arch/x86/mm/init_32.c

   1 /*
   2  *
   3  *  Copyright (C) 1995  Linus Torvalds
   4  *
   5  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
   6  */
   7
   8 #include <linux/module.h>
   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/hugetlb.h>
  19 #include <linux/swap.h>
  20 #include <linux/smp.h>
  21 #include <linux/init.h>
  22 #include <linux/highmem.h>
  23 #include <linux/pagemap.h>
  24 #include <linux/pci.h>
  25 #include <linux/pfn.h>
  26 #include <linux/poison.h>
  27 #include <linux/bootmem.h>
  28 #include <linux/slab.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/memory_hotplug.h>
  31 #include <linux/initrd.h>
  32 #include <linux/cpumask.h>
  33
  34 #include <asm/asm.h>
  35 #include <asm/bios_ebda.h>
  36 #include <asm/processor.h>
  37 #include <asm/system.h>
  38 #include <asm/uaccess.h>
  39 #include <asm/pgtable.h>
  40 #include <asm/dma.h>
  41 #include <asm/fixmap.h>
  42 #include <asm/e820.h>
  43 #include <asm/apic.h>
  44 #include <asm/bugs.h>
  45 #include <asm/tlb.h>
  46 #include <asm/tlbflush.h>
  47 #include <asm/pgalloc.h>
  48 #include <asm/sections.h>
  49 #include <asm/paravirt.h>
  50 #include <asm/setup.h>
  51 #include <asm/cacheflush.h>
  52
  53 unsigned long max_low_pfn_mapped;
  54 unsigned long max_pfn_mapped;
  55
  56 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  57 unsigned long highstart_pfn, highend_pfn;
  58
  59 static noinline int do_test_wp_bit(void);
  60
  61
  62 static unsigned long __initdata table_start;
  63 static unsigned long __meminitdata table_end;
  64 static unsigned long __meminitdata table_top;
  65
  66 static int __initdata after_init_bootmem;
  67
  68 static __init void *alloc_low_page(void)
  69 {
  70         unsigned long pfn = table_end++;
  71         void *adr;
  72
  73         if (pfn >= table_top)
  74                 panic("alloc_low_page: ran out of memory");
  75
  76         adr = __va(pfn * PAGE_SIZE);
  77         memset(adr, 0, PAGE_SIZE);
  78         return adr;
  79 }
  80
  81 /*
  82  * Creates a middle page table and puts a pointer to it in the
  83  * given global directory entry. This only returns the gd entry
  84  * in non-PAE compilation mode, since the middle layer is folded.
  85  */
  86 static pmd_t * __init one_md_table_init(pgd_t *pgd)
  87 {
  88         pud_t *pud;
  89         pmd_t *pmd_table;
  90
  91 #ifdef CONFIG_X86_PAE
  92         if (!(pgd_val(*pgd) & _PAGE_PRESENT)) {
  93                 if (after_init_bootmem)
  94                         pmd_table = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
  95                 else
  96                         pmd_table = (pmd_t *)alloc_low_page();
  97                 paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT);
  98                 set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
  99                 pud = pud_offset(pgd, 0);
 100                 BUG_ON(pmd_table != pmd_offset(pud, 0));
 101
 102                 return pmd_table;
 103         }
 104 #endif
 105         pud = pud_offset(pgd, 0);
 106         pmd_table = pmd_offset(pud, 0);
 107
 108         return pmd_table;
 109 }
 110
 111 /*
 112  * Create a page table and place a pointer to it in a middle page
 113  * directory entry:
 114  */
 115 static pte_t * __init one_page_table_init(pmd_t *pmd)
 116 {
 117         if (!(pmd_val(*pmd) & _PAGE_PRESENT)) {
 118                 pte_t *page_table = NULL;
 119
 120                 if (after_init_bootmem) {
 121 #ifdef CONFIG_DEBUG_PAGEALLOC
 122                         page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
 123 #endif
 124                         if (!page_table)
 125                                 page_table =
 126                                 (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
 127                 } else
 128                         page_table = (pte_t *)alloc_low_page();
 129
 130                 paravirt_alloc_pte(&init_mm, __pa(page_table) >> PAGE_SHIFT);
 131                 set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE));
 132                 BUG_ON(page_table != pte_offset_kernel(pmd, 0));
 133         }
 134
 135         return pte_offset_kernel(pmd, 0);
 136 }
 137
 138 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
 139 {
 140         int pgd_idx = pgd_index(vaddr);
 141         int pmd_idx = pmd_index(vaddr);
 142
 143         return one_md_table_init(swapper_pg_dir + pgd_idx) + pmd_idx;
 144 }
 145
 146 pte_t * __init populate_extra_pte(unsigned long vaddr)
 147 {
 148         int pte_idx = pte_index(vaddr);
 149         pmd_t *pmd;
 150
 151         pmd = populate_extra_pmd(vaddr);
 152         return one_page_table_init(pmd) + pte_idx;
 153 }
 154
 155 static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
 156                                            unsigned long vaddr, pte_t *lastpte)
 157 {
 158 #ifdef CONFIG_HIGHMEM
 159         /*
 160          * Something (early fixmap) may already have put a pte
 161          * page here, which causes the page table allocation
 162          * to become nonlinear. Attempt to fix it, and if it
 163          * is still nonlinear then we have to bug.
