tools/perf/util/symbol.c

   1 #define _GNU_SOURCE
   2 #include <ctype.h>
   3 #include <dirent.h>
   4 #include <errno.h>
   5 #include <libgen.h>
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <sys/types.h>
  10 #include <sys/stat.h>
  11 #include <sys/param.h>
  12 #include <fcntl.h>
  13 #include <unistd.h>
  14 #include <inttypes.h>
  15 #include "build-id.h"
  16 #include "debug.h"
  17 #include "symbol.h"
  18 #include "strlist.h"
  19
  20 #include <libelf.h>
  21 #include <gelf.h>
  22 #include <elf.h>
  23 #include <limits.h>
  24 #include <sys/utsname.h>
  25
  26 #ifndef KSYM_NAME_LEN
  27 #define KSYM_NAME_LEN 128
  28 #endif
  29
  30 #ifndef NT_GNU_BUILD_ID
  31 #define NT_GNU_BUILD_ID 3
  32 #endif
  33
  34 static bool dso__build_id_equal(const struct dso *dso, u8 *build_id);
  35 static int elf_read_build_id(Elf *elf, void *bf, size_t size);
  36 static void dsos__add(struct list_head *head, struct dso *dso);
  37 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
  38 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
  39                                 symbol_filter_t filter);
  40 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
  41                         symbol_filter_t filter);
  42 static int vmlinux_path__nr_entries;
  43 static char **vmlinux_path;
  44
  45 struct symbol_conf symbol_conf = {
  46         .exclude_other    = true,
  47         .use_modules      = true,
  48         .try_vmlinux_path = true,
  49         .symfs            = "",
  50 };
  51
  52 int dso__name_len(const struct dso *dso)
  53 {
  54         if (verbose)
  55                 return dso->long_name_len;
  56
  57         return dso->short_name_len;
  58 }
  59
  60 bool dso__loaded(const struct dso *dso, enum map_type type)
  61 {
  62         return dso->loaded & (1 << type);
  63 }
  64
  65 bool dso__sorted_by_name(const struct dso *dso, enum map_type type)
  66 {
  67         return dso->sorted_by_name & (1 << type);
  68 }
  69
  70 static void dso__set_sorted_by_name(struct dso *dso, enum map_type type)
  71 {
  72         dso->sorted_by_name |= (1 << type);
  73 }
  74
  75 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  76 {
  77         switch (map_type) {
  78         case MAP__FUNCTION:
  79                 return symbol_type == 'T' || symbol_type == 'W';
  80         case MAP__VARIABLE:
  81                 return symbol_type == 'D' || symbol_type == 'd';
  82         default:
  83                 return false;
  84         }
  85 }
  86
  87 static void symbols__fixup_end(struct rb_root *symbols)
  88 {
  89         struct rb_node *nd, *prevnd = rb_first(symbols);
  90         struct symbol *curr, *prev;
  91
  92         if (prevnd == NULL)
  93                 return;
  94
  95         curr = rb_entry(prevnd, struct symbol, rb_node);
  96
  97         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  98                 prev = curr;
  99                 curr = rb_entry(nd, struct symbol, rb_node);
 100
 101                 if (prev->end == prev->start && prev->end != curr->start)
 102                         prev->end = curr->start - 1;
 103         }
 104
 105         /* Last entry */
 106         if (curr->end == curr->start)
 107                 curr->end = roundup(curr->start, 4096);
 108 }
 109
 110 static void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 111 {
 112         struct map *prev, *curr;
 113         struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
 114
 115         if (prevnd == NULL)
 116                 return;
 117
 118         curr = rb_entry(prevnd, struct map, rb_node);
 119
 120         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 121                 prev = curr;
 122                 curr = rb_entry(nd, struct map, rb_node);
 123                 prev->end = curr->start - 1;
 124         }
 125
 126         /*
 127          * We still haven't the actual symbols, so guess the
 128          * last map final address.
