arch/powerpc/kernel/vdso.c

   1
   2 /*
   3  *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
   4  *                       <benh@kernel.crashing.org>
   5  *
   6  *  This program is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU General Public License
   8  *  as published by the Free Software Foundation; either version
   9  *  2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/errno.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/smp.h>
  17 #include <linux/stddef.h>
  18 #include <linux/unistd.h>
  19 #include <linux/slab.h>
  20 #include <linux/user.h>
  21 #include <linux/elf.h>
  22 #include <linux/security.h>
  23 #include <linux/bootmem.h>
  24 #include <linux/memblock.h>
  25
  26 #include <asm/pgtable.h>
  27 #include <asm/system.h>
  28 #include <asm/processor.h>
  29 #include <asm/mmu.h>
  30 #include <asm/mmu_context.h>
  31 #include <asm/prom.h>
  32 #include <asm/machdep.h>
  33 #include <asm/cputable.h>
  34 #include <asm/sections.h>
  35 #include <asm/firmware.h>
  36 #include <asm/vdso.h>
  37 #include <asm/vdso_datapage.h>
  38
  39 #include "setup.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 /* The alignment of the vDSO */
  53 #define VDSO_ALIGNMENT  (1 << 16)
  54
  55 extern char vdso32_start, vdso32_end;
  56 static void *vdso32_kbase = &vdso32_start;
  57 static unsigned int vdso32_pages;
  58 static struct page **vdso32_pagelist;
  59 unsigned long vdso32_sigtramp;
  60 unsigned long vdso32_rt_sigtramp;
  61
  62 #ifdef CONFIG_PPC64
  63 extern char vdso64_start, vdso64_end;
  64 static void *vdso64_kbase = &vdso64_start;
  65 static unsigned int vdso64_pages;
  66 static struct page **vdso64_pagelist;
  67 unsigned long vdso64_rt_sigtramp;
  68 #endif /* CONFIG_PPC64 */
  69
  70 static int vdso_ready;
  71
  72 /*
  73  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  74  * Once the early boot kernel code no longer needs to muck around
  75  * with it, it will become dynamically allocated
  76  */
  77 static union {
  78         struct vdso_data        data;
  79         u8                      page[PAGE_SIZE];
  80 } vdso_data_store __page_aligned_data;
  81 struct vdso_data *vdso_data = &vdso_data_store.data;
  82
  83 /* Format of the patch table */
  84 struct vdso_patch_def
  85 {
  86         unsigned long   ftr_mask, ftr_value;
  87         const char      *gen_name;
  88         const char      *fix_name;
  89 };
  90
  91 /* Table of functions to patch based on the CPU type/revision
  92  *
  93  * Currently, we only change sync_dicache to do nothing on processors
  94  * with a coherent icache
  95  */
  96 static struct vdso_patch_def vdso_patches[] = {
  97         {
  98                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  99                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
 100         },
 101         {
 102                 CPU_FTR_USE_TB, 0,
 103                 "__kernel_gettimeofday", NULL
 104         },
 105         {
 106                 CPU_FTR_USE_TB, 0,
 107                 "__kernel_clock_gettime", NULL
 108         },
 109         {
 110                 CPU_FTR_USE_TB, 0,
 111                 "__kernel_clock_getres", NULL
 112         },
 113         {
 114                 CPU_FTR_USE_TB, 0,
 115                 "__kernel_get_tbfreq", NULL
 116         },
 117 };
 118
 119 /*
 120  * Some infos carried around for each of them during parsing at
 121  * boot time.
 122  */
 123 struct lib32_elfinfo
 124 {
 125         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 126         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 127         unsigned long   dynsymsize;     /* size of .dynsym section */
 128         char            *dynstr;        /* ptr to .dynstr section */
 129         unsigned long   text;           /* offset of .text section in .so */
 130 };
 131
 132 struct lib64_elfinfo
 133 {
 134         Elf64_Ehdr      *hdr;
 135         Elf64_Sym       *dynsym;
 136         unsigned long   dynsymsize;
 137         char            *dynstr;
 138         unsigned long   text;
 139 };
 140
 141
 142 #ifdef __DEBUG
 143 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 144 {
 145         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 146                page_count(pg),
 147                pg->flags);
 148         if (upg && !IS_ERR(upg) /* && pg != upg*/) {
 149                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 150                                                        << PAGE_SHIFT),
 151                        page_count(upg),
 152                        upg->flags);
 153         }
 154         printk("\n");
 155 }
 156
 157 static void dump_vdso_pages(struct vm_area_struct * vma)
 158 {
 159         int i;
 160
 161         if (!vma || is_32bit_task()) {
 162                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 163                 for (i=0; i<vdso32_pages; i++) {
 164                         struct page *pg = virt_to_page(vdso32_kbase +
 165                                                        i*PAGE_SIZE);
 166                         struct page *upg = (vma && vma->vm_mm) ?
