arch/powerpc/kernel/vdso.c

   1 /*
   2  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
   3  *                       <benh@kernel.crashing.org>
   4  *
   5  *  This program is free software; you can redistribute it and/or
   6  *  modify it under the terms of the GNU General Public License
   7  *  as published by the Free Software Foundation; either version
   8  *  2 of the License, or (at your option) any later version.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/errno.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/smp.h>
  17 #include <linux/smp_lock.h>
  18 #include <linux/stddef.h>
  19 #include <linux/unistd.h>
  20 #include <linux/slab.h>
  21 #include <linux/user.h>
  22 #include <linux/elf.h>
  23 #include <linux/security.h>
  24 #include <linux/bootmem.h>
  25
  26 #include <asm/pgtable.h>
  27 #include <asm/system.h>
  28 #include <asm/processor.h>
  29 #include <asm/mmu.h>
  30 #include <asm/mmu_context.h>
  31 #include <asm/lmb.h>
  32 #include <asm/machdep.h>
  33 #include <asm/cputable.h>
  34 #include <asm/sections.h>
  35 #include <asm/firmware.h>
  36 #include <asm/vdso.h>
  37 #include <asm/vdso_datapage.h>
  38
  39 #include "setup.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 static unsigned int vdso32_pages;
  55 static struct page **vdso32_pagelist;
  56 unsigned long vdso32_sigtramp;
  57 unsigned long vdso32_rt_sigtramp;
  58
  59 #ifdef CONFIG_PPC64
  60 extern char vdso64_start, vdso64_end;
  61 static void *vdso64_kbase = &vdso64_start;
  62 static unsigned int vdso64_pages;
  63 static struct page **vdso64_pagelist;
  64 unsigned long vdso64_rt_sigtramp;
  65 #endif /* CONFIG_PPC64 */
  66
  67 static int vdso_ready;
  68
  69 /*
  70  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  71  * Once the early boot kernel code no longer needs to muck around
  72  * with it, it will become dynamically allocated
  73  */
  74 static union {
  75         struct vdso_data        data;
  76         u8                      page[PAGE_SIZE];
  77 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  78 struct vdso_data *vdso_data = &vdso_data_store.data;
  79
  80 /* Format of the patch table */
  81 struct vdso_patch_def
  82 {
  83         unsigned long   ftr_mask, ftr_value;
  84         const char      *gen_name;
  85         const char      *fix_name;
  86 };
  87
  88 /* Table of functions to patch based on the CPU type/revision
  89  *
  90  * Currently, we only change sync_dicache to do nothing on processors
  91  * with a coherent icache
  92  */
  93 static struct vdso_patch_def vdso_patches[] = {
  94         {
  95                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  96                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  97         },
  98         {
  99                 CPU_FTR_USE_TB, 0,
 100                 "__kernel_gettimeofday", NULL
 101         },
 102 };
 103
 104 /*
 105  * Some infos carried around for each of them during parsing at
 106  * boot time.
 107  */
 108 struct lib32_elfinfo
 109 {
 110         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 111         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 112         unsigned long   dynsymsize;     /* size of .dynsym section */
 113         char            *dynstr;        /* ptr to .dynstr section */
 114         unsigned long   text;           /* offset of .text section in .so */
 115 };
 116
 117 struct lib64_elfinfo
 118 {
 119         Elf64_Ehdr      *hdr;
 120         Elf64_Sym       *dynsym;
 121         unsigned long   dynsymsize;
 122         char            *dynstr;
 123         unsigned long   text;
 124 };
 125
 126
 127 #ifdef __DEBUG
 128 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 129 {
 130         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 131                page_count(pg),
 132                pg->flags);
 133         if (upg/* && pg != upg*/) {
 134                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 135                                                        << PAGE_SHIFT),
 136                        page_count(upg),
 137                        upg->flags);
 138         }
 139         printk("\n");
 140 }
 141
 142 static void dump_vdso_pages(struct vm_area_struct * vma)
 143 {
 144         int i;
 145
 146         if (!vma || test_thread_flag(TIF_32BIT)) {
 147                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 148                 for (i=0; i<vdso32_pages; i++) {
 149                         struct page *pg = virt_to_page(vdso32_kbase +
 150                                                        i*PAGE_SIZE);
 151                         struct page *upg = (vma && vma->vm_mm) ?
