arch/ia64/mm/init.c

   1 /*
   2  * Initialize MMU support.
   3  *
   4  * Copyright (C) 1998-2003 Hewlett-Packard Co
   5  *      David Mosberger-Tang <davidm@hpl.hp.com>
   6  */
   7 #include <linux/kernel.h>
   8 #include <linux/init.h>
   9
  10 #include <linux/bootmem.h>
  11 #include <linux/efi.h>
  12 #include <linux/elf.h>
  13 #include <linux/mm.h>
  14 #include <linux/mmzone.h>
  15 #include <linux/module.h>
  16 #include <linux/personality.h>
  17 #include <linux/reboot.h>
  18 #include <linux/slab.h>
  19 #include <linux/swap.h>
  20 #include <linux/proc_fs.h>
  21 #include <linux/bitops.h>
  22 #include <linux/kexec.h>
  23
  24 #include <asm/dma.h>
  25 #include <asm/io.h>
  26 #include <asm/machvec.h>
  27 #include <asm/numa.h>
  28 #include <asm/patch.h>
  29 #include <asm/pgalloc.h>
  30 #include <asm/sal.h>
  31 #include <asm/sections.h>
  32 #include <asm/system.h>
  33 #include <asm/tlb.h>
  34 #include <asm/uaccess.h>
  35 #include <asm/unistd.h>
  36 #include <asm/mca.h>
  37 #include <asm/paravirt.h>
  38
  39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  40
  41 extern void ia64_tlb_init (void);
  42
  43 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
  44
  45 #ifdef CONFIG_VIRTUAL_MEM_MAP
  46 unsigned long VMALLOC_END = VMALLOC_END_INIT;
  47 EXPORT_SYMBOL(VMALLOC_END);
  48 struct page *vmem_map;
  49 EXPORT_SYMBOL(vmem_map);
  50 #endif
  51
  52 struct page *zero_page_memmap_ptr;      /* map entry for zero page */
  53 EXPORT_SYMBOL(zero_page_memmap_ptr);
  54
  55 void
  56 __ia64_sync_icache_dcache (pte_t pte)
  57 {
  58         unsigned long addr;
  59         struct page *page;
  60
  61         page = pte_page(pte);
  62         addr = (unsigned long) page_address(page);
  63
  64         if (test_bit(PG_arch_1, &page->flags))
  65                 return;                         /* i-cache is already coherent with d-cache */
  66
  67         flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
  68         set_bit(PG_arch_1, &page->flags);       /* mark page as clean */
  69 }
  70
  71 /*
  72  * Since DMA is i-cache coherent, any (complete) pages that were written via
  73  * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
  74  * flush them when they get mapped into an executable vm-area.
  75  */
  76 void
  77 dma_mark_clean(void *addr, size_t size)
  78 {
  79         unsigned long pg_addr, end;
  80
  81         pg_addr = PAGE_ALIGN((unsigned long) addr);
  82         end = (unsigned long) addr + size;
  83         while (pg_addr + PAGE_SIZE <= end) {
  84                 struct page *page = virt_to_page(pg_addr);
  85                 set_bit(PG_arch_1, &page->flags);
  86                 pg_addr += PAGE_SIZE;
  87         }
  88 }
  89
  90 inline void
  91 ia64_set_rbs_bot (void)
  92 {
  93         unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16;
  94
  95         if (stack_size > MAX_USER_STACK_SIZE)
  96                 stack_size = MAX_USER_STACK_SIZE;
  97         current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
  98 }
  99
 100 /*
 101  * This performs some platform-dependent address space initialization.
 102  * On IA-64, we want to setup the VM area for the register backing
 103  * store (which grows upwards) and install the gateway page which is
 104  * used for signal trampolines, etc.
 105  */
 106 void
 107 ia64_init_addr_space (void)
 108 {
 109         struct vm_area_struct *vma;
 110
 111         ia64_set_rbs_bot();
 112
 113         /*
 114          * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
 115          * the problem.  When the process attempts to write to the register backing store
 116          * for the first time, it will get a SEGFAULT in this case.
