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 #include <linux/vs_memory.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/lmb.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 extern char vdso32_start, vdso32_end;
  54 static void *vdso32_kbase = &vdso32_start;
  55 unsigned int vdso32_pages;
  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 unsigned int vdso64_pages;
  63 unsigned long vdso64_rt_sigtramp;
  64 #endif /* CONFIG_PPC64 */
  65
  66 /*
  67  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  68  * Once the early boot kernel code no longer needs to muck around
  69  * with it, it will become dynamically allocated
  70  */
  71 static union {
  72         struct vdso_data        data;
  73         u8                      page[PAGE_SIZE];
  74 } vdso_data_store __attribute__((__section__(".data.page_aligned")));
  75 struct vdso_data *vdso_data = &vdso_data_store.data;
  76
  77 /* Format of the patch table */
  78 struct vdso_patch_def
  79 {
  80         unsigned long   ftr_mask, ftr_value;
  81         const char      *gen_name;
  82         const char      *fix_name;
  83 };
  84
  85 /* Table of functions to patch based on the CPU type/revision
  86  *
  87  * Currently, we only change sync_dicache to do nothing on processors
  88  * with a coherent icache
  89  */
  90 static struct vdso_patch_def vdso_patches[] = {
  91         {
  92                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  93                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  94         },
  95         {
  96                 CPU_FTR_USE_TB, 0,
  97                 "__kernel_gettimeofday", NULL
  98         },
  99 };
 100
 101 /*
 102  * Some infos carried around for each of them during parsing at
 103  * boot time.
 104  */
 105 struct lib32_elfinfo
 106 {
 107         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 108         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 109         unsigned long   dynsymsize;     /* size of .dynsym section */
 110         char            *dynstr;        /* ptr to .dynstr section */
 111         unsigned long   text;           /* offset of .text section in .so */
 112 };
 113
 114 struct lib64_elfinfo
 115 {
 116         Elf64_Ehdr      *hdr;
 117         Elf64_Sym       *dynsym;
 118         unsigned long   dynsymsize;
 119         char            *dynstr;
 120         unsigned long   text;
 121 };
 122
 123
 124 #ifdef __DEBUG
 125 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 126 {
 127         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 128                page_count(pg),
 129                pg->flags);
 130         if (upg/* && pg != upg*/) {
 131                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 132                                                        << PAGE_SHIFT),
 133                        page_count(upg),
 134                        upg->flags);
 135         }
 136         printk("\n");
 137 }
 138
 139 static void dump_vdso_pages(struct vm_area_struct * vma)
 140 {
 141         int i;
 142
 143         if (!vma || test_thread_flag(TIF_32BIT)) {
 144                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 145                 for (i=0; i<vdso32_pages; i++) {
 146                         struct page *pg = virt_to_page(vdso32_kbase +
 147                                                        i*PAGE_SIZE);
 148                         struct page *upg = (vma && vma->vm_mm) ?
 149                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 150                                 : NULL;
 151                         dump_one_vdso_page(pg, upg);
 152                 }
 153         }
 154         if (!vma || !test_thread_flag(TIF_32BIT)) {
 155                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 156                 for (i=0; i<vdso64_pages; i++) {
 157                         struct page *pg = virt_to_page(vdso64_kbase +
 158                                                        i*PAGE_SIZE);
 159                         struct page *upg = (vma && vma->vm_mm) ?
 160                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 161                                 : NULL;
 162                         dump_one_vdso_page(pg, upg);
 163                 }
 164         }
 165 }
 166 #endif /* DEBUG */
 167
 168 /*
 169  * Keep a dummy vma_close for now, it will prevent VMA merging.
 170  */
 171 static void vdso_vma_close(struct vm_area_struct * vma)
 172 {
 173 }
 174
 175 /*
 176  * Our nopage() function, maps in the actual vDSO kernel pages, they will
 177  * be mapped read-only by do_no_page(), and eventually COW'ed, either
 178  * right away for an initial write access, or by do_wp_page().
 179  */
 180 static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 181                                      unsigned long address, int *type)
 182 {
 183         unsigned long offset = address - vma->vm_start;
 184         struct page *pg;
 185 #ifdef CONFIG_PPC64
 186         void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
 187                 vdso64_kbase : vdso32_kbase;
 188 #else
 189         void *vbase = vdso32_kbase;
 190 #endif
 191
 192         DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
 193             current->comm, address, offset);
 194
 195         if (address < vma->vm_start || address > vma->vm_end)
 196                 return NOPAGE_SIGBUS;
 197
 198         /*
 199          * Last page is systemcfg.
