arch/ia64/mm/init.c

   1 /*
   2  * Initialize MMU support.
   3  *
   4  * Copyright (C) 1998-2002 Hewlett-Packard Co
   5  *      David Mosberger-Tang <davidm@hpl.hp.com>
   6  */
   7 #include <linux/config.h>
   8 #include <linux/module.h>
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11
  12 #include <linux/bootmem.h>
  13 #include <linux/mm.h>
  14 #include <linux/personality.h>
  15 #include <linux/reboot.h>
  16 #include <linux/slab.h>
  17 #include <linux/swap.h>
  18 #include <linux/efi.h>
  19 #include <linux/mmzone.h>
  20
  21 #include <asm/bitops.h>
  22 #include <asm/dma.h>
  23 #include <asm/ia32.h>
  24 #include <asm/io.h>
  25 #include <asm/machvec.h>
  26 #include <asm/numa.h>
  27 #include <asm/pgalloc.h>
  28 #include <asm/sal.h>
  29 #include <asm/system.h>
  30 #include <asm/uaccess.h>
  31 #include <asm/mca.h>
  32
  33 /* References to section boundaries: */
  34 extern char _stext, _etext, _edata, __init_begin, __init_end;
  35
  36 extern void ia64_tlb_init (void);
  37 extern int  filter_rsvd_memory (unsigned long, unsigned long, void *);
  38
  39 /* Note - may be changed by platform_setup */
  40 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
  41 #define LARGE_GAP 0x40000000 /* Use virtual mem map if a hole is > than this */
  42
  43 static unsigned long totalram_pages, reserved_pages;
  44 struct page *zero_page_memmap_ptr;              /* map entry for zero page */
  45
  46 unsigned long vmalloc_end = VMALLOC_END_INIT;
  47
  48 static struct page *vmem_map;
  49 static unsigned long num_dma_physpages;
  50
  51 int
  52 do_check_pgt_cache (int low, int high)
  53 {
  54         int freed = 0;
  55
  56         if (pgtable_cache_size > high) {
  57                 do {
  58                         if (pgd_quicklist)
  59                                 free_page((unsigned long)pgd_alloc_one_fast(0)), ++freed;
  60                         if (pmd_quicklist)
  61                                 free_page((unsigned long)pmd_alloc_one_fast(0, 0)), ++freed;
  62                         if (pte_quicklist)
  63                                 free_page((unsigned long)pte_alloc_one_fast(0, 0)), ++freed;
  64                 } while (pgtable_cache_size > low);
  65         }
  66         return freed;
  67 }
  68
  69 inline void
  70 ia64_set_rbs_bot (void)
  71 {
  72         unsigned long stack_size = current->rlim[RLIMIT_STACK].rlim_max & -16;
  73
  74         if (stack_size > MAX_USER_STACK_SIZE)
  75                 stack_size = MAX_USER_STACK_SIZE;
  76         current->thread.rbs_bot = STACK_TOP - stack_size;
  77 }
  78
  79 /*
  80  * This performs some platform-dependent address space initialization.
  81  * On IA-64, we want to setup the VM area for the register backing
  82  * store (which grows upwards) and install the gateway page which is
  83  * used for signal trampolines, etc.
  84  */
  85 void
  86 ia64_init_addr_space (void)
  87 {
  88         struct vm_area_struct *vma;
  89
  90         ia64_set_rbs_bot();
  91
  92         /*
  93          * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
  94          * the problem.  When the process attempts to write to the register backing store
  95          * for the first time, it will get a SEGFAULT in this case.
