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