 117          */
 118         vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 119         if (vma) {
 120                 vma->vm_mm = current->mm;
 121                 vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
 122                 vma->vm_end = vma->vm_start + PAGE_SIZE;
 123                 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
 124                 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 125                 down_write(&current->mm->mmap_sem);
 126                 if (insert_vm_struct(current->mm, vma)) {
 127                         up_write(&current->mm->mmap_sem);
 128                         kmem_cache_free(vm_area_cachep, vma);
 129                         return;
 130                 }
 131                 up_write(&current->mm->mmap_sem);
 132         }
 133
 134         /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
 135         if (!(current->personality & MMAP_PAGE_ZERO)) {
 136                 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 137                 if (vma) {
 138                         vma->vm_mm = current->mm;
 139                         vma->vm_end = PAGE_SIZE;
 140                         vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
 141                         vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | VM_RESERVED;
 142                         down_write(&current->mm->mmap_sem);
 143                         if (insert_vm_struct(current->mm, vma)) {
 144                                 up_write(&current->mm->mmap_sem);
 145                                 kmem_cache_free(vm_area_cachep, vma);
 146                                 return;
 147                         }
 148                         up_write(&current->mm->mmap_sem);
 149                 }
 150         }
 151 }
 152
 153 void
 154 free_initmem (void)
 155 {
 156         unsigned long addr, eaddr;
 157
 158         addr = (unsigned long) ia64_imva(__init_begin);
 159         eaddr = (unsigned long) ia64_imva(__init_end);
 160         while (addr < eaddr) {
 161                 ClearPageReserved(virt_to_page(addr));
 162                 init_page_count(virt_to_page(addr));
 163                 free_page(addr);
 164                 ++totalram_pages;
 165                 addr += PAGE_SIZE;
 166         }
 167         printk(KERN_INFO "Freeing unused kernel memory: %ldkB freed\n",
 168                (__init_end - __init_begin) >> 10);
 169 }
 170
 171 void __init
 172 free_initrd_mem (unsigned long start, unsigned long end)
 173 {
 174         struct page *page;
 175         /*
 176          * EFI uses 4KB pages while the kernel can use 4KB or bigger.
 177          * Thus EFI and the kernel may have different page sizes. It is
 178          * therefore possible to have the initrd share the same page as
 179          * the end of the kernel (given current setup).
 180          *
 181          * To avoid freeing/using the wrong page (kernel sized) we:
 182          *      - align up the beginning of initrd
 183          *      - align down the end of initrd
 184          *
 185          *  |             |
 186          *  |=============| a000
 187          *  |             |
 188          *  |             |
 189          *  |             | 9000
 190          *  |/////////////|
 191          *  |/////////////|
 192          *  |=============| 8000
 193          *  |///INITRD////|
 194          *  |/////////////|
 195          *  |/////////////| 7000
 196          *  |             |
 197          *  |KKKKKKKKKKKKK|
 198          *  |=============| 6000
 199          *  |KKKKKKKKKKKKK|
 200          *  |KKKKKKKKKKKKK|
 201          *  K=kernel using 8KB pages
 202          *
 203          * In this example, we must free page 8000 ONLY. So we must align up
 204          * initrd_start and keep initrd_end as is.
 205          */
 206         start = PAGE_ALIGN(start);
 207         end = end & PAGE_MASK;
 208
 209         if (start < end)
 210                 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
 211
 212         for (; start < end; start += PAGE_SIZE) {
 213                 if (!virt_addr_valid(start))
 214                         continue;
 215                 page = virt_to_page(start);
 216                 ClearPageReserved(page);
 217                 init_page_count(page);
 218                 free_page(start);
 219                 ++totalram_pages;
 220         }
 221 }
 222
 223 /*
 224  * This installs a clean page in the kernel's page table.
