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/smp_lock.h>
  18 #include <linux/stddef.h>
  19 #include <linux/unistd.h>
  20 #include <linux/slab.h>
  21 #include <linux/user.h>
  22 #include <linux/elf.h>
  23 #include <linux/security.h>
  24 #include <linux/bootmem.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/lmb.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 unsigned int vdso32_pages;
  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 unsigned int vdso64_pages;
  62 unsigned long vdso64_rt_sigtramp;
  63 #endif /* CONFIG_PPC64 */
  64
  65 /*
  66  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  67  * Once the early boot kernel code no longer needs to muck around
  68  * with it, it will become dynamically allocated
  69  */
  70 static union {
  71         struct vdso_data        data;
  72         u8                      page[PAGE_SIZE];
  73 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  74 struct vdso_data *vdso_data = &vdso_data_store.data;
  75
  76 /* Format of the patch table */
  77 struct vdso_patch_def
  78 {
  79         unsigned long   ftr_mask, ftr_value;
  80         const char      *gen_name;
  81         const char      *fix_name;
  82 };
  83
  84 /* Table of functions to patch based on the CPU type/revision
  85  *
  86  * Currently, we only change sync_dicache to do nothing on processors
  87  * with a coherent icache
  88  */
  89 static struct vdso_patch_def vdso_patches[] = {
  90         {
  91                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  92                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  93         },
  94         {
  95                 CPU_FTR_USE_TB, 0,
  96                 "__kernel_gettimeofday", NULL
  97         },
  98 };
  99
 100 /*
 101  * Some infos carried around for each of them during parsing at
 102  * boot time.
 103  */
 104 struct lib32_elfinfo
 105 {
 106         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 107         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 108         unsigned long   dynsymsize;     /* size of .dynsym section */
 109         char            *dynstr;        /* ptr to .dynstr section */
 110         unsigned long   text;           /* offset of .text section in .so */
 111 };
 112
 113 struct lib64_elfinfo
 114 {
 115         Elf64_Ehdr      *hdr;
 116         Elf64_Sym       *dynsym;
 117         unsigned long   dynsymsize;
 118         char            *dynstr;
 119         unsigned long   text;
 120 };
 121
 122
 123 #ifdef __DEBUG
 124 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 125 {
 126         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 127                page_count(pg),
 128                pg->flags);
 129         if (upg/* && pg != upg*/) {
 130                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 131                                                        << PAGE_SHIFT),
 132                        page_count(upg),
 133                        upg->flags);
 134         }
 135         printk("\n");
 136 }
 137
 138 static void dump_vdso_pages(struct vm_area_struct * vma)
 139 {
 140         int i;
 141
 142         if (!vma || test_thread_flag(TIF_32BIT)) {
 143                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 144                 for (i=0; i<vdso32_pages; i++) {
 145                         struct page *pg = virt_to_page(vdso32_kbase +
 146                                                        i*PAGE_SIZE);
 147                         struct page *upg = (vma && vma->vm_mm) ?
 148                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 149                                 : NULL;
 150                         dump_one_vdso_page(pg, upg);
 151                 }
 152         }
 153         if (!vma || !test_thread_flag(TIF_32BIT)) {
 154                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 155                 for (i=0; i<vdso64_pages; i++) {
 156                         struct page *pg = virt_to_page(vdso64_kbase +
 157                                                        i*PAGE_SIZE);
 158                         struct page *upg = (vma && vma->vm_mm) ?
 159                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 160                                 : NULL;
 161                         dump_one_vdso_page(pg, upg);
 162                 }
 163         }
 164 }
 165 #endif /* DEBUG */
 166
 167 /*
 168  * Keep a dummy vma_close for now, it will prevent VMA merging.
 169  */
 170 static void vdso_vma_close(struct vm_area_struct * vma)
 171 {
 172 }
 173
 174 /*
 175  * Our nopage() function, maps in the actual vDSO kernel pages, they will
 176  * be mapped read-only by do_no_page(), and eventually COW'ed, either
 177  * right away for an initial write access, or by do_wp_page().
 178  */
 179 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 180                                      unsigned long address, int *type)
 181 {
 182         unsigned long offset = address - vma->vm_start;
 183         struct page *pg;
 184 #ifdef CONFIG_PPC64
 185         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
 186                 vdso64_kbase : vdso32_kbase;
 187 #else
 188         void *vbase = vdso32_kbase;
 189 #endif
 190
 191         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
 192             current->comm, address, offset);
 193
 194         if (address < vma->vm_start || address > vma->vm_end)
 195                 return NOPAGE_SIGBUS;
 196
 197         /*
 198          * Last page is systemcfg.
