arch/powerpc/kernel/vdso.c

   1 /*
   2  *  linux/arch/ppc64/kernel/vdso.c
   3  *
   4  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
   5  *                       <benh@kernel.crashing.org>
   6  *
   7  *  This program is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU General Public License
   9  *  as published by the Free Software Foundation; either version
  10  *  2 of the License, or (at your option) any later version.
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/module.h>
  15 #include <linux/errno.h>
  16 #include <linux/sched.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mm.h>
  19 #include <linux/smp.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/stddef.h>
  22 #include <linux/unistd.h>
  23 #include <linux/slab.h>
  24 #include <linux/user.h>
  25 #include <linux/elf.h>
  26 #include <linux/security.h>
  27 #include <linux/bootmem.h>
  28
  29 #include <asm/pgtable.h>
  30 #include <asm/system.h>
  31 #include <asm/processor.h>
  32 #include <asm/mmu.h>
  33 #include <asm/mmu_context.h>
  34 #include <asm/lmb.h>
  35 #include <asm/machdep.h>
  36 #include <asm/cputable.h>
  37 #include <asm/sections.h>
  38 #include <asm/vdso.h>
  39 #include <asm/vdso_datapage.h>
  40
  41 #undef DEBUG
  42
  43 #ifdef DEBUG
  44 #define DBG(fmt...) printk(fmt)
  45 #else
  46 #define DBG(fmt...)
  47 #endif
  48
  49 /* Max supported size for symbol names */
  50 #define MAX_SYMNAME     64
  51
  52 extern char vdso32_start, vdso32_end;
  53 static void *vdso32_kbase = &vdso32_start;
  54 unsigned int vdso32_pages;
  55 unsigned long vdso32_sigtramp;
  56 unsigned long vdso32_rt_sigtramp;
  57
  58 #ifdef CONFIG_PPC64
  59 extern char vdso64_start, vdso64_end;
  60 static void *vdso64_kbase = &vdso64_start;
  61 unsigned int vdso64_pages;
  62 unsigned long vdso64_rt_sigtramp;
  63 #endif /* CONFIG_PPC64 */
  64
  65 /*
  66  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  67  * Once the early boot kernel code no longer needs to muck around
  68  * with it, it will become dynamically allocated
  69  */
  70 static union {
  71         struct vdso_data        data;
  72         u8                      page[PAGE_SIZE];
  73 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  74 struct vdso_data *vdso_data = &vdso_data_store.data;
  75
  76 /* Format of the patch table */
  77 struct vdso_patch_def
  78 {
  79         unsigned long   ftr_mask, ftr_value;
  80         const char      *gen_name;
  81         const char      *fix_name;
  82 };
  83
  84 /* Table of functions to patch based on the CPU type/revision
  85  *
  86  * Currently, we only change sync_dicache to do nothing on processors
  87  * with a coherent icache
  88  */
  89 static struct vdso_patch_def vdso_patches[] = {
  90         {
  91                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  92                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  93         },
  94         {
  95                 CPU_FTR_USE_TB, 0,
  96                 "__kernel_gettimeofday", NULL
  97         },
  98 };
  99
 100 /*
 101  * Some infos carried around for each of them during parsing at
 102  * boot time.
 103  */
 104 struct lib32_elfinfo
 105 {
 106         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 107         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 108         unsigned long   dynsymsize;     /* size of .dynsym section */
 109         char            *dynstr;        /* ptr to .dynstr section */
 110         unsigned long   text;           /* offset of .text section in .so */
 111 };
 112
 113 struct lib64_elfinfo
 114 {
 115         Elf64_Ehdr      *hdr;
 116         Elf64_Sym       *dynsym;
 117         unsigned long   dynsymsize;
 118         char            *dynstr;
 119         unsigned long   text;
 120 };
 121
 122
 123 #ifdef __DEBUG
 124 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 125 {
 126         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 127                page_count(pg),
 128                pg->flags);
 129         if (upg/* && pg != upg*/) {
 130                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 131                                                        << PAGE_SHIFT),
 132                        page_count(upg),
 133                        upg->flags);
 134         }
 135         printk("\n");
 136 }
 137
 138 static void dump_vdso_pages(struct vm_area_struct * vma)
 139 {
 140         int i;
 141
 142         if (!vma || test_thread_flag(TIF_32BIT)) {
 143                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 144                 for (i=0; i<vdso32_pages; i++) {
 145                         struct page *pg = virt_to_page(vdso32_kbase +
 146                                                        i*PAGE_SIZE);
 147                         struct page *upg = (vma && vma->vm_mm) ?
