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/errno.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/smp.h>
  17 #include <linux/stddef.h>
  18 #include <linux/unistd.h>
  19 #include <linux/slab.h>
  20 #include <linux/user.h>
  21 #include <linux/elf.h>
  22 #include <linux/security.h>
  23 #include <linux/memblock.h>
  24
  25 #include <asm/cpu_has_feature.h>
  26 #include <asm/pgtable.h>
  27 #include <asm/processor.h>
  28 #include <asm/mmu.h>
  29 #include <asm/mmu_context.h>
  30 #include <asm/prom.h>
  31 #include <asm/machdep.h>
  32 #include <asm/cputable.h>
  33 #include <asm/sections.h>
  34 #include <asm/firmware.h>
  35 #include <asm/vdso.h>
  36 #include <asm/vdso_datapage.h>
  37 #include <asm/setup.h>
  38
  39 #undef DEBUG
  40
  41 #ifdef DEBUG
  42 #define DBG(fmt...) printk(fmt)
  43 #else
  44 #define DBG(fmt...)
  45 #endif
  46
  47 /* Max supported size for symbol names */
  48 #define MAX_SYMNAME     64
  49
  50 /* The alignment of the vDSO */
  51 #define VDSO_ALIGNMENT  (1 << 16)
  52
  53 static unsigned int vdso32_pages;
  54 static void *vdso32_kbase;
  55 static struct page **vdso32_pagelist;
  56 unsigned long vdso32_sigtramp;
  57 unsigned long vdso32_rt_sigtramp;
  58
  59 #ifdef CONFIG_VDSO32
  60 extern char vdso32_start, vdso32_end;
  61 #endif
  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                 CPU_FTR_USE_TB, 0,
 120                 "__kernel_time", NULL
 121         },
 122 };
 123
 124 /*
 125  * Some infos carried around for each of them during parsing at
 126  * boot time.
 127  */
 128 struct lib32_elfinfo
 129 {
 130         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 131         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 132         unsigned long   dynsymsize;     /* size of .dynsym section */
 133         char            *dynstr;        /* ptr to .dynstr section */
 134         unsigned long   text;           /* offset of .text section in .so */
 135 };
 136
 137 struct lib64_elfinfo
 138 {
 139         Elf64_Ehdr      *hdr;
 140         Elf64_Sym       *dynsym;
 141         unsigned long   dynsymsize;
 142         char            *dynstr;
 143         unsigned long   text;
 144 };
 145
 146
 147 /*
 148  * This is called from binfmt_elf, we create the special vma for the
 149  * vDSO and insert it into the mm struct tree
 150  */
 151 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 152 {
 153         struct mm_struct *mm = current->mm;
 154         struct page **vdso_pagelist;
 155         unsigned long vdso_pages;
 156         unsigned long vdso_base;
 157         int rc;
 158
 159         if (!vdso_ready)
 160                 return 0;
 161
 162 #ifdef CONFIG_PPC64
 163         if (is_32bit_task()) {
 164                 vdso_pagelist = vdso32_pagelist;
 165                 vdso_pages = vdso32_pages;
 166                 vdso_base = VDSO32_MBASE;
 167         } else {
 168                 vdso_pagelist = vdso64_pagelist;
 169                 vdso_pages = vdso64_pages;
 170                 /*
 171                  * On 64bit we don't have a preferred map address. This
 172                  * allows get_unmapped_area to find an area near other mmaps
 173                  * and most likely share a SLB entry.
 174                  */
 175                 vdso_base = 0;
 176         }
 177 #else
 178         vdso_pagelist = vdso32_pagelist;
 179         vdso_pages = vdso32_pages;
 180         vdso_base = VDSO32_MBASE;
 181 #endif
 182
 183         current->mm->context.vdso_base = 0;
 184
 185         /* vDSO has a problem and was disabled, just don't "enable" it for the
 186          * process
 187          */
 188         if (vdso_pages == 0)
 189                 return 0;
 190         /* Add a page to the vdso size for the data page */
 191         vdso_pages ++;
 192
 193         /*
 194          * pick a base address for the vDSO in process space. We try to put it
 195          * at vdso_base which is the "natural" base for it, but we might fail
 196          * and end up putting it elsewhere.