  96          */
  97         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
  98         if (vma) {
  99                 vma->vm_mm = current->mm;
 100                 vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
 101                 vma->vm_end = vma->vm_start + PAGE_SIZE;
 102                 vma->vm_page_prot = PAGE_COPY;
 103                 vma->vm_flags = VM_READ|VM_WRITE|VM_MAYREAD|VM_MAYWRITE|VM_GROWSUP;
 104                 vma->vm_ops = NULL;
 105                 vma->vm_pgoff = 0;
 106                 vma->vm_file = NULL;
 107                 vma->vm_private_data = NULL;
 108                 down_write(&current->mm->mmap_sem);
 109                 if (insert_vm_struct(current->mm, vma)) {
 110                         up_write(&current->mm->mmap_sem);
 111                         kmem_cache_free(vm_area_cachep, vma);
 112                         return;
 113                 }
 114                 up_write(&current->mm->mmap_sem);
 115         }
 116
 117         /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
 118         if (!(current->personality & MMAP_PAGE_ZERO)) {
 119                 vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
 120                 if (vma) {
 121                         memset(vma, 0, sizeof(*vma));
 122                         vma->vm_mm = current->mm;
 123                         vma->vm_end = PAGE_SIZE;
 124                         vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
 125                         vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | VM_RESERVED;
 126                         down_write(&current->mm->mmap_sem);
 127                         if (insert_vm_struct(current->mm, vma)) {
 128                                 up_write(&current->mm->mmap_sem);
 129                                 kmem_cache_free(vm_area_cachep, vma);
 130                                 return;
 131                         }
 132                         up_write(&current->mm->mmap_sem);
 133                 }
 134         }
 135 }
 136
 137 void
 138 free_initmem (void)
 139 {
 140         unsigned long addr, eaddr;
 141
 142         addr = (unsigned long) ia64_imva(&__init_begin);
 143         eaddr = (unsigned long) ia64_imva(&__init_end);
 144         for (; addr < eaddr; addr += PAGE_SIZE) {
 145                 clear_bit(PG_reserved, &virt_to_page((void *)addr)->flags);
 146                 set_page_count(virt_to_page((void *)addr), 1);
 147                 free_page(addr);
 148                 ++totalram_pages;
 149         }
 150         printk(KERN_INFO "Freeing unused kernel memory: %ldkB freed\n",
 151                 (&__init_end - &__init_begin) >> 10);
 152 }
 153
 154 void
 155 free_initrd_mem(unsigned long start, unsigned long end)
 156 {
 157         /*
 158          * EFI uses 4KB pages while the kernel can use 4KB  or bigger.
 159          * Thus EFI and the kernel may have different page sizes. It is
 160          * therefore possible to have the initrd share the same page as
 161          * the end of the kernel (given current setup).
 162          *
 163          * To avoid freeing/using the wrong page (kernel sized) we:
 164          *      - align up the beginning of initrd
 165          *      - align down the end of initrd
 166          *
 167          *  |             |
 168          *  |=============| a000
 169          *  |             |
 170          *  |             |
 171          *  |             | 9000
 172          *  |/////////////|
 173          *  |/////////////|
 174          *  |=============| 8000
 175          *  |///INITRD////|
 176          *  |/////////////|
 177          *  |/////////////| 7000
 178          *  |             |
 179          *  |KKKKKKKKKKKKK|
 180          *  |=============| 6000
 181          *  |KKKKKKKKKKKKK|
 182          *  |KKKKKKKKKKKKK|
 183          *  K=kernel using 8KB pages
 184          *
 185          * In this example, we must free page 8000 ONLY. So we must align up
 186          * initrd_start and keep initrd_end as is.