 148                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 149                                 : NULL;
 150                         dump_one_vdso_page(pg, upg);
 151                 }
 152         }
 153         if (!vma || !test_thread_flag(TIF_32BIT)) {
 154                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 155                 for (i=0; i<vdso64_pages; i++) {
 156                         struct page *pg = virt_to_page(vdso64_kbase +
 157                                                        i*PAGE_SIZE);
 158                         struct page *upg = (vma && vma->vm_mm) ?
 159                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 160                                 : NULL;
 161                         dump_one_vdso_page(pg, upg);
 162                 }
 163         }
 164 }
 165 #endif /* DEBUG */
 166
 167 /*
 168  * Keep a dummy vma_close for now, it will prevent VMA merging.
 169  */
 170 static void vdso_vma_close(struct vm_area_struct * vma)
 171 {
 172 }
 173
 174 /*
 175  * Our nopage() function, maps in the actual vDSO kernel pages, they will
 176  * be mapped read-only by do_no_page(), and eventually COW'ed, either
 177  * right away for an initial write access, or by do_wp_page().
 178  */
 179 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 180                                      unsigned long address, int *type)
 181 {
 182         unsigned long offset = address - vma->vm_start;
 183         struct page *pg;
 184 #ifdef CONFIG_PPC64
 185         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
 186                 vdso64_kbase : vdso32_kbase;
 187 #else
 188         void *vbase = vdso32_kbase;
 189 #endif
 190
 191         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
 192             current->comm, address, offset);
 193
 194         if (address < vma->vm_start || address > vma->vm_end)
 195                 return NOPAGE_SIGBUS;
 196
 197         /*
 198          * Last page is systemcfg.
 199          */
 200         if ((vma->vm_end - address) <= PAGE_SIZE)
 201                 pg = virt_to_page(vdso_data);
 202         else
 203                 pg = virt_to_page(vbase + offset);
 204
 205         get_page(pg);
 206         DBG(" ->page count: %d\n", page_count(pg));
 207
 208         return pg;
 209 }
 210
 211 static struct vm_operations_struct vdso_vmops = {
 212         .close  = vdso_vma_close,
 213         .nopage = vdso_vma_nopage,
 214 };
 215
 216 /*
 217  * This is called from binfmt_elf, we create the special vma for the
 218  * vDSO and insert it into the mm struct tree
 219  */
 220 int arch_setup_additional_pages(struct linux_binprm *bprm,
 221                                 int executable_stack)
 222 {
 223         struct mm_struct *mm = current->mm;
 224         struct vm_area_struct *vma;
 225         unsigned long vdso_pages;
 226         unsigned long vdso_base;
 227
 228 #ifdef CONFIG_PPC64
 229         if (test_thread_flag(TIF_32BIT)) {
 230                 vdso_pages = vdso32_pages;
 231                 vdso_base = VDSO32_MBASE;
 232         } else {
 233                 vdso_pages = vdso64_pages;
 234                 vdso_base = VDSO64_MBASE;
 235         }
 236 #else
 237         vdso_pages = vdso32_pages;
 238         vdso_base = VDSO32_MBASE;
 239 #endif
 240
 241         current->thread.vdso_base = 0;
 242
 243         /* vDSO has a problem and was disabled, just don't "enable" it for the
 244          * process
 245          */
 246         if (vdso_pages == 0)
 247                 return 0;
 248
 249         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
 250         if (vma == NULL)
 251                 return -ENOMEM;
 252
 253         memset(vma, 0, sizeof(*vma));
 254
 255         /* Add a page to the vdso size for the data page */
 256         vdso_pages ++;
 257
 258         /*
 259          * pick a base address for the vDSO in process space. We try to put it
 260          * at vdso_base which is the "natural" base for it, but we might fail
 261          * and end up putting it elsewhere.
 262          */
 263         vdso_base = get_unmapped_area(NULL, vdso_base,
 264                                       vdso_pages << PAGE_SHIFT, 0, 0);
 265         if (vdso_base & ~PAGE_MASK) {
 266                 kmem_cache_free(vm_area_cachep, vma);
 267                 return (int)vdso_base;
 268         }
 269
 270         current->thread.vdso_base = vdso_base;
 271
 272         vma->vm_mm = mm;
 273         vma->vm_start = current->thread.vdso_base;
 274         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 275
 276         /*
 277          * our vma flags don't have VM_WRITE so by default, the process isn't
 278          * allowed to write those pages.
