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/memblock.h>
  14 #include <linux/mm.h>
  15 #include <linux/mmzone.h>
  16 #include <linux/module.h>
  17 #include <linux/personality.h>
  18 #include <linux/reboot.h>
  19 #include <linux/slab.h>
  20 #include <linux/swap.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/bitops.h>
  23 #include <linux/kexec.h>
  24
  25 #include <asm/dma.h>
  26 #include <asm/io.h>
  27 #include <asm/machvec.h>
  28 #include <asm/numa.h>
  29 #include <asm/patch.h>
  30 #include <asm/pgalloc.h>
  31 #include <asm/sal.h>
  32 #include <asm/sections.h>
  33 #include <asm/tlb.h>
  34 #include <asm/uaccess.h>
  35 #include <asm/unistd.h>
  36 #include <asm/mca.h>
  37
  38 extern void ia64_tlb_init (void);
  39
  40 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
  41
  42 #ifdef CONFIG_VIRTUAL_MEM_MAP
  43 unsigned long VMALLOC_END = VMALLOC_END_INIT;
  44 EXPORT_SYMBOL(VMALLOC_END);
  45 struct page *vmem_map;
  46 EXPORT_SYMBOL(vmem_map);
  47 #endif
  48
  49 struct page *zero_page_memmap_ptr;      /* map entry for zero page */
  50 EXPORT_SYMBOL(zero_page_memmap_ptr);
  51
  52 void
  53 __ia64_sync_icache_dcache (pte_t pte)
  54 {
  55         unsigned long addr;
  56         struct page *page;
  57
  58         page = pte_page(pte);
  59         addr = (unsigned long) page_address(page);
  60
  61         if (test_bit(PG_arch_1, &page->flags))
  62                 return;                         /* i-cache is already coherent with d-cache */
  63
  64         flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
  65         set_bit(PG_arch_1, &page->flags);       /* mark page as clean */
  66 }
  67
  68 /*
  69  * Since DMA is i-cache coherent, any (complete) pages that were written via
  70  * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
  71  * flush them when they get mapped into an executable vm-area.
  72  */
  73 void
  74 dma_mark_clean(void *addr, size_t size)
  75 {
  76         unsigned long pg_addr, end;
  77
  78         pg_addr = PAGE_ALIGN((unsigned long) addr);
  79         end = (unsigned long) addr + size;
  80         while (pg_addr + PAGE_SIZE <= end) {
  81                 struct page *page = virt_to_page(pg_addr);
  82                 set_bit(PG_arch_1, &page->flags);
  83                 pg_addr += PAGE_SIZE;
  84         }
  85 }
  86
  87 inline void
  88 ia64_set_rbs_bot (void)
  89 {
  90         unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16;
  91
  92         if (stack_size > MAX_USER_STACK_SIZE)
  93                 stack_size = MAX_USER_STACK_SIZE;
  94         current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
  95 }
  96
  97 /*
  98  * This performs some platform-dependent address space initialization.
  99  * On IA-64, we want to setup the VM area for the register backing
 100  * store (which grows upwards) and install the gateway page which is
 101  * used for signal trampolines, etc.
 102  */
 103 void
 104 ia64_init_addr_space (void)
 105 {
 106         struct vm_area_struct *vma;
 107
 108         ia64_set_rbs_bot();
 109
 110         /*
 111          * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
 112          * the problem.  When the process attempts to write to the register backing store
 113          * for the first time, it will get a SEGFAULT in this case.
