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/stddef.h>
  18 #include <linux/unistd.h>
  19 #include <linux/slab.h>
  20 #include <linux/user.h>
  21 #include <linux/elf.h>
  22 #include <linux/security.h>
  23 #include <linux/bootmem.h>
  24
  25 #include <asm/pgtable.h>
  26 #include <asm/system.h>
  27 #include <asm/processor.h>
  28 #include <asm/mmu.h>
  29 #include <asm/mmu_context.h>
  30 #include <asm/lmb.h>
  31 #include <asm/machdep.h>
  32 #include <asm/cputable.h>
  33 #include <asm/sections.h>
  34 #include <asm/firmware.h>
  35 #include <asm/vdso.h>
  36 #include <asm/vdso_datapage.h>
  37
  38 #include "setup.h"
  39
  40 #undef DEBUG
  41
  42 #ifdef DEBUG
  43 #define DBG(fmt...) printk(fmt)
  44 #else
  45 #define DBG(fmt...)
  46 #endif
  47
  48 /* Max supported size for symbol names */
  49 #define MAX_SYMNAME     64
  50
  51 extern char vdso32_start, vdso32_end;
  52 static void *vdso32_kbase = &vdso32_start;
  53 static unsigned int vdso32_pages;
  54 static struct page **vdso32_pagelist;
  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 static unsigned int vdso64_pages;
  62 static struct page **vdso64_pagelist;
  63 unsigned long vdso64_rt_sigtramp;
  64 #endif /* CONFIG_PPC64 */
  65
  66 static int vdso_ready;
  67
  68 /*
  69  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  70  * Once the early boot kernel code no longer needs to muck around
  71  * with it, it will become dynamically allocated
  72  */
  73 static union {
  74         struct vdso_data        data;
  75         u8                      page[PAGE_SIZE];
  76 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  77 struct vdso_data *vdso_data = &vdso_data_store.data;
  78
  79 /* Format of the patch table */
  80 struct vdso_patch_def
  81 {
  82         unsigned long   ftr_mask, ftr_value;
  83         const char      *gen_name;
  84         const char      *fix_name;
  85 };
  86
  87 /* Table of functions to patch based on the CPU type/revision
  88  *
  89  * Currently, we only change sync_dicache to do nothing on processors
  90  * with a coherent icache
  91  */
  92 static struct vdso_patch_def vdso_patches[] = {
  93         {
  94                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  95                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  96         },
  97         {
  98                 CPU_FTR_USE_TB, 0,
  99                 "__kernel_gettimeofday", NULL
 100         },
 101 };
 102
 103 /*
 104  * Some infos carried around for each of them during parsing at
 105  * boot time.
 106  */
 107 struct lib32_elfinfo
 108 {
 109         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 110         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 111         unsigned long   dynsymsize;     /* size of .dynsym section */
 112         char            *dynstr;        /* ptr to .dynstr section */
 113         unsigned long   text;           /* offset of .text section in .so */
 114 };
 115
 116 struct lib64_elfinfo
 117 {
 118         Elf64_Ehdr      *hdr;
 119         Elf64_Sym       *dynsym;
 120         unsigned long   dynsymsize;
 121         char            *dynstr;
 122         unsigned long   text;
 123 };
 124
 125
 126 #ifdef __DEBUG
 127 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 128 {
 129         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 130                page_count(pg),
 131                pg->flags);
 132         if (upg/* && pg != upg*/) {
 133                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 134                                                        << PAGE_SHIFT),
 135                        page_count(upg),
 136                        upg->flags);
 137         }
 138         printk("\n");
 139 }
 140
 141 static void dump_vdso_pages(struct vm_area_struct * vma)
 142 {
 143         int i;
 144
 145         if (!vma || test_thread_flag(TIF_32BIT)) {
 146                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 147                 for (i=0; i<vdso32_pages; i++) {
 148                         struct page *pg = virt_to_page(vdso32_kbase +
 149                                                        i*PAGE_SIZE);
 150                         struct page *upg = (vma && vma->vm_mm) ?
 151                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 152                                 : NULL;
 153                         dump_one_vdso_page(pg, upg);
 154                 }
 155         }
 156         if (!vma || !test_thread_flag(TIF_32BIT)) {
 157                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 158                 for (i=0; i<vdso64_pages; i++) {
 159                         struct page *pg = virt_to_page(vdso64_kbase +
 160                                                        i*PAGE_SIZE);
 161                         struct page *upg = (vma && vma->vm_mm) ?
