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/config.h>
  12 #include <linux/module.h>
  13 #include <linux/errno.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/mm.h>
  17 #include <linux/smp.h>
  18 #include <linux/smp_lock.h>
  19 #include <linux/stddef.h>
  20 #include <linux/unistd.h>
  21 #include <linux/slab.h>
  22 #include <linux/user.h>
  23 #include <linux/elf.h>
  24 #include <linux/security.h>
  25 #include <linux/bootmem.h>
  26
  27 #include <asm/pgtable.h>
  28 #include <asm/system.h>
  29 #include <asm/processor.h>
  30 #include <asm/mmu.h>
  31 #include <asm/mmu_context.h>
  32 #include <asm/lmb.h>
  33 #include <asm/machdep.h>
  34 #include <asm/cputable.h>
  35 #include <asm/sections.h>
  36 #include <asm/firmware.h>
  37 #include <asm/vdso.h>
  38 #include <asm/vdso_datapage.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 unsigned int vdso32_pages;
  54 unsigned long vdso32_sigtramp;
  55 unsigned long vdso32_rt_sigtramp;
  56
  57 #ifdef CONFIG_PPC64
  58 extern char vdso64_start, vdso64_end;
  59 static void *vdso64_kbase = &vdso64_start;
  60 unsigned int vdso64_pages;
  61 unsigned long vdso64_rt_sigtramp;
  62 #endif /* CONFIG_PPC64 */
  63
  64 /*
  65  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  66  * Once the early boot kernel code no longer needs to muck around
  67  * with it, it will become dynamically allocated
  68  */
  69 static union {
  70         struct vdso_data        data;
  71         u8                      page[PAGE_SIZE];
  72 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  73 struct vdso_data *vdso_data = &vdso_data_store.data;
  74
  75 /* Format of the patch table */
  76 struct vdso_patch_def
  77 {
  78         unsigned long   ftr_mask, ftr_value;
  79         const char      *gen_name;
  80         const char      *fix_name;
  81 };
  82
  83 /* Table of functions to patch based on the CPU type/revision
  84  *
  85  * Currently, we only change sync_dicache to do nothing on processors
  86  * with a coherent icache
  87  */
  88 static struct vdso_patch_def vdso_patches[] = {
  89         {
  90                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  91                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  92         },
  93         {
  94                 CPU_FTR_USE_TB, 0,
  95                 "__kernel_gettimeofday", NULL
  96         },
  97 };
  98
  99 /*
 100  * Some infos carried around for each of them during parsing at
 101  * boot time.
 102  */
 103 struct lib32_elfinfo
 104 {
 105         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 106         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 107         unsigned long   dynsymsize;     /* size of .dynsym section */
 108         char            *dynstr;        /* ptr to .dynstr section */
 109         unsigned long   text;           /* offset of .text section in .so */
 110 };
 111
 112 struct lib64_elfinfo
 113 {
 114         Elf64_Ehdr      *hdr;
 115         Elf64_Sym       *dynsym;
 116         unsigned long   dynsymsize;
 117         char            *dynstr;
 118         unsigned long   text;
 119 };
 120
 121
 122 #ifdef __DEBUG
 123 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 124 {
 125         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 126                page_count(pg),
 127                pg->flags);
 128         if (upg/* && pg != upg*/) {
 129                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 130                                                        << PAGE_SHIFT),
 131                        page_count(upg),
 132                        upg->flags);
 133         }
 134         printk("\n");
 135 }
 136
 137 static void dump_vdso_pages(struct vm_area_struct * vma)
 138 {
 139         int i;
 140
 141         if (!vma || test_thread_flag(TIF_32BIT)) {
 142                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 143                 for (i=0; i<vdso32_pages; i++) {
 144                         struct page *pg = virt_to_page(vdso32_kbase +
 145                                                        i*PAGE_SIZE);
 146                         struct page *upg = (vma && vma->vm_mm) ?
 147                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 148                                 : NULL;
 149                         dump_one_vdso_page(pg, upg);
 150                 }
 151         }
 152         if (!vma || !test_thread_flag(TIF_32BIT)) {
 153                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 154                 for (i=0; i<vdso64_pages; i++) {
 155                         struct page *pg = virt_to_page(vdso64_kbase +
 156                                                        i*PAGE_SIZE);
 157                         struct page *upg = (vma && vma->vm_mm) ?
