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/module.h>
  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/lmb.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 extern char vdso32_start, vdso32_end;
  53 static void *vdso32_kbase = &vdso32_start;
  54 static unsigned int vdso32_pages;
  55 static struct page **vdso32_pagelist;
  56 unsigned long vdso32_sigtramp;
  57 unsigned long vdso32_rt_sigtramp;
  58
  59 #ifdef CONFIG_PPC64
  60 extern char vdso64_start, vdso64_end;
  61 static void *vdso64_kbase = &vdso64_start;
  62 static unsigned int vdso64_pages;
  63 static struct page **vdso64_pagelist;
  64 unsigned long vdso64_rt_sigtramp;
  65 #endif /* CONFIG_PPC64 */
  66
  67 static int vdso_ready;
  68
  69 /*
  70  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  71  * Once the early boot kernel code no longer needs to muck around
  72  * with it, it will become dynamically allocated
  73  */
  74 static union {
  75         struct vdso_data        data;
  76         u8                      page[PAGE_SIZE];
  77 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  78 struct vdso_data *vdso_data = &vdso_data_store.data;
  79
  80 /* Format of the patch table */
  81 struct vdso_patch_def
  82 {
  83         unsigned long   ftr_mask, ftr_value;
  84         const char      *gen_name;
  85         const char      *fix_name;
  86 };
  87
  88 /* Table of functions to patch based on the CPU type/revision
  89  *
  90  * Currently, we only change sync_dicache to do nothing on processors
  91  * with a coherent icache
  92  */
  93 static struct vdso_patch_def vdso_patches[] = {
  94         {
  95                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  96                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  97         },
  98         {
  99                 CPU_FTR_USE_TB, 0,
 100                 "__kernel_gettimeofday", NULL
 101         },
 102         {
 103                 CPU_FTR_USE_TB, 0,
 104                 "__kernel_clock_gettime", NULL
 105         },
 106         {
 107                 CPU_FTR_USE_TB, 0,
 108                 "__kernel_clock_getres", NULL
 109         },
 110         {
 111                 CPU_FTR_USE_TB, 0,
 112                 "__kernel_get_tbfreq", NULL
 113         },
 114 };
 115
 116 /*
 117  * Some infos carried around for each of them during parsing at
 118  * boot time.
 119  */
 120 struct lib32_elfinfo
 121 {
 122         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 123         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 124         unsigned long   dynsymsize;     /* size of .dynsym section */
 125         char            *dynstr;        /* ptr to .dynstr section */
 126         unsigned long   text;           /* offset of .text section in .so */
 127 };
 128
 129 struct lib64_elfinfo
 130 {
 131         Elf64_Ehdr      *hdr;
 132         Elf64_Sym       *dynsym;
 133         unsigned long   dynsymsize;
 134         char            *dynstr;
 135         unsigned long   text;
 136 };
 137
 138
 139 #ifdef __DEBUG
 140 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 141 {
 142         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 143                page_count(pg),
 144                pg->flags);
 145         if (upg && !IS_ERR(upg) /* && pg != upg*/) {
 146                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 147                                                        << PAGE_SHIFT),
 148                        page_count(upg),
 149                        upg->flags);
 150         }
 151         printk("\n");
 152 }
 153
 154 static void dump_vdso_pages(struct vm_area_struct * vma)
 155 {
 156         int i;
 157
 158         if (!vma || test_thread_flag(TIF_32BIT)) {
 159                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 160                 for (i=0; i<vdso32_pages; i++) {
 161                         struct page *pg = virt_to_page(vdso32_kbase +
 162                                                        i*PAGE_SIZE);
 163                         struct page *upg = (vma && vma->vm_mm) ?
 164                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 165                                 : NULL;
 166                         dump_one_vdso_page(pg, upg);
 167                 }
 168         }
 169         if (!vma || !test_thread_flag(TIF_32BIT)) {
 170                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 171                 for (i=0; i<vdso64_pages; i++) {
 172                         struct page *pg = virt_to_page(vdso64_kbase +
 173                                                        i*PAGE_SIZE);
 174                         struct page *upg = (vma && vma->vm_mm) ?
