kernel/tools/perf/util/symbol.c

   1 #include <dirent.h>
   2 #include <errno.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <sys/param.h>
   9 #include <fcntl.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include "build-id.h"
  13 #include "util.h"
  14 #include "debug.h"
  15 #include "machine.h"
  16 #include "symbol.h"
  17 #include "strlist.h"
  18 #include "intlist.h"
  19 #include "header.h"
  20
  21 #include <elf.h>
  22 #include <limits.h>
  23 #include <symbol/kallsyms.h>
  24 #include <sys/utsname.h>
  25
  26 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
  27                                 symbol_filter_t filter);
  28 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
  29                         symbol_filter_t filter);
  30 int vmlinux_path__nr_entries;
  31 char **vmlinux_path;
  32
  33 struct symbol_conf symbol_conf = {
  34         .use_modules            = true,
  35         .try_vmlinux_path       = true,
  36         .annotate_src           = true,
  37         .demangle               = true,
  38         .demangle_kernel        = false,
  39         .cumulate_callchain     = true,
  40         .show_hist_headers      = true,
  41         .symfs                  = "",
  42 };
  43
  44 static enum dso_binary_type binary_type_symtab[] = {
  45         DSO_BINARY_TYPE__KALLSYMS,
  46         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  47         DSO_BINARY_TYPE__JAVA_JIT,
  48         DSO_BINARY_TYPE__DEBUGLINK,
  49         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  50         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  51         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  52         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  53         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  54         DSO_BINARY_TYPE__GUEST_KMODULE,
  55         DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  56         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  57         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  58         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  59         DSO_BINARY_TYPE__NOT_FOUND,
  60 };
  61
  62 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  63
  64 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  65 {
  66         symbol_type = toupper(symbol_type);
  67
  68         switch (map_type) {
  69         case MAP__FUNCTION:
  70                 return symbol_type == 'T' || symbol_type == 'W';
  71         case MAP__VARIABLE:
  72                 return symbol_type == 'D';
  73         default:
  74                 return false;
  75         }
  76 }
  77
  78 static int prefix_underscores_count(const char *str)
  79 {
  80         const char *tail = str;
  81
  82         while (*tail == '_')
  83                 tail++;
  84
  85         return tail - str;
  86 }
  87
  88 int __weak arch__choose_best_symbol(struct symbol *syma,
  89                                     struct symbol *symb __maybe_unused)
  90 {
  91         /* Avoid "SyS" kernel syscall aliases */
  92         if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
  93                 return SYMBOL_B;
  94         if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
  95                 return SYMBOL_B;
  96
  97         return SYMBOL_A;
  98 }
  99
 100 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 101 {
 102         s64 a;
 103         s64 b;
 104         size_t na, nb;
 105
 106         /* Prefer a symbol with non zero length */
 107         a = syma->end - syma->start;
 108         b = symb->end - symb->start;
 109         if ((b == 0) && (a > 0))
 110                 return SYMBOL_A;
 111         else if ((a == 0) && (b > 0))
 112                 return SYMBOL_B;
 113
 114         /* Prefer a non weak symbol over a weak one */
 115         a = syma->binding == STB_WEAK;
 116         b = symb->binding == STB_WEAK;
 117         if (b && !a)
 118                 return SYMBOL_A;
 119         if (a && !b)
 120                 return SYMBOL_B;
 121
 122         /* Prefer a global symbol over a non global one */
 123         a = syma->binding == STB_GLOBAL;
 124         b = symb->binding == STB_GLOBAL;
 125         if (a && !b)
 126                 return SYMBOL_A;
 127         if (b && !a)
 128                 return SYMBOL_B;
 129
 130         /* Prefer a symbol with less underscores */
 131         a = prefix_underscores_count(syma->name);
 132         b = prefix_underscores_count(symb->name);
 133         if (b > a)
 134                 return SYMBOL_A;
 135         else if (a > b)
 136                 return SYMBOL_B;
 137
 138         /* Choose the symbol with the longest name */
 139         na = strlen(syma->name);
 140         nb = strlen(symb->name);
 141         if (na > nb)
 142                 return SYMBOL_A;
 143         else if (na < nb)
 144                 return SYMBOL_B;
 145
 146         return arch__choose_best_symbol(syma, symb);
 147 }
 148
 149 void symbols__fixup_duplicate(struct rb_root *symbols)
 150 {
 151         struct rb_node *nd;
 152         struct symbol *curr, *next;
 153
 154         nd = rb_first(symbols);
 155
 156         while (nd) {
 157                 curr = rb_entry(nd, struct symbol, rb_node);
 158 again:
 159                 nd = rb_next(&curr->rb_node);
 160                 next = rb_entry(nd, struct symbol, rb_node);
 161
 162                 if (!nd)
 163                         break;
 164
 165                 if (curr->start != next->start)
 166                         continue;
 167
 168                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 169                         rb_erase(&next->rb_node, symbols);
 170                         symbol__delete(next);
 171                         goto again;
 172                 } else {
 173                         nd = rb_next(&curr->rb_node);
 174                         rb_erase(&curr->rb_node, symbols);
 175                         symbol__delete(curr);
 176                 }
 177         }
 178 }
 179
 180 void symbols__fixup_end(struct rb_root *symbols)
 181 {
 182         struct rb_node *nd, *prevnd = rb_first(symbols);
 183         struct symbol *curr, *prev;
 184
 185         if (prevnd == NULL)
 186                 return;
 187
 188         curr = rb_entry(prevnd, struct symbol, rb_node);
 189
 190         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 191                 prev = curr;
 192                 curr = rb_entry(nd, struct symbol, rb_node);
 193
 194                 if (prev->end == prev->start && prev->end != curr->start)
 195                         prev->end = curr->start;
 196         }
 197
 198         /* Last entry */
 199         if (curr->end == curr->start)
 200                 curr->end = roundup(curr->start, 4096);
 201 }
 202
 203 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 204 {
 205         struct maps *maps = &mg->maps[type];
 206         struct map *next, *curr;
 207
 208         pthread_rwlock_wrlock(&maps->lock);
 209
 210         curr = maps__first(maps);
 211         if (curr == NULL)
 212                 goto out_unlock;
 213
 214         for (next = map__next(curr); next; next = map__next(curr)) {
 215                 curr->end = next->start;
 216                 curr = next;
 217         }
 218
 219         /*
 220          * We still haven't the actual symbols, so guess the
 221          * last map final address.
