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/config.h>
  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/smp_lock.h>
  19 #include <linux/stddef.h>
  20 #include <linux/unistd.h>
  21 #include <linux/slab.h>
  22 #include <linux/user.h>
  23 #include <linux/elf.h>
  24 #include <linux/security.h>
  25 #include <linux/bootmem.h>
  26 #include <linux/vs_memory.h>
  27
  28 #include <asm/pgtable.h>
  29 #include <asm/system.h>
  30 #include <asm/processor.h>
  31 #include <asm/mmu.h>
  32 #include <asm/mmu_context.h>
  33 #include <asm/lmb.h>
  34 #include <asm/machdep.h>
  35 #include <asm/cputable.h>
  36 #include <asm/sections.h>
  37 #include <asm/firmware.h>
  38 #include <asm/vdso.h>
  39 #include <asm/vdso_datapage.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, unsigned long start_code,
 222                                 unsigned long interp_map_address)
 223 {
 224         struct mm_struct *mm = current->mm;
 225         struct vm_area_struct *vma;
 226         unsigned long vdso_pages;
 227         unsigned long vdso_base;
 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->thread.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
 250         vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
 251         if (vma == NULL)
 252                 return -ENOMEM;
 253
 254         memset(vma, 0, sizeof(*vma));
 255
 256         /* Add a page to the vdso size for the data page */
 257         vdso_pages ++;
 258
 259         /*
 260          * pick a base address for the vDSO in process space. We try to put it
 261          * at vdso_base which is the "natural" base for it, but we might fail
 262          * and end up putting it elsewhere.
 263          */
 264         vdso_base = get_unmapped_area(NULL, vdso_base,
 265                                       vdso_pages << PAGE_SHIFT, 0, 0);
 266         if (vdso_base & ~PAGE_MASK) {
 267                 kmem_cache_free(vm_area_cachep, vma);
 268                 return (int)vdso_base;
 269         }
 270
 271         current->thread.vdso_base = vdso_base;
 272
 273         vma->vm_mm = mm;
 274         vma->vm_start = current->thread.vdso_base;
 275         vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
 276
 277         /*
 278          * our vma flags don't have VM_WRITE so by default, the process isn't
 279          * allowed to write those pages.
 280          * gdb can break that with ptrace interface, and thus trigger COW on
 281          * those pages but it's then your responsibility to never do that on
 282          * the "data" page of the vDSO or you'll stop getting kernel updates
 283          * and your nice userland gettimeofday will be totally dead.
 284          * It's fine to use that for setting breakpoints in the vDSO code
 285          * pages though
 286          */
 287         vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 288         vma->vm_flags |= mm->def_flags;
 289         vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
 290         vma->vm_ops = &vdso_vmops;
 291
 292         down_write(&mm->mmap_sem);
 293         if (insert_vm_struct(mm, vma)) {
 294                 up_write(&mm->mmap_sem);
 295                 kmem_cache_free(vm_area_cachep, vma);
 296                 return -ENOMEM;
 297         }
 298         vx_vmpages_add(mm, (vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
 299         up_write(&mm->mmap_sem);
 300
 301         return 0;
 302 }
 303
 304 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 305                                   unsigned long *size)
 306 {
 307         Elf32_Shdr *sechdrs;
 308         unsigned int i;
 309         char *secnames;
 310
 311         /* Grab section headers and strings so we can tell who is who */
 312         sechdrs = (void *)ehdr + ehdr->e_shoff;
 313         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 314
 315         /* Find the section they want */
 316         for (i = 1; i < ehdr->e_shnum; i++) {
 317                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 318                         if (size)
 319                                 *size = sechdrs[i].sh_size;
 320                         return (void *)ehdr + sechdrs[i].sh_offset;
 321                 }
 322         }
 323         *size = 0;
 324         return NULL;
 325 }
 326
 327 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 328                                         const char *symname)
 329 {
 330         unsigned int i;
 331         char name[MAX_SYMNAME], *c;
 332
 333         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 334                 if (lib->dynsym[i].st_name == 0)
 335                         continue;
 336                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 337                         MAX_SYMNAME);
