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/memory.h>
  31 #include <linux/memory_hotplug.h>
  32 #include <linux/memremap.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 <linux/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 #include "ident_map.c"
  61
  62 /*
  63  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
  64  * physical space so we can cache the place of the first one and move
  65  * around without checking the pgd every time.
  66  */
  67
  68 pteval_t __supported_pte_mask __read_mostly = ~0;
  69 EXPORT_SYMBOL_GPL(__supported_pte_mask);
  70
  71 int force_personality32;
  72
  73 /*
  74  * noexec32=on|off
  75  * Control non executable heap for 32bit processes.
  76  * To control the stack too use noexec=off
  77  *
  78  * on   PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
  79  * off  PROT_READ implies PROT_EXEC
  80  */
  81 static int __init nonx32_setup(char *str)
  82 {
  83         if (!strcmp(str, "on"))
  84                 force_personality32 &= ~READ_IMPLIES_EXEC;
  85         else if (!strcmp(str, "off"))
  86                 force_personality32 |= READ_IMPLIES_EXEC;
  87         return 1;
  88 }
  89 __setup("noexec32=", nonx32_setup);
  90
  91 /*
  92  * When memory was added make sure all the processes MM have
  93  * suitable PGD entries in the local PGD level page.
  94  */
  95 void sync_global_pgds(unsigned long start, unsigned long end)
  96 {
  97         unsigned long address;
  98
  99         for (address = start; address <= end; address += PGDIR_SIZE) {
 100                 const pgd_t *pgd_ref = pgd_offset_k(address);
 101                 struct page *page;
 102
 103                 if (pgd_none(*pgd_ref))
 104                         continue;
 105
 106                 spin_lock(&pgd_lock);
 107                 list_for_each_entry(page, &pgd_list, lru) {
 108                         pgd_t *pgd;
 109                         spinlock_t *pgt_lock;
 110
 111                         pgd = (pgd_t *)page_address(page) + pgd_index(address);
 112                         /* the pgt_lock only for Xen */
 113                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
 114                         spin_lock(pgt_lock);
 115
 116                         if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
 117                                 BUG_ON(pgd_page_vaddr(*pgd)
 118                                        != pgd_page_vaddr(*pgd_ref));
 119
 120                         if (pgd_none(*pgd))
 121                                 set_pgd(pgd, *pgd_ref);
 122
 123                         spin_unlock(pgt_lock);
 124                 }
 125                 spin_unlock(&pgd_lock);
 126         }
 127 }
 128
 129 /*
 130  * NOTE: This function is marked __ref because it calls __init function
 131  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
 132  */
 133 static __ref void *spp_getpage(void)
 134 {
 135         void *ptr;
 136
 137         if (after_bootmem)
 138                 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 139         else
 140                 ptr = alloc_bootmem_pages(PAGE_SIZE);
 141
 142         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
 143                 panic("set_pte_phys: cannot allocate page data %s\n",
 144                         after_bootmem ? "after bootmem" : "");
 145         }
 146
 147         pr_debug("spp_getpage %p\n", ptr);
 148
 149         return ptr;
 150 }
 151
 152 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
 153 {
 154         if (pgd_none(*pgd)) {
 155                 pud_t *pud = (pud_t *)spp_getpage();
 156                 pgd_populate(&init_mm, pgd, pud);
 157                 if (pud != pud_offset(pgd, 0))
 158                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
 159                                pud, pud_offset(pgd, 0));
 160         }
 161         return pud_offset(pgd, vaddr);
 162 }
 163
 164 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
 165 {
 166         if (pud_none(*pud)) {
 167                 pmd_t *pmd = (pmd_t *) spp_getpage();
 168                 pud_populate(&init_mm, pud, pmd);
 169                 if (pmd != pmd_offset(pud, 0))
 170                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
 171                                pmd, pmd_offset(pud, 0));
 172         }
 173         return pmd_offset(pud, vaddr);
 174 }
 175
 176 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
 177 {
 178         if (pmd_none(*pmd)) {
 179                 pte_t *pte = (pte_t *) spp_getpage();
 180                 pmd_populate_kernel(&init_mm, pmd, pte);
 181                 if (pte != pte_offset_kernel(pmd, 0))
 182                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
 183         }
 184         return pte_offset_kernel(pmd, vaddr);
 185 }
 186
 187 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
 188 {
 189         pud_t *pud;
 190         pmd_t *pmd;
 191         pte_t *pte;
 192
 193         pud = pud_page + pud_index(vaddr);
 194         pmd = fill_pmd(pud, vaddr);
 195         pte = fill_pte(pmd, vaddr);
 196
 197         set_pte(pte, new_pte);
 198
 199         /*
 200          * It's enough to flush this one mapping.
