arch/powerpc/kernel/vdso.c

   1 /*
   2  *  linux/arch/ppc64/kernel/vdso.c
   3  *
   4  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
   5  *                       <benh@kernel.crashing.org>
   6  *
   7  *  This program is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU General Public License
   9  *  as published by the Free Software Foundation; either version
  10  *  2 of the License, or (at your option) any later version.
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/module.h>
  15 #include <linux/errno.h>
  16 #include <linux/sched.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mm.h>
  19 #include <linux/smp.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/stddef.h>
  22 #include <linux/unistd.h>
  23 #include <linux/slab.h>
  24 #include <linux/user.h>
  25 #include <linux/elf.h>
  26 #include <linux/security.h>
  27 #include <linux/bootmem.h>
  28
  29 #include <asm/pgtable.h>
  30 #include <asm/system.h>
  31 #include <asm/processor.h>
  32 #include <asm/mmu.h>
  33 #include <asm/mmu_context.h>
  34 #include <asm/lmb.h>
  35 #include <asm/machdep.h>
  36 #include <asm/cputable.h>
  37 #include <asm/sections.h>
  38 #include <asm/vdso.h>
  39 #include <asm/vdso_datapage.h>
  40
  41 #undef DEBUG
  42
  43 #ifdef DEBUG
  44 #define DBG(fmt...) printk(fmt)
  45 #else
  46 #define DBG(fmt...)
  47 #endif
  48
  49 /* Max supported size for symbol names */
  50 #define MAX_SYMNAME     64
  51
  52 extern char vdso32_start, vdso32_end;
  53 static void *vdso32_kbase = &vdso32_start;
  54 unsigned int vdso32_pages;
  55 unsigned long vdso32_sigtramp;
  56 unsigned long vdso32_rt_sigtramp;
  57
  58 #ifdef CONFIG_PPC64
  59 extern char vdso64_start, vdso64_end;
  60 static void *vdso64_kbase = &vdso64_start;
  61 unsigned int vdso64_pages;
  62 unsigned long vdso64_rt_sigtramp;
  63 #endif /* CONFIG_PPC64 */
  64
  65 /*
  66  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  67  * Once the early boot kernel code no longer needs to muck around
  68  * with it, it will become dynamically allocated
  69  */
  70 static union {
  71         struct vdso_data        data;
  72         u8                      page[PAGE_SIZE];
  73 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  74 struct vdso_data *vdso_data = &vdso_data_store.data;
  75
  76 /* Format of the patch table */
  77 struct vdso_patch_def
  78 {
  79         unsigned long   ftr_mask, ftr_value;
  80         const char      *gen_name;
  81         const char      *fix_name;
  82 };
  83
  84 /* Table of functions to patch based on the CPU type/revision
  85  *
  86  * Currently, we only change sync_dicache to do nothing on processors
  87  * with a coherent icache
  88  */
  89 static struct vdso_patch_def vdso_patches[] = {
  90         {
  91                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  92                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  93         },
  94         {
  95                 CPU_FTR_USE_TB, 0,
  96                 "__kernel_gettimeofday", NULL
  97         },
  98 };
  99
 100 /*
 101  * Some infos carried around for each of them during parsing at
 102  * boot time.
 103  */
 104 struct lib32_elfinfo
 105 {
 106         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 107         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 108         unsigned long   dynsymsize;     /* size of .dynsym section */
 109         char            *dynstr;        /* ptr to .dynstr section */
 110         unsigned long   text;           /* offset of .text section in .so */
 111 };
 112
 113 struct lib64_elfinfo
 114 {
 115         Elf64_Ehdr      *hdr;
 116         Elf64_Sym       *dynsym;
 117         unsigned long   dynsymsize;
 118         char            *dynstr;
 119         unsigned long   text;
 120 };
 121
 122
 123 #ifdef __DEBUG
 124 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 125 {
 126         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 127                page_count(pg),
 128                pg->flags);
 129         if (upg/* && pg != upg*/) {
 130                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 131                                                        << PAGE_SHIFT),
 132                        page_count(upg),
 133                        upg->flags);
 134         }
 135         printk("\n");
 136 }
 137
 138 static void dump_vdso_pages(struct vm_area_struct * vma)
 139 {
 140         int i;
 141
 142         if (!vma || test_thread_flag(TIF_32BIT)) {
 143                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 144                 for (i=0; i<vdso32_pages; i++) {
 145                         struct page *pg = virt_to_page(vdso32_kbase +
 146                                                        i*PAGE_SIZE);
 147                         struct page *upg = (vma && vma->vm_mm) ?