 279          * gdb can break that with ptrace interface, and thus trigger COW on
 280          * those pages but it's then your responsibility to never do that on
 281          * the "data" page of the vDSO or you'll stop getting kernel updates
 282          * and your nice userland gettimeofday will be totally dead.
 283          * It's fine to use that for setting breakpoints in the vDSO code
 284          * pages though
 285          */
 286         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 287         vma->vm_flags |= mm->def_flags;
 288         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 289         vma->vm_ops = &vdso_vmops;
 290
 291         down_write(&mm->mmap_sem);
 292         if (insert_vm_struct(mm, vma)) {
 293                 up_write(&mm->mmap_sem);
 294                 kmem_cache_free(vm_area_cachep, vma);
 295                 return -ENOMEM;
 296         }
 297         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 298         up_write(&mm->mmap_sem);
 299
 300         return 0;
 301 }
 302
 303 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 304                                   unsigned long *size)
 305 {
 306         Elf32_Shdr *sechdrs;
 307         unsigned int i;
 308         char *secnames;
 309
 310         /* Grab section headers and strings so we can tell who is who */
 311         sechdrs = (void *)ehdr + ehdr->e_shoff;
 312         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 313
 314         /* Find the section they want */
 315         for (i = 1; i < ehdr->e_shnum; i++) {
 316                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 317                         if (size)
 318                                 *size = sechdrs[i].sh_size;
 319                         return (void *)ehdr + sechdrs[i].sh_offset;
 320                 }
 321         }
 322         *size = 0;
 323         return NULL;
 324 }
 325
 326 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 327                                         const char *symname)
 328 {
 329         unsigned int i;
 330         char name[MAX_SYMNAME], *c;
 331
 332         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 333                 if (lib->dynsym[i].st_name == 0)
 334                         continue;
 335                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 336                         MAX_SYMNAME);
 337                 c = strchr(name, '@');
 338                 if (c)
 339                         *c = 0;
 340                 if (strcmp(symname, name) == 0)
 341                         return &lib->dynsym[i];
 342         }
 343         return NULL;
 344 }
 345
 346 /* Note that we assume the section is .text and the symbol is relative to
 347  * the library base
 348  */
 349 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 350                                             const char *symname)
 351 {
 352         Elf32_Sym *sym = find_symbol32(lib, symname);
 353
 354         if (sym == NULL) {
 355                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 356                        symname);
 357                 return 0;
 358         }
 359         return sym->st_value - VDSO32_LBASE;
 360 }
 361
 362 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 363                                 struct lib64_elfinfo *v64,
 364                                 const char *orig, const char *fix)
 365 {
 366         Elf32_Sym *sym32_gen, *sym32_fix;
 367
 368         sym32_gen = find_symbol32(v32, orig);
 369         if (sym32_gen == NULL) {
 370                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 371                 return -1;
 372         }
 373         if (fix == NULL) {
 374                 sym32_gen->st_name = 0;
 375                 return 0;
 376         }
 377         sym32_fix = find_symbol32(v32, fix);
 378         if (sym32_fix == NULL) {
 379                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 380                 return -1;
 381         }
 382         sym32_gen->st_value = sym32_fix->st_value;
 383         sym32_gen->st_size = sym32_fix->st_size;
 384         sym32_gen->st_info = sym32_fix->st_info;
 385         sym32_gen->st_other = sym32_fix->st_other;
 386         sym32_gen->st_shndx = sym32_fix->st_shndx;
 387
 388         return 0;
 389 }
 390
 391
 392 #ifdef CONFIG_PPC64
 393
 394 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 395                                   unsigned long *size)
 396 {
 397         Elf64_Shdr *sechdrs;
 398         unsigned int i;
 399         char *secnames;
 400
 401         /* Grab section headers and strings so we can tell who is who */
 402         sechdrs = (void *)ehdr + ehdr->e_shoff;
 403         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 404
 405         /* Find the section they want */
 406         for (i = 1; i < ehdr->e_shnum; i++) {
 407                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 408                         if (size)
 409                                 *size = sechdrs[i].sh_size;
 410                         return (void *)ehdr + sechdrs[i].sh_offset;
 411                 }
 412         }
 413         if (size)
 414                 *size = 0;
 415         return NULL;
 416 }
 417
 418 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 419                                         const char *symname)
 420 {
 421         unsigned int i;
 422         char name[MAX_SYMNAME], *c;
 423
 424         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 425                 if (lib->dynsym[i].st_name == 0)
 426                         continue;
 427                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 428                         MAX_SYMNAME);
 429                 c = strchr(name, '@');
 430                 if (c)
 431                         *c = 0;
 432                 if (strcmp(symname, name) == 0)
 433                         return &lib->dynsym[i];
 434         }
 435         return NULL;