 338                 c = strchr(name, '@');
 339                 if (c)
 340                         *c = 0;
 341                 if (strcmp(symname, name) == 0)
 342                         return &lib->dynsym[i];
 343         }
 344         return NULL;
 345 }
 346
 347 /* Note that we assume the section is .text and the symbol is relative to
 348  * the library base
 349  */
 350 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 351                                             const char *symname)
 352 {
 353         Elf32_Sym *sym = find_symbol32(lib, symname);
 354
 355         if (sym == NULL) {
 356                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 357                        symname);
 358                 return 0;
 359         }
 360         return sym->st_value - VDSO32_LBASE;
 361 }
 362
 363 static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
 364                                 struct lib64_elfinfo *v64,
 365                                 const char *orig, const char *fix)
 366 {
 367         Elf32_Sym *sym32_gen, *sym32_fix;
 368
 369         sym32_gen = find_symbol32(v32, orig);
 370         if (sym32_gen == NULL) {
 371                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 372                 return -1;
 373         }
 374         if (fix == NULL) {
 375                 sym32_gen->st_name = 0;
 376                 return 0;
 377         }
 378         sym32_fix = find_symbol32(v32, fix);
 379         if (sym32_fix == NULL) {
 380                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 381                 return -1;
 382         }
 383         sym32_gen->st_value = sym32_fix->st_value;
 384         sym32_gen->st_size = sym32_fix->st_size;
 385         sym32_gen->st_info = sym32_fix->st_info;
 386         sym32_gen->st_other = sym32_fix->st_other;
 387         sym32_gen->st_shndx = sym32_fix->st_shndx;
 388
 389         return 0;
 390 }
 391
 392
 393 #ifdef CONFIG_PPC64
 394
 395 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 396                                   unsigned long *size)
 397 {
 398         Elf64_Shdr *sechdrs;
 399         unsigned int i;
 400         char *secnames;
 401
 402         /* Grab section headers and strings so we can tell who is who */
 403         sechdrs = (void *)ehdr + ehdr->e_shoff;
 404         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 405
 406         /* Find the section they want */
 407         for (i = 1; i < ehdr->e_shnum; i++) {
 408                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 409                         if (size)
 410                                 *size = sechdrs[i].sh_size;
 411                         return (void *)ehdr + sechdrs[i].sh_offset;
 412                 }
 413         }
 414         if (size)
 415                 *size = 0;
 416         return NULL;
 417 }
 418
 419 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 420                                         const char *symname)
 421 {
 422         unsigned int i;
 423         char name[MAX_SYMNAME], *c;
 424
 425         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 426                 if (lib->dynsym[i].st_name == 0)
 427                         continue;
 428                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 429                         MAX_SYMNAME);
 430                 c = strchr(name, '@');
 431                 if (c)
 432                         *c = 0;
 433                 if (strcmp(symname, name) == 0)
 434                         return &lib->dynsym[i];
 435         }
 436         return NULL;
 437 }
 438
 439 /* Note that we assume the section is .text and the symbol is relative to
 440  * the library base
 441  */
 442 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 443                                             const char *symname)
 444 {
 445         Elf64_Sym *sym = find_symbol64(lib, symname);
 446
 447         if (sym == NULL) {
 448                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 449                        symname);
 450                 return 0;
 451         }
 452 #ifdef VDS64_HAS_DESCRIPTORS
 453         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 454                 VDSO64_LBASE;
 455 #else
 456         return sym->st_value - VDSO64_LBASE;
 457 #endif
 458 }
 459
 460 static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
 461                                 struct lib64_elfinfo *v64,
 462                                 const char *orig, const char *fix)
 463 {
 464         Elf64_Sym *sym64_gen, *sym64_fix;
 465
 466         sym64_gen = find_symbol64(v64, orig);
 467         if (sym64_gen == NULL) {
 468                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 469                 return -1;