 162                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 163                                 : NULL;
 164                         dump_one_vdso_page(pg, upg);
 165                 }
 166         }
 167 }
 168 #endif /* DEBUG */
 169
 170 /*
 171  * This is called from binfmt_elf, we create the special vma for the
 172  * vDSO and insert it into the mm struct tree
 173  */
 174 int arch_setup_additional_pages(struct linux_binprm *bprm,
 175                                 int executable_stack)
 176 {
 177         struct mm_struct *mm = current->mm;
 178         struct page **vdso_pagelist;
 179         unsigned long vdso_pages;
 180         unsigned long vdso_base;
 181         int rc;
 182
 183         if (!vdso_ready)
 184                 return 0;
 185
 186 #ifdef CONFIG_PPC64
 187         if (test_thread_flag(TIF_32BIT)) {
 188                 vdso_pagelist = vdso32_pagelist;
 189                 vdso_pages = vdso32_pages;
 190                 vdso_base = VDSO32_MBASE;
 191         } else {
 192                 vdso_pagelist = vdso64_pagelist;
 193                 vdso_pages = vdso64_pages;
 194                 vdso_base = VDSO64_MBASE;
 195         }
 196 #else
 197         vdso_pagelist = vdso32_pagelist;
 198         vdso_pages = vdso32_pages;
 199         vdso_base = VDSO32_MBASE;
 200 #endif
 201
 202         current->mm->context.vdso_base = 0;
 203
 204         /* vDSO has a problem and was disabled, just don't "enable" it for the
 205          * process
 206          */
 207         if (vdso_pages == 0)
 208                 return 0;
 209         /* Add a page to the vdso size for the data page */
 210         vdso_pages ++;
 211
 212         /*
 213          * pick a base address for the vDSO in process space. We try to put it
 214          * at vdso_base which is the "natural" base for it, but we might fail
 215          * and end up putting it elsewhere.
 216          */
 217         down_write(&mm->mmap_sem);
 218         vdso_base = get_unmapped_area(NULL, vdso_base,
 219                                       vdso_pages << PAGE_SHIFT, 0, 0);
 220         if (IS_ERR_VALUE(vdso_base)) {
 221                 rc = vdso_base;
 222                 goto fail_mmapsem;
 223         }
 224
 225         /*
 226          * our vma flags don't have VM_WRITE so by default, the process isn't
 227          * allowed to write those pages.
 228          * gdb can break that with ptrace interface, and thus trigger COW on
 229          * those pages but it's then your responsibility to never do that on
 230          * the "data" page of the vDSO or you'll stop getting kernel updates
 231          * and your nice userland gettimeofday will be totally dead.
 232          * It's fine to use that for setting breakpoints in the vDSO code
 233          * pages though
 234          *
 235          * Make sure the vDSO gets into every core dump.
 236          * Dumping its contents makes post-mortem fully interpretable later
 237          * without matching up the same kernel and hardware config to see
 238          * what PC values meant.
 239          */
 240         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 241                                      VM_READ|VM_EXEC|
 242                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
 243                                      VM_ALWAYSDUMP,
 244                                      vdso_pagelist);
 245         if (rc)
 246                 goto fail_mmapsem;
 247
 248         /* Put vDSO base into mm struct */
 249         current->mm->context.vdso_base = vdso_base;
 250
 251         up_write(&mm->mmap_sem);
 252         return 0;
 253
 254  fail_mmapsem:
 255         up_write(&mm->mmap_sem);
 256         return rc;
 257 }
 258
 259 const char *arch_vma_name(struct vm_area_struct *vma)
 260 {
 261         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 262                 return "[vdso]";
 263         return NULL;
 264 }
 265
 266
 267
 268 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 269                                   unsigned long *size)
 270 {
 271         Elf32_Shdr *sechdrs;
 272         unsigned int i;
 273         char *secnames;
 274
 275         /* Grab section headers and strings so we can tell who is who */
 276         sechdrs = (void *)ehdr + ehdr->e_shoff;
 277         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 278
 279         /* Find the section they want */
 280         for (i = 1; i < ehdr->e_shnum; i++) {
 281                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 282                         if (size)
 283                                 *size = sechdrs[i].sh_size;
 284                         return (void *)ehdr + sechdrs[i].sh_offset;
 285                 }
 286         }
 287         *size = 0;
 288         return NULL;
 289 }
 290
 291 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 292                                         const char *symname)
 293 {
 294         unsigned int i;
 295         char name[MAX_SYMNAME], *c;
 296
 297         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 298                 if (lib->dynsym[i].st_name == 0)
 299                         continue;
 300                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 301                         MAX_SYMNAME);
 302                 c = strchr(name, '@');
 303                 if (c)
 304                         *c = 0;