 222          */
 223         curr->end = ~0ULL;
 224
 225 out_unlock:
 226         pthread_rwlock_unlock(&maps->lock);
 227 }
 228
 229 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 230 {
 231         size_t namelen = strlen(name) + 1;
 232         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 233                                         sizeof(*sym) + namelen));
 234         if (sym == NULL)
 235                 return NULL;
 236
 237         if (symbol_conf.priv_size)
 238                 sym = ((void *)sym) + symbol_conf.priv_size;
 239
 240         sym->start   = start;
 241         sym->end     = len ? start + len : start;
 242         sym->binding = binding;
 243         sym->namelen = namelen - 1;
 244
 245         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 246                   __func__, name, start, sym->end);
 247         memcpy(sym->name, name, namelen);
 248
 249         return sym;
 250 }
 251
 252 void symbol__delete(struct symbol *sym)
 253 {
 254         free(((void *)sym) - symbol_conf.priv_size);
 255 }
 256
 257 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 258 {
 259         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 260                        sym->start, sym->end,
 261                        sym->binding == STB_GLOBAL ? 'g' :
 262                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 263                        sym->name);
 264 }
 265
 266 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 267                                     const struct addr_location *al, FILE *fp)
 268 {
 269         unsigned long offset;
 270         size_t length;
 271
 272         if (sym && sym->name) {
 273                 length = fprintf(fp, "%s", sym->name);
 274                 if (al) {
 275                         if (al->addr < sym->end)
 276                                 offset = al->addr - sym->start;
 277                         else
 278                                 offset = al->addr - al->map->start - sym->start;
 279                         length += fprintf(fp, "+0x%lx", offset);
 280                 }
 281                 return length;
 282         } else
 283                 return fprintf(fp, "[unknown]");
 284 }
 285
 286 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 287 {
 288         return symbol__fprintf_symname_offs(sym, NULL, fp);
 289 }
 290
 291 void symbols__delete(struct rb_root *symbols)
 292 {
 293         struct symbol *pos;
 294         struct rb_node *next = rb_first(symbols);
 295
 296         while (next) {
 297                 pos = rb_entry(next, struct symbol, rb_node);
 298                 next = rb_next(&pos->rb_node);
 299                 rb_erase(&pos->rb_node, symbols);
 300                 symbol__delete(pos);
 301         }
 302 }
 303
 304 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 305 {
 306         struct rb_node **p = &symbols->rb_node;
 307         struct rb_node *parent = NULL;
 308         const u64 ip = sym->start;
 309         struct symbol *s;
 310
 311         while (*p != NULL) {
 312                 parent = *p;
 313                 s = rb_entry(parent, struct symbol, rb_node);
 314                 if (ip < s->start)
 315                         p = &(*p)->rb_left;
 316                 else
 317                         p = &(*p)->rb_right;
 318         }
 319         rb_link_node(&sym->rb_node, parent, p);
 320         rb_insert_color(&sym->rb_node, symbols);
 321 }
 322
 323 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 324 {
 325         struct rb_node *n;
 326
 327         if (symbols == NULL)
 328                 return NULL;
 329
 330         n = symbols->rb_node;
 331
 332         while (n) {
 333                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 334
 335                 if (ip < s->start)
 336                         n = n->rb_left;
 337                 else if (ip >= s->end)
 338                         n = n->rb_right;
 339                 else
 340                         return s;
 341         }
 342
 343         return NULL;
 344 }
 345
 346 static struct symbol *symbols__first(struct rb_root *symbols)
 347 {
 348         struct rb_node *n = rb_first(symbols);
 349
 350         if (n)
 351                 return rb_entry(n, struct symbol, rb_node);
 352
 353         return NULL;
 354 }
 355
 356 static struct symbol *symbols__next(struct symbol *sym)
 357 {
 358         struct rb_node *n = rb_next(&sym->rb_node);
 359
 360         if (n)
 361                 return rb_entry(n, struct symbol, rb_node);
 362
 363         return NULL;
 364 }
 365
 366 struct symbol_name_rb_node {
 367         struct rb_node  rb_node;
 368         struct symbol   sym;
 369 };
 370
 371 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 372 {
 373         struct rb_node **p = &symbols->rb_node;
 374         struct rb_node *parent = NULL;
 375         struct symbol_name_rb_node *symn, *s;
 376
 377         symn = container_of(sym, struct symbol_name_rb_node, sym);
 378
 379         while (*p != NULL) {
 380                 parent = *p;
 381                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 382                 if (strcmp(sym->name, s->sym.name) < 0)
 383                         p = &(*p)->rb_left;
 384                 else
 385                         p = &(*p)->rb_right;
 386         }
 387         rb_link_node(&symn->rb_node, parent, p);
 388         rb_insert_color(&symn->rb_node, symbols);
 389 }
 390
 391 static void symbols__sort_by_name(struct rb_root *symbols,
 392                                   struct rb_root *source)
 393 {
 394         struct rb_node *nd;
 395
 396         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 397                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 398                 symbols__insert_by_name(symbols, pos);
 399         }
 400 }
 401
 402 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 403                                             const char *name)
 404 {
 405         struct rb_node *n;
 406         struct symbol_name_rb_node *s = NULL;
 407
 408         if (symbols == NULL)
 409                 return NULL;
 410
 411         n = symbols->rb_node;
 412
 413         while (n) {
 414                 int cmp;
 415
 416                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 417                 cmp = arch__compare_symbol_names(name, s->sym.name);
 418
 419                 if (cmp < 0)
 420                         n = n->rb_left;
 421                 else if (cmp > 0)
 422                         n = n->rb_right;
 423                 else
 424                         break;
 425         }
 426
 427         if (n == NULL)
 428                 return NULL;
 429
 430         /* return first symbol that has same name (if any) */
 431         for (n = rb_prev(n); n; n = rb_prev(n)) {
 432                 struct symbol_name_rb_node *tmp;
 433
 434                 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
 435                 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
 436                         break;
 437
 438                 s = tmp;
 439         }
 440
 441         return &s->sym;
 442 }
 443
 444 void dso__reset_find_symbol_cache(struct dso *dso)
 445 {
 446         enum map_type type;
 447
 448         for (type = MAP__FUNCTION; type <= MAP__VARIABLE; ++type) {
 449                 dso->last_find_result[type].addr   = 0;
 450                 dso->last_find_result[type].symbol = NULL;
 451         }
 452 }
 453
 454 struct symbol *dso__find_symbol(struct dso *dso,
 455                                 enum map_type type, u64 addr)
 456 {
 457         if (dso->last_find_result[type].addr != addr) {
 458                 dso->last_find_result[type].addr   = addr;
 459                 dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr);
 460         }
 461
 462         return dso->last_find_result[type].symbol;
 463 }
 464
 465 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
 466 {
 467         return symbols__first(&dso->symbols[type]);
 468 }
 469
 470 struct symbol *dso__next_symbol(struct symbol *sym)
 471 {
 472         return symbols__next(sym);
 473 }
 474
 475 struct symbol *symbol__next_by_name(struct symbol *sym)
 476 {
 477         struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
 478         struct rb_node *n = rb_next(&s->rb_node);
 479
 480         return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
 481 }
 482
 483  /*
 484   * Teturns first symbol that matched with @name.
