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