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 <asm/uaccess.h>
  40 #include <asm/pgtable.h>
  41 #include <asm/pgalloc.h>
  42 #include <asm/dma.h>
  43 #include <asm/fixmap.h>
  44 #include <asm/e820.h>
  45 #include <asm/apic.h>
  46 #include <asm/tlb.h>
  47 #include <asm/mmu_context.h>
  48 #include <asm/proto.h>
  49 #include <asm/smp.h>
  50 #include <asm/sections.h>
  51 #include <asm/kdebug.h>
  52 #include <asm/numa.h>
  53 #include <asm/cacheflush.h>
  54 #include <asm/init.h>
  55 #include <asm/uv/uv.h>
  56 #include <asm/setup.h>
  57
  58 #include "mm_internal.h"
  59
  60 #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/removed 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, int removed)
  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                 /*
 104                  * When it is called after memory hot remove, pgd_none()
 105                  * returns true. In this case (removed == 1), we must clear
 106                  * the PGD entries in the local PGD level page.
 107                  */
 108                 if (pgd_none(*pgd_ref) && !removed)
 109                         continue;
 110
 111                 spin_lock(&pgd_lock);
 112                 list_for_each_entry(page, &pgd_list, lru) {
 113                         pgd_t *pgd;
 114                         spinlock_t *pgt_lock;
 115
 116                         pgd = (pgd_t *)page_address(page) + pgd_index(address);
 117                         /* the pgt_lock only for Xen */
 118                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
 119                         spin_lock(pgt_lock);
 120
 121                         if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
 122                                 BUG_ON(pgd_page_vaddr(*pgd)
 123                                        != pgd_page_vaddr(*pgd_ref));
 124
 125                         if (removed) {
 126                                 if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
 127                                         pgd_clear(pgd);
 128                         } else {
 129                                 if (pgd_none(*pgd))
 130                                         set_pgd(pgd, *pgd_ref);
 131                         }
 132
 133                         spin_unlock(pgt_lock);
 134                 }
 135                 spin_unlock(&pgd_lock);
 136         }
 137 }
 138
 139 /*
 140  * NOTE: This function is marked __ref because it calls __init function
 141  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
 142  */
 143 static __ref void *spp_getpage(void)
 144 {
 145         void *ptr;
 146
 147         if (after_bootmem)
 148                 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
 149         else
 150                 ptr = alloc_bootmem_pages(PAGE_SIZE);
 151
 152         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
 153                 panic("set_pte_phys: cannot allocate page data %s\n",
 154                         after_bootmem ? "after bootmem" : "");
 155         }
 156
 157         pr_debug("spp_getpage %p\n", ptr);
 158
 159         return ptr;
 160 }
 161
 162 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
 163 {
 164         if (pgd_none(*pgd)) {
 165                 pud_t *pud = (pud_t *)spp_getpage();
 166                 pgd_populate(&init_mm, pgd, pud);
 167                 if (pud != pud_offset(pgd, 0))
 168                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
 169                                pud, pud_offset(pgd, 0));
 170         }
 171         return pud_offset(pgd, vaddr);
 172 }
 173
 174 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
 175 {
 176         if (pud_none(*pud)) {
 177                 pmd_t *pmd = (pmd_t *) spp_getpage();
 178                 pud_populate(&init_mm, pud, pmd);
 179                 if (pmd != pmd_offset(pud, 0))
 180                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
 181                                pmd, pmd_offset(pud, 0));
 182         }
 183         return pmd_offset(pud, vaddr);
 184 }
 185
 186 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
 187 {
 188         if (pmd_none(*pmd)) {
 189                 pte_t *pte = (pte_t *) spp_getpage();
 190                 pmd_populate_kernel(&init_mm, pmd, pte);
 191                 if (pte != pte_offset_kernel(pmd, 0))
 192                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
 193         }
 194         return pte_offset_kernel(pmd, vaddr);
 195 }
 196
 197 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
 198 {
 199         pud_t *pud;
 200         pmd_t *pmd;
 201         pte_t *pte;
 202
 203         pud = pud_page + pud_index(vaddr);
 204         pmd = fill_pmd(pud, vaddr);
 205         pte = fill_pte(pmd, vaddr);
 206
 207         set_pte(pte, new_pte);
 208
 209         /*
 210          * It's enough to flush this one mapping.
 211          * (PGE mappings get flushed as well)
 212          */
 213         __flush_tlb_one(vaddr);
 214 }
 215
 216 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
 217 {
 218         pgd_t *pgd;
 219         pud_t *pud_page;
 220
 221         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
 222
 223         pgd = pgd_offset_k(vaddr);
 224         if (pgd_none(*pgd)) {
 225                 printk(KERN_ERR
 226                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
 227                 return;
 228         }
 229         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
 230         set_pte_vaddr_pud(pud_page, vaddr, pteval);
 231 }
 232
 233 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
 234 {
 235         pgd_t *pgd;
 236         pud_t *pud;
 237
 238         pgd = pgd_offset_k(vaddr);
 239         pud = fill_pud(pgd, vaddr);
 240         return fill_pmd(pud, vaddr);
 241 }
 242
 243 pte_t * __init populate_extra_pte(unsigned long vaddr)
 244 {
 245         pmd_t *pmd;
 246
 247         pmd = populate_extra_pmd(vaddr);
 248         return fill_pte(pmd, vaddr);
 249 }
 250
 251 /*
 252  * Create large page table mappings for a range of physical addresses.
