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 extern char vdso32_start, vdso32_end;
  53 static void *vdso32_kbase = &vdso32_start;
  54 static unsigned int vdso32_pages;
  55 static struct page **vdso32_pagelist;
  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 static unsigned int vdso64_pages;
  63 static struct page **vdso64_pagelist;
  64 unsigned long vdso64_rt_sigtramp;
  65 #endif /* CONFIG_PPC64 */
  66
  67 static int vdso_ready;
  68
  69 /*
  70  * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
  71  * Once the early boot kernel code no longer needs to muck around
  72  * with it, it will become dynamically allocated
  73  */
  74 static union {
  75         struct vdso_data        data;
  76         u8                      page[PAGE_SIZE];
  77 } vdso_data_store __page_aligned_data;
  78 struct vdso_data *vdso_data = &vdso_data_store.data;
  79
  80 /* Format of the patch table */
  81 struct vdso_patch_def
  82 {
  83         unsigned long   ftr_mask, ftr_value;
  84         const char      *gen_name;
  85         const char      *fix_name;
  86 };
  87
  88 /* Table of functions to patch based on the CPU type/revision
  89  *
  90  * Currently, we only change sync_dicache to do nothing on processors
  91  * with a coherent icache
  92  */
  93 static struct vdso_patch_def vdso_patches[] = {
  94         {
  95                 CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
  96                 "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
  97         },
  98         {
  99                 CPU_FTR_USE_TB, 0,
 100                 "__kernel_gettimeofday", NULL
 101         },
 102         {
 103                 CPU_FTR_USE_TB, 0,
 104                 "__kernel_clock_gettime", NULL
 105         },
 106         {
 107                 CPU_FTR_USE_TB, 0,
 108                 "__kernel_clock_getres", NULL
 109         },
 110         {
 111                 CPU_FTR_USE_TB, 0,
 112                 "__kernel_get_tbfreq", NULL
 113         },
 114         {
 115                 CPU_FTR_USE_TB, 0,
 116                 "__kernel_time", NULL
 117         },
 118 };
 119
 120 /*
 121  * Some infos carried around for each of them during parsing at
 122  * boot time.
 123  */
 124 struct lib32_elfinfo
 125 {
 126         Elf32_Ehdr      *hdr;           /* ptr to ELF */
 127         Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
 128         unsigned long   dynsymsize;     /* size of .dynsym section */
 129         char            *dynstr;        /* ptr to .dynstr section */
 130         unsigned long   text;           /* offset of .text section in .so */
 131 };
 132
 133 struct lib64_elfinfo
 134 {
 135         Elf64_Ehdr      *hdr;
 136         Elf64_Sym       *dynsym;
 137         unsigned long   dynsymsize;
 138         char            *dynstr;
 139         unsigned long   text;
 140 };
 141
 142
 143 #ifdef __DEBUG
 144 static void dump_one_vdso_page(struct page *pg, struct page *upg)
 145 {
 146         printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
 147                page_count(pg),
 148                pg->flags);
 149         if (upg && !IS_ERR(upg) /* && pg != upg*/) {
 150                 printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
 151                                                        << PAGE_SHIFT),
 152                        page_count(upg),
 153                        upg->flags);
 154         }
 155         printk("\n");
 156 }
 157
 158 static void dump_vdso_pages(struct vm_area_struct * vma)
 159 {
 160         int i;
 161
 162         if (!vma || is_32bit_task()) {
 163                 printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
 164                 for (i=0; i<vdso32_pages; i++) {
 165                         struct page *pg = virt_to_page(vdso32_kbase +
 166                                                        i*PAGE_SIZE);
 167                         struct page *upg = (vma && vma->vm_mm) ?
 168                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 169                                 : NULL;
 170                         dump_one_vdso_page(pg, upg);
 171                 }
 172         }
 173         if (!vma || !is_32bit_task()) {
 174                 printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
 175                 for (i=0; i<vdso64_pages; i++) {
 176                         struct page *pg = virt_to_page(vdso64_kbase +
 177                                                        i*PAGE_SIZE);
 178                         struct page *upg = (vma && vma->vm_mm) ?