 201          * (PGE mappings get flushed as well)
 202          */
 203         __flush_tlb_one(vaddr);
 204 }
 205
 206 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
 207 {
 208         pgd_t *pgd;
 209         pud_t *pud_page;
 210
 211         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
 212
 213         pgd = pgd_offset_k(vaddr);
 214         if (pgd_none(*pgd)) {
 215                 printk(KERN_ERR
 216                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
 217                 return;
 218         }
 219         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
 220         set_pte_vaddr_pud(pud_page, vaddr, pteval);
 221 }
 222
 223 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
 224 {
 225         pgd_t *pgd;
 226         pud_t *pud;
 227
 228         pgd = pgd_offset_k(vaddr);
 229         pud = fill_pud(pgd, vaddr);
 230         return fill_pmd(pud, vaddr);
 231 }
 232
 233 pte_t * __init populate_extra_pte(unsigned long vaddr)
 234 {
 235         pmd_t *pmd;
 236
 237         pmd = populate_extra_pmd(vaddr);
 238         return fill_pte(pmd, vaddr);
 239 }
 240
 241 /*
 242  * Create large page table mappings for a range of physical addresses.
 243  */
 244 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
 245                                         enum page_cache_mode cache)
 246 {
 247         pgd_t *pgd;
 248         pud_t *pud;
 249         pmd_t *pmd;
 250         pgprot_t prot;
 251
 252         pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
 253                 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
 254         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
 255         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
 256                 pgd = pgd_offset_k((unsigned long)__va(phys));
 257                 if (pgd_none(*pgd)) {
 258                         pud = (pud_t *) spp_getpage();
 259                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
 260                                                 _PAGE_USER));
 261                 }
 262                 pud = pud_offset(pgd, (unsigned long)__va(phys));
 263                 if (pud_none(*pud)) {
 264                         pmd = (pmd_t *) spp_getpage();
 265                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
 266                                                 _PAGE_USER));
 267                 }
 268                 pmd = pmd_offset(pud, phys);
 269                 BUG_ON(!pmd_none(*pmd));
 270                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
 271         }
 272 }
 273
 274 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
 275 {
 276         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
 277 }
 278
 279 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 280 {
 281         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
 282 }
 283
 284 /*
 285  * The head.S code sets up the kernel high mapping:
 286  *
 287  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
 288  *
 289  * phys_base holds the negative offset to the kernel, which is added
 290  * to the compile time generated pmds. This results in invalid pmds up
 291  * to the point where we hit the physaddr 0 mapping.
 292  *
 293  * We limit the mappings to the region from _text to _brk_end.  _brk_end
 294  * is rounded up to the 2MB boundary. This catches the invalid pmds as
 295  * well, as they are located before _text:
 296  */
 297 void __init cleanup_highmap(void)
 298 {
 299         unsigned long vaddr = __START_KERNEL_map;
 300         unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
 301         unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
 302         pmd_t *pmd = level2_kernel_pgt;
 303
 304         /*
 305          * Native path, max_pfn_mapped is not set yet.
 306          * Xen has valid max_pfn_mapped set in
 307          *      arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
 308          */
 309         if (max_pfn_mapped)
 310                 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
 311
 312         for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
 313                 if (pmd_none(*pmd))
 314                         continue;
 315                 if (vaddr < (unsigned long) _text || vaddr > end)
 316                         set_pmd(pmd, __pmd(0));
 317         }
 318 }
 319
 320 /*
 321  * Create PTE level page table mapping for physical addresses.
 322  * It returns the last physical address mapped.
 323  */
 324 static unsigned long __meminit
 325 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
 326               pgprot_t prot)
 327 {
 328         unsigned long pages = 0, paddr_next;
 329         unsigned long paddr_last = paddr_end;
 330         pte_t *pte;
 331         int i;
 332
 333         pte = pte_page + pte_index(paddr);
 334         i = pte_index(paddr);
 335
 336         for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
 337                 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
 338                 if (paddr >= paddr_end) {
 339                         if (!after_bootmem &&
 340                             !e820_any_mapped(paddr & PAGE_MASK, paddr_next,
 341                                              E820_RAM) &&
 342                             !e820_any_mapped(paddr & PAGE_MASK, paddr_next,
 343                                              E820_RESERVED_KERN))
 344                                 set_pte(pte, __pte(0));
 345                         continue;
 346                 }
 347
 348                 /*
 349                  * We will re-use the existing mapping.
 350                  * Xen for example has some special requirements, like mapping
 351                  * pagetable pages as RO. So assume someone who pre-setup
 352                  * these mappings are more intelligent.
 353                  */
 354                 if (!pte_none(*pte)) {
 355                         if (!after_bootmem)
 356                                 pages++;
 357                         continue;
 358                 }
 359
 360                 if (0)
 361                         pr_info("   pte=%p addr=%lx pte=%016lx\n", pte, paddr,
 362                                 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
 363                 pages++;
 364                 set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));
 365                 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
 366         }
 367
 368         update_page_count(PG_LEVEL_4K, pages);
 369
 370         return paddr_last;
 371 }
 372
 373 /*
 374  * Create PMD level page table mapping for physical addresses. The virtual
 375  * and physical address have to be aligned at this level.
 376  * It returns the last physical address mapped.