 253  */
 254 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
 255                                         enum page_cache_mode cache)
 256 {
 257         pgd_t *pgd;
 258         pud_t *pud;
 259         pmd_t *pmd;
 260         pgprot_t prot;
 261
 262         pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
 263                 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
 264         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
 265         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
 266                 pgd = pgd_offset_k((unsigned long)__va(phys));
 267                 if (pgd_none(*pgd)) {
 268                         pud = (pud_t *) spp_getpage();
 269                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
 270                                                 _PAGE_USER));
 271                 }
 272                 pud = pud_offset(pgd, (unsigned long)__va(phys));
 273                 if (pud_none(*pud)) {
 274                         pmd = (pmd_t *) spp_getpage();
 275                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
 276                                                 _PAGE_USER));
 277                 }
 278                 pmd = pmd_offset(pud, phys);
 279                 BUG_ON(!pmd_none(*pmd));
 280                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
 281         }
 282 }
 283
 284 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
 285 {
 286         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
 287 }
 288
 289 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 290 {
 291         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
 292 }
 293
 294 /*
 295  * The head.S code sets up the kernel high mapping:
 296  *
 297  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
 298  *
 299  * phys_base holds the negative offset to the kernel, which is added
 300  * to the compile time generated pmds. This results in invalid pmds up
 301  * to the point where we hit the physaddr 0 mapping.
 302  *
 303  * We limit the mappings to the region from _text to _brk_end.  _brk_end
 304  * is rounded up to the 2MB boundary. This catches the invalid pmds as
 305  * well, as they are located before _text:
 306  */
 307 void __init cleanup_highmap(void)
 308 {
 309         unsigned long vaddr = __START_KERNEL_map;
 310         unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
 311         unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
 312         pmd_t *pmd = level2_kernel_pgt;
 313
 314         /*
 315          * Native path, max_pfn_mapped is not set yet.
 316          * Xen has valid max_pfn_mapped set in
 317          *      arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
 318          */
 319         if (max_pfn_mapped)
 320                 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
 321
 322         for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
 323                 if (pmd_none(*pmd))
 324                         continue;
 325                 if (vaddr < (unsigned long) _text || vaddr > end)
 326                         set_pmd(pmd, __pmd(0));
 327         }
 328 }
 329
 330 /*
 331  * Create PTE level page table mapping for physical addresses.
 332  * It returns the last physical address mapped.
 333  */
 334 static unsigned long __meminit
 335 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
 336               pgprot_t prot)
 337 {
 338         unsigned long pages = 0, paddr_next;
 339         unsigned long paddr_last = paddr_end;
 340         pte_t *pte;
 341         int i;
 342
 343         pte = pte_page + pte_index(paddr);
 344         i = pte_index(paddr);
 345
 346         for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
 347                 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
 348                 if (paddr >= paddr_end) {
 349                         if (!after_bootmem &&
 350                             !e820_any_mapped(paddr & PAGE_MASK, paddr_next,
 351                                              E820_RAM) &&
 352                             !e820_any_mapped(paddr & PAGE_MASK, paddr_next,
 353                                              E820_RESERVED_KERN))
 354                                 set_pte(pte, __pte(0));
 355                         continue;
 356                 }
 357
 358                 /*
 359                  * We will re-use the existing mapping.
 360                  * Xen for example has some special requirements, like mapping
 361                  * pagetable pages as RO. So assume someone who pre-setup
 362                  * these mappings are more intelligent.
 363                  */
 364                 if (!pte_none(*pte)) {
 365                         if (!after_bootmem)
 366                                 pages++;
 367                         continue;
 368                 }
 369
 370                 if (0)
 371                         pr_info("   pte=%p addr=%lx pte=%016lx\n", pte, paddr,
 372                                 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
 373                 pages++;
 374                 set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));
 375                 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
 376         }
 377
 378         update_page_count(PG_LEVEL_4K, pages);
 379
 380         return paddr_last;
 381 }
 382
 383 /*
 384  * Create PMD level page table mapping for physical addresses. The virtual
 385  * and physical address have to be aligned at this level.
 386  * It returns the last physical address mapped.
