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/module.h>
  13 #include <linux/errno.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/mm.h>
  17 #include <linux/smp.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 #include <linux/memblock.h>
  26
  27 #include <asm/pgtable.h>
  28 #include <asm/system.h>
  29 #include <asm/processor.h>
  30 #include <asm/mmu.h>
  31 #include <asm/mmu_context.h>
  32 #include <asm/prom.h>
  33 #include <asm/machdep.h>
  34 #include <asm/cputable.h>
  35 #include <asm/sections.h>
  36 #include <asm/firmware.h>
  37 #include <asm/vdso.h>
  38 #include <asm/vdso_datapage.h>
  39
  40 #include "setup.h"
  41
  42 #undef DEBUG
  43
  44 #ifdef DEBUG
  45 #define DBG(fmt...) printk(fmt)
  46 #else
  47 #define DBG(fmt...)
  48 #endif
  49
  50 /* Max supported size for symbol names */
  51 #define MAX_SYMNAME     64
  52
  53 /* The alignment of the vDSO */
  54 #define VDSO_ALIGNMENT  (1 << 16)
  55
  56 extern char vdso32_start, vdso32_end;
  57 static void *vdso32_kbase = &vdso32_start;
  58 static unsigned int vdso32_pages;
  59 static struct page **vdso32_pagelist;
  60 unsigned long vdso32_sigtramp;
  61 unsigned long vdso32_rt_sigtramp;
  62
  63 #ifdef CONFIG_PPC64
  64 extern char vdso64_start, vdso64_end;
  65 static void *vdso64_kbase = &vdso64_start;
  66 static unsigned int vdso64_pages;
  67 static struct page **vdso64_pagelist;
  68 unsigned long vdso64_rt_sigtramp;
  69 #endif /* CONFIG_PPC64 */
  70
  71 static int vdso_ready;
  72
  73 /*
  74  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  75  * Once the early boot kernel code no longer needs to muck around
  76  * with it, it will become dynamically allocated
  77  */
  78 static union {
  79         struct vdso_data        data;
  80         u8                      page[PAGE_SIZE];
  81 } vdso_data_store __page_aligned_data;
  82 struct vdso_data *vdso_data = &vdso_data_store.data;
  83
  84 /* Format of the patch table */
  85 struct vdso_patch_def
  86 {
  87         unsigned long   ftr_mask, ftr_value;
  88         const char      *gen_name;
  89         const char      *fix_name;
  90 };
  91
  92 /* Table of functions to patch based on the CPU type/revision
  93  *
  94  * Currently, we only change sync_dicache to do nothing on processors
  95  * with a coherent icache
  96  */
  97 static struct vdso_patch_def vdso_patches[] = {
  98         {
  99                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
 100                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
 101         },
 102         {
 103                 CPU_FTR_USE_TB, 0,
 104                 "__kernel_gettimeofday", NULL
 105         },
 106         {
 107                 CPU_FTR_USE_TB, 0,
 108                 "__kernel_clock_gettime", NULL
 109         },
 110         {
 111                 CPU_FTR_USE_TB, 0,
 112                 "__kernel_clock_getres", NULL
 113         },
 114         {
 115                 CPU_FTR_USE_TB, 0,
 116                 "__kernel_get_tbfreq", NULL
 117         },
 118 };
 119
 120 /*
 121  * Some infos carried around for each of them during parsing at
 122  * boot time.
 123  */
 124 struct lib32_elfinfo
 125 {
 126         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 127         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 128         unsigned long   dynsymsize;     /* size of .dynsym section */
 129         char            *dynstr;        /* ptr to .dynstr section */
 130         unsigned long   text;           /* offset of .text section in .so */
 131 };
 132
 133 struct lib64_elfinfo
 134 {
 135         Elf64_Ehdr      *hdr;
 136         Elf64_Sym       *dynsym;
 137         unsigned long   dynsymsize;
 138         char            *dynstr;
 139         unsigned long   text;
 140 };
 141
 142
 143 #ifdef __DEBUG
 144 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 145 {
 146         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 147                page_count(pg),
 148                pg->flags);
 149         if (upg && !IS_ERR(upg) /* && pg != upg*/) {
 150                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 151                                                        << PAGE_SHIFT),
 152                        page_count(upg),
 153                        upg->flags);
 154         }
 155         printk("\n");
 156 }
 157
 158 static void dump_vdso_pages(struct vm_area_struct * vma)
 159 {
 160         int i;
 161
 162         if (!vma || is_32bit_task()) {
 163                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 164                 for (i=0; i<vdso32_pages; i++) {
 165                         struct page *pg = virt_to_page(vdso32_kbase +
 166                                                        i*PAGE_SIZE);
 167                         struct page *upg = (vma && vma->vm_mm) ?