 152                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 153                                 : NULL;
 154                         dump_one_vdso_page(pg, upg);
 155                 }
 156         }
 157         if (!vma || !test_thread_flag(TIF_32BIT)) {
 158                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 159                 for (i=0; i<vdso64_pages; i++) {
 160                         struct page *pg = virt_to_page(vdso64_kbase +
 161                                                        i*PAGE_SIZE);
 162                         struct page *upg = (vma && vma->vm_mm) ?
 163                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 164                                 : NULL;
 165                         dump_one_vdso_page(pg, upg);
 166                 }
 167         }
 168 }
 169 #endif /* DEBUG */
 170
 171 /*
 172  * This is called from binfmt_elf, we create the special vma for the
 173  * vDSO and insert it into the mm struct tree
 174  */
 175 int arch_setup_additional_pages(struct linux_binprm *bprm,
 176                                 int executable_stack)
 177 {
 178         struct mm_struct *mm = current->mm;
 179         struct page **vdso_pagelist;
 180         unsigned long vdso_pages;
 181         unsigned long vdso_base;
 182         int rc;
 183
 184         if (!vdso_ready)
 185                 return 0;
 186
 187 #ifdef CONFIG_PPC64
 188         if (test_thread_flag(TIF_32BIT)) {
 189                 vdso_pagelist = vdso32_pagelist;
 190                 vdso_pages = vdso32_pages;
 191                 vdso_base = VDSO32_MBASE;
 192         } else {
 193                 vdso_pagelist = vdso64_pagelist;
 194                 vdso_pages = vdso64_pages;
 195                 vdso_base = VDSO64_MBASE;
 196         }
 197 #else
 198         vdso_pagelist = vdso32_pagelist;
 199         vdso_pages = vdso32_pages;
 200         vdso_base = VDSO32_MBASE;
 201 #endif
 202
 203         current->mm->context.vdso_base = 0;
 204
 205         /* vDSO has a problem and was disabled, just don't "enable" it for the
 206          * process
 207          */
 208         if (vdso_pages == 0)
 209                 return 0;
 210         /* Add a page to the vdso size for the data page */
 211         vdso_pages ++;
 212
 213         /*
 214          * pick a base address for the vDSO in process space. We try to put it
 215          * at vdso_base which is the "natural" base for it, but we might fail
 216          * and end up putting it elsewhere.
 217          */
 218         down_write(&mm->mmap_sem);
 219         vdso_base = get_unmapped_area(NULL, vdso_base,
 220                                       vdso_pages << PAGE_SHIFT, 0, 0);
 221         if (IS_ERR_VALUE(vdso_base)) {
 222                 rc = vdso_base;
 223                 goto fail_mmapsem;
 224         }
 225
 226         /*
 227          * our vma flags don't have VM_WRITE so by default, the process isn't
 228          * allowed to write those pages.
 229          * gdb can break that with ptrace interface, and thus trigger COW on
 230          * those pages but it's then your responsibility to never do that on
 231          * the "data" page of the vDSO or you'll stop getting kernel updates
 232          * and your nice userland gettimeofday will be totally dead.
 233          * It's fine to use that for setting breakpoints in the vDSO code
 234          * pages though
 235          *
 236          * Make sure the vDSO gets into every core dump.
 237          * Dumping its contents makes post-mortem fully interpretable later
 238          * without matching up the same kernel and hardware config to see
 239          * what PC values meant.