 179                                 follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
 180                                 : NULL;
 181                         dump_one_vdso_page(pg, upg);
 182                 }
 183         }
 184 }
 185 #endif /* DEBUG */
 186
 187 /*
 188  * This is called from binfmt_elf, we create the special vma for the
 189  * vDSO and insert it into the mm struct tree
 190  */
 191 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 192 {
 193         struct mm_struct *mm = current->mm;
 194         struct page **vdso_pagelist;
 195         unsigned long vdso_pages;
 196         unsigned long vdso_base;
 197         int rc;
 198
 199         if (!vdso_ready)
 200                 return 0;
 201
 202 #ifdef CONFIG_PPC64
 203         if (is_32bit_task()) {
 204                 vdso_pagelist = vdso32_pagelist;
 205                 vdso_pages = vdso32_pages;
 206                 vdso_base = VDSO32_MBASE;
 207         } else {
 208                 vdso_pagelist = vdso64_pagelist;
 209                 vdso_pages = vdso64_pages;
 210                 /*
 211                  * On 64bit we don't have a preferred map address. This
 212                  * allows get_unmapped_area to find an area near other mmaps
 213                  * and most likely share a SLB entry.
 214                  */
 215                 vdso_base = 0;
 216         }
 217 #else
 218         vdso_pagelist = vdso32_pagelist;
 219         vdso_pages = vdso32_pages;
 220         vdso_base = VDSO32_MBASE;
 221 #endif
 222
 223         current->mm->context.vdso_base = 0;
 224
 225         /* vDSO has a problem and was disabled, just don't "enable" it for the
 226          * process
 227          */
 228         if (vdso_pages == 0)
 229                 return 0;
 230         /* Add a page to the vdso size for the data page */
 231         vdso_pages ++;
 232
 233         /*
 234          * pick a base address for the vDSO in process space. We try to put it
 235          * at vdso_base which is the "natural" base for it, but we might fail
 236          * and end up putting it elsewhere.
 237          * Add enough to the size so that the result can be aligned.
 238          */
 239         down_write(&mm->mmap_sem);
 240         vdso_base = get_unmapped_area(NULL, vdso_base,
 241                                       (vdso_pages << PAGE_SHIFT) +
 242                                       ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 243                                       0, 0);
 244         if (IS_ERR_VALUE(vdso_base)) {
 245                 rc = vdso_base;
 246                 goto fail_mmapsem;
 247         }
 248
 249         /* Add required alignment. */
 250         vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
 251
 252         /*
 253          * Put vDSO base into mm struct. We need to do this before calling
 254          * install_special_mapping or the perf counter mmap tracking code
 255          * will fail to recognise it as a vDSO (since arch_vma_name fails).
 256          */
 257         current->mm->context.vdso_base = vdso_base;
 258
 259         /*
 260          * our vma flags don't have VM_WRITE so by default, the process isn't
 261          * allowed to write those pages.
 262          * gdb can break that with ptrace interface, and thus trigger COW on
 263          * those pages but it's then your responsibility to never do that on
 264          * the "data" page of the vDSO or you'll stop getting kernel updates
 265          * and your nice userland gettimeofday will be totally dead.
 266          * It's fine to use that for setting breakpoints in the vDSO code
 267          * pages though.
 268          */
 269         rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 270                                      VM_READ|VM_EXEC|
 271                                      VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
 272                                      vdso_pagelist);
 273         if (rc) {
 274                 current->mm->context.vdso_base = 0;
 275                 goto fail_mmapsem;
 276         }
 277
 278         up_write(&mm->mmap_sem);
 279         return 0;
 280
 281  fail_mmapsem:
 282         up_write(&mm->mmap_sem);
 283         return rc;
 284 }
 285
 286 const char *arch_vma_name(struct vm_area_struct *vma)
 287 {
 288         if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
 289                 return "[vdso]";
 290         return NULL;
 291 }
 292
 293
 294
 295 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 296                                   unsigned long *size)
 297 {
 298         Elf32_Shdr *sechdrs;
 299         unsigned int i;
 300         char *secnames;
 301
 302         /* Grab section headers and strings so we can tell who is who */
 303         sechdrs = (void *)ehdr + ehdr->e_shoff;
 304         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 305
 306         /* Find the section they want */
 307         for (i = 1; i < ehdr->e_shnum; i++) {
 308                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 309                         if (size)