 167                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 168                                 : NULL;
 169                         dump_one_vdso_page(pg, upg);
 170                 }
 171         }
 172         if (!vma || !is_32bit_task()) {
 173                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 174                 for (i=0; i<vdso64_pages; i++) {
 175                         struct page *pg = virt_to_page(vdso64_kbase +
 176                                                        i*PAGE_SIZE);
 177                         struct page *upg = (vma && vma->vm_mm) ?
 178                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 179                                 : NULL;
 180                         dump_one_vdso_page(pg, upg);
 181                 }
 182         }
 183 }
 184 #endif /* DEBUG */
 185
 186 /*
 187  * This is called from binfmt_elf, we create the special vma for the
 188  * vDSO and insert it into the mm struct tree
 189  */
 190 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 191 {
 192         struct mm_struct *mm = current->mm;
 193         struct page **vdso_pagelist;
 194         unsigned long vdso_pages;
 195         unsigned long vdso_base;
 196         int rc;
 197
 198         if (!vdso_ready)
 199                 return 0;
 200
 201 #ifdef CONFIG_PPC64
 202         if (is_32bit_task()) {
 203                 vdso_pagelist = vdso32_pagelist;
 204                 vdso_pages = vdso32_pages;
 205                 vdso_base = VDSO32_MBASE;
 206         } else {
 207                 vdso_pagelist = vdso64_pagelist;
 208                 vdso_pages = vdso64_pages;
 209                 /*
 210                  * On 64bit we don't have a preferred map address. This
 211                  * allows get_unmapped_area to find an area near other mmaps
 212                  * and most likely share a SLB entry.
 213                  */
 214                 vdso_base = 0;
 215         }
 216 #else
 217         vdso_pagelist = vdso32_pagelist;
 218         vdso_pages = vdso32_pages;
 219         vdso_base = VDSO32_MBASE;
 220 #endif
 221
 222         current->mm->context.vdso_base = 0;
 223
 224         /* vDSO has a problem and was disabled, just don't "enable" it for the
 225          * process
 226          */
 227         if (vdso_pages == 0)
 228                 return 0;
 229         /* Add a page to the vdso size for the data page */
 230         vdso_pages ++;
 231
 232         /*
 233          * pick a base address for the vDSO in process space. We try to put it
 234          * at vdso_base which is the "natural" base for it, but we might fail
 235          * and end up putting it elsewhere.
 236          * Add enough to the size so that the result can be aligned.
 237          */
 238         down_write(&mm->mmap_sem);
 239         vdso_base = get_unmapped_area(NULL, vdso_base,
 240                                       (vdso_pages << PAGE_SHIFT) +
 241                                       ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 242                                       0, 0);
 243         if (IS_ERR_VALUE(vdso_base)) {
 244                 rc = vdso_base;
 245                 goto fail_mmapsem;
 246         }
 247
 248         /* Add required alignment. */
 249         vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
 250
 251         /*
 252          * Put vDSO base into mm struct. We need to do this before calling
 253          * install_special_mapping or the perf counter mmap tracking code
 254          * will fail to recognise it as a vDSO (since arch_vma_name fails).
 255          */
 256         current->mm->context.vdso_base = vdso_base;
 257
 258         /*
 259          * our vma flags don't have VM_WRITE so by default, the process isn't
 260          * allowed to write those pages.
 261          * gdb can break that with ptrace interface, and thus trigger COW on
 262          * those pages but it's then your responsibility to never do that on
 263          * the "data" page of the vDSO or you'll stop getting kernel updates
 264          * and your nice userland gettimeofday will be totally dead.
