git.oblomov.eu Git - linux-2.6/blob - 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@suse.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/proc_fs.h>
  25 #include <linux/pci.h>
  26 #include <linux/pfn.h>
  27 #include <linux/poison.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/module.h>
  30 #include <linux/memory_hotplug.h>
  31 #include <linux/nmi.h>
  32
  33 #include <asm/processor.h>
  34 #include <asm/bios_ebda.h>
  35 #include <asm/system.h>
  36 #include <asm/uaccess.h>
  37 #include <asm/pgtable.h>
  38 #include <asm/pgalloc.h>
  39 #include <asm/dma.h>
  40 #include <asm/fixmap.h>
  41 #include <asm/e820.h>
  42 #include <asm/apic.h>
  43 #include <asm/tlb.h>
  44 #include <asm/mmu_context.h>
  45 #include <asm/proto.h>
  46 #include <asm/smp.h>
  47 #include <asm/sections.h>
  48 #include <asm/kdebug.h>
  49 #include <asm/numa.h>
  50 #include <asm/cacheflush.h>
  51 #include <asm/init.h>
  52
  53 /*
  54  * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
  55  * The direct mapping extends to max_pfn_mapped, so that we can directly access
  56  * apertures, ACPI and other tables without having to play with fixmaps.
  57  */
  58 unsigned long max_low_pfn_mapped;
  59 unsigned long max_pfn_mapped;
  60
  61 static unsigned long dma_reserve __initdata;
  62
  63 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  64
  65 static int __init parse_direct_gbpages_off(char *arg)
  66 {
  67         direct_gbpages = 0;
  68         return 0;
  69 }
  70 early_param("nogbpages", parse_direct_gbpages_off);
  71
  72 static int __init parse_direct_gbpages_on(char *arg)
  73 {
  74         direct_gbpages = 1;
  75         return 0;
  76 }
  77 early_param("gbpages", parse_direct_gbpages_on);
  78
  79 /*
  80  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
  81  * physical space so we can cache the place of the first one and move
  82  * around without checking the pgd every time.
  83  */
  84
  85 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
  86 EXPORT_SYMBOL_GPL(__supported_pte_mask);
  87
  88 static int disable_nx __cpuinitdata;
  89
  90 /*
  91  * noexec=on|off
  92  * Control non-executable mappings for 64-bit processes.
  93  *
  94  * on   Enable (default)
  95  * off  Disable
  96  */
  97 static int __init nonx_setup(char *str)
  98 {
  99         if (!str)
 100                 return -EINVAL;
 101         if (!strncmp(str, "on", 2)) {
 102                 __supported_pte_mask |= _PAGE_NX;
 103                 disable_nx = 0;
 104         } else if (!strncmp(str, "off", 3)) {
 105                 disable_nx = 1;
 106                 __supported_pte_mask &= ~_PAGE_NX;
 107         }
 108         return 0;
 109 }
 110 early_param("noexec", nonx_setup);
 111
 112 void __cpuinit check_efer(void)
 113 {
 114         unsigned long efer;
 115
 116         rdmsrl(MSR_EFER, efer);
 117         if (!(efer & EFER_NX) || disable_nx)
 118                 __supported_pte_mask &= ~_PAGE_NX;
 119 }
 120
 121 int force_personality32;
 122
 123 /*
 124  * noexec32=on|off
 125  * Control non executable heap for 32bit processes.
