kernel/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/pgtable.h>
  26 #include <asm/processor.h>
  27 #include <asm/mmu.h>
  28 #include <asm/mmu_context.h>
  29 #include <asm/prom.h>
  30 #include <asm/machdep.h>
  31 #include <asm/cputable.h>
  32 #include <asm/sections.h>
  33 #include <asm/firmware.h>
  34 #include <asm/vdso.h>
  35 #include <asm/vdso_datapage.h>
  36 #include <asm/setup.h>
  37
  38 #undef DEBUG
  39
  40 #ifdef DEBUG
  41 #define DBG(fmt...) printk(fmt)
  42 #else
  43 #define DBG(fmt...)
  44 #endif
  45
  46 /* Max supported size for symbol names */
  47 #define MAX_SYMNAME     64
  48
  49 /* The alignment of the vDSO */
  50 #define VDSO_ALIGNMENT  (1 << 16)
  51
  52 static unsigned int vdso32_pages;
  53 static void *vdso32_kbase;
  54 static struct page **vdso32_pagelist;
  55 unsigned long vdso32_sigtramp;
  56 unsigned long vdso32_rt_sigtramp;
  57
  58 #ifdef CONFIG_VDSO32
  59 extern char vdso32_start, vdso32_end;
  60 #endif
  61
  62 #ifdef CONFIG_PPC64
  63 extern char vdso64_start, vdso64_end;
  64 static void *vdso64_kbase = &vdso64_start;
  65 static unsigned int vdso64_pages;
  66 static struct page **vdso64_pagelist;
  67 unsigned long vdso64_rt_sigtramp;
  68 #endif /* CONFIG_PPC64 */
  69
  70 static int vdso_ready;
  71
  72 /*
  73  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  74  * Once the early boot kernel code no longer needs to muck around
  75  * with it, it will become dynamically allocated
  76  */
  77 static union {
  78         struct vdso_data        data;
  79         u8                      page[PAGE_SIZE];
  80 } vdso_data_store __page_aligned_data;
  81 struct vdso_data *vdso_data = &vdso_data_store.data;
  82
  83 /* Format of the patch table */
  84 struct vdso_patch_def
  85 {
  86         unsigned long   ftr_mask, ftr_value;
  87         const char      *gen_name;
  88         const char      *fix_name;
  89 };
  90
  91 /* Table of functions to patch based on the CPU type/revision
  92  *
  93  * Currently, we only change sync_dicache to do nothing on processors
  94  * with a coherent icache
  95  */
  96 static struct vdso_patch_def vdso_patches[] = {
  97         {
  98                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  99                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
 100         },
 101         {
 102                 CPU_FTR_USE_TB, 0,
 103                 "__kernel_gettimeofday", NULL
 104         },
 105         {
 106                 CPU_FTR_USE_TB, 0,
 107                 "__kernel_clock_gettime", NULL
 108         },
 109         {
 110                 CPU_FTR_USE_TB, 0,
 111                 "__kernel_clock_getres", NULL
 112         },
 113         {
 114                 CPU_FTR_USE_TB, 0,
 115                 "__kernel_get_tbfreq", NULL
 116         },
 117         {
 118                 CPU_FTR_USE_TB, 0,
 119                 "__kernel_time", NULL
 120         },
 121 };
 122
 123 /*
 124  * Some infos carried around for each of them during parsing at
 125  * boot time.
 126  */
 127 struct lib32_elfinfo
 128 {
 129         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 130         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 131         unsigned long   dynsymsize;     /* size of .dynsym section */
 132         char            *dynstr;        /* ptr to .dynstr section */
 133         unsigned long   text;           /* offset of .text section in .so */
 134 };
 135
 136 struct lib64_elfinfo
 137 {
 138         Elf64_Ehdr      *hdr;
 139         Elf64_Sym       *dynsym;
 140         unsigned long   dynsymsize;
 141         char            *dynstr;
 142         unsigned long   text;
 143 };
 144
 145
 146 /*
 147  * This is called from binfmt_elf, we create the special vma for the
 148  * vDSO and insert it into the mm struct tree
 149  */
 150 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 151 {
 152         struct mm_struct *mm = current->mm;
 153         struct page **vdso_pagelist;
 154         unsigned long vdso_pages;
 155         unsigned long vdso_base;
 156         int rc;
 157
 158         if (!vdso_ready)
 159                 return 0;
 160
 161 #ifdef CONFIG_PPC64
 162         if (is_32bit_task()) {
 163                 vdso_pagelist = vdso32_pagelist;
 164                 vdso_pages = vdso32_pages;
 165                 vdso_base = VDSO32_MBASE;
 166         } else {
 167                 vdso_pagelist = vdso64_pagelist;
 168                 vdso_pages = vdso64_pages;
 169                 /*
 170                  * On 64bit we don't have a preferred map address. This
 171                  * allows get_unmapped_area to find an area near other mmaps
 172                  * and most likely share a SLB entry.