 265          * It's fine to use that for setting breakpoints in the vDSO code
 266          * pages though
 267          *
 268          * Make sure the vDSO gets into every core dump.
 269          * Dumping its contents makes post-mortem fully interpretable later
 270          * without matching up the same kernel and hardware config to see
 271          * what PC values meant.
 272          */
 273         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 274                                      VM_READ|VM_EXEC|
 275                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
 276                                      VM_ALWAYSDUMP,
 277                                      vdso_pagelist);
 278         if (rc) {
 279                 current->mm->context.vdso_base = 0;
 280                 goto fail_mmapsem;
 281         }
 282
 283         up_write(&mm->mmap_sem);
 284         return 0;
 285
 286  fail_mmapsem:
 287         up_write(&mm->mmap_sem);
 288         return rc;
 289 }
 290
 291 const char *arch_vma_name(struct vm_area_struct *vma)
 292 {
 293         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 294                 return "[vdso]";
 295         return NULL;
 296 }
 297
 298
 299
 300 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 301                                   unsigned long *size)
 302 {
 303         Elf32_Shdr *sechdrs;
 304         unsigned int i;
 305         char *secnames;
 306
 307         /* Grab section headers and strings so we can tell who is who */
 308         sechdrs = (void *)ehdr + ehdr->e_shoff;
 309         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 310
 311         /* Find the section they want */
 312         for (i = 1; i < ehdr->e_shnum; i++) {
 313                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 314                         if (size)
 315                                 *size = sechdrs[i].sh_size;
 316                         return (void *)ehdr + sechdrs[i].sh_offset;
 317                 }
 318         }
 319         *size = 0;
 320         return NULL;
 321 }
 322
 323 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 324                                         const char *symname)
 325 {
 326         unsigned int i;
 327         char name[MAX_SYMNAME], *c;
 328
 329         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 330                 if (lib->dynsym[i].st_name == 0)
 331                         continue;
 332                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 333                         MAX_SYMNAME);
 334                 c = strchr(name, '@');
 335                 if (c)
 336                         *c = 0;
 337                 if (strcmp(symname, name) == 0)
 338                         return &lib->dynsym[i];
 339         }
 340         return NULL;
 341 }
 342
 343 /* Note that we assume the section is .text and the symbol is relative to
 344  * the library base
 345  */
 346 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 347                                             const char *symname)
 348 {
 349         Elf32_Sym *sym = find_symbol32(lib, symname);
 350
 351         if (sym == NULL) {
 352                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 353                        symname);
 354                 return 0;
 355         }
 356         return sym->st_value - VDSO32_LBASE;
 357 }
 358
 359 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 360                                        struct lib64_elfinfo *v64,
 361                                        const char *orig, const char *fix)
 362 {
 363         Elf32_Sym *sym32_gen, *sym32_fix;
 364
 365         sym32_gen = find_symbol32(v32, orig);
 366         if (sym32_gen == NULL) {
 367                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 368                 return -1;
 369         }
 370         if (fix == NULL) {
 371                 sym32_gen->st_name = 0;
 372                 return 0;
 373         }
 374         sym32_fix = find_symbol32(v32, fix);
 375         if (sym32_fix == NULL) {
 376                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 377                 return -1;
 378         }
 379         sym32_gen->st_value = sym32_fix->st_value;
 380         sym32_gen->st_size = sym32_fix->st_size;
 381         sym32_gen->st_info = sym32_fix->st_info;
 382         sym32_gen->st_other = sym32_fix->st_other;
 383         sym32_gen->st_shndx = sym32_fix->st_shndx;
 384
 385         return 0;
 386 }
 387
 388
 389 #ifdef CONFIG_PPC64
 390
 391 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 392                                   unsigned long *size)
 393 {
 394         Elf64_Shdr *sechdrs;
 395         unsigned int i;
 396         char *secnames;
 397
 398         /* Grab section headers and strings so we can tell who is who */
 399         sechdrs = (void *)ehdr + ehdr->e_shoff;
 400         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 401
 402         /* Find the section they want */
 403         for (i = 1; i < ehdr->e_shnum; i++) {
 404                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 405                         if (size)
 406                                 *size = sechdrs[i].sh_size;