 387  */
 388 static unsigned long __meminit
 389 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
 390               unsigned long page_size_mask, pgprot_t prot)
 391 {
 392         unsigned long pages = 0, paddr_next;
 393         unsigned long paddr_last = paddr_end;
 394
 395         int i = pmd_index(paddr);
 396
 397         for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
 398                 pmd_t *pmd = pmd_page + pmd_index(paddr);
 399                 pte_t *pte;
 400                 pgprot_t new_prot = prot;
 401
 402                 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
 403                 if (paddr >= paddr_end) {
 404                         if (!after_bootmem &&
 405                             !e820_any_mapped(paddr & PMD_MASK, paddr_next,
 406                                              E820_RAM) &&
 407                             !e820_any_mapped(paddr & PMD_MASK, paddr_next,
 408                                              E820_RESERVED_KERN))
 409                                 set_pmd(pmd, __pmd(0));
 410                         continue;
 411                 }
 412
 413                 if (!pmd_none(*pmd)) {
 414                         if (!pmd_large(*pmd)) {
 415                                 spin_lock(&init_mm.page_table_lock);
 416                                 pte = (pte_t *)pmd_page_vaddr(*pmd);
 417                                 paddr_last = phys_pte_init(pte, paddr,
 418                                                            paddr_end, prot);
 419                                 spin_unlock(&init_mm.page_table_lock);
 420                                 continue;
 421                         }
 422                         /*
 423                          * If we are ok with PG_LEVEL_2M mapping, then we will
 424                          * use the existing mapping,
 425                          *
 426                          * Otherwise, we will split the large page mapping but
 427                          * use the same existing protection bits except for
 428                          * large page, so that we don't violate Intel's TLB
 429                          * Application note (317080) which says, while changing
 430                          * the page sizes, new and old translations should
 431                          * not differ with respect to page frame and
 432                          * attributes.
 433                          */
 434                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
 435                                 if (!after_bootmem)
 436                                         pages++;
 437                                 paddr_last = paddr_next;
 438                                 continue;
 439                         }
 440                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
 441                 }
 442
 443                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
 444                         pages++;
 445                         spin_lock(&init_mm.page_table_lock);
 446                         set_pte((pte_t *)pmd,
 447                                 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
 448                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
 449                         spin_unlock(&init_mm.page_table_lock);
 450                         paddr_last = paddr_next;
 451                         continue;
 452                 }
 453
 454                 pte = alloc_low_page();
 455                 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot);
 456
 457                 spin_lock(&init_mm.page_table_lock);
 458                 pmd_populate_kernel(&init_mm, pmd, pte);
 459                 spin_unlock(&init_mm.page_table_lock);
 460         }
 461         update_page_count(PG_LEVEL_2M, pages);
 462         return paddr_last;
 463 }
 464
 465 /*
 466  * Create PUD level page table mapping for physical addresses. The virtual
 467  * and physical address do not have to be aligned at this level. KASLR can
 468  * randomize virtual addresses up to this level.
 469  * It returns the last physical address mapped.
 470  */
 471 static unsigned long __meminit
 472 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
 473               unsigned long page_size_mask)
 474 {
 475         unsigned long pages = 0, paddr_next;
 476         unsigned long paddr_last = paddr_end;
 477         unsigned long vaddr = (unsigned long)__va(paddr);
 478         int i = pud_index(vaddr);
 479
 480         for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
 481                 pud_t *pud;
 482                 pmd_t *pmd;
 483                 pgprot_t prot = PAGE_KERNEL;
 484
 485                 vaddr = (unsigned long)__va(paddr);
 486                 pud = pud_page + pud_index(vaddr);
 487                 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
 488
 489                 if (paddr >= paddr_end) {
 490                         if (!after_bootmem &&
 491                             !e820_any_mapped(paddr & PUD_MASK, paddr_next,
 492                                              E820_RAM) &&
 493                             !e820_any_mapped(paddr & PUD_MASK, paddr_next,
 494                                              E820_RESERVED_KERN))
 495                                 set_pud(pud, __pud(0));
 496                         continue;
 497                 }
 498
 499                 if (!pud_none(*pud)) {
 500                         if (!pud_large(*pud)) {
 501                                 pmd = pmd_offset(pud, 0);
 502                                 paddr_last = phys_pmd_init(pmd, paddr,
 503                                                            paddr_end,
 504                                                            page_size_mask,
 505                                                            prot);
 506                                 __flush_tlb_all();
 507                                 continue;
 508                         }
 509                         /*
 510                          * If we are ok with PG_LEVEL_1G mapping, then we will
 511                          * use the existing mapping.
 512                          *
 513                          * Otherwise, we will split the gbpage mapping but use
 514                          * the same existing protection  bits except for large
 515                          * page, so that we don't violate Intel's TLB
 516                          * Application note (317080) which says, while changing
 517                          * the page sizes, new and old translations should
 518                          * not differ with respect to page frame and
 519                          * attributes.
 520                          */
 521                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
 522                                 if (!after_bootmem)
 523                                         pages++;
 524                                 paddr_last = paddr_next;
 525                                 continue;
 526                         }
 527                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
 528                 }
 529
 530                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
 531                         pages++;
 532                         spin_lock(&init_mm.page_table_lock);
 533                         set_pte((pte_t *)pud,
 534                                 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
 535                                         PAGE_KERNEL_LARGE));
 536                         spin_unlock(&init_mm.page_table_lock);
 537                         paddr_last = paddr_next;
 538                         continue;
 539                 }
 540
 541                 pmd = alloc_low_page();
 542                 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
 543                                            page_size_mask, prot);
 544
 545                 spin_lock(&init_mm.page_table_lock);
 546                 pud_populate(&init_mm, pud, pmd);
 547                 spin_unlock(&init_mm.page_table_lock);
 548         }
 549         __flush_tlb_all();
 550
 551         update_page_count(PG_LEVEL_1G, pages);
 552
 553         return paddr_last;
 554 }
 555
 556 /*
 557  * Create page table mapping for the physical memory for specific physical
 558  * addresses. The virtual and physical addresses have to be aligned on PMD level
 559  * down. It returns the last physical address mapped.
