015
1016 void __ref vmemmap_free(unsigned long start, unsigned long end)
1017 {
1018         remove_pagetable(start, end, false);
1019 }
1020
1021 #ifdef CONFIG_MEMORY_HOTREMOVE
1022 static void __meminit
1023 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1024 {
1025         start = (unsigned long)__va(start);
1026         end = (unsigned long)__va(end);
1027
1028         remove_pagetable(start, end, true);
1029 }
1030
1031 int __ref arch_remove_memory(u64 start, u64 size)
1032 {
1033         unsigned long start_pfn = start >> PAGE_SHIFT;
1034         unsigned long nr_pages = size >> PAGE_SHIFT;
1035         struct zone *zone;
1036         int ret;
1037
1038         zone = page_zone(pfn_to_page(start_pfn));
1039         kernel_physical_mapping_remove(start, start + size);
1040         ret = __remove_pages(zone, start_pfn, nr_pages);
1041         WARN_ON_ONCE(ret);
1042
1043         return ret;
1044 }
1045 #endif
1046 #endif /* CONFIG_MEMORY_HOTPLUG */
1047
1048 static struct kcore_list kcore_vsyscall;
1049
1050 static void __init register_page_bootmem_info(void)
1051 {
1052 #ifdef CONFIG_NUMA
1053         int i;
1054
1055         for_each_online_node(i)
1056                 register_page_bootmem_info_node(NODE_DATA(i));
1057 #endif
1058 }
1059
1060 void __init mem_init(void)
1061 {
1062         pci_iommu_alloc();
1063
1064         /* clear_bss() already clear the empty_zero_page */
1065
1066         register_page_bootmem_info();
1067
1068         /* this will put all memory onto the freelists */
1069         free_all_bootmem();
1070         after_bootmem = 1;
1071
1072         /* Register memory areas for /proc/kcore */
1073         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR,
1074                          PAGE_SIZE, KCORE_OTHER);
1075
1076         mem_init_print_info(NULL);
1077 }
1078
1079 #ifdef CONFIG_DEBUG_RODATA
1080 const int rodata_test_data = 0xC3;
1081 EXPORT_SYMBOL_GPL(rodata_test_data);
1082
1083 int kernel_set_to_readonly;
1084
1085 void set_kernel_text_rw(void)
1086 {
1087         unsigned long start = PFN_ALIGN(_text);
1088         unsigned long end = PFN_ALIGN(__stop___ex_table);
1089
1090         if (!kernel_set_to_readonly)
1091                 return;
1092
1093         pr_debug("Set kernel text: %lx - %lx for read write\n",
1094                  start, end);
1095
1096         /*
1097          * Make the kernel identity mapping for text RW. Kernel text
1098          * mapping will always be RO. Refer to the comment in
1099          * static_protections() in pageattr.c
1100          */
1101         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1102 }
1103
1104 void set_kernel_text_ro(void)
1105 {
1106         unsigned long start = PFN_ALIGN(_text);
1107         unsigned long end = PFN_ALIGN(__stop___ex_table);
1108
1109         if (!kernel_set_to_readonly)
1110                 return;
1111
1112         pr_debug("Set kernel text: %lx - %lx for read only\n",
1113                  start, end);
1114
1115         /*
1116          * Set the kernel identity mapping for text RO.
1117          */
1118         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1119 }
1120
1121 void mark_rodata_ro(void)
1122 {
1123         unsigned long start = PFN_ALIGN(_text);
1124         unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1125         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1126         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1127         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1128         unsigned long all_end = PFN_ALIGN(&_end);
1129
1130         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1131                (end - start) >> 10);
1132         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1133
1134         kernel_set_to_readonly = 1;
1135
1136         /*
1137          * The rodata/data/bss/brk section (but not the kernel text!)
1138          * should also be not-executable.