 310                                 *size = sechdrs[i].sh_size;
 311                         return (void *)ehdr + sechdrs[i].sh_offset;
 312                 }
 313         }
 314         *size = 0;
 315         return NULL;
 316 }
 317
 318 static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
 319                                         const char *symname)
 320 {
 321         unsigned int i;
 322         char name[MAX_SYMNAME], *c;
 323
 324         for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
 325                 if (lib->dynsym[i].st_name == 0)
 326                         continue;
 327                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 328                         MAX_SYMNAME);
 329                 c = strchr(name, '@');
 330                 if (c)
 331                         *c = 0;
 332                 if (strcmp(symname, name) == 0)
 333                         return &lib->dynsym[i];
 334         }
 335         return NULL;
 336 }
 337
 338 /* Note that we assume the section is .text and the symbol is relative to
 339  * the library base
 340  */
 341 static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 342                                             const char *symname)
 343 {
 344         Elf32_Sym *sym = find_symbol32(lib, symname);
 345
 346         if (sym == NULL) {
 347                 printk(KERN_WARNING "vDSO32: function %s not found !\n",
 348                        symname);
 349                 return 0;
 350         }
 351         return sym->st_value - VDSO32_LBASE;
 352 }
 353
 354 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
 355                                        struct lib64_elfinfo *v64,
 356                                        const char *orig, const char *fix)
 357 {
 358         Elf32_Sym *sym32_gen, *sym32_fix;
 359
 360         sym32_gen = find_symbol32(v32, orig);
 361         if (sym32_gen == NULL) {
 362                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
 363                 return -1;
 364         }
 365         if (fix == NULL) {
 366                 sym32_gen->st_name = 0;
 367                 return 0;
 368         }
 369         sym32_fix = find_symbol32(v32, fix);
 370         if (sym32_fix == NULL) {
 371                 printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
 372                 return -1;
 373         }
 374         sym32_gen->st_value = sym32_fix->st_value;
 375         sym32_gen->st_size = sym32_fix->st_size;
 376         sym32_gen->st_info = sym32_fix->st_info;
 377         sym32_gen->st_other = sym32_fix->st_other;
 378         sym32_gen->st_shndx = sym32_fix->st_shndx;
 379
 380         return 0;
 381 }
 382
 383
 384 #ifdef CONFIG_PPC64
 385
 386 static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
 387                                   unsigned long *size)
 388 {
 389         Elf64_Shdr *sechdrs;
 390         unsigned int i;
 391         char *secnames;
 392
 393         /* Grab section headers and strings so we can tell who is who */
 394         sechdrs = (void *)ehdr + ehdr->e_shoff;
 395         secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
 396
 397         /* Find the section they want */
 398         for (i = 1; i < ehdr->e_shnum; i++) {
 399                 if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
 400                         if (size)
 401                                 *size = sechdrs[i].sh_size;
 402                         return (void *)ehdr + sechdrs[i].sh_offset;
 403                 }
 404         }
 405         if (size)
 406                 *size = 0;
 407         return NULL;
 408 }
 409
 410 static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
 411                                         const char *symname)
 412 {
 413         unsigned int i;
 414         char name[MAX_SYMNAME], *c;
 415
 416         for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
 417                 if (lib->dynsym[i].st_name == 0)
 418                         continue;
 419                 strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
 420                         MAX_SYMNAME);
 421                 c = strchr(name, '@');
 422                 if (c)
 423                         *c = 0;
 424                 if (strcmp(symname, name) == 0)
 425                         return &lib->dynsym[i];
 426         }
 427         return NULL;
 428 }
 429
 430 /* Note that we assume the section is .text and the symbol is relative to
 431  * the library base
 432  */
 433 static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 434                                             const char *symname)
 435 {
 436         Elf64_Sym *sym = find_symbol64(lib, symname);
 437
 438         if (sym == NULL) {
 439                 printk(KERN_WARNING "vDSO64: function %s not found !\n",
 440                        symname);
 441                 return 0;
 442         }
 443 #ifdef VDS64_HAS_DESCRIPTORS
 444         return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
 445                 VDSO64_LBASE;
 446 #else