 377  */
 378 static unsigned long __meminit
 379 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
 380               unsigned long page_size_mask, pgprot_t prot)
 381 {
 382         unsigned long pages = 0, paddr_next;
 383         unsigned long paddr_last = paddr_end;
 384
 385         int i = pmd_index(paddr);
 386
 387         for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
 388                 pmd_t *pmd = pmd_page + pmd_index(paddr);
 389                 pte_t *pte;
 390                 pgprot_t new_prot = prot;
 391
 392                 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
 393                 if (paddr >= paddr_end) {
 394                         if (!after_bootmem &&
 395                             !e820_any_mapped(paddr & PMD_MASK, paddr_next,
 396                                              E820_RAM) &&
 397                             !e820_any_mapped(paddr & PMD_MASK, paddr_next,
 398                                              E820_RESERVED_KERN))
 399                                 set_pmd(pmd, __pmd(0));
 400                         continue;
 401                 }
 402
 403                 if (!pmd_none(*pmd)) {
 404                         if (!pmd_large(*pmd)) {
 405                                 spin_lock(&init_mm.page_table_lock);
 406                                 pte = (pte_t *)pmd_page_vaddr(*pmd);
 407                                 paddr_last = phys_pte_init(pte, paddr,
 408                                                            paddr_end, prot);
 409                                 spin_unlock(&init_mm.page_table_lock);
 410                                 continue;
 411                         }
 412                         /*
 413                          * If we are ok with PG_LEVEL_2M mapping, then we will
 414                          * use the existing mapping,
 415                          *
 416                          * Otherwise, we will split the large page mapping but
 417                          * use the same existing protection bits except for
 418                          * large page, so that we don't violate Intel's TLB
 419                          * Application note (317080) which says, while changing
 420                          * the page sizes, new and old translations should
 421                          * not differ with respect to page frame and
 422                          * attributes.
 423                          */
 424                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
 425                                 if (!after_bootmem)
 426                                         pages++;
 427                                 paddr_last = paddr_next;
 428                                 continue;
 429                         }
 430                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
 431                 }
 432
 433                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
 434                         pages++;
 435                         spin_lock(&init_mm.page_table_lock);
 436                         set_pte((pte_t *)pmd,
 437                                 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
 438                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
 439                         spin_unlock(&init_mm.page_table_lock);
 440                         paddr_last = paddr_next;
 441                         continue;
 442                 }
 443
 444                 pte = alloc_low_page();
 445                 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot);
 446
 447                 spin_lock(&init_mm.page_table_lock);
 448                 pmd_populate_kernel(&init_mm, pmd, pte);
 449                 spin_unlock(&init_mm.page_table_lock);
 450         }
 451         update_page_count(PG_LEVEL_2M, pages);
 452         return paddr_last;
 453 }
 454
 455 /*
 456  * Create PUD level page table mapping for physical addresses. The virtual
 457  * and physical address do not have to be aligned at this level. KASLR can
 458  * randomize virtual addresses up to this level.
 459  * It returns the last physical address mapped.
 460  */
 461 static unsigned long __meminit
 462 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
 463               unsigned long page_size_mask)
 464 {
 465         unsigned long pages = 0, paddr_next;
 466         unsigned long paddr_last = paddr_end;
 467         unsigned long vaddr = (unsigned long)__va(paddr);
 468         int i = pud_index(vaddr);
 469
 470         for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
 471                 pud_t *pud;
 472                 pmd_t *pmd;
 473                 pgprot_t prot = PAGE_KERNEL;
 474
 475                 vaddr = (unsigned long)__va(paddr);
 476                 pud = pud_page + pud_index(vaddr);
 477                 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
 478
 479                 if (paddr >= paddr_end) {
 480                         if (!after_bootmem &&
 481                             !e820_any_mapped(paddr & PUD_MASK, paddr_next,
 482                                              E820_RAM) &&
 483                             !e820_any_mapped(paddr & PUD_MASK, paddr_next,
 484                                              E820_RESERVED_KERN))
 485                                 set_pud(pud, __pud(0));
 486                         continue;
 487                 }
 488
 489                 if (!pud_none(*pud)) {
 490                         if (!pud_large(*pud)) {
 491                                 pmd = pmd_offset(pud, 0);
 492                                 paddr_last = phys_pmd_init(pmd, paddr,
 493                                                            paddr_end,
 494                                                            page_size_mask,
 495                                                            prot);
 496                                 __flush_tlb_all();
 497                                 continue;
 498                         }
 499                         /*
 500                          * If we are ok with PG_LEVEL_1G mapping, then we will
 501                          * use the existing mapping.
 502                          *
 503                          * Otherwise, we will split the gbpage mapping but use
 504                          * the same existing protection  bits except for large
 505                          * page, so that we don't violate Intel's TLB
 506                          * Application note (317080) which says, while changing
 507                          * the page sizes, new and old translations should
 508                          * not differ with respect to page frame and
 509                          * attributes.