 168                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 169                                 : NULL;
 170                         dump_one_vdso_page(pg, upg);
 171                 }
 172         }
 173         if (!vma || !is_32bit_task()) {
 174                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 175                 for (i=0; i<vdso64_pages; i++) {
 176                         struct page *pg = virt_to_page(vdso64_kbase +
 177                                                        i*PAGE_SIZE);
 178                         struct page *upg = (vma && vma->vm_mm) ?
 179                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 180                                 : NULL;
 181                         dump_one_vdso_page(pg, upg);
 182                 }
 183         }
 184 }
 185 #endif /* DEBUG */
 186
 187 /*
 188  * This is called from binfmt_elf, we create the special vma for the
 189  * vDSO and insert it into the mm struct tree
 190  */
 191 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 192 {
 193         struct mm_struct *mm = current->mm;
 194         struct page **vdso_pagelist;
 195         unsigned long vdso_pages;
 196         unsigned long vdso_base;
 197         int rc;
 198
 199         if (!vdso_ready)
 200                 return 0;
 201
 202 #ifdef CONFIG_PPC64
 203         if (is_32bit_task()) {
 204                 vdso_pagelist = vdso32_pagelist;
 205                 vdso_pages = vdso32_pages;
 206                 vdso_base = VDSO32_MBASE;
 207         } else {
 208                 vdso_pagelist = vdso64_pagelist;
 209                 vdso_pages = vdso64_pages;
 210                 /*
 211                  * On 64bit we don't have a preferred map address. This
 212                  * allows get_unmapped_area to find an area near other mmaps
 213                  * and most likely share a SLB entry.
 214                  */
 215                 vdso_base = 0;
 216         }
 217 #else
 218         vdso_pagelist = vdso32_pagelist;
 219         vdso_pages = vdso32_pages;
 220         vdso_base = VDSO32_MBASE;
 221 #endif
 222
 223         current->mm->context.vdso_base = 0;
 224
 225         /* vDSO has a problem and was disabled, just don't "enable" it for the
 226          * process
 227          */
 228         if (vdso_pages == 0)
 229                 return 0;
 230         /* Add a page to the vdso size for the data page */
 231         vdso_pages ++;
 232
 233         /*
 234          * pick a base address for the vDSO in process space. We try to put it
 235          * at vdso_base which is the "natural" base for it, but we might fail
 236          * and end up putting it elsewhere.
 237          * Add enough to the size so that the result can be aligned.
 238          */
 239         down_write(&mm->mmap_sem);
 240         vdso_base = get_unmapped_area(NULL, vdso_base,
 241                                       (vdso_pages << PAGE_SHIFT) +
 242                                       ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 243                                       0, 0);
 244         if (IS_ERR_VALUE(vdso_base)) {
 245                 rc = vdso_base;
 246                 goto fail_mmapsem;
 247         }
 248
 249         /* Add required alignment. */
 250         vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
 251
 252         /*
 253          * Put vDSO base into mm struct. We need to do this before calling
 254          * install_special_mapping or the perf counter mmap tracking code
 255          * will fail to recognise it as a vDSO (since arch_vma_name fails).
 256          */
 257         current->mm->context.vdso_base = vdso_base;
 258
 259         /*
 260          * our vma flags don't have VM_WRITE so by default, the process isn't
 261          * allowed to write those pages.
 262          * gdb can break that with ptrace interface, and thus trigger COW on
 263          * those pages but it's then your responsibility to never do that on
 264          * the "data" page of the vDSO or you'll stop getting kernel updates
 265          * and your nice userland gettimeofday will be totally dead.