 560  */
 561 unsigned long __meminit
 562 kernel_physical_mapping_init(unsigned long paddr_start,
 563                              unsigned long paddr_end,
 564                              unsigned long page_size_mask)
 565 {
 566         bool pgd_changed = false;
 567         unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
 568
 569         paddr_last = paddr_end;
 570         vaddr = (unsigned long)__va(paddr_start);
 571         vaddr_end = (unsigned long)__va(paddr_end);
 572         vaddr_start = vaddr;
 573
 574         for (; vaddr < vaddr_end; vaddr = vaddr_next) {
 575                 pgd_t *pgd = pgd_offset_k(vaddr);
 576                 pud_t *pud;
 577
 578                 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
 579
 580                 if (pgd_val(*pgd)) {
 581                         pud = (pud_t *)pgd_page_vaddr(*pgd);
 582                         paddr_last = phys_pud_init(pud, __pa(vaddr),
 583                                                    __pa(vaddr_end),
 584                                                    page_size_mask);
 585                         continue;
 586                 }
 587
 588                 pud = alloc_low_page();
 589                 paddr_last = phys_pud_init(pud, __pa(vaddr), __pa(vaddr_end),
 590                                            page_size_mask);
 591
 592                 spin_lock(&init_mm.page_table_lock);
 593                 pgd_populate(&init_mm, pgd, pud);
 594                 spin_unlock(&init_mm.page_table_lock);
 595                 pgd_changed = true;
 596         }
 597
 598         if (pgd_changed)
 599                 sync_global_pgds(vaddr_start, vaddr_end - 1, 0);
 600
 601         __flush_tlb_all();
 602
 603         return paddr_last;
 604 }
 605
 606 #ifndef CONFIG_NUMA
 607 void __init initmem_init(void)
 608 {
 609         memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
 610 }
 611 #endif
 612
 613 void __init paging_init(void)
 614 {
 615         sparse_memory_present_with_active_regions(MAX_NUMNODES);
 616         sparse_init();
 617
 618         /*
 619          * clear the default setting with node 0
 620          * note: don't use nodes_clear here, that is really clearing when
 621          *       numa support is not compiled in, and later node_set_state
 622          *       will not set it back.
 623          */
 624         node_clear_state(0, N_MEMORY);
 625         if (N_MEMORY != N_NORMAL_MEMORY)
 626                 node_clear_state(0, N_NORMAL_MEMORY);
 627
 628         zone_sizes_init();
 629 }
 630
 631 /*
 632  * Memory hotplug specific functions
 633  */
 634 #ifdef CONFIG_MEMORY_HOTPLUG
 635 /*
 636  * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
 637  * updating.
 638  */
 639 static void  update_end_of_memory_vars(u64 start, u64 size)
 640 {
 641         unsigned long end_pfn = PFN_UP(start + size);
 642
 643         if (end_pfn > max_pfn) {
 644                 max_pfn = end_pfn;
 645                 max_low_pfn = end_pfn;
 646                 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 647         }
 648 }
 649
 650 /*
 651  * Memory is added always to NORMAL zone. This means you will never get
 652  * additional DMA/DMA32 memory.
 653  */
 654 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
 655 {
 656         struct pglist_data *pgdat = NODE_DATA(nid);
 657         struct zone *zone = pgdat->node_zones +
 658                 zone_for_memory(nid, start, size, ZONE_NORMAL, for_device);
 659         unsigned long start_pfn = start >> PAGE_SHIFT;
 660         unsigned long nr_pages = size >> PAGE_SHIFT;
 661         int ret;
 662
 663         init_memory_mapping(start, start + size);
 664
 665         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 666         WARN_ON_ONCE(ret);
 667
 668         /* update max_pfn, max_low_pfn and high_memory */
 669         update_end_of_memory_vars(start, size);
 670
 671         return ret;
 672 }
 673 EXPORT_SYMBOL_GPL(arch_add_memory);
 674
 675 #define PAGE_INUSE 0xFD
 676
 677 static void __meminit free_pagetable(struct page *page, int order)
 678 {
 679         unsigned long magic;
 680         unsigned int nr_pages = 1 << order;
 681         struct vmem_altmap *altmap = to_vmem_altmap((unsigned long) page);
 682
 683         if (altmap) {
 684                 vmem_altmap_free(altmap, nr_pages);
 685                 return;
 686         }
 687
 688         /* bootmem page has reserved flag */
 689         if (PageReserved(page)) {
 690                 __ClearPageReserved(page);
 691
 692                 magic = (unsigned long)page->lru.next;
 693                 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
 694                         while (nr_pages--)
 695                                 put_page_bootmem(page++);
 696                 } else
 697                         while (nr_pages--)
 698                                 free_reserved_page(page++);
 699         } else
 700                 free_pages((unsigned long)page_address(page), order);
 701 }
 702
 703 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
 704 {
 705         pte_t *pte;
 706         int i;
 707
 708         for (i = 0; i < PTRS_PER_PTE; i++) {
 709                 pte = pte_start + i;
 710                 if (!pte_none(*pte))
 711                         return;
 712         }
 713
 714         /* free a pte talbe */
 715         free_pagetable(pmd_page(*pmd), 0);
 716         spin_lock(&init_mm.page_table_lock);
 717         pmd_clear(pmd);
 718         spin_unlock(&init_mm.page_table_lock);
 719 }
 720
 721 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
 722 {
 723         pmd_t *pmd;
 724         int i;
 725
 726         for (i = 0; i < PTRS_PER_PMD; i++) {