 470         }
 471         if (fix == NULL) {
 472                 sym64_gen->st_name = 0;
 473                 return 0;
 474         }
 475         sym64_fix = find_symbol64(v64, fix);
 476         if (sym64_fix == NULL) {
 477                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 478                 return -1;
 479         }
 480         sym64_gen->st_value = sym64_fix->st_value;
 481         sym64_gen->st_size = sym64_fix->st_size;
 482         sym64_gen->st_info = sym64_fix->st_info;
 483         sym64_gen->st_other = sym64_fix->st_other;
 484         sym64_gen->st_shndx = sym64_fix->st_shndx;
 485
 486         return 0;
 487 }
 488
 489 #endif /* CONFIG_PPC64 */
 490
 491
 492 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 493                                         struct lib64_elfinfo *v64)
 494 {
 495         void *sect;
 496
 497         /*
 498          * Locate symbol tables & text section
 499          */
 500
 501         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 502         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 503         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 504                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 505                 return -1;
 506         }
 507         sect = find_section32(v32->hdr, ".text", NULL);
 508         if (sect == NULL) {
 509                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 510                 return -1;
 511         }
 512         v32->text = sect - vdso32_kbase;
 513
 514 #ifdef CONFIG_PPC64
 515         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 516         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 517         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 518                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 519                 return -1;
 520         }
 521         sect = find_section64(v64->hdr, ".text", NULL);
 522         if (sect == NULL) {
 523                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 524                 return -1;
 525         }
 526         v64->text = sect - vdso64_kbase;
 527 #endif /* CONFIG_PPC64 */
 528
 529         return 0;
 530 }
 531
 532 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 533                                           struct lib64_elfinfo *v64)
 534 {
 535         /*
 536          * Find signal trampolines
 537          */
 538
 539 #ifdef CONFIG_PPC64
 540         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 541 #endif
 542         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 543         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 544 }
 545
 546 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 547                                        struct lib64_elfinfo *v64)
 548 {
 549         Elf32_Sym *sym32;
 550 #ifdef CONFIG_PPC64
 551         Elf64_Sym *sym64;
 552
 553         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 554         if (sym64 == NULL) {
 555                 printk(KERN_ERR "vDSO64: Can't find symbol "
 556                        "__kernel_datapage_offset !\n");
 557                 return -1;
 558         }
 559         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 560                 (vdso64_pages << PAGE_SHIFT) -
 561                 (sym64->st_value - VDSO64_LBASE);
 562 #endif /* CONFIG_PPC64 */
 563
 564         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 565         if (sym32 == NULL) {
 566                 printk(KERN_ERR "vDSO32: Can't find symbol "
 567                        "__kernel_datapage_offset !\n");
 568                 return -1;
 569         }
 570         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 571                 (vdso32_pages << PAGE_SHIFT) -
 572                 (sym32->st_value - VDSO32_LBASE);
 573
 574         return 0;
 575 }
 576
 577 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 578                                        struct lib64_elfinfo *v64)
 579 {
 580         int i;
 581
 582         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 583                 struct vdso_patch_def *patch = &vdso_patches[i];
 584                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 585                         == patch->ftr_value;
 586                 if (!match)
 587                         continue;
 588
 589                 DBG("replacing %s with %s...\n", patch->gen_name,
 590                     patch->fix_name ? "NONE" : patch->fix_name);
 591
 592                 /*
 593                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 594                  * patch the "." symbol on 64 bits.
 595                  * It would be easy to do, but doesn't seem to be necessary,
 596                  * patching the OPD symbol is enough.