 266          * It's fine to use that for setting breakpoints in the vDSO code
 267          * pages though
 268          *
 269          * Make sure the vDSO gets into every core dump.
 270          * Dumping its contents makes post-mortem fully interpretable later
 271          * without matching up the same kernel and hardware config to see
 272          * what PC values meant.
 273          */
 274         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 275                                      VM_READ|VM_EXEC|
 276                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
 277                                      VM_ALWAYSDUMP,
 278                                      vdso_pagelist);
 279         if (rc) {
 280                 current->mm->context.vdso_base = 0;
 281                 goto fail_mmapsem;
 282         }
 283
 284         up_write(&mm->mmap_sem);
 285         return 0;
 286
 287  fail_mmapsem:
 288         up_write(&mm->mmap_sem);
 289         return rc;
 290 }
 291
 292 const char *arch_vma_name(struct vm_area_struct *vma)
 293 {
 294         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 295                 return "[vdso]";
 296         return NULL;
 297 }
 298
 299
 300
 301 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 302                                   unsigned long *size)
 303 {
 304         Elf32_Shdr *sechdrs;
 305         unsigned int i;
 306         char *secnames;
 307
 308         /* Grab section headers and strings so we can tell who is who */
 309         sechdrs = (void *)ehdr + ehdr->e_shoff;
 310         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 311
 312         /* Find the section they want */
 313         for (i = 1; i < ehdr->e_shnum; i++) {
 314                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 315                         if (size)
 316                                 *size = sechdrs[i].sh_size;
 317                         return (void *)ehdr + sechdrs[i].sh_offset;
 318                 }
 319         }
 320         *size = 0;
 321         return NULL;
 322 }
 323
 324 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 325                                         const char *symname)
 326 {
 327         unsigned int i;
 328         char name[MAX_SYMNAME], *c;
 329
 330         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 331                 if (lib->dynsym[i].st_name == 0)
 332                         continue;
 333                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 334                         MAX_SYMNAME);
 335                 c = strchr(name, '@');
 336                 if (c)
 337                         *c = 0;
 338                 if (strcmp(symname, name) == 0)
 339                         return &lib->dynsym[i];
 340         }
 341         return NULL;
 342 }
 343
 344 /* Note that we assume the section is .text and the symbol is relative to
 345  * the library base
 346  */
 347 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 348                                             const char *symname)
 349 {
 350         Elf32_Sym *sym = find_symbol32(lib, symname);
 351
 352         if (sym == NULL) {
 353                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 354                        symname);
 355                 return 0;
 356         }
 357         return sym->st_value - VDSO32_LBASE;
 358 }
 359
 360 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 361                                        struct lib64_elfinfo *v64,
 362                                        const char *orig, const char *fix)
 363 {
 364         Elf32_Sym *sym32_gen, *sym32_fix;
 365
 366         sym32_gen = find_symbol32(v32, orig);
 367         if (sym32_gen == NULL) {
 368                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 369                 return -1;
 370         }
 371         if (fix == NULL) {
 372                 sym32_gen->st_name = 0;
 373                 return 0;
 374         }
 375         sym32_fix = find_symbol32(v32, fix);
 376         if (sym32_fix == NULL) {
 377                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 378                 return -1;
 379         }
 380         sym32_gen->st_value = sym32_fix->st_value;
 381         sym32_gen->st_size = sym32_fix->st_size;
 382         sym32_gen->st_info = sym32_fix->st_info;
 383         sym32_gen->st_other = sym32_fix->st_other;
 384         sym32_gen->st_shndx = sym32_fix->st_shndx;
 385
 386         return 0;
 387 }
 388
 389
 390 #ifdef CONFIG_PPC64
 391
 392 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 393                                   unsigned long *size)
 394 {
 395         Elf64_Shdr *sechdrs;
 396         unsigned int i;
 397         char *secnames;
 398
 399         /* Grab section headers and strings so we can tell who is who */
 400         sechdrs = (void *)ehdr + ehdr->e_shoff;
 401         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 402
 403         /* Find the section they want */
 404         for (i = 1; i < ehdr->e_shnum; i++) {
 405                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 406                         if (size)
 407                                 *size = sechdrs[i].sh_size;