 200          */
 201         if ((vma->vm_end - address) <= PAGE_SIZE)
 202                 pg = virt_to_page(vdso_data);
 203         else
 204                 pg = virt_to_page(vbase + offset);
 205
 206         get_page(pg);
 207         DBG(" ->page count: %d\n", page_count(pg));
 208
 209         return pg;
 210 }
 211
 212 static struct vm_operations_struct vdso_vmops = {
 213         .close  = vdso_vma_close,
 214         .nopage = vdso_vma_nopage,
 215 };
 216
 217 /*
 218  * This is called from binfmt_elf, we create the special vma for the
 219  * vDSO and insert it into the mm struct tree
 220  */
 221 int arch_setup_additional_pages(struct linux_binprm *bprm,
 222                                 int executable_stack, unsigned long start_code,
 223                                 unsigned long interp_map_address)
 224 {
 225         struct mm_struct *mm = current->mm;
 226         struct vm_area_struct *vma;
 227         unsigned long vdso_pages;
 228         unsigned long vdso_base;
 229         int rc;
 230
 231 #ifdef CONFIG_PPC64
 232         if (test_thread_flag(TIF_32BIT)) {
 233                 vdso_pages = vdso32_pages;
 234                 vdso_base = VDSO32_MBASE;
 235         } else {
 236                 vdso_pages = vdso64_pages;
 237                 vdso_base = VDSO64_MBASE;
 238         }
 239 #else
 240         vdso_pages = vdso32_pages;
 241         vdso_base = VDSO32_MBASE;
 242 #endif
 243
 244         current->mm->context.vdso_base = 0;
 245
 246         /* vDSO has a problem and was disabled, just don't "enable" it for the
 247          * process
 248          */
 249         if (vdso_pages == 0)
 250                 return 0;
 251         /* Add a page to the vdso size for the data page */
 252         vdso_pages ++;
 253
 254         /*
 255          * pick a base address for the vDSO in process space. We try to put it
 256          * at vdso_base which is the "natural" base for it, but we might fail
 257          * and end up putting it elsewhere.
 258          */
 259         down_write(&mm->mmap_sem);
 260         vdso_base = get_unmapped_area(NULL, vdso_base,
 261                                       vdso_pages << PAGE_SHIFT, 0, 0);
 262         if (IS_ERR_VALUE(vdso_base)) {
 263                 rc = vdso_base;
 264                 goto fail_mmapsem;
 265         }
 266
 267
 268         /* Allocate a VMA structure and fill it up */
 269         vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
 270         if (vma == NULL) {
 271                 rc = -ENOMEM;
 272                 goto fail_mmapsem;
 273         }
 274         vma->vm_mm = mm;
 275         vma->vm_start = vdso_base;
 276         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 277
 278         /*
 279          * our vma flags don't have VM_WRITE so by default, the process isn't
 280          * allowed to write those pages.
 281          * gdb can break that with ptrace interface, and thus trigger COW on
 282          * those pages but it's then your responsibility to never do that on
 283          * the "data" page of the vDSO or you'll stop getting kernel updates
 284          * and your nice userland gettimeofday will be totally dead.
 285          * It's fine to use that for setting breakpoints in the vDSO code
 286          * pages though
 287          */
 288         vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC;
 289         /*
 290          * Make sure the vDSO gets into every core dump.
 291          * Dumping its contents makes post-mortem fully interpretable later
 292          * without matching up the same kernel and hardware config to see
 293          * what PC values meant.