 225  */
 226 static struct page * __init
 227 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
 228 {
 229         pgd_t *pgd;
 230         pud_t *pud;
 231         pmd_t *pmd;
 232         pte_t *pte;
 233
 234         if (!PageReserved(page))
 235                 printk(KERN_ERR "put_kernel_page: page at 0x%p not in reserved memory\n",
 236                        page_address(page));
 237
 238         pgd = pgd_offset_k(address);            /* note: this is NOT pgd_offset()! */
 239
 240         {
 241                 pud = pud_alloc(&init_mm, pgd, address);
 242                 if (!pud)
 243                         goto out;
 244                 pmd = pmd_alloc(&init_mm, pud, address);
 245                 if (!pmd)
 246                         goto out;
 247                 pte = pte_alloc_kernel(pmd, address);
 248                 if (!pte)
 249                         goto out;
 250                 if (!pte_none(*pte))
 251                         goto out;
 252                 set_pte(pte, mk_pte(page, pgprot));
 253         }
 254   out:
 255         /* no need for flush_tlb */
 256         return page;
 257 }
 258
 259 static void __init
 260 setup_gate (void)
 261 {
 262         void *gate_section;
 263         struct page *page;
 264
 265         /*
 266          * Map the gate page twice: once read-only to export the ELF
 267          * headers etc. and once execute-only page to enable
 268          * privilege-promotion via "epc":
 269          */
 270         gate_section = paravirt_get_gate_section();
 271         page = virt_to_page(ia64_imva(gate_section));
 272         put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
 273 #ifdef HAVE_BUGGY_SEGREL
 274         page = virt_to_page(ia64_imva(gate_section + PAGE_SIZE));
 275         put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
 276 #else
 277         put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
 278         /* Fill in the holes (if any) with read-only zero pages: */
 279         {
 280                 unsigned long addr;
 281
 282                 for (addr = GATE_ADDR + PAGE_SIZE;
 283                      addr < GATE_ADDR + PERCPU_PAGE_SIZE;
 284                      addr += PAGE_SIZE)
 285                 {
 286                         put_kernel_page(ZERO_PAGE(0), addr,
 287                                         PAGE_READONLY);
 288                         put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
 289                                         PAGE_READONLY);
 290                 }
 291         }
 292 #endif
 293         ia64_patch_gate();
 294 }
 295
 296 void __devinit
 297 ia64_mmu_init (void *my_cpu_data)
 298 {
 299         unsigned long pta, impl_va_bits;
 300         extern void __devinit tlb_init (void);
 301
 302 #ifdef CONFIG_DISABLE_VHPT
 303 #       define VHPT_ENABLE_BIT  0
 304 #else
 305 #       define VHPT_ENABLE_BIT  1
 306 #endif
 307
 308         /*
 309          * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
 310          * address space.  The IA-64 architecture guarantees that at least 50 bits of
 311          * virtual address space are implemented but if we pick a large enough page size
 312          * (e.g., 64KB), the mapped address space is big enough that it will overlap with
 313          * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
 314          * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
 315          * problem in practice.  Alternatively, we could truncate the top of the mapped
 316          * address space to not permit mappings that would overlap with the VMLPT.
 317          * --davidm 00/12/06
 318          */
 319 #       define pte_bits                 3
 320 #       define mapped_space_bits        (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
 321         /*
 322          * The virtual page table has to cover the entire implemented address space within
 323          * a region even though not all of this space may be mappable.  The reason for
 324          * this is that the Access bit and Dirty bit fault handlers perform
 325          * non-speculative accesses to the virtual page table, so the address range of the
 326          * virtual page table itself needs to be covered by virtual page table.
 327          */
 328 #       define vmlpt_bits               (impl_va_bits - PAGE_SHIFT + pte_bits)
 329 #       define POW2(n)                  (1ULL << (n))
 330
 331         impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
 332
 333         if (impl_va_bits < 51 || impl_va_bits > 61)
 334                 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
 335         /*
 336          * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
 337          * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
 338          * the test makes sure that our mapped space doesn't overlap the
 339          * unimplemented hole in the middle of the region.
 340          */
 341         if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
 342             (mapped_space_bits > impl_va_bits - 1))
 343                 panic("Cannot build a big enough virtual-linear page table"
 344                       " to cover mapped address space.\n"
 345                       " Try using a smaller page size.\n");
 346
 347
 348         /* place the VMLPT at the end of each page-table mapped region: */
 349         pta = POW2(61) - POW2(vmlpt_bits);
 350
 351         /*
 352          * Set the (virtually mapped linear) page table address.  Bit
 353          * 8 selects between the short and long format, bits 2-7 the
 354          * size of the table, and bit 0 whether the VHPT walker is
 355          * enabled.