 164          */
 165         int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT;
 166         int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT;
 167
 168         if (pmd_idx_kmap_begin != pmd_idx_kmap_end
 169             && (vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin
 170             && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end
 171             && ((__pa(pte) >> PAGE_SHIFT) < table_start
 172                 || (__pa(pte) >> PAGE_SHIFT) >= table_end)) {
 173                 pte_t *newpte;
 174                 int i;
 175
 176                 BUG_ON(after_init_bootmem);
 177                 newpte = alloc_low_page();
 178                 for (i = 0; i < PTRS_PER_PTE; i++)
 179                         set_pte(newpte + i, pte[i]);
 180
 181                 paravirt_alloc_pte(&init_mm, __pa(newpte) >> PAGE_SHIFT);
 182                 set_pmd(pmd, __pmd(__pa(newpte)|_PAGE_TABLE));
 183                 BUG_ON(newpte != pte_offset_kernel(pmd, 0));
 184                 __flush_tlb_all();
 185
 186                 paravirt_release_pte(__pa(pte) >> PAGE_SHIFT);
 187                 pte = newpte;
 188         }
 189         BUG_ON(vaddr < fix_to_virt(FIX_KMAP_BEGIN - 1)
 190                && vaddr > fix_to_virt(FIX_KMAP_END)
 191                && lastpte && lastpte + PTRS_PER_PTE != pte);
 192 #endif
 193         return pte;
 194 }
 195
 196 /*
 197  * This function initializes a certain range of kernel virtual memory
 198  * with new bootmem page tables, everywhere page tables are missing in
 199  * the given range.
 200  *
 201  * NOTE: The pagetables are allocated contiguous on the physical space
 202  * so we can cache the place of the first one and move around without
 203  * checking the pgd every time.
 204  */
 205 static void __init
 206 page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
 207 {
 208         int pgd_idx, pmd_idx;
 209         unsigned long vaddr;
 210         pgd_t *pgd;
 211         pmd_t *pmd;
 212         pte_t *pte = NULL;
 213
 214         vaddr = start;
 215         pgd_idx = pgd_index(vaddr);
 216         pmd_idx = pmd_index(vaddr);
 217         pgd = pgd_base + pgd_idx;
 218
 219         for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
 220                 pmd = one_md_table_init(pgd);
 221                 pmd = pmd + pmd_index(vaddr);
 222                 for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
 223                                                         pmd++, pmd_idx++) {
 224                         pte = page_table_kmap_check(one_page_table_init(pmd),
 225                                                     pmd, vaddr, pte);
 226
 227                         vaddr += PMD_SIZE;
 228                 }
 229                 pmd_idx = 0;
 230         }
 231 }
 232
 233 static inline int is_kernel_text(unsigned long addr)
 234 {
 235         if (addr >= PAGE_OFFSET && addr <= (unsigned long)__init_end)
 236                 return 1;
 237         return 0;
 238 }
 239
 240 /*
 241  * This maps the physical memory to kernel virtual address space, a total
 242  * of max_low_pfn pages, by creating page tables starting from address
 243  * PAGE_OFFSET:
 244  */
 245 static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
 246                                                 unsigned long start_pfn,
 247                                                 unsigned long end_pfn,
 248                                                 int use_pse)
 249 {
 250         int pgd_idx, pmd_idx, pte_ofs;
 251         unsigned long pfn;
 252         pgd_t *pgd;
 253         pmd_t *pmd;
 254         pte_t *pte;
 255         unsigned pages_2m, pages_4k;
 256         int mapping_iter;
 257
 258         /*
 259          * First iteration will setup identity mapping using large/small pages
 260          * based on use_pse, with other attributes same as set by
 261          * the early code in head_32.S
 262          *
 263          * Second iteration will setup the appropriate attributes (NX, GLOBAL..)
 264          * as desired for the kernel identity mapping.
 265          *
 266          * This two pass mechanism conforms to the TLB app note which says:
 267          *
 268          *     "Software should not write to a paging-structure entry in a way
 269          *      that would change, for any linear address, both the page size
 270          *      and either the page frame or attributes."
 271          */
 272         mapping_iter = 1;
 273
 274         if (!cpu_has_pse)
 275                 use_pse = 0;
 276
 277 repeat:
 278         pages_2m = pages_4k = 0;
 279         pfn = start_pfn;
 280         pgd_idx = pgd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
 281         pgd = pgd_base + pgd_idx;
 282         for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) {
 283                 pmd = one_md_table_init(pgd);
 284
 285                 if (pfn >= end_pfn)
 286                         continue;
 287 #ifdef CONFIG_X86_PAE
 288                 pmd_idx = pmd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
 289                 pmd += pmd_idx;
 290 #else
 291                 pmd_idx = 0;
 292 #endif
 293                 for (; pmd_idx < PTRS_PER_PMD && pfn < end_pfn;
 294                      pmd++, pmd_idx++) {
 295                         unsigned int addr = pfn * PAGE_SIZE + PAGE_OFFSET;
 296
 297                         /*
 298                          * Map with big pages if possible, otherwise
 299                          * create normal page tables:
 300                          */
 301                         if (use_pse) {
 302                                 unsigned int addr2;
 303                                 pgprot_t prot = PAGE_KERNEL_LARGE;
 304                                 /*
 305                                  * first pass will use the same initial
 306                                  * identity mapping attribute + _PAGE_PSE.