 305                 if (strcmp(symname, name) == 0)
 306                         return &lib->dynsym[i];
 307         }
 308         return NULL;
 309 }
 310
 311 /* Note that we assume the section is .text and the symbol is relative to
 312  * the library base
 313  */
 314 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 315                                             const char *symname)
 316 {
 317         Elf32_Sym *sym = find_symbol32(lib, symname);
 318
 319         if (sym == NULL) {
 320                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 321                        symname);
 322                 return 0;
 323         }
 324         return sym->st_value - VDSO32_LBASE;
 325 }
 326
 327 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 328                                 struct lib64_elfinfo *v64,
 329                                 const char *orig, const char *fix)
 330 {
 331         Elf32_Sym *sym32_gen, *sym32_fix;
 332
 333         sym32_gen = find_symbol32(v32, orig);
 334         if (sym32_gen == NULL) {
 335                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 336                 return -1;
 337         }
 338         if (fix == NULL) {
 339                 sym32_gen->st_name = 0;
 340                 return 0;
 341         }
 342         sym32_fix = find_symbol32(v32, fix);
 343         if (sym32_fix == NULL) {
 344                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 345                 return -1;
 346         }
 347         sym32_gen->st_value = sym32_fix->st_value;
 348         sym32_gen->st_size = sym32_fix->st_size;
 349         sym32_gen->st_info = sym32_fix->st_info;
 350         sym32_gen->st_other = sym32_fix->st_other;
 351         sym32_gen->st_shndx = sym32_fix->st_shndx;
 352
 353         return 0;
 354 }
 355
 356
 357 #ifdef CONFIG_PPC64
 358
 359 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 360                                   unsigned long *size)
 361 {
 362         Elf64_Shdr *sechdrs;
 363         unsigned int i;
 364         char *secnames;
 365
 366         /* Grab section headers and strings so we can tell who is who */
 367         sechdrs = (void *)ehdr + ehdr->e_shoff;
 368         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 369
 370         /* Find the section they want */
 371         for (i = 1; i < ehdr->e_shnum; i++) {
 372                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 373                         if (size)
 374                                 *size = sechdrs[i].sh_size;
 375                         return (void *)ehdr + sechdrs[i].sh_offset;
 376                 }
 377         }
 378         if (size)
 379                 *size = 0;
 380         return NULL;
 381 }
 382
 383 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 384                                         const char *symname)
 385 {
 386         unsigned int i;
 387         char name[MAX_SYMNAME], *c;
 388
 389         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 390                 if (lib->dynsym[i].st_name == 0)
 391                         continue;
 392                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 393                         MAX_SYMNAME);
 394                 c = strchr(name, '@');
 395                 if (c)
 396                         *c = 0;
 397                 if (strcmp(symname, name) == 0)
 398                         return &lib->dynsym[i];
 399         }
 400         return NULL;
 401 }
 402
 403 /* Note that we assume the section is .text and the symbol is relative to
 404  * the library base
 405  */
 406 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 407                                             const char *symname)
 408 {
 409         Elf64_Sym *sym = find_symbol64(lib, symname);
 410
 411         if (sym == NULL) {
 412                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 413                        symname);
 414                 return 0;
 415         }
 416 #ifdef VDS64_HAS_DESCRIPTORS
 417         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 418                 VDSO64_LBASE;
 419 #else
 420         return sym->st_value - VDSO64_LBASE;
 421 #endif
 422 }
 423
 424 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 425                                 struct lib64_elfinfo *v64,
 426                                 const char *orig, const char *fix)
 427 {
 428         Elf64_Sym *sym64_gen, *sym64_fix;
 429
 430         sym64_gen = find_symbol64(v64, orig);
 431         if (sym64_gen == NULL) {
 432                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 433                 return -1;
 434         }
 435         if (fix == NULL) {
 436                 sym64_gen->st_name = 0;
 437                 return 0;
 438         }
 439         sym64_fix = find_symbol64(v64, fix);
 440         if (sym64_fix == NULL) {
 441                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 442                 return -1;
 443         }
 444         sym64_gen->st_value = sym64_fix->st_value;
 445         sym64_gen->st_size = sym64_fix->st_size;
 446         sym64_gen->st_info = sym64_fix->st_info;
 447         sym64_gen->st_other = sym64_fix->st_other;
 448         sym64_gen->st_shndx = sym64_fix->st_shndx;
 449
 450         return 0;
 451 }
 452
 453 #endif /* CONFIG_PPC64 */
 454
 455