 126  * To control the stack too use noexec=off
 127  *
 128  * on   PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
 129  * off  PROT_READ implies PROT_EXEC
 130  */
 131 static int __init nonx32_setup(char *str)
 132 {
 133         if (!strcmp(str, "on"))
 134                 force_personality32 &= ~READ_IMPLIES_EXEC;
 135         else if (!strcmp(str, "off"))
 136                 force_personality32 |= READ_IMPLIES_EXEC;
 137         return 1;
 138 }
 139 __setup("noexec32=", nonx32_setup);
 140
 141 /*
 142  * NOTE: This function is marked __ref because it calls __init function
 143  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
 144  */
 145 static __ref void *spp_getpage(void)
 146 {
 147         void *ptr;
 148
 149         if (after_bootmem)
 150                 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
 151         else
 152                 ptr = alloc_bootmem_pages(PAGE_SIZE);
 153
 154         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
 155                 panic("set_pte_phys: cannot allocate page data %s\n",
 156                         after_bootmem ? "after bootmem" : "");
 157         }
 158
 159         pr_debug("spp_getpage %p\n", ptr);
 160
 161         return ptr;
 162 }
 163
 164 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
 165 {
 166         if (pgd_none(*pgd)) {
 167                 pud_t *pud = (pud_t *)spp_getpage();
 168                 pgd_populate(&init_mm, pgd, pud);
 169                 if (pud != pud_offset(pgd, 0))
 170                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
 171                                pud, pud_offset(pgd, 0));
 172         }
 173         return pud_offset(pgd, vaddr);
 174 }
 175
 176 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
 177 {
 178         if (pud_none(*pud)) {
 179                 pmd_t *pmd = (pmd_t *) spp_getpage();
 180                 pud_populate(&init_mm, pud, pmd);
 181                 if (pmd != pmd_offset(pud, 0))
 182                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
 183                                pmd, pmd_offset(pud, 0));
 184         }
 185         return pmd_offset(pud, vaddr);
 186 }
 187
 188 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
 189 {
 190         if (pmd_none(*pmd)) {
 191                 pte_t *pte = (pte_t *) spp_getpage();
 192                 pmd_populate_kernel(&init_mm, pmd, pte);
 193                 if (pte != pte_offset_kernel(pmd, 0))
 194                         printk(KERN_ERR "PAGETABLE BUG #02!\n");
 195         }
 196         return pte_offset_kernel(pmd, vaddr);
 197 }
 198
 199 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
 200 {
 201         pud_t *pud;
 202         pmd_t *pmd;
 203         pte_t *pte;
 204
 205         pud = pud_page + pud_index(vaddr);
 206         pmd = fill_pmd(pud, vaddr);
 207         pte = fill_pte(pmd, vaddr);
 208
 209         set_pte(pte, new_pte);
 210
 211         /*
 212          * It's enough to flush this one mapping.
 213          * (PGE mappings get flushed as well)
 214          */
 215         __flush_tlb_one(vaddr);
 216 }
 217
 218 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
 219 {
 220         pgd_t *pgd;
 221         pud_t *pud_page;
 222
 223         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
 224
 225         pgd = pgd_offset_k(vaddr);
 226         if (pgd_none(*pgd)) {
 227                 printk(KERN_ERR
 228                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
 229                 return;
 230         }
 231         pud_page = (pud_t*)pgd_page_vaddr(*pgd);
 232         set_pte_vaddr_pud(pud_page, vaddr, pteval);
 233 }
 234
 235 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
 236 {
 237         pgd_t *pgd;
 238         pud_t *pud;
 239
 240         pgd = pgd_offset_k(vaddr);
 241         pud = fill_pud(pgd, vaddr);
 242         return fill_pmd(pud, vaddr);
 243 }
 244
 245 pte_t * __init populate_extra_pte(unsigned long vaddr)
 246 {
 247         pmd_t *pmd;
 248
 249         pmd = populate_extra_pmd(vaddr);
 250         return fill_pte(pmd, vaddr);
 251 }
 252
 253 /*
 254  * Create large page table mappings for a range of physical addresses.
 255  */
 256 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
 257                                                 pgprot_t prot)
 258 {
 259         pgd_t *pgd;
 260         pud_t *pud;
 261         pmd_t *pmd;
 262
 263         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
 264         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
 265                 pgd = pgd_offset_k((unsigned long)__va(phys));
 266                 if (pgd_none(*pgd)) {
 267                         pud = (pud_t *) spp_getpage();
 268                         set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
 269                                                 _PAGE_USER));
 270                 }
 271                 pud = pud_offset(pgd, (unsigned long)__va(phys));
 272                 if (pud_none(*pud)) {
 273                         pmd = (pmd_t *) spp_getpage();
 274                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
 275                                                 _PAGE_USER));
 276                 }
 277                 pmd = pmd_offset(pud, phys);
 278                 BUG_ON(!pmd_none(*pmd));
 279                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
 280         }
 281 }
 282
 283 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
 284 {
 285         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
 286 }
 287
 288 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 289 {
 290         __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
 291 }
 292
 293 /*
 294  * The head.S code sets up the kernel high mapping:
 295  *
 296  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
 297  *
 298  * phys_addr holds the negative offset to the kernel, which is added
 299  * to the compile time generated pmds. This results in invalid pmds up
 300  * to the point where we hit the physaddr 0 mapping.