 447         return sym->st_value - VDSO64_LBASE;
 448 #endif
 449 }
 450
 451 static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
 452                                        struct lib64_elfinfo *v64,
 453                                        const char *orig, const char *fix)
 454 {
 455         Elf64_Sym *sym64_gen, *sym64_fix;
 456
 457         sym64_gen = find_symbol64(v64, orig);
 458         if (sym64_gen == NULL) {
 459                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
 460                 return -1;
 461         }
 462         if (fix == NULL) {
 463                 sym64_gen->st_name = 0;
 464                 return 0;
 465         }
 466         sym64_fix = find_symbol64(v64, fix);
 467         if (sym64_fix == NULL) {
 468                 printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
 469                 return -1;
 470         }
 471         sym64_gen->st_value = sym64_fix->st_value;
 472         sym64_gen->st_size = sym64_fix->st_size;
 473         sym64_gen->st_info = sym64_fix->st_info;
 474         sym64_gen->st_other = sym64_fix->st_other;
 475         sym64_gen->st_shndx = sym64_fix->st_shndx;
 476
 477         return 0;
 478 }
 479
 480 #endif /* CONFIG_PPC64 */
 481
 482
 483 static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
 484                                         struct lib64_elfinfo *v64)
 485 {
 486         void *sect;
 487
 488         /*
 489          * Locate symbol tables & text section
 490          */
 491
 492         v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
 493         v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
 494         if (v32->dynsym == NULL || v32->dynstr == NULL) {
 495                 printk(KERN_ERR "vDSO32: required symbol section not found\n");
 496                 return -1;
 497         }
 498         sect = find_section32(v32->hdr, ".text", NULL);
 499         if (sect == NULL) {
 500                 printk(KERN_ERR "vDSO32: the .text section was not found\n");
 501                 return -1;
 502         }
 503         v32->text = sect - vdso32_kbase;
 504
 505 #ifdef CONFIG_PPC64
 506         v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
 507         v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
 508         if (v64->dynsym == NULL || v64->dynstr == NULL) {
 509                 printk(KERN_ERR "vDSO64: required symbol section not found\n");
 510                 return -1;
 511         }
 512         sect = find_section64(v64->hdr, ".text", NULL);
 513         if (sect == NULL) {
 514                 printk(KERN_ERR "vDSO64: the .text section was not found\n");
 515                 return -1;
 516         }
 517         v64->text = sect - vdso64_kbase;
 518 #endif /* CONFIG_PPC64 */
 519
 520         return 0;
 521 }
 522
 523 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 524                                           struct lib64_elfinfo *v64)
 525 {
 526         /*
 527          * Find signal trampolines
 528          */
 529
 530 #ifdef CONFIG_PPC64
 531         vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 532 #endif
 533         vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
 534         vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 535 }
 536
 537 static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 538                                        struct lib64_elfinfo *v64)
 539 {
 540         Elf32_Sym *sym32;
 541 #ifdef CONFIG_PPC64
 542         Elf64_Sym *sym64;
 543
 544         sym64 = find_symbol64(v64, "__kernel_datapage_offset");
 545         if (sym64 == NULL) {
 546                 printk(KERN_ERR "vDSO64: Can't find symbol "
 547                        "__kernel_datapage_offset !\n");
 548                 return -1;
 549         }
 550         *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
 551                 (vdso64_pages << PAGE_SHIFT) -
 552                 (sym64->st_value - VDSO64_LBASE);
 553 #endif /* CONFIG_PPC64 */
 554
 555         sym32 = find_symbol32(v32, "__kernel_datapage_offset");
 556         if (sym32 == NULL) {
 557                 printk(KERN_ERR "vDSO32: Can't find symbol "
 558                        "__kernel_datapage_offset !\n");
 559                 return -1;
 560         }
 561         *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
 562                 (vdso32_pages << PAGE_SHIFT) -
 563                 (sym32->st_value - VDSO32_LBASE);
 564
 565         return 0;
 566 }
 567
 568
 569 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 570                                       struct lib64_elfinfo *v64)
 571 {
 572         void *start32;
 573         unsigned long size32;
 574
 575 #ifdef CONFIG_PPC64
 576         void *start64;
 577         unsigned long size64;
 578
 579         start64 = find_section64(v64->hdr, "__ftr_fixup", &size64);
 580         if (start64)
 581                 do_feature_fixups(cur_cpu_spec->cpu_features,
 582                                   start64, start64 + size64);
 583
 584         start64 = find_section64(v64->hdr, "__mmu_ftr_fixup", &size64);
 585         if (start64)