 199          */
 200         if ((vma->vm_end - address) <= PAGE_SIZE)
 201                 pg = virt_to_page(vdso_data);
 202         else
 203                 pg = virt_to_page(vbase + offset);
 204
 205         get_page(pg);
 206         DBG(" ->page count: %d\n", page_count(pg));
 207
 208         return pg;
 209 }
 210
 211 static struct vm_operations_struct vdso_vmops = {
 212         .close  = vdso_vma_close,
 213         .nopage = vdso_vma_nopage,
 214 };
 215
 216 /*
 217  * This is called from binfmt_elf, we create the special vma for the
 218  * vDSO and insert it into the mm struct tree
 219  */
 220 int arch_setup_additional_pages(struct linux_binprm *bprm,
 221                                 int executable_stack)
 222 {
 223         struct mm_struct *mm = current->mm;
 224         struct vm_area_struct *vma;
 225         unsigned long vdso_pages;
 226         unsigned long vdso_base;
 227         int rc;
 228
 229 #ifdef CONFIG_PPC64
 230         if (test_thread_flag(TIF_32BIT)) {
 231                 vdso_pages = vdso32_pages;
 232                 vdso_base = VDSO32_MBASE;
 233         } else {
 234                 vdso_pages = vdso64_pages;
 235                 vdso_base = VDSO64_MBASE;
 236         }
 237 #else
 238         vdso_pages = vdso32_pages;
 239         vdso_base = VDSO32_MBASE;
 240 #endif
 241
 242         current->mm->context.vdso_base = 0;
 243
 244         /* vDSO has a problem and was disabled, just don't "enable" it for the
 245          * process
 246          */
 247         if (vdso_pages == 0)
 248                 return 0;
 249         /* Add a page to the vdso size for the data page */
 250         vdso_pages ++;
 251
 252         /*
 253          * pick a base address for the vDSO in process space. We try to put it
 254          * at vdso_base which is the "natural" base for it, but we might fail
 255          * and end up putting it elsewhere.
 256          */
 257         down_write(&mm->mmap_sem);
 258         vdso_base = get_unmapped_area(NULL, vdso_base,
 259                                       vdso_pages << PAGE_SHIFT, 0, 0);
 260         if (IS_ERR_VALUE(vdso_base)) {
 261                 rc = vdso_base;
 262                 goto fail_mmapsem;
 263         }
 264
 265
 266         /* Allocate a VMA structure and fill it up */
 267         vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 268         if (vma == NULL) {
 269                 rc = -ENOMEM;
 270                 goto fail_mmapsem;
 271         }
 272         vma->vm_mm = mm;
 273         vma->vm_start = vdso_base;
 274         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 275
 276         /*
 277          * our vma flags don't have VM_WRITE so by default, the process isn't
 278          * allowed to write those pages.
 279          * gdb can break that with ptrace interface, and thus trigger COW on
 280          * those pages but it's then your responsibility to never do that on
 281          * the "data" page of the vDSO or you'll stop getting kernel updates
 282          * and your nice userland gettimeofday will be totally dead.
 283          * It's fine to use that for setting breakpoints in the vDSO code
 284          * pages though
 285          */
 286         vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
 287         vma->vm_flags |= mm->def_flags;
 288         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 289         vma->vm_ops = &vdso_vmops;
 290
 291         /* Insert new VMA */
 292         rc = insert_vm_struct(mm, vma);
 293         if (rc)
 294                 goto fail_vma;
 295
 296         /* Put vDSO base into mm struct and account for memory usage */
 297         current->mm->context.vdso_base = vdso_base;
 298         mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 299         up_write(&mm->mmap_sem);
 300         return 0;
 301
 302  fail_vma:
 303         kmem_cache_free(vm_area_cachep, vma);
 304  fail_mmapsem:
 305         up_write(&mm->mmap_sem);
 306         return rc;
 307 }
 308
 309 const char *arch_vma_name(struct vm_area_struct *vma)
 310 {
 311         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 312                 return "[vdso]";
 313         return NULL;
 314 }
 315
 316
 317
 318 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 319                                   unsigned long *size)
 320 {
 321         Elf32_Shdr *sechdrs;
 322         unsigned int i;
 323         char *secnames;
 324
 325         /* Grab section headers and strings so we can tell who is who */
 326         sechdrs = (void *)ehdr + ehdr->e_shoff;
 327         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 328
 329         /* Find the section they want */
 330         for (i = 1; i < ehdr->e_shnum; i++) {
 331                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 332                         if (size)
 333                                 *size = sechdrs[i].sh_size;
 334                         return (void *)ehdr + sechdrs[i].sh_offset;
 335                 }
 336         }
 337         *size = 0;
 338         return NULL;
 339 }
 340
 341 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 342                                         const char *symname)
 343 {
 344         unsigned int i;
 345         char name[MAX_SYMNAME], *c;
 346
 347         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 348                 if (lib->dynsym[i].st_name == 0)
 349                         continue;
