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         int rc;
 227
 228 #ifdef CONFIG_PPC64
 229         if (test_thread_flag(TIF_32BIT)) {
 230                 vdso_pages = vdso32_pages;
 231                 vdso_base = VDSO32_MBASE;
 232         } else {
 233                 vdso_pages = vdso64_pages;
 234                 vdso_base = VDSO64_MBASE;
 235         }
 236 #else
 237         vdso_pages = vdso32_pages;
 238         vdso_base = VDSO32_MBASE;
 239 #endif
 240
 241         current->mm->context.vdso_base = 0;
 242
 243         /* vDSO has a problem and was disabled, just don't "enable" it for the
 244          * process
 245          */
 246         if (vdso_pages == 0)
 247                 return 0;
 248         /* Add a page to the vdso size for the data page */
 249         vdso_pages ++;
 250
 251         /*
 252          * pick a base address for the vDSO in process space. We try to put it
 253          * at vdso_base which is the "natural" base for it, but we might fail
 254          * and end up putting it elsewhere.
 255          */
 256         down_write(&mm->mmap_sem);
 257         vdso_base = get_unmapped_area(NULL, vdso_base,
 258                                       vdso_pages << PAGE_SHIFT, 0, 0);
 259         if (IS_ERR_VALUE(vdso_base)) {
 260                 rc = vdso_base;
 261                 goto fail_mmapsem;
 262         }
 263
 264
 265         /* Allocate a VMA structure and fill it up */
 266         vma = kmem_cache_zalloc(vm_area_cachep, SLAB_KERNEL);
 267         if (vma == NULL) {
 268                 rc = -ENOMEM;
 269                 goto fail_mmapsem;
 270         }
 271         vma->vm_mm = mm;
 272         vma->vm_start = 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         /* Insert new VMA */
 291         rc = insert_vm_struct(mm, vma);
 292         if (rc)
 293                 goto fail_vma;
 294
 295         /* Put vDSO base into mm struct and account for memory usage */
 296         current->mm->context.vdso_base = vdso_base;
 297         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 298         up_write(&mm->mmap_sem);
 299         return 0;
 300
 301  fail_vma:
 302         kmem_cache_free(vm_area_cachep, vma);
 303  fail_mmapsem:
 304         up_write(&mm->mmap_sem);
 305         return rc;
 306 }
 307
 308 const char *arch_vma_name(struct vm_area_struct *vma)
 309 {
 310         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 311                 return "[vdso]";
 312         return NULL;
 313 }
 314
 315
 316
 317 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 318                                   unsigned long *size)
 319 {
 320         Elf32_Shdr *sechdrs;
 321         unsigned int i;
 322         char *secnames;
 323
 324         /* Grab section headers and strings so we can tell who is who */
 325         sechdrs = (void *)ehdr + ehdr->e_shoff;
 326         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 327
 328         /* Find the section they want */
 329         for (i = 1; i < ehdr->e_shnum; i++) {
 330                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 331                         if (size)
 332                                 *size = sechdrs[i].sh_size;
 333                         return (void *)ehdr + sechdrs[i].sh_offset;
 334                 }
 335         }
 336         *size = 0;
 337         return NULL;
 338 }
 339
 340 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 341                                         const char *symname)
 342 {
 343         unsigned int i;
 344         char name[MAX_SYMNAME], *c;
 345
 346         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 347                 if (lib->dynsym[i].st_name == 0)
 348                         continue;
 349                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 350                         MAX_SYMNAME);
 351                 c = strchr(name, '@');
 352                 if (c)
 353                         *c = 0;
 354                 if (strcmp(symname, name) == 0)
 355                         return &lib->dynsym[i];
 356         }
 357         return NULL;
 358 }
 359
 360 /* Note that we assume the section is .text and the symbol is relative to
 361  * the library base
 362  */
 363 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 364                                             const char *symname)
 365 {
 366         Elf32_Sym *sym = find_symbol32(lib, symname);
 367
 368         if (sym == NULL) {