 408                         return (void *)ehdr + sechdrs[i].sh_offset;
 409                 }
 410         }
 411         if (size)
 412                 *size = 0;
 413         return NULL;
 414 }
 415
 416 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 417                                         const char *symname)
 418 {
 419         unsigned int i;
 420         char name[MAX_SYMNAME], *c;
 421
 422         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 423                 if (lib->dynsym[i].st_name == 0)
 424                         continue;
 425                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 426                         MAX_SYMNAME);
 427                 c = strchr(name, '@');
 428                 if (c)
 429                         *c = 0;
 430                 if (strcmp(symname, name) == 0)
 431                         return &lib->dynsym[i];
 432         }
 433         return NULL;
 434 }
 435
 436 /* Note that we assume the section is .text and the symbol is relative to
 437  * the library base
 438  */
 439 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 440                                             const char *symname)
 441 {
 442         Elf64_Sym *sym = find_symbol64(lib, symname);
 443
 444         if (sym == NULL) {
 445                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 446                        symname);
 447                 return 0;
 448         }
 449 #ifdef VDS64_HAS_DESCRIPTORS
 450         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 451                 VDSO64_LBASE;
 452 #else
 453         return sym->st_value - VDSO64_LBASE;
 454 #endif
 455 }
 456
 457 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 458                                        struct lib64_elfinfo *v64,
 459                                        const char *orig, const char *fix)
 460 {
 461         Elf64_Sym *sym64_gen, *sym64_fix;
 462
 463         sym64_gen = find_symbol64(v64, orig);
 464         if (sym64_gen == NULL) {
 465                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 466                 return -1;
 467         }
 468         if (fix == NULL) {
 469                 sym64_gen->st_name = 0;
 470                 return 0;
 471         }
 472         sym64_fix = find_symbol64(v64, fix);
 473         if (sym64_fix == NULL) {
 474                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 475                 return -1;
 476         }
 477         sym64_gen->st_value = sym64_fix->st_value;
 478         sym64_gen->st_size = sym64_fix->st_size;
 479         sym64_gen->st_info = sym64_fix->st_info;
 480         sym64_gen->st_other = sym64_fix->st_other;
 481         sym64_gen->st_shndx = sym64_fix->st_shndx;
 482
 483         return 0;
 484 }
 485
 486 #endif /* CONFIG_PPC64 */
 487
 488
 489 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 490                                         struct lib64_elfinfo *v64)
 491 {
 492         void *sect;
 493
 494         /*
 495          * Locate symbol tables & text section
 496          */
 497
 498         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 499         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 500         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 501                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 502                 return -1;
 503         }
 504         sect = find_section32(v32->hdr, ".text", NULL);
 505         if (sect == NULL) {
 506                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 507                 return -1;
 508         }
 509         v32->text = sect - vdso32_kbase;
 510
 511 #ifdef CONFIG_PPC64
 512         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 513         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 514         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 515                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 516                 return -1;
 517         }
 518         sect = find_section64(v64->hdr, ".text", NULL);
 519         if (sect == NULL) {
 520                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 521                 return -1;
 522         }
 523         v64->text = sect - vdso64_kbase;
 524 #endif /* CONFIG_PPC64 */
 525
 526         return 0;
 527 }
 528
 529 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 530                                           struct lib64_elfinfo *v64)
 531 {
 532         /*
 533          * Find signal trampolines
 534          */
 535
 536 #ifdef CONFIG_PPC64
 537         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 538 #endif
 539         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 540         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 541 }
 542
 543 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 544                                        struct lib64_elfinfo *v64)
 545 {
 546         Elf32_Sym *sym32;
 547 #ifdef CONFIG_PPC64
 548         Elf64_Sym *sym64;
 549
 550         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 551         if (sym64 == NULL) {
 552                 printk(KERN_ERR "vDSO64: Can't find symbol "
 553                        "__kernel_datapage_offset !\n");
 554                 return -1;