 240          */
 241         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 242                                      VM_READ|VM_EXEC|
 243                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
 244                                      VM_ALWAYSDUMP,
 245                                      vdso_pagelist);
 246         if (rc)
 247                 goto fail_mmapsem;
 248
 249         /* Put vDSO base into mm struct */
 250         current->mm->context.vdso_base = vdso_base;
 251
 252         up_write(&mm->mmap_sem);
 253         return 0;
 254
 255  fail_mmapsem:
 256         up_write(&mm->mmap_sem);
 257         return rc;
 258 }
 259
 260 const char *arch_vma_name(struct vm_area_struct *vma)
 261 {
 262         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 263                 return "[vdso]";
 264         return NULL;
 265 }
 266
 267
 268
 269 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 270                                   unsigned long *size)
 271 {
 272         Elf32_Shdr *sechdrs;
 273         unsigned int i;
 274         char *secnames;
 275
 276         /* Grab section headers and strings so we can tell who is who */
 277         sechdrs = (void *)ehdr + ehdr->e_shoff;
 278         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 279
 280         /* Find the section they want */
 281         for (i = 1; i < ehdr->e_shnum; i++) {
 282                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 283                         if (size)
 284                                 *size = sechdrs[i].sh_size;
 285                         return (void *)ehdr + sechdrs[i].sh_offset;
 286                 }
 287         }
 288         *size = 0;
 289         return NULL;
 290 }
 291
 292 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 293                                         const char *symname)
 294 {
 295         unsigned int i;
 296         char name[MAX_SYMNAME], *c;
 297
 298         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 299                 if (lib->dynsym[i].st_name == 0)
 300                         continue;
 301                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 302                         MAX_SYMNAME);
 303                 c = strchr(name, '@');
 304                 if (c)
 305                         *c = 0;
 306                 if (strcmp(symname, name) == 0)
 307                         return &lib->dynsym[i];
 308         }
 309         return NULL;
 310 }
 311
 312 /* Note that we assume the section is .text and the symbol is relative to
 313  * the library base
 314  */
 315 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 316                                             const char *symname)
 317 {
 318         Elf32_Sym *sym = find_symbol32(lib, symname);
 319
 320         if (sym == NULL) {
 321                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 322                        symname);
 323                 return 0;
 324         }
 325         return sym->st_value - VDSO32_LBASE;
 326 }
 327
 328 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 329                                 struct lib64_elfinfo *v64,
 330                                 const char *orig, const char *fix)
 331 {
 332         Elf32_Sym *sym32_gen, *sym32_fix;
 333
 334         sym32_gen = find_symbol32(v32, orig);
 335         if (sym32_gen == NULL) {
 336                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 337                 return -1;
 338         }
 339         if (fix == NULL) {
 340                 sym32_gen->st_name = 0;
 341                 return 0;
 342         }
 343         sym32_fix = find_symbol32(v32, fix);
 344         if (sym32_fix == NULL) {
 345                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 346                 return -1;
 347         }
 348         sym32_gen->st_value = sym32_fix->st_value;
 349         sym32_gen->st_size = sym32_fix->st_size;
 350         sym32_gen->st_info = sym32_fix->st_info;
 351         sym32_gen->st_other = sym32_fix->st_other;
 352         sym32_gen->st_shndx = sym32_fix->st_shndx;
 353
 354         return 0;
 355 }
 356
 357
 358 #ifdef CONFIG_PPC64
 359
 360 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 361                                   unsigned long *size)
 362 {
 363         Elf64_Shdr *sechdrs;
 364         unsigned int i;
 365         char *secnames;
 366
 367         /* Grab section headers and strings so we can tell who is who */
 368         sechdrs = (void *)ehdr + ehdr->e_shoff;
 369         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 370
 371         /* Find the section they want */
 372         for (i = 1; i < ehdr->e_shnum; i++) {
 373                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 374                         if (size)