 294          */
 295         vma->vm_flags |= VM_ALWAYSDUMP;
 296         vma->vm_flags |= mm->def_flags;
 297         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 298         vma->vm_ops = &vdso_vmops;
 299
 300         /* Insert new VMA */
 301         rc = insert_vm_struct(mm, vma);
 302         if (rc)
 303                 goto fail_vma;
 304
 305         /* Put vDSO base into mm struct and account for memory usage */
 306         current->mm->context.vdso_base = vdso_base;
 307         vx_vmpages_add(mm, (vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
 308         up_write(&mm->mmap_sem);
 309         return 0;
 310
 311  fail_vma:
 312         kmem_cache_free(vm_area_cachep, vma);
 313  fail_mmapsem:
 314         up_write(&mm->mmap_sem);
 315         return rc;
 316 }
 317
 318 const char *arch_vma_name(struct vm_area_struct *vma)
 319 {
 320         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 321                 return "[vdso]";
 322         return NULL;
 323 }
 324
 325
 326
 327 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 328                                   unsigned long *size)
 329 {
 330         Elf32_Shdr *sechdrs;
 331         unsigned int i;
 332         char *secnames;
 333
 334         /* Grab section headers and strings so we can tell who is who */
 335         sechdrs = (void *)ehdr + ehdr->e_shoff;
 336         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 337
 338         /* Find the section they want */
 339         for (i = 1; i < ehdr->e_shnum; i++) {
 340                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 341                         if (size)
 342                                 *size = sechdrs[i].sh_size;
 343                         return (void *)ehdr + sechdrs[i].sh_offset;
 344                 }
 345         }
 346         *size = 0;
 347         return NULL;
 348 }
 349
 350 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 351                                         const char *symname)
 352 {
 353         unsigned int i;
 354         char name[MAX_SYMNAME], *c;
 355
 356         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 357                 if (lib->dynsym[i].st_name == 0)
 358                         continue;
 359                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 360                         MAX_SYMNAME);
 361                 c = strchr(name, '@');
 362                 if (c)
 363                         *c = 0;
 364                 if (strcmp(symname, name) == 0)
 365                         return &lib->dynsym[i];
 366         }
 367         return NULL;
 368 }
 369
 370 /* Note that we assume the section is .text and the symbol is relative to
 371  * the library base
 372  */
 373 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 374                                             const char *symname)
 375 {
 376         Elf32_Sym *sym = find_symbol32(lib, symname);
 377
 378         if (sym == NULL) {
 379                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 380                        symname);
 381                 return 0;
 382         }
 383         return sym->st_value - VDSO32_LBASE;
 384 }
 385
 386 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 387                                 struct lib64_elfinfo *v64,
 388                                 const char *orig, const char *fix)
 389 {
 390         Elf32_Sym *sym32_gen, *sym32_fix;
 391
 392         sym32_gen = find_symbol32(v32, orig);
 393         if (sym32_gen == NULL) {
 394                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 395                 return -1;
 396         }
 397         if (fix == NULL) {
 398                 sym32_gen->st_name = 0;
 399                 return 0;
 400         }
 401         sym32_fix = find_symbol32(v32, fix);
 402         if (sym32_fix == NULL) {
 403                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 404                 return -1;
 405         }
 406         sym32_gen->st_value = sym32_fix->st_value;
 407         sym32_gen->st_size = sym32_fix->st_size;
 408         sym32_gen->st_info = sym32_fix->st_info;
 409         sym32_gen->st_other = sym32_fix->st_other;
 410         sym32_gen->st_shndx = sym32_fix->st_shndx;
 411
 412         return 0;
 413 }
 414
 415
 416 #ifdef CONFIG_PPC64
 417
 418 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 419                                   unsigned long *size)
 420 {
 421         Elf64_Shdr *sechdrs;
 422         unsigned int i;
 423         char *secnames;
 424
 425         /* Grab section headers and strings so we can tell who is who */
 426         sechdrs = (void *)ehdr + ehdr->e_shoff;
 427         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 428
 429         /* Find the section they want */
 430         for (i = 1; i < ehdr->e_shnum; i++) {
 431                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 432                         if (size)
 433                                 *size = sechdrs[i].sh_size;
 434                         return (void *)ehdr + sechdrs[i].sh_offset;
 435                 }
 436         }
 437         if (size)
 438                 *size = 0;
 439         return NULL;
 440 }
 441
 442 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 443                                         const char *symname)
 444 {
 445         unsigned int i;
 446         char name[MAX_SYMNAME], *c;
 447
 448         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 449                 if (lib->dynsym[i].st_name == 0)
 450                         continue;
 451                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 452                         MAX_SYMNAME);
 453                 c = strchr(name, '@');
 454                 if (c)
 455                         *c = 0;
 456                 if (strcmp(symname, name) == 0)
 457                         return &lib->dynsym[i];
 458         }
 459         return NULL;
 460 }
 461
 462 /* Note that we assume the section is .text and the symbol is relative to
 463  * the library base
 464  */
 465 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 466                                             const char *symname)
 467 {
 468         Elf64_Sym *sym = find_symbol64(lib, symname);
 469
 470         if (sym == NULL) {
 471                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 472                        symname);
 473                 return 0;
 474         }
 475 #ifdef VDS64_HAS_DESCRIPTORS
 476         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 477                 VDSO64_LBASE;
 478 #else