 555         }
 556         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 557                 (vdso64_pages << PAGE_SHIFT) -
 558                 (sym64->st_value - VDSO64_LBASE);
 559 #endif /* CONFIG_PPC64 */
 560
 561         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 562         if (sym32 == NULL) {
 563                 printk(KERN_ERR "vDSO32: Can't find symbol "
 564                        "__kernel_datapage_offset !\n");
 565                 return -1;
 566         }
 567         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 568                 (vdso32_pages << PAGE_SHIFT) -
 569                 (sym32->st_value - VDSO32_LBASE);
 570
 571         return 0;
 572 }
 573
 574
 575 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 576                                       struct lib64_elfinfo *v64)
 577 {
 578         void *start32;
 579         unsigned long size32;
 580
 581 #ifdef CONFIG_PPC64
 582         void *start64;
 583         unsigned long size64;
 584
 585         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 586         if (start64)
 587                 do_feature_fixups(cur_cpu_spec->cpu_features,
 588                                   start64, start64 + size64);
 589
 590         start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
 591         if (start64)
 592                 do_feature_fixups(cur_cpu_spec->mmu_features,
 593                                   start64, start64 + size64);
 594
 595         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 596         if (start64)
 597                 do_feature_fixups(powerpc_firmware_features,
 598                                   start64, start64 + size64);
 599
 600         start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
 601         if (start64)
 602                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 603                                  start64, start64 + size64);
 604 #endif /* CONFIG_PPC64 */
 605
 606         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 607         if (start32)
 608                 do_feature_fixups(cur_cpu_spec->cpu_features,
 609                                   start32, start32 + size32);
 610
 611         start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
 612         if (start32)
 613                 do_feature_fixups(cur_cpu_spec->mmu_features,
 614                                   start32, start32 + size32);
 615
 616 #ifdef CONFIG_PPC64
 617         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 618         if (start32)
 619                 do_feature_fixups(powerpc_firmware_features,
 620                                   start32, start32 + size32);
 621 #endif /* CONFIG_PPC64 */
 622
 623         start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
 624         if (start32)
 625                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 626                                  start32, start32 + size32);
 627
 628         return 0;
 629 }
 630
 631 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 632                                        struct lib64_elfinfo *v64)
 633 {
 634         int i;
 635
 636         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 637                 struct vdso_patch_def *patch = &vdso_patches[i];
 638                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 639                         == patch->ftr_value;
 640                 if (!match)
 641                         continue;
 642
 643                 DBG("replacing %s with %s...\n", patch->gen_name,
 644                     patch->fix_name ? "NONE" : patch->fix_name);
 645
 646                 /*
 647                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 648                  * patch the "." symbol on 64 bits.
 649                  * It would be easy to do, but doesn't seem to be necessary,
 650                  * patching the OPD symbol is enough.
 651                  */
 652                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 653                                      patch->fix_name);
 654 #ifdef CONFIG_PPC64
 655                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 656                                      patch->fix_name);
 657 #endif /* CONFIG_PPC64 */
 658         }
 659
 660         return 0;
 661 }
 662
 663
 664 static __init int vdso_setup(void)
 665 {
 666         struct lib32_elfinfo    v32;
 667         struct lib64_elfinfo    v64;
 668
 669         v32.hdr = vdso32_kbase;
 670 #ifdef CONFIG_PPC64
 671         v64.hdr = vdso64_kbase;
 672 #endif
 673         if (vdso_do_find_sections(&v32, &v64))
 674                 return -1;
 675
 676         if (vdso_fixup_datapage(&v32, &v64))
 677                 return -1;
 678
 679         if (vdso_fixup_features(&v32, &v64))
 680                 return -1;
 681
 682         if (vdso_fixup_alt_funcs(&v32, &v64))
 683                 return -1;
 684
 685         vdso_setup_trampolines(&v32, &v64);
 686
 687         return 0;
 688 }
 689
 690 /*
 691  * Called from setup_arch to initialize the bitmap of available
 692  * syscalls in the systemcfg page
 693  */
 694 static void __init vdso_setup_syscall_map(void)
 695 {
 696         unsigned int i;