 175                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 176                                 : NULL;
 177                         dump_one_vdso_page(pg, upg);
 178                 }
 179         }
 180 }
 181 #endif /* DEBUG */
 182
 183 /*
 184  * This is called from binfmt_elf, we create the special vma for the
 185  * vDSO and insert it into the mm struct tree
 186  */
 187 int arch_setup_additional_pages(struct linux_binprm *bprm,
 188                                 int executable_stack)
 189 {
 190         struct mm_struct *mm = current->mm;
 191         struct page **vdso_pagelist;
 192         unsigned long vdso_pages;
 193         unsigned long vdso_base;
 194         int rc;
 195
 196         if (!vdso_ready)
 197                 return 0;
 198
 199 #ifdef CONFIG_PPC64
 200         if (test_thread_flag(TIF_32BIT)) {
 201                 vdso_pagelist = vdso32_pagelist;
 202                 vdso_pages = vdso32_pages;
 203                 vdso_base = VDSO32_MBASE;
 204         } else {
 205                 vdso_pagelist = vdso64_pagelist;
 206                 vdso_pages = vdso64_pages;
 207                 vdso_base = VDSO64_MBASE;
 208         }
 209 #else
 210         vdso_pagelist = vdso32_pagelist;
 211         vdso_pages = vdso32_pages;
 212         vdso_base = VDSO32_MBASE;
 213 #endif
 214
 215         current->mm->context.vdso_base = 0;
 216
 217         /* vDSO has a problem and was disabled, just don't "enable" it for the
 218          * process
 219          */
 220         if (vdso_pages == 0)
 221                 return 0;
 222         /* Add a page to the vdso size for the data page */
 223         vdso_pages ++;
 224
 225         /*
 226          * pick a base address for the vDSO in process space. We try to put it
 227          * at vdso_base which is the "natural" base for it, but we might fail
 228          * and end up putting it elsewhere.
 229          */
 230         down_write(&mm->mmap_sem);
 231         vdso_base = get_unmapped_area(NULL, vdso_base,
 232                                       vdso_pages << PAGE_SHIFT, 0, 0);
 233         if (IS_ERR_VALUE(vdso_base)) {
 234                 rc = vdso_base;
 235                 goto fail_mmapsem;
 236         }
 237
 238         /*
 239          * our vma flags don't have VM_WRITE so by default, the process isn't
 240          * allowed to write those pages.
 241          * gdb can break that with ptrace interface, and thus trigger COW on
 242          * those pages but it's then your responsibility to never do that on
 243          * the "data" page of the vDSO or you'll stop getting kernel updates
 244          * and your nice userland gettimeofday will be totally dead.
 245          * It's fine to use that for setting breakpoints in the vDSO code
 246          * pages though
 247          *
 248          * Make sure the vDSO gets into every core dump.
 249          * Dumping its contents makes post-mortem fully interpretable later
 250          * without matching up the same kernel and hardware config to see
 251          * what PC values meant.
 252          */
 253         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 254                                      VM_READ|VM_EXEC|
 255                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
 256                                      VM_ALWAYSDUMP,
 257                                      vdso_pagelist);
 258         if (rc)
 259                 goto fail_mmapsem;
 260
 261         /* Put vDSO base into mm struct */
 262         current->mm->context.vdso_base = vdso_base;
 263
 264         up_write(&mm->mmap_sem);
 265         return 0;
 266
 267  fail_mmapsem:
 268         up_write(&mm->mmap_sem);
 269         return rc;
 270 }
 271
 272 const char *arch_vma_name(struct vm_area_struct *vma)
 273 {
 274         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 275                 return "[vdso]";
 276         return NULL;
 277 }
 278
 279
 280
 281 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 282                                   unsigned long *size)
 283 {
 284         Elf32_Shdr *sechdrs;
 285         unsigned int i;
 286         char *secnames;
 287
 288         /* Grab section headers and strings so we can tell who is who */
 289         sechdrs = (void *)ehdr + ehdr->e_shoff;
 290         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 291
 292         /* Find the section they want */
 293         for (i = 1; i < ehdr->e_shnum; i++) {
 294                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 295                         if (size)
 296                                 *size = sechdrs[i].sh_size;
 297                         return (void *)ehdr + sechdrs[i].sh_offset;
 298                 }
 299         }
 300         *size = 0;
 301         return NULL;
 302 }
 303
 304 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 305                                         const char *symname)
 306 {
 307         unsigned int i;
 308         char name[MAX_SYMNAME], *c;
 309
 310         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 311                 if (lib->dynsym[i].st_name == 0)
 312                         continue;
 313                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 314                         MAX_SYMNAME);
 315                 c = strchr(name, '@');
 316                 if (c)
 317                         *c = 0;