 114          */
 115         vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 116         if (vma) {
 117                 INIT_LIST_HEAD(&vma->anon_vma_chain);
 118                 vma->vm_mm = current->mm;
 119                 vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
 120                 vma->vm_end = vma->vm_start + PAGE_SIZE;
 121                 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
 122                 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 123                 down_write(&current->mm->mmap_sem);
 124                 if (insert_vm_struct(current->mm, vma)) {
 125                         up_write(&current->mm->mmap_sem);
 126                         kmem_cache_free(vm_area_cachep, vma);
 127                         return;
 128                 }
 129                 up_write(&current->mm->mmap_sem);
 130         }
 131
 132         /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
 133         if (!(current->personality & MMAP_PAGE_ZERO)) {
 134                 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 135                 if (vma) {
 136                         INIT_LIST_HEAD(&vma->anon_vma_chain);
 137                         vma->vm_mm = current->mm;
 138                         vma->vm_end = PAGE_SIZE;
 139                         vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
 140                         vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO |
 141                                         VM_DONTEXPAND | VM_DONTDUMP;
 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         free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end),
 157                            -1, "unused kernel");
 158 }
 159
 160 void __init
 161 free_initrd_mem (unsigned long start, unsigned long end)
 162 {
 163         /*
 164          * EFI uses 4KB pages while the kernel can use 4KB or bigger.
 165          * Thus EFI and the kernel may have different page sizes. It is
 166          * therefore possible to have the initrd share the same page as
 167          * the end of the kernel (given current setup).
 168          *
 169          * To avoid freeing/using the wrong page (kernel sized) we:
 170          *      - align up the beginning of initrd
 171          *      - align down the end of initrd
 172          *
 173          *  |             |
 174          *  |=============| a000
 175          *  |             |
 176          *  |             |
 177          *  |             | 9000
 178          *  |/////////////|
 179          *  |/////////////|
 180          *  |=============| 8000
 181          *  |///INITRD////|
 182          *  |/////////////|
 183          *  |/////////////| 7000
 184          *  |             |
 185          *  |KKKKKKKKKKKKK|
 186          *  |=============| 6000
 187          *  |KKKKKKKKKKKKK|
 188          *  |KKKKKKKKKKKKK|
 189          *  K=kernel using 8KB pages
 190          *
 191          * In this example, we must free page 8000 ONLY. So we must align up
 192          * initrd_start and keep initrd_end as is.
 193          */
 194         start = PAGE_ALIGN(start);
 195         end = end & PAGE_MASK;
 196
 197         if (start < end)
 198                 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
 199
 200         for (; start < end; start += PAGE_SIZE) {
 201                 if (!virt_addr_valid(start))
 202                         continue;
 203                 free_reserved_page(virt_to_page(start));
 204         }
 205 }
 206
 207 /*
 208  * This installs a clean page in the kernel's page table.
 209  */
 210 static struct page * __init
 211 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
 212 {
 213         pgd_t *pgd;
 214         pud_t *pud;
 215         pmd_t *pmd;
 216         pte_t *pte;
 217
 218         if (!PageReserved(page))
 219                 printk(KERN_ERR "put_kernel_page: page at 0x%p not in reserved memory\n",
 220                        page_address(page));
 221
 222         pgd = pgd_offset_k(address);            /* note: this is NOT pgd_offset()! */
 223
 224         {
 225                 pud = pud_alloc(&init_mm, pgd, address);
 226                 if (!pud)
 227                         goto out;
 228                 pmd = pmd_alloc(&init_mm, pud, address);
 229                 if (!pmd)
 230                         goto out;
 231                 pte = pte_alloc_kernel(pmd, address);
 232                 if (!pte)
 233                         goto out;
 234                 if (!pte_none(*pte))
 235                         goto out;
 236                 set_pte(pte, mk_pte(page, pgprot));
 237         }
 238   out:
 239         /* no need for flush_tlb */
 240         return page;
 241 }
 242
 243 static void __init
 244 setup_gate (void)
 245 {
 246         struct page *page;
 247
 248         /*
 249          * Map the gate page twice: once read-only to export the ELF
 250          * headers etc. and once execute-only page to enable
 251          * privilege-promotion via "epc":