 356          */
 357         ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
 358
 359         ia64_tlb_init();
 360
 361 #ifdef  CONFIG_HUGETLB_PAGE
 362         ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
 363         ia64_srlz_d();
 364 #endif
 365 }
 366
 367 #ifdef CONFIG_VIRTUAL_MEM_MAP
 368 int vmemmap_find_next_valid_pfn(int node, int i)
 369 {
 370         unsigned long end_address, hole_next_pfn;
 371         unsigned long stop_address;
 372         pg_data_t *pgdat = NODE_DATA(node);
 373
 374         end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
 375         end_address = PAGE_ALIGN(end_address);
 376
 377         stop_address = (unsigned long) &vmem_map[
 378                 pgdat->node_start_pfn + pgdat->node_spanned_pages];
 379
 380         do {
 381                 pgd_t *pgd;
 382                 pud_t *pud;
 383                 pmd_t *pmd;
 384                 pte_t *pte;
 385
 386                 pgd = pgd_offset_k(end_address);
 387                 if (pgd_none(*pgd)) {
 388                         end_address += PGDIR_SIZE;
 389                         continue;
 390                 }
 391
 392                 pud = pud_offset(pgd, end_address);
 393                 if (pud_none(*pud)) {
 394                         end_address += PUD_SIZE;
 395                         continue;
 396                 }
 397
 398                 pmd = pmd_offset(pud, end_address);
 399                 if (pmd_none(*pmd)) {
 400                         end_address += PMD_SIZE;
 401                         continue;
 402                 }
 403
 404                 pte = pte_offset_kernel(pmd, end_address);
 405 retry_pte:
 406                 if (pte_none(*pte)) {
 407                         end_address += PAGE_SIZE;
 408                         pte++;
 409                         if ((end_address < stop_address) &&
 410                             (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
 411                                 goto retry_pte;
 412                         continue;
 413                 }
 414                 /* Found next valid vmem_map page */
 415                 break;
 416         } while (end_address < stop_address);
 417
 418         end_address = min(end_address, stop_address);
 419         end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
 420         hole_next_pfn = end_address / sizeof(struct page);
 421         return hole_next_pfn - pgdat->node_start_pfn;
 422 }
 423
 424 int __init create_mem_map_page_table(u64 start, u64 end, void *arg)
 425 {
 426         unsigned long address, start_page, end_page;
 427         struct page *map_start, *map_end;
 428         int node;
 429         pgd_t *pgd;
 430         pud_t *pud;
 431         pmd_t *pmd;
 432         pte_t *pte;
 433
 434         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
 435         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
 436
 437         start_page = (unsigned long) map_start & PAGE_MASK;
 438         end_page = PAGE_ALIGN((unsigned long) map_end);
 439         node = paddr_to_nid(__pa(start));
 440
 441         for (address = start_page; address < end_page; address += PAGE_SIZE) {
 442                 pgd = pgd_offset_k(address);
 443                 if (pgd_none(*pgd))
 444                         pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 445                 pud = pud_offset(pgd, address);
 446
 447                 if (pud_none(*pud))
 448                         pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 449                 pmd = pmd_offset(pud, address);
 450
 451                 if (pmd_none(*pmd))
 452                         pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 453                 pte = pte_offset_kernel(pmd, address);
 454
 455                 if (pte_none(*pte))
 456                         set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
 457                                              PAGE_KERNEL));
 458         }
 459         return 0;
 460 }
 461
 462 struct memmap_init_callback_data {
 463         struct page *start;
 464         struct page *end;
 465         int nid;
 466         unsigned long zone;
 467 };
 468
 469 static int __meminit
 470 virtual_memmap_init(u64 start, u64 end, void *arg)
 471 {
 472         struct memmap_init_callback_data *args;
 473         struct page *map_start, *map_end;
 474
 475         args = (struct memmap_init_callback_data *) arg;
 476         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
 477         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
 478
 479         if (map_start < args->start)
 480                 map_start = args->start;
 481         if (map_end > args->end)
 482                 map_end = args->end;
 483
 484         /*
 485          * We have to initialize "out of bounds" struct page elements that fit completely
 486          * on the same pages that were allocated for the "in bounds" elements because they
 487          * may be referenced later (and found to be "reserved").