 158                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 159                                 : NULL;
 160                         dump_one_vdso_page(pg, upg);
 161                 }
 162         }
 163 }
 164 #endif /* DEBUG */
 165
 166 /*
 167  * Keep a dummy vma_close for now, it will prevent VMA merging.
 168  */
 169 static void vdso_vma_close(struct vm_area_struct * vma)
 170 {
 171 }
 172
 173 /*
 174  * Our nopage() function, maps in the actual vDSO kernel pages, they will
 175  * be mapped read-only by do_no_page(), and eventually COW'ed, either
 176  * right away for an initial write access, or by do_wp_page().
 177  */
 178 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 179                                      unsigned long address, int *type)
 180 {
 181         unsigned long offset = address - vma->vm_start;
 182         struct page *pg;
 183 #ifdef CONFIG_PPC64
 184         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
 185                 vdso64_kbase : vdso32_kbase;
 186 #else
 187         void *vbase = vdso32_kbase;
 188 #endif
 189
 190         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
 191             current->comm, address, offset);
 192
 193         if (address < vma->vm_start || address > vma->vm_end)
 194                 return NOPAGE_SIGBUS;
 195
 196         /*
 197          * Last page is systemcfg.
 198          */
 199         if ((vma->vm_end - address) <= PAGE_SIZE)
 200                 pg = virt_to_page(vdso_data);
 201         else
 202                 pg = virt_to_page(vbase + offset);
 203
 204         get_page(pg);
 205         DBG(" ->page count: %d\n", page_count(pg));
 206
 207         return pg;
 208 }
 209
 210 static struct vm_operations_struct vdso_vmops = {
 211         .close  = vdso_vma_close,
 212         .nopage = vdso_vma_nopage,
 213 };
 214
 215 /*
 216  * This is called from binfmt_elf, we create the special vma for the
 217  * vDSO and insert it into the mm struct tree
 218  */
 219 int arch_setup_additional_pages(struct linux_binprm *bprm,
 220                                 int executable_stack)
 221 {
 222         struct mm_struct *mm = current->mm;
 223         struct vm_area_struct *vma;
 224         unsigned long vdso_pages;
 225         unsigned long vdso_base;
 226
 227 #ifdef CONFIG_PPC64
 228         if (test_thread_flag(TIF_32BIT)) {
 229                 vdso_pages = vdso32_pages;
 230                 vdso_base = VDSO32_MBASE;
 231         } else {
 232                 vdso_pages = vdso64_pages;
 233                 vdso_base = VDSO64_MBASE;
 234         }
 235 #else
 236         vdso_pages = vdso32_pages;
 237         vdso_base = VDSO32_MBASE;
 238 #endif
 239
 240         current->thread.vdso_base = 0;
 241
 242         /* vDSO has a problem and was disabled, just don't "enable" it for the
 243          * process
 244          */
 245         if (vdso_pages == 0)
 246                 return 0;
 247
 248         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
 249         if (vma == NULL)
 250                 return -ENOMEM;
 251
 252         memset(vma, 0, sizeof(*vma));
 253
 254         /* Add a page to the vdso size for the data page */
 255         vdso_pages ++;
 256
 257         /*
 258          * pick a base address for the vDSO in process space. We try to put it
 259          * at vdso_base which is the "natural" base for it, but we might fail
 260          * and end up putting it elsewhere.
 261          */
 262         vdso_base = get_unmapped_area(NULL, vdso_base,
 263                                       vdso_pages << PAGE_SHIFT, 0, 0);
 264         if (vdso_base & ~PAGE_MASK) {
 265                 kmem_cache_free(vm_area_cachep, vma);
 266                 return (int)vdso_base;
 267         }
 268
 269         current->thread.vdso_base = vdso_base;
 270
 271         vma->vm_mm = mm;
 272         vma->vm_start = current->thread.vdso_base;
 273         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 274
 275         /*
 276          * our vma flags don't have VM_WRITE so by default, the process isn't
 277          * allowed to write those pages.
 278          * gdb can break that with ptrace interface, and thus trigger COW on
 279          * those pages but it's then your responsibility to never do that on
 280          * the "data" page of the vDSO or you'll stop getting kernel updates
 281          * and your nice userland gettimeofday will be totally dead.