 407                         return (void *)ehdr + sechdrs[i].sh_offset;
 408                 }
 409         }
 410         if (size)
 411                 *size = 0;
 412         return NULL;
 413 }
 414
 415 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 416                                         const char *symname)
 417 {
 418         unsigned int i;
 419         char name[MAX_SYMNAME], *c;
 420
 421         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 422                 if (lib->dynsym[i].st_name == 0)
 423                         continue;
 424                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 425                         MAX_SYMNAME);
 426                 c = strchr(name, '@');
 427                 if (c)
 428                         *c = 0;
 429                 if (strcmp(symname, name) == 0)
 430                         return &lib->dynsym[i];
 431         }
 432         return NULL;
 433 }
 434
 435 /* Note that we assume the section is .text and the symbol is relative to
 436  * the library base
 437  */
 438 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 439                                             const char *symname)
 440 {
 441         Elf64_Sym *sym = find_symbol64(lib, symname);
 442
 443         if (sym == NULL) {
 444                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 445                        symname);
 446                 return 0;
 447         }
 448 #ifdef VDS64_HAS_DESCRIPTORS
 449         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 450                 VDSO64_LBASE;
 451 #else
 452         return sym->st_value - VDSO64_LBASE;
 453 #endif
 454 }
 455
 456 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 457                                        struct lib64_elfinfo *v64,
 458                                        const char *orig, const char *fix)
 459 {
 460         Elf64_Sym *sym64_gen, *sym64_fix;
 461
 462         sym64_gen = find_symbol64(v64, orig);
 463         if (sym64_gen == NULL) {
 464                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 465                 return -1;
 466         }
 467         if (fix == NULL) {
 468                 sym64_gen->st_name = 0;
 469                 return 0;
 470         }
 471         sym64_fix = find_symbol64(v64, fix);
 472         if (sym64_fix == NULL) {
 473                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 474                 return -1;
 475         }
 476         sym64_gen->st_value = sym64_fix->st_value;
 477         sym64_gen->st_size = sym64_fix->st_size;
 478         sym64_gen->st_info = sym64_fix->st_info;
 479         sym64_gen->st_other = sym64_fix->st_other;
 480         sym64_gen->st_shndx = sym64_fix->st_shndx;
 481
 482         return 0;
 483 }
 484
 485 #endif /* CONFIG_PPC64 */
 486
 487
 488 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 489                                         struct lib64_elfinfo *v64)
 490 {
 491         void *sect;
 492
 493         /*
 494          * Locate symbol tables & text section
 495          */
 496
 497         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 498         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 499         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 500                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 501                 return -1;
 502         }
 503         sect = find_section32(v32->hdr, ".text", NULL);
 504         if (sect == NULL) {
 505                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 506                 return -1;
 507         }
 508         v32->text = sect - vdso32_kbase;
 509
 510 #ifdef CONFIG_PPC64
 511         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 512         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 513         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 514                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 515                 return -1;
 516         }
 517         sect = find_section64(v64->hdr, ".text", NULL);
 518         if (sect == NULL) {
 519                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 520                 return -1;
 521         }
 522         v64->text = sect - vdso64_kbase;
 523 #endif /* CONFIG_PPC64 */
 524
 525         return 0;
 526 }
 527
 528 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 529                                           struct lib64_elfinfo *v64)
 530 {
 531         /*
 532          * Find signal trampolines
 533          */
 534
 535 #ifdef CONFIG_PPC64
 536         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 537 #endif
 538         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 539         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 540 }
 541
 542 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 543                                        struct lib64_elfinfo *v64)
 544 {
 545         Elf32_Sym *sym32;
 546 #ifdef CONFIG_PPC64
 547         Elf64_Sym *sym64;
 548
 549         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 550         if (sym64 == NULL) {
 551                 printk(KERN_ERR "vDSO64: Can't find symbol "
 552                        "__kernel_datapage_offset !\n");
 553                 return -1;