 318                 if (strcmp(symname, name) == 0)
 319                         return &lib->dynsym[i];
 320         }
 321         return NULL;
 322 }
 323
 324 /* Note that we assume the section is .text and the symbol is relative to
 325  * the library base
 326  */
 327 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 328                                             const char *symname)
 329 {
 330         Elf32_Sym *sym = find_symbol32(lib, symname);
 331
 332         if (sym == NULL) {
 333                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 334                        symname);
 335                 return 0;
 336         }
 337         return sym->st_value - VDSO32_LBASE;
 338 }
 339
 340 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 341                                        struct lib64_elfinfo *v64,
 342                                        const char *orig, const char *fix)
 343 {
 344         Elf32_Sym *sym32_gen, *sym32_fix;
 345
 346         sym32_gen = find_symbol32(v32, orig);
 347         if (sym32_gen == NULL) {
 348                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 349                 return -1;
 350         }
 351         if (fix == NULL) {
 352                 sym32_gen->st_name = 0;
 353                 return 0;
 354         }
 355         sym32_fix = find_symbol32(v32, fix);
 356         if (sym32_fix == NULL) {
 357                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 358                 return -1;
 359         }
 360         sym32_gen->st_value = sym32_fix->st_value;
 361         sym32_gen->st_size = sym32_fix->st_size;
 362         sym32_gen->st_info = sym32_fix->st_info;
 363         sym32_gen->st_other = sym32_fix->st_other;
 364         sym32_gen->st_shndx = sym32_fix->st_shndx;
 365
 366         return 0;
 367 }
 368
 369
 370 #ifdef CONFIG_PPC64
 371
 372 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 373                                   unsigned long *size)
 374 {
 375         Elf64_Shdr *sechdrs;
 376         unsigned int i;
 377         char *secnames;
 378
 379         /* Grab section headers and strings so we can tell who is who */
 380         sechdrs = (void *)ehdr + ehdr->e_shoff;
 381         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 382
 383         /* Find the section they want */
 384         for (i = 1; i < ehdr->e_shnum; i++) {
 385                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 386                         if (size)
 387                                 *size = sechdrs[i].sh_size;
 388                         return (void *)ehdr + sechdrs[i].sh_offset;
 389                 }
 390         }
 391         if (size)
 392                 *size = 0;
 393         return NULL;
 394 }
 395
 396 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 397                                         const char *symname)
 398 {
 399         unsigned int i;
 400         char name[MAX_SYMNAME], *c;
 401
 402         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 403                 if (lib->dynsym[i].st_name == 0)
 404                         continue;
 405                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 406                         MAX_SYMNAME);
 407                 c = strchr(name, '@');
 408                 if (c)
 409                         *c = 0;
 410                 if (strcmp(symname, name) == 0)
 411                         return &lib->dynsym[i];
 412         }
 413         return NULL;
 414 }
 415
 416 /* Note that we assume the section is .text and the symbol is relative to
 417  * the library base
 418  */
 419 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 420                                             const char *symname)
 421 {
 422         Elf64_Sym *sym = find_symbol64(lib, symname);
 423
 424         if (sym == NULL) {
 425                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 426                        symname);
 427                 return 0;
 428         }
 429 #ifdef VDS64_HAS_DESCRIPTORS
 430         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 431                 VDSO64_LBASE;
 432 #else
 433         return sym->st_value - VDSO64_LBASE;
 434 #endif
 435 }
 436
 437 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 438                                        struct lib64_elfinfo *v64,
 439                                        const char *orig, const char *fix)
 440 {
 441         Elf64_Sym *sym64_gen, *sym64_fix;
 442
 443         sym64_gen = find_symbol64(v64, orig);
 444         if (sym64_gen == NULL) {
 445                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 446                 return -1;
 447         }
 448         if (fix == NULL) {
 449                 sym64_gen->st_name = 0;
 450                 return 0;
 451         }
 452         sym64_fix = find_symbol64(v64, fix);
 453         if (sym64_fix == NULL) {
 454                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 455                 return -1;
 456         }
 457         sym64_gen->st_value = sym64_fix->st_value;
 458         sym64_gen->st_size = sym64_fix->st_size;
 459         sym64_gen->st_info = sym64_fix->st_info;
 460         sym64_gen->st_other = sym64_fix->st_other;
 461         sym64_gen->st_shndx = sym64_fix->st_shndx;
 462
 463         return 0;
 464 }
 465
 466 #endif /* CONFIG_PPC64 */
 467
 468