 488          */
 489         map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
 490         map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
 491                     / sizeof(struct page));
 492
 493         if (map_start < map_end)
 494                 memmap_init_zone((unsigned long)(map_end - map_start),
 495                                  args->nid, args->zone, page_to_pfn(map_start),
 496                                  MEMMAP_EARLY);
 497         return 0;
 498 }
 499
 500 void __meminit
 501 memmap_init (unsigned long size, int nid, unsigned long zone,
 502              unsigned long start_pfn)
 503 {
 504         if (!vmem_map)
 505                 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
 506         else {
 507                 struct page *start;
 508                 struct memmap_init_callback_data args;
 509
 510                 start = pfn_to_page(start_pfn);
 511                 args.start = start;
 512                 args.end = start + size;
 513                 args.nid = nid;
 514                 args.zone = zone;
 515
 516                 efi_memmap_walk(virtual_memmap_init, &args);
 517         }
 518 }
 519
 520 int
 521 ia64_pfn_valid (unsigned long pfn)
 522 {
 523         char byte;
 524         struct page *pg = pfn_to_page(pfn);
 525
 526         return     (__get_user(byte, (char __user *) pg) == 0)
 527                 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
 528                         || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
 529 }
 530 EXPORT_SYMBOL(ia64_pfn_valid);
 531
 532 int __init find_largest_hole(u64 start, u64 end, void *arg)
 533 {
 534         u64 *max_gap = arg;
 535
 536         static u64 last_end = PAGE_OFFSET;
 537
 538         /* NOTE: this algorithm assumes efi memmap table is ordered */
 539
 540         if (*max_gap < (start - last_end))
 541                 *max_gap = start - last_end;
 542         last_end = end;
 543         return 0;
 544 }
 545
 546 #endif /* CONFIG_VIRTUAL_MEM_MAP */
 547
 548 int __init register_active_ranges(u64 start, u64 len, int nid)
 549 {
 550         u64 end = start + len;
 551
 552 #ifdef CONFIG_KEXEC
 553         if (start > crashk_res.start && start < crashk_res.end)
 554                 start = crashk_res.end;
 555         if (end > crashk_res.start && end < crashk_res.end)
 556                 end = crashk_res.start;
 557 #endif
 558
 559         if (start < end)
 560                 add_active_range(nid, __pa(start) >> PAGE_SHIFT,
 561                         __pa(end) >> PAGE_SHIFT);
 562         return 0;
 563 }
 564
 565 static int __init
 566 count_reserved_pages(u64 start, u64 end, void *arg)
 567 {
 568         unsigned long num_reserved = 0;
 569         unsigned long *count = arg;
 570
 571         for (; start < end; start += PAGE_SIZE)
 572                 if (PageReserved(virt_to_page(start)))
 573                         ++num_reserved;
 574         *count += num_reserved;
 575         return 0;
 576 }
 577
 578 int
 579 find_max_min_low_pfn (u64 start, u64 end, void *arg)
 580 {
 581         unsigned long pfn_start, pfn_end;
 582 #ifdef CONFIG_FLATMEM
 583         pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
 584         pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
 585 #else
 586         pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
 587         pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
 588 #endif
 589         min_low_pfn = min(min_low_pfn, pfn_start);
 590         max_low_pfn = max(max_low_pfn, pfn_end);
 591         return 0;
 592 }
 593
 594 /*
 595  * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
 596  * system call handler.  When this option is in effect, all fsyscalls will end up bubbling
 597  * down into the kernel and calling the normal (heavy-weight) syscall handler.  This is
 598  * useful for performance testing, but conceivably could also come in handy for debugging
 599  * purposes.