 187          */
 188         start = PAGE_ALIGN(start);
 189         end = end & PAGE_MASK;
 190
 191         if (start < end)
 192                 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
 193
 194         for (; start < end; start += PAGE_SIZE) {
 195                 if (!VALID_PAGE(virt_to_page((void *)start)))
 196                         continue;
 197                 clear_bit(PG_reserved, &virt_to_page((void *)start)->flags);
 198                 set_page_count(virt_to_page((void *)start), 1);
 199                 free_page(start);
 200                 ++totalram_pages;
 201         }
 202 }
 203
 204 void
 205 si_meminfo (struct sysinfo *val)
 206 {
 207         val->totalram = totalram_pages;
 208         val->sharedram = 0;
 209         val->freeram = nr_free_pages();
 210         val->bufferram = atomic_read(&buffermem_pages);
 211         val->totalhigh = 0;
 212         val->freehigh = 0;
 213         val->mem_unit = PAGE_SIZE;
 214         return;
 215 }
 216
 217 void
 218 show_mem(void)
 219 {
 220         int i, reserved;
 221         int shared, cached;
 222         pg_data_t *pgdat;
 223         char *tchar = (numnodes > 1) ? "\t" : "";
 224
 225         printk("Mem-info:\n");
 226         show_free_areas();
 227
 228         printk("Free swap:       %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
 229         for_each_pgdat(pgdat) {
 230                 reserved=0;
 231                 cached=0;
 232                 shared=0;
 233                 if (numnodes > 1)
 234                         printk("Node ID: %d\n", pgdat->node_id);
 235                 for(i = 0; i < pgdat->node_size; i++) {
 236                         if (!VALID_PAGE(pgdat->node_mem_map+i))
 237                                 continue;
 238                         if (PageReserved(pgdat->node_mem_map+i))
 239                                 reserved++;
 240                         else if (PageSwapCache(pgdat->node_mem_map+i))
 241                                 cached++;
 242                         else if (page_count(pgdat->node_mem_map + i))
 243                                 shared += page_count(pgdat->node_mem_map + i) - 1;
 244                 }
 245                 printk("%s%ld pages of RAM\n", tchar, pgdat->node_size);
 246                 printk("%s%d reserved pages\n", tchar, reserved);
 247                 printk("%s%d pages shared\n", tchar, shared);
 248                 printk("%s%d pages swap cached\n", tchar, cached);
 249         }
 250         printk("Total of %ld pages in page table cache\n", pgtable_cache_size);
 251         show_buffers();
 252         printk("%d free buffer pages\n", nr_free_buffer_pages());
 253 }
 254
 255 /*
 256  * This is like put_dirty_page() but installs a clean page with PAGE_GATE protection
 257  * (execute-only, typically).
 258  */
 259 struct page *
 260 put_gate_page (struct page *page, unsigned long address)
 261 {
 262         pgd_t *pgd;
 263         pmd_t *pmd;
 264         pte_t *pte;
 265
 266         if (!PageReserved(page))
 267                 printk(KERN_ERR "put_gate_page: gate page at 0x%p not in reserved memory\n",
 268                        page_address(page));
 269
 270         pgd = pgd_offset_k(address);            /* note: this is NOT pgd_offset()! */
 271
 272         spin_lock(&init_mm.page_table_lock);
 273         {
 274                 pmd = pmd_alloc(&init_mm, pgd, address);
 275                 if (!pmd)
 276                         goto out;
 277                 pte = pte_alloc(&init_mm, pmd, address);
 278                 if (!pte)
 279                         goto out;
 280                 if (!pte_none(*pte)) {
 281                         pte_ERROR(*pte);
 282                         goto out;
 283                 }
 284                 flush_page_to_ram(page);
 285                 set_pte(pte, mk_pte(page, PAGE_GATE));
 286         }
 287   out:  spin_unlock(&init_mm.page_table_lock);
 288         /* no need for flush_tlb */
 289         return page;
 290 }
 291
 292 void __init
 293 ia64_mmu_init (void *my_cpu_data)
 294 {
 295         unsigned long psr, rid, pta, impl_va_bits;
 296         extern void __init tlb_init (void);
 297 #ifdef CONFIG_IA64_MCA
 298         int cpu;
 299 #endif
 300
 301 #ifdef CONFIG_DISABLE_VHPT
 302 #       define VHPT_ENABLE_BIT  0
 303 #else
 304 #       define VHPT_ENABLE_BIT  1
 305 #endif
 306
 307         /*
 308          * Set up the kernel identity mapping for regions 6 and 5.  The mapping for region
 309          * 7 is setup up in _start().