 375                                 *size = sechdrs[i].sh_size;
 376                         return (void *)ehdr + sechdrs[i].sh_offset;
 377                 }
 378         }
 379         if (size)
 380                 *size = 0;
 381         return NULL;
 382 }
 383
 384 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 385                                         const char *symname)
 386 {
 387         unsigned int i;
 388         char name[MAX_SYMNAME], *c;
 389
 390         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 391                 if (lib->dynsym[i].st_name == 0)
 392                         continue;
 393                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 394                         MAX_SYMNAME);
 395                 c = strchr(name, '@');
 396                 if (c)
 397                         *c = 0;
 398                 if (strcmp(symname, name) == 0)
 399                         return &lib->dynsym[i];
 400         }
 401         return NULL;
 402 }
 403
 404 /* Note that we assume the section is .text and the symbol is relative to
 405  * the library base
 406  */
 407 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 408                                             const char *symname)
 409 {
 410         Elf64_Sym *sym = find_symbol64(lib, symname);
 411
 412         if (sym == NULL) {
 413                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 414                        symname);
 415                 return 0;
 416         }
 417 #ifdef VDS64_HAS_DESCRIPTORS
 418         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 419                 VDSO64_LBASE;
 420 #else
 421         return sym->st_value - VDSO64_LBASE;
 422 #endif
 423 }
 424
 425 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 426                                 struct lib64_elfinfo *v64,
 427                                 const char *orig, const char *fix)
 428 {
 429         Elf64_Sym *sym64_gen, *sym64_fix;
 430
 431         sym64_gen = find_symbol64(v64, orig);
 432         if (sym64_gen == NULL) {
 433                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 434                 return -1;
 435         }
 436         if (fix == NULL) {
 437                 sym64_gen->st_name = 0;
 438                 return 0;
 439         }
 440         sym64_fix = find_symbol64(v64, fix);
 441         if (sym64_fix == NULL) {
 442                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 443                 return -1;
 444         }
 445         sym64_gen->st_value = sym64_fix->st_value;
 446         sym64_gen->st_size = sym64_fix->st_size;
 447         sym64_gen->st_info = sym64_fix->st_info;
 448         sym64_gen->st_other = sym64_fix->st_other;
 449         sym64_gen->st_shndx = sym64_fix->st_shndx;
 450
 451         return 0;
 452 }
 453
 454 #endif /* CONFIG_PPC64 */
 455
 456
 457 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 458                                         struct lib64_elfinfo *v64)
 459 {
 460         void *sect;
 461
 462         /*
 463          * Locate symbol tables & text section
 464          */
 465
 466         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 467         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 468         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 469                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 470                 return -1;
 471         }
 472         sect = find_section32(v32->hdr, ".text", NULL);
 473         if (sect == NULL) {
 474                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 475                 return -1;
 476         }
 477         v32->text = sect - vdso32_kbase;
 478
 479 #ifdef CONFIG_PPC64
 480         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 481         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 482         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 483                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 484                 return -1;
 485         }
 486         sect = find_section64(v64->hdr, ".text", NULL);
 487         if (sect == NULL) {
 488                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 489                 return -1;
 490         }
 491         v64->text = sect - vdso64_kbase;
 492 #endif /* CONFIG_PPC64 */
 493
 494         return 0;
 495 }
 496
 497 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 498                                           struct lib64_elfinfo *v64)
 499 {
 500         /*
 501          * Find signal trampolines
 502          */
 503
 504 #ifdef CONFIG_PPC64
 505         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 506 #endif