 197          * Add enough to the size so that the result can be aligned.
 198          */
 199         if (down_write_killable(&mm->mmap_sem))
 200                 return -EINTR;
 201         vdso_base = get_unmapped_area(NULL, vdso_base,
 202                                       (vdso_pages << PAGE_SHIFT) +
 203                                       ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 204                                       0, 0);
 205         if (IS_ERR_VALUE(vdso_base)) {
 206                 rc = vdso_base;
 207                 goto fail_mmapsem;
 208         }
 209
 210         /* Add required alignment. */
 211         vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
 212
 213         /*
 214          * Put vDSO base into mm struct. We need to do this before calling
 215          * install_special_mapping or the perf counter mmap tracking code
 216          * will fail to recognise it as a vDSO (since arch_vma_name fails).
 217          */
 218         current->mm->context.vdso_base = vdso_base;
 219
 220         /*
 221          * our vma flags don't have VM_WRITE so by default, the process isn't
 222          * allowed to write those pages.
 223          * gdb can break that with ptrace interface, and thus trigger COW on
 224          * those pages but it's then your responsibility to never do that on
 225          * the "data" page of the vDSO or you'll stop getting kernel updates
 226          * and your nice userland gettimeofday will be totally dead.
 227          * It's fine to use that for setting breakpoints in the vDSO code
 228          * pages though.
 229          */
 230         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 231                                      VM_READ|VM_EXEC|
 232                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
 233                                      vdso_pagelist);
 234         if (rc) {
 235                 current->mm->context.vdso_base = 0;
 236                 goto fail_mmapsem;
 237         }
 238
 239         up_write(&mm->mmap_sem);
 240         return 0;
 241
 242  fail_mmapsem:
 243         up_write(&mm->mmap_sem);
 244         return rc;
 245 }
 246
 247 const char *arch_vma_name(struct vm_area_struct *vma)
 248 {
 249         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 250                 return "[vdso]";
 251         return NULL;
 252 }
 253
 254
 255
 256 #ifdef CONFIG_VDSO32
 257 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 258                                   unsigned long *size)
 259 {
 260         Elf32_Shdr *sechdrs;
 261         unsigned int i;
 262         char *secnames;
 263
 264         /* Grab section headers and strings so we can tell who is who */
 265         sechdrs = (void *)ehdr + ehdr->e_shoff;
 266         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 267
 268         /* Find the section they want */
 269         for (i = 1; i < ehdr->e_shnum; i++) {
 270                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 271                         if (size)
 272                                 *size = sechdrs[i].sh_size;
 273                         return (void *)ehdr + sechdrs[i].sh_offset;
 274                 }
 275         }
 276         *size = 0;
 277         return NULL;
 278 }
 279
 280 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 281                                         const char *symname)
 282 {
 283         unsigned int i;
 284         char name[MAX_SYMNAME], *c;
 285
 286         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 287                 if (lib->dynsym[i].st_name == 0)
 288                         continue;
 289                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 290                         MAX_SYMNAME);
 291                 c = strchr(name, '@');
 292                 if (c)
 293                         *c = 0;
 294                 if (strcmp(symname, name) == 0)
 295                         return &lib->dynsym[i];
 296         }
 297         return NULL;
 298 }
 299
 300 /* Note that we assume the section is .text and the symbol is relative to
 301  * the library base
 302  */
 303 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 304                                             const char *symname)
 305 {
 306         Elf32_Sym *sym = find_symbol32(lib, symname);
 307
 308         if (sym == NULL) {
 309                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 310                        symname);
 311                 return 0;
 312         }
 313         return sym->st_value - VDSO32_LBASE;
 314 }
 315
 316 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 317                                        struct lib64_elfinfo *v64,
 318                                        const char *orig, const char *fix)
 319 {
 320         Elf32_Sym *sym32_gen, *sym32_fix;
 321
 322         sym32_gen = find_symbol32(v32, orig);
 323         if (sym32_gen == NULL) {
 324                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 325                 return -1;
 326         }
 327         if (fix == NULL) {
 328                 sym32_gen->st_name = 0;
 329                 return 0;
 330         }
 331         sym32_fix = find_symbol32(v32, fix);
 332         if (sym32_fix == NULL) {
 333                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 334                 return -1;