 510                          */
 511                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
 512                                 if (!after_bootmem)
 513                                         pages++;
 514                                 paddr_last = paddr_next;
 515                                 continue;
 516                         }
 517                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
 518                 }
 519
 520                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
 521                         pages++;
 522                         spin_lock(&init_mm.page_table_lock);
 523                         set_pte((pte_t *)pud,
 524                                 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
 525                                         PAGE_KERNEL_LARGE));
 526                         spin_unlock(&init_mm.page_table_lock);
 527                         paddr_last = paddr_next;
 528                         continue;
 529                 }
 530
 531                 pmd = alloc_low_page();
 532                 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
 533                                            page_size_mask, prot);
 534
 535                 spin_lock(&init_mm.page_table_lock);
 536                 pud_populate(&init_mm, pud, pmd);
 537                 spin_unlock(&init_mm.page_table_lock);
 538         }
 539         __flush_tlb_all();
 540
 541         update_page_count(PG_LEVEL_1G, pages);
 542
 543         return paddr_last;
 544 }
 545
 546 /*
 547  * Create page table mapping for the physical memory for specific physical
 548  * addresses. The virtual and physical addresses have to be aligned on PMD level
 549  * down. It returns the last physical address mapped.
 550  */
 551 unsigned long __meminit
 552 kernel_physical_mapping_init(unsigned long paddr_start,
 553                              unsigned long paddr_end,
 554                              unsigned long page_size_mask)
 555 {
 556         bool pgd_changed = false;
 557         unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
 558
 559         paddr_last = paddr_end;
 560         vaddr = (unsigned long)__va(paddr_start);
 561         vaddr_end = (unsigned long)__va(paddr_end);
 562         vaddr_start = vaddr;
 563
 564         for (; vaddr < vaddr_end; vaddr = vaddr_next) {
 565                 pgd_t *pgd = pgd_offset_k(vaddr);
 566                 pud_t *pud;
 567
 568                 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
 569
 570                 if (pgd_val(*pgd)) {
 571                         pud = (pud_t *)pgd_page_vaddr(*pgd);
 572                         paddr_last = phys_pud_init(pud, __pa(vaddr),
 573                                                    __pa(vaddr_end),
 574                                                    page_size_mask);
 575                         continue;
 576                 }
 577
 578                 pud = alloc_low_page();
 579                 paddr_last = phys_pud_init(pud, __pa(vaddr), __pa(vaddr_end),
 580                                            page_size_mask);
 581
 582                 spin_lock(&init_mm.page_table_lock);
 583                 pgd_populate(&init_mm, pgd, pud);
 584                 spin_unlock(&init_mm.page_table_lock);
 585                 pgd_changed = true;
 586         }
 587
 588         if (pgd_changed)
 589                 sync_global_pgds(vaddr_start, vaddr_end - 1);
 590
 591         __flush_tlb_all();
 592
 593         return paddr_last;
 594 }
 595
 596 #ifndef CONFIG_NUMA
 597 void __init initmem_init(void)
 598 {
 599         memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
 600 }
 601 #endif
 602
 603 void __init paging_init(void)
 604 {
 605         sparse_memory_present_with_active_regions(MAX_NUMNODES);
 606         sparse_init();
 607
 608         /*
 609          * clear the default setting with node 0
 610          * note: don't use nodes_clear here, that is really clearing when
 611          *       numa support is not compiled in, and later node_set_state
 612          *       will not set it back.
 613          */
 614         node_clear_state(0, N_MEMORY);
 615         if (N_MEMORY != N_NORMAL_MEMORY)
 616                 node_clear_state(0, N_NORMAL_MEMORY);
 617
 618         zone_sizes_init();
 619 }
 620
 621 /*
 622  * Memory hotplug specific functions
 623  */
 624 #ifdef CONFIG_MEMORY_HOTPLUG
 625 /*
 626  * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
 627  * updating.
 628  */
 629 static void  update_end_of_memory_vars(u64 start, u64 size)
 630 {
 631         unsigned long end_pfn = PFN_UP(start + size);
 632
 633         if (end_pfn > max_pfn) {
 634                 max_pfn = end_pfn;
 635                 max_low_pfn = end_pfn;
 636                 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 637         }
 638 }
 639
 640 /*
 641  * Memory is added always to NORMAL zone. This means you will never get
 642  * additional DMA/DMA32 memory.