 173                  */
 174                 vdso_base = 0;
 175         }
 176 #else
 177         vdso_pagelist = vdso32_pagelist;
 178         vdso_pages = vdso32_pages;
 179         vdso_base = VDSO32_MBASE;
 180 #endif
 181
 182         current->mm->context.vdso_base = 0;
 183
 184         /* vDSO has a problem and was disabled, just don't "enable" it for the
 185          * process
 186          */
 187         if (vdso_pages == 0)
 188                 return 0;
 189         /* Add a page to the vdso size for the data page */
 190         vdso_pages ++;
 191
 192         /*
 193          * pick a base address for the vDSO in process space. We try to put it
 194          * at vdso_base which is the "natural" base for it, but we might fail
 195          * and end up putting it elsewhere.
 196          * Add enough to the size so that the result can be aligned.
 197          */
 198         down_write(&mm->mmap_sem);
 199         vdso_base = get_unmapped_area(NULL, vdso_base,
 200                                       (vdso_pages << PAGE_SHIFT) +
 201                                       ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 202                                       0, 0);
 203         if (IS_ERR_VALUE(vdso_base)) {
 204                 rc = vdso_base;
 205                 goto fail_mmapsem;
 206         }
 207
 208         /* Add required alignment. */
 209         vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
 210
 211         /*
 212          * Put vDSO base into mm struct. We need to do this before calling
 213          * install_special_mapping or the perf counter mmap tracking code
 214          * will fail to recognise it as a vDSO (since arch_vma_name fails).
 215          */
 216         current->mm->context.vdso_base = vdso_base;
 217
 218         /*
 219          * our vma flags don't have VM_WRITE so by default, the process isn't
 220          * allowed to write those pages.
 221          * gdb can break that with ptrace interface, and thus trigger COW on
 222          * those pages but it's then your responsibility to never do that on
 223          * the "data" page of the vDSO or you'll stop getting kernel updates
 224          * and your nice userland gettimeofday will be totally dead.
 225          * It's fine to use that for setting breakpoints in the vDSO code
 226          * pages though.
 227          */
 228         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 229                                      VM_READ|VM_EXEC|
 230                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
 231                                      vdso_pagelist);
 232         if (rc) {
 233                 current->mm->context.vdso_base = 0;
 234                 goto fail_mmapsem;
 235         }
 236
 237         up_write(&mm->mmap_sem);
 238         return 0;
 239
 240  fail_mmapsem:
 241         up_write(&mm->mmap_sem);
 242         return rc;
 243 }
 244
 245 const char *arch_vma_name(struct vm_area_struct *vma)
 246 {
 247         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 248                 return "[vdso]";
 249         return NULL;
 250 }
 251
 252
 253
 254 #ifdef CONFIG_VDSO32
 255 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 256                                   unsigned long *size)
 257 {
 258         Elf32_Shdr *sechdrs;
 259         unsigned int i;
 260         char *secnames;
 261
 262         /* Grab section headers and strings so we can tell who is who */
 263         sechdrs = (void *)ehdr + ehdr->e_shoff;
 264         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 265
 266         /* Find the section they want */
 267         for (i = 1; i < ehdr->e_shnum; i++) {
 268                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 269                         if (size)
 270                                 *size = sechdrs[i].sh_size;
 271                         return (void *)ehdr + sechdrs[i].sh_offset;
 272                 }
 273         }
 274         *size = 0;
 275         return NULL;
 276 }
 277
 278 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 279                                         const char *symname)
 280 {
 281         unsigned int i;
 282         char name[MAX_SYMNAME], *c;
 283
 284         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 285                 if (lib->dynsym[i].st_name == 0)
 286                         continue;
 287                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 288                         MAX_SYMNAME);
 289                 c = strchr(name, '@');
 290                 if (c)
 291                         *c = 0;
 292                 if (strcmp(symname, name) == 0)
 293                         return &lib->dynsym[i];
 294         }
 295         return NULL;
 296 }
 297
 298 /* Note that we assume the section is .text and the symbol is relative to
 299  * the library base
 300  */
 301 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 302                                             const char *symname)
 303 {
 304         Elf32_Sym *sym = find_symbol32(lib, symname);
 305
 306         if (sym == NULL) {
 307                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 308                        symname);
 309                 return 0;
 310         }
 311         return sym->st_value - VDSO32_LBASE;
 312 }
 313
 314 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 315                                        struct lib64_elfinfo *v64,
 316                                        const char *orig, const char *fix)
 317 {
 318         Elf32_Sym *sym32_gen, *sym32_fix;