 307                                  */
 308                                 pgprot_t init_prot =
 309                                         __pgprot(PTE_IDENT_ATTR |
 310                                                  _PAGE_PSE);
 311
 312                                 addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
 313                                         PAGE_OFFSET + PAGE_SIZE-1;
 314
 315                                 if (is_kernel_text(addr) ||
 316                                     is_kernel_text(addr2))
 317                                         prot = PAGE_KERNEL_LARGE_EXEC;
 318
 319                                 pages_2m++;
 320                                 if (mapping_iter == 1)
 321                                         set_pmd(pmd, pfn_pmd(pfn, init_prot));
 322                                 else
 323                                         set_pmd(pmd, pfn_pmd(pfn, prot));
 324
 325                                 pfn += PTRS_PER_PTE;
 326                                 continue;
 327                         }
 328                         pte = one_page_table_init(pmd);
 329
 330                         pte_ofs = pte_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
 331                         pte += pte_ofs;
 332                         for (; pte_ofs < PTRS_PER_PTE && pfn < end_pfn;
 333                              pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
 334                                 pgprot_t prot = PAGE_KERNEL;
 335                                 /*
 336                                  * first pass will use the same initial
 337                                  * identity mapping attribute.
 338                                  */
 339                                 pgprot_t init_prot = __pgprot(PTE_IDENT_ATTR);
 340
 341                                 if (is_kernel_text(addr))
 342                                         prot = PAGE_KERNEL_EXEC;
 343
 344                                 pages_4k++;
 345                                 if (mapping_iter == 1)
 346                                         set_pte(pte, pfn_pte(pfn, init_prot));
 347                                 else
 348                                         set_pte(pte, pfn_pte(pfn, prot));
 349                         }
 350                 }
 351         }
 352         if (mapping_iter == 1) {
 353                 /*
 354                  * update direct mapping page count only in the first
 355                  * iteration.
 356                  */
 357                 update_page_count(PG_LEVEL_2M, pages_2m);
 358                 update_page_count(PG_LEVEL_4K, pages_4k);
 359
 360                 /*
 361                  * local global flush tlb, which will flush the previous
 362                  * mappings present in both small and large page TLB's.
 363                  */
 364                 __flush_tlb_all();
 365
 366                 /*
 367                  * Second iteration will set the actual desired PTE attributes.
 368                  */
 369                 mapping_iter = 2;
 370                 goto repeat;
 371         }
 372 }
 373
 374 /*
 375  * devmem_is_allowed() checks to see if /dev/mem access to a certain address
 376  * is valid. The argument is a physical page number.
 377  *
 378  *
 379  * On x86, access has to be given to the first megabyte of ram because that area
 380  * contains bios code and data regions used by X and dosemu and similar apps.
 381  * Access has to be given to non-kernel-ram areas as well, these contain the PCI
 382  * mmio resources as well as potential bios/acpi data regions.
 383  */
 384 int devmem_is_allowed(unsigned long pagenr)
 385 {
 386         if (pagenr <= 256)
 387                 return 1;
 388         if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
 389                 return 0;
 390         if (!page_is_ram(pagenr))
 391                 return 1;
 392         return 0;
 393 }
 394
 395 pte_t *kmap_pte;
 396 pgprot_t kmap_prot;
 397
 398 static inline pte_t *kmap_get_fixmap_pte(unsigned long vaddr)
 399 {
 400         return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
 401                         vaddr), vaddr), vaddr);
 402 }
 403
 404 static void __init kmap_init(void)
 405 {
 406         unsigned long kmap_vstart;
 407
 408         /*
 409          * Cache the first kmap pte:
 410          */
 411         kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 412         kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
 413
 414         kmap_prot = PAGE_KERNEL;
 415 }
 416
 417 #ifdef CONFIG_HIGHMEM
 418 static void __init permanent_kmaps_init(pgd_t *pgd_base)
 419 {
 420         unsigned long vaddr;
 421         pgd_t *pgd;
 422         pud_t *pud;
 423         pmd_t *pmd;
 424         pte_t *pte;
 425
 426         vaddr = PKMAP_BASE;
 427         page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
 428
 429         pgd = swapper_pg_dir + pgd_index(vaddr);
 430         pud = pud_offset(pgd, vaddr);
 431         pmd = pmd_offset(pud, vaddr);
 432         pte = pte_offset_kernel(pmd, vaddr);
 433         pkmap_page_table = pte;
 434 }
 435
 436 static void __init add_one_highpage_init(struct page *page, int pfn)
 437 {
 438         ClearPageReserved(page);
 439         init_page_count(page);
 440         __free_page(page);
 441         totalhigh_pages++;
 442 }
 443
 444 struct add_highpages_data {
 445         unsigned long start_pfn;
 446         unsigned long end_pfn;
 447 };
 448
 449 static int __init add_highpages_work_fn(unsigned long start_pfn,