 727                 pmd = pmd_start + i;
 728                 if (!pmd_none(*pmd))
 729                         return;
 730         }
 731
 732         /* free a pmd talbe */
 733         free_pagetable(pud_page(*pud), 0);
 734         spin_lock(&init_mm.page_table_lock);
 735         pud_clear(pud);
 736         spin_unlock(&init_mm.page_table_lock);
 737 }
 738
 739 static void __meminit
 740 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
 741                  bool direct)
 742 {
 743         unsigned long next, pages = 0;
 744         pte_t *pte;
 745         void *page_addr;
 746         phys_addr_t phys_addr;
 747
 748         pte = pte_start + pte_index(addr);
 749         for (; addr < end; addr = next, pte++) {
 750                 next = (addr + PAGE_SIZE) & PAGE_MASK;
 751                 if (next > end)
 752                         next = end;
 753
 754                 if (!pte_present(*pte))
 755                         continue;
 756
 757                 /*
 758                  * We mapped [0,1G) memory as identity mapping when
 759                  * initializing, in arch/x86/kernel/head_64.S. These
 760                  * pagetables cannot be removed.
 761                  */
 762                 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
 763                 if (phys_addr < (phys_addr_t)0x40000000)
 764                         return;
 765
 766                 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) {
 767                         /*
 768                          * Do not free direct mapping pages since they were
 769                          * freed when offlining, or simplely not in use.
 770                          */
 771                         if (!direct)
 772                                 free_pagetable(pte_page(*pte), 0);
 773
 774                         spin_lock(&init_mm.page_table_lock);
 775                         pte_clear(&init_mm, addr, pte);
 776                         spin_unlock(&init_mm.page_table_lock);
 777
 778                         /* For non-direct mapping, pages means nothing. */
 779                         pages++;
 780                 } else {
 781                         /*
 782                          * If we are here, we are freeing vmemmap pages since
 783                          * direct mapped memory ranges to be freed are aligned.
 784                          *
 785                          * If we are not removing the whole page, it means
 786                          * other page structs in this page are being used and
 787                          * we canot remove them. So fill the unused page_structs
 788                          * with 0xFD, and remove the page when it is wholly
 789                          * filled with 0xFD.
 790                          */
 791                         memset((void *)addr, PAGE_INUSE, next - addr);
 792
 793                         page_addr = page_address(pte_page(*pte));
 794                         if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
 795                                 free_pagetable(pte_page(*pte), 0);
 796
 797                                 spin_lock(&init_mm.page_table_lock);
 798                                 pte_clear(&init_mm, addr, pte);
 799                                 spin_unlock(&init_mm.page_table_lock);
 800                         }
 801                 }
 802         }
 803
 804         /* Call free_pte_table() in remove_pmd_table(). */
 805         flush_tlb_all();
 806         if (direct)
 807                 update_page_count(PG_LEVEL_4K, -pages);
 808 }
 809
 810 static void __meminit
 811 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
 812                  bool direct)
 813 {
 814         unsigned long next, pages = 0;
 815         pte_t *pte_base;
 816         pmd_t *pmd;
 817         void *page_addr;
 818
 819         pmd = pmd_start + pmd_index(addr);
 820         for (; addr < end; addr = next, pmd++) {
 821                 next = pmd_addr_end(addr, end);
 822
 823                 if (!pmd_present(*pmd))
 824                         continue;
 825
 826                 if (pmd_large(*pmd)) {
 827                         if (IS_ALIGNED(addr, PMD_SIZE) &&
 828                             IS_ALIGNED(next, PMD_SIZE)) {
 829                                 if (!direct)
 830                                         free_pagetable(pmd_page(*pmd),
 831                                                        get_order(PMD_SIZE));
 832
 833                                 spin_lock(&init_mm.page_table_lock);
 834                                 pmd_clear(pmd);
 835                                 spin_unlock(&init_mm.page_table_lock);
 836                                 pages++;
 837                         } else {
 838                                 /* If here, we are freeing vmemmap pages. */
 839                                 memset((void *)addr, PAGE_INUSE, next - addr);
 840
 841                                 page_addr = page_address(pmd_page(*pmd));
 842                                 if (!memchr_inv(page_addr, PAGE_INUSE,
 843                                                 PMD_SIZE)) {
 844                                         free_pagetable(pmd_page(*pmd),
 845                                                        get_order(PMD_SIZE));
 846
 847                                         spin_lock(&init_mm.page_table_lock);
 848                                         pmd_clear(pmd);
 849                                         spin_unlock(&init_mm.page_table_lock);
 850                                 }
 851                         }
 852
 853                         continue;
 854                 }
 855
 856                 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