 319
 320         sym32_gen = find_symbol32(v32, orig);
 321         if (sym32_gen == NULL) {
 322                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 323                 return -1;
 324         }
 325         if (fix == NULL) {
 326                 sym32_gen->st_name = 0;
 327                 return 0;
 328         }
 329         sym32_fix = find_symbol32(v32, fix);
 330         if (sym32_fix == NULL) {
 331                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 332                 return -1;
 333         }
 334         sym32_gen->st_value = sym32_fix->st_value;
 335         sym32_gen->st_size = sym32_fix->st_size;
 336         sym32_gen->st_info = sym32_fix->st_info;
 337         sym32_gen->st_other = sym32_fix->st_other;
 338         sym32_gen->st_shndx = sym32_fix->st_shndx;
 339
 340         return 0;
 341 }
 342 #else /* !CONFIG_VDSO32 */
 343 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 344                                             const char *symname)
 345 {
 346         return 0;
 347 }
 348
 349 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 350                                        struct lib64_elfinfo *v64,
 351                                        const char *orig, const char *fix)
 352 {
 353         return 0;
 354 }
 355 #endif /* CONFIG_VDSO32 */
 356
 357
 358 #ifdef CONFIG_PPC64
 359
 360 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 361                                   unsigned long *size)
 362 {
 363         Elf64_Shdr *sechdrs;
 364         unsigned int i;
 365         char *secnames;
 366
 367         /* Grab section headers and strings so we can tell who is who */
 368         sechdrs = (void *)ehdr + ehdr->e_shoff;
 369         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 370
 371         /* Find the section they want */
 372         for (i = 1; i < ehdr->e_shnum; i++) {
 373                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 374                         if (size)
 375                                 *size = sechdrs[i].sh_size;
 376                         return (void *)ehdr + sechdrs[i].sh_offset;
 377                 }
 378         }
 379         if (size)
 380                 *size = 0;
 381         return NULL;
 382 }
 383
 384 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 385                                         const char *symname)
 386 {
 387         unsigned int i;
 388         char name[MAX_SYMNAME], *c;
 389
 390         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 391                 if (lib->dynsym[i].st_name == 0)
 392                         continue;
 393                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 394                         MAX_SYMNAME);
 395                 c = strchr(name, '@');
 396                 if (c)
 397                         *c = 0;
 398                 if (strcmp(symname, name) == 0)
 399                         return &lib->dynsym[i];
 400         }
 401         return NULL;
 402 }
 403
 404 /* Note that we assume the section is .text and the symbol is relative to
 405  * the library base
 406  */
 407 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 408                                             const char *symname)
 409 {
 410         Elf64_Sym *sym = find_symbol64(lib, symname);
 411
 412         if (sym == NULL) {
 413                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 414                        symname);
 415                 return 0;
 416         }
 417 #ifdef VDS64_HAS_DESCRIPTORS
 418         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 419                 VDSO64_LBASE;
 420 #else
 421         return sym->st_value - VDSO64_LBASE;
 422 #endif
 423 }
 424
 425 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 426                                        struct lib64_elfinfo *v64,
 427                                        const char *orig, const char *fix)
 428 {
 429         Elf64_Sym *sym64_gen, *sym64_fix;
 430
 431         sym64_gen = find_symbol64(v64, orig);
 432         if (sym64_gen == NULL) {
 433                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 434                 return -1;
 435         }
 436         if (fix == NULL) {
 437                 sym64_gen->st_name = 0;
 438                 return 0;
 439         }
 440         sym64_fix = find_symbol64(v64, fix);
 441         if (sym64_fix == NULL) {
 442                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 443                 return -1;
 444         }
 445         sym64_gen->st_value = sym64_fix->st_value;
 446         sym64_gen->st_size = sym64_fix->st_size;
 447         sym64_gen->st_info = sym64_fix->st_info;
 448         sym64_gen->st_other = sym64_fix->st_other;
 449         sym64_gen->st_shndx = sym64_fix->st_shndx;
 450
 451         return 0;
 452 }
 453
 454 #endif /* CONFIG_PPC64 */
 455
 456
 457 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 458                                         struct lib64_elfinfo *v64)
 459 {
 460         void *sect;
 461
 462         /*
 463          * Locate symbol tables & text section
 464          */
 465
 466 #ifdef CONFIG_VDSO32
 467         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 468         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 469         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 470                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 471                 return -1;
 472         }
 473         sect = find_section32(v32->hdr, ".text", NULL);
 474         if (sect == NULL) {