 450                                          unsigned long end_pfn, void *datax)
 451 {
 452         int node_pfn;
 453         struct page *page;
 454         unsigned long final_start_pfn, final_end_pfn;
 455         struct add_highpages_data *data;
 456
 457         data = (struct add_highpages_data *)datax;
 458
 459         final_start_pfn = max(start_pfn, data->start_pfn);
 460         final_end_pfn = min(end_pfn, data->end_pfn);
 461         if (final_start_pfn >= final_end_pfn)
 462                 return 0;
 463
 464         for (node_pfn = final_start_pfn; node_pfn < final_end_pfn;
 465              node_pfn++) {
 466                 if (!pfn_valid(node_pfn))
 467                         continue;
 468                 page = pfn_to_page(node_pfn);
 469                 add_one_highpage_init(page, node_pfn);
 470         }
 471
 472         return 0;
 473
 474 }
 475
 476 void __init add_highpages_with_active_regions(int nid, unsigned long start_pfn,
 477                                               unsigned long end_pfn)
 478 {
 479         struct add_highpages_data data;
 480
 481         data.start_pfn = start_pfn;
 482         data.end_pfn = end_pfn;
 483
 484         work_with_active_regions(nid, add_highpages_work_fn, &data);
 485 }
 486
 487 #else
 488 static inline void permanent_kmaps_init(pgd_t *pgd_base)
 489 {
 490 }
 491 #endif /* CONFIG_HIGHMEM */
 492
 493 void __init native_pagetable_setup_start(pgd_t *base)
 494 {
 495         unsigned long pfn, va;
 496         pgd_t *pgd;
 497         pud_t *pud;
 498         pmd_t *pmd;
 499         pte_t *pte;
 500
 501         /*
 502          * Remove any mappings which extend past the end of physical
 503          * memory from the boot time page table:
 504          */
 505         for (pfn = max_low_pfn + 1; pfn < 1<<(32-PAGE_SHIFT); pfn++) {
 506                 va = PAGE_OFFSET + (pfn<<PAGE_SHIFT);
 507                 pgd = base + pgd_index(va);
 508                 if (!pgd_present(*pgd))
 509                         break;
 510
 511                 pud = pud_offset(pgd, va);
 512                 pmd = pmd_offset(pud, va);
 513                 if (!pmd_present(*pmd))
 514                         break;
 515
 516                 pte = pte_offset_kernel(pmd, va);
 517                 if (!pte_present(*pte))
 518                         break;
 519
 520                 pte_clear(NULL, va, pte);
 521         }
 522         paravirt_alloc_pmd(&init_mm, __pa(base) >> PAGE_SHIFT);
 523 }
 524
 525 void __init native_pagetable_setup_done(pgd_t *base)
 526 {
 527 }
 528
 529 /*
 530  * Build a proper pagetable for the kernel mappings.  Up until this
 531  * point, we've been running on some set of pagetables constructed by
 532  * the boot process.
 533  *
 534  * If we're booting on native hardware, this will be a pagetable
 535  * constructed in arch/x86/kernel/head_32.S.  The root of the
 536  * pagetable will be swapper_pg_dir.
 537  *
 538  * If we're booting paravirtualized under a hypervisor, then there are
 539  * more options: we may already be running PAE, and the pagetable may
 540  * or may not be based in swapper_pg_dir.  In any case,
 541  * paravirt_pagetable_setup_start() will set up swapper_pg_dir
 542  * appropriately for the rest of the initialization to work.
 543  *
 544  * In general, pagetable_init() assumes that the pagetable may already
 545  * be partially populated, and so it avoids stomping on any existing
 546  * mappings.
 547  */
 548 static void __init early_ioremap_page_table_range_init(pgd_t *pgd_base)
 549 {
 550         unsigned long vaddr, end;
 551
 552         /*
 553          * Fixed mappings, only the page table structure has to be
 554          * created - mappings will be set by set_fixmap():
 555          */
 556         vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
 557         end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
 558         page_table_range_init(vaddr, end, pgd_base);
 559         early_ioremap_reset();
 560 }
 561
 562 static void __init pagetable_init(void)
 563 {
 564         pgd_t *pgd_base = swapper_pg_dir;
 565
 566         permanent_kmaps_init(pgd_base);
 567 }
 568
 569 #ifdef CONFIG_ACPI_SLEEP
 570 /*
 571  * ACPI suspend needs this for resume, because things like the intel-agp
 572  * driver might have split up a kernel 4MB mapping.
 573  */
 574 char swsusp_pg_dir[PAGE_SIZE]
 575         __attribute__ ((aligned(PAGE_SIZE)));
 576
 577 static inline void save_pg_dir(void)
 578 {
 579         memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE);
 580 }
 581 #else /* !CONFIG_ACPI_SLEEP */
 582 static inline void save_pg_dir(void)
 583 {
 584 }
 585 #endif /* !CONFIG_ACPI_SLEEP */
 586
 587 void zap_low_mappings(void)
 588 {
 589         int i;
 590
 591         /*
 592          * Zap initial low-memory mappings.
 593          *
 594          * Note that "pgd_clear()" doesn't do it for
 595          * us, because pgd_clear() is a no-op on i386.
 596          */
 597         for (i = 0; i < KERNEL_PGD_BOUNDARY; i++) {
 598 #ifdef CONFIG_X86_PAE
 599                 set_pgd(swapper_pg_dir+i, __pgd(1 + __pa(empty_zero_page)));
 600 #else
 601                 set_pgd(swapper_pg_dir+i, __pgd(0));
 602 #endif
 603         }
 604         flush_tlb_all();
 605 }
 606
 607 int nx_enabled;
 608
 609 pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
 610 EXPORT_SYMBOL_GPL(__supported_pte_mask);
 611
 612 #ifdef CONFIG_X86_PAE
 613
 614 static int disable_nx __initdata;
 615
 616 /*
 617  * noexec = on|off
 618  *
 619  * Control non executable mappings.