 310          */
 311         psr = ia64_clear_ic();
 312
 313         rid = ia64_rid(IA64_REGION_ID_KERNEL, __IA64_UNCACHED_OFFSET);
 314         ia64_set_rr(__IA64_UNCACHED_OFFSET, (rid << 8) | (IA64_GRANULE_SHIFT << 2));
 315
 316         rid = ia64_rid(IA64_REGION_ID_KERNEL, VMALLOC_START);
 317         ia64_set_rr(VMALLOC_START, (rid << 8) | (PAGE_SHIFT << 2) | 1);
 318
 319         /* ensure rr6 is up-to-date before inserting the PERCPU_ADDR translation: */
 320         ia64_srlz_d();
 321
 322         ia64_itr(0x2, IA64_TR_PERCPU_DATA, PERCPU_ADDR,
 323                  pte_val(mk_pte_phys(__pa(my_cpu_data), PAGE_KERNEL)), PAGE_SHIFT);
 324
 325         ia64_set_psr(psr);
 326         ia64_srlz_i();
 327
 328         /*
 329          * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
 330          * address space.  The IA-64 architecture guarantees that at least 50 bits of
 331          * virtual address space are implemented but if we pick a large enough page size
 332          * (e.g., 64KB), the mapped address space is big enough that it will overlap with
 333          * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
 334          * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
 335          * problem in practice.  Alternatively, we could truncate the top of the mapped
 336          * address space to not permit mappings that would overlap with the VMLPT.
 337          * --davidm 00/12/06
 338          */
 339 #       define pte_bits                 3
 340 #       define mapped_space_bits        (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
 341         /*
 342          * The virtual page table has to cover the entire implemented address space within
 343          * a region even though not all of this space may be mappable.  The reason for
 344          * this is that the Access bit and Dirty bit fault handlers perform
 345          * non-speculative accesses to the virtual page table, so the address range of the
 346          * virtual page table itself needs to be covered by virtual page table.
 347          */
 348 #       define vmlpt_bits               (impl_va_bits - PAGE_SHIFT + pte_bits)
 349 #       define POW2(n)                  (1ULL << (n))
 350
 351         impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
 352
 353         if (impl_va_bits < 51 || impl_va_bits > 61)
 354                 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
 355
 356         /* place the VMLPT at the end of each page-table mapped region: */
 357         pta = POW2(61) - POW2(vmlpt_bits);
 358
 359         if (POW2(mapped_space_bits) >= pta)
 360                 panic("mm/init: overlap between virtually mapped linear page table and "
 361                       "mapped kernel space!");
 362         /*
 363          * Set the (virtually mapped linear) page table address.  Bit
 364          * 8 selects between the short and long format, bits 2-7 the
 365          * size of the table, and bit 0 whether the VHPT walker is
 366          * enabled.
 367          */
 368         ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
 369
 370         ia64_tlb_init();
 371
 372 #ifdef  CONFIG_IA64_MCA
 373         cpu = smp_processor_id();
 374
 375         /* mca handler uses cr.lid as key to pick the right entry */
 376         ia64_mca_tlb_list[cpu].cr_lid = ia64_get_lid();
 377
 378         /* insert this percpu data information into our list for MCA recovery purposes */
 379         ia64_mca_tlb_list[cpu].percpu_paddr = pte_val(mk_pte_phys(__pa(my_cpu_data), PAGE_KERNEL));
 380         /* Also save per-cpu tlb flush recipe for use in physical mode mca handler */
 381         ia64_mca_tlb_list[cpu].ptce_base = local_cpu_data->ptce_base;
 382         ia64_mca_tlb_list[cpu].ptce_count[0] = local_cpu_data->ptce_count[0];
 383         ia64_mca_tlb_list[cpu].ptce_count[1] = local_cpu_data->ptce_count[1];
 384         ia64_mca_tlb_list[cpu].ptce_stride[0] = local_cpu_data->ptce_stride[0];
 385         ia64_mca_tlb_list[cpu].ptce_stride[1] = local_cpu_data->ptce_stride[1];
 386 #endif
 387 }
 388
 389 static int
 390 create_mem_map_page_table (u64 start, u64 end, void *arg)
 391 {