 252          */
 253         page = virt_to_page(ia64_imva(__start_gate_section));
 254         put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
 255 #ifdef HAVE_BUGGY_SEGREL
 256         page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE));
 257         put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
 258 #else
 259         put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
 260         /* Fill in the holes (if any) with read-only zero pages: */
 261         {
 262                 unsigned long addr;
 263
 264                 for (addr = GATE_ADDR + PAGE_SIZE;
 265                      addr < GATE_ADDR + PERCPU_PAGE_SIZE;
 266                      addr += PAGE_SIZE)
 267                 {
 268                         put_kernel_page(ZERO_PAGE(0), addr,
 269                                         PAGE_READONLY);
 270                         put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
 271                                         PAGE_READONLY);
 272                 }
 273         }
 274 #endif
 275         ia64_patch_gate();
 276 }
 277
 278 static struct vm_area_struct gate_vma;
 279
 280 static int __init gate_vma_init(void)
 281 {
 282         gate_vma.vm_mm = NULL;
 283         gate_vma.vm_start = FIXADDR_USER_START;
 284         gate_vma.vm_end = FIXADDR_USER_END;
 285         gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
 286         gate_vma.vm_page_prot = __P101;
 287
 288         return 0;
 289 }
 290 __initcall(gate_vma_init);
 291
 292 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
 293 {
 294         return &gate_vma;
 295 }
 296
 297 int in_gate_area_no_mm(unsigned long addr)
 298 {
 299         if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
 300                 return 1;
 301         return 0;
 302 }
 303
 304 int in_gate_area(struct mm_struct *mm, unsigned long addr)
 305 {
 306         return in_gate_area_no_mm(addr);
 307 }
 308
 309 void ia64_mmu_init(void *my_cpu_data)
 310 {
 311         unsigned long pta, impl_va_bits;
 312         extern void tlb_init(void);
 313
 314 #ifdef CONFIG_DISABLE_VHPT
 315 #       define VHPT_ENABLE_BIT  0
 316 #else
 317 #       define VHPT_ENABLE_BIT  1
 318 #endif
 319
 320         /*
 321          * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
 322          * address space.  The IA-64 architecture guarantees that at least 50 bits of
 323          * virtual address space are implemented but if we pick a large enough page size
 324          * (e.g., 64KB), the mapped address space is big enough that it will overlap with
 325          * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
 326          * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
 327          * problem in practice.  Alternatively, we could truncate the top of the mapped
 328          * address space to not permit mappings that would overlap with the VMLPT.
 329          * --davidm 00/12/06
 330          */
 331 #       define pte_bits                 3
 332 #       define mapped_space_bits        (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
 333         /*
 334          * The virtual page table has to cover the entire implemented address space within
 335          * a region even though not all of this space may be mappable.  The reason for
 336          * this is that the Access bit and Dirty bit fault handlers perform
 337          * non-speculative accesses to the virtual page table, so the address range of the
 338          * virtual page table itself needs to be covered by virtual page table.
 339          */
 340 #       define vmlpt_bits               (impl_va_bits - PAGE_SHIFT + pte_bits)
 341 #       define POW2(n)                  (1ULL << (n))
 342
 343         impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
 344
 345         if (impl_va_bits < 51 || impl_va_bits > 61)
 346                 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
 347         /*
 348          * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
 349          * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
 350          * the test makes sure that our mapped space doesn't overlap the
 351          * unimplemented hole in the middle of the region.
 352          */
 353         if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
 354             (mapped_space_bits > impl_va_bits - 1))
 355                 panic("Cannot build a big enough virtual-linear page table"
 356                       " to cover mapped address space.\n"
 357                       " Try using a smaller page size.\n");
 358
 359
 360         /* place the VMLPT at the end of each page-table mapped region: */
 361         pta = POW2(61) - POW2(vmlpt_bits);
 362
 363         /*
 364          * Set the (virtually mapped linear) page table address.  Bit
 365          * 8 selects between the short and long format, bits 2-7 the
 366          * size of the table, and bit 0 whether the VHPT walker is
 367          * enabled.