 620  *
 621  * on      Enable
 622  * off     Disable
 623  */
 624 static int __init noexec_setup(char *str)
 625 {
 626         if (!str || !strcmp(str, "on")) {
 627                 if (cpu_has_nx) {
 628                         __supported_pte_mask |= _PAGE_NX;
 629                         disable_nx = 0;
 630                 }
 631         } else {
 632                 if (!strcmp(str, "off")) {
 633                         disable_nx = 1;
 634                         __supported_pte_mask &= ~_PAGE_NX;
 635                 } else {
 636                         return -EINVAL;
 637                 }
 638         }
 639
 640         return 0;
 641 }
 642 early_param("noexec", noexec_setup);
 643
 644 static void __init set_nx(void)
 645 {
 646         unsigned int v[4], l, h;
 647
 648         if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
 649                 cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
 650
 651                 if ((v[3] & (1 << 20)) && !disable_nx) {
 652                         rdmsr(MSR_EFER, l, h);
 653                         l |= EFER_NX;
 654                         wrmsr(MSR_EFER, l, h);
 655                         nx_enabled = 1;
 656                         __supported_pte_mask |= _PAGE_NX;
 657                 }
 658         }
 659 }
 660 #endif
 661
 662 /* user-defined highmem size */
 663 static unsigned int highmem_pages = -1;
 664
 665 /*
 666  * highmem=size forces highmem to be exactly 'size' bytes.
 667  * This works even on boxes that have no highmem otherwise.
 668  * This also works to reduce highmem size on bigger boxes.
 669  */
 670 static int __init parse_highmem(char *arg)
 671 {
 672         if (!arg)
 673                 return -EINVAL;
 674
 675         highmem_pages = memparse(arg, &arg) >> PAGE_SHIFT;
 676         return 0;
 677 }
 678 early_param("highmem", parse_highmem);
 679
 680 #define MSG_HIGHMEM_TOO_BIG \
 681         "highmem size (%luMB) is bigger than pages available (%luMB)!\n"
 682
 683 #define MSG_LOWMEM_TOO_SMALL \
 684         "highmem size (%luMB) results in <64MB lowmem, ignoring it!\n"
 685 /*
 686  * All of RAM fits into lowmem - but if user wants highmem
 687  * artificially via the highmem=x boot parameter then create
 688  * it:
 689  */
 690 void __init lowmem_pfn_init(void)
 691 {
 692         /* max_low_pfn is 0, we already have early_res support */
 693         max_low_pfn = max_pfn;
 694
 695         if (highmem_pages == -1)
 696                 highmem_pages = 0;
 697 #ifdef CONFIG_HIGHMEM
 698         if (highmem_pages >= max_pfn) {
 699                 printk(KERN_ERR MSG_HIGHMEM_TOO_BIG,
 700                         pages_to_mb(highmem_pages), pages_to_mb(max_pfn));
 701                 highmem_pages = 0;
 702         }
 703         if (highmem_pages) {
 704                 if (max_low_pfn - highmem_pages < 64*1024*1024/PAGE_SIZE) {
 705                         printk(KERN_ERR MSG_LOWMEM_TOO_SMALL,
 706                                 pages_to_mb(highmem_pages));
 707                         highmem_pages = 0;
 708                 }
 709                 max_low_pfn -= highmem_pages;
 710         }
 711 #else
 712         if (highmem_pages)
 713                 printk(KERN_ERR "ignoring highmem size on non-highmem kernel!\n");
 714 #endif
 715 }
 716
 717 #define MSG_HIGHMEM_TOO_SMALL \
 718         "only %luMB highmem pages available, ignoring highmem size of %luMB!\n"
 719
 720 #define MSG_HIGHMEM_TRIMMED \
 721         "Warning: only 4GB will be used. Use a HIGHMEM64G enabled kernel!\n"
 722 /*
 723  * We have more RAM than fits into lowmem - we try to put it into
 724  * highmem, also taking the highmem=x boot parameter into account:
 725  */
 726 void __init highmem_pfn_init(void)
 727 {
 728         max_low_pfn = MAXMEM_PFN;
 729
 730         if (highmem_pages == -1)
 731                 highmem_pages = max_pfn - MAXMEM_PFN;
 732
 733         if (highmem_pages + MAXMEM_PFN < max_pfn)
 734                 max_pfn = MAXMEM_PFN + highmem_pages;
 735
 736         if (highmem_pages + MAXMEM_PFN > max_pfn) {
 737                 printk(KERN_WARNING MSG_HIGHMEM_TOO_SMALL,
 738                         pages_to_mb(max_pfn - MAXMEM_PFN),
 739                         pages_to_mb(highmem_pages));
 740                 highmem_pages = 0;
 741         }
 742 #ifndef CONFIG_HIGHMEM
 743         /* Maximum memory usable is what is directly addressable */
 744         printk(KERN_WARNING "Warning only %ldMB will be used.\n", MAXMEM>>20);
 745         if (max_pfn > MAX_NONPAE_PFN)
 746                 printk(KERN_WARNING "Use a HIGHMEM64G enabled kernel.\n");
 747         else
 748                 printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
 749         max_pfn = MAXMEM_PFN;
 750 #else /* !CONFIG_HIGHMEM */
 751 #ifndef CONFIG_HIGHMEM64G
 752         if (max_pfn > MAX_NONPAE_PFN) {
 753                 max_pfn = MAX_NONPAE_PFN;
 754                 printk(KERN_WARNING MSG_HIGHMEM_TRIMMED);
 755         }
 756 #endif /* !CONFIG_HIGHMEM64G */
 757 #endif /* !CONFIG_HIGHMEM */
 758 }
 759
 760 /*
 761  * Determine low and high memory ranges:
 762  */
 763 void __init find_low_pfn_range(void)
 764 {
 765         /* it could update max_pfn */
 766
 767         if (max_pfn <= MAXMEM_PFN)
 768                 lowmem_pfn_init();
 769         else
 770                 highmem_pfn_init();
 771 }
 772
 773 #ifndef CONFIG_NEED_MULTIPLE_NODES
 774 void __init initmem_init(unsigned long start_pfn,
 775                                   unsigned long end_pfn)
 776 {
 777 #ifdef CONFIG_HIGHMEM
 778         highstart_pfn = highend_pfn = max_pfn;
 779         if (max_pfn > max_low_pfn)
 780                 highstart_pfn = max_low_pfn;
 781         memory_present(0, 0, highend_pfn);
 782         e820_register_active_regions(0, 0, highend_pfn);
 783         printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 784                 pages_to_mb(highend_pfn - highstart_pfn));
 785         num_physpages = highend_pfn;