 643  */
 644 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
 645 {
 646         struct pglist_data *pgdat = NODE_DATA(nid);
 647         struct zone *zone = pgdat->node_zones +
 648                 zone_for_memory(nid, start, size, ZONE_NORMAL, for_device);
 649         unsigned long start_pfn = start >> PAGE_SHIFT;
 650         unsigned long nr_pages = size >> PAGE_SHIFT;
 651         int ret;
 652
 653         init_memory_mapping(start, start + size);
 654
 655         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 656         WARN_ON_ONCE(ret);
 657
 658         /* update max_pfn, max_low_pfn and high_memory */
 659         update_end_of_memory_vars(start, size);
 660
 661         return ret;
 662 }
 663 EXPORT_SYMBOL_GPL(arch_add_memory);
 664
 665 #define PAGE_INUSE 0xFD
 666
 667 static void __meminit free_pagetable(struct page *page, int order)
 668 {
 669         unsigned long magic;
 670         unsigned int nr_pages = 1 << order;
 671         struct vmem_altmap *altmap = to_vmem_altmap((unsigned long) page);
 672
 673         if (altmap) {
 674                 vmem_altmap_free(altmap, nr_pages);
 675                 return;
 676         }
 677
 678         /* bootmem page has reserved flag */
 679         if (PageReserved(page)) {
 680                 __ClearPageReserved(page);
 681
 682                 magic = (unsigned long)page->lru.next;
 683                 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
 684                         while (nr_pages--)
 685                                 put_page_bootmem(page++);
 686                 } else
 687                         while (nr_pages--)
 688                                 free_reserved_page(page++);
 689         } else
 690                 free_pages((unsigned long)page_address(page), order);
 691 }
 692
 693 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
 694 {
 695         pte_t *pte;
 696         int i;
 697
 698         for (i = 0; i < PTRS_PER_PTE; i++) {
 699                 pte = pte_start + i;
 700                 if (!pte_none(*pte))
 701                         return;
 702         }
 703
 704         /* free a pte talbe */
 705         free_pagetable(pmd_page(*pmd), 0);
 706         spin_lock(&init_mm.page_table_lock);
 707         pmd_clear(pmd);
 708         spin_unlock(&init_mm.page_table_lock);
 709 }
 710
 711 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
 712 {
 713         pmd_t *pmd;
 714         int i;
 715
 716         for (i = 0; i < PTRS_PER_PMD; i++) {
 717                 pmd = pmd_start + i;
 718                 if (!pmd_none(*pmd))
 719                         return;
 720         }
 721
 722         /* free a pmd talbe */
 723         free_pagetable(pud_page(*pud), 0);
 724         spin_lock(&init_mm.page_table_lock);
 725         pud_clear(pud);
 726         spin_unlock(&init_mm.page_table_lock);
 727 }
 728
 729 static void __meminit
 730 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
 731                  bool direct)
 732 {
 733         unsigned long next, pages = 0;
 734         pte_t *pte;
 735         void *page_addr;
 736         phys_addr_t phys_addr;
 737
 738         pte = pte_start + pte_index(addr);
 739         for (; addr < end; addr = next, pte++) {
 740                 next = (addr + PAGE_SIZE) & PAGE_MASK;
 741                 if (next > end)
 742                         next = end;
 743
 744                 if (!pte_present(*pte))
 745                         continue;
 746
 747                 /*
 748                  * We mapped [0,1G) memory as identity mapping when
 749                  * initializing, in arch/x86/kernel/head_64.S. These
 750                  * pagetables cannot be removed.
 751                  */
 752                 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
 753                 if (phys_addr < (phys_addr_t)0x40000000)
 754                         return;
 755
 756                 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) {
 757                         /*
 758                          * Do not free direct mapping pages since they were
 759                          * freed when offlining, or simplely not in use.
 760                          */
 761                         if (!direct)
 762                                 free_pagetable(pte_page(*pte), 0);
 763
 764                         spin_lock(&init_mm.page_table_lock);
 765                         pte_clear(&init_mm, addr, pte);
 766                         spin_unlock(&init_mm.page_table_lock);
 767
 768                         /* For non-direct mapping, pages means nothing. */
 769                         pages++;
 770                 } else {
 771                         /*
 772                          * If we are here, we are freeing vmemmap pages since
 773                          * direct mapped memory ranges to be freed are aligned.
 774                          *
 775                          * If we are not removing the whole page, it means
 776                          * other page structs in this page are being used and
 777                          * we canot remove them. So fill the unused page_structs
 778                          * with 0xFD, and remove the page when it is wholly
 779                          * filled with 0xFD.
 780                          */
 781                         memset((void *)addr, PAGE_INUSE, next - addr);
 782
 783                         page_addr = page_address(pte_page(*pte));
 784                         if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
 785                                 free_pagetable(pte_page(*pte), 0);
 786
 787                                 spin_lock(&init_mm.page_table_lock);
 788                                 pte_clear(&init_mm, addr, pte);
 789                                 spin_unlock(&init_mm.page_table_lock);
 790                         }
 791                 }
 792         }
 793
 794         /* Call free_pte_table() in remove_pmd_table(). */
 795         flush_tlb_all();
 796         if (direct)
 797                 update_page_count(PG_LEVEL_4K, -pages);
 798 }
 799
 800 static void __meminit
 801 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 802                  bool direct)
 803 {
 804         unsigned long next, pages = 0;
 805         pte_t *pte_base;
 806         pmd_t *pmd;
 807         void *page_addr;
 808