 335         }
 336         sym32_gen->st_value = sym32_fix->st_value;
 337         sym32_gen->st_size = sym32_fix->st_size;
 338         sym32_gen->st_info = sym32_fix->st_info;
 339         sym32_gen->st_other = sym32_fix->st_other;
 340         sym32_gen->st_shndx = sym32_fix->st_shndx;
 341
 342         return 0;
 343 }
 344 #else /* !CONFIG_VDSO32 */
 345 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 346                                             const char *symname)
 347 {
 348         return 0;
 349 }
 350
 351 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 352                                        struct lib64_elfinfo *v64,
 353                                        const char *orig, const char *fix)
 354 {
 355         return 0;
 356 }
 357 #endif /* CONFIG_VDSO32 */
 358
 359
 360 #ifdef CONFIG_PPC64
 361
 362 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 363                                   unsigned long *size)
 364 {
 365         Elf64_Shdr *sechdrs;
 366         unsigned int i;
 367         char *secnames;
 368
 369         /* Grab section headers and strings so we can tell who is who */
 370         sechdrs = (void *)ehdr + ehdr->e_shoff;
 371         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 372
 373         /* Find the section they want */
 374         for (i = 1; i < ehdr->e_shnum; i++) {
 375                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 376                         if (size)
 377                                 *size = sechdrs[i].sh_size;
 378                         return (void *)ehdr + sechdrs[i].sh_offset;
 379                 }
 380         }
 381         if (size)
 382                 *size = 0;
 383         return NULL;
 384 }
 385
 386 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 387                                         const char *symname)
 388 {
 389         unsigned int i;
 390         char name[MAX_SYMNAME], *c;
 391
 392         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 393                 if (lib->dynsym[i].st_name == 0)
 394                         continue;
 395                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 396                         MAX_SYMNAME);
 397                 c = strchr(name, '@');
 398                 if (c)
 399                         *c = 0;
 400                 if (strcmp(symname, name) == 0)
 401                         return &lib->dynsym[i];
 402         }
 403         return NULL;
 404 }
 405
 406 /* Note that we assume the section is .text and the symbol is relative to
 407  * the library base
 408  */
 409 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 410                                             const char *symname)
 411 {
 412         Elf64_Sym *sym = find_symbol64(lib, symname);
 413
 414         if (sym == NULL) {
 415                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 416                        symname);
 417                 return 0;
 418         }
 419 #ifdef VDS64_HAS_DESCRIPTORS
 420         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 421                 VDSO64_LBASE;
 422 #else
 423         return sym->st_value - VDSO64_LBASE;
 424 #endif
 425 }
 426
 427 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 428                                        struct lib64_elfinfo *v64,
 429                                        const char *orig, const char *fix)
 430 {
 431         Elf64_Sym *sym64_gen, *sym64_fix;
 432
 433         sym64_gen = find_symbol64(v64, orig);
 434         if (sym64_gen == NULL) {
 435                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 436                 return -1;
 437         }
 438         if (fix == NULL) {
 439                 sym64_gen->st_name = 0;
 440                 return 0;
 441         }
 442         sym64_fix = find_symbol64(v64, fix);
 443         if (sym64_fix == NULL) {
 444                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 445                 return -1;
 446         }
 447         sym64_gen->st_value = sym64_fix->st_value;
 448         sym64_gen->st_size = sym64_fix->st_size;
 449         sym64_gen->st_info = sym64_fix->st_info;
 450         sym64_gen->st_other = sym64_fix->st_other;
 451         sym64_gen->st_shndx = sym64_fix->st_shndx;
 452
 453         return 0;
 454 }
 455
 456 #endif /* CONFIG_PPC64 */
 457
 458
 459 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 460                                         struct lib64_elfinfo *v64)
 461 {
 462         void *sect;
 463
 464         /*
 465          * Locate symbol tables & text section
 466          */
 467
 468 #ifdef CONFIG_VDSO32
 469         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 470         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 471         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 472                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 473                 return -1;
 474         }
 475         sect = find_section32(v32->hdr, ".text", NULL);
 476         if (sect == NULL) {
 477                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 478                 return -1;
 479         }
 480         v32->text = sect - vdso32_kbase;
 481 #endif
 482
 483 #ifdef CONFIG_PPC64