 786         high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
 787 #else
 788         memory_present(0, 0, max_low_pfn);
 789         e820_register_active_regions(0, 0, max_low_pfn);
 790         num_physpages = max_low_pfn;
 791         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
 792 #endif
 793 #ifdef CONFIG_FLATMEM
 794         max_mapnr = num_physpages;
 795 #endif
 796         printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
 797                         pages_to_mb(max_low_pfn));
 798
 799         setup_bootmem_allocator();
 800 }
 801 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 802
 803 static void __init zone_sizes_init(void)
 804 {
 805         unsigned long max_zone_pfns[MAX_NR_ZONES];
 806         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 807         max_zone_pfns[ZONE_DMA] =
 808                 virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 809         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 810 #ifdef CONFIG_HIGHMEM
 811         max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
 812 #endif
 813
 814         free_area_init_nodes(max_zone_pfns);
 815 }
 816
 817 void __init setup_bootmem_allocator(void)
 818 {
 819         int i;
 820         unsigned long bootmap_size, bootmap;
 821         /*
 822          * Initialize the boot-time allocator (with low memory only):
 823          */
 824         bootmap_size = bootmem_bootmap_pages(max_low_pfn)<<PAGE_SHIFT;
 825         bootmap = find_e820_area(min_low_pfn<<PAGE_SHIFT,
 826                                  max_pfn_mapped<<PAGE_SHIFT, bootmap_size,
 827                                  PAGE_SIZE);
 828         if (bootmap == -1L)
 829                 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
 830         reserve_early(bootmap, bootmap + bootmap_size, "BOOTMAP");
 831
 832         /* don't touch min_low_pfn */
 833         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
 834                                          min_low_pfn, max_low_pfn);
 835         printk(KERN_INFO "  mapped low ram: 0 - %08lx\n",
 836                  max_pfn_mapped<<PAGE_SHIFT);
 837         printk(KERN_INFO "  low ram: %08lx - %08lx\n",
 838                  min_low_pfn<<PAGE_SHIFT, max_low_pfn<<PAGE_SHIFT);
 839         printk(KERN_INFO "  bootmap %08lx - %08lx\n",
 840                  bootmap, bootmap + bootmap_size);
 841         for_each_online_node(i)
 842                 free_bootmem_with_active_regions(i, max_low_pfn);
 843         early_res_to_bootmem(0, max_low_pfn<<PAGE_SHIFT);
 844
 845         after_init_bootmem = 1;
 846 }
 847
 848 static void __init find_early_table_space(unsigned long end, int use_pse)
 849 {
 850         unsigned long puds, pmds, ptes, tables, start;
 851
 852         puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
 853         tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
 854
 855         pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
 856         tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
 857
 858         if (use_pse) {
 859                 unsigned long extra;
 860
 861                 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
 862                 extra += PMD_SIZE;
 863                 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
 864         } else
 865                 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
 866
 867         tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
 868
 869         /* for fixmap */
 870         tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
 871
 872         /*
 873          * RED-PEN putting page tables only on node 0 could
 874          * cause a hotspot and fill up ZONE_DMA. The page tables
 875          * need roughly 0.5KB per GB.
 876          */
 877         start = 0x7000;
 878         table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
 879                                         tables, PAGE_SIZE);
 880         if (table_start == -1UL)
 881                 panic("Cannot find space for the kernel page tables");
 882
 883         table_start >>= PAGE_SHIFT;
 884         table_end = table_start;
 885         table_top = table_start + (tables>>PAGE_SHIFT);
 886
 887         printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
 888                 end, table_start << PAGE_SHIFT,
 889                 (table_start << PAGE_SHIFT) + tables);
 890 }
 891
 892 unsigned long __init_refok init_memory_mapping(unsigned long start,
 893                                                 unsigned long end)
 894 {
 895         pgd_t *pgd_base = swapper_pg_dir;
 896         unsigned long start_pfn, end_pfn;
 897         unsigned long big_page_start;
 898 #ifdef CONFIG_DEBUG_PAGEALLOC
 899         /*
 900          * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
 901          * This will simplify cpa(), which otherwise needs to support splitting
 902          * large pages into small in interrupt context, etc.
 903          */
 904         int use_pse = 0;
 905 #else
 906         int use_pse = cpu_has_pse;
 907 #endif
 908
 909         /*
 910          * Find space for the kernel direct mapping tables.
 911          */
 912         if (!after_init_bootmem)
 913                 find_early_table_space(end, use_pse);
 914
 915 #ifdef CONFIG_X86_PAE
 916         set_nx();
 917         if (nx_enabled)
 918                 printk(KERN_INFO "NX (Execute Disable) protection: active\n");
 919 #endif
 920
 921         /* Enable PSE if available */
 922         if (cpu_has_pse)
 923                 set_in_cr4(X86_CR4_PSE);
 924
 925         /* Enable PGE if available */
 926         if (cpu_has_pge) {
 927                 set_in_cr4(X86_CR4_PGE);
 928                 __supported_pte_mask |= _PAGE_GLOBAL;
 929         }
 930
 931         /*
 932          * Don't use a large page for the first 2/4MB of memory
 933          * because there are often fixed size MTRRs in there
 934          * and overlapping MTRRs into large pages can cause
 935          * slowdowns.