 809         pmd = pmd_start + pmd_index(addr);
 810         for (; addr < end; addr = next, pmd++) {
 811                 next = pmd_addr_end(addr, end);
 812
 813                 if (!pmd_present(*pmd))
 814                         continue;
 815
 816                 if (pmd_large(*pmd)) {
 817                         if (IS_ALIGNED(addr, PMD_SIZE) &&
 818                             IS_ALIGNED(next, PMD_SIZE)) {
 819                                 if (!direct)
 820                                         free_pagetable(pmd_page(*pmd),
 821                                                        get_order(PMD_SIZE));
 822
 823                                 spin_lock(&init_mm.page_table_lock);
 824                                 pmd_clear(pmd);
 825                                 spin_unlock(&init_mm.page_table_lock);
 826                                 pages++;
 827                         } else {
 828                                 /* If here, we are freeing vmemmap pages. */
 829                                 memset((void *)addr, PAGE_INUSE, next - addr);
 830
 831                                 page_addr = page_address(pmd_page(*pmd));
 832                                 if (!memchr_inv(page_addr, PAGE_INUSE,
 833                                                 PMD_SIZE)) {
 834                                         free_pagetable(pmd_page(*pmd),
 835                                                        get_order(PMD_SIZE));
 836
 837                                         spin_lock(&init_mm.page_table_lock);
 838                                         pmd_clear(pmd);
 839                                         spin_unlock(&init_mm.page_table_lock);
 840                                 }
 841                         }
 842
 843                         continue;
 844                 }
 845
 846                 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
 847                 remove_pte_table(pte_base, addr, next, direct);
 848                 free_pte_table(pte_base, pmd);
 849         }
 850
 851         /* Call free_pmd_table() in remove_pud_table(). */
 852         if (direct)
 853                 update_page_count(PG_LEVEL_2M, -pages);
 854 }
 855
 856 static void __meminit
 857 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 858                  bool direct)
 859 {
 860         unsigned long next, pages = 0;
 861         pmd_t *pmd_base;
 862         pud_t *pud;
 863         void *page_addr;
 864
 865         pud = pud_start + pud_index(addr);
 866         for (; addr < end; addr = next, pud++) {
 867                 next = pud_addr_end(addr, end);
 868
 869                 if (!pud_present(*pud))
 870                         continue;
 871
 872                 if (pud_large(*pud)) {
 873                         if (IS_ALIGNED(addr, PUD_SIZE) &&
 874                             IS_ALIGNED(next, PUD_SIZE)) {
 875                                 if (!direct)
 876                                         free_pagetable(pud_page(*pud),
 877                                                        get_order(PUD_SIZE));
 878
 879                                 spin_lock(&init_mm.page_table_lock);
 880                                 pud_clear(pud);
 881                                 spin_unlock(&init_mm.page_table_lock);
 882                                 pages++;
 883                         } else {
 884                                 /* If here, we are freeing vmemmap pages. */
 885                                 memset((void *)addr, PAGE_INUSE, next - addr);
 886
 887                                 page_addr = page_address(pud_page(*pud));
 888                                 if (!memchr_inv(page_addr, PAGE_INUSE,
 889                                                 PUD_SIZE)) {
 890                                         free_pagetable(pud_page(*pud),
 891                                                        get_order(PUD_SIZE));
 892
 893                                         spin_lock(&init_mm.page_table_lock);
 894                                         pud_clear(pud);
 895                                         spin_unlock(&init_mm.page_table_lock);
 896                                 }
 897                         }
 898
 899                         continue;
 900                 }
 901
 902                 pmd_base = (pmd_t *)pud_page_vaddr(*pud);
 903                 remove_pmd_table(pmd_base, addr, next, direct);
 904                 free_pmd_table(pmd_base, pud);
 905         }
 906
 907         if (direct)
 908                 update_page_count(PG_LEVEL_1G, -pages);
 909 }
 910
 911 /* start and end are both virtual address. */
 912 static void __meminit
 913 remove_pagetable(unsigned long start, unsigned long end, bool direct)
 914 {
 915         unsigned long next;
 916         unsigned long addr;
 917         pgd_t *pgd;
 918         pud_t *pud;
 919
 920         for (addr = start; addr < end; addr = next) {
 921                 next = pgd_addr_end(addr, end);
 922
 923                 pgd = pgd_offset_k(addr);
 924                 if (!pgd_present(*pgd))
 925                         continue;
 926
 927                 pud = (pud_t *)pgd_page_vaddr(*pgd);
 928                 remove_pud_table(pud, addr, next, direct);
 929         }
 930
 931         flush_tlb_all();
 932 }
 933
 934 void __ref vmemmap_free(unsigned long start, unsigned long end)
 935 {
 936         remove_pagetable(start, end, false);
 937 }
 938
 939 #ifdef CONFIG_MEMORY_HOTREMOVE
 940 static void __meminit
 941 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
 942 {
 943         start = (unsigned long)__va(start);
 944         end = (unsigned long)__va(end);
 945
 946         remove_pagetable(start, end, true);
 947 }
 948
 949 int __ref arch_remove_memory(u64 start, u64 size)
 950 {
 951         unsigned long start_pfn = start >> PAGE_SHIFT;
 952         unsigned long nr_pages = size >> PAGE_SHIFT;
 953         struct page *page = pfn_to_page(start_pfn);
 954         struct vmem_altmap *altmap;
 955         struct zone *zone;
 956         int ret;
 957
 958         /* With altmap the first mapped page is offset from @start */
 959         altmap = to_vmem_altmap((unsigned long) page);
 960         if (altmap)
 961                 page += vmem_altmap_offset(altmap);
 962         zone = page_zone(page);
 963         ret = __remove_pages(zone, start_pfn, nr_pages);