 148                                 follow_page(vma->vm_mm, vma->vm_start +
 149                                             i*PAGE_SIZE, 0)
 150                                 : NULL;
 151                         dump_one_vdso_page(pg, upg);
 152                 }
 153         }
 154         if (!vma || !test_thread_flag(TIF_32BIT)) {
 155                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 156                 for (i=0; i<vdso64_pages; i++) {
 157                         struct page *pg = virt_to_page(vdso64_kbase +
 158                                                        i*PAGE_SIZE);
 159                         struct page *upg = (vma && vma->vm_mm) ?
 160                                 follow_page(vma->vm_mm, vma->vm_start +
 161                                             i*PAGE_SIZE, 0)
 162                                 : NULL;
 163                         dump_one_vdso_page(pg, upg);
 164                 }
 165         }
 166 }
 167 #endif /* DEBUG */
 168
 169 /*
 170  * Keep a dummy vma_close for now, it will prevent VMA merging.
 171  */
 172 static void vdso_vma_close(struct vm_area_struct * vma)
 173 {
 174 }
 175
 176 /*
 177  * Our nopage() function, maps in the actual vDSO kernel pages, they will
 178  * be mapped read-only by do_no_page(), and eventually COW'ed, either
 179  * right away for an initial write access, or by do_wp_page().
 180  */
 181 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 182                                      unsigned long address, int *type)
 183 {
 184         unsigned long offset = address - vma->vm_start;
 185         struct page *pg;
 186 #ifdef CONFIG_PPC64
 187         void *vbase = test_thread_flag(TIF_32BIT) ?
 188                 vdso32_kbase : vdso64_kbase;
 189 #else
 190         void *vbase = vdso32_kbase;
 191 #endif
 192
 193         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
 194             current->comm, address, offset);
 195
 196         if (address < vma->vm_start || address > vma->vm_end)
 197                 return NOPAGE_SIGBUS;
 198
 199         /*
 200          * Last page is systemcfg.
 201          */
 202         if ((vma->vm_end - address) <= PAGE_SIZE)
 203                 pg = virt_to_page(vdso_data);
 204         else
 205                 pg = virt_to_page(vbase + offset);
 206
 207         get_page(pg);
 208         DBG(" ->page count: %d\n", page_count(pg));
 209
 210         return pg;
 211 }
 212
 213 static struct vm_operations_struct vdso_vmops = {
 214         .close  = vdso_vma_close,
 215         .nopage = vdso_vma_nopage,
 216 };
 217
 218 /*
 219  * This is called from binfmt_elf, we create the special vma for the
 220  * vDSO and insert it into the mm struct tree
 221  */
 222 int arch_setup_additional_pages(struct linux_binprm *bprm,
 223                                 int executable_stack)
 224 {
 225         struct mm_struct *mm = current->mm;
 226         struct vm_area_struct *vma;
 227         unsigned long vdso_pages;
 228         unsigned long vdso_base;
 229
 230 #ifdef CONFIG_PPC64
 231         if (test_thread_flag(TIF_32BIT)) {
 232                 vdso_pages = vdso32_pages;
 233                 vdso_base = VDSO32_MBASE;
 234         } else {
 235                 vdso_pages = vdso64_pages;
 236                 vdso_base = VDSO64_MBASE;
 237         }
 238 #else
 239         vdso_pages = vdso32_pages;
 240         vdso_base = VDSO32_MBASE;
 241 #endif
 242
 243         current->thread.vdso_base = 0;
 244
 245         /* vDSO has a problem and was disabled, just don't "enable" it for the
 246          * process
 247          */
 248         if (vdso_pages == 0)
 249                 return 0;
 250
 251         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
 252         if (vma == NULL)
 253                 return -ENOMEM;
 254
 255         memset(vma, 0, sizeof(*vma));
 256
 257         /* Add a page to the vdso size for the data page */
 258         vdso_pages ++;
 259
 260         /*
 261          * pick a base address for the vDSO in process space. We try to put it
 262          * at vdso_base which is the "natural" base for it, but we might fail
 263          * and end up putting it elsewhere.