 301  *
 302  * We limit the mappings to the region from _text to _end.  _end is
 303  * rounded up to the 2MB boundary. This catches the invalid pmds as
 304  * well, as they are located before _text:
 305  */
 306 void __init cleanup_highmap(void)
 307 {
 308         unsigned long vaddr = __START_KERNEL_map;
 309         unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
 310         pmd_t *pmd = level2_kernel_pgt;
 311         pmd_t *last_pmd = pmd + PTRS_PER_PMD;
 312
 313         for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
 314                 if (pmd_none(*pmd))
 315                         continue;
 316                 if (vaddr < (unsigned long) _text || vaddr > end)
 317                         set_pmd(pmd, __pmd(0));
 318         }
 319 }
 320
 321 static __ref void *alloc_low_page(unsigned long *phys)
 322 {
 323         unsigned long pfn = e820_table_end++;
 324         void *adr;
 325
 326         if (after_bootmem) {
 327                 adr = (void *)get_zeroed_page(GFP_ATOMIC);
 328                 *phys = __pa(adr);
 329
 330                 return adr;
 331         }
 332
 333         if (pfn >= e820_table_top)
 334                 panic("alloc_low_page: ran out of memory");
 335
 336         adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
 337         memset(adr, 0, PAGE_SIZE);
 338         *phys  = pfn * PAGE_SIZE;
 339         return adr;
 340 }
 341
 342 static __ref void unmap_low_page(void *adr)
 343 {
 344         if (after_bootmem)
 345                 return;
 346
 347         early_iounmap(adr, PAGE_SIZE);
 348 }
 349
 350 static unsigned long __meminit
 351 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
 352               pgprot_t prot)
 353 {
 354         unsigned pages = 0;
 355         unsigned long last_map_addr = end;
 356         int i;
 357
 358         pte_t *pte = pte_page + pte_index(addr);
 359
 360         for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
 361
 362                 if (addr >= end) {
 363                         if (!after_bootmem) {
 364                                 for(; i < PTRS_PER_PTE; i++, pte++)
 365                                         set_pte(pte, __pte(0));
 366                         }
 367                         break;
 368                 }
 369
 370                 /*
 371                  * We will re-use the existing mapping.
 372                  * Xen for example has some special requirements, like mapping
 373                  * pagetable pages as RO. So assume someone who pre-setup
 374                  * these mappings are more intelligent.
 375                  */
 376                 if (pte_val(*pte)) {
 377                         pages++;
 378                         continue;
 379                 }
 380
 381                 if (0)
 382                         printk("   pte=%p addr=%lx pte=%016lx\n",
 383                                pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
 384                 pages++;
 385                 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
 386                 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
 387         }
 388
 389         update_page_count(PG_LEVEL_4K, pages);
 390
 391         return last_map_addr;
 392 }
 393
 394 static unsigned long __meminit
 395 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end,
 396                 pgprot_t prot)
 397 {
 398         pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
 399
 400         return phys_pte_init(pte, address, end, prot);
 401 }
 402
 403 static unsigned long __meminit
 404 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 405               unsigned long page_size_mask, pgprot_t prot)
 406 {
 407         unsigned long pages = 0;
 408         unsigned long last_map_addr = end;
 409
 410         int i = pmd_index(address);
 411
 412         for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
 413                 unsigned long pte_phys;
 414                 pmd_t *pmd = pmd_page + pmd_index(address);
 415                 pte_t *pte;
 416                 pgprot_t new_prot = prot;
 417
 418                 if (address >= end) {
 419                         if (!after_bootmem) {
 420                                 for (; i < PTRS_PER_PMD; i++, pmd++)
 421                                         set_pmd(pmd, __pmd(0));
 422                         }
 423                         break;
 424                 }
 425
 426                 if (pmd_val(*pmd)) {
 427                         if (!pmd_large(*pmd)) {
 428                                 spin_lock(&init_mm.page_table_lock);
 429                                 last_map_addr = phys_pte_update(pmd, address,
 430                                                                 end, prot);
 431                                 spin_unlock(&init_mm.page_table_lock);
 432                                 continue;
 433                         }
 434                         /*
 435                          * If we are ok with PG_LEVEL_2M mapping, then we will
 436                          * use the existing mapping,
 437                          *
 438                          * Otherwise, we will split the large page mapping but
 439                          * use the same existing protection bits except for
 440                          * large page, so that we don't violate Intel's TLB
 441                          * Application note (317080) which says, while changing
 442                          * the page sizes, new and old translations should
 443                          * not differ with respect to page frame and
 444                          * attributes.