 369                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 370                        symname);
 371                 return 0;
 372         }
 373         return sym->st_value - VDSO32_LBASE;
 374 }
 375
 376 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 377                                 struct lib64_elfinfo *v64,
 378                                 const char *orig, const char *fix)
 379 {
 380         Elf32_Sym *sym32_gen, *sym32_fix;
 381
 382         sym32_gen = find_symbol32(v32, orig);
 383         if (sym32_gen == NULL) {
 384                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 385                 return -1;
 386         }
 387         if (fix == NULL) {
 388                 sym32_gen->st_name = 0;
 389                 return 0;
 390         }
 391         sym32_fix = find_symbol32(v32, fix);
 392         if (sym32_fix == NULL) {
 393                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 394                 return -1;
 395         }
 396         sym32_gen->st_value = sym32_fix->st_value;
 397         sym32_gen->st_size = sym32_fix->st_size;
 398         sym32_gen->st_info = sym32_fix->st_info;
 399         sym32_gen->st_other = sym32_fix->st_other;
 400         sym32_gen->st_shndx = sym32_fix->st_shndx;
 401
 402         return 0;
 403 }
 404
 405
 406 #ifdef CONFIG_PPC64
 407
 408 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 409                                   unsigned long *size)
 410 {
 411         Elf64_Shdr *sechdrs;
 412         unsigned int i;
 413         char *secnames;
 414
 415         /* Grab section headers and strings so we can tell who is who */
 416         sechdrs = (void *)ehdr + ehdr->e_shoff;
 417         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 418
 419         /* Find the section they want */
 420         for (i = 1; i < ehdr->e_shnum; i++) {
 421                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 422                         if (size)
 423                                 *size = sechdrs[i].sh_size;
 424                         return (void *)ehdr + sechdrs[i].sh_offset;
 425                 }
 426         }
 427         if (size)
 428                 *size = 0;
 429         return NULL;
 430 }
 431
 432 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 433                                         const char *symname)
 434 {
 435         unsigned int i;
 436         char name[MAX_SYMNAME], *c;
 437
 438         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 439                 if (lib->dynsym[i].st_name == 0)
 440                         continue;
 441                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 442                         MAX_SYMNAME);
 443                 c = strchr(name, '@');
 444                 if (c)
 445                         *c = 0;
 446                 if (strcmp(symname, name) == 0)
 447                         return &lib->dynsym[i];
 448         }
 449         return NULL;
 450 }
 451
 452 /* Note that we assume the section is .text and the symbol is relative to
 453  * the library base
 454  */
 455 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 456                                             const char *symname)
 457 {
 458         Elf64_Sym *sym = find_symbol64(lib, symname);
 459
 460         if (sym == NULL) {
 461                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 462                        symname);
 463                 return 0;
 464         }
 465 #ifdef VDS64_HAS_DESCRIPTORS
 466         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 467                 VDSO64_LBASE;
 468 #else
 469         return sym->st_value - VDSO64_LBASE;
 470 #endif
 471 }
 472
 473 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 474                                 struct lib64_elfinfo *v64,
 475                                 const char *orig, const char *fix)
 476 {
 477         Elf64_Sym *sym64_gen, *sym64_fix;
 478
 479         sym64_gen = find_symbol64(v64, orig);
 480         if (sym64_gen == NULL) {
 481                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 482                 return -1;
 483         }
 484         if (fix == NULL) {
 485                 sym64_gen->st_name = 0;
 486                 return 0;
 487         }
 488         sym64_fix = find_symbol64(v64, fix);
 489         if (sym64_fix == NULL) {
 490                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 491                 return -1;