 264          */
 265         vdso_base = get_unmapped_area(NULL, vdso_base,
 266                                       vdso_pages << PAGE_SHIFT, 0, 0);
 267         if (vdso_base & ~PAGE_MASK) {
 268                 kmem_cache_free(vm_area_cachep, vma);
 269                 return (int)vdso_base;
 270         }
 271
 272         current->thread.vdso_base = vdso_base;
 273
 274         vma->vm_mm = mm;
 275         vma->vm_start = current->thread.vdso_base;
 276         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 277
 278         /*
 279          * our vma flags don't have VM_WRITE so by default, the process isn't
 280          * allowed to write those pages.
 281          * gdb can break that with ptrace interface, and thus trigger COW on
 282          * those pages but it's then your responsibility to never do that on
 283          * the "data" page of the vDSO or you'll stop getting kernel updates
 284          * and your nice userland gettimeofday will be totally dead.
 285          * It's fine to use that for setting breakpoints in the vDSO code
 286          * pages though
 287          */
 288         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE |
 289                 VM_MAYEXEC | VM_RESERVED;
 290         vma->vm_flags |= mm->def_flags;
 291         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 292         vma->vm_ops = &vdso_vmops;
 293
 294         down_write(&mm->mmap_sem);
 295         if (insert_vm_struct(mm, vma)) {
 296                 up_write(&mm->mmap_sem);
 297                 kmem_cache_free(vm_area_cachep, vma);
 298                 return -ENOMEM;
 299         }
 300         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 301         up_write(&mm->mmap_sem);
 302
 303         return 0;
 304 }
 305
 306 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 307                                   unsigned long *size)
 308 {
 309         Elf32_Shdr *sechdrs;
 310         unsigned int i;
 311         char *secnames;
 312
 313         /* Grab section headers and strings so we can tell who is who */
 314         sechdrs = (void *)ehdr + ehdr->e_shoff;
 315         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 316
 317         /* Find the section they want */
 318         for (i = 1; i < ehdr->e_shnum; i++) {
 319                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 320                         if (size)
 321                                 *size = sechdrs[i].sh_size;
 322                         return (void *)ehdr + sechdrs[i].sh_offset;
 323                 }
 324         }
 325         *size = 0;
 326         return NULL;
 327 }
 328
 329 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 330                                         const char *symname)
 331 {
 332         unsigned int i;
 333         char name[MAX_SYMNAME], *c;
 334
 335         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 336                 if (lib->dynsym[i].st_name == 0)
 337                         continue;
 338                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 339                         MAX_SYMNAME);
 340                 c = strchr(name, '@');
 341                 if (c)
 342                         *c = 0;
 343                 if (strcmp(symname, name) == 0)
 344                         return &lib->dynsym[i];
 345         }
 346         return NULL;
 347 }
 348
 349 /* Note that we assume the section is .text and the symbol is relative to
 350  * the library base
 351  */
 352 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 353                                             const char *symname)
 354 {
 355         Elf32_Sym *sym = find_symbol32(lib, symname);
 356
 357         if (sym == NULL) {
 358                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 359                        symname);
 360                 return 0;
 361         }
 362         return sym->st_value - VDSO32_LBASE;
 363 }
 364
 365 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 366                                 struct lib64_elfinfo *v64,
 367                                 const char *orig, const char *fix)
 368 {
 369         Elf32_Sym *sym32_gen, *sym32_fix;
 370
 371         sym32_gen = find_symbol32(v32, orig);
 372         if (sym32_gen == NULL) {
 373                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 374                 return -1;
 375         }
 376         if (fix == NULL) {
 377                 sym32_gen->st_name = 0;
 378                 return 0;
 379         }
 380         sym32_fix = find_symbol32(v32, fix);
 381         if (sym32_fix == NULL) {
 382                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 383                 return -1;
 384         }
 385         sym32_gen->st_value = sym32_fix->st_value;
 386         sym32_gen->st_size = sym32_fix->st_size;
 387         sym32_gen->st_info = sym32_fix->st_info;
 388         sym32_gen->st_other = sym32_fix->st_other;
 389         sym32_gen->st_shndx = sym32_fix->st_shndx;
 390
 391         return 0;
 392 }
 393
 394
 395 #ifdef CONFIG_PPC64
 396
 397 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 398                                   unsigned long *size)
 399 {
 400         Elf64_Shdr *sechdrs;