 436 }
 437
 438 /* Note that we assume the section is .text and the symbol is relative to
 439  * the library base
 440  */
 441 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 442                                             const char *symname)
 443 {
 444         Elf64_Sym *sym = find_symbol64(lib, symname);
 445
 446         if (sym == NULL) {
 447                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 448                        symname);
 449                 return 0;
 450         }
 451 #ifdef VDS64_HAS_DESCRIPTORS
 452         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 453                 VDSO64_LBASE;
 454 #else
 455         return sym->st_value - VDSO64_LBASE;
 456 #endif
 457 }
 458
 459 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 460                                 struct lib64_elfinfo *v64,
 461                                 const char *orig, const char *fix)
 462 {
 463         Elf64_Sym *sym64_gen, *sym64_fix;
 464
 465         sym64_gen = find_symbol64(v64, orig);
 466         if (sym64_gen == NULL) {
 467                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 468                 return -1;
 469         }
 470         if (fix == NULL) {
 471                 sym64_gen->st_name = 0;
 472                 return 0;
 473         }
 474         sym64_fix = find_symbol64(v64, fix);
 475         if (sym64_fix == NULL) {
 476                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 477                 return -1;
 478         }
 479         sym64_gen->st_value = sym64_fix->st_value;
 480         sym64_gen->st_size = sym64_fix->st_size;
 481         sym64_gen->st_info = sym64_fix->st_info;
 482         sym64_gen->st_other = sym64_fix->st_other;
 483         sym64_gen->st_shndx = sym64_fix->st_shndx;
 484
 485         return 0;
 486 }
 487
 488 #endif /* CONFIG_PPC64 */
 489
 490
 491 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 492                                         struct lib64_elfinfo *v64)
 493 {
 494         void *sect;
 495
 496         /*
 497          * Locate symbol tables & text section
 498          */
 499
 500         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 501         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 502         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 503                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 504                 return -1;
 505         }
 506         sect = find_section32(v32->hdr, ".text", NULL);
 507         if (sect == NULL) {
 508                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 509                 return -1;
 510         }
 511         v32->text = sect - vdso32_kbase;
 512
 513 #ifdef CONFIG_PPC64
 514         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 515         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 516         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 517                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 518                 return -1;
 519         }
 520         sect = find_section64(v64->hdr, ".text", NULL);
 521         if (sect == NULL) {
 522                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 523                 return -1;
 524         }
 525         v64->text = sect - vdso64_kbase;
 526 #endif /* CONFIG_PPC64 */
 527
 528         return 0;
 529 }
 530
 531 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 532                                           struct lib64_elfinfo *v64)
 533 {
 534         /*
 535          * Find signal trampolines
 536          */
 537
 538 #ifdef CONFIG_PPC64
 539         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 540 #endif
 541         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 542         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 543 }
 544
 545 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 546                                        struct lib64_elfinfo *v64)
 547 {
 548         Elf32_Sym *sym32;
 549 #ifdef CONFIG_PPC64
 550         Elf64_Sym *sym64;
 551
 552         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 553         if (sym64 == NULL) {
 554                 printk(KERN_ERR "vDSO64: Can't find symbol "
 555                        "__kernel_datapage_offset !\n");
 556                 return -1;
 557         }
 558         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 559                 (vdso64_pages << PAGE_SHIFT) -
 560                 (sym64->st_value - VDSO64_LBASE);
 561 #endif /* CONFIG_PPC64 */
 562
 563         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 564         if (sym32 == NULL) {
 565                 printk(KERN_ERR "vDSO32: Can't find symbol "
 566                        "__kernel_datapage_offset !\n");
 567                 return -1;
 568         }
 569         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 570                 (vdso32_pages << PAGE_SHIFT) -
 571                 (sym32->st_value - VDSO32_LBASE);
 572
 573         return 0;
 574 }
 575
 576 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 577                                        struct lib64_elfinfo *v64)
 578 {
 579         int i;
 580
 581         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 582                 struct vdso_patch_def *patch = &vdso_patches[i];
 583                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 584                         == patch->ftr_value;
 585                 if (!match)
 586                         continue;
 587
 588                 DBG("replacing %s with %s...\n", patch->gen_name,
 589                     patch->fix_name ? "NONE" : patch->fix_name);
 590
 591                 /*
 592                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 593                  * patch the "." symbol on 64 bits.
 594                  * It would be easy to do, but doesn't seem to be necessary,
 595                  * patching the OPD symbol is enough.