 469 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 470                                         struct lib64_elfinfo *v64)
 471 {
 472         void *sect;
 473
 474         /*
 475          * Locate symbol tables & text section
 476          */
 477
 478         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 479         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 480         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 481                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 482                 return -1;
 483         }
 484         sect = find_section32(v32->hdr, ".text", NULL);
 485         if (sect == NULL) {
 486                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 487                 return -1;
 488         }
 489         v32->text = sect - vdso32_kbase;
 490
 491 #ifdef CONFIG_PPC64
 492         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 493         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 494         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 495                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 496                 return -1;
 497         }
 498         sect = find_section64(v64->hdr, ".text", NULL);
 499         if (sect == NULL) {
 500                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 501                 return -1;
 502         }
 503         v64->text = sect - vdso64_kbase;
 504 #endif /* CONFIG_PPC64 */
 505
 506         return 0;
 507 }
 508
 509 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 510                                           struct lib64_elfinfo *v64)
 511 {
 512         /*
 513          * Find signal trampolines
 514          */
 515
 516 #ifdef CONFIG_PPC64
 517         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 518 #endif
 519         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 520         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 521 }
 522
 523 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 524                                        struct lib64_elfinfo *v64)
 525 {
 526         Elf32_Sym *sym32;
 527 #ifdef CONFIG_PPC64
 528         Elf64_Sym *sym64;
 529
 530         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 531         if (sym64 == NULL) {
 532                 printk(KERN_ERR "vDSO64: Can't find symbol "
 533                        "__kernel_datapage_offset !\n");
 534                 return -1;
 535         }
 536         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 537                 (vdso64_pages << PAGE_SHIFT) -
 538                 (sym64->st_value - VDSO64_LBASE);
 539 #endif /* CONFIG_PPC64 */
 540
 541         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 542         if (sym32 == NULL) {
 543                 printk(KERN_ERR "vDSO32: Can't find symbol "
 544                        "__kernel_datapage_offset !\n");
 545                 return -1;
 546         }
 547         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 548                 (vdso32_pages << PAGE_SHIFT) -
 549                 (sym32->st_value - VDSO32_LBASE);
 550
 551         return 0;
 552 }
 553
 554
 555 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 556                                       struct lib64_elfinfo *v64)
 557 {
 558         void *start32;
 559         unsigned long size32;
 560
 561 #ifdef CONFIG_PPC64
 562         void *start64;
 563         unsigned long size64;
 564
 565         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 566         if (start64)
 567                 do_feature_fixups(cur_cpu_spec->cpu_features,
 568                                   start64, start64 + size64);
 569
 570         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 571         if (start64)
 572                 do_feature_fixups(powerpc_firmware_features,
 573                                   start64, start64 + size64);
 574 #endif /* CONFIG_PPC64 */
 575
 576         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 577         if (start32)
 578                 do_feature_fixups(cur_cpu_spec->cpu_features,
 579                                   start32, start32 + size32);
 580
 581 #ifdef CONFIG_PPC64
 582         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 583         if (start32)
 584                 do_feature_fixups(powerpc_firmware_features,
 585                                   start32, start32 + size32);
 586 #endif /* CONFIG_PPC64 */
 587
 588         return 0;
 589 }
 590
 591 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 592                                        struct lib64_elfinfo *v64)
 593 {
 594         int i;
 595
 596         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 597                 struct vdso_patch_def *patch = &vdso_patches[i];
 598                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 599                         == patch->ftr_value;
 600                 if (!match)
 601                         continue;
 602
 603                 DBG("replacing %s with %s...\n", patch->gen_name,
 604                     patch->fix_name ? "NONE" : patch->fix_name);
 605
 606                 /*
 607                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 608                  * patch the "." symbol on 64 bits.
 609                  * It would be easy to do, but doesn't seem to be necessary,
 610                  * patching the OPD symbol is enough.