1139          */
1140         set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
1141
1142         rodata_test();
1143
1144 #ifdef CONFIG_CPA_DEBUG
1145         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1146         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1147
1148         printk(KERN_INFO "Testing CPA: again\n");
1149         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1150 #endif
1151
1152         free_init_pages("unused kernel",
1153                         (unsigned long) __va(__pa_symbol(text_end)),
1154                         (unsigned long) __va(__pa_symbol(rodata_start)));
1155         free_init_pages("unused kernel",
1156                         (unsigned long) __va(__pa_symbol(rodata_end)),
1157                         (unsigned long) __va(__pa_symbol(_sdata)));
1158 }
1159
1160 #endif
1161
1162 int kern_addr_valid(unsigned long addr)
1163 {
1164         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1165         pgd_t *pgd;
1166         pud_t *pud;
1167         pmd_t *pmd;
1168         pte_t *pte;
1169
1170         if (above != 0 && above != -1UL)
1171                 return 0;
1172
1173         pgd = pgd_offset_k(addr);
1174         if (pgd_none(*pgd))
1175                 return 0;
1176
1177         pud = pud_offset(pgd, addr);
1178         if (pud_none(*pud))
1179                 return 0;
1180
1181         if (pud_large(*pud))
1182                 return pfn_valid(pud_pfn(*pud));
1183
1184         pmd = pmd_offset(pud, addr);
1185         if (pmd_none(*pmd))
1186                 return 0;
1187
1188         if (pmd_large(*pmd))
1189                 return pfn_valid(pmd_pfn(*pmd));
1190
1191         pte = pte_offset_kernel(pmd, addr);
1192         if (pte_none(*pte))
1193                 return 0;
1194
1195         return pfn_valid(pte_pfn(*pte));
1196 }
1197
1198 /*
1199  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
1200  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1201  * not need special handling anymore:
1202  */
1203 static const char *gate_vma_name(struct vm_area_struct *vma)
1204 {
1205         return "[vsyscall]";
1206 }
1207 static struct vm_operations_struct gate_vma_ops = {
1208         .name = gate_vma_name,
1209 };
1210 static struct vm_area_struct gate_vma = {
1211         .vm_start       = VSYSCALL_ADDR,
1212         .vm_end         = VSYSCALL_ADDR + PAGE_SIZE,
1213         .vm_page_prot   = PAGE_READONLY_EXEC,
1214         .vm_flags       = VM_READ | VM_EXEC,
1215         .vm_ops         = &gate_vma_ops,
1216 };
1217
1218 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
1219 {
1220 #ifdef CONFIG_IA32_EMULATION
1221         if (!mm || mm->context.ia32_compat)
1222                 return NULL;
1223 #endif
1224         return &gate_vma;
1225 }
1226
1227 int in_gate_area(struct mm_struct *mm, unsigned long addr)
1228 {
1229         struct vm_area_struct *vma = get_gate_vma(mm);
1230
1231         if (!vma)
1232                 return 0;
1233
1234         return (addr >= vma->vm_start) && (addr < vma->vm_end);
1235 }
1236
1237 /*
1238  * Use this when you have no reliable mm, typically from interrupt
1239  * context. It is less reliable than using a task's mm and may give
1240  * false positives.
1241  */
1242 int in_gate_area_no_mm(unsigned long addr)
1243 {
1244         return (addr & PAGE_MASK) == VSYSCALL_ADDR;
1245 }
1246
1247 static unsigned long probe_memory_block_size(void)
1248 {
1249         /* start from 2g */
1250         unsigned long bz = 1UL<<31;
1251
1252         if (totalram_pages >= (64ULL << (30 - PAGE_SHIFT))) {
1253                 pr_info("Using 2GB memory block size for large-memory system\n");
1254                 return 2UL * 1024 * 1024 * 1024;
1255         }
1256
1257         /* less than 64g installed */
1258         if ((max_pfn << PAGE_SHIFT) < (16UL << 32))
1259                 return MIN_MEMORY_BLOCK_SIZE;
1260
1261         /* get the tail size */
1262         while (bz > MIN_MEMORY_BLOCK_SIZE) {
1263                 if (!((max_pfn << PAGE_SHIFT) & (bz - 1)))
1264                         break;
1265                 bz >>= 1;
1266         }
1267
1268         printk(KERN_DEBUG "memory block size : %ldMB\n", bz >> 20);
1269
1270         return bz;
1271 }
1272
1273 static unsigned long memory_block_size_probed;
1274 unsigned long memory_block_size_bytes(void)
1275 {
1276         if (!memory_block_size_probed)
1277                 memory_block_size_probed = probe_memory_block_size();
1278
1279         return memory_block_size_probed;
1280 }
1281
1282 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1283 /*
1284  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1285  */
1286 static long __meminitdata addr_start, addr_end;
1287 static void __meminitdata *p_start, *p_end;
1288 static int __meminitdata node_start;
1289
1290 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1291                                                 unsigned long end, int node)
1292 {
1293         unsigned long addr;
1294         unsigned long next;
1295         pgd_t *pgd;
1296         pud_t *pud;
1297         pmd_t *pmd;
1298
1299         for (addr = start; addr < end; addr = next) {
1300                 next = pmd_addr_end(addr, end);
1301
1302                 pgd = vmemmap_pgd_populate(addr, node);
1303                 if (!pgd)