 484         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 485         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 486         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 487                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 488                 return -1;
 489         }
 490         sect = find_section64(v64->hdr, ".text", NULL);
 491         if (sect == NULL) {
 492                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 493                 return -1;
 494         }
 495         v64->text = sect - vdso64_kbase;
 496 #endif /* CONFIG_PPC64 */
 497
 498         return 0;
 499 }
 500
 501 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 502                                           struct lib64_elfinfo *v64)
 503 {
 504         /*
 505          * Find signal trampolines
 506          */
 507
 508 #ifdef CONFIG_PPC64
 509         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 510 #endif
 511         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 512         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 513 }
 514
 515 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 516                                        struct lib64_elfinfo *v64)
 517 {
 518 #ifdef CONFIG_VDSO32
 519         Elf32_Sym *sym32;
 520 #endif
 521 #ifdef CONFIG_PPC64
 522         Elf64_Sym *sym64;
 523
 524         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 525         if (sym64 == NULL) {
 526                 printk(KERN_ERR "vDSO64: Can't find symbol "
 527                        "__kernel_datapage_offset !\n");
 528                 return -1;
 529         }
 530         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 531                 (vdso64_pages << PAGE_SHIFT) -
 532                 (sym64->st_value - VDSO64_LBASE);
 533 #endif /* CONFIG_PPC64 */
 534
 535 #ifdef CONFIG_VDSO32
 536         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 537         if (sym32 == NULL) {
 538                 printk(KERN_ERR "vDSO32: Can't find symbol "
 539                        "__kernel_datapage_offset !\n");
 540                 return -1;
 541         }
 542         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 543                 (vdso32_pages << PAGE_SHIFT) -
 544                 (sym32->st_value - VDSO32_LBASE);
 545 #endif
 546
 547         return 0;
 548 }
 549
 550
 551 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 552                                       struct lib64_elfinfo *v64)
 553 {
 554         unsigned long size;
 555         void *start;
 556
 557 #ifdef CONFIG_PPC64
 558         start = find_section64(v64->hdr, "__ftr_fixup", &size);
 559         if (start)
 560                 do_feature_fixups(cur_cpu_spec->cpu_features,
 561                                   start, start + size);
 562
 563         start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
 564         if (start)
 565                 do_feature_fixups(cur_cpu_spec->mmu_features,
 566                                   start, start + size);
 567
 568         start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
 569         if (start)
 570                 do_feature_fixups(powerpc_firmware_features,
 571                                   start, start + size);
 572
 573         start = find_section64(v64->hdr, "__lwsync_fixup", &size);
 574         if (start)
 575                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 576                                  start, start + size);
 577 #endif /* CONFIG_PPC64 */
 578
 579 #ifdef CONFIG_VDSO32
 580         start = find_section32(v32->hdr, "__ftr_fixup", &size);
 581         if (start)
 582                 do_feature_fixups(cur_cpu_spec->cpu_features,
 583                                   start, start + size);
 584
 585         start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
 586         if (start)
 587                 do_feature_fixups(cur_cpu_spec->mmu_features,
 588                                   start, start + size);
 589
 590 #ifdef CONFIG_PPC64
 591         start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
 592         if (start)
 593                 do_feature_fixups(powerpc_firmware_features,
 594                                   start, start + size);
 595 #endif /* CONFIG_PPC64 */
 596
 597         start = find_section32(v32->hdr, "__lwsync_fixup", &size);
 598         if (start)
 599                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 600                                  start, start + size);
 601 #endif
 602
 603         return 0;
 604 }
 605
 606 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 607                                        struct lib64_elfinfo *v64)
 608 {
 609         int i;
 610
 611         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 612                 struct vdso_patch_def *patch = &vdso_patches[i];
 613                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 614                         == patch->ftr_value;
 615                 if (!match)
 616                         continue;
 617
 618                 DBG("replacing %s with %s...\n", patch->gen_name,
 619                     patch->fix_name ? "NONE" : patch->fix_name);
 620
 621                 /*
 622                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 623                  * patch the "." symbol on 64 bits.