 445                          */
 446                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
 447                                 pages++;
 448                                 continue;
 449                         }
 450                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
 451                 }
 452
 453                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
 454                         pages++;
 455                         spin_lock(&init_mm.page_table_lock);
 456                         set_pte((pte_t *)pmd,
 457                                 pfn_pte(address >> PAGE_SHIFT,
 458                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
 459                         spin_unlock(&init_mm.page_table_lock);
 460                         last_map_addr = (address & PMD_MASK) + PMD_SIZE;
 461                         continue;
 462                 }
 463
 464                 pte = alloc_low_page(&pte_phys);
 465                 last_map_addr = phys_pte_init(pte, address, end, new_prot);
 466                 unmap_low_page(pte);
 467
 468                 spin_lock(&init_mm.page_table_lock);
 469                 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
 470                 spin_unlock(&init_mm.page_table_lock);
 471         }
 472         update_page_count(PG_LEVEL_2M, pages);
 473         return last_map_addr;
 474 }
 475
 476 static unsigned long __meminit
 477 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
 478                 unsigned long page_size_mask, pgprot_t prot)
 479 {
 480         pmd_t *pmd = pmd_offset(pud, 0);
 481         unsigned long last_map_addr;
 482
 483         last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask, prot);
 484         __flush_tlb_all();
 485         return last_map_addr;
 486 }
 487
 488 static unsigned long __meminit
 489 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
 490                          unsigned long page_size_mask)
 491 {
 492         unsigned long pages = 0;
 493         unsigned long last_map_addr = end;
 494         int i = pud_index(addr);
 495
 496         for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
 497                 unsigned long pmd_phys;
 498                 pud_t *pud = pud_page + pud_index(addr);
 499                 pmd_t *pmd;
 500                 pgprot_t prot = PAGE_KERNEL;
 501
 502                 if (addr >= end)
 503                         break;
 504
 505                 if (!after_bootmem &&
 506                                 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
 507                         set_pud(pud, __pud(0));
 508                         continue;
 509                 }
 510
 511                 if (pud_val(*pud)) {
 512                         if (!pud_large(*pud)) {
 513                                 last_map_addr = phys_pmd_update(pud, addr, end,
 514                                                          page_size_mask, prot);
 515                                 continue;
 516                         }
 517                         /*
 518                          * If we are ok with PG_LEVEL_1G mapping, then we will
 519                          * use the existing mapping.
 520                          *
 521                          * Otherwise, we will split the gbpage mapping but use
 522                          * the same existing protection  bits except for large
 523                          * page, so that we don't violate Intel's TLB
 524                          * Application note (317080) which says, while changing
 525                          * the page sizes, new and old translations should
 526                          * not differ with respect to page frame and
 527                          * attributes.
 528                          */
 529                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
 530                                 pages++;
 531                                 continue;
 532                         }
 533                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
 534                 }
 535
 536                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
 537                         pages++;
 538                         spin_lock(&init_mm.page_table_lock);
 539                         set_pte((pte_t *)pud,
 540                                 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
 541                         spin_unlock(&init_mm.page_table_lock);
 542                         last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
 543                         continue;
 544                 }
 545
 546                 pmd = alloc_low_page(&pmd_phys);
 547                 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
 548                                               prot);
 549                 unmap_low_page(pmd);
 550
 551                 spin_lock(&init_mm.page_table_lock);
 552                 pud_populate(&init_mm, pud, __va(pmd_phys));
 553                 spin_unlock(&init_mm.page_table_lock);
 554         }
 555         __flush_tlb_all();
 556
 557         update_page_count(PG_LEVEL_1G, pages);
 558
 559         return last_map_addr;
 560 }
 561
 562 static unsigned long __meminit
 563 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