 964         WARN_ON_ONCE(ret);
 965         kernel_physical_mapping_remove(start, start + size);
 966
 967         return ret;
 968 }
 969 #endif
 970 #endif /* CONFIG_MEMORY_HOTPLUG */
 971
 972 static struct kcore_list kcore_vsyscall;
 973
 974 static void __init register_page_bootmem_info(void)
 975 {
 976 #ifdef CONFIG_NUMA
 977         int i;
 978
 979         for_each_online_node(i)
 980                 register_page_bootmem_info_node(NODE_DATA(i));
 981 #endif
 982 }
 983
 984 void __init mem_init(void)
 985 {
 986         pci_iommu_alloc();
 987
 988         /* clear_bss() already clear the empty_zero_page */
 989
 990         register_page_bootmem_info();
 991
 992         /* this will put all memory onto the freelists */
 993         free_all_bootmem();
 994         after_bootmem = 1;
 995
 996         /* Register memory areas for /proc/kcore */
 997         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR,
 998                          PAGE_SIZE, KCORE_OTHER);
 999
1000         mem_init_print_info(NULL);
1001 }
1002
1003 const int rodata_test_data = 0xC3;
1004 EXPORT_SYMBOL_GPL(rodata_test_data);
1005
1006 int kernel_set_to_readonly;
1007
1008 void set_kernel_text_rw(void)
1009 {
1010         unsigned long start = PFN_ALIGN(_text);
1011         unsigned long end = PFN_ALIGN(__stop___ex_table);
1012
1013         if (!kernel_set_to_readonly)
1014                 return;
1015
1016         pr_debug("Set kernel text: %lx - %lx for read write\n",
1017                  start, end);
1018
1019         /*
1020          * Make the kernel identity mapping for text RW. Kernel text
1021          * mapping will always be RO. Refer to the comment in
1022          * static_protections() in pageattr.c
1023          */
1024         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1025 }
1026
1027 void set_kernel_text_ro(void)
1028 {
1029         unsigned long start = PFN_ALIGN(_text);
1030         unsigned long end = PFN_ALIGN(__stop___ex_table);
1031
1032         if (!kernel_set_to_readonly)
1033                 return;
1034
1035         pr_debug("Set kernel text: %lx - %lx for read only\n",
1036                  start, end);
1037
1038         /*
1039          * Set the kernel identity mapping for text RO.
1040          */
1041         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1042 }
1043
1044 void mark_rodata_ro(void)
1045 {
1046         unsigned long start = PFN_ALIGN(_text);
1047         unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1048         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1049         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1050         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1051         unsigned long all_end;
1052
1053         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1054                (end - start) >> 10);
1055         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1056
1057         kernel_set_to_readonly = 1;
1058
1059         /*
1060          * The rodata/data/bss/brk section (but not the kernel text!)
1061          * should also be not-executable.
1062          *
1063          * We align all_end to PMD_SIZE because the existing mapping
1064          * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1065          * split the PMD and the reminder between _brk_end and the end
1066          * of the PMD will remain mapped executable.
1067          *
1068          * Any PMD which was setup after the one which covers _brk_end
1069          * has been zapped already via cleanup_highmem().
1070          */
1071         all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1072         set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1073
1074         rodata_test();
1075
1076 #ifdef CONFIG_CPA_DEBUG
1077         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1078         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1079
1080         printk(KERN_INFO "Testing CPA: again\n");
1081         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1082 #endif
1083
1084         free_init_pages("unused kernel",
1085                         (unsigned long) __va(__pa_symbol(text_end)),
1086                         (unsigned long) __va(__pa_symbol(rodata_start)));
1087         free_init_pages("unused kernel",
1088                         (unsigned long) __va(__pa_symbol(rodata_end)),
1089                         (unsigned long) __va(__pa_symbol(_sdata)));
1090
1091         debug_checkwx();
1092 }
1093
1094 int kern_addr_valid(unsigned long addr)
1095 {
1096         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1097         pgd_t *pgd;
1098         pud_t *pud;
1099         pmd_t *pmd;
1100         pte_t *pte;
1101
1102         if (above != 0 && above != -1UL)
1103                 return 0;
1104
1105         pgd = pgd_offset_k(addr);
1106         if (pgd_none(*pgd))
1107                 return 0;
1108
1109         pud = pud_offset(pgd, addr);
1110         if (pud_none(*pud))
1111                 return 0;
1112
1113         if (pud_large(*pud))
1114                 return pfn_valid(pud_pfn(*pud));
1115
1116         pmd = pmd_offset(pud, addr);
1117         if (pmd_none(*pmd))
1118                 return 0;
1119
1120         if (pmd_large(*pmd))
1121                 return pfn_valid(pmd_pfn(*pmd));
1122
1123         pte = pte_offset_kernel(pmd, addr);
1124         if (pte_none(*pte))
1125                 return 0;
1126
1127         return pfn_valid(pte_pfn(*pte));
1128 }
1129
1130 static unsigned long probe_memory_block_size(void)
1131 {
1132         unsigned long bz = MIN_MEMORY_BLOCK_SIZE;
1133
1134         /* if system is UV or has 64GB of RAM or more, use large blocks */
1135         if (is_uv_system() || ((max_pfn << PAGE_SHIFT) >= (64UL << 30)))
1136                 bz = 2UL << 30; /* 2GB */
1137
1138         pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1139
1140         return bz;
1141 }
1142
1143 static unsigned long memory_block_size_probed;
1144 unsigned long memory_block_size_bytes(void)
1145 {
1146         if (!memory_block_size_probed)
1147                 memory_block_size_probed = probe_memory_block_size();
1148
1149         return memory_block_size_probed;
1150 }
1151
1152 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1153 /*
1154  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1155  */