 857                 remove_pte_table(pte_base, addr, next, direct);
 858                 free_pte_table(pte_base, pmd);
 859         }
 860
 861         /* Call free_pmd_table() in remove_pud_table(). */
 862         if (direct)
 863                 update_page_count(PG_LEVEL_2M, -pages);
 864 }
 865
 866 static void __meminit
 867 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
 868                  bool direct)
 869 {
 870         unsigned long next, pages = 0;
 871         pmd_t *pmd_base;
 872         pud_t *pud;
 873         void *page_addr;
 874
 875         pud = pud_start + pud_index(addr);
 876         for (; addr < end; addr = next, pud++) {
 877                 next = pud_addr_end(addr, end);
 878
 879                 if (!pud_present(*pud))
 880                         continue;
 881
 882                 if (pud_large(*pud)) {
 883                         if (IS_ALIGNED(addr, PUD_SIZE) &&
 884                             IS_ALIGNED(next, PUD_SIZE)) {
 885                                 if (!direct)
 886                                         free_pagetable(pud_page(*pud),
 887                                                        get_order(PUD_SIZE));
 888
 889                                 spin_lock(&init_mm.page_table_lock);
 890                                 pud_clear(pud);
 891                                 spin_unlock(&init_mm.page_table_lock);
 892                                 pages++;
 893                         } else {
 894                                 /* If here, we are freeing vmemmap pages. */
 895                                 memset((void *)addr, PAGE_INUSE, next - addr);
 896
 897                                 page_addr = page_address(pud_page(*pud));
 898                                 if (!memchr_inv(page_addr, PAGE_INUSE,
 899                                                 PUD_SIZE)) {
 900                                         free_pagetable(pud_page(*pud),
 901                                                        get_order(PUD_SIZE));
 902
 903                                         spin_lock(&init_mm.page_table_lock);
 904                                         pud_clear(pud);
 905                                         spin_unlock(&init_mm.page_table_lock);
 906                                 }
 907                         }
 908
 909                         continue;
 910                 }
 911
 912                 pmd_base = (pmd_t *)pud_page_vaddr(*pud);
 913                 remove_pmd_table(pmd_base, addr, next, direct);
 914                 free_pmd_table(pmd_base, pud);
 915         }
 916
 917         if (direct)
 918                 update_page_count(PG_LEVEL_1G, -pages);
 919 }
 920
 921 /* start and end are both virtual address. */
 922 static void __meminit
 923 remove_pagetable(unsigned long start, unsigned long end, bool direct)
 924 {
 925         unsigned long next;
 926         unsigned long addr;
 927         pgd_t *pgd;
 928         pud_t *pud;
 929
 930         for (addr = start; addr < end; addr = next) {
 931                 next = pgd_addr_end(addr, end);
 932
 933                 pgd = pgd_offset_k(addr);
 934                 if (!pgd_present(*pgd))
 935                         continue;
 936
 937                 pud = (pud_t *)pgd_page_vaddr(*pgd);
 938                 remove_pud_table(pud, addr, next, direct);
 939         }
 940
 941         flush_tlb_all();
 942 }
 943
 944 void __ref vmemmap_free(unsigned long start, unsigned long end)
 945 {
 946         remove_pagetable(start, end, false);
 947 }
 948
 949 #ifdef CONFIG_MEMORY_HOTREMOVE
 950 static void __meminit
 951 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
 952 {
 953         start = (unsigned long)__va(start);
 954         end = (unsigned long)__va(end);
 955
 956         remove_pagetable(start, end, true);
 957 }
 958
 959 int __ref arch_remove_memory(u64 start, u64 size)
 960 {
 961         unsigned long start_pfn = start >> PAGE_SHIFT;
 962         unsigned long nr_pages = size >> PAGE_SHIFT;
 963         struct page *page = pfn_to_page(start_pfn);
 964         struct vmem_altmap *altmap;
 965         struct zone *zone;
 966         int ret;
 967
 968         /* With altmap the first mapped page is offset from @start */
 969         altmap = to_vmem_altmap((unsigned long) page);
 970         if (altmap)
 971                 page += vmem_altmap_offset(altmap);
 972         zone = page_zone(page);
 973         ret = __remove_pages(zone, start_pfn, nr_pages);
 974         WARN_ON_ONCE(ret);
 975         kernel_physical_mapping_remove(start, start + size);
 976
 977         return ret;
 978 }
 979 #endif
 980 #endif /* CONFIG_MEMORY_HOTPLUG */
 981
 982 static struct kcore_list kcore_vsyscall;
 983
 984 static void __init register_page_bootmem_info(void)
 985 {
 986 #ifdef CONFIG_NUMA
 987         int i;
 988
 989         for_each_online_node(i)
 990                 register_page_bootmem_info_node(NODE_DATA(i));
 991 #endif
 992 }
 993
 994 void __init mem_init(void)
 995 {
 996         pci_iommu_alloc();
 997
 998         /* clear_bss() already clear the empty_zero_page */
 999
1000         register_page_bootmem_info();
1001
1002         /* this will put all memory onto the freelists */
1003         free_all_bootmem();
1004         after_bootmem = 1;
1005
1006         /* Register memory areas for /proc/kcore */
1007         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR,
1008                          PAGE_SIZE, KCORE_OTHER);
1009
1010         mem_init_print_info(NULL);
1011 }
1012
1013 const int rodata_test_data = 0xC3;
1014 EXPORT_SYMBOL_GPL(rodata_test_data);
1015
1016 int kernel_set_to_readonly;
1017
1018 void set_kernel_text_rw(void)
1019 {