 492         }
 493         sym64_gen->st_value = sym64_fix->st_value;
 494         sym64_gen->st_size = sym64_fix->st_size;
 495         sym64_gen->st_info = sym64_fix->st_info;
 496         sym64_gen->st_other = sym64_fix->st_other;
 497         sym64_gen->st_shndx = sym64_fix->st_shndx;
 498
 499         return 0;
 500 }
 501
 502 #endif /* CONFIG_PPC64 */
 503
 504
 505 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 506                                         struct lib64_elfinfo *v64)
 507 {
 508         void *sect;
 509
 510         /*
 511          * Locate symbol tables & text section
 512          */
 513
 514         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 515         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 516         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 517                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 518                 return -1;
 519         }
 520         sect = find_section32(v32->hdr, ".text", NULL);
 521         if (sect == NULL) {
 522                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 523                 return -1;
 524         }
 525         v32->text = sect - vdso32_kbase;
 526
 527 #ifdef CONFIG_PPC64
 528         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 529         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 530         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 531                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 532                 return -1;
 533         }
 534         sect = find_section64(v64->hdr, ".text", NULL);
 535         if (sect == NULL) {
 536                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 537                 return -1;
 538         }
 539         v64->text = sect - vdso64_kbase;
 540 #endif /* CONFIG_PPC64 */
 541
 542         return 0;
 543 }
 544
 545 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 546                                           struct lib64_elfinfo *v64)
 547 {
 548         /*
 549          * Find signal trampolines
 550          */
 551
 552 #ifdef CONFIG_PPC64
 553         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 554 #endif
 555         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 556         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 557 }
 558
 559 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 560                                        struct lib64_elfinfo *v64)
 561 {
 562         Elf32_Sym *sym32;
 563 #ifdef CONFIG_PPC64
 564         Elf64_Sym *sym64;
 565
 566         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 567         if (sym64 == NULL) {
 568                 printk(KERN_ERR "vDSO64: Can't find symbol "
 569                        "__kernel_datapage_offset !\n");
 570                 return -1;
 571         }
 572         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 573                 (vdso64_pages << PAGE_SHIFT) -
 574                 (sym64->st_value - VDSO64_LBASE);
 575 #endif /* CONFIG_PPC64 */
 576
 577         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 578         if (sym32 == NULL) {
 579                 printk(KERN_ERR "vDSO32: Can't find symbol "
 580                        "__kernel_datapage_offset !\n");
 581                 return -1;
 582         }
 583         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 584                 (vdso32_pages << PAGE_SHIFT) -
 585                 (sym32->st_value - VDSO32_LBASE);
 586
 587         return 0;
 588 }
 589
 590 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 591                                        struct lib64_elfinfo *v64)
 592 {
 593         int i;
 594
 595         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 596                 struct vdso_patch_def *patch = &vdso_patches[i];
 597                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 598                         == patch->ftr_value;
 599                 if (!match)
 600                         continue;
 601
 602                 DBG("replacing %s with %s...\n", patch->gen_name,
 603                     patch->fix_name ? "NONE" : patch->fix_name);
 604
 605                 /*
 606                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 607                  * patch the "." symbol on 64 bits.
 608                  * It would be easy to do, but doesn't seem to be necessary,
 609                  * patching the OPD symbol is enough.