 479         return sym->st_value - VDSO64_LBASE;
 480 #endif
 481 }
 482
 483 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 484                                 struct lib64_elfinfo *v64,
 485                                 const char *orig, const char *fix)
 486 {
 487         Elf64_Sym *sym64_gen, *sym64_fix;
 488
 489         sym64_gen = find_symbol64(v64, orig);
 490         if (sym64_gen == NULL) {
 491                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 492                 return -1;
 493         }
 494         if (fix == NULL) {
 495                 sym64_gen->st_name = 0;
 496                 return 0;
 497         }
 498         sym64_fix = find_symbol64(v64, fix);
 499         if (sym64_fix == NULL) {
 500                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 501                 return -1;
 502         }
 503         sym64_gen->st_value = sym64_fix->st_value;
 504         sym64_gen->st_size = sym64_fix->st_size;
 505         sym64_gen->st_info = sym64_fix->st_info;
 506         sym64_gen->st_other = sym64_fix->st_other;
 507         sym64_gen->st_shndx = sym64_fix->st_shndx;
 508
 509         return 0;
 510 }
 511
 512 #endif /* CONFIG_PPC64 */
 513
 514
 515 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 516                                         struct lib64_elfinfo *v64)
 517 {
 518         void *sect;
 519
 520         /*
 521          * Locate symbol tables & text section
 522          */
 523
 524         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 525         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 526         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 527                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 528                 return -1;
 529         }
 530         sect = find_section32(v32->hdr, ".text", NULL);
 531         if (sect == NULL) {
 532                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 533                 return -1;
 534         }
 535         v32->text = sect - vdso32_kbase;
 536
 537 #ifdef CONFIG_PPC64
 538         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 539         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 540         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 541                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 542                 return -1;
 543         }
 544         sect = find_section64(v64->hdr, ".text", NULL);
 545         if (sect == NULL) {
 546                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 547                 return -1;
 548         }
 549         v64->text = sect - vdso64_kbase;
 550 #endif /* CONFIG_PPC64 */
 551
 552         return 0;
 553 }
 554
 555 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 556                                           struct lib64_elfinfo *v64)
 557 {
 558         /*
 559          * Find signal trampolines
 560          */
 561
 562 #ifdef CONFIG_PPC64
 563         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 564 #endif
 565         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 566         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 567 }
 568
 569 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 570                                        struct lib64_elfinfo *v64)
 571 {
 572         Elf32_Sym *sym32;
 573 #ifdef CONFIG_PPC64
 574         Elf64_Sym *sym64;
 575
 576         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 577         if (sym64 == NULL) {
 578                 printk(KERN_ERR "vDSO64: Can't find symbol "
 579                        "__kernel_datapage_offset !\n");
 580                 return -1;
 581         }
 582         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 583                 (vdso64_pages << PAGE_SHIFT) -
 584                 (sym64->st_value - VDSO64_LBASE);
 585 #endif /* CONFIG_PPC64 */
 586
 587         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 588         if (sym32 == NULL) {
 589                 printk(KERN_ERR "vDSO32: Can't find symbol "
 590                        "__kernel_datapage_offset !\n");
 591                 return -1;
 592         }
 593         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 594                 (vdso32_pages << PAGE_SHIFT) -
 595                 (sym32->st_value - VDSO32_LBASE);
 596
 597         return 0;
 598 }
 599
 600
 601 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 602                                       struct lib64_elfinfo *v64)
 603 {
 604         void *start32;
 605         unsigned long size32;
 606
 607 #ifdef CONFIG_PPC64
 608         void *start64;
 609         unsigned long size64;
 610
 611         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 612         if (start64)
 613                 do_feature_fixups(cur_cpu_spec->cpu_features,
 614                                   start64, start64 + size64);
 615
 616         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 617         if (start64)
 618                 do_feature_fixups(powerpc_firmware_features,
 619                                   start64, start64 + size64);
 620 #endif /* CONFIG_PPC64 */
 621
 622         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 623         if (start32)
 624                 do_feature_fixups(cur_cpu_spec->cpu_features,
 625                                   start32, start32 + size32);
 626
 627 #ifdef CONFIG_PPC64
 628         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 629         if (start32)
 630                 do_feature_fixups(powerpc_firmware_features,
 631                                   start32, start32 + size32);
 632 #endif /* CONFIG_PPC64 */
 633
 634         return 0;
 635 }
 636
 637 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 638                                        struct lib64_elfinfo *v64)
 639 {
 640         int i;
 641
 642         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 643                 struct vdso_patch_def *patch = &vdso_patches[i];
 644                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 645                         == patch->ftr_value;
 646                 if (!match)
 647                         continue;
 648
 649                 DBG("replacing %s with %s...\n", patch->gen_name,
 650                     patch->fix_name ? "NONE" : patch->fix_name);
 651
 652                 /*
 653                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 654                  * patch the "." symbol on 64 bits.
 655                  * It would be easy to do, but doesn't seem to be necessary,
 656                  * patching the OPD symbol is enough.