 392         unsigned long address, start_page, end_page, next_blk_page;
 393         unsigned long blk_start;
 394         struct page *map_start, *map_end;
 395         int node=0;
 396         pgd_t *pgd;
 397         pmd_t *pmd;
 398         pte_t *pte;
 399
 400         /* should we use platform_map_nr here? */
 401
 402         map_start = vmem_map + MAP_NR_DENSE(start);
 403         map_end   = vmem_map + MAP_NR_DENSE(end);
 404
 405         start_page = (unsigned long) map_start & PAGE_MASK;
 406         end_page = PAGE_ALIGN((unsigned long) map_end);
 407
 408         /* force the first iteration to get node id */
 409         blk_start = start;
 410         next_blk_page = 0;
 411
 412         for (address = start_page; address < end_page; address += PAGE_SIZE) {
 413
 414                 /* if we went across a node boundary, get new nid */
 415                 if (address >= next_blk_page) {
 416                         struct page *map_next_blk;
 417
 418                         node = paddr_to_nid(__pa(blk_start));
 419
 420                         /* get end addr of this memblk as next blk_start */
 421                         blk_start = (unsigned long) __va(min(end, memblk_endpaddr(__pa(blk_start))));
 422                         map_next_blk = vmem_map + MAP_NR_DENSE(blk_start);
 423                         next_blk_page = PAGE_ALIGN((unsigned long) map_next_blk);
 424                 }
 425
 426                 pgd = pgd_offset_k(address);
 427                 if (pgd_none(*pgd))
 428                         pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 429                 pmd = pmd_offset(pgd, address);
 430
 431                 if (pmd_none(*pmd))
 432                         pmd_populate(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
 433                 pte = pte_offset(pmd, address);
 434
 435                 if (pte_none(*pte))
 436                         set_pte(pte, mk_pte_phys(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)),
 437                                                  PAGE_KERNEL));
 438         }
 439         return 0;
 440 }
 441
 442 struct memmap_init_callback_data {
 443         memmap_init_callback_t *memmap_init;
 444         struct page *start;
 445         struct page *end;
 446         int zone;
 447         int highmem;
 448 };
 449
 450 struct memmap_count_callback_data {
 451         int node;
 452         unsigned long num_physpages;
 453         unsigned long num_dma_physpages;
 454         unsigned long min_pfn;
 455         unsigned long max_pfn;
 456 } cdata;
 457
 458 static int
 459 virtual_memmap_init (u64 start, u64 end, void *arg)
 460 {
 461         struct memmap_init_callback_data *args;
 462         struct page *map_start, *map_end;
 463
 464         args = (struct memmap_init_callback_data *) arg;
 465
 466         /* Should we use platform_map_nr here? */
 467
 468         map_start = mem_map + MAP_NR_DENSE(start);
 469         map_end   = mem_map + MAP_NR_DENSE(end);
 470
 471         if (map_start < args->start)
 472                 map_start = args->start;
 473         if (map_end > args->end)
 474                 map_end = args->end;
 475
 476         /*
 477          * We have to initialize "out of bounds" struct page elements
 478          * that fit completely on the same pages that were allocated
 479          * for the "in bounds" elements because they may be referenced
 480          * later (and found to be "reserved").
 481          */
 482         map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1))
 483                         / sizeof(struct page);
 484         map_end += ((PAGE_ALIGN((unsigned long) map_end) -
 485                                 (unsigned long) map_end)
 486                         / sizeof(struct page));
 487
 488         if (map_start < map_end)
 489                 (*args->memmap_init)(map_start, map_end, args->zone,
 490                                      page_to_phys(map_start), args->highmem);
 491
 492         return 0;
 493 }
 494
 495 unsigned long
 496 arch_memmap_init (memmap_init_callback_t *memmap_init, struct page *start,
 497         struct page *end, int zone, unsigned long start_paddr, int highmem)
 498 {
 499         if (!vmem_map)