 350                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 351                         MAX_SYMNAME);
 352                 c = strchr(name, '@');
 353                 if (c)
 354                         *c = 0;
 355                 if (strcmp(symname, name) == 0)
 356                         return &lib->dynsym[i];
 357         }
 358         return NULL;
 359 }
 360
 361 /* Note that we assume the section is .text and the symbol is relative to
 362  * the library base
 363  */
 364 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 365                                             const char *symname)
 366 {
 367         Elf32_Sym *sym = find_symbol32(lib, symname);
 368
 369         if (sym == NULL) {
 370                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 371                        symname);
 372                 return 0;
 373         }
 374         return sym->st_value - VDSO32_LBASE;
 375 }
 376
 377 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 378                                 struct lib64_elfinfo *v64,
 379                                 const char *orig, const char *fix)
 380 {
 381         Elf32_Sym *sym32_gen, *sym32_fix;
 382
 383         sym32_gen = find_symbol32(v32, orig);
 384         if (sym32_gen == NULL) {
 385                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 386                 return -1;
 387         }
 388         if (fix == NULL) {
 389                 sym32_gen->st_name = 0;
 390                 return 0;
 391         }
 392         sym32_fix = find_symbol32(v32, fix);
 393         if (sym32_fix == NULL) {
 394                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 395                 return -1;
 396         }
 397         sym32_gen->st_value = sym32_fix->st_value;
 398         sym32_gen->st_size = sym32_fix->st_size;
 399         sym32_gen->st_info = sym32_fix->st_info;
 400         sym32_gen->st_other = sym32_fix->st_other;
 401         sym32_gen->st_shndx = sym32_fix->st_shndx;
 402
 403         return 0;
 404 }
 405
 406
 407 #ifdef CONFIG_PPC64
 408
 409 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 410                                   unsigned long *size)
 411 {
 412         Elf64_Shdr *sechdrs;
 413         unsigned int i;
 414         char *secnames;
 415
 416         /* Grab section headers and strings so we can tell who is who */
 417         sechdrs = (void *)ehdr + ehdr->e_shoff;
 418         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 419
 420         /* Find the section they want */
 421         for (i = 1; i < ehdr->e_shnum; i++) {
 422                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 423                         if (size)
 424                                 *size = sechdrs[i].sh_size;
 425                         return (void *)ehdr + sechdrs[i].sh_offset;
 426                 }
 427         }
 428         if (size)
 429                 *size = 0;
 430         return NULL;
 431 }
 432
 433 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 434                                         const char *symname)
 435 {
 436         unsigned int i;
 437         char name[MAX_SYMNAME], *c;
 438
 439         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 440                 if (lib->dynsym[i].st_name == 0)
 441                         continue;
 442                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 443                         MAX_SYMNAME);
 444                 c = strchr(name, '@');
 445                 if (c)
 446                         *c = 0;
 447                 if (strcmp(symname, name) == 0)
 448                         return &lib->dynsym[i];
 449         }
 450         return NULL;
 451 }
 452
 453 /* Note that we assume the section is .text and the symbol is relative to
 454  * the library base
 455  */
 456 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 457                                             const char *symname)
 458 {
 459         Elf64_Sym *sym = find_symbol64(lib, symname);
 460
 461         if (sym == NULL) {
 462                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 463                        symname);
 464                 return 0;
 465         }
 466 #ifdef VDS64_HAS_DESCRIPTORS
 467         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 468                 VDSO64_LBASE;
 469 #else
 470         return sym->st_value - VDSO64_LBASE;
 471 #endif
 472 }
 473
 474 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 475                                 struct lib64_elfinfo *v64,
 476                                 const char *orig, const char *fix)
 477 {
 478         Elf64_Sym *sym64_gen, *sym64_fix;
 479
 480         sym64_gen = find_symbol64(v64, orig);
 481         if (sym64_gen == NULL) {
 482                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 483                 return -1;
 484         }
 485         if (fix == NULL) {
 486                 sym64_gen->st_name = 0;
 487                 return 0;
 488         }
 489         sym64_fix = find_symbol64(v64, fix);
 490         if (sym64_fix == NULL) {
 491                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 492                 return -1;
 493         }
 494         sym64_gen->st_value = sym64_fix->st_value;
 495         sym64_gen->st_size = sym64_fix->st_size;
 496         sym64_gen->st_info = sym64_fix->st_info;
 497         sym64_gen->st_other = sym64_fix->st_other;
 498         sym64_gen->st_shndx = sym64_fix->st_shndx;
 499
 500         return 0;