 564                  unsigned long page_size_mask)
 565 {
 566         pud_t *pud;
 567
 568         pud = (pud_t *)pgd_page_vaddr(*pgd);
 569
 570         return phys_pud_init(pud, addr, end, page_size_mask);
 571 }
 572
 573 unsigned long __init
 574 kernel_physical_mapping_init(unsigned long start,
 575                              unsigned long end,
 576                              unsigned long page_size_mask)
 577 {
 578
 579         unsigned long next, last_map_addr = end;
 580
 581         start = (unsigned long)__va(start);
 582         end = (unsigned long)__va(end);
 583
 584         for (; start < end; start = next) {
 585                 pgd_t *pgd = pgd_offset_k(start);
 586                 unsigned long pud_phys;
 587                 pud_t *pud;
 588
 589                 next = (start + PGDIR_SIZE) & PGDIR_MASK;
 590                 if (next > end)
 591                         next = end;
 592
 593                 if (pgd_val(*pgd)) {
 594                         last_map_addr = phys_pud_update(pgd, __pa(start),
 595                                                  __pa(end), page_size_mask);
 596                         continue;
 597                 }
 598
 599                 pud = alloc_low_page(&pud_phys);
 600                 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
 601                                                  page_size_mask);
 602                 unmap_low_page(pud);
 603
 604                 spin_lock(&init_mm.page_table_lock);
 605                 pgd_populate(&init_mm, pgd, __va(pud_phys));
 606                 spin_unlock(&init_mm.page_table_lock);
 607         }
 608         __flush_tlb_all();
 609
 610         return last_map_addr;
 611 }
 612
 613 #ifndef CONFIG_NUMA
 614 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
 615 {
 616         unsigned long bootmap_size, bootmap;
 617
 618         bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
 619         bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
 620                                  PAGE_SIZE);
 621         if (bootmap == -1L)
 622                 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
 623         /* don't touch min_low_pfn */
 624         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
 625                                          0, end_pfn);
 626         e820_register_active_regions(0, start_pfn, end_pfn);
 627         free_bootmem_with_active_regions(0, end_pfn);
 628         early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
 629         reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
 630 }
 631
 632 void __init paging_init(void)
 633 {
 634         unsigned long max_zone_pfns[MAX_NR_ZONES];
 635
 636         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 637         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
 638         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
 639         max_zone_pfns[ZONE_NORMAL] = max_pfn;
 640
 641         memory_present(0, 0, max_pfn);
 642         sparse_init();
 643         free_area_init_nodes(max_zone_pfns);
 644 }
 645 #endif
 646
 647 /*
 648  * Memory hotplug specific functions
 649  */
 650 #ifdef CONFIG_MEMORY_HOTPLUG
 651 /*
 652  * Memory is added always to NORMAL zone. This means you will never get
 653  * additional DMA/DMA32 memory.
 654  */
 655 int arch_add_memory(int nid, u64 start, u64 size)
 656 {
 657         struct pglist_data *pgdat = NODE_DATA(nid);
 658         struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
 659         unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
 660         unsigned long nr_pages = size >> PAGE_SHIFT;
 661         int ret;
 662
 663         last_mapped_pfn = init_memory_mapping(start, start + size);
 664         if (last_mapped_pfn > max_pfn_mapped)
 665                 max_pfn_mapped = last_mapped_pfn;
 666
 667         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 668         WARN_ON_ONCE(ret);
 669
 670         return ret;
 671 }
 672 EXPORT_SYMBOL_GPL(arch_add_memory);
 673
 674 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
 675 int memory_add_physaddr_to_nid(u64 start)
 676 {
 677         return 0;
 678 }
 679 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 680 #endif
 681
 682 #endif /* CONFIG_MEMORY_HOTPLUG */
 683
 684 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
 685                          kcore_modules, kcore_vsyscall;
 686
 687 void __init mem_init(void)
 688 {
 689         long codesize, reservedpages, datasize, initsize;
 690         unsigned long absent_pages;
 691
 692         pci_iommu_alloc();
 693
 694         /* clear_bss() already clear the empty_zero_page */
 695
 696         reservedpages = 0;
 697
 698         /* this will put all low memory onto the freelists */
 699 #ifdef CONFIG_NUMA
 700         totalram_pages = numa_free_all_bootmem();
 701 #else
 702         totalram_pages = free_all_bootmem();
 703 #endif
 704
 705         absent_pages = absent_pages_in_range(0, max_pfn);
 706         reservedpages = max_pfn - totalram_pages - absent_pages;
 707         after_bootmem = 1;
 708
 709         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 710         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 711         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 712