 485   */
 486 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 487                                         const char *name)
 488 {
 489         return symbols__find_by_name(&dso->symbol_names[type], name);
 490 }
 491
 492 void dso__sort_by_name(struct dso *dso, enum map_type type)
 493 {
 494         dso__set_sorted_by_name(dso, type);
 495         return symbols__sort_by_name(&dso->symbol_names[type],
 496                                      &dso->symbols[type]);
 497 }
 498
 499 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 500                                     enum map_type type, FILE *fp)
 501 {
 502         size_t ret = 0;
 503         struct rb_node *nd;
 504         struct symbol_name_rb_node *pos;
 505
 506         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 507                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 508                 fprintf(fp, "%s\n", pos->sym.name);
 509         }
 510
 511         return ret;
 512 }
 513
 514 int modules__parse(const char *filename, void *arg,
 515                    int (*process_module)(void *arg, const char *name,
 516                                          u64 start))
 517 {
 518         char *line = NULL;
 519         size_t n;
 520         FILE *file;
 521         int err = 0;
 522
 523         file = fopen(filename, "r");
 524         if (file == NULL)
 525                 return -1;
 526
 527         while (1) {
 528                 char name[PATH_MAX];
 529                 u64 start;
 530                 char *sep;
 531                 ssize_t line_len;
 532
 533                 line_len = getline(&line, &n, file);
 534                 if (line_len < 0) {
 535                         if (feof(file))
 536                                 break;
 537                         err = -1;
 538                         goto out;
 539                 }
 540
 541                 if (!line) {
 542                         err = -1;
 543                         goto out;
 544                 }
 545
 546                 line[--line_len] = '\0'; /* \n */
 547
 548                 sep = strrchr(line, 'x');
 549                 if (sep == NULL)
 550                         continue;
 551
 552                 hex2u64(sep + 1, &start);
 553
 554                 sep = strchr(line, ' ');
 555                 if (sep == NULL)
 556                         continue;
 557
 558                 *sep = '\0';
 559
 560                 scnprintf(name, sizeof(name), "[%s]", line);
 561
 562                 err = process_module(arg, name, start);
 563                 if (err)
 564                         break;
 565         }
 566 out:
 567         free(line);
 568         fclose(file);
 569         return err;
 570 }
 571
 572 struct process_kallsyms_args {
 573         struct map *map;
 574         struct dso *dso;
 575 };
 576
 577 /*
 578  * These are symbols in the kernel image, so make sure that
 579  * sym is from a kernel DSO.
 580  */
 581 bool symbol__is_idle(struct symbol *sym)
 582 {
 583         const char * const idle_symbols[] = {
 584                 "cpu_idle",
 585                 "cpu_startup_entry",
 586                 "intel_idle",
 587                 "default_idle",
 588                 "native_safe_halt",
 589                 "enter_idle",
 590                 "exit_idle",
 591                 "mwait_idle",
 592                 "mwait_idle_with_hints",
 593                 "poll_idle",
 594                 "ppc64_runlatch_off",
 595                 "pseries_dedicated_idle_sleep",
 596                 NULL
 597         };
 598
 599         int i;
 600
 601         if (!sym)
 602                 return false;
 603
 604         for (i = 0; idle_symbols[i]; i++) {
 605                 if (!strcmp(idle_symbols[i], sym->name))
 606                         return true;
 607         }
 608
 609         return false;
 610 }
 611
 612 static int map__process_kallsym_symbol(void *arg, const char *name,
 613                                        char type, u64 start)
 614 {
 615         struct symbol *sym;
 616         struct process_kallsyms_args *a = arg;
 617         struct rb_root *root = &a->dso->symbols[a->map->type];
 618
 619         if (!symbol_type__is_a(type, a->map->type))
 620                 return 0;
 621
 622         /*
 623          * module symbols are not sorted so we add all
 624          * symbols, setting length to 0, and rely on
 625          * symbols__fixup_end() to fix it up.
 626          */
 627         sym = symbol__new(start, 0, kallsyms2elf_binding(type), name);
 628         if (sym == NULL)
 629                 return -ENOMEM;
 630         /*
 631          * We will pass the symbols to the filter later, in
 632          * map__split_kallsyms, when we have split the maps per module
 633          */
 634         symbols__insert(root, sym);
 635
 636         return 0;
 637 }
 638
 639 /*
 640  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 641  * so that we can in the next step set the symbol ->end address and then
 642  * call kernel_maps__split_kallsyms.
 643  */
 644 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 645                                   struct map *map)
 646 {
 647         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 648         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 649 }
 650
 651 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
 652                                          symbol_filter_t filter)
 653 {
 654         struct map_groups *kmaps = map__kmaps(map);
 655         struct map *curr_map;
 656         struct symbol *pos;
 657         int count = 0;
 658         struct rb_root old_root = dso->symbols[map->type];
 659         struct rb_root *root = &dso->symbols[map->type];
 660         struct rb_node *next = rb_first(root);
 661
 662         if (!kmaps)
 663                 return -1;
 664
 665         *root = RB_ROOT;
 666
 667         while (next) {
 668                 char *module;
 669
 670                 pos = rb_entry(next, struct symbol, rb_node);
 671                 next = rb_next(&pos->rb_node);
 672
 673                 rb_erase_init(&pos->rb_node, &old_root);
 674
 675                 module = strchr(pos->name, '\t');
 676                 if (module)
 677                         *module = '\0';
 678
 679                 curr_map = map_groups__find(kmaps, map->type, pos->start);
 680
 681                 if (!curr_map || (filter && filter(curr_map, pos))) {
 682                         symbol__delete(pos);
 683                         continue;
 684                 }
 685
 686                 pos->start -= curr_map->start - curr_map->pgoff;
 687                 if (pos->end)
 688                         pos->end -= curr_map->start - curr_map->pgoff;
 689                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 690                 ++count;
 691         }
 692
 693         /* Symbols have been adjusted */
 694         dso->adjust_symbols = 1;
 695
 696         return count;
 697 }
 698
 699 /*
 700  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 701  * kernel range is broken in several maps, named [kernel].N, as we don't have
 702  * the original ELF section names vmlinux have.
 703  */
 704 static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
 705                                symbol_filter_t filter)
 706 {
 707         struct map_groups *kmaps = map__kmaps(map);
 708         struct machine *machine;
 709         struct map *curr_map = map;
 710         struct symbol *pos;
 711         int count = 0, moved = 0;
 712         struct rb_root *root = &dso->symbols[map->type];
 713         struct rb_node *next = rb_first(root);
 714         int kernel_range = 0;
 715
 716         if (!kmaps)
 717                 return -1;
 718
 719         machine = kmaps->machine;
 720
 721         while (next) {
 722                 char *module;
 723
 724                 pos = rb_entry(next, struct symbol, rb_node);
 725                 next = rb_next(&pos->rb_node);
 726
 727                 module = strchr(pos->name, '\t');
 728                 if (module) {
 729                         if (!symbol_conf.use_modules)
 730                                 goto discard_symbol;
 731
 732                         *module++ = '\0';
 733
 734                         if (strcmp(curr_map->dso->short_name, module)) {
 735                                 if (curr_map != map &&
 736                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 737                                     machine__is_default_guest(machine)) {
 738                                         /*
 739                                          * We assume all symbols of a module are
 740                                          * continuous in * kallsyms, so curr_map
 741                                          * points to a module and all its
 742                                          * symbols are in its kmap. Mark it as
 743                                          * loaded.
 744                                          */
 745                                         dso__set_loaded(curr_map->dso,
 746                                                         curr_map->type);
 747                                 }
 748
 749                                 curr_map = map_groups__find_by_name(kmaps,
 750                                                         map->type, module);
 751                                 if (curr_map == NULL) {
 752                                         pr_debug("%s/proc/{kallsyms,modules} "
 753                                                  "inconsistency while looking "
 754                                                  "for \"%s\" module!\n",
 755                                                  machine->root_dir, module);
 756                                         curr_map = map;
 757                                         goto discard_symbol;
 758                                 }
 759
 760                                 if (curr_map->dso->loaded &&
 761                                     !machine__is_default_guest(machine))
 762                                         goto discard_symbol;
 763                         }
 764                         /*
 765                          * So that we look just like we get from .ko files,
 766                          * i.e. not prelinked, relative to map->start.