 597                  */
 598                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 599                                      patch->fix_name);
 600 #ifdef CONFIG_PPC64
 601                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 602                                      patch->fix_name);
 603 #endif /* CONFIG_PPC64 */
 604         }
 605
 606         return 0;
 607 }
 608
 609
 610 static __init int vdso_setup(void)
 611 {
 612         struct lib32_elfinfo    v32;
 613         struct lib64_elfinfo    v64;
 614
 615         v32.hdr = vdso32_kbase;
 616 #ifdef CONFIG_PPC64
 617         v64.hdr = vdso64_kbase;
 618 #endif
 619         if (vdso_do_find_sections(&v32, &v64))
 620                 return -1;
 621
 622         if (vdso_fixup_datapage(&v32, &v64))
 623                 return -1;
 624
 625         if (vdso_fixup_alt_funcs(&v32, &v64))
 626                 return -1;
 627
 628         vdso_setup_trampolines(&v32, &v64);
 629
 630         return 0;
 631 }
 632
 633 /*
 634  * Called from setup_arch to initialize the bitmap of available
 635  * syscalls in the systemcfg page
 636  */
 637 static void __init vdso_setup_syscall_map(void)
 638 {
 639         unsigned int i;
 640         extern unsigned long *sys_call_table;
 641         extern unsigned long sys_ni_syscall;
 642
 643
 644         for (i = 0; i < __NR_syscalls; i++) {
 645 #ifdef CONFIG_PPC64
 646                 if (sys_call_table[i*2] != sys_ni_syscall)
 647                         vdso_data->syscall_map_64[i >> 5] |=
 648                                 0x80000000UL >> (i & 0x1f);
 649                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 650                         vdso_data->syscall_map_32[i >> 5] |=
 651                                 0x80000000UL >> (i & 0x1f);
 652 #else /* CONFIG_PPC64 */
 653                 if (sys_call_table[i] != sys_ni_syscall)
 654                         vdso_data->syscall_map_32[i >> 5] |=
 655                                 0x80000000UL >> (i & 0x1f);
 656 #endif /* CONFIG_PPC64 */
 657         }
 658 }
 659
 660
 661 void __init vdso_init(void)
 662 {
 663         int i;
 664
 665 #ifdef CONFIG_PPC64
 666         /*
 667          * Fill up the "systemcfg" stuff for backward compatiblity
 668          */
 669         strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 670         vdso_data->version.major = SYSTEMCFG_MAJOR;
 671         vdso_data->version.minor = SYSTEMCFG_MINOR;
 672         vdso_data->processor = mfspr(SPRN_PVR);
 673         /*
 674          * Fake the old platform number for pSeries and iSeries and add
 675          * in LPAR bit if necessary
 676          */
 677         vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
 678         if (firmware_has_feature(FW_FEATURE_LPAR))
 679                 vdso_data->platform |= 1;
 680         vdso_data->physicalMemorySize = lmb_phys_mem_size();
 681         vdso_data->dcache_size = ppc64_caches.dsize;
 682         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 683         vdso_data->icache_size = ppc64_caches.isize;
 684         vdso_data->icache_line_size = ppc64_caches.iline_size;
 685
 686         /*
 687          * Calculate the size of the 64 bits vDSO
 688          */
 689         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 690         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 691 #endif /* CONFIG_PPC64 */
 692
 693
 694         /*
 695          * Calculate the size of the 32 bits vDSO
 696          */
 697         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 698         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 699
 700
 701         /*
 702          * Setup the syscall map in the vDOS
 703          */
 704         vdso_setup_syscall_map();
 705         /*
 706          * Initialize the vDSO images in memory, that is do necessary
 707          * fixups of vDSO symbols, locate trampolines, etc...
 708          */
 709         if (vdso_setup()) {
 710                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 711                 vdso32_pages = 0;
 712 #ifdef CONFIG_PPC64
 713                 vdso64_pages = 0;
 714 #endif
 715                 return;
 716         }
 717
 718         /* Make sure pages are in the correct state */
 719         for (i = 0; i < vdso32_pages; i++) {
 720                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 721                 ClearPageReserved(pg);
 722                 get_page(pg);
 723
 724         }
 725 #ifdef CONFIG_PPC64
 726         for (i = 0; i < vdso64_pages; i++) {
 727                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 728                 ClearPageReserved(pg);
 729                 get_page(pg);
 730         }
 731 #endif /* CONFIG_PPC64 */
 732
 733         get_page(virt_to_page(vdso_data));
 734 }
 735
 736 int in_gate_area_no_task(unsigned long addr)
 737 {
 738         return 0;
 739 }
 740
 741 int in_gate_area(struct task_struct *task, unsigned long addr)
 742 {
 743         return 0;
 744 }
 745
 746 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 747 {
 748         return NULL;
 749 }
 750