 697         extern unsigned long *sys_call_table;
 698         extern unsigned long sys_ni_syscall;
 699
 700
 701         for (i = 0; i < __NR_syscalls; i++) {
 702 #ifdef CONFIG_PPC64
 703                 if (sys_call_table[i*2] != sys_ni_syscall)
 704                         vdso_data->syscall_map_64[i >> 5] |=
 705                                 0x80000000UL >> (i & 0x1f);
 706                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 707                         vdso_data->syscall_map_32[i >> 5] |=
 708                                 0x80000000UL >> (i & 0x1f);
 709 #else /* CONFIG_PPC64 */
 710                 if (sys_call_table[i] != sys_ni_syscall)
 711                         vdso_data->syscall_map_32[i >> 5] |=
 712                                 0x80000000UL >> (i & 0x1f);
 713 #endif /* CONFIG_PPC64 */
 714         }
 715 }
 716
 717
 718 static int __init vdso_init(void)
 719 {
 720         int i;
 721
 722 #ifdef CONFIG_PPC64
 723         /*
 724          * Fill up the "systemcfg" stuff for backward compatibility
 725          */
 726         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 727         vdso_data->version.major = SYSTEMCFG_MAJOR;
 728         vdso_data->version.minor = SYSTEMCFG_MINOR;
 729         vdso_data->processor = mfspr(SPRN_PVR);
 730         /*
 731          * Fake the old platform number for pSeries and iSeries and add
 732          * in LPAR bit if necessary
 733          */
 734         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 735         if (firmware_has_feature(FW_FEATURE_LPAR))
 736                 vdso_data->platform |= 1;
 737         vdso_data->physicalMemorySize = memblock_phys_mem_size();
 738         vdso_data->dcache_size = ppc64_caches.dsize;
 739         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 740         vdso_data->icache_size = ppc64_caches.isize;
 741         vdso_data->icache_line_size = ppc64_caches.iline_size;
 742
 743         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
 744         vdso_data->dcache_block_size = ppc64_caches.dline_size;
 745         vdso_data->icache_block_size = ppc64_caches.iline_size;
 746         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
 747         vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
 748
 749         /*
 750          * Calculate the size of the 64 bits vDSO
 751          */
 752         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 753         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 754 #else
 755         vdso_data->dcache_block_size = L1_CACHE_BYTES;
 756         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
 757         vdso_data->icache_block_size = L1_CACHE_BYTES;
 758         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
 759 #endif /* CONFIG_PPC64 */
 760
 761
 762         /*
 763          * Calculate the size of the 32 bits vDSO
 764          */
 765         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 766         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 767
 768
 769         /*
 770          * Setup the syscall map in the vDOS
 771          */
 772         vdso_setup_syscall_map();
 773
 774         /*
 775          * Initialize the vDSO images in memory, that is do necessary
 776          * fixups of vDSO symbols, locate trampolines, etc...
 777          */
 778         if (vdso_setup()) {
 779                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 780                 vdso32_pages = 0;
 781 #ifdef CONFIG_PPC64
 782                 vdso64_pages = 0;
 783 #endif
 784                 return 0;
 785         }
 786
 787         /* Make sure pages are in the correct state */
 788         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 789                                   GFP_KERNEL);
 790         BUG_ON(vdso32_pagelist == NULL);
 791         for (i = 0; i < vdso32_pages; i++) {
 792                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 793                 ClearPageReserved(pg);
 794                 get_page(pg);
 795                 vdso32_pagelist[i] = pg;
 796         }
 797         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 798         vdso32_pagelist[i] = NULL;
 799
 800 #ifdef CONFIG_PPC64
 801         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 802                                   GFP_KERNEL);
 803         BUG_ON(vdso64_pagelist == NULL);
 804         for (i = 0; i < vdso64_pages; i++) {
 805                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 806                 ClearPageReserved(pg);
 807                 get_page(pg);
 808                 vdso64_pagelist[i] = pg;
 809         }
 810         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 811         vdso64_pagelist[i] = NULL;
 812 #endif /* CONFIG_PPC64 */
 813
 814         get_page(virt_to_page(vdso_data));
 815
 816         smp_wmb();
 817         vdso_ready = 1;
 818
 819         return 0;
 820 }
 821 arch_initcall(vdso_init);
 822
 823 int in_gate_area_no_mm(unsigned long addr)
 824 {
 825         return 0;
 826 }
 827
 828 int in_gate_area(struct mm_struct *mm, unsigned long addr)
 829 {
 830         return 0;
 831 }
 832
 833 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
 834 {
 835         return NULL;
 836 }
 837