 610                  */
 611                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 612                                      patch->fix_name);
 613 #ifdef CONFIG_PPC64
 614                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 615                                      patch->fix_name);
 616 #endif /* CONFIG_PPC64 */
 617         }
 618
 619         return 0;
 620 }
 621
 622
 623 static __init int vdso_setup(void)
 624 {
 625         struct lib32_elfinfo    v32;
 626         struct lib64_elfinfo    v64;
 627
 628         v32.hdr = vdso32_kbase;
 629 #ifdef CONFIG_PPC64
 630         v64.hdr = vdso64_kbase;
 631 #endif
 632         if (vdso_do_find_sections(&v32, &v64))
 633                 return -1;
 634
 635         if (vdso_fixup_datapage(&v32, &v64))
 636                 return -1;
 637
 638         if (vdso_fixup_alt_funcs(&v32, &v64))
 639                 return -1;
 640
 641         vdso_setup_trampolines(&v32, &v64);
 642
 643         return 0;
 644 }
 645
 646 /*
 647  * Called from setup_arch to initialize the bitmap of available
 648  * syscalls in the systemcfg page
 649  */
 650 static void __init vdso_setup_syscall_map(void)
 651 {
 652         unsigned int i;
 653         extern unsigned long *sys_call_table;
 654         extern unsigned long sys_ni_syscall;
 655
 656
 657         for (i = 0; i < __NR_syscalls; i++) {
 658 #ifdef CONFIG_PPC64
 659                 if (sys_call_table[i*2] != sys_ni_syscall)
 660                         vdso_data->syscall_map_64[i >> 5] |=
 661                                 0x80000000UL >> (i & 0x1f);
 662                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 663                         vdso_data->syscall_map_32[i >> 5] |=
 664                                 0x80000000UL >> (i & 0x1f);
 665 #else /* CONFIG_PPC64 */
 666                 if (sys_call_table[i] != sys_ni_syscall)
 667                         vdso_data->syscall_map_32[i >> 5] |=
 668                                 0x80000000UL >> (i & 0x1f);
 669 #endif /* CONFIG_PPC64 */
 670         }
 671 }
 672
 673
 674 void __init vdso_init(void)
 675 {
 676         int i;
 677
 678 #ifdef CONFIG_PPC64
 679         /*
 680          * Fill up the "systemcfg" stuff for backward compatiblity
 681          */
 682         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 683         vdso_data->version.major = SYSTEMCFG_MAJOR;
 684         vdso_data->version.minor = SYSTEMCFG_MINOR;
 685         vdso_data->processor = mfspr(SPRN_PVR);
 686         /*
 687          * Fake the old platform number for pSeries and iSeries and add
 688          * in LPAR bit if necessary
 689          */
 690         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 691         if (firmware_has_feature(FW_FEATURE_LPAR))
 692                 vdso_data->platform |= 1;
 693         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 694         vdso_data->dcache_size = ppc64_caches.dsize;
 695         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 696         vdso_data->icache_size = ppc64_caches.isize;
 697         vdso_data->icache_line_size = ppc64_caches.iline_size;
 698
 699         /*
 700          * Calculate the size of the 64 bits vDSO
 701          */
 702         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 703         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 704 #endif /* CONFIG_PPC64 */
 705
 706
 707         /*
 708          * Calculate the size of the 32 bits vDSO
 709          */
 710         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 711         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 712
 713
 714         /*
 715          * Setup the syscall map in the vDOS
 716          */
 717         vdso_setup_syscall_map();
 718         /*
 719          * Initialize the vDSO images in memory, that is do necessary
 720          * fixups of vDSO symbols, locate trampolines, etc...
 721          */
 722         if (vdso_setup()) {
 723                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 724                 vdso32_pages = 0;
 725 #ifdef CONFIG_PPC64
 726                 vdso64_pages = 0;
 727 #endif
 728                 return;
 729         }
 730
 731         /* Make sure pages are in the correct state */
 732         for (i = 0; i < vdso32_pages; i++) {
 733                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 734                 ClearPageReserved(pg);
 735                 get_page(pg);
 736
 737         }
 738 #ifdef CONFIG_PPC64
 739         for (i = 0; i < vdso64_pages; i++) {
 740                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 741                 ClearPageReserved(pg);
 742                 get_page(pg);
 743         }
 744 #endif /* CONFIG_PPC64 */
 745
 746         get_page(virt_to_page(vdso_data));
 747 }
 748
 749 int in_gate_area_no_task(unsigned long addr)
 750 {
 751         return 0;
 752 }
 753
 754 int in_gate_area(struct task_struct *task, unsigned long addr)
 755 {
 756         return 0;
 757 }
 758
 759 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 760 {
 761         return NULL;
 762 }
 763