 767                          */
 768                         pos->start = curr_map->map_ip(curr_map, pos->start);
 769                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 770                 } else if (curr_map != map) {
 771                         char dso_name[PATH_MAX];
 772                         struct dso *ndso;
 773
 774                         if (delta) {
 775                                 /* Kernel was relocated at boot time */
 776                                 pos->start -= delta;
 777                                 pos->end -= delta;
 778                         }
 779
 780                         if (count == 0) {
 781                                 curr_map = map;
 782                                 goto filter_symbol;
 783                         }
 784
 785                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 786                                 snprintf(dso_name, sizeof(dso_name),
 787                                         "[guest.kernel].%d",
 788                                         kernel_range++);
 789                         else
 790                                 snprintf(dso_name, sizeof(dso_name),
 791                                         "[kernel].%d",
 792                                         kernel_range++);
 793
 794                         ndso = dso__new(dso_name);
 795                         if (ndso == NULL)
 796                                 return -1;
 797
 798                         ndso->kernel = dso->kernel;
 799
 800                         curr_map = map__new2(pos->start, ndso, map->type);
 801                         if (curr_map == NULL) {
 802                                 dso__put(ndso);
 803                                 return -1;
 804                         }
 805
 806                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 807                         map_groups__insert(kmaps, curr_map);
 808                         ++kernel_range;
 809                 } else if (delta) {
 810                         /* Kernel was relocated at boot time */
 811                         pos->start -= delta;
 812                         pos->end -= delta;
 813                 }
 814 filter_symbol:
 815                 if (filter && filter(curr_map, pos)) {
 816 discard_symbol:         rb_erase(&pos->rb_node, root);
 817                         symbol__delete(pos);
 818                 } else {
 819                         if (curr_map != map) {
 820                                 rb_erase(&pos->rb_node, root);
 821                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 822                                 ++moved;
 823                         } else
 824                                 ++count;
 825                 }
 826         }
 827
 828         if (curr_map != map &&
 829             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 830             machine__is_default_guest(kmaps->machine)) {
 831                 dso__set_loaded(curr_map->dso, curr_map->type);
 832         }
 833
 834         return count + moved;
 835 }
 836
 837 bool symbol__restricted_filename(const char *filename,
 838                                  const char *restricted_filename)
 839 {
 840         bool restricted = false;
 841
 842         if (symbol_conf.kptr_restrict) {
 843                 char *r = realpath(filename, NULL);
 844
 845                 if (r != NULL) {
 846                         restricted = strcmp(r, restricted_filename) == 0;
 847                         free(r);
 848                         return restricted;
 849                 }
 850         }
 851
 852         return restricted;
 853 }
 854
 855 struct module_info {
 856         struct rb_node rb_node;
 857         char *name;
 858         u64 start;
 859 };
 860
 861 static void add_module(struct module_info *mi, struct rb_root *modules)
 862 {
 863         struct rb_node **p = &modules->rb_node;
 864         struct rb_node *parent = NULL;
 865         struct module_info *m;
 866
 867         while (*p != NULL) {
 868                 parent = *p;
 869                 m = rb_entry(parent, struct module_info, rb_node);
 870                 if (strcmp(mi->name, m->name) < 0)
 871                         p = &(*p)->rb_left;
 872                 else
 873                         p = &(*p)->rb_right;
 874         }
 875         rb_link_node(&mi->rb_node, parent, p);
 876         rb_insert_color(&mi->rb_node, modules);
 877 }
 878
 879 static void delete_modules(struct rb_root *modules)
 880 {
 881         struct module_info *mi;
 882         struct rb_node *next = rb_first(modules);
 883
 884         while (next) {
 885                 mi = rb_entry(next, struct module_info, rb_node);
 886                 next = rb_next(&mi->rb_node);
 887                 rb_erase(&mi->rb_node, modules);
 888                 zfree(&mi->name);
 889                 free(mi);
 890         }
 891 }
 892
 893 static struct module_info *find_module(const char *name,
 894                                        struct rb_root *modules)
 895 {
 896         struct rb_node *n = modules->rb_node;
 897
 898         while (n) {
 899                 struct module_info *m;
 900                 int cmp;
 901
 902                 m = rb_entry(n, struct module_info, rb_node);
 903                 cmp = strcmp(name, m->name);
 904                 if (cmp < 0)
 905                         n = n->rb_left;
 906                 else if (cmp > 0)
 907                         n = n->rb_right;
 908                 else
 909                         return m;
 910         }
 911
 912         return NULL;
 913 }
 914
 915 static int __read_proc_modules(void *arg, const char *name, u64 start)
 916 {
 917         struct rb_root *modules = arg;
 918         struct module_info *mi;
 919
 920         mi = zalloc(sizeof(struct module_info));
 921         if (!mi)
 922                 return -ENOMEM;
 923
 924         mi->name = strdup(name);
 925         mi->start = start;
 926
 927         if (!mi->name) {
 928                 free(mi);
 929                 return -ENOMEM;
 930         }
 931
 932         add_module(mi, modules);
 933
 934         return 0;
 935 }
 936
 937 static int read_proc_modules(const char *filename, struct rb_root *modules)
 938 {
 939         if (symbol__restricted_filename(filename, "/proc/modules"))
 940                 return -1;
 941
 942         if (modules__parse(filename, modules, __read_proc_modules)) {
 943                 delete_modules(modules);
 944                 return -1;
 945         }
 946
 947         return 0;
 948 }
 949
 950 int compare_proc_modules(const char *from, const char *to)
 951 {
 952         struct rb_root from_modules = RB_ROOT;
 953         struct rb_root to_modules = RB_ROOT;
 954         struct rb_node *from_node, *to_node;
 955         struct module_info *from_m, *to_m;
 956         int ret = -1;
 957
 958         if (read_proc_modules(from, &from_modules))
 959                 return -1;
 960
 961         if (read_proc_modules(to, &to_modules))
 962                 goto out_delete_from;
 963
 964         from_node = rb_first(&from_modules);
 965         to_node = rb_first(&to_modules);
 966         while (from_node) {
 967                 if (!to_node)
 968                         break;
 969
 970                 from_m = rb_entry(from_node, struct module_info, rb_node);
 971                 to_m = rb_entry(to_node, struct module_info, rb_node);
 972
 973                 if (from_m->start != to_m->start ||
 974                     strcmp(from_m->name, to_m->name))
 975                         break;
 976
 977                 from_node = rb_next(from_node);
 978                 to_node = rb_next(to_node);
 979         }
 980
 981         if (!from_node && !to_node)
 982                 ret = 0;
 983
 984         delete_modules(&to_modules);
 985 out_delete_from:
 986         delete_modules(&from_modules);
 987
 988         return ret;
 989 }
 990
 991 static int do_validate_kcore_modules(const char *filename, struct map *map,
 992                                   struct map_groups *kmaps)
 993 {
 994         struct rb_root modules = RB_ROOT;
 995         struct map *old_map;
 996         int err;
 997
 998         err = read_proc_modules(filename, &modules);
 999         if (err)
1000                 return err;
1001
1002         old_map = map_groups__first(kmaps, map->type);
1003         while (old_map) {
1004                 struct map *next = map_groups__next(old_map);
1005                 struct module_info *mi;
1006
1007                 if (old_map == map || old_map->start == map->start) {
1008                         /* The kernel map */
1009                         old_map = next;
1010                         continue;
1011                 }
1012
1013                 /* Module must be in memory at the same address */
1014                 mi = find_module(old_map->dso->short_name, &modules);
1015                 if (!mi || mi->start != old_map->start) {
1016                         err = -EINVAL;
1017                         goto out;
1018                 }
1019
1020                 old_map = next;
1021         }
1022 out:
1023         delete_modules(&modules);
1024         return err;
1025 }
1026
1027 /*
1028  * If kallsyms is referenced by name then we look for filename in the same
1029  * directory.