1020         unsigned long start = PFN_ALIGN(_text);
1021         unsigned long end = PFN_ALIGN(__stop___ex_table);
1022
1023         if (!kernel_set_to_readonly)
1024                 return;
1025
1026         pr_debug("Set kernel text: %lx - %lx for read write\n",
1027                  start, end);
1028
1029         /*
1030          * Make the kernel identity mapping for text RW. Kernel text
1031          * mapping will always be RO. Refer to the comment in
1032          * static_protections() in pageattr.c
1033          */
1034         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1035 }
1036
1037 void set_kernel_text_ro(void)
1038 {
1039         unsigned long start = PFN_ALIGN(_text);
1040         unsigned long end = PFN_ALIGN(__stop___ex_table);
1041
1042         if (!kernel_set_to_readonly)
1043                 return;
1044
1045         pr_debug("Set kernel text: %lx - %lx for read only\n",
1046                  start, end);
1047
1048         /*
1049          * Set the kernel identity mapping for text RO.
1050          */
1051         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1052 }
1053
1054 void mark_rodata_ro(void)
1055 {
1056         unsigned long start = PFN_ALIGN(_text);
1057         unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1058         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1059         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1060         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1061         unsigned long all_end;
1062
1063         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1064                (end - start) >> 10);
1065         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1066
1067         kernel_set_to_readonly = 1;
1068
1069         /*
1070          * The rodata/data/bss/brk section (but not the kernel text!)
1071          * should also be not-executable.
1072          *
1073          * We align all_end to PMD_SIZE because the existing mapping
1074          * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1075          * split the PMD and the reminder between _brk_end and the end
1076          * of the PMD will remain mapped executable.
1077          *
1078          * Any PMD which was setup after the one which covers _brk_end
1079          * has been zapped already via cleanup_highmem().
1080          */
1081         all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1082         set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1083
1084         rodata_test();
1085
1086 #ifdef CONFIG_CPA_DEBUG
1087         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1088         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1089
1090         printk(KERN_INFO "Testing CPA: again\n");
1091         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1092 #endif
1093
1094         free_init_pages("unused kernel",
1095                         (unsigned long) __va(__pa_symbol(text_end)),
1096                         (unsigned long) __va(__pa_symbol(rodata_start)));
1097         free_init_pages("unused kernel",
1098                         (unsigned long) __va(__pa_symbol(rodata_end)),
1099                         (unsigned long) __va(__pa_symbol(_sdata)));
1100
1101         debug_checkwx();
1102 }
1103
1104 int kern_addr_valid(unsigned long addr)
1105 {
1106         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1107         pgd_t *pgd;
1108         pud_t *pud;
1109         pmd_t *pmd;
1110         pte_t *pte;
1111
1112         if (above != 0 && above != -1UL)
1113                 return 0;
1114
1115         pgd = pgd_offset_k(addr);
1116         if (pgd_none(*pgd))
1117                 return 0;
1118
1119         pud = pud_offset(pgd, addr);
1120         if (pud_none(*pud))
1121                 return 0;
1122
1123         if (pud_large(*pud))
1124                 return pfn_valid(pud_pfn(*pud));
1125
1126         pmd = pmd_offset(pud, addr);
1127         if (pmd_none(*pmd))
1128                 return 0;
1129
1130         if (pmd_large(*pmd))
1131                 return pfn_valid(pmd_pfn(*pmd));
1132
1133         pte = pte_offset_kernel(pmd, addr);
1134         if (pte_none(*pte))
1135                 return 0;
1136
1137         return pfn_valid(pte_pfn(*pte));
1138 }
1139
1140 static unsigned long probe_memory_block_size(void)
1141 {
1142         unsigned long bz = MIN_MEMORY_BLOCK_SIZE;
1143
1144         /* if system is UV or has 64GB of RAM or more, use large blocks */
1145         if (is_uv_system() || ((max_pfn << PAGE_SHIFT) >= (64UL << 30)))
1146                 bz = 2UL << 30; /* 2GB */
1147
1148         pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1149
1150         return bz;
1151 }
1152
1153 static unsigned long memory_block_size_probed;
1154 unsigned long memory_block_size_bytes(void)
1155 {
1156         if (!memory_block_size_probed)
1157                 memory_block_size_probed = probe_memory_block_size();
1158
1159         return memory_block_size_probed;
1160 }
1161
1162 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1163 /*
1164  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1165  */
1166 static long __meminitdata addr_start, addr_end;
1167 static void __meminitdata *p_start, *p_end;
1168 static int __meminitdata node_start;
1169
1170 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1171                 unsigned long end, int node, struct vmem_altmap *altmap)
1172 {
1173         unsigned long addr;
1174         unsigned long next;
1175         pgd_t *pgd;
1176         pud_t *pud;
1177         pmd_t *pmd;
1178
1179         for (addr = start; addr < end; addr = next) {
1180                 next = pmd_addr_end(addr, end);
1181
1182                 pgd = vmemmap_pgd_populate(addr, node);
1183                 if (!pgd)