 456 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 457                                         struct lib64_elfinfo *v64)
 458 {
 459         void *sect;
 460
 461         /*
 462          * Locate symbol tables & text section
 463          */
 464
 465         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 466         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 467         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 468                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 469                 return -1;
 470         }
 471         sect = find_section32(v32->hdr, ".text", NULL);
 472         if (sect == NULL) {
 473                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 474                 return -1;
 475         }
 476         v32->text = sect - vdso32_kbase;
 477
 478 #ifdef CONFIG_PPC64
 479         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 480         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 481         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 482                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 483                 return -1;
 484         }
 485         sect = find_section64(v64->hdr, ".text", NULL);
 486         if (sect == NULL) {
 487                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 488                 return -1;
 489         }
 490         v64->text = sect - vdso64_kbase;
 491 #endif /* CONFIG_PPC64 */
 492
 493         return 0;
 494 }
 495
 496 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 497                                           struct lib64_elfinfo *v64)
 498 {
 499         /*
 500          * Find signal trampolines
 501          */
 502
 503 #ifdef CONFIG_PPC64
 504         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 505 #endif
 506         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 507         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 508 }
 509
 510 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 511                                        struct lib64_elfinfo *v64)
 512 {
 513         Elf32_Sym *sym32;
 514 #ifdef CONFIG_PPC64
 515         Elf64_Sym *sym64;
 516
 517         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 518         if (sym64 == NULL) {
 519                 printk(KERN_ERR "vDSO64: Can't find symbol "
 520                        "__kernel_datapage_offset !\n");
 521                 return -1;
 522         }
 523         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 524                 (vdso64_pages << PAGE_SHIFT) -
 525                 (sym64->st_value - VDSO64_LBASE);
 526 #endif /* CONFIG_PPC64 */
 527
 528         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 529         if (sym32 == NULL) {
 530                 printk(KERN_ERR "vDSO32: Can't find symbol "
 531                        "__kernel_datapage_offset !\n");
 532                 return -1;
 533         }
 534         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 535                 (vdso32_pages << PAGE_SHIFT) -
 536                 (sym32->st_value - VDSO32_LBASE);
 537
 538         return 0;
 539 }
 540
 541
 542 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 543                                       struct lib64_elfinfo *v64)
 544 {
 545         void *start32;
 546         unsigned long size32;
 547
 548 #ifdef CONFIG_PPC64
 549         void *start64;
 550         unsigned long size64;
 551
 552         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 553         if (start64)
 554                 do_feature_fixups(cur_cpu_spec->cpu_features,
 555                                   start64, start64 + size64);
 556
 557         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 558         if (start64)
 559                 do_feature_fixups(powerpc_firmware_features,
 560                                   start64, start64 + size64);
 561 #endif /* CONFIG_PPC64 */
 562
 563         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 564         if (start32)
 565                 do_feature_fixups(cur_cpu_spec->cpu_features,
 566                                   start32, start32 + size32);
 567
 568 #ifdef CONFIG_PPC64
 569         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 570         if (start32)
 571                 do_feature_fixups(powerpc_firmware_features,
 572                                   start32, start32 + size32);
 573 #endif /* CONFIG_PPC64 */
 574
 575         return 0;
 576 }
 577
 578 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 579                                        struct lib64_elfinfo *v64)
 580 {
 581         int i;
 582
 583         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 584                 struct vdso_patch_def *patch = &vdso_patches[i];
 585                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 586                         == patch->ftr_value;
 587                 if (!match)
 588                         continue;
 589
 590                 DBG("replacing %s with %s...\n", patch->gen_name,
 591                     patch->fix_name ? "NONE" : patch->fix_name);
 592
 593                 /*
 594                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 595                  * patch the "." symbol on 64 bits.
 596                  * It would be easy to do, but doesn't seem to be necessary,
 597                  * patching the OPD symbol is enough.