 368          */
 369         ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
 370
 371         ia64_tlb_init();
 372
 373 #ifdef  CONFIG_HUGETLB_PAGE
 374         ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
 375         ia64_srlz_d();
 376 #endif
 377 }
 378
 379 #ifdef CONFIG_VIRTUAL_MEM_MAP
 380 int vmemmap_find_next_valid_pfn(int node, int i)
 381 {
 382         unsigned long end_address, hole_next_pfn;
 383         unsigned long stop_address;
 384         pg_data_t *pgdat = NODE_DATA(node);
 385
 386         end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
 387         end_address = PAGE_ALIGN(end_address);
 388         stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)];
 389
 390         do {
 391                 pgd_t *pgd;
 392                 pud_t *pud;
 393                 pmd_t *pmd;
 394                 pte_t *pte;
 395
 396                 pgd = pgd_offset_k(end_address);
 397                 if (pgd_none(*pgd)) {
 398                         end_address += PGDIR_SIZE;
 399                         continue;
 400                 }
 401
 402                 pud = pud_offset(pgd, end_address);
 403                 if (pud_none(*pud)) {
 404                         end_address += PUD_SIZE;
 405                         continue;
 406                 }
 407
 408                 pmd = pmd_offset(pud, end_address);
 409                 if (pmd_none(*pmd)) {
 410                         end_address += PMD_SIZE;
 411                         continue;
 412                 }
 413
 414                 pte = pte_offset_kernel(pmd, end_address);
 415 retry_pte:
 416                 if (pte_none(*pte)) {
 417                         end_address += PAGE_SIZE;
 418                         pte++;
 419                         if ((end_address < stop_address) &&
 420                             (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
 421                                 goto retry_pte;
 422                         continue;
 423                 }
 424                 /* Found next valid vmem_map page */
 425                 break;
 426         } while (end_address < stop_address);
 427
 428         end_address = min(end_address, stop_address);
 429         end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
 430         hole_next_pfn = end_address / sizeof(struct page);
 431         return hole_next_pfn - pgdat->node_start_pfn;
 432 }
 433
 434 int __init create_mem_map_page_table(u64 start, u64 end, void *arg)
 435 {
 436         unsigned long address, start_page, end_page;
 437         struct page *map_start, *map_end;
 438         int node;
 439         pgd_t *pgd;
 440         pud_t *pud;
 441         pmd_t *pmd;
 442         pte_t *pte;
 443
 444         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
 445         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
 446
 447         start_page = (unsigned long) map_start & PAGE_MASK;
 448         end_page = PAGE_ALIGN((unsigned long) map_end);
 449         node = paddr_to_nid(__pa(start));
 450
 451         for (address = start_page; address < end_page; address += PAGE_SIZE) {
 452                 pgd = pgd_offset_k(address);
 453                 if (pgd_none(*pgd))
 454                         pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 455                 pud = pud_offset(pgd, address);
 456
 457                 if (pud_none(*pud))
 458                         pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 459                 pmd = pmd_offset(pud, address);
 460
 461                 if (pmd_none(*pmd))
 462                         pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 463                 pte = pte_offset_kernel(pmd, address);
 464
 465                 if (pte_none(*pte))
 466                         set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
 467                                              PAGE_KERNEL));
 468         }
 469         return 0;
 470 }
 471
 472 struct memmap_init_callback_data {
 473         struct page *start;
 474         struct page *end;
 475         int nid;
 476         unsigned long zone;
 477 };
 478
 479 static int __meminit
 480 virtual_memmap_init(u64 start, u64 end, void *arg)
 481 {
 482         struct memmap_init_callback_data *args;
 483         struct page *map_start, *map_end;
 484
 485         args = (struct memmap_init_callback_data *) arg;
 486         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
 487         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
 488
 489         if (map_start < args->start)
 490                 map_start = args->start;
 491         if (map_end > args->end)
 492                 map_end = args->end;
 493
 494         /*
 495          * We have to initialize "out of bounds" struct page elements that fit completely
 496          * on the same pages that were allocated for the "in bounds" elements because they
 497          * may be referenced later (and found to be "reserved").