 475                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 476                 return -1;
 477         }
 478         v32->text = sect - vdso32_kbase;
 479 #endif
 480
 481 #ifdef CONFIG_PPC64
 482         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 483         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 484         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 485                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 486                 return -1;
 487         }
 488         sect = find_section64(v64->hdr, ".text", NULL);
 489         if (sect == NULL) {
 490                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 491                 return -1;
 492         }
 493         v64->text = sect - vdso64_kbase;
 494 #endif /* CONFIG_PPC64 */
 495
 496         return 0;
 497 }
 498
 499 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 500                                           struct lib64_elfinfo *v64)
 501 {
 502         /*
 503          * Find signal trampolines
 504          */
 505
 506 #ifdef CONFIG_PPC64
 507         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 508 #endif
 509         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 510         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 511 }
 512
 513 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 514                                        struct lib64_elfinfo *v64)
 515 {
 516 #ifdef CONFIG_VDSO32
 517         Elf32_Sym *sym32;
 518 #endif
 519 #ifdef CONFIG_PPC64
 520         Elf64_Sym *sym64;
 521
 522         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 523         if (sym64 == NULL) {
 524                 printk(KERN_ERR "vDSO64: Can't find symbol "
 525                        "__kernel_datapage_offset !\n");
 526                 return -1;
 527         }
 528         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 529                 (vdso64_pages << PAGE_SHIFT) -
 530                 (sym64->st_value - VDSO64_LBASE);
 531 #endif /* CONFIG_PPC64 */
 532
 533 #ifdef CONFIG_VDSO32
 534         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 535         if (sym32 == NULL) {
 536                 printk(KERN_ERR "vDSO32: Can't find symbol "
 537                        "__kernel_datapage_offset !\n");
 538                 return -1;
 539         }
 540         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 541                 (vdso32_pages << PAGE_SHIFT) -
 542                 (sym32->st_value - VDSO32_LBASE);
 543 #endif
 544
 545         return 0;
 546 }
 547
 548
 549 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 550                                       struct lib64_elfinfo *v64)
 551 {
 552         unsigned long size;
 553         void *start;
 554
 555 #ifdef CONFIG_PPC64
 556         start = find_section64(v64->hdr, "__ftr_fixup", &size);
 557         if (start)
 558                 do_feature_fixups(cur_cpu_spec->cpu_features,
 559                                   start, start + size);
 560
 561         start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
 562         if (start)
 563                 do_feature_fixups(cur_cpu_spec->mmu_features,
 564                                   start, start + size);
 565
 566         start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
 567         if (start)
 568                 do_feature_fixups(powerpc_firmware_features,
 569                                   start, start + size);
 570
 571         start = find_section64(v64->hdr, "__lwsync_fixup", &size);
 572         if (start)
 573                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 574                                  start, start + size);
 575 #endif /* CONFIG_PPC64 */
 576
 577 #ifdef CONFIG_VDSO32
 578         start = find_section32(v32->hdr, "__ftr_fixup", &size);
 579         if (start)
 580                 do_feature_fixups(cur_cpu_spec->cpu_features,
 581                                   start, start + size);
 582
 583         start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
 584         if (start)
 585                 do_feature_fixups(cur_cpu_spec->mmu_features,
 586                                   start, start + size);
 587
 588 #ifdef CONFIG_PPC64
 589         start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
 590         if (start)
 591                 do_feature_fixups(powerpc_firmware_features,
 592                                   start, start + size);
 593 #endif /* CONFIG_PPC64 */
 594
 595         start = find_section32(v32->hdr, "__lwsync_fixup", &size);
 596         if (start)
 597                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 598                                  start, start + size);
 599 #endif
 600
 601         return 0;
 602 }
 603
 604 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 605                                        struct lib64_elfinfo *v64)
 606 {
 607         int i;
 608
 609         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 610                 struct vdso_patch_def *patch = &vdso_patches[i];
 611                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 612                         == patch->ftr_value;
 613                 if (!match)
 614                         continue;
 615
 616                 DBG("replacing %s with %s...\n", patch->gen_name,
 617                     patch->fix_name ? "NONE" : patch->fix_name);
 618
 619                 /*
 620                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 621                  * patch the "." symbol on 64 bits.