 713         /* Register memory areas for /proc/kcore */
 714         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 715         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 716                    VMALLOC_END-VMALLOC_START);
 717         kclist_add(&kcore_kernel, &_stext, _end - _stext);
 718         kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
 719         kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
 720                                  VSYSCALL_END - VSYSCALL_START);
 721
 722         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 723                          "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
 724                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 725                 max_pfn << (PAGE_SHIFT-10),
 726                 codesize >> 10,
 727                 absent_pages << (PAGE_SHIFT-10),
 728                 reservedpages << (PAGE_SHIFT-10),
 729                 datasize >> 10,
 730                 initsize >> 10);
 731 }
 732
 733 #ifdef CONFIG_DEBUG_RODATA
 734 const int rodata_test_data = 0xC3;
 735 EXPORT_SYMBOL_GPL(rodata_test_data);
 736
 737 static int kernel_set_to_readonly;
 738
 739 void set_kernel_text_rw(void)
 740 {
 741         unsigned long start = PFN_ALIGN(_stext);
 742         unsigned long end = PFN_ALIGN(__start_rodata);
 743
 744         if (!kernel_set_to_readonly)
 745                 return;
 746
 747         pr_debug("Set kernel text: %lx - %lx for read write\n",
 748                  start, end);
 749
 750         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
 751 }
 752
 753 void set_kernel_text_ro(void)
 754 {
 755         unsigned long start = PFN_ALIGN(_stext);
 756         unsigned long end = PFN_ALIGN(__start_rodata);
 757
 758         if (!kernel_set_to_readonly)
 759                 return;
 760
 761         pr_debug("Set kernel text: %lx - %lx for read only\n",
 762                  start, end);
 763
 764         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
 765 }
 766
 767 void mark_rodata_ro(void)
 768 {
 769         unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
 770         unsigned long rodata_start =
 771                 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
 772
 773         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
 774                (end - start) >> 10);
 775         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
 776
 777         kernel_set_to_readonly = 1;
 778
 779         /*
 780          * The rodata section (but not the kernel text!) should also be
 781          * not-executable.
 782          */
 783         set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
 784
 785         rodata_test();
 786
 787 #ifdef CONFIG_CPA_DEBUG
 788         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
 789         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
 790
 791         printk(KERN_INFO "Testing CPA: again\n");
 792         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
 793 #endif
 794 }
 795
 796 #endif
 797
 798 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
 799                                    int flags)
 800 {
 801 #ifdef CONFIG_NUMA
 802         int nid, next_nid;
 803         int ret;
 804 #endif
 805         unsigned long pfn = phys >> PAGE_SHIFT;
 806
 807         if (pfn >= max_pfn) {
 808                 /*
 809                  * This can happen with kdump kernels when accessing
 810                  * firmware tables:
 811                  */
 812                 if (pfn < max_pfn_mapped)
 813                         return -EFAULT;
 814
 815                 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
 816                                 phys, len);
 817                 return -EFAULT;
 818         }
 819
 820         /* Should check here against the e820 map to avoid double free */
 821 #ifdef CONFIG_NUMA
 822         nid = phys_to_nid(phys);
 823         next_nid = phys_to_nid(phys + len - 1);
 824         if (nid == next_nid)
 825                 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
 826         else
 827                 ret = reserve_bootmem(phys, len, flags);
 828
 829         if (ret != 0)
 830                 return ret;
 831
 832 #else
 833         reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
 834 #endif
 835
 836         if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
 837                 dma_reserve += len / PAGE_SIZE;
 838                 set_dma_reserve(dma_reserve);
 839         }
 840
 841         return 0;
 842 }
 843
 844 int kern_addr_valid(unsigned long addr)
 845 {
 846         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
 847         pgd_t *pgd;
 848         pud_t *pud;
 849         pmd_t *pmd;
 850         pte_t *pte;
 851
 852         if (above != 0 && above != -1UL)
 853                 return 0;
 854
 855         pgd = pgd_offset_k(addr);
 856         if (pgd_none(*pgd))
 857                 return 0;
 858
 859         pud = pud_offset(pgd, addr);
 860         if (pud_none(*pud))
 861                 return 0;
 862
 863         pmd = pmd_offset(pud, addr);
 864         if (pmd_none(*pmd))
 865                 return 0;
 866
 867         if (pmd_large(*pmd))
 868                 return pfn_valid(pmd_pfn(*pmd));
 869
 870         pte = pte_offset_kernel(pmd, addr);