 936          */
 937         big_page_start = PMD_SIZE;
 938
 939         if (start < big_page_start) {
 940                 start_pfn = start >> PAGE_SHIFT;
 941                 end_pfn = min(big_page_start>>PAGE_SHIFT, end>>PAGE_SHIFT);
 942         } else {
 943                 /* head is not big page alignment ? */
 944                 start_pfn = start >> PAGE_SHIFT;
 945                 end_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
 946                                  << (PMD_SHIFT - PAGE_SHIFT);
 947         }
 948         if (start_pfn < end_pfn)
 949                 kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn, 0);
 950
 951         /* big page range */
 952         start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
 953                          << (PMD_SHIFT - PAGE_SHIFT);
 954         if (start_pfn < (big_page_start >> PAGE_SHIFT))
 955                 start_pfn =  big_page_start >> PAGE_SHIFT;
 956         end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
 957         if (start_pfn < end_pfn)
 958                 kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn,
 959                                              use_pse);
 960
 961         /* tail is not big page alignment ? */
 962         start_pfn = end_pfn;
 963         if (start_pfn > (big_page_start>>PAGE_SHIFT)) {
 964                 end_pfn = end >> PAGE_SHIFT;
 965                 if (start_pfn < end_pfn)
 966                         kernel_physical_mapping_init(pgd_base, start_pfn,
 967                                                          end_pfn, 0);
 968         }
 969
 970         early_ioremap_page_table_range_init(pgd_base);
 971
 972         load_cr3(swapper_pg_dir);
 973
 974         __flush_tlb_all();
 975
 976         if (!after_init_bootmem)
 977                 reserve_early(table_start << PAGE_SHIFT,
 978                                  table_end << PAGE_SHIFT, "PGTABLE");
 979
 980         if (!after_init_bootmem)
 981                 early_memtest(start, end);
 982
 983         return end >> PAGE_SHIFT;
 984 }
 985
 986
 987 /*
 988  * paging_init() sets up the page tables - note that the first 8MB are
 989  * already mapped by head.S.
 990  *
 991  * This routines also unmaps the page at virtual kernel address 0, so
 992  * that we can trap those pesky NULL-reference errors in the kernel.
 993  */
 994 void __init paging_init(void)
 995 {
 996         pagetable_init();
 997
 998         __flush_tlb_all();
 999
1000         kmap_init();
1001
1002         /*
1003          * NOTE: at this point the bootmem allocator is fully available.
1004          */
1005         sparse_init();
1006         zone_sizes_init();
1007 }
1008
1009 /*
1010  * Test if the WP bit works in supervisor mode. It isn't supported on 386's
1011  * and also on some strange 486's. All 586+'s are OK. This used to involve
1012  * black magic jumps to work around some nasty CPU bugs, but fortunately the
1013  * switch to using exceptions got rid of all that.
1014  */
1015 static void __init test_wp_bit(void)
1016 {
1017         printk(KERN_INFO
1018   "Checking if this processor honours the WP bit even in supervisor mode...");
1019
1020         /* Any page-aligned address will do, the test is non-destructive */
1021         __set_fixmap(FIX_WP_TEST, __pa(&swapper_pg_dir), PAGE_READONLY);
1022         boot_cpu_data.wp_works_ok = do_test_wp_bit();
1023         clear_fixmap(FIX_WP_TEST);
1024
1025         if (!boot_cpu_data.wp_works_ok) {
1026                 printk(KERN_CONT "No.\n");
1027 #ifdef CONFIG_X86_WP_WORKS_OK
1028                 panic(
1029   "This kernel doesn't support CPU's with broken WP. Recompile it for a 386!");
1030 #endif
1031         } else {
1032                 printk(KERN_CONT "Ok.\n");
1033         }
1034 }
1035
1036 static struct kcore_list kcore_mem, kcore_vmalloc;
1037
1038 void __init mem_init(void)
1039 {
1040         int codesize, reservedpages, datasize, initsize;
1041         int tmp;
1042
1043         pci_iommu_alloc();
1044
1045 #ifdef CONFIG_FLATMEM
1046         BUG_ON(!mem_map);
1047 #endif
1048         /* this will put all low memory onto the freelists */
1049         totalram_pages += free_all_bootmem();
1050
1051         reservedpages = 0;
1052         for (tmp = 0; tmp < max_low_pfn; tmp++)
1053                 /*
1054                  * Only count reserved RAM pages:
1055                  */
1056                 if (page_is_ram(tmp) && PageReserved(pfn_to_page(tmp)))
1057                         reservedpages++;
1058
1059         set_highmem_pages_init();
1060
1061         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
1062         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
1063         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
1064
1065         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
1066         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
1067                    VMALLOC_END-VMALLOC_START);
1068
1069         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
1070                         "%dk reserved, %dk data, %dk init, %ldk highmem)\n",
1071                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
1072                 num_physpages << (PAGE_SHIFT-10),
1073                 codesize >> 10,
1074                 reservedpages << (PAGE_SHIFT-10),
1075                 datasize >> 10,
1076                 initsize >> 10,
1077                 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))
1078                );
1079
1080         printk(KERN_INFO "virtual kernel memory layout:\n"
1081                 "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
1082 #ifdef CONFIG_HIGHMEM
1083                 "    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
1084 #endif
1085                 "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
1086                 "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
1087                 "      .init : 0x%08lx - 0x%08lx   (%4ld kB)\n"
1088                 "      .data : 0x%08lx - 0x%08lx   (%4ld kB)\n"
1089                 "      .text : 0x%08lx - 0x%08lx   (%4ld kB)\n",
1090                 FIXADDR_START, FIXADDR_TOP,
1091                 (FIXADDR_TOP - FIXADDR_START) >> 10,
1092
1093 #ifdef CONFIG_HIGHMEM
1094                 PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
1095                 (LAST_PKMAP*PAGE_SIZE) >> 10,
1096 #endif
1097
1098                 VMALLOC_START, VMALLOC_END,
1099                 (VMALLOC_END - VMALLOC_START) >> 20,
1100
1101                 (unsigned long)__va(0), (unsigned long)high_memory,
1102                 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
1103
1104                 (unsigned long)&__init_begin, (unsigned long)&__init_end,
1105                 ((unsigned long)&__init_end -
1106                  (unsigned long)&__init_begin) >> 10,
1107
1108                 (unsigned long)&_etext, (unsigned long)&_edata,
1109                 ((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
1110
1111                 (unsigned long)&_text, (unsigned long)&_etext,
1112                 ((unsigned long)&_etext - (unsigned long)&_text) >> 10);
1113
1114         /*
1115          * Check boundaries twice: Some fundamental inconsistencies can
1116          * be detected at build time already.