 401         unsigned int i;
 402         char *secnames;
 403
 404         /* Grab section headers and strings so we can tell who is who */
 405         sechdrs = (void *)ehdr + ehdr->e_shoff;
 406         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 407
 408         /* Find the section they want */
 409         for (i = 1; i < ehdr->e_shnum; i++) {
 410                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 411                         if (size)
 412                                 *size = sechdrs[i].sh_size;
 413                         return (void *)ehdr + sechdrs[i].sh_offset;
 414                 }
 415         }
 416         if (size)
 417                 *size = 0;
 418         return NULL;
 419 }
 420
 421 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 422                                         const char *symname)
 423 {
 424         unsigned int i;
 425         char name[MAX_SYMNAME], *c;
 426
 427         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 428                 if (lib->dynsym[i].st_name == 0)
 429                         continue;
 430                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 431                         MAX_SYMNAME);
 432                 c = strchr(name, '@');
 433                 if (c)
 434                         *c = 0;
 435                 if (strcmp(symname, name) == 0)
 436                         return &lib->dynsym[i];
 437         }
 438         return NULL;
 439 }
 440
 441 /* Note that we assume the section is .text and the symbol is relative to
 442  * the library base
 443  */
 444 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 445                                             const char *symname)
 446 {
 447         Elf64_Sym *sym = find_symbol64(lib, symname);
 448
 449         if (sym == NULL) {
 450                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 451                        symname);
 452                 return 0;
 453         }
 454 #ifdef VDS64_HAS_DESCRIPTORS
 455         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 456                 VDSO64_LBASE;
 457 #else
 458         return sym->st_value - VDSO64_LBASE;
 459 #endif
 460 }
 461
 462 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 463                                 struct lib64_elfinfo *v64,
 464                                 const char *orig, const char *fix)
 465 {
 466         Elf64_Sym *sym64_gen, *sym64_fix;
 467
 468         sym64_gen = find_symbol64(v64, orig);
 469         if (sym64_gen == NULL) {
 470                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 471                 return -1;
 472         }
 473         if (fix == NULL) {
 474                 sym64_gen->st_name = 0;
 475                 return 0;
 476         }
 477         sym64_fix = find_symbol64(v64, fix);
 478         if (sym64_fix == NULL) {
 479                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 480                 return -1;
 481         }
 482         sym64_gen->st_value = sym64_fix->st_value;
 483         sym64_gen->st_size = sym64_fix->st_size;
 484         sym64_gen->st_info = sym64_fix->st_info;
 485         sym64_gen->st_other = sym64_fix->st_other;
 486         sym64_gen->st_shndx = sym64_fix->st_shndx;
 487
 488         return 0;
 489 }
 490
 491 #endif /* CONFIG_PPC64 */
 492
 493
 494 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 495                                         struct lib64_elfinfo *v64)
 496 {
 497         void *sect;
 498
 499         /*
 500          * Locate symbol tables & text section
 501          */
 502
 503         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 504         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 505         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 506                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 507                 return -1;
 508         }
 509         sect = find_section32(v32->hdr, ".text", NULL);
 510         if (sect == NULL) {
 511                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 512                 return -1;
 513         }
 514         v32->text = sect - vdso32_kbase;
 515
 516 #ifdef CONFIG_PPC64
 517         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 518         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 519         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 520                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 521                 return -1;
 522         }
 523         sect = find_section64(v64->hdr, ".text", NULL);
 524         if (sect == NULL) {
 525                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 526                 return -1;
 527         }
 528         v64->text = sect - vdso64_kbase;
 529 #endif /* CONFIG_PPC64 */
 530
 531         return 0;
 532 }
 533
 534 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 535                                           struct lib64_elfinfo *v64)
 536 {
 537         /*
 538          * Find signal trampolines
 539          */
 540
 541 #ifdef CONFIG_PPC64
 542         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 543 #endif
 544         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 545         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 546 }