 500                 memmap_init(start,end,zone,page_to_phys(start),highmem);
 501         else {
 502                 struct memmap_init_callback_data args;
 503
 504                 args.memmap_init = memmap_init;
 505                 args.start = start;
 506                 args.end = end;
 507                 args.zone = zone;
 508                 args.highmem = highmem;
 509
 510                 efi_memmap_walk(virtual_memmap_init, &args);
 511         }
 512
 513         return page_to_phys(end-1) + PAGE_SIZE;;
 514 }
 515
 516 int
 517 ia64_page_valid (struct page *page)
 518 {
 519         char byte;
 520
 521         return     (__get_user(byte, (char *) page) == 0)
 522                 && (__get_user(byte, (char *) (page + 1) - 1) == 0);
 523 }
 524
 525 #define GRANULEROUNDDOWN(n) ((n) & ~(IA64_GRANULE_SIZE-1))
 526 #define GRANULEROUNDUP(n) (((n)+IA64_GRANULE_SIZE-1) & ~(IA64_GRANULE_SIZE-1))
 527 #define ORDERROUNDDOWN(n) ((n) & ~((PAGE_SIZE<<MAX_ORDER)-1))
 528 static int
 529 count_pages (u64 start, u64 end, int node)
 530 {
 531         start = __pa(start);
 532         end = __pa(end);
 533         if (node == cdata.node) {
 534                 cdata.num_physpages += (end - start) >> PAGE_SHIFT;
 535                 if (start <= __pa(MAX_DMA_ADDRESS))
 536                         cdata.num_dma_physpages += (min(end, __pa(MAX_DMA_ADDRESS)) - start) >> PAGE_SHIFT;
 537                 start = GRANULEROUNDDOWN(__pa(start));
 538                 start = ORDERROUNDDOWN(start);
 539                 end = GRANULEROUNDUP(__pa(end));
 540                 cdata.max_pfn = max(cdata.max_pfn, end >> PAGE_SHIFT);
 541                 cdata.min_pfn = min(cdata.min_pfn, start >> PAGE_SHIFT);
 542         }
 543         return 0;
 544 }
 545
 546 static int
 547 find_largest_hole(u64 start, u64 end, void *arg)
 548 {
 549         u64 *max_gap = arg;
 550         static u64 last_end = PAGE_OFFSET;
 551
 552         /* NOTE: this algorithm assumes efi memmap table is ordered */
 553
 554         if (*max_gap < (start - last_end))
 555                 *max_gap = start - last_end;
 556         last_end = end;
 557         return 0;
 558 }
 559
 560 /*
 561  * Set up the page tables.
 562  */
 563 void
 564 paging_init (void)
 565 {
 566         unsigned long max_dma;
 567         unsigned long zones_size[MAX_NR_ZONES];
 568         unsigned long zholes_size[MAX_NR_ZONES];
 569         unsigned long max_gap;
 570         int node;
 571
 572         /* initialize mem_map[] */
 573
 574         max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 575         max_gap = 0;
 576         efi_memmap_walk(find_largest_hole, (u64 *)&max_gap);
 577
 578         for (node=0; node < numnodes; node++) {
 579                 memset(zones_size, 0, sizeof(zones_size));
 580                 memset(zholes_size, 0, sizeof(zholes_size));
 581                 memset(&cdata, 0, sizeof(cdata));
 582
 583                 cdata.node = node;
 584                 cdata.min_pfn = ~0;
 585
 586                 efi_memmap_walk(filter_rsvd_memory, count_pages);
 587                 num_dma_physpages += cdata.num_dma_physpages;
 588                 num_physpages += cdata.num_physpages;
 589
 590                 if (cdata.min_pfn >= max_dma) {
 591                         zones_size[ZONE_NORMAL] = cdata.max_pfn - cdata.min_pfn;
 592                         zholes_size[ZONE_NORMAL] = cdata.max_pfn - cdata.min_pfn - cdata.num_physpages;
 593                 } else if (cdata.max_pfn < max_dma) {
 594                         zones_size[ZONE_DMA] = cdata.max_pfn - cdata.min_pfn;
 595                         zholes_size[ZONE_DMA] = cdata.max_pfn - cdata.min_pfn - cdata.num_dma_physpages;
 596                 } else {
 597                         zones_size[ZONE_DMA] = max_dma - cdata.min_pfn;
 598                         zholes_size[ZONE_DMA] = zones_size[ZONE_DMA] - cdata.num_dma_physpages;
 599                         zones_size[ZONE_NORMAL] = cdata.max_pfn - max_dma;
 600                         zholes_size[ZONE_NORMAL] = zones_size[ZONE_NORMAL] - (cdata.num_physpages - cdata.num_dma_physpages);
 601                 }
 602
 603                 if (numnodes == 1 && max_gap < LARGE_GAP) {