 622                  * It would be easy to do, but doesn't seem to be necessary,
 623                  * patching the OPD symbol is enough.
 624                  */
 625                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 626                                      patch->fix_name);
 627 #ifdef CONFIG_PPC64
 628                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 629                                      patch->fix_name);
 630 #endif /* CONFIG_PPC64 */
 631         }
 632
 633         return 0;
 634 }
 635
 636
 637 static __init int vdso_setup(void)
 638 {
 639         struct lib32_elfinfo    v32;
 640         struct lib64_elfinfo    v64;
 641
 642         v32.hdr = vdso32_kbase;
 643 #ifdef CONFIG_PPC64
 644         v64.hdr = vdso64_kbase;
 645 #endif
 646         if (vdso_do_find_sections(&v32, &v64))
 647                 return -1;
 648
 649         if (vdso_fixup_datapage(&v32, &v64))
 650                 return -1;
 651
 652         if (vdso_fixup_features(&v32, &v64))
 653                 return -1;
 654
 655         if (vdso_fixup_alt_funcs(&v32, &v64))
 656                 return -1;
 657
 658         vdso_setup_trampolines(&v32, &v64);
 659
 660         return 0;
 661 }
 662
 663 /*
 664  * Called from setup_arch to initialize the bitmap of available
 665  * syscalls in the systemcfg page
 666  */
 667 static void __init vdso_setup_syscall_map(void)
 668 {
 669         unsigned int i;
 670         extern unsigned long *sys_call_table;
 671         extern unsigned long sys_ni_syscall;
 672
 673
 674         for (i = 0; i < __NR_syscalls; i++) {
 675 #ifdef CONFIG_PPC64
 676                 if (sys_call_table[i*2] != sys_ni_syscall)
 677                         vdso_data->syscall_map_64[i >> 5] |=
 678                                 0x80000000UL >> (i & 0x1f);
 679                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 680                         vdso_data->syscall_map_32[i >> 5] |=
 681                                 0x80000000UL >> (i & 0x1f);
 682 #else /* CONFIG_PPC64 */
 683                 if (sys_call_table[i] != sys_ni_syscall)
 684                         vdso_data->syscall_map_32[i >> 5] |=
 685                                 0x80000000UL >> (i & 0x1f);
 686 #endif /* CONFIG_PPC64 */
 687         }
 688 }
 689
 690 #ifdef CONFIG_PPC64
 691 int vdso_getcpu_init(void)
 692 {
 693         unsigned long cpu, node, val;
 694
 695         /*
 696          * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
 697          * in the next 16 bits.  The VDSO uses this to implement getcpu().
 698          */
 699         cpu = get_cpu();
 700         WARN_ON_ONCE(cpu > 0xffff);
 701
 702         node = cpu_to_node(cpu);
 703         WARN_ON_ONCE(node > 0xffff);
 704
 705         val = (cpu & 0xfff) | ((node & 0xffff) << 16);
 706         mtspr(SPRN_SPRG_VDSO_WRITE, val);
 707         get_paca()->sprg_vdso = val;
 708
 709         put_cpu();
 710
 711         return 0;
 712 }
 713 /* We need to call this before SMP init */
 714 early_initcall(vdso_getcpu_init);
 715 #endif
 716
 717 static int __init vdso_init(void)
 718 {
 719         int i;
 720
 721 #ifdef CONFIG_PPC64
 722         /*
 723          * Fill up the "systemcfg" stuff for backward compatibility
 724          */
 725         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 726         vdso_data->version.major = SYSTEMCFG_MAJOR;
 727         vdso_data->version.minor = SYSTEMCFG_MINOR;
 728         vdso_data->processor = mfspr(SPRN_PVR);
 729         /*
 730          * Fake the old platform number for pSeries and add
 731          * in LPAR bit if necessary
 732          */
 733         vdso_data->platform = 0x100;
 734         if (firmware_has_feature(FW_FEATURE_LPAR))
 735                 vdso_data->platform |= 1;
 736         vdso_data->physicalMemorySize = memblock_phys_mem_size();
 737         vdso_data->dcache_size = ppc64_caches.dsize;
 738         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 739         vdso_data->icache_size = ppc64_caches.isize;
 740         vdso_data->icache_line_size = ppc64_caches.iline_size;
 741
 742         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
 743         vdso_data->dcache_block_size = ppc64_caches.dline_size;
 744         vdso_data->icache_block_size = ppc64_caches.iline_size;
 745         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
 746         vdso_data->icache_log_block_size = ppc64_caches.log_iline_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);