 507         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 508         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 509 }
 510
 511 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 512                                        struct lib64_elfinfo *v64)
 513 {
 514         Elf32_Sym *sym32;
 515 #ifdef CONFIG_PPC64
 516         Elf64_Sym *sym64;
 517
 518         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 519         if (sym64 == NULL) {
 520                 printk(KERN_ERR "vDSO64: Can't find symbol "
 521                        "__kernel_datapage_offset !\n");
 522                 return -1;
 523         }
 524         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 525                 (vdso64_pages << PAGE_SHIFT) -
 526                 (sym64->st_value - VDSO64_LBASE);
 527 #endif /* CONFIG_PPC64 */
 528
 529         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 530         if (sym32 == NULL) {
 531                 printk(KERN_ERR "vDSO32: Can't find symbol "
 532                        "__kernel_datapage_offset !\n");
 533                 return -1;
 534         }
 535         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 536                 (vdso32_pages << PAGE_SHIFT) -
 537                 (sym32->st_value - VDSO32_LBASE);
 538
 539         return 0;
 540 }
 541
 542
 543 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 544                                       struct lib64_elfinfo *v64)
 545 {
 546         void *start32;
 547         unsigned long size32;
 548
 549 #ifdef CONFIG_PPC64
 550         void *start64;
 551         unsigned long size64;
 552
 553         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 554         if (start64)
 555                 do_feature_fixups(cur_cpu_spec->cpu_features,
 556                                   start64, start64 + size64);
 557
 558         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 559         if (start64)
 560                 do_feature_fixups(powerpc_firmware_features,
 561                                   start64, start64 + size64);
 562 #endif /* CONFIG_PPC64 */
 563
 564         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 565         if (start32)
 566                 do_feature_fixups(cur_cpu_spec->cpu_features,
 567                                   start32, start32 + size32);
 568
 569 #ifdef CONFIG_PPC64
 570         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 571         if (start32)
 572                 do_feature_fixups(powerpc_firmware_features,
 573                                   start32, start32 + size32);
 574 #endif /* CONFIG_PPC64 */
 575
 576         return 0;
 577 }
 578
 579 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 580                                        struct lib64_elfinfo *v64)
 581 {
 582         int i;
 583
 584         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 585                 struct vdso_patch_def *patch = &vdso_patches[i];
 586                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 587                         == patch->ftr_value;
 588                 if (!match)
 589                         continue;
 590
 591                 DBG("replacing %s with %s...\n", patch->gen_name,
 592                     patch->fix_name ? "NONE" : patch->fix_name);
 593
 594                 /*
 595                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 596                  * patch the "." symbol on 64 bits.
 597                  * It would be easy to do, but doesn't seem to be necessary,
 598                  * patching the OPD symbol is enough.
 599                  */
 600                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 601                                      patch->fix_name);
 602 #ifdef CONFIG_PPC64
 603                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 604                                      patch->fix_name);
 605 #endif /* CONFIG_PPC64 */
 606         }
 607
 608         return 0;
 609 }
 610
 611
 612 static __init int vdso_setup(void)
 613 {
 614         struct lib32_elfinfo    v32;
 615         struct lib64_elfinfo    v64;
 616
 617         v32.hdr = vdso32_kbase;
 618 #ifdef CONFIG_PPC64
 619         v64.hdr = vdso64_kbase;
 620 #endif
 621         if (vdso_do_find_sections(&v32, &v64))
 622                 return -1;
 623
 624         if (vdso_fixup_datapage(&v32, &v64))
 625                 return -1;
 626
 627         if (vdso_fixup_features(&v32, &v64))
 628                 return -1;
 629
 630         if (vdso_fixup_alt_funcs(&v32, &v64))
 631                 return -1;
 632
 633         vdso_setup_trampolines(&v32, &v64);
 634
 635         return 0;
 636 }
 637
 638 /*
 639  * Called from setup_arch to initialize the bitmap of available
 640  * syscalls in the systemcfg page