 129          */
 130         curr->end = ~0ULL;
 131 }
 132
 133 static void map_groups__fixup_end(struct map_groups *mg)
 134 {
 135         int i;
 136         for (i = 0; i < MAP__NR_TYPES; ++i)
 137                 __map_groups__fixup_end(mg, i);
 138 }
 139
 140 static struct symbol *symbol__new(u64 start, u64 len, u8 binding,
 141                                   const char *name)
 142 {
 143         size_t namelen = strlen(name) + 1;
 144         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 145                                         sizeof(*sym) + namelen));
 146         if (sym == NULL)
 147                 return NULL;
 148
 149         if (symbol_conf.priv_size)
 150                 sym = ((void *)sym) + symbol_conf.priv_size;
 151
 152         sym->start   = start;
 153         sym->end     = len ? start + len - 1 : start;
 154         sym->binding = binding;
 155         sym->namelen = namelen - 1;
 156
 157         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 158                   __func__, name, start, sym->end);
 159         memcpy(sym->name, name, namelen);
 160
 161         return sym;
 162 }
 163
 164 void symbol__delete(struct symbol *sym)
 165 {
 166         free(((void *)sym) - symbol_conf.priv_size);
 167 }
 168
 169 static size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 170 {
 171         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 172                        sym->start, sym->end,
 173                        sym->binding == STB_GLOBAL ? 'g' :
 174                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 175                        sym->name);
 176 }
 177
 178 void dso__set_long_name(struct dso *dso, char *name)
 179 {
 180         if (name == NULL)
 181                 return;
 182         dso->long_name = name;
 183         dso->long_name_len = strlen(name);
 184 }
 185
 186 static void dso__set_short_name(struct dso *dso, const char *name)
 187 {
 188         if (name == NULL)
 189                 return;
 190         dso->short_name = name;
 191         dso->short_name_len = strlen(name);
 192 }
 193
 194 static void dso__set_basename(struct dso *dso)
 195 {
 196         dso__set_short_name(dso, basename(dso->long_name));
 197 }
 198
 199 struct dso *dso__new(const char *name)
 200 {
 201         struct dso *dso = calloc(1, sizeof(*dso) + strlen(name) + 1);
 202
 203         if (dso != NULL) {
 204                 int i;
 205                 strcpy(dso->name, name);
 206                 dso__set_long_name(dso, dso->name);
 207                 dso__set_short_name(dso, dso->name);
 208                 for (i = 0; i < MAP__NR_TYPES; ++i)
 209                         dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
 210                 dso->symtab_type = SYMTAB__NOT_FOUND;
 211                 dso->loaded = 0;
 212                 dso->sorted_by_name = 0;
 213                 dso->has_build_id = 0;
 214                 dso->kernel = DSO_TYPE_USER;
 215                 INIT_LIST_HEAD(&dso->node);
 216         }
 217
 218         return dso;
 219 }
 220
 221 static void symbols__delete(struct rb_root *symbols)
 222 {
 223         struct symbol *pos;
 224         struct rb_node *next = rb_first(symbols);
 225
 226         while (next) {
 227                 pos = rb_entry(next, struct symbol, rb_node);
 228                 next = rb_next(&pos->rb_node);
 229                 rb_erase(&pos->rb_node, symbols);
 230                 symbol__delete(pos);
 231         }
 232 }
 233
 234 void dso__delete(struct dso *dso)
 235 {
 236         int i;
 237         for (i = 0; i < MAP__NR_TYPES; ++i)
 238                 symbols__delete(&dso->symbols[i]);
 239         if (dso->sname_alloc)
 240                 free((char *)dso->short_name);
 241         if (dso->lname_alloc)
 242                 free(dso->long_name);
 243         free(dso);
 244 }
 245
 246 void dso__set_build_id(struct dso *dso, void *build_id)
 247 {
 248         memcpy(dso->build_id, build_id, sizeof(dso->build_id));
 249         dso->has_build_id = 1;
 250 }
 251
 252 static void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 253 {
 254         struct rb_node **p = &symbols->rb_node;
 255         struct rb_node *parent = NULL;
 256         const u64 ip = sym->start;
 257         struct symbol *s;
 258
 259         while (*p != NULL) {
 260                 parent = *p;
 261                 s = rb_entry(parent, struct symbol, rb_node);
 262                 if (ip < s->start)
 263                         p = &(*p)->rb_left;
 264                 else
 265                         p = &(*p)->rb_right;
 266         }
 267         rb_link_node(&sym->rb_node, parent, p);
 268         rb_insert_color(&sym->rb_node, symbols);
 269 }
 270
 271 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 272 {
 273         struct rb_node *n;
 274
 275         if (symbols == NULL)
 276                 return NULL;
 277
 278         n = symbols->rb_node;
 279
 280         while (n) {
 281                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 282
 283                 if (ip < s->start)
 284                         n = n->rb_left;
 285                 else if (ip > s->end)
 286                         n = n->rb_right;
 287                 else
 288                         return s;