 586                 do_feature_fixups(cur_cpu_spec->mmu_features,
 587                                   start64, start64 + size64);
 588
 589         start64 = find_section64(v64->hdr, "__fw_ftr_fixup", &size64);
 590         if (start64)
 591                 do_feature_fixups(powerpc_firmware_features,
 592                                   start64, start64 + size64);
 593
 594         start64 = find_section64(v64->hdr, "__lwsync_fixup", &size64);
 595         if (start64)
 596                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 597                                  start64, start64 + size64);
 598 #endif /* CONFIG_PPC64 */
 599
 600         start32 = find_section32(v32->hdr, "__ftr_fixup", &size32);
 601         if (start32)
 602                 do_feature_fixups(cur_cpu_spec->cpu_features,
 603                                   start32, start32 + size32);
 604
 605         start32 = find_section32(v32->hdr, "__mmu_ftr_fixup", &size32);
 606         if (start32)
 607                 do_feature_fixups(cur_cpu_spec->mmu_features,
 608                                   start32, start32 + size32);
 609
 610 #ifdef CONFIG_PPC64
 611         start32 = find_section32(v32->hdr, "__fw_ftr_fixup", &size32);
 612         if (start32)
 613                 do_feature_fixups(powerpc_firmware_features,
 614                                   start32, start32 + size32);
 615 #endif /* CONFIG_PPC64 */
 616
 617         start32 = find_section32(v32->hdr, "__lwsync_fixup", &size32);
 618         if (start32)
 619                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
 620                                  start32, start32 + size32);
 621
 622         return 0;
 623 }
 624
 625 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 626                                        struct lib64_elfinfo *v64)
 627 {
 628         int i;
 629
 630         for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
 631                 struct vdso_patch_def *patch = &vdso_patches[i];
 632                 int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
 633                         == patch->ftr_value;
 634                 if (!match)
 635                         continue;
 636
 637                 DBG("replacing %s with %s...\n", patch->gen_name,
 638                     patch->fix_name ? "NONE" : patch->fix_name);
 639
 640                 /*
 641                  * Patch the 32 bits and 64 bits symbols. Note that we do not
 642                  * patch the "." symbol on 64 bits.
 643                  * It would be easy to do, but doesn't seem to be necessary,
 644                  * patching the OPD symbol is enough.
 645                  */
 646                 vdso_do_func_patch32(v32, v64, patch->gen_name,
 647                                      patch->fix_name);
 648 #ifdef CONFIG_PPC64
 649                 vdso_do_func_patch64(v32, v64, patch->gen_name,
 650                                      patch->fix_name);
 651 #endif /* CONFIG_PPC64 */
 652         }
 653
 654         return 0;
 655 }
 656
 657
 658 static __init int vdso_setup(void)
 659 {
 660         struct lib32_elfinfo    v32;
 661         struct lib64_elfinfo    v64;
 662
 663         v32.hdr = vdso32_kbase;
 664 #ifdef CONFIG_PPC64
 665         v64.hdr = vdso64_kbase;
 666 #endif
 667         if (vdso_do_find_sections(&v32, &v64))
 668                 return -1;
 669
 670         if (vdso_fixup_datapage(&v32, &v64))
 671                 return -1;
 672
 673         if (vdso_fixup_features(&v32, &v64))
 674                 return -1;
 675
 676         if (vdso_fixup_alt_funcs(&v32, &v64))
 677                 return -1;
 678
 679         vdso_setup_trampolines(&v32, &v64);
 680
 681         return 0;
 682 }
 683
 684 /*
 685  * Called from setup_arch to initialize the bitmap of available
 686  * syscalls in the systemcfg page
 687  */
 688 static void __init vdso_setup_syscall_map(void)
 689 {
 690         unsigned int i;
 691         extern unsigned long *sys_call_table;
 692         extern unsigned long sys_ni_syscall;
 693
 694
 695         for (i = 0; i < __NR_syscalls; i++) {
 696 #ifdef CONFIG_PPC64
 697                 if (sys_call_table[i*2] != sys_ni_syscall)
 698                         vdso_data->syscall_map_64[i >> 5] |=
 699                                 0x80000000UL >> (i & 0x1f);
 700                 if (sys_call_table[i*2+1] != sys_ni_syscall)
 701                         vdso_data->syscall_map_32[i >> 5] |=
 702                                 0x80000000UL >> (i & 0x1f);
 703 #else /* CONFIG_PPC64 */
 704                 if (sys_call_table[i] != sys_ni_syscall)
 705                         vdso_data->syscall_map_32[i >> 5] |=
 706                                 0x80000000UL >> (i & 0x1f);
 707 #endif /* CONFIG_PPC64 */
 708         }
 709 }
 710
 711 #ifdef CONFIG_PPC64
 712 int vdso_getcpu_init(void)
 713 {
 714         unsigned long cpu, node, val;
 715
 716         /*
 717          * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
 718          * in the next 16 bits.  The VDSO uses this to implement getcpu().