 554         }
 555         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 556                 (vdso64_pages << PAGE_SHIFT) -
 557                 (sym64->st_value - VDSO64_LBASE);
 558 #endif /* CONFIG_PPC64 */
 559
 560         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 561         if (sym32 == NULL) {
 562                 printk(KERN_ERR "vDSO32: Can't find symbol "
 563                        "__kernel_datapage_offset !\n");
 564                 return -1;
 565         }
 566         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 567                 (vdso32_pages << PAGE_SHIFT) -
 568                 (sym32->st_value - VDSO32_LBASE);
 569
 570         return 0;
 571 }
 572
 573
 574 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 575                                       struct lib64_elfinfo *v64)
 576 {
 577         void *start32;
 578         unsigned long size32;
 579
 580 #ifdef CONFIG_PPC64
 581         void *start64;
 582         unsigned long size64;
 583
 584         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 585         if (start64)
 586                 do_feature_fixups(cur_cpu_spec->cpu_features,
 587                                   start64, start64 + size64);
 588
 589         start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
 590         if (start64)
 591                 do_feature_fixups(cur_cpu_spec->mmu_features,
 592                                   start64, start64 + size64);
 593
 594         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 595         if (start64)
 596                 do_feature_fixups(powerpc_firmware_features,
 597                                   start64, start64 + size64);
 598
 599         start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
 600         if (start64)
 601                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 602                                  start64, start64 + size64);
 603 #endif /* CONFIG_PPC64 */
 604
 605         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 606         if (start32)
 607                 do_feature_fixups(cur_cpu_spec->cpu_features,
 608                                   start32, start32 + size32);
 609
 610         start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
 611         if (start32)
 612                 do_feature_fixups(cur_cpu_spec->mmu_features,
 613                                   start32, start32 + size32);
 614
 615 #ifdef CONFIG_PPC64
 616         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 617         if (start32)
 618                 do_feature_fixups(powerpc_firmware_features,
 619                                   start32, start32 + size32);
 620 #endif /* CONFIG_PPC64 */
 621
 622         start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
 623         if (start32)
 624                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 625                                  start32, start32 + size32);
 626
 627         return 0;
 628 }
 629
 630 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 631                                        struct lib64_elfinfo *v64)
 632 {
 633         int i;
 634
 635         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 636                 struct vdso_patch_def *patch = &vdso_patches[i];
 637                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 638                         == patch->ftr_value;
 639                 if (!match)
 640                         continue;
 641
 642                 DBG("replacing %s with %s...\n", patch->gen_name,
 643                     patch->fix_name ? "NONE" : patch->fix_name);
 644
 645                 /*
 646                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 647                  * patch the "." symbol on 64 bits.
 648                  * It would be easy to do, but doesn't seem to be necessary,
 649                  * patching the OPD symbol is enough.
 650                  */
 651                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 652                                      patch->fix_name);
 653 #ifdef CONFIG_PPC64
 654                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 655                                      patch->fix_name);
 656 #endif /* CONFIG_PPC64 */
 657         }
 658
 659         return 0;
 660 }
 661
 662
 663 static __init int vdso_setup(void)
 664 {
 665         struct lib32_elfinfo    v32;
 666         struct lib64_elfinfo    v64;
 667
 668         v32.hdr = vdso32_kbase;
 669 #ifdef CONFIG_PPC64
 670         v64.hdr = vdso64_kbase;
 671 #endif
 672         if (vdso_do_find_sections(&v32, &v64))
 673                 return -1;
 674
 675         if (vdso_fixup_datapage(&v32, &v64))
 676                 return -1;
 677
 678         if (vdso_fixup_features(&v32, &v64))
 679                 return -1;
 680
 681         if (vdso_fixup_alt_funcs(&v32, &v64))
 682                 return -1;
 683
 684         vdso_setup_trampolines(&v32, &v64);
 685
 686         return 0;
 687 }
 688
 689 /*
 690  * Called from setup_arch to initialize the bitmap of available
 691  * syscalls in the systemcfg page
 692  */
 693 static void __init vdso_setup_syscall_map(void)
 694 {
 695         unsigned int i;