1156 static long __meminitdata addr_start, addr_end;
1157 static void __meminitdata *p_start, *p_end;
1158 static int __meminitdata node_start;
1159
1160 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1161                 unsigned long end, int node, struct vmem_altmap *altmap)
1162 {
1163         unsigned long addr;
1164         unsigned long next;
1165         pgd_t *pgd;
1166         pud_t *pud;
1167         pmd_t *pmd;
1168
1169         for (addr = start; addr < end; addr = next) {
1170                 next = pmd_addr_end(addr, end);
1171
1172                 pgd = vmemmap_pgd_populate(addr, node);
1173                 if (!pgd)
1174                         return -ENOMEM;
1175
1176                 pud = vmemmap_pud_populate(pgd, addr, node);
1177                 if (!pud)
1178                         return -ENOMEM;
1179
1180                 pmd = pmd_offset(pud, addr);
1181                 if (pmd_none(*pmd)) {
1182                         void *p;
1183
1184                         p = __vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
1185                         if (p) {
1186                                 pte_t entry;
1187
1188                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1189                                                 PAGE_KERNEL_LARGE);
1190                                 set_pmd(pmd, __pmd(pte_val(entry)));
1191
1192                                 /* check to see if we have contiguous blocks */
1193                                 if (p_end != p || node_start != node) {
1194                                         if (p_start)
1195                                                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1196                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1197                                         addr_start = addr;
1198                                         node_start = node;
1199                                         p_start = p;
1200                                 }
1201
1202                                 addr_end = addr + PMD_SIZE;
1203                                 p_end = p + PMD_SIZE;
1204                                 continue;
1205                         } else if (altmap)
1206                                 return -ENOMEM; /* no fallback */
1207                 } else if (pmd_large(*pmd)) {
1208                         vmemmap_verify((pte_t *)pmd, node, addr, next);
1209                         continue;
1210                 }
1211                 pr_warn_once("vmemmap: falling back to regular page backing\n");
1212                 if (vmemmap_populate_basepages(addr, next, node))
1213                         return -ENOMEM;
1214         }
1215         return 0;
1216 }
1217
1218 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1219 {
1220         struct vmem_altmap *altmap = to_vmem_altmap(start);
1221         int err;
1222
1223         if (boot_cpu_has(X86_FEATURE_PSE))
1224                 err = vmemmap_populate_hugepages(start, end, node, altmap);
1225         else if (altmap) {
1226                 pr_err_once("%s: no cpu support for altmap allocations\n",
1227                                 __func__);
1228                 err = -ENOMEM;
1229         } else
1230                 err = vmemmap_populate_basepages(start, end, node);
1231         if (!err)
1232                 sync_global_pgds(start, end - 1);
1233         return err;
1234 }
1235
1236 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1237 void register_page_bootmem_memmap(unsigned long section_nr,
1238                                   struct page *start_page, unsigned long size)
1239 {
1240         unsigned long addr = (unsigned long)start_page;
1241         unsigned long end = (unsigned long)(start_page + size);
1242         unsigned long next;
1243         pgd_t *pgd;
1244         pud_t *pud;
1245         pmd_t *pmd;
1246         unsigned int nr_pages;
1247         struct page *page;
1248
1249         for (; addr < end; addr = next) {
1250                 pte_t *pte = NULL;
1251
1252                 pgd = pgd_offset_k(addr);
1253                 if (pgd_none(*pgd)) {
1254                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1255                         continue;
1256                 }
1257                 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1258
1259                 pud = pud_offset(pgd, addr);
1260                 if (pud_none(*pud)) {
1261                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1262                         continue;
1263                 }
1264                 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1265
1266                 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1267                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1268                         pmd = pmd_offset(pud, addr);
1269                         if (pmd_none(*pmd))
1270                                 continue;
1271                         get_page_bootmem(section_nr, pmd_page(*pmd),
1272                                          MIX_SECTION_INFO);
1273
1274                         pte = pte_offset_kernel(pmd, addr);
1275                         if (pte_none(*pte))
1276                                 continue;
1277                         get_page_bootmem(section_nr, pte_page(*pte),
1278                                          SECTION_INFO);
1279                 } else {
1280                         next = pmd_addr_end(addr, end);
1281
1282                         pmd = pmd_offset(pud, addr);
1283                         if (pmd_none(*pmd))
1284                                 continue;
1285
1286                         nr_pages = 1 << (get_order(PMD_SIZE));
1287                         page = pmd_page(*pmd);
1288                         while (nr_pages--)
1289                                 get_page_bootmem(section_nr, page++,
1290                                                  SECTION_INFO);
1291                 }
1292         }
1293 }
1294 #endif
1295
1296 void __meminit vmemmap_populate_print_last(void)
1297 {
1298         if (p_start) {
1299                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1300                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1301                 p_start = NULL;
1302                 p_end = NULL;
1303                 node_start = 0;
1304         }
1305 }
1306 #endif