 501 }
 502
 503 #endif /* CONFIG_PPC64 */
 504
 505
 506 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 507                                         struct lib64_elfinfo *v64)
 508 {
 509         void *sect;
 510
 511         /*
 512          * Locate symbol tables & text section
 513          */
 514
 515         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 516         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 517         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 518                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 519                 return -1;
 520         }
 521         sect = find_section32(v32->hdr, ".text", NULL);
 522         if (sect == NULL) {
 523                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 524                 return -1;
 525         }
 526         v32->text = sect - vdso32_kbase;
 527
 528 #ifdef CONFIG_PPC64
 529         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 530         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 531         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 532                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 533                 return -1;
 534         }
 535         sect = find_section64(v64->hdr, ".text", NULL);
 536         if (sect == NULL) {
 537                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 538                 return -1;
 539         }
 540         v64->text = sect - vdso64_kbase;
 541 #endif /* CONFIG_PPC64 */
 542
 543         return 0;
 544 }
 545
 546 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 547                                           struct lib64_elfinfo *v64)
 548 {
 549         /*
 550          * Find signal trampolines
 551          */
 552
 553 #ifdef CONFIG_PPC64
 554         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 555 #endif
 556         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 557         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 558 }
 559
 560 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 561                                        struct lib64_elfinfo *v64)
 562 {
 563         Elf32_Sym *sym32;
 564 #ifdef CONFIG_PPC64
 565         Elf64_Sym *sym64;
 566
 567         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 568         if (sym64 == NULL) {
 569                 printk(KERN_ERR "vDSO64: Can't find symbol "
 570                        "__kernel_datapage_offset !\n");
 571                 return -1;
 572         }
 573         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 574                 (vdso64_pages << PAGE_SHIFT) -
 575                 (sym64->st_value - VDSO64_LBASE);
 576 #endif /* CONFIG_PPC64 */
 577
 578         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 579         if (sym32 == NULL) {
 580                 printk(KERN_ERR "vDSO32: Can't find symbol "
 581                        "__kernel_datapage_offset !\n");
 582                 return -1;
 583         }
 584         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 585                 (vdso32_pages << PAGE_SHIFT) -
 586                 (sym32->st_value - VDSO32_LBASE);
 587
 588         return 0;
 589 }
 590
 591
 592 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 593                                       struct lib64_elfinfo *v64)
 594 {
 595         void *start32;
 596         unsigned long size32;
 597
 598 #ifdef CONFIG_PPC64
 599         void *start64;
 600         unsigned long size64;
 601
 602         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 603         if (start64)
 604                 do_feature_fixups(cur_cpu_spec->cpu_features,
 605                                   start64, start64 + size64);
 606
 607         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 608         if (start64)
 609                 do_feature_fixups(powerpc_firmware_features,
 610                                   start64, start64 + size64);
 611 #endif /* CONFIG_PPC64 */
 612
 613         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 614         if (start32)
 615                 do_feature_fixups(cur_cpu_spec->cpu_features,
 616                                   start32, start32 + size32);
 617
 618 #ifdef CONFIG_PPC64
 619         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 620         if (start32)
 621                 do_feature_fixups(powerpc_firmware_features,
 622                                   start32, start32 + size32);
 623 #endif /* CONFIG_PPC64 */
 624
 625         return 0;
 626 }
 627
 628 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 629                                        struct lib64_elfinfo *v64)
 630 {
 631         int i;
 632
 633         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 634                 struct vdso_patch_def *patch = &vdso_patches[i];
 635                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 636                         == patch->ftr_value;
 637                 if (!match)
 638                         continue;
 639
 640                 DBG("replacing %s with %s...\n", patch->gen_name,
 641                     patch->fix_name ? "NONE" : patch->fix_name);
 642
 643                 /*
 644                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 645                  * patch the "." symbol on 64 bits.
 646                  * It would be easy to do, but doesn't seem to be necessary,
 647                  * patching the OPD symbol is enough.