 498          */
 499         map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
 500         map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
 501                     / sizeof(struct page));
 502
 503         if (map_start < map_end)
 504                 memmap_init_zone((unsigned long)(map_end - map_start),
 505                                  args->nid, args->zone, page_to_pfn(map_start),
 506                                  MEMMAP_EARLY);
 507         return 0;
 508 }
 509
 510 void __meminit
 511 memmap_init (unsigned long size, int nid, unsigned long zone,
 512              unsigned long start_pfn)
 513 {
 514         if (!vmem_map)
 515                 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
 516         else {
 517                 struct page *start;
 518                 struct memmap_init_callback_data args;
 519
 520                 start = pfn_to_page(start_pfn);
 521                 args.start = start;
 522                 args.end = start + size;
 523                 args.nid = nid;
 524                 args.zone = zone;
 525
 526                 efi_memmap_walk(virtual_memmap_init, &args);
 527         }
 528 }
 529
 530 int
 531 ia64_pfn_valid (unsigned long pfn)
 532 {
 533         char byte;
 534         struct page *pg = pfn_to_page(pfn);
 535
 536         return     (__get_user(byte, (char __user *) pg) == 0)
 537                 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
 538                         || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
 539 }
 540 EXPORT_SYMBOL(ia64_pfn_valid);
 541
 542 int __init find_largest_hole(u64 start, u64 end, void *arg)
 543 {
 544         u64 *max_gap = arg;
 545
 546         static u64 last_end = PAGE_OFFSET;
 547
 548         /* NOTE: this algorithm assumes efi memmap table is ordered */
 549
 550         if (*max_gap < (start - last_end))
 551                 *max_gap = start - last_end;
 552         last_end = end;
 553         return 0;
 554 }
 555
 556 #endif /* CONFIG_VIRTUAL_MEM_MAP */
 557
 558 int __init register_active_ranges(u64 start, u64 len, int nid)
 559 {
 560         u64 end = start + len;
 561
 562 #ifdef CONFIG_KEXEC
 563         if (start > crashk_res.start && start < crashk_res.end)
 564                 start = crashk_res.end;
 565         if (end > crashk_res.start && end < crashk_res.end)
 566                 end = crashk_res.start;
 567 #endif
 568
 569         if (start < end)
 570                 memblock_add_node(__pa(start), end - start, nid);
 571         return 0;
 572 }
 573
 574 int
 575 find_max_min_low_pfn (u64 start, u64 end, void *arg)
 576 {
 577         unsigned long pfn_start, pfn_end;
 578 #ifdef CONFIG_FLATMEM
 579         pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
 580         pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
 581 #else
 582         pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
 583         pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
 584 #endif
 585         min_low_pfn = min(min_low_pfn, pfn_start);
 586         max_low_pfn = max(max_low_pfn, pfn_end);
 587         return 0;
 588 }
 589
 590 /*
 591  * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
 592  * system call handler.  When this option is in effect, all fsyscalls will end up bubbling
 593  * down into the kernel and calling the normal (heavy-weight) syscall handler.  This is
 594  * useful for performance testing, but conceivably could also come in handy for debugging
 595  * purposes.
 596  */
 597
 598 static int nolwsys __initdata;
 599
 600 static int __init
 601 nolwsys_setup (char *s)
 602 {
 603         nolwsys = 1;
 604         return 1;
 605 }
 606
 607 __setup("nolwsys", nolwsys_setup);
 608
 609 void __init
 610 mem_init (void)
 611 {
 612         int i;
 613
 614         BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
 615         BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
 616         BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
 617
 618 #ifdef CONFIG_PCI
 619         /*
 620          * This needs to be called _after_ the command line has been parsed but _before_
 621          * any drivers that may need the PCI DMA interface are initialized or bootmem has
 622          * been freed.
 623          */
 624         platform_dma_init();
 625 #endif
 626
 627 #ifdef CONFIG_FLATMEM
 628         BUG_ON(!mem_map);
 629 #endif
 630
 631         set_max_mapnr(max_low_pfn);
 632         high_memory = __va(max_low_pfn * PAGE_SIZE);
 633         free_all_bootmem();
 634         mem_init_print_info(NULL);
 635
 636         /*
 637          * For fsyscall entrpoints with no light-weight handler, use the ordinary
 638          * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
 639          * code can tell them apart.