 871         if (pte_none(*pte))
 872                 return 0;
 873
 874         return pfn_valid(pte_pfn(*pte));
 875 }
 876
 877 /*
 878  * A pseudo VMA to allow ptrace access for the vsyscall page.  This only
 879  * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
 880  * not need special handling anymore:
 881  */
 882 static struct vm_area_struct gate_vma = {
 883         .vm_start       = VSYSCALL_START,
 884         .vm_end         = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
 885         .vm_page_prot   = PAGE_READONLY_EXEC,
 886         .vm_flags       = VM_READ | VM_EXEC
 887 };
 888
 889 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 890 {
 891 #ifdef CONFIG_IA32_EMULATION
 892         if (test_tsk_thread_flag(tsk, TIF_IA32))
 893                 return NULL;
 894 #endif
 895         return &gate_vma;
 896 }
 897
 898 int in_gate_area(struct task_struct *task, unsigned long addr)
 899 {
 900         struct vm_area_struct *vma = get_gate_vma(task);
 901
 902         if (!vma)
 903                 return 0;
 904
 905         return (addr >= vma->vm_start) && (addr < vma->vm_end);
 906 }
 907
 908 /*
 909  * Use this when you have no reliable task/vma, typically from interrupt
 910  * context. It is less reliable than using the task's vma and may give
 911  * false positives:
 912  */
 913 int in_gate_area_no_task(unsigned long addr)
 914 {
 915         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
 916 }
 917
 918 const char *arch_vma_name(struct vm_area_struct *vma)
 919 {
 920         if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
 921                 return "[vdso]";
 922         if (vma == &gate_vma)
 923                 return "[vsyscall]";
 924         return NULL;
 925 }
 926
 927 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 928 /*
 929  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
 930  */
 931 static long __meminitdata addr_start, addr_end;
 932 static void __meminitdata *p_start, *p_end;
 933 static int __meminitdata node_start;
 934
 935 int __meminit
 936 vmemmap_populate(struct page *start_page, unsigned long size, int node)
 937 {
 938         unsigned long addr = (unsigned long)start_page;
 939         unsigned long end = (unsigned long)(start_page + size);
 940         unsigned long next;
 941         pgd_t *pgd;
 942         pud_t *pud;
 943         pmd_t *pmd;
 944
 945         for (; addr < end; addr = next) {
 946                 void *p = NULL;
 947
 948                 pgd = vmemmap_pgd_populate(addr, node);
 949                 if (!pgd)
 950                         return -ENOMEM;
 951
 952                 pud = vmemmap_pud_populate(pgd, addr, node);
 953                 if (!pud)
 954                         return -ENOMEM;
 955
 956                 if (!cpu_has_pse) {
 957                         next = (addr + PAGE_SIZE) & PAGE_MASK;
 958                         pmd = vmemmap_pmd_populate(pud, addr, node);
 959
 960                         if (!pmd)
 961                                 return -ENOMEM;
 962
 963                         p = vmemmap_pte_populate(pmd, addr, node);
 964
 965                         if (!p)
 966                                 return -ENOMEM;
 967
 968                         addr_end = addr + PAGE_SIZE;
 969                         p_end = p + PAGE_SIZE;
 970                 } else {
 971                         next = pmd_addr_end(addr, end);
 972
 973                         pmd = pmd_offset(pud, addr);
 974                         if (pmd_none(*pmd)) {
 975                                 pte_t entry;
 976
 977                                 p = vmemmap_alloc_block(PMD_SIZE, node);
 978                                 if (!p)
 979                                         return -ENOMEM;
 980
 981                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
 982                                                 PAGE_KERNEL_LARGE);
 983                                 set_pmd(pmd, __pmd(pte_val(entry)));
 984
 985                                 /* check to see if we have contiguous blocks */
 986                                 if (p_end != p || node_start != node) {
 987                                         if (p_start)
 988                                                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
 989                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
 990                                         addr_start = addr;
 991                                         node_start = node;
 992                                         p_start = p;
 993                                 }
 994
 995                                 addr_end = addr + PMD_SIZE;
 996                                 p_end = p + PMD_SIZE;
 997                         } else
 998                                 vmemmap_verify((pte_t *)pmd, node, addr, next);
 999                 }
1000
1001         }
1002         return 0;
1003 }
1004
1005 void __meminit vmemmap_populate_print_last(void)
1006 {
1007         if (p_start) {
1008                 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1009                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1010                 p_start = NULL;
1011                 p_end = NULL;
1012                 node_start = 0;
1013         }
1014 }
1015 #endif