 598                  */
 599                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 600                                      patch->fix_name);
 601 #ifdef CONFIG_PPC64
 602                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 603                                      patch->fix_name);
 604 #endif /* CONFIG_PPC64 */
 605         }
 606
 607         return 0;
 608 }
 609
 610
 611 static __init int vdso_setup(void)
 612 {
 613         struct lib32_elfinfo    v32;
 614         struct lib64_elfinfo    v64;
 615
 616         v32.hdr = vdso32_kbase;
 617 #ifdef CONFIG_PPC64
 618         v64.hdr = vdso64_kbase;
 619 #endif
 620         if (vdso_do_find_sections(&v32, &v64))
 621                 return -1;
 622
 623         if (vdso_fixup_datapage(&v32, &v64))
 624                 return -1;
 625
 626         if (vdso_fixup_features(&v32, &v64))
 627                 return -1;
 628
 629         if (vdso_fixup_alt_funcs(&v32, &v64))
 630                 return -1;
 631
 632         vdso_setup_trampolines(&v32, &v64);
 633
 634         return 0;
 635 }
 636
 637 /*
 638  * Called from setup_arch to initialize the bitmap of available
 639  * syscalls in the systemcfg page
 640  */
 641 static void __init vdso_setup_syscall_map(void)
 642 {
 643         unsigned int i;
 644         extern unsigned long *sys_call_table;
 645         extern unsigned long sys_ni_syscall;
 646
 647
 648         for (i = 0; i < __NR_syscalls; i++) {
 649 #ifdef CONFIG_PPC64
 650                 if (sys_call_table[i*2] != sys_ni_syscall)
 651                         vdso_data->syscall_map_64[i >> 5] |=
 652                                 0x80000000UL >> (i & 0x1f);
 653                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 654                         vdso_data->syscall_map_32[i >> 5] |=
 655                                 0x80000000UL >> (i & 0x1f);
 656 #else /* CONFIG_PPC64 */
 657                 if (sys_call_table[i] != sys_ni_syscall)
 658                         vdso_data->syscall_map_32[i >> 5] |=
 659                                 0x80000000UL >> (i & 0x1f);
 660 #endif /* CONFIG_PPC64 */
 661         }
 662 }
 663
 664
 665 static int __init vdso_init(void)
 666 {
 667         int i;
 668
 669 #ifdef CONFIG_PPC64
 670         /*
 671          * Fill up the "systemcfg" stuff for backward compatiblity
 672          */
 673         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 674         vdso_data->version.major = SYSTEMCFG_MAJOR;
 675         vdso_data->version.minor = SYSTEMCFG_MINOR;
 676         vdso_data->processor = mfspr(SPRN_PVR);
 677         /*
 678          * Fake the old platform number for pSeries and iSeries and add
 679          * in LPAR bit if necessary
 680          */
 681         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 682         if (firmware_has_feature(FW_FEATURE_LPAR))
 683                 vdso_data->platform |= 1;
 684         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 685         vdso_data->dcache_size = ppc64_caches.dsize;
 686         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 687         vdso_data->icache_size = ppc64_caches.isize;
 688         vdso_data->icache_line_size = ppc64_caches.iline_size;
 689
 690         /*
 691          * Calculate the size of the 64 bits vDSO
 692          */
 693         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 694         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 695 #endif /* CONFIG_PPC64 */
 696
 697
 698         /*
 699          * Calculate the size of the 32 bits vDSO
 700          */
 701         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 702         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 703
 704
 705         /*
 706          * Setup the syscall map in the vDOS
 707          */
 708         vdso_setup_syscall_map();
 709
 710         /*
 711          * Initialize the vDSO images in memory, that is do necessary
 712          * fixups of vDSO symbols, locate trampolines, etc...
 713          */
 714         if (vdso_setup()) {
 715                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 716                 vdso32_pages = 0;
 717 #ifdef CONFIG_PPC64
 718                 vdso64_pages = 0;
 719 #endif
 720                 return 0;
 721         }
 722
 723         /* Make sure pages are in the correct state */
 724         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 725                                   GFP_KERNEL);
 726         BUG_ON(vdso32_pagelist == NULL);
 727         for (i = 0; i < vdso32_pages; i++) {
 728                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 729                 ClearPageReserved(pg);
 730                 get_page(pg);
 731                 vdso32_pagelist[i] = pg;
 732         }
 733         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 734         vdso32_pagelist[i] = NULL;
 735
 736 #ifdef CONFIG_PPC64
 737         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 738                                   GFP_KERNEL);
 739         BUG_ON(vdso64_pagelist == NULL);
 740         for (i = 0; i < vdso64_pages; i++) {
 741                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 742                 ClearPageReserved(pg);
 743                 get_page(pg);
 744                 vdso64_pagelist[i] = pg;
 745         }
 746         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 747         vdso64_pagelist[i] = NULL;
 748 #endif /* CONFIG_PPC64 */
 749
 750         get_page(virt_to_page(vdso_data));
 751
 752         smp_wmb();
 753         vdso_ready = 1;
 754
 755         return 0;
 756 }
 757 arch_initcall(vdso_init);
 758
 759 int in_gate_area_no_task(unsigned long addr)
 760 {
 761         return 0;
 762 }
 763
 764 int in_gate_area(struct task_struct *task, unsigned long addr)
 765 {
 766         return 0;
 767 }
 768
 769 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 770 {
 771         return NULL;
 772 }
 773