 719          */
 720         cpu = get_cpu();
 721         WARN_ON_ONCE(cpu > 0xffff);
 722
 723         node = cpu_to_node(cpu);
 724         WARN_ON_ONCE(node > 0xffff);
 725
 726         val = (cpu & 0xfff) | ((node & 0xffff) << 16);
 727         mtspr(SPRN_SPRG_VDSO_WRITE, val);
 728         get_paca()->sprg_vdso = val;
 729
 730         put_cpu();
 731
 732         return 0;
 733 }
 734 /* We need to call this before SMP init */
 735 early_initcall(vdso_getcpu_init);
 736 #endif
 737
 738 static int __init vdso_init(void)
 739 {
 740         int i;
 741
 742 #ifdef CONFIG_PPC64
 743         /*
 744          * Fill up the "systemcfg" stuff for backward compatibility
 745          */
 746         strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
 747         vdso_data->version.major = SYSTEMCFG_MAJOR;
 748         vdso_data->version.minor = SYSTEMCFG_MINOR;
 749         vdso_data->processor = mfspr(SPRN_PVR);
 750         /*
 751          * Fake the old platform number for pSeries and add
 752          * in LPAR bit if necessary
 753          */
 754         vdso_data->platform = 0x100;
 755         if (firmware_has_feature(FW_FEATURE_LPAR))
 756                 vdso_data->platform |= 1;
 757         vdso_data->physicalMemorySize = memblock_phys_mem_size();
 758         vdso_data->dcache_size = ppc64_caches.dsize;
 759         vdso_data->dcache_line_size = ppc64_caches.dline_size;
 760         vdso_data->icache_size = ppc64_caches.isize;
 761         vdso_data->icache_line_size = ppc64_caches.iline_size;
 762
 763         /* XXXOJN: Blocks should be added to ppc64_caches and used instead */
 764         vdso_data->dcache_block_size = ppc64_caches.dline_size;
 765         vdso_data->icache_block_size = ppc64_caches.iline_size;
 766         vdso_data->dcache_log_block_size = ppc64_caches.log_dline_size;
 767         vdso_data->icache_log_block_size = ppc64_caches.log_iline_size;
 768
 769         /*
 770          * Calculate the size of the 64 bits vDSO
 771          */
 772         vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 773         DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
 774 #else
 775         vdso_data->dcache_block_size = L1_CACHE_BYTES;
 776         vdso_data->dcache_log_block_size = L1_CACHE_SHIFT;
 777         vdso_data->icache_block_size = L1_CACHE_BYTES;
 778         vdso_data->icache_log_block_size = L1_CACHE_SHIFT;
 779 #endif /* CONFIG_PPC64 */
 780
 781
 782         /*
 783          * Calculate the size of the 32 bits vDSO
 784          */
 785         vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 786         DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
 787
 788
 789         /*
 790          * Setup the syscall map in the vDOS
 791          */
 792         vdso_setup_syscall_map();
 793
 794         /*
 795          * Initialize the vDSO images in memory, that is do necessary
 796          * fixups of vDSO symbols, locate trampolines, etc...
 797          */
 798         if (vdso_setup()) {
 799                 printk(KERN_ERR "vDSO setup failure, not enabled !\n");
 800                 vdso32_pages = 0;
 801 #ifdef CONFIG_PPC64
 802                 vdso64_pages = 0;
 803 #endif
 804                 return 0;
 805         }
 806
 807         /* Make sure pages are in the correct state */
 808         vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
 809                                   GFP_KERNEL);
 810         BUG_ON(vdso32_pagelist == NULL);
 811         for (i = 0; i < vdso32_pages; i++) {
 812                 struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 813                 ClearPageReserved(pg);
 814                 get_page(pg);
 815                 vdso32_pagelist[i] = pg;
 816         }
 817         vdso32_pagelist[i++] = virt_to_page(vdso_data);
 818         vdso32_pagelist[i] = NULL;
 819
 820 #ifdef CONFIG_PPC64
 821         vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
 822                                   GFP_KERNEL);
 823         BUG_ON(vdso64_pagelist == NULL);
 824         for (i = 0; i < vdso64_pages; i++) {
 825                 struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 826                 ClearPageReserved(pg);
 827                 get_page(pg);
 828                 vdso64_pagelist[i] = pg;
 829         }
 830         vdso64_pagelist[i++] = virt_to_page(vdso_data);
 831         vdso64_pagelist[i] = NULL;
 832 #endif /* CONFIG_PPC64 */
 833
 834         get_page(virt_to_page(vdso_data));
 835
 836         smp_wmb();
 837         vdso_ready = 1;
 838
 839         return 0;
 840 }
 841 arch_initcall(vdso_init);