 604                         vmem_map = (struct page *)0;
 605                         zones_size[ZONE_DMA] += cdata.min_pfn;
 606                         zholes_size[ZONE_DMA] += cdata.min_pfn;
 607                         free_area_init_core(0, NODE_DATA(node), &mem_map, zones_size, 0, zholes_size, NULL);
 608                 } else {
 609
 610                         /* allocate virtual mem_map */
 611
 612                         if (node == 0) {
 613                                 unsigned long map_size;
 614                                 map_size = PAGE_ALIGN(max_low_pfn*sizeof(struct page));
 615                                 vmalloc_end -= map_size;
 616                                 mem_map = vmem_map = (struct page *) vmalloc_end;
 617                                 efi_memmap_walk(create_mem_map_page_table, 0);
 618                                 printk(KERN_INFO "Virtual mem_map starts at 0x%p\n", mem_map);
 619                         }
 620
 621                         free_area_init_node(node, NODE_DATA(node), vmem_map+cdata.min_pfn, zones_size,
 622                                 cdata.min_pfn<<PAGE_SHIFT, zholes_size);
 623                 }
 624         }
 625
 626         zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
 627 }
 628
 629 static int
 630 count_reserved_pages (u64 start, u64 end, void *arg)
 631 {
 632         unsigned long num_reserved = 0;
 633         struct page *pg;
 634
 635         for (pg = virt_to_page((void *)start); pg < virt_to_page((void *)end); ++pg)
 636                 if (PageReserved(pg))
 637                         ++num_reserved;
 638         reserved_pages += num_reserved;
 639         return 0;
 640 }
 641
 642 void
 643 mem_init (void)
 644 {
 645         extern char __start_gate_section[];
 646         long codesize, datasize, initsize;
 647         unsigned long num_pgt_pages;
 648         pg_data_t *pgdat;
 649
 650
 651 #ifdef CONFIG_PCI
 652         /*
 653          * This needs to be called _after_ the command line has been parsed but _before_
 654          * any drivers that may need the PCI DMA interface are initialized or bootmem has
 655          * been freed.
 656          */
 657         platform_pci_dma_init();
 658 #endif
 659
 660         if (!mem_map)
 661                 BUG();
 662
 663         max_mapnr = max_low_pfn;
 664         high_memory = __va(max_low_pfn * PAGE_SIZE);
 665
 666         for_each_pgdat(pgdat)
 667                 totalram_pages += free_all_bootmem_node(pgdat);
 668
 669         reserved_pages = 0;
 670         efi_memmap_walk(filter_rsvd_memory, count_reserved_pages);
 671
 672         codesize =  (unsigned long) &_etext - (unsigned long) &_stext;
 673         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 674         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 675
 676         printk(KERN_INFO "Memory: %luk/%luk available (%luk code, %luk reserved, %luk data, %luk init)\n",
 677                (unsigned long) nr_free_pages() << (PAGE_SHIFT - 10),
 678                num_physpages << (PAGE_SHIFT - 10), codesize >> 10,
 679                reserved_pages << (PAGE_SHIFT - 10), datasize >> 10, initsize >> 10);
 680
 681         /*
 682          * Allow for enough (cached) page table pages so that we can map the entire memory
 683          * at least once.  Each task also needs a couple of page tables pages, so add in a
 684          * fudge factor for that (don't use "threads-max" here; that would be wrong!).
 685          * Don't allow the cache to be more than 10% of total memory, though.
 686          */
 687 #       define NUM_TASKS        500     /* typical number of tasks */
 688         num_pgt_pages = nr_free_pages() / PTRS_PER_PGD + NUM_TASKS;
 689         if (num_pgt_pages > nr_free_pages() / 10)
 690                 num_pgt_pages = nr_free_pages() / 10;
 691         if (num_pgt_pages > pgt_cache_water[1])
 692                 pgt_cache_water[1] = num_pgt_pages;
 693
 694         /* install the gate page in the global page table: */
 695         put_gate_page(virt_to_page(ia64_imva(__start_gate_section)), GATE_ADDR);
 696
 697 #ifdef CONFIG_IA32_SUPPORT
 698         ia32_gdt_init();
 699 #endif
 700 }