1184                         return -ENOMEM;
1185
1186                 pud = vmemmap_pud_populate(pgd, addr, node);
1187                 if (!pud)
1188                         return -ENOMEM;
1189
1190                 pmd = pmd_offset(pud, addr);
1191                 if (pmd_none(*pmd)) {
1192                         void *p;
1193
1194                         p = __vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
1195                         if (p) {
1196                                 pte_t entry;
1197
1198                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1199                                                 PAGE_KERNEL_LARGE);
1200                                 set_pmd(pmd, __pmd(pte_val(entry)));
1201
1202                                 /* check to see if we have contiguous blocks */
1203                                 if (p_end != p || node_start != node) {
1204                                         if (p_start)
1205                                                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1206                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1207                                         addr_start = addr;
1208                                         node_start = node;
1209                                         p_start = p;
1210                                 }
1211
1212                                 addr_end = addr + PMD_SIZE;
1213                                 p_end = p + PMD_SIZE;
1214                                 continue;
1215                         } else if (altmap)
1216                                 return -ENOMEM; /* no fallback */
1217                 } else if (pmd_large(*pmd)) {
1218                         vmemmap_verify((pte_t *)pmd, node, addr, next);
1219                         continue;
1220                 }
1221                 pr_warn_once("vmemmap: falling back to regular page backing\n");
1222                 if (vmemmap_populate_basepages(addr, next, node))
1223                         return -ENOMEM;
1224         }
1225         return 0;
1226 }
1227
1228 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
1229 {
1230         struct vmem_altmap *altmap = to_vmem_altmap(start);
1231         int err;
1232
1233         if (boot_cpu_has(X86_FEATURE_PSE))
1234                 err = vmemmap_populate_hugepages(start, end, node, altmap);
1235         else if (altmap) {
1236                 pr_err_once("%s: no cpu support for altmap allocations\n",
1237                                 __func__);
1238                 err = -ENOMEM;
1239         } else
1240                 err = vmemmap_populate_basepages(start, end, node);
1241         if (!err)
1242                 sync_global_pgds(start, end - 1, 0);
1243         return err;
1244 }
1245
1246 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1247 void register_page_bootmem_memmap(unsigned long section_nr,
1248                                   struct page *start_page, unsigned long size)
1249 {
1250         unsigned long addr = (unsigned long)start_page;
1251         unsigned long end = (unsigned long)(start_page + size);
1252         unsigned long next;
1253         pgd_t *pgd;
1254         pud_t *pud;
1255         pmd_t *pmd;
1256         unsigned int nr_pages;
1257         struct page *page;
1258
1259         for (; addr < end; addr = next) {
1260                 pte_t *pte = NULL;
1261
1262                 pgd = pgd_offset_k(addr);
1263                 if (pgd_none(*pgd)) {
1264                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1265                         continue;
1266                 }
1267                 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1268
1269                 pud = pud_offset(pgd, addr);
1270                 if (pud_none(*pud)) {
1271                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1272                         continue;
1273                 }
1274                 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1275
1276                 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1277                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1278                         pmd = pmd_offset(pud, addr);
1279                         if (pmd_none(*pmd))
1280                                 continue;
1281                         get_page_bootmem(section_nr, pmd_page(*pmd),
1282                                          MIX_SECTION_INFO);
1283
1284                         pte = pte_offset_kernel(pmd, addr);
1285                         if (pte_none(*pte))
1286                                 continue;
1287                         get_page_bootmem(section_nr, pte_page(*pte),
1288                                          SECTION_INFO);
1289                 } else {
1290                         next = pmd_addr_end(addr, end);
1291
1292                         pmd = pmd_offset(pud, addr);
1293                         if (pmd_none(*pmd))
1294                                 continue;
1295
1296                         nr_pages = 1 << (get_order(PMD_SIZE));
1297                         page = pmd_page(*pmd);
1298                         while (nr_pages--)
1299                                 get_page_bootmem(section_nr, page++,
1300                                                  SECTION_INFO);
1301                 }
1302         }
1303 }
1304 #endif
1305
1306 void __meminit vmemmap_populate_print_last(void)
1307 {
1308         if (p_start) {
1309                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1310                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1311                 p_start = NULL;
1312                 p_end = NULL;
1313                 node_start = 0;
1314         }
1315 }
1316 #endif