 641  */
 642 static void __init vdso_setup_syscall_map(void)
 643 {
 644         unsigned int i;
 645         extern unsigned long *sys_call_table;
 646         extern unsigned long sys_ni_syscall;
 647
 648
 649         for (i = 0; i < __NR_syscalls; i++) {
 650 #ifdef CONFIG_PPC64
 651                 if (sys_call_table[i*2] != sys_ni_syscall)
 652                         vdso_data->syscall_map_64[i >> 5] |=
 653                                 0x80000000UL >> (i & 0x1f);
 654                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 655                         vdso_data->syscall_map_32[i >> 5] |=
 656                                 0x80000000UL >> (i & 0x1f);
 657 #else /* CONFIG_PPC64 */
 658                 if (sys_call_table[i] != sys_ni_syscall)
 659                         vdso_data->syscall_map_32[i >> 5] |=
 660                                 0x80000000UL >> (i & 0x1f);
 661 #endif /* CONFIG_PPC64 */
 662         }
 663 }
 664
 665
 666 static int __init vdso_init(void)
 667 {
 668         int i;
 669
 670 #ifdef CONFIG_PPC64
 671         /*
 672          * Fill up the "systemcfg" stuff for backward compatiblity
 673          */
 674         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 675         vdso_data->version.major = SYSTEMCFG_MAJOR;
 676         vdso_data->version.minor = SYSTEMCFG_MINOR;
 677         vdso_data->processor = mfspr(SPRN_PVR);
 678         /*
 679          * Fake the old platform number for pSeries and iSeries and add
 680          * in LPAR bit if necessary
 681          */
 682         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 683         if (firmware_has_feature(FW_FEATURE_LPAR))
 684                 vdso_data->platform |= 1;
 685         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 686         vdso_data->dcache_size = ppc64_caches.dsize;
 687         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 688         vdso_data->icache_size = ppc64_caches.isize;
 689         vdso_data->icache_line_size = ppc64_caches.iline_size;
 690
 691         /*
 692          * Calculate the size of the 64 bits vDSO
 693          */
 694         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 695         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 696 #endif /* CONFIG_PPC64 */
 697
 698
 699         /*
 700          * Calculate the size of the 32 bits vDSO
 701          */
 702         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 703         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 704
 705
 706         /*
 707          * Setup the syscall map in the vDOS
 708          */
 709         vdso_setup_syscall_map();
 710
 711         /*
 712          * Initialize the vDSO images in memory, that is do necessary
 713          * fixups of vDSO symbols, locate trampolines, etc...
 714          */
 715         if (vdso_setup()) {
 716                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 717                 vdso32_pages = 0;
 718 #ifdef CONFIG_PPC64
 719                 vdso64_pages = 0;
 720 #endif
 721                 return 0;
 722         }
 723
 724         /* Make sure pages are in the correct state */
 725         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 726                                   GFP_KERNEL);
 727         BUG_ON(vdso32_pagelist == NULL);
 728         for (i = 0; i < vdso32_pages; i++) {
 729                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 730                 ClearPageReserved(pg);
 731                 get_page(pg);
 732                 vdso32_pagelist[i] = pg;
 733         }
 734         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 735         vdso32_pagelist[i] = NULL;
 736
 737 #ifdef CONFIG_PPC64
 738         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 739                                   GFP_KERNEL);
 740         BUG_ON(vdso64_pagelist == NULL);
 741         for (i = 0; i < vdso64_pages; i++) {
 742                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 743                 ClearPageReserved(pg);
 744                 get_page(pg);
 745                 vdso64_pagelist[i] = pg;
 746         }
 747         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 748         vdso64_pagelist[i] = NULL;
 749 #endif /* CONFIG_PPC64 */
 750
 751         get_page(virt_to_page(vdso_data));
 752
 753         smp_wmb();
 754         vdso_ready = 1;
 755
 756         return 0;
 757 }
 758 arch_initcall(vdso_init);
 759
 760 int in_gate_area_no_task(unsigned long addr)
 761 {
 762         return 0;
 763 }
 764
 765 int in_gate_area(struct task_struct *task, unsigned long addr)
 766 {
 767         return 0;
 768 }
 769
 770 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 771 {
 772         return NULL;
 773 }
 774