1030  */
1031 static bool filename_from_kallsyms_filename(char *filename,
1032                                             const char *base_name,
1033                                             const char *kallsyms_filename)
1034 {
1035         char *name;
1036
1037         strcpy(filename, kallsyms_filename);
1038         name = strrchr(filename, '/');
1039         if (!name)
1040                 return false;
1041
1042         name += 1;
1043
1044         if (!strcmp(name, "kallsyms")) {
1045                 strcpy(name, base_name);
1046                 return true;
1047         }
1048
1049         return false;
1050 }
1051
1052 static int validate_kcore_modules(const char *kallsyms_filename,
1053                                   struct map *map)
1054 {
1055         struct map_groups *kmaps = map__kmaps(map);
1056         char modules_filename[PATH_MAX];
1057
1058         if (!kmaps)
1059                 return -EINVAL;
1060
1061         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1062                                              kallsyms_filename))
1063                 return -EINVAL;
1064
1065         if (do_validate_kcore_modules(modules_filename, map, kmaps))
1066                 return -EINVAL;
1067
1068         return 0;
1069 }
1070
1071 static int validate_kcore_addresses(const char *kallsyms_filename,
1072                                     struct map *map)
1073 {
1074         struct kmap *kmap = map__kmap(map);
1075
1076         if (!kmap)
1077                 return -EINVAL;
1078
1079         if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1080                 u64 start;
1081
1082                 start = kallsyms__get_function_start(kallsyms_filename,
1083                                                      kmap->ref_reloc_sym->name);
1084                 if (start != kmap->ref_reloc_sym->addr)
1085                         return -EINVAL;
1086         }
1087
1088         return validate_kcore_modules(kallsyms_filename, map);
1089 }
1090
1091 struct kcore_mapfn_data {
1092         struct dso *dso;
1093         enum map_type type;
1094         struct list_head maps;
1095 };
1096
1097 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1098 {
1099         struct kcore_mapfn_data *md = data;
1100         struct map *map;
1101
1102         map = map__new2(start, md->dso, md->type);
1103         if (map == NULL)
1104                 return -ENOMEM;
1105
1106         map->end = map->start + len;
1107         map->pgoff = pgoff;
1108
1109         list_add(&map->node, &md->maps);
1110
1111         return 0;
1112 }
1113
1114 static int dso__load_kcore(struct dso *dso, struct map *map,
1115                            const char *kallsyms_filename)
1116 {
1117         struct map_groups *kmaps = map__kmaps(map);
1118         struct machine *machine;
1119         struct kcore_mapfn_data md;
1120         struct map *old_map, *new_map, *replacement_map = NULL;
1121         bool is_64_bit;
1122         int err, fd;
1123         char kcore_filename[PATH_MAX];
1124         struct symbol *sym;
1125
1126         if (!kmaps)
1127                 return -EINVAL;
1128
1129         machine = kmaps->machine;
1130
1131         /* This function requires that the map is the kernel map */
1132         if (map != machine->vmlinux_maps[map->type])
1133                 return -EINVAL;
1134
1135         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1136                                              kallsyms_filename))
1137                 return -EINVAL;
1138
1139         /* Modules and kernel must be present at their original addresses */
1140         if (validate_kcore_addresses(kallsyms_filename, map))
1141                 return -EINVAL;
1142
1143         md.dso = dso;
1144         md.type = map->type;
1145         INIT_LIST_HEAD(&md.maps);
1146
1147         fd = open(kcore_filename, O_RDONLY);
1148         if (fd < 0) {
1149                 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1150                          kcore_filename);
1151                 return -EINVAL;
1152         }
1153
1154         /* Read new maps into temporary lists */
1155         err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1156                               &is_64_bit);
1157         if (err)
1158                 goto out_err;
1159         dso->is_64_bit = is_64_bit;
1160
1161         if (list_empty(&md.maps)) {
1162                 err = -EINVAL;
1163                 goto out_err;
1164         }
1165
1166         /* Remove old maps */
1167         old_map = map_groups__first(kmaps, map->type);
1168         while (old_map) {
1169                 struct map *next = map_groups__next(old_map);
1170
1171                 if (old_map != map)
1172                         map_groups__remove(kmaps, old_map);
1173                 old_map = next;
1174         }
1175
1176         /* Find the kernel map using the first symbol */
1177         sym = dso__first_symbol(dso, map->type);
1178         list_for_each_entry(new_map, &md.maps, node) {
1179                 if (sym && sym->start >= new_map->start &&
1180                     sym->start < new_map->end) {
1181                         replacement_map = new_map;
1182                         break;
1183                 }
1184         }
1185
1186         if (!replacement_map)
1187                 replacement_map = list_entry(md.maps.next, struct map, node);
1188
1189         /* Add new maps */
1190         while (!list_empty(&md.maps)) {
1191                 new_map = list_entry(md.maps.next, struct map, node);
1192                 list_del_init(&new_map->node);
1193                 if (new_map == replacement_map) {
1194                         map->start      = new_map->start;
1195                         map->end        = new_map->end;
1196                         map->pgoff      = new_map->pgoff;
1197                         map->map_ip     = new_map->map_ip;
1198                         map->unmap_ip   = new_map->unmap_ip;
1199                         /* Ensure maps are correctly ordered */
1200                         map__get(map);
1201                         map_groups__remove(kmaps, map);
1202                         map_groups__insert(kmaps, map);
1203                         map__put(map);
1204                 } else {
1205                         map_groups__insert(kmaps, new_map);
1206                 }
1207
1208                 map__put(new_map);
1209         }
1210
1211         /*
1212          * Set the data type and long name so that kcore can be read via
1213          * dso__data_read_addr().
1214          */
1215         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1216                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1217         else
1218                 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1219         dso__set_long_name(dso, strdup(kcore_filename), true);
1220
1221         close(fd);
1222
1223         if (map->type == MAP__FUNCTION)
1224                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1225         else
1226                 pr_debug("Using %s for kernel data\n", kcore_filename);
1227
1228         return 0;
1229
1230 out_err:
1231         while (!list_empty(&md.maps)) {
1232                 map = list_entry(md.maps.next, struct map, node);
1233                 list_del_init(&map->node);
1234                 map__put(map);
1235         }
1236         close(fd);
1237         return -EINVAL;
1238 }
1239
1240 /*
1241  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1242  * delta based on the relocation reference symbol.
