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