 696         extern unsigned long *sys_call_table;
 697         extern unsigned long sys_ni_syscall;
 698
 699
 700         for (i = 0; i < __NR_syscalls; i++) {
 701 #ifdef CONFIG_PPC64
 702                 if (sys_call_table[i*2] != sys_ni_syscall)
 703                         vdso_data->syscall_map_64[i >> 5] |=
 704                                 0x80000000UL >> (i & 0x1f);
 705                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 706                         vdso_data->syscall_map_32[i >> 5] |=
 707                                 0x80000000UL >> (i & 0x1f);
 708 #else /* CONFIG_PPC64 */
 709                 if (sys_call_table[i] != sys_ni_syscall)
 710                         vdso_data->syscall_map_32[i >> 5] |=
 711                                 0x80000000UL >> (i & 0x1f);
 712 #endif /* CONFIG_PPC64 */
 713         }
 714 }
 715
 716
 717 static int __init vdso_init(void)
 718 {
 719         int i;
 720
 721 #ifdef CONFIG_PPC64
 722         /*
 723          * Fill up the "systemcfg" stuff for backward compatibility
 724          */
 725         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 726         vdso_data->version.major = SYSTEMCFG_MAJOR;
 727         vdso_data->version.minor = SYSTEMCFG_MINOR;
 728         vdso_data->processor = mfspr(SPRN_PVR);
 729         /*
 730          * Fake the old platform number for pSeries and iSeries and add
 731          * in LPAR bit if necessary
 732          */
 733         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 734         if (firmware_has_feature(FW_FEATURE_LPAR))
 735                 vdso_data->platform |= 1;
 736         vdso_data->physicalMemorySize = memblock_phys_mem_size();
 737         vdso_data->dcache_size = ppc64_caches.dsize;
 738         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 739         vdso_data->icache_size = ppc64_caches.isize;
 740         vdso_data->icache_line_size = ppc64_caches.iline_size;
 741
 742         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
 743         vdso_data->dcache_block_size = ppc64_caches.dline_size;
 744         vdso_data->icache_block_size = ppc64_caches.iline_size;
 745         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
 746         vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
 747
 748         /*
 749          * Calculate the size of the 64 bits vDSO
 750          */
 751         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 752         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 753 #else
 754         vdso_data->dcache_block_size = L1_CACHE_BYTES;
 755         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
 756         vdso_data->icache_block_size = L1_CACHE_BYTES;
 757         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
 758 #endif /* CONFIG_PPC64 */
 759
 760
 761         /*
 762          * Calculate the size of the 32 bits vDSO
 763          */
 764         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 765         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 766
 767
 768         /*
 769          * Setup the syscall map in the vDOS
 770          */
 771         vdso_setup_syscall_map();
 772
 773         /*
 774          * Initialize the vDSO images in memory, that is do necessary
 775          * fixups of vDSO symbols, locate trampolines, etc...
 776          */
 777         if (vdso_setup()) {
 778                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 779                 vdso32_pages = 0;
 780 #ifdef CONFIG_PPC64
 781                 vdso64_pages = 0;
 782 #endif
 783                 return 0;
 784         }
 785
 786         /* Make sure pages are in the correct state */
 787         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 788                                   GFP_KERNEL);
 789         BUG_ON(vdso32_pagelist == NULL);
 790         for (i = 0; i < vdso32_pages; i++) {
 791                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 792                 ClearPageReserved(pg);
 793                 get_page(pg);
 794                 vdso32_pagelist[i] = pg;
 795         }
 796         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 797         vdso32_pagelist[i] = NULL;
 798
 799 #ifdef CONFIG_PPC64
 800         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 801                                   GFP_KERNEL);
 802         BUG_ON(vdso64_pagelist == NULL);
 803         for (i = 0; i < vdso64_pages; i++) {
 804                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 805                 ClearPageReserved(pg);
 806                 get_page(pg);
 807                 vdso64_pagelist[i] = pg;
 808         }
 809         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 810         vdso64_pagelist[i] = NULL;
 811 #endif /* CONFIG_PPC64 */
 812
 813         get_page(virt_to_page(vdso_data));
 814
 815         smp_wmb();
 816         vdso_ready = 1;
 817
 818         return 0;
 819 }
 820 arch_initcall(vdso_init);
 821
 822 int in_gate_area_no_mm(unsigned long addr)
 823 {
 824         return 0;
 825 }
 826
 827 int in_gate_area(struct mm_struct *mm, unsigned long addr)
 828 {
 829         return 0;
 830 }
 831
 832 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
 833 {
 834         return NULL;
 835 }
 836