1243  */
1244 static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
1245 {
1246         struct kmap *kmap = map__kmap(map);
1247         u64 addr;
1248
1249         if (!kmap)
1250                 return -1;
1251
1252         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1253                 return 0;
1254
1255         addr = kallsyms__get_function_start(filename,
1256                                             kmap->ref_reloc_sym->name);
1257         if (!addr)
1258                 return -1;
1259
1260         *delta = addr - kmap->ref_reloc_sym->addr;
1261         return 0;
1262 }
1263
1264 int dso__load_kallsyms(struct dso *dso, const char *filename,
1265                        struct map *map, symbol_filter_t filter)
1266 {
1267         u64 delta = 0;
1268
1269         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1270                 return -1;
1271
1272         if (dso__load_all_kallsyms(dso, filename, map) < 0)
1273                 return -1;
1274
1275         if (kallsyms__delta(map, filename, &delta))
1276                 return -1;
1277
1278         symbols__fixup_duplicate(&dso->symbols[map->type]);
1279         symbols__fixup_end(&dso->symbols[map->type]);
1280
1281         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1282                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1283         else
1284                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1285
1286         if (!dso__load_kcore(dso, map, filename))
1287                 return dso__split_kallsyms_for_kcore(dso, map, filter);
1288         else
1289                 return dso__split_kallsyms(dso, map, delta, filter);
1290 }
1291
1292 static int dso__load_perf_map(struct dso *dso, struct map *map,
1293                               symbol_filter_t filter)
1294 {
1295         char *line = NULL;
1296         size_t n;
1297         FILE *file;
1298         int nr_syms = 0;
1299
1300         file = fopen(dso->long_name, "r");
1301         if (file == NULL)
1302                 goto out_failure;
1303
1304         while (!feof(file)) {
1305                 u64 start, size;
1306                 struct symbol *sym;
1307                 int line_len, len;
1308
1309                 line_len = getline(&line, &n, file);
1310                 if (line_len < 0)
1311                         break;
1312
1313                 if (!line)
1314                         goto out_failure;
1315
1316                 line[--line_len] = '\0'; /* \n */
1317
1318                 len = hex2u64(line, &start);
1319
1320                 len++;
1321                 if (len + 2 >= line_len)
1322                         continue;
1323
1324                 len += hex2u64(line + len, &size);
1325
1326                 len++;
1327                 if (len + 2 >= line_len)
1328                         continue;
1329
1330                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
1331
1332                 if (sym == NULL)
1333                         goto out_delete_line;
1334
1335                 if (filter && filter(map, sym))
1336                         symbol__delete(sym);
1337                 else {
1338                         symbols__insert(&dso->symbols[map->type], sym);
1339                         nr_syms++;
1340                 }
1341         }
1342
1343         free(line);
1344         fclose(file);
1345
1346         return nr_syms;
1347
1348 out_delete_line:
1349         free(line);
1350 out_failure:
1351         return -1;
1352 }
1353
1354 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1355                                            enum dso_binary_type type)
1356 {
1357         switch (type) {
1358         case DSO_BINARY_TYPE__JAVA_JIT:
1359         case DSO_BINARY_TYPE__DEBUGLINK:
1360         case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1361         case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1362         case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1363         case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1364         case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1365                 return !kmod && dso->kernel == DSO_TYPE_USER;
1366
1367         case DSO_BINARY_TYPE__KALLSYMS:
1368         case DSO_BINARY_TYPE__VMLINUX:
1369         case DSO_BINARY_TYPE__KCORE:
1370                 return dso->kernel == DSO_TYPE_KERNEL;
1371
1372         case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1373         case DSO_BINARY_TYPE__GUEST_VMLINUX:
1374         case DSO_BINARY_TYPE__GUEST_KCORE:
1375                 return dso->kernel == DSO_TYPE_GUEST_KERNEL;
1376
1377         case DSO_BINARY_TYPE__GUEST_KMODULE:
1378         case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1379         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1380         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1381                 /*
1382                  * kernel modules know their symtab type - it's set when
1383                  * creating a module dso in machine__findnew_module_map().
1384                  */
1385                 return kmod && dso->symtab_type == type;
1386
1387         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1388                 return true;
1389
1390         case DSO_BINARY_TYPE__NOT_FOUND:
1391         default:
1392                 return false;
1393         }
1394 }
1395
1396 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1397 {
1398         char *name;
1399         int ret = -1;
1400         u_int i;
1401         struct machine *machine;
1402         char *root_dir = (char *) "";
1403         int ss_pos = 0;
1404         struct symsrc ss_[2];
1405         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1406         bool kmod;
1407         unsigned char build_id[BUILD_ID_SIZE];
1408
1409         pthread_mutex_lock(&dso->lock);
1410
1411         /* check again under the dso->lock */
1412         if (dso__loaded(dso, map->type)) {
1413                 ret = 1;
1414                 goto out;
1415         }
1416
1417         if (dso->kernel) {
1418                 if (dso->kernel == DSO_TYPE_KERNEL)
1419                         ret = dso__load_kernel_sym(dso, map, filter);
1420                 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1421                         ret = dso__load_guest_kernel_sym(dso, map, filter);
1422
1423                 goto out;
1424         }
1425
1426         if (map->groups && map->groups->machine)
1427                 machine = map->groups->machine;
1428         else
1429                 machine = NULL;
1430
1431         dso->adjust_symbols = 0;
1432
1433         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1434                 struct stat st;
1435
1436                 if (lstat(dso->name, &st) < 0)
1437                         goto out;
1438
1439                 if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
1440                         pr_warning("File %s not owned by current user or root, "
1441                                    "ignoring it (use -f to override).\n", dso->name);
1442                         goto out;
1443                 }
1444
1445                 ret = dso__load_perf_map(dso, map, filter);
1446                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1447                                              DSO_BINARY_TYPE__NOT_FOUND;
1448                 goto out;
1449         }
1450
1451         if (machine)
1452                 root_dir = machine->root_dir;
1453
1454         name = malloc(PATH_MAX);
1455         if (!name)
1456                 goto out;
1457
1458         kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1459                 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1460                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1461                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1462
1463
1464         /*
1465          * Read the build id if possible. This is required for
1466          * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1467          */
1468         if (filename__read_build_id(dso->name, build_id, BUILD_ID_SIZE) > 0)
1469                 dso__set_build_id(dso, build_id);
1470
1471         /*
1472          * Iterate over candidate debug images.
1473          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1474          * and/or opd section) for processing.