 282          * It's fine to use that for setting breakpoints in the vDSO code
 283          * pages though
 284          */
 285         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 286         vma->vm_flags |= mm->def_flags;
 287         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 288         vma->vm_ops = &vdso_vmops;
 289
 290         down_write(&mm->mmap_sem);
 291         if (insert_vm_struct(mm, vma)) {
 292                 up_write(&mm->mmap_sem);
 293                 kmem_cache_free(vm_area_cachep, vma);
 294                 return -ENOMEM;
 295         }
 296         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 297         up_write(&mm->mmap_sem);
 298
 299         return 0;
 300 }
 301
 302 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 303                                   unsigned long *size)
 304 {
 305         Elf32_Shdr *sechdrs;
 306         unsigned int i;
 307         char *secnames;
 308
 309         /* Grab section headers and strings so we can tell who is who */
 310         sechdrs = (void *)ehdr + ehdr->e_shoff;
 311         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 312
 313         /* Find the section they want */
 314         for (i = 1; i < ehdr->e_shnum; i++) {
 315                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 316                         if (size)
 317                                 *size = sechdrs[i].sh_size;
 318                         return (void *)ehdr + sechdrs[i].sh_offset;
 319                 }
 320         }
 321         *size = 0;
 322         return NULL;
 323 }
 324
 325 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 326                                         const char *symname)
 327 {
 328         unsigned int i;
 329         char name[MAX_SYMNAME], *c;
 330
 331         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 332                 if (lib->dynsym[i].st_name == 0)
 333                         continue;
 334                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 335                         MAX_SYMNAME);
 336                 c = strchr(name, '@');
 337                 if (c)
 338                         *c = 0;
 339                 if (strcmp(symname, name) == 0)
 340                         return &lib->dynsym[i];
 341         }
 342         return NULL;
 343 }
 344
 345 /* Note that we assume the section is .text and the symbol is relative to
 346  * the library base
 347  */
 348 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 349                                             const char *symname)
 350 {
 351         Elf32_Sym *sym = find_symbol32(lib, symname);
 352
 353         if (sym == NULL) {
 354                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 355                        symname);
 356                 return 0;
 357         }
 358         return sym->st_value - VDSO32_LBASE;
 359 }
 360
 361 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 362                                 struct lib64_elfinfo *v64,
 363                                 const char *orig, const char *fix)
 364 {
 365         Elf32_Sym *sym32_gen, *sym32_fix;
 366
 367         sym32_gen = find_symbol32(v32, orig);
 368         if (sym32_gen == NULL) {
 369                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 370                 return -1;
 371         }
 372         if (fix == NULL) {
 373                 sym32_gen->st_name = 0;
 374                 return 0;
 375         }
 376         sym32_fix = find_symbol32(v32, fix);
 377         if (sym32_fix == NULL) {
 378                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 379                 return -1;
 380         }
 381         sym32_gen->st_value = sym32_fix->st_value;
 382         sym32_gen->st_size = sym32_fix->st_size;
 383         sym32_gen->st_info = sym32_fix->st_info;
 384         sym32_gen->st_other = sym32_fix->st_other;
 385         sym32_gen->st_shndx = sym32_fix->st_shndx;
 386
 387         return 0;
 388 }
 389
 390
 391 #ifdef CONFIG_PPC64
 392
 393 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 394                                   unsigned long *size)
 395 {
 396         Elf64_Shdr *sechdrs;
 397         unsigned int i;
 398         char *secnames;
 399
 400         /* Grab section headers and strings so we can tell who is who */
 401         sechdrs = (void *)ehdr + ehdr->e_shoff;
 402         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 403
 404         /* Find the section they want */
 405         for (i = 1; i < ehdr->e_shnum; i++) {
 406                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 407                         if (size)
 408                                 *size = sechdrs[i].sh_size;
 409                         return (void *)ehdr + sechdrs[i].sh_offset;
 410                 }
 411         }
 412         if (size)
 413                 *size = 0;
 414         return NULL;
 415 }
 416
 417 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 418                                         const char *symname)
 419 {
 420         unsigned int i;
 421         char name[MAX_SYMNAME], *c;
 422
 423         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 424                 if (lib->dynsym[i].st_name == 0)
 425                         continue;
 426                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 427                         MAX_SYMNAME);
 428                 c = strchr(name, '@');
 429                 if (c)
 430                         *c = 0;
 431                 if (strcmp(symname, name) == 0)
 432                         return &lib->dynsym[i];
 433         }
 434         return NULL;
 435 }
 436
 437 /* Note that we assume the section is .text and the symbol is relative to
 438  * the library base
 439  */