 624                  * It would be easy to do, but doesn't seem to be necessary,
 625                  * patching the OPD symbol is enough.
 626                  */
 627                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 628                                      patch->fix_name);
 629 #ifdef CONFIG_PPC64
 630                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 631                                      patch->fix_name);
 632 #endif /* CONFIG_PPC64 */
 633         }
 634
 635         return 0;
 636 }
 637
 638
 639 static __init int vdso_setup(void)
 640 {
 641         struct lib32_elfinfo    v32;
 642         struct lib64_elfinfo    v64;
 643
 644         v32.hdr = vdso32_kbase;
 645 #ifdef CONFIG_PPC64
 646         v64.hdr = vdso64_kbase;
 647 #endif
 648         if (vdso_do_find_sections(&v32, &v64))
 649                 return -1;
 650
 651         if (vdso_fixup_datapage(&v32, &v64))
 652                 return -1;
 653
 654         if (vdso_fixup_features(&v32, &v64))
 655                 return -1;
 656
 657         if (vdso_fixup_alt_funcs(&v32, &v64))
 658                 return -1;
 659
 660         vdso_setup_trampolines(&v32, &v64);
 661
 662         return 0;
 663 }
 664
 665 /*
 666  * Called from setup_arch to initialize the bitmap of available
 667  * syscalls in the systemcfg page
 668  */
 669 static void __init vdso_setup_syscall_map(void)
 670 {
 671         unsigned int i;
 672         extern unsigned long *sys_call_table;
 673         extern unsigned long sys_ni_syscall;
 674
 675
 676         for (i = 0; i < NR_syscalls; i++) {
 677 #ifdef CONFIG_PPC64
 678                 if (sys_call_table[i*2] != sys_ni_syscall)
 679                         vdso_data->syscall_map_64[i >> 5] |=
 680                                 0x80000000UL >> (i & 0x1f);
 681                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 682                         vdso_data->syscall_map_32[i >> 5] |=
 683                                 0x80000000UL >> (i & 0x1f);
 684 #else /* CONFIG_PPC64 */
 685                 if (sys_call_table[i] != sys_ni_syscall)
 686                         vdso_data->syscall_map_32[i >> 5] |=
 687                                 0x80000000UL >> (i & 0x1f);
 688 #endif /* CONFIG_PPC64 */
 689         }
 690 }
 691
 692 #ifdef CONFIG_PPC64
 693 int vdso_getcpu_init(void)
 694 {
 695         unsigned long cpu, node, val;
 696
 697         /*
 698          * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
 699          * in the next 16 bits.  The VDSO uses this to implement getcpu().