 547
 548 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 549                                        struct lib64_elfinfo *v64)
 550 {
 551         Elf32_Sym *sym32;
 552 #ifdef CONFIG_PPC64
 553         Elf64_Sym *sym64;
 554
 555         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 556         if (sym64 == NULL) {
 557                 printk(KERN_ERR "vDSO64: Can't find symbol "
 558                        "__kernel_datapage_offset !\n");
 559                 return -1;
 560         }
 561         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 562                 (vdso64_pages << PAGE_SHIFT) -
 563                 (sym64->st_value - VDSO64_LBASE);
 564 #endif /* CONFIG_PPC64 */
 565
 566         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 567         if (sym32 == NULL) {
 568                 printk(KERN_ERR "vDSO32: Can't find symbol "
 569                        "__kernel_datapage_offset !\n");
 570                 return -1;
 571         }
 572         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 573                 (vdso32_pages << PAGE_SHIFT) -
 574                 (sym32->st_value - VDSO32_LBASE);
 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_alt_funcs(&v32, &v64))
 628                 return -1;
 629
 630         vdso_setup_trampolines(&v32, &v64);
 631
 632         return 0;
 633 }
 634
 635 /*
 636  * Called from setup_arch to initialize the bitmap of available
 637  * syscalls in the systemcfg page
 638  */
 639 static void __init vdso_setup_syscall_map(void)
 640 {
 641         unsigned int i;
 642         extern unsigned long *sys_call_table;
 643         extern unsigned long sys_ni_syscall;
 644
 645
 646         for (i = 0; i < __NR_syscalls; i++) {
 647 #ifdef CONFIG_PPC64
 648                 if (sys_call_table[i*2] != sys_ni_syscall)
 649                         vdso_data->syscall_map_64[i >> 5] |=
 650                                 0x80000000UL >> (i & 0x1f);
 651                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 652                         vdso_data->syscall_map_32[i >> 5] |=
 653                                 0x80000000UL >> (i & 0x1f);
 654 #else /* CONFIG_PPC64 */
 655                 if (sys_call_table[i] != sys_ni_syscall)
 656                         vdso_data->syscall_map_32[i >> 5] |=
 657                                 0x80000000UL >> (i & 0x1f);
 658 #endif /* CONFIG_PPC64 */
 659         }
 660 }
 661
 662
 663 void __init vdso_init(void)
 664 {
 665         int i;
 666
 667 #ifdef CONFIG_PPC64
 668         /*
 669          * Fill up the "systemcfg" stuff for backward compatiblity
 670          */
 671         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 672         vdso_data->version.major = SYSTEMCFG_MAJOR;
 673         vdso_data->version.minor = SYSTEMCFG_MINOR;
 674         vdso_data->processor = mfspr(SPRN_PVR);
 675         vdso_data->platform = _machine;
 676         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 677         vdso_data->dcache_size = ppc64_caches.dsize;
 678         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 679         vdso_data->icache_size = ppc64_caches.isize;
 680         vdso_data->icache_line_size = ppc64_caches.iline_size;
 681
 682         /*
 683          * Calculate the size of the 64 bits vDSO
 684          */
 685         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 686         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 687 #endif /* CONFIG_PPC64 */
 688
 689
 690         /*
 691          * Calculate the size of the 32 bits vDSO
 692          */
 693         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 694         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 695
 696
 697         /*
 698          * Setup the syscall map in the vDOS
 699          */
 700         vdso_setup_syscall_map();
 701         /*
 702          * Initialize the vDSO images in memory, that is do necessary
 703          * fixups of vDSO symbols, locate trampolines, etc...
 704          */
 705         if (vdso_setup()) {
 706                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 707                 vdso32_pages = 0;
 708 #ifdef CONFIG_PPC64
 709                 vdso64_pages = 0;
 710 #endif
 711                 return;
 712         }
 713
 714         /* Make sure pages are in the correct state */
 715         for (i = 0; i < vdso32_pages; i++) {
 716                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 717                 ClearPageReserved(pg);
 718                 get_page(pg);
 719
 720         }
 721 #ifdef CONFIG_PPC64
 722         for (i = 0; i < vdso64_pages; i++) {
 723                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 724                 ClearPageReserved(pg);
 725                 get_page(pg);
 726         }
 727 #endif /* CONFIG_PPC64 */
 728
 729         get_page(virt_to_page(vdso_data));
 730 }
 731
 732 int in_gate_area_no_task(unsigned long addr)
 733 {
 734         return 0;
 735 }
 736
 737 int in_gate_area(struct task_struct *task, unsigned long addr)
 738 {
 739         return 0;
 740 }
 741
 742 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 743 {
 744         return NULL;
 745 }
 746