 648                  */
 649                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 650                                      patch->fix_name);
 651 #ifdef CONFIG_PPC64
 652                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 653                                      patch->fix_name);
 654 #endif /* CONFIG_PPC64 */
 655         }
 656
 657         return 0;
 658 }
 659
 660
 661 static __init int vdso_setup(void)
 662 {
 663         struct lib32_elfinfo    v32;
 664         struct lib64_elfinfo    v64;
 665
 666         v32.hdr = vdso32_kbase;
 667 #ifdef CONFIG_PPC64
 668         v64.hdr = vdso64_kbase;
 669 #endif
 670         if (vdso_do_find_sections(&v32, &v64))
 671                 return -1;
 672
 673         if (vdso_fixup_datapage(&v32, &v64))
 674                 return -1;
 675
 676         if (vdso_fixup_features(&v32, &v64))
 677                 return -1;
 678
 679         if (vdso_fixup_alt_funcs(&v32, &v64))
 680                 return -1;
 681
 682         vdso_setup_trampolines(&v32, &v64);
 683
 684         return 0;
 685 }
 686
 687 /*
 688  * Called from setup_arch to initialize the bitmap of available
 689  * syscalls in the systemcfg page
 690  */
 691 static void __init vdso_setup_syscall_map(void)
 692 {
 693         unsigned int i;
 694         extern unsigned long *sys_call_table;
 695         extern unsigned long sys_ni_syscall;
 696
 697
 698         for (i = 0; i < __NR_syscalls; i++) {
 699 #ifdef CONFIG_PPC64
 700                 if (sys_call_table[i*2] != sys_ni_syscall)
 701                         vdso_data->syscall_map_64[i >> 5] |=
 702                                 0x80000000UL >> (i & 0x1f);
 703                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 704                         vdso_data->syscall_map_32[i >> 5] |=
 705                                 0x80000000UL >> (i & 0x1f);
 706 #else /* CONFIG_PPC64 */
 707                 if (sys_call_table[i] != sys_ni_syscall)
 708                         vdso_data->syscall_map_32[i >> 5] |=
 709                                 0x80000000UL >> (i & 0x1f);
 710 #endif /* CONFIG_PPC64 */
 711         }
 712 }
 713
 714
 715 void __init vdso_init(void)
 716 {
 717         int i;
 718
 719 #ifdef CONFIG_PPC64
 720         /*
 721          * Fill up the "systemcfg" stuff for backward compatiblity
 722          */
 723         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 724         vdso_data->version.major = SYSTEMCFG_MAJOR;
 725         vdso_data->version.minor = SYSTEMCFG_MINOR;
 726         vdso_data->processor = mfspr(SPRN_PVR);
 727         /*
 728          * Fake the old platform number for pSeries and iSeries and add
 729          * in LPAR bit if necessary
 730          */
 731         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 732         if (firmware_has_feature(FW_FEATURE_LPAR))
 733                 vdso_data->platform |= 1;
 734         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 735         vdso_data->dcache_size = ppc64_caches.dsize;
 736         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 737         vdso_data->icache_size = ppc64_caches.isize;
 738         vdso_data->icache_line_size = ppc64_caches.iline_size;
 739
 740         /*
 741          * Calculate the size of the 64 bits vDSO
 742          */
 743         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 744         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 745 #endif /* CONFIG_PPC64 */
 746
 747
 748         /*
 749          * Calculate the size of the 32 bits vDSO
 750          */
 751         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 752         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 753
 754
 755         /*
 756          * Setup the syscall map in the vDOS
 757          */
 758         vdso_setup_syscall_map();
 759
 760         /*
 761          * Initialize the vDSO images in memory, that is do necessary
 762          * fixups of vDSO symbols, locate trampolines, etc...
 763          */
 764         if (vdso_setup()) {
 765                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 766                 vdso32_pages = 0;
 767 #ifdef CONFIG_PPC64
 768                 vdso64_pages = 0;
 769 #endif
 770                 return;
 771         }
 772
 773         /* Make sure pages are in the correct state */
 774         for (i = 0; i < vdso32_pages; i++) {
 775                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 776                 ClearPageReserved(pg);
 777                 get_page(pg);
 778
 779         }
 780 #ifdef CONFIG_PPC64
 781         for (i = 0; i < vdso64_pages; i++) {
 782                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 783                 ClearPageReserved(pg);
 784                 get_page(pg);
 785         }
 786 #endif /* CONFIG_PPC64 */
 787
 788         get_page(virt_to_page(vdso_data));
 789 }
 790
 791 int in_gate_area_no_task(unsigned long addr)
 792 {
 793         return 0;
 794 }
 795
 796 int in_gate_area(struct task_struct *task, unsigned long addr)
 797 {
 798         return 0;
 799 }
 800
 801 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 802 {
 803         return NULL;
 804 }
 805