 440 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 441                                             const char *symname)
 442 {
 443         Elf64_Sym *sym = find_symbol64(lib, symname);
 444
 445         if (sym == NULL) {
 446                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 447                        symname);
 448                 return 0;
 449         }
 450 #ifdef VDS64_HAS_DESCRIPTORS
 451         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 452                 VDSO64_LBASE;
 453 #else
 454         return sym->st_value - VDSO64_LBASE;
 455 #endif
 456 }
 457
 458 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 459                                 struct lib64_elfinfo *v64,
 460                                 const char *orig, const char *fix)
 461 {
 462         Elf64_Sym *sym64_gen, *sym64_fix;
 463
 464         sym64_gen = find_symbol64(v64, orig);
 465         if (sym64_gen == NULL) {
 466                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 467                 return -1;
 468         }
 469         if (fix == NULL) {
 470                 sym64_gen->st_name = 0;
 471                 return 0;
 472         }
 473         sym64_fix = find_symbol64(v64, fix);
 474         if (sym64_fix == NULL) {
 475                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 476                 return -1;
 477         }
 478         sym64_gen->st_value = sym64_fix->st_value;
 479         sym64_gen->st_size = sym64_fix->st_size;
 480         sym64_gen->st_info = sym64_fix->st_info;
 481         sym64_gen->st_other = sym64_fix->st_other;
 482         sym64_gen->st_shndx = sym64_fix->st_shndx;
 483
 484         return 0;
 485 }
 486
 487 #endif /* CONFIG_PPC64 */
 488
 489
 490 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 491                                         struct lib64_elfinfo *v64)
 492 {
 493         void *sect;
 494
 495         /*
 496          * Locate symbol tables & text section
 497          */
 498
 499         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 500         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 501         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 502                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 503                 return -1;
 504         }
 505         sect = find_section32(v32->hdr, ".text", NULL);
 506         if (sect == NULL) {
 507                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 508                 return -1;
 509         }
 510         v32->text = sect - vdso32_kbase;
 511
 512 #ifdef CONFIG_PPC64
 513         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 514         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 515         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 516                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 517                 return -1;
 518         }
 519         sect = find_section64(v64->hdr, ".text", NULL);
 520         if (sect == NULL) {
 521                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 522                 return -1;
 523         }
 524         v64->text = sect - vdso64_kbase;
 525 #endif /* CONFIG_PPC64 */
 526
 527         return 0;
 528 }
 529
 530 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 531                                           struct lib64_elfinfo *v64)
 532 {
 533         /*
 534          * Find signal trampolines
 535          */
 536
 537 #ifdef CONFIG_PPC64
 538         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 539 #endif
 540         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 541         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 542 }
 543
 544 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 545                                        struct lib64_elfinfo *v64)
 546 {
 547         Elf32_Sym *sym32;
 548 #ifdef CONFIG_PPC64
 549         Elf64_Sym *sym64;
 550
 551         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 552         if (sym64 == NULL) {
 553                 printk(KERN_ERR "vDSO64: Can't find symbol "
 554                        "__kernel_datapage_offset !\n");
 555                 return -1;
 556         }
 557         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 558                 (vdso64_pages << PAGE_SHIFT) -
 559                 (sym64->st_value - VDSO64_LBASE);
 560 #endif /* CONFIG_PPC64 */
 561
 562         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 563         if (sym32 == NULL) {
 564                 printk(KERN_ERR "vDSO32: Can't find symbol "
 565                        "__kernel_datapage_offset !\n");
 566                 return -1;
 567         }
 568         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 569                 (vdso32_pages << PAGE_SHIFT) -
 570                 (sym32->st_value - VDSO32_LBASE);
 571
 572         return 0;
 573 }
 574
 575 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 576                                        struct lib64_elfinfo *v64)
 577 {
 578         int i;
 579
 580         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 581                 struct vdso_patch_def *patch = &vdso_patches[i];
 582                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 583                         == patch->ftr_value;
 584                 if (!match)
 585                         continue;
 586
 587                 DBG("replacing %s with %s...\n", patch->gen_name,
 588                     patch->fix_name ? "NONE" : patch->fix_name);
 589
 590                 /*
 591                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 592                  * patch the "." symbol on 64 bits.
 593                  * It would be easy to do, but doesn't seem to be necessary,
 594                  * patching the OPD symbol is enough.