 640          */
 641         for (i = 0; i < NR_syscalls; ++i) {
 642                 extern unsigned long fsyscall_table[NR_syscalls];
 643                 extern unsigned long sys_call_table[NR_syscalls];
 644
 645                 if (!fsyscall_table[i] || nolwsys)
 646                         fsyscall_table[i] = sys_call_table[i] | 1;
 647         }
 648         setup_gate();
 649 }
 650
 651 #ifdef CONFIG_MEMORY_HOTPLUG
 652 int arch_add_memory(int nid, u64 start, u64 size)
 653 {
 654         pg_data_t *pgdat;
 655         struct zone *zone;
 656         unsigned long start_pfn = start >> PAGE_SHIFT;
 657         unsigned long nr_pages = size >> PAGE_SHIFT;
 658         int ret;
 659
 660         pgdat = NODE_DATA(nid);
 661
 662         zone = pgdat->node_zones +
 663                 zone_for_memory(nid, start, size, ZONE_NORMAL);
 664         ret = __add_pages(nid, zone, start_pfn, nr_pages);
 665
 666         if (ret)
 667                 printk("%s: Problem encountered in __add_pages() as ret=%d\n",
 668                        __func__,  ret);
 669
 670         return ret;
 671 }
 672
 673 #ifdef CONFIG_MEMORY_HOTREMOVE
 674 int arch_remove_memory(u64 start, u64 size)
 675 {
 676         unsigned long start_pfn = start >> PAGE_SHIFT;
 677         unsigned long nr_pages = size >> PAGE_SHIFT;
 678         struct zone *zone;
 679         int ret;
 680
 681         zone = page_zone(pfn_to_page(start_pfn));
 682         ret = __remove_pages(zone, start_pfn, nr_pages);
 683         if (ret)
 684                 pr_warn("%s: Problem encountered in __remove_pages() as"
 685                         " ret=%d\n", __func__,  ret);
 686
 687         return ret;
 688 }
 689 #endif
 690 #endif
 691
 692 /**
 693  * show_mem - give short summary of memory stats
 694  *
 695  * Shows a simple page count of reserved and used pages in the system.
 696  * For discontig machines, it does this on a per-pgdat basis.
 697  */
 698 void show_mem(unsigned int filter)
 699 {
 700         int total_reserved = 0;
 701         unsigned long total_present = 0;
 702         pg_data_t *pgdat;
 703
 704         printk(KERN_INFO "Mem-info:\n");
 705         show_free_areas(filter);
 706         printk(KERN_INFO "Node memory in pages:\n");
 707         for_each_online_pgdat(pgdat) {
 708                 unsigned long present;
 709                 unsigned long flags;
 710                 int reserved = 0;
 711                 int nid = pgdat->node_id;
 712                 int zoneid;
 713
 714                 if (skip_free_areas_node(filter, nid))
 715                         continue;
 716                 pgdat_resize_lock(pgdat, &flags);
 717
 718                 for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
 719                         struct zone *zone = &pgdat->node_zones[zoneid];
 720                         if (!populated_zone(zone))
 721                                 continue;
 722
 723                         reserved += zone->present_pages - zone->managed_pages;
 724                 }
 725                 present = pgdat->node_present_pages;
 726
 727                 pgdat_resize_unlock(pgdat, &flags);
 728                 total_present += present;
 729                 total_reserved += reserved;
 730                 printk(KERN_INFO "Node %4d:  RAM: %11ld, rsvd: %8d, ",
 731                        nid, present, reserved);
 732         }
 733         printk(KERN_INFO "%ld pages of RAM\n", total_present);
 734         printk(KERN_INFO "%d reserved pages\n", total_reserved);
 735         printk(KERN_INFO "Total of %ld pages in page table cache\n",
 736                quicklist_total_size());
 737         printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages());
 738 }