1475          */
1476         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1477                 struct symsrc *ss = &ss_[ss_pos];
1478                 bool next_slot = false;
1479
1480                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1481
1482                 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1483                         continue;
1484
1485                 if (dso__read_binary_type_filename(dso, symtab_type,
1486                                                    root_dir, name, PATH_MAX))
1487                         continue;
1488
1489                 /* Name is now the name of the next image to try */
1490                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
1491                         continue;
1492
1493                 if (!syms_ss && symsrc__has_symtab(ss)) {
1494                         syms_ss = ss;
1495                         next_slot = true;
1496                         if (!dso->symsrc_filename)
1497                                 dso->symsrc_filename = strdup(name);
1498                 }
1499
1500                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1501                         runtime_ss = ss;
1502                         next_slot = true;
1503                 }
1504
1505                 if (next_slot) {
1506                         ss_pos++;
1507
1508                         if (syms_ss && runtime_ss)
1509                                 break;
1510                 } else {
1511                         symsrc__destroy(ss);
1512                 }
1513
1514         }
1515
1516         if (!runtime_ss && !syms_ss)
1517                 goto out_free;
1518
1519         if (runtime_ss && !syms_ss) {
1520                 syms_ss = runtime_ss;
1521         }
1522
1523         /* We'll have to hope for the best */
1524         if (!runtime_ss && syms_ss)
1525                 runtime_ss = syms_ss;
1526
1527         if (syms_ss)
1528                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, kmod);
1529         else
1530                 ret = -1;
1531
1532         if (ret > 0) {
1533                 int nr_plt;
1534
1535                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1536                 if (nr_plt > 0)
1537                         ret += nr_plt;
1538         }
1539
1540         for (; ss_pos > 0; ss_pos--)
1541                 symsrc__destroy(&ss_[ss_pos - 1]);
1542 out_free:
1543         free(name);
1544         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1545                 ret = 0;
1546 out:
1547         dso__set_loaded(dso, map->type);
1548         pthread_mutex_unlock(&dso->lock);
1549
1550         return ret;
1551 }
1552
1553 struct map *map_groups__find_by_name(struct map_groups *mg,
1554                                      enum map_type type, const char *name)
1555 {
1556         struct maps *maps = &mg->maps[type];
1557         struct map *map;
1558
1559         pthread_rwlock_rdlock(&maps->lock);
1560
1561         for (map = maps__first(maps); map; map = map__next(map)) {
1562                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1563                         goto out_unlock;
1564         }
1565
1566         map = NULL;
1567
1568 out_unlock:
1569         pthread_rwlock_unlock(&maps->lock);
1570         return map;
1571 }
1572
1573 int dso__load_vmlinux(struct dso *dso, struct map *map,
1574                       const char *vmlinux, bool vmlinux_allocated,
1575                       symbol_filter_t filter)
1576 {
1577         int err = -1;
1578         struct symsrc ss;
1579         char symfs_vmlinux[PATH_MAX];
1580         enum dso_binary_type symtab_type;
1581
1582         if (vmlinux[0] == '/')
1583                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1584         else
1585                 symbol__join_symfs(symfs_vmlinux, vmlinux);
1586
1587         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1588                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1589         else
1590                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1591
1592         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1593                 return -1;
1594
1595         err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1596         symsrc__destroy(&ss);
1597
1598         if (err > 0) {
1599                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1600                         dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1601                 else
1602                         dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1603                 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1604                 dso__set_loaded(dso, map->type);
1605                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1606         }
1607
1608         return err;
1609 }
1610
1611 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1612                            symbol_filter_t filter)
1613 {
1614         int i, err = 0;
1615         char *filename = NULL;
1616
1617         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1618                  vmlinux_path__nr_entries + 1);
1619
1620         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1621                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
1622                 if (err > 0)
1623                         goto out;
1624         }
1625
1626         if (!symbol_conf.ignore_vmlinux_buildid)
1627                 filename = dso__build_id_filename(dso, NULL, 0);
1628         if (filename != NULL) {
1629                 err = dso__load_vmlinux(dso, map, filename, true, filter);
1630                 if (err > 0)
1631                         goto out;
1632                 free(filename);
1633         }
1634 out:
1635         return err;
1636 }
1637
1638 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1639 {
1640         char kallsyms_filename[PATH_MAX];
1641         struct dirent *dent;
1642         int ret = -1;
1643         DIR *d;
1644
1645         d = opendir(dir);
1646         if (!d)
1647                 return -1;
1648
1649         while (1) {
1650                 dent = readdir(d);
1651                 if (!dent)
1652                         break;
1653                 if (dent->d_type != DT_DIR)
1654                         continue;
1655                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1656                           "%s/%s/kallsyms", dir, dent->d_name);
1657                 if (!validate_kcore_addresses(kallsyms_filename, map)) {
1658                         strlcpy(dir, kallsyms_filename, dir_sz);
1659                         ret = 0;
1660                         break;
1661                 }
1662         }
1663
1664         closedir(d);
1665
1666         return ret;
1667 }
1668
1669 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1670 {
1671         u8 host_build_id[BUILD_ID_SIZE];
1672         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1673         bool is_host = false;
1674         char path[PATH_MAX];
1675
1676         if (!dso->has_build_id) {
1677                 /*
1678                  * Last resort, if we don't have a build-id and couldn't find
1679                  * any vmlinux file, try the running kernel kallsyms table.
1680                  */
1681                 goto proc_kallsyms;
1682         }
1683
1684         if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1685                                  sizeof(host_build_id)) == 0)
1686                 is_host = dso__build_id_equal(dso, host_build_id);
1687
1688         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1689
1690         scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
1691                   sbuild_id);
1692
1693         /* Use /proc/kallsyms if possible */
1694         if (is_host) {
1695                 DIR *d;
1696                 int fd;
1697
1698                 /* If no cached kcore go with /proc/kallsyms */
1699                 d = opendir(path);
1700                 if (!d)
1701                         goto proc_kallsyms;
1702                 closedir(d);
1703
1704                 /*
1705                  * Do not check the build-id cache, until we know we cannot use
1706                  * /proc/kcore.
1707                  */
1708                 fd = open("/proc/kcore", O_RDONLY);
1709                 if (fd != -1) {
1710                         close(fd);
1711                         /* If module maps match go with /proc/kallsyms */
1712                         if (!validate_kcore_addresses("/proc/kallsyms", map))
1713                                 goto proc_kallsyms;
1714                 }
1715
1716                 /* Find kallsyms in build-id cache with kcore */
1717                 if (!find_matching_kcore(map, path, sizeof(path)))
1718                         return strdup(path);
1719
1720                 goto proc_kallsyms;
1721         }
1722
1723         /* Find kallsyms in build-id cache with kcore */
1724         if (!find_matching_kcore(map, path, sizeof(path)))
1725                 return strdup(path);
1726
1727         scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
1728                   buildid_dir, sbuild_id);
1729
1730         if (access(path, F_OK)) {
1731                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1732                        sbuild_id);
1733                 return NULL;
1734         }
1735
1736         return strdup(path);
1737
1738 proc_kallsyms:
1739         return strdup("/proc/kallsyms");
1740 }
1741
1742 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1743                                 symbol_filter_t filter)
1744 {
1745         int err;
1746         const char *kallsyms_filename = NULL;
1747         char *kallsyms_allocated_filename = NULL;
1748         /*
1749          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1750          * it and only it, reporting errors to the user if it cannot be used.
1751          *
1752          * For instance, try to analyse an ARM perf.data file _without_ a
1753          * build-id, or if the user specifies the wrong path to the right
1754          * vmlinux file, obviously we can't fallback to another vmlinux (a
1755          * x86_86 one, on the machine where analysis is being performed, say),
1756          * or worse, /proc/kallsyms.
1757          *
1758          * If the specified file _has_ a build-id and there is a build-id
1759          * section in the perf.data file, we will still do the expected
1760          * validation in dso__load_vmlinux and will bail out if they don't
1761          * match.
1762          */
1763         if (symbol_conf.kallsyms_name != NULL) {
1764                 kallsyms_filename = symbol_conf.kallsyms_name;
1765                 goto do_kallsyms;
1766         }
1767
1768         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1769                 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
1770                                          false, filter);
1771         }
1772
1773         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1774                 err = dso__load_vmlinux_path(dso, map, filter);
1775                 if (err > 0)
1776                         return err;
1777         }
1778
1779         /* do not try local files if a symfs was given */
1780         if (symbol_conf.symfs[0] != 0)
1781                 return -1;
1782
1783         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1784         if (!kallsyms_allocated_filename)
1785                 return -1;
1786
1787         kallsyms_filename = kallsyms_allocated_filename;
1788
1789 do_kallsyms:
1790         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1791         if (err > 0)
1792                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1793         free(kallsyms_allocated_filename);
1794
1795         if (err > 0 && !dso__is_kcore(dso)) {
1796                 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
1797                 dso__set_long_name(dso, "[kernel.kallsyms]", false);
1798                 map__fixup_start(map);
1799                 map__fixup_end(map);
1800         }
1801
1802         return err;
1803 }
1804
1805 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1806                                       symbol_filter_t filter)
1807 {
1808         int err;
1809         const char *kallsyms_filename = NULL;
1810         struct machine *machine;
1811         char path[PATH_MAX];
1812
1813         if (!map->groups) {
1814                 pr_debug("Guest kernel map hasn't the point to groups\n");
1815                 return -1;
1816         }
1817         machine = map->groups->machine;
1818
1819         if (machine__is_default_guest(machine)) {
1820                 /*
1821                  * if the user specified a vmlinux filename, use it and only
1822                  * it, reporting errors to the user if it cannot be used.