 595                  */
 596                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 597                                      patch->fix_name);
 598 #ifdef CONFIG_PPC64
 599                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 600                                      patch->fix_name);
 601 #endif /* CONFIG_PPC64 */
 602         }
 603
 604         return 0;
 605 }
 606
 607
 608 static __init int vdso_setup(void)
 609 {
 610         struct lib32_elfinfo    v32;
 611         struct lib64_elfinfo    v64;
 612
 613         v32.hdr = vdso32_kbase;
 614 #ifdef CONFIG_PPC64
 615         v64.hdr = vdso64_kbase;
 616 #endif
 617         if (vdso_do_find_sections(&v32, &v64))
 618                 return -1;
 619
 620         if (vdso_fixup_datapage(&v32, &v64))
 621                 return -1;
 622
 623         if (vdso_fixup_alt_funcs(&v32, &v64))
 624                 return -1;
 625
 626         vdso_setup_trampolines(&v32, &v64);
 627
 628         return 0;
 629 }
 630
 631 /*
 632  * Called from setup_arch to initialize the bitmap of available
 633  * syscalls in the systemcfg page
 634  */
 635 static void __init vdso_setup_syscall_map(void)
 636 {
 637         unsigned int i;
 638         extern unsigned long *sys_call_table;
 639         extern unsigned long sys_ni_syscall;
 640
 641
 642         for (i = 0; i < __NR_syscalls; i++) {
 643 #ifdef CONFIG_PPC64
 644                 if (sys_call_table[i*2] != sys_ni_syscall)
 645                         vdso_data->syscall_map_64[i >> 5] |=
 646                                 0x80000000UL >> (i & 0x1f);
 647                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 648                         vdso_data->syscall_map_32[i >> 5] |=
 649                                 0x80000000UL >> (i & 0x1f);
 650 #else /* CONFIG_PPC64 */
 651                 if (sys_call_table[i] != sys_ni_syscall)
 652                         vdso_data->syscall_map_32[i >> 5] |=
 653                                 0x80000000UL >> (i & 0x1f);
 654 #endif /* CONFIG_PPC64 */
 655         }
 656 }
 657
 658
 659 void __init vdso_init(void)
 660 {
 661         int i;
 662
 663 #ifdef CONFIG_PPC64
 664         /*
 665          * Fill up the "systemcfg" stuff for backward compatiblity
 666          */
 667         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 668         vdso_data->version.major = SYSTEMCFG_MAJOR;
 669         vdso_data->version.minor = SYSTEMCFG_MINOR;
 670         vdso_data->processor = mfspr(SPRN_PVR);
 671         /*
 672          * Fake the old platform number for pSeries and iSeries and add
 673          * in LPAR bit if necessary
 674          */
 675         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 676         if (firmware_has_feature(FW_FEATURE_LPAR))
 677                 vdso_data->platform |= 1;
 678         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 679         vdso_data->dcache_size = ppc64_caches.dsize;
 680         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 681         vdso_data->icache_size = ppc64_caches.isize;
 682         vdso_data->icache_line_size = ppc64_caches.iline_size;
 683
 684         /*
 685          * Calculate the size of the 64 bits vDSO
 686          */
 687         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 688         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 689 #endif /* CONFIG_PPC64 */
 690
 691
 692         /*
 693          * Calculate the size of the 32 bits vDSO
 694          */
 695         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 696         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 697
 698
 699         /*
 700          * Setup the syscall map in the vDOS
 701          */
 702         vdso_setup_syscall_map();
 703         /*
 704          * Initialize the vDSO images in memory, that is do necessary
 705          * fixups of vDSO symbols, locate trampolines, etc...
 706          */
 707         if (vdso_setup()) {
 708                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 709                 vdso32_pages = 0;
 710 #ifdef CONFIG_PPC64
 711                 vdso64_pages = 0;
 712 #endif
 713                 return;
 714         }
 715
 716         /* Make sure pages are in the correct state */
 717         for (i = 0; i < vdso32_pages; i++) {
 718                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 719                 ClearPageReserved(pg);
 720                 get_page(pg);
 721
 722         }
 723 #ifdef CONFIG_PPC64
 724         for (i = 0; i < vdso64_pages; i++) {
 725                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 726                 ClearPageReserved(pg);
 727                 get_page(pg);
 728         }
 729 #endif /* CONFIG_PPC64 */
 730
 731         get_page(virt_to_page(vdso_data));
 732 }
 733
 734 int in_gate_area_no_task(unsigned long addr)
 735 {
 736         return 0;
 737 }
 738
 739 int in_gate_area(struct task_struct *task, unsigned long addr)
 740 {
 741         return 0;
 742 }
 743
 744 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 745 {
 746         return NULL;
 747 }
 748