 611                  */
 612                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 613                                      patch->fix_name);
 614 #ifdef CONFIG_PPC64
 615                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 616                                      patch->fix_name);
 617 #endif /* CONFIG_PPC64 */
 618         }
 619
 620         return 0;
 621 }
 622
 623
 624 static __init int vdso_setup(void)
 625 {
 626         struct lib32_elfinfo    v32;
 627         struct lib64_elfinfo    v64;
 628
 629         v32.hdr = vdso32_kbase;
 630 #ifdef CONFIG_PPC64
 631         v64.hdr = vdso64_kbase;
 632 #endif
 633         if (vdso_do_find_sections(&v32, &v64))
 634                 return -1;
 635
 636         if (vdso_fixup_datapage(&v32, &v64))
 637                 return -1;
 638
 639         if (vdso_fixup_features(&v32, &v64))
 640                 return -1;
 641
 642         if (vdso_fixup_alt_funcs(&v32, &v64))
 643                 return -1;
 644
 645         vdso_setup_trampolines(&v32, &v64);
 646
 647         return 0;
 648 }
 649
 650 /*
 651  * Called from setup_arch to initialize the bitmap of available
 652  * syscalls in the systemcfg page
 653  */
 654 static void __init vdso_setup_syscall_map(void)
 655 {
 656         unsigned int i;
 657         extern unsigned long *sys_call_table;
 658         extern unsigned long sys_ni_syscall;
 659
 660
 661         for (i = 0; i < __NR_syscalls; i++) {
 662 #ifdef CONFIG_PPC64
 663                 if (sys_call_table[i*2] != sys_ni_syscall)
 664                         vdso_data->syscall_map_64[i >> 5] |=
 665                                 0x80000000UL >> (i & 0x1f);
 666                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 667                         vdso_data->syscall_map_32[i >> 5] |=
 668                                 0x80000000UL >> (i & 0x1f);
 669 #else /* CONFIG_PPC64 */
 670                 if (sys_call_table[i] != sys_ni_syscall)
 671                         vdso_data->syscall_map_32[i >> 5] |=
 672                                 0x80000000UL >> (i & 0x1f);
 673 #endif /* CONFIG_PPC64 */
 674         }
 675 }
 676
 677
 678 static int __init vdso_init(void)
 679 {
 680         int i;
 681
 682 #ifdef CONFIG_PPC64
 683         /*
 684          * Fill up the "systemcfg" stuff for backward compatiblity
 685          */
 686         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 687         vdso_data->version.major = SYSTEMCFG_MAJOR;
 688         vdso_data->version.minor = SYSTEMCFG_MINOR;
 689         vdso_data->processor = mfspr(SPRN_PVR);
 690         /*
 691          * Fake the old platform number for pSeries and iSeries and add
 692          * in LPAR bit if necessary
 693          */
 694         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 695         if (firmware_has_feature(FW_FEATURE_LPAR))
 696                 vdso_data->platform |= 1;
 697         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 698         vdso_data->dcache_size = ppc64_caches.dsize;
 699         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 700         vdso_data->icache_size = ppc64_caches.isize;
 701         vdso_data->icache_line_size = ppc64_caches.iline_size;
 702
 703         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
 704         vdso_data->dcache_block_size = ppc64_caches.dline_size;
 705         vdso_data->icache_block_size = ppc64_caches.iline_size;
 706         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
 707         vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
 708
 709         /*
 710          * Calculate the size of the 64 bits vDSO
 711          */
 712         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 713         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 714 #else
 715         vdso_data->dcache_block_size = L1_CACHE_BYTES;
 716         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
 717         vdso_data->icache_block_size = L1_CACHE_BYTES;
 718         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
 719 #endif /* CONFIG_PPC64 */
 720
 721
 722         /*
 723          * Calculate the size of the 32 bits vDSO
 724          */
 725         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 726         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 727
 728
 729         /*
 730          * Setup the syscall map in the vDOS
 731          */
 732         vdso_setup_syscall_map();
 733
 734         /*
 735          * Initialize the vDSO images in memory, that is do necessary
 736          * fixups of vDSO symbols, locate trampolines, etc...
 737          */
 738         if (vdso_setup()) {
 739                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 740                 vdso32_pages = 0;
 741 #ifdef CONFIG_PPC64
 742                 vdso64_pages = 0;
 743 #endif
 744                 return 0;
 745         }
 746
 747         /* Make sure pages are in the correct state */
 748         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 749                                   GFP_KERNEL);
 750         BUG_ON(vdso32_pagelist == NULL);
 751         for (i = 0; i < vdso32_pages; i++) {
 752                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 753                 ClearPageReserved(pg);
 754                 get_page(pg);
 755                 vdso32_pagelist[i] = pg;
 756         }
 757         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 758         vdso32_pagelist[i] = NULL;
 759
 760 #ifdef CONFIG_PPC64
 761         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 762                                   GFP_KERNEL);
 763         BUG_ON(vdso64_pagelist == NULL);
 764         for (i = 0; i < vdso64_pages; i++) {
 765                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 766                 ClearPageReserved(pg);
 767                 get_page(pg);
 768                 vdso64_pagelist[i] = pg;
 769         }
 770         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 771         vdso64_pagelist[i] = NULL;
 772 #endif /* CONFIG_PPC64 */
 773
 774         get_page(virt_to_page(vdso_data));
 775
 776         smp_wmb();
 777         vdso_ready = 1;
 778
 779         return 0;
 780 }
 781 #ifdef CONFIG_PPC_MERGE
 782 arch_initcall(vdso_init);
 783 #endif
 784
 785 int in_gate_area_no_task(unsigned long addr)
 786 {
 787         return 0;
 788 }
 789
 790 int in_gate_area(struct task_struct *task, unsigned long addr)
 791 {
 792         return 0;
 793 }
 794
 795 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 796 {
 797         return NULL;
 798 }
 799