 700          */
 701         cpu = get_cpu();
 702         WARN_ON_ONCE(cpu > 0xffff);
 703
 704         node = cpu_to_node(cpu);
 705         WARN_ON_ONCE(node > 0xffff);
 706
 707         val = (cpu & 0xfff) | ((node & 0xffff) << 16);
 708         mtspr(SPRN_SPRG_VDSO_WRITE, val);
 709         get_paca()->sprg_vdso = val;
 710
 711         put_cpu();
 712
 713         return 0;
 714 }
 715 /* We need to call this before SMP init */
 716 early_initcall(vdso_getcpu_init);
 717 #endif
 718
 719 static int __init vdso_init(void)
 720 {
 721         int i;
 722
 723 #ifdef CONFIG_PPC64
 724         /*
 725          * Fill up the "systemcfg" stuff for backward compatibility
 726          */
 727         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 728         vdso_data->version.major = SYSTEMCFG_MAJOR;
 729         vdso_data->version.minor = SYSTEMCFG_MINOR;
 730         vdso_data->processor = mfspr(SPRN_PVR);
 731         /*
 732          * Fake the old platform number for pSeries and add
 733          * in LPAR bit if necessary
 734          */
 735         vdso_data->platform = 0x100;
 736         if (firmware_has_feature(FW_FEATURE_LPAR))
 737                 vdso_data->platform |= 1;
 738         vdso_data->physicalMemorySize = memblock_phys_mem_size();
 739         vdso_data->dcache_size = ppc64_caches.l1d.size;
 740         vdso_data->dcache_line_size = ppc64_caches.l1d.line_size;
 741         vdso_data->icache_size = ppc64_caches.l1i.size;
 742         vdso_data->icache_line_size = ppc64_caches.l1i.line_size;
 743         vdso_data->dcache_block_size = ppc64_caches.l1d.block_size;
 744         vdso_data->icache_block_size = ppc64_caches.l1i.block_size;
 745         vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
 746         vdso_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
 747
 748         /*
 749          * Calculate the size of the 64 bits vDSO
 750          */
 751         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 752         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 753 #else
 754         vdso_data->dcache_block_size = L1_CACHE_BYTES;
 755         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
 756         vdso_data->icache_block_size = L1_CACHE_BYTES;
 757         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
 758 #endif /* CONFIG_PPC64 */
 759
 760
 761 #ifdef CONFIG_VDSO32
 762         vdso32_kbase = &vdso32_start;
 763
 764         /*
 765          * Calculate the size of the 32 bits vDSO
 766          */
 767         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 768         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 769 #endif
 770
 771
 772         /*
 773          * Setup the syscall map in the vDOS
 774          */
 775         vdso_setup_syscall_map();
 776
 777         /*
 778          * Initialize the vDSO images in memory, that is do necessary
 779          * fixups of vDSO symbols, locate trampolines, etc...
 780          */
 781         if (vdso_setup()) {
 782                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 783                 vdso32_pages = 0;
 784 #ifdef CONFIG_PPC64
 785                 vdso64_pages = 0;
 786 #endif
 787                 return 0;
 788         }
 789
 790 #ifdef CONFIG_VDSO32
 791         /* Make sure pages are in the correct state */
 792         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 793                                   GFP_KERNEL);
 794         BUG_ON(vdso32_pagelist == NULL);
 795         for (i = 0; i < vdso32_pages; i++) {
 796                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 797                 ClearPageReserved(pg);
 798                 get_page(pg);
 799                 vdso32_pagelist[i] = pg;
 800         }
 801         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 802         vdso32_pagelist[i] = NULL;
 803 #endif
 804
 805 #ifdef CONFIG_PPC64
 806         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 807                                   GFP_KERNEL);
 808         BUG_ON(vdso64_pagelist == NULL);
 809         for (i = 0; i < vdso64_pages; i++) {
 810                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 811                 ClearPageReserved(pg);
 812                 get_page(pg);
 813                 vdso64_pagelist[i] = pg;
 814         }
 815         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 816         vdso64_pagelist[i] = NULL;
 817 #endif /* CONFIG_PPC64 */
 818
 819         get_page(virt_to_page(vdso_data));
 820
 821         smp_wmb();
 822         vdso_ready = 1;
 823
 824         return 0;
 825 }
 826 arch_initcall(vdso_init);