 600  */
 601
 602 static int nolwsys __initdata;
 603
 604 static int __init
 605 nolwsys_setup (char *s)
 606 {
 607         nolwsys = 1;
 608         return 1;
 609 }
 610
 611 __setup("nolwsys", nolwsys_setup);
 612
 613 void __init
 614 mem_init (void)
 615 {
 616         long reserved_pages, codesize, datasize, initsize;
 617         pg_data_t *pgdat;
 618         int i;
 619
 620         BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
 621         BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
 622         BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
 623
 624 #ifdef CONFIG_PCI
 625         /*
 626          * This needs to be called _after_ the command line has been parsed but _before_
 627          * any drivers that may need the PCI DMA interface are initialized or bootmem has
 628          * been freed.
 629          */
 630         platform_dma_init();
 631 #endif
 632
 633 #ifdef CONFIG_FLATMEM
 634         BUG_ON(!mem_map);
 635         max_mapnr = max_low_pfn;
 636 #endif
 637
 638         high_memory = __va(max_low_pfn * PAGE_SIZE);
 639
 640         for_each_online_pgdat(pgdat)
 641                 if (pgdat->bdata->node_bootmem_map)
 642                         totalram_pages += free_all_bootmem_node(pgdat);
 643
 644         reserved_pages = 0;
 645         efi_memmap_walk(count_reserved_pages, &reserved_pages);
 646
 647         codesize =  (unsigned long) _etext - (unsigned long) _stext;
 648         datasize =  (unsigned long) _edata - (unsigned long) _etext;
 649         initsize =  (unsigned long) __init_end - (unsigned long) __init_begin;
 650
 651         printk(KERN_INFO "Memory: %luk/%luk available (%luk code, %luk reserved, "
 652                "%luk data, %luk init)\n", nr_free_pages() << (PAGE_SHIFT - 10),
 653                num_physpages << (PAGE_SHIFT - 10), codesize >> 10,
 654                reserved_pages << (PAGE_SHIFT - 10), datasize >> 10, initsize >> 10);
 655
 656
 657         /*
 658          * For fsyscall entrpoints with no light-weight handler, use the ordinary
 659          * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
 660          * code can tell them apart.
 661          */
 662         for (i = 0; i < NR_syscalls; ++i) {
 663                 extern unsigned long sys_call_table[NR_syscalls];
 664                 unsigned long *fsyscall_table = paravirt_get_fsyscall_table();
 665
 666                 if (!fsyscall_table[i] || nolwsys)
 667                         fsyscall_table[i] = sys_call_table[i] | 1;
 668         }
 669         setup_gate();
 670 }
 671
 672 #ifdef CONFIG_MEMORY_HOTPLUG
 673 int arch_add_memory(int nid, u64 start, u64 size)
 674 {
 675         pg_data_t *pgdat;
 676         struct zone *zone;
 677         unsigned long start_pfn = start >> PAGE_SHIFT;
 678         unsigned long nr_pages = size >> PAGE_SHIFT;
 679         int ret;
 680
 681         pgdat = NODE_DATA(nid);
 682
 683         zone = pgdat->node_zones + ZONE_NORMAL;
 684         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 685
 686         if (ret)
 687                 printk("%s: Problem encountered in __add_pages() as ret=%d\n",
 688                        __func__,  ret);
 689
 690         return ret;
 691 }
 692 #endif
 693
 694 /*
 695  * Even when CONFIG_IA32_SUPPORT is not enabled it is
 696  * useful to have the Linux/x86 domain registered to
 697  * avoid an attempted module load when emulators call
 698  * personality(PER_LINUX32). This saves several milliseconds
 699  * on each such call.
 700  */
 701 static struct exec_domain ia32_exec_domain;
 702
 703 static int __init
 704 per_linux32_init(void)
 705 {
 706         ia32_exec_domain.name = "Linux/x86";
 707         ia32_exec_domain.handler = NULL;
 708         ia32_exec_domain.pers_low = PER_LINUX32;
 709         ia32_exec_domain.pers_high = PER_LINUX32;
 710         ia32_exec_domain.signal_map = default_exec_domain.signal_map;
 711         ia32_exec_domain.signal_invmap = default_exec_domain.signal_invmap;
 712         register_exec_domain(&ia32_exec_domain);
 713
 714         return 0;
 715 }
 716
 717 __initcall(per_linux32_init);