 596                  */
 597                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 598                                      patch->fix_name);
 599 #ifdef CONFIG_PPC64
 600                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 601                                      patch->fix_name);
 602 #endif /* CONFIG_PPC64 */
 603         }
 604
 605         return 0;
 606 }
 607
 608
 609 static __init int vdso_setup(void)
 610 {
 611         struct lib32_elfinfo    v32;
 612         struct lib64_elfinfo    v64;
 613
 614         v32.hdr = vdso32_kbase;
 615 #ifdef CONFIG_PPC64
 616         v64.hdr = vdso64_kbase;
 617 #endif
 618         if (vdso_do_find_sections(&v32, &v64))
 619                 return -1;
 620
 621         if (vdso_fixup_datapage(&v32, &v64))
 622                 return -1;
 623
 624         if (vdso_fixup_alt_funcs(&v32, &v64))
 625                 return -1;
 626
 627         vdso_setup_trampolines(&v32, &v64);
 628
 629         return 0;
 630 }
 631
 632 /*
 633  * Called from setup_arch to initialize the bitmap of available
 634  * syscalls in the systemcfg page
 635  */
 636 static void __init vdso_setup_syscall_map(void)
 637 {
 638         unsigned int i;
 639         extern unsigned long *sys_call_table;
 640         extern unsigned long sys_ni_syscall;
 641
 642
 643         for (i = 0; i < __NR_syscalls; i++) {
 644 #ifdef CONFIG_PPC64
 645                 if (sys_call_table[i*2] != sys_ni_syscall)
 646                         vdso_data->syscall_map_64[i >> 5] |=
 647                                 0x80000000UL >> (i & 0x1f);
 648                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 649                         vdso_data->syscall_map_32[i >> 5] |=
 650                                 0x80000000UL >> (i & 0x1f);
 651 #else /* CONFIG_PPC64 */
 652                 if (sys_call_table[i] != sys_ni_syscall)
 653                         vdso_data->syscall_map_32[i >> 5] |=
 654                                 0x80000000UL >> (i & 0x1f);
 655 #endif /* CONFIG_PPC64 */
 656         }
 657 }
 658
 659
 660 void __init vdso_init(void)
 661 {
 662         int i;
 663
 664 #ifdef CONFIG_PPC64
 665         /*
 666          * Fill up the "systemcfg" stuff for backward compatiblity
 667          */
 668         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 669         vdso_data->version.major = SYSTEMCFG_MAJOR;
 670         vdso_data->version.minor = SYSTEMCFG_MINOR;
 671         vdso_data->processor = mfspr(SPRN_PVR);
 672         vdso_data->platform = _machine;
 673         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 674         vdso_data->dcache_size = ppc64_caches.dsize;
 675         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 676         vdso_data->icache_size = ppc64_caches.isize;
 677         vdso_data->icache_line_size = ppc64_caches.iline_size;
 678
 679         /*
 680          * Calculate the size of the 64 bits vDSO
 681          */
 682         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 683         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 684 #endif /* CONFIG_PPC64 */
 685
 686
 687         /*
 688          * Calculate the size of the 32 bits vDSO
 689          */
 690         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 691         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 692
 693
 694         /*
 695          * Setup the syscall map in the vDOS
 696          */
 697         vdso_setup_syscall_map();
 698         /*
 699          * Initialize the vDSO images in memory, that is do necessary
 700          * fixups of vDSO symbols, locate trampolines, etc...
 701          */
 702         if (vdso_setup()) {
 703                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 704                 vdso32_pages = 0;
 705 #ifdef CONFIG_PPC64
 706                 vdso64_pages = 0;
 707 #endif
 708                 return;
 709         }
 710
 711         /* Make sure pages are in the correct state */
 712         for (i = 0; i < vdso32_pages; i++) {
 713                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 714                 ClearPageReserved(pg);
 715                 get_page(pg);
 716
 717         }
 718 #ifdef CONFIG_PPC64
 719         for (i = 0; i < vdso64_pages; i++) {
 720                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 721                 ClearPageReserved(pg);
 722                 get_page(pg);
 723         }
 724 #endif /* CONFIG_PPC64 */
 725
 726         get_page(virt_to_page(vdso_data));
 727 }
 728
 729 int in_gate_area_no_task(unsigned long addr)
 730 {
 731         return 0;
 732 }
 733
 734 int in_gate_area(struct task_struct *task, unsigned long addr)
 735 {
 736         return 0;
 737 }
 738
 739 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 740 {
 741         return NULL;
 742 }
 743