 657                  */
 658                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 659                                      patch->fix_name);
 660 #ifdef CONFIG_PPC64
 661                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 662                                      patch->fix_name);
 663 #endif /* CONFIG_PPC64 */
 664         }
 665
 666         return 0;
 667 }
 668
 669
 670 static __init int vdso_setup(void)
 671 {
 672         struct lib32_elfinfo    v32;
 673         struct lib64_elfinfo    v64;
 674
 675         v32.hdr = vdso32_kbase;
 676 #ifdef CONFIG_PPC64
 677         v64.hdr = vdso64_kbase;
 678 #endif
 679         if (vdso_do_find_sections(&v32, &v64))
 680                 return -1;
 681
 682         if (vdso_fixup_datapage(&v32, &v64))
 683                 return -1;
 684
 685         if (vdso_fixup_features(&v32, &v64))
 686                 return -1;
 687
 688         if (vdso_fixup_alt_funcs(&v32, &v64))
 689                 return -1;
 690
 691         vdso_setup_trampolines(&v32, &v64);
 692
 693         return 0;
 694 }
 695
 696 /*
 697  * Called from setup_arch to initialize the bitmap of available
 698  * syscalls in the systemcfg page
 699  */
 700 static void __init vdso_setup_syscall_map(void)
 701 {
 702         unsigned int i;
 703         extern unsigned long *sys_call_table;
 704         extern unsigned long sys_ni_syscall;
 705
 706
 707         for (i = 0; i < __NR_syscalls; i++) {
 708 #ifdef CONFIG_PPC64
 709                 if (sys_call_table[i*2] != sys_ni_syscall)
 710                         vdso_data->syscall_map_64[i >> 5] |=
 711                                 0x80000000UL >> (i & 0x1f);
 712                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 713                         vdso_data->syscall_map_32[i >> 5] |=
 714                                 0x80000000UL >> (i & 0x1f);
 715 #else /* CONFIG_PPC64 */
 716                 if (sys_call_table[i] != sys_ni_syscall)
 717                         vdso_data->syscall_map_32[i >> 5] |=
 718                                 0x80000000UL >> (i & 0x1f);
 719 #endif /* CONFIG_PPC64 */
 720         }
 721 }
 722
 723
 724 void __init vdso_init(void)
 725 {
 726         int i;
 727
 728 #ifdef CONFIG_PPC64
 729         /*
 730          * Fill up the "systemcfg" stuff for backward compatiblity
 731          */
 732         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 733         vdso_data->version.major = SYSTEMCFG_MAJOR;
 734         vdso_data->version.minor = SYSTEMCFG_MINOR;
 735         vdso_data->processor = mfspr(SPRN_PVR);
 736         /*
 737          * Fake the old platform number for pSeries and iSeries and add
 738          * in LPAR bit if necessary
 739          */
 740         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 741         if (firmware_has_feature(FW_FEATURE_LPAR))
 742                 vdso_data->platform |= 1;
 743         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 744         vdso_data->dcache_size = ppc64_caches.dsize;
 745         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 746         vdso_data->icache_size = ppc64_caches.isize;
 747         vdso_data->icache_line_size = ppc64_caches.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 #endif /* CONFIG_PPC64 */
 755
 756
 757         /*
 758          * Calculate the size of the 32 bits vDSO
 759          */
 760         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 761         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 762
 763
 764         /*
 765          * Setup the syscall map in the vDOS
 766          */
 767         vdso_setup_syscall_map();
 768
 769         /*
 770          * Initialize the vDSO images in memory, that is do necessary
 771          * fixups of vDSO symbols, locate trampolines, etc...
 772          */
 773         if (vdso_setup()) {
 774                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 775                 vdso32_pages = 0;
 776 #ifdef CONFIG_PPC64
 777                 vdso64_pages = 0;
 778 #endif
 779                 return;
 780         }
 781
 782         /* Make sure pages are in the correct state */
 783         for (i = 0; i < vdso32_pages; i++) {
 784                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 785                 ClearPageReserved(pg);
 786                 get_page(pg);
 787
 788         }
 789 #ifdef CONFIG_PPC64
 790         for (i = 0; i < vdso64_pages; i++) {
 791                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 792                 ClearPageReserved(pg);
 793                 get_page(pg);
 794         }
 795 #endif /* CONFIG_PPC64 */
 796
 797         get_page(virt_to_page(vdso_data));
 798 }
 799
 800 int in_gate_area_no_task(unsigned long addr)
 801 {
 802         return 0;
 803 }
 804
 805 int in_gate_area(struct task_struct *task, unsigned long addr)
 806 {
 807         return 0;
 808 }
 809
 810 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 811 {
 812         return NULL;
 813 }
 814