1304                         return -ENOMEM;
1305
1306                 pud = vmemmap_pud_populate(pgd, addr, node);
1307                 if (!pud)
1308                         return -ENOMEM;
1309
1310                 pmd = pmd_offset(pud, addr);
1311                 if (pmd_none(*pmd)) {
1312                         void *p;
1313
1314                         p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1315                         if (p) {
1316                                 pte_t entry;
1317
1318                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1319                                                 PAGE_KERNEL_LARGE);
1320                                 set_pmd(pmd, __pmd(pte_val(entry)));
1321
1322                                 /* check to see if we have contiguous blocks */
1323                                 if (p_end != p || node_start != node) {
1324                                         if (p_start)
1325                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1326                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1327                                         addr_start = addr;
1328                                         node_start = node;
1329                                         p_start = p;
1330                                 }
1331
1332                                 addr_end = addr + PMD_SIZE;
1333                                 p_end = p + PMD_SIZE;
1334                                 continue;
1335                         }
1336                 } else if (pmd_large(*pmd)) {
1337                         vmemmap_verify((pte_t *)pmd, node, addr, next);
1338                         continue;
1339                 }
1340                 pr_warn_once("vmemmap: falling back to regular page backing\n");
1341                 if (vmemmap_populate_basepages(addr, next, node))
1342                         return -ENOMEM;
1343         }
1344         return 0;
1345 }
1346
1347 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1348 {
1349         int err;
1350
1351         if (cpu_has_pse)
1352                 err = vmemmap_populate_hugepages(start, end, node);
1353         else
1354                 err = vmemmap_populate_basepages(start, end, node);
1355         if (!err)
1356                 sync_global_pgds(start, end - 1, 0);
1357         return err;
1358 }
1359
1360 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1361 void register_page_bootmem_memmap(unsigned long section_nr,
1362                                   struct page *start_page, unsigned long size)
1363 {
1364         unsigned long addr = (unsigned long)start_page;
1365         unsigned long end = (unsigned long)(start_page + size);
1366         unsigned long next;
1367         pgd_t *pgd;
1368         pud_t *pud;
1369         pmd_t *pmd;
1370         unsigned int nr_pages;
1371         struct page *page;
1372
1373         for (; addr < end; addr = next) {
1374                 pte_t *pte = NULL;
1375
1376                 pgd = pgd_offset_k(addr);
1377                 if (pgd_none(*pgd)) {
1378                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1379                         continue;
1380                 }
1381                 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1382
1383                 pud = pud_offset(pgd, addr);
1384                 if (pud_none(*pud)) {
1385                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1386                         continue;
1387                 }
1388                 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1389
1390                 if (!cpu_has_pse) {
1391                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1392                         pmd = pmd_offset(pud, addr);
1393                         if (pmd_none(*pmd))
1394                                 continue;
1395                         get_page_bootmem(section_nr, pmd_page(*pmd),
1396                                          MIX_SECTION_INFO);
1397
1398                         pte = pte_offset_kernel(pmd, addr);
1399                         if (pte_none(*pte))
1400                                 continue;
1401                         get_page_bootmem(section_nr, pte_page(*pte),
1402                                          SECTION_INFO);
1403                 } else {
1404                         next = pmd_addr_end(addr, end);
1405
1406                         pmd = pmd_offset(pud, addr);
1407                         if (pmd_none(*pmd))
1408                                 continue;
1409
1410                         nr_pages = 1 << (get_order(PMD_SIZE));
1411                         page = pmd_page(*pmd);
1412                         while (nr_pages--)
1413                                 get_page_bootmem(section_nr, page++,
1414                                                  SECTION_INFO);
1415                 }
1416         }
1417 }
1418 #endif
1419
1420 void __meminit vmemmap_populate_print_last(void)
1421 {
1422         if (p_start) {
1423                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1424                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1425                 p_start = NULL;
1426                 p_end = NULL;
1427                 node_start = 0;
1428         }
1429 }
1430 #endif