1823                  * Or use file guest_kallsyms inputted by user on commandline
1824                  */
1825                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1826                         err = dso__load_vmlinux(dso, map,
1827                                                 symbol_conf.default_guest_vmlinux_name,
1828                                                 false, filter);
1829                         return err;
1830                 }
1831
1832                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1833                 if (!kallsyms_filename)
1834                         return -1;
1835         } else {
1836                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1837                 kallsyms_filename = path;
1838         }
1839
1840         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1841         if (err > 0)
1842                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1843         if (err > 0 && !dso__is_kcore(dso)) {
1844                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1845                 machine__mmap_name(machine, path, sizeof(path));
1846                 dso__set_long_name(dso, strdup(path), true);
1847                 map__fixup_start(map);
1848                 map__fixup_end(map);
1849         }
1850
1851         return err;
1852 }
1853
1854 static void vmlinux_path__exit(void)
1855 {
1856         while (--vmlinux_path__nr_entries >= 0)
1857                 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1858         vmlinux_path__nr_entries = 0;
1859
1860         zfree(&vmlinux_path);
1861 }
1862
1863 static int vmlinux_path__init(struct perf_env *env)
1864 {
1865         struct utsname uts;
1866         char bf[PATH_MAX];
1867         char *kernel_version;
1868
1869         vmlinux_path = malloc(sizeof(char *) * 6);
1870         if (vmlinux_path == NULL)
1871                 return -1;
1872
1873         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1874         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1875                 goto out_fail;
1876         ++vmlinux_path__nr_entries;
1877         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1878         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1879                 goto out_fail;
1880         ++vmlinux_path__nr_entries;
1881
1882         /* only try kernel version if no symfs was given */
1883         if (symbol_conf.symfs[0] != 0)
1884                 return 0;
1885
1886         if (env) {
1887                 kernel_version = env->os_release;
1888         } else {
1889                 if (uname(&uts) < 0)
1890                         goto out_fail;
1891
1892                 kernel_version = uts.release;
1893         }
1894
1895         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", kernel_version);
1896         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1897         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1898                 goto out_fail;
1899         ++vmlinux_path__nr_entries;
1900         snprintf(bf, sizeof(bf), "/usr/lib/debug/boot/vmlinux-%s",
1901                  kernel_version);
1902         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1903         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1904                 goto out_fail;
1905         ++vmlinux_path__nr_entries;
1906         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", kernel_version);
1907         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1908         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1909                 goto out_fail;
1910         ++vmlinux_path__nr_entries;
1911         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1912                  kernel_version);
1913         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1914         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1915                 goto out_fail;
1916         ++vmlinux_path__nr_entries;
1917
1918         return 0;
1919
1920 out_fail:
1921         vmlinux_path__exit();
1922         return -1;
1923 }
1924
1925 int setup_list(struct strlist **list, const char *list_str,
1926                       const char *list_name)
1927 {
1928         if (list_str == NULL)
1929                 return 0;
1930
1931         *list = strlist__new(list_str, NULL);
1932         if (!*list) {
1933                 pr_err("problems parsing %s list\n", list_name);
1934                 return -1;
1935         }
1936
1937         symbol_conf.has_filter = true;
1938         return 0;
1939 }
1940
1941 int setup_intlist(struct intlist **list, const char *list_str,
1942                   const char *list_name)
1943 {
1944         if (list_str == NULL)
1945                 return 0;
1946
1947         *list = intlist__new(list_str);
1948         if (!*list) {
1949                 pr_err("problems parsing %s list\n", list_name);
1950                 return -1;
1951         }
1952         return 0;
1953 }
1954
1955 static bool symbol__read_kptr_restrict(void)
1956 {
1957         bool value = false;
1958
1959         if (geteuid() != 0) {
1960                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1961                 if (fp != NULL) {
1962                         char line[8];
1963
1964                         if (fgets(line, sizeof(line), fp) != NULL)
1965                                 value = atoi(line) != 0;
1966
1967                         fclose(fp);
1968                 }
1969         }
1970
1971         return value;
1972 }
1973
1974 int symbol__init(struct perf_env *env)
1975 {
1976         const char *symfs;
1977
1978         if (symbol_conf.initialized)
1979                 return 0;
1980
1981         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1982
1983         symbol__elf_init();
1984
1985         if (symbol_conf.sort_by_name)
1986                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1987                                           sizeof(struct symbol));
1988
1989         if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
1990                 return -1;
1991
1992         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1993                 pr_err("'.' is the only non valid --field-separator argument\n");
1994                 return -1;
1995         }
1996
1997         if (setup_list(&symbol_conf.dso_list,
1998                        symbol_conf.dso_list_str, "dso") < 0)
1999                 return -1;
2000
2001         if (setup_list(&symbol_conf.comm_list,
2002                        symbol_conf.comm_list_str, "comm") < 0)
2003                 goto out_free_dso_list;
2004
2005         if (setup_intlist(&symbol_conf.pid_list,
2006                        symbol_conf.pid_list_str, "pid") < 0)
2007                 goto out_free_comm_list;
2008
2009         if (setup_intlist(&symbol_conf.tid_list,
2010                        symbol_conf.tid_list_str, "tid") < 0)
2011                 goto out_free_pid_list;
2012
2013         if (setup_list(&symbol_conf.sym_list,
2014                        symbol_conf.sym_list_str, "symbol") < 0)
2015                 goto out_free_tid_list;
2016
2017         /*
2018          * A path to symbols of "/" is identical to ""
2019          * reset here for simplicity.
2020          */
2021         symfs = realpath(symbol_conf.symfs, NULL);
2022         if (symfs == NULL)
2023                 symfs = symbol_conf.symfs;
2024         if (strcmp(symfs, "/") == 0)
2025                 symbol_conf.symfs = "";
2026         if (symfs != symbol_conf.symfs)
2027                 free((void *)symfs);
2028
2029         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2030
2031         symbol_conf.initialized = true;
2032         return 0;
2033
2034 out_free_tid_list:
2035         intlist__delete(symbol_conf.tid_list);
2036 out_free_pid_list:
2037         intlist__delete(symbol_conf.pid_list);
2038 out_free_comm_list:
2039         strlist__delete(symbol_conf.comm_list);
2040 out_free_dso_list:
2041         strlist__delete(symbol_conf.dso_list);
2042         return -1;
2043 }
2044
2045 void symbol__exit(void)
2046 {
2047         if (!symbol_conf.initialized)
2048                 return;
2049         strlist__delete(symbol_conf.sym_list);
2050         strlist__delete(symbol_conf.dso_list);
2051         strlist__delete(symbol_conf.comm_list);
2052         intlist__delete(symbol_conf.tid_list);
2053         intlist__delete(symbol_conf.pid_list);
2054         vmlinux_path__exit();
2055         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2056         symbol_conf.initialized = false;
2057 }