1117          */
1118 #define __FIXADDR_TOP (-PAGE_SIZE)
1119 #ifdef CONFIG_HIGHMEM
1120         BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE  > FIXADDR_START);
1121         BUILD_BUG_ON(VMALLOC_END                        > PKMAP_BASE);
1122 #endif
1123 #define high_memory (-128UL << 20)
1124         BUILD_BUG_ON(VMALLOC_START                      >= VMALLOC_END);
1125 #undef high_memory
1126 #undef __FIXADDR_TOP
1127
1128 #ifdef CONFIG_HIGHMEM
1129         BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE        > FIXADDR_START);
1130         BUG_ON(VMALLOC_END                              > PKMAP_BASE);
1131 #endif
1132         BUG_ON(VMALLOC_START                            >= VMALLOC_END);
1133         BUG_ON((unsigned long)high_memory               > VMALLOC_START);
1134
1135         if (boot_cpu_data.wp_works_ok < 0)
1136                 test_wp_bit();
1137
1138         save_pg_dir();
1139         zap_low_mappings();
1140 }
1141
1142 #ifdef CONFIG_MEMORY_HOTPLUG
1143 int arch_add_memory(int nid, u64 start, u64 size)
1144 {
1145         struct pglist_data *pgdata = NODE_DATA(nid);
1146         struct zone *zone = pgdata->node_zones + ZONE_HIGHMEM;
1147         unsigned long start_pfn = start >> PAGE_SHIFT;
1148         unsigned long nr_pages = size >> PAGE_SHIFT;
1149
1150         return __add_pages(nid, zone, start_pfn, nr_pages);
1151 }
1152 #endif
1153
1154 /*
1155  * This function cannot be __init, since exceptions don't work in that
1156  * section.  Put this after the callers, so that it cannot be inlined.
1157  */
1158 static noinline int do_test_wp_bit(void)
1159 {
1160         char tmp_reg;
1161         int flag;
1162
1163         __asm__ __volatile__(
1164                 "       movb %0, %1     \n"
1165                 "1:     movb %1, %0     \n"
1166                 "       xorl %2, %2     \n"
1167                 "2:                     \n"
1168                 _ASM_EXTABLE(1b,2b)
1169                 :"=m" (*(char *)fix_to_virt(FIX_WP_TEST)),
1170                  "=q" (tmp_reg),
1171                  "=r" (flag)
1172                 :"2" (1)
1173                 :"memory");
1174
1175         return flag;
1176 }
1177
1178 #ifdef CONFIG_DEBUG_RODATA
1179 const int rodata_test_data = 0xC3;
1180 EXPORT_SYMBOL_GPL(rodata_test_data);
1181
1182 void mark_rodata_ro(void)
1183 {
1184         unsigned long start = PFN_ALIGN(_text);
1185         unsigned long size = PFN_ALIGN(_etext) - start;
1186
1187 #ifndef CONFIG_DYNAMIC_FTRACE
1188         /* Dynamic tracing modifies the kernel text section */
1189         set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
1190         printk(KERN_INFO "Write protecting the kernel text: %luk\n",
1191                 size >> 10);
1192
1193 #ifdef CONFIG_CPA_DEBUG
1194         printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n",
1195                 start, start+size);
1196         set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT);
1197
1198         printk(KERN_INFO "Testing CPA: write protecting again\n");
1199         set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT);
1200 #endif
1201 #endif /* CONFIG_DYNAMIC_FTRACE */
1202
1203         start += size;
1204         size = (unsigned long)__end_rodata - start;
1205         set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
1206         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1207                 size >> 10);
1208         rodata_test();
1209
1210 #ifdef CONFIG_CPA_DEBUG
1211         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, start + size);
1212         set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
1213
1214         printk(KERN_INFO "Testing CPA: write protecting again\n");
1215         set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
1216 #endif
1217 }
1218 #endif
1219
1220 #ifdef CONFIG_BLK_DEV_INITRD
1221 void free_initrd_mem(unsigned long start, unsigned long end)
1222 {
1223         free_init_pages("initrd memory", start, end);
1224 }
1225 #endif
1226
1227 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
1228                                    int flags)
1229 {
1230         return reserve_bootmem(phys, len, flags);
1231 }