 289         }
 290
 291         return NULL;
 292 }
 293
 294 struct symbol_name_rb_node {
 295         struct rb_node  rb_node;
 296         struct symbol   sym;
 297 };
 298
 299 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 300 {
 301         struct rb_node **p = &symbols->rb_node;
 302         struct rb_node *parent = NULL;
 303         struct symbol_name_rb_node *symn, *s;
 304
 305         symn = container_of(sym, struct symbol_name_rb_node, sym);
 306
 307         while (*p != NULL) {
 308                 parent = *p;
 309                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 310                 if (strcmp(sym->name, s->sym.name) < 0)
 311                         p = &(*p)->rb_left;
 312                 else
 313                         p = &(*p)->rb_right;
 314         }
 315         rb_link_node(&symn->rb_node, parent, p);
 316         rb_insert_color(&symn->rb_node, symbols);
 317 }
 318
 319 static void symbols__sort_by_name(struct rb_root *symbols,
 320                                   struct rb_root *source)
 321 {
 322         struct rb_node *nd;
 323
 324         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 325                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 326                 symbols__insert_by_name(symbols, pos);
 327         }
 328 }
 329
 330 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 331                                             const char *name)
 332 {
 333         struct rb_node *n;
 334
 335         if (symbols == NULL)
 336                 return NULL;
 337
 338         n = symbols->rb_node;
 339
 340         while (n) {
 341                 struct symbol_name_rb_node *s;
 342                 int cmp;
 343
 344                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 345                 cmp = strcmp(name, s->sym.name);
 346
 347                 if (cmp < 0)
 348                         n = n->rb_left;
 349                 else if (cmp > 0)
 350                         n = n->rb_right;
 351                 else
 352                         return &s->sym;
 353         }
 354
 355         return NULL;
 356 }
 357
 358 struct symbol *dso__find_symbol(struct dso *dso,
 359                                 enum map_type type, u64 addr)
 360 {
 361         return symbols__find(&dso->symbols[type], addr);
 362 }
 363
 364 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 365                                         const char *name)
 366 {
 367         return symbols__find_by_name(&dso->symbol_names[type], name);
 368 }
 369
 370 void dso__sort_by_name(struct dso *dso, enum map_type type)
 371 {
 372         dso__set_sorted_by_name(dso, type);
 373         return symbols__sort_by_name(&dso->symbol_names[type],
 374                                      &dso->symbols[type]);
 375 }
 376
 377 int build_id__sprintf(const u8 *build_id, int len, char *bf)
 378 {
 379         char *bid = bf;
 380         const u8 *raw = build_id;
 381         int i;
 382
 383         for (i = 0; i < len; ++i) {
 384                 sprintf(bid, "%02x", *raw);
 385                 ++raw;
 386                 bid += 2;
 387         }
 388
 389         return raw - build_id;
 390 }
 391
 392 size_t dso__fprintf_buildid(struct dso *dso, FILE *fp)
 393 {
 394         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
 395
 396         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
 397         return fprintf(fp, "%s", sbuild_id);
 398 }
 399
 400 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 401                                     enum map_type type, FILE *fp)
 402 {
 403         size_t ret = 0;
 404         struct rb_node *nd;
 405         struct symbol_name_rb_node *pos;
 406
 407         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 408                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 409                 fprintf(fp, "%s\n", pos->sym.name);
 410         }
 411
 412         return ret;
 413 }
 414
 415 size_t dso__fprintf(struct dso *dso, enum map_type type, FILE *fp)
 416 {
 417         struct rb_node *nd;
 418         size_t ret = fprintf(fp, "dso: %s (", dso->short_name);
 419
 420         if (dso->short_name != dso->long_name)
 421                 ret += fprintf(fp, "%s, ", dso->long_name);
 422         ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
 423                        dso->loaded ? "" : "NOT ");
 424         ret += dso__fprintf_buildid(dso, fp);
 425         ret += fprintf(fp, ")\n");
 426         for (nd = rb_first(&dso->symbols[type]); nd; nd = rb_next(nd)) {
 427                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 428                 ret += symbol__fprintf(pos, fp);
 429         }
 430
 431         return ret;
 432 }
 433
 434 int kallsyms__parse(const char *filename, void *arg,
 435                     int (*process_symbol)(void *arg, const char *name,
 436                                           char type, u64 start, u64 end))
 437 {
 438         char *line = NULL;
 439         size_t n;
 440         int err = -1;
 441         u64 prev_start = 0;
 442         char prev_symbol_type = 0;
 443         char *prev_symbol_name;
 444         FILE *file = fopen(filename, "r");
 445
 446         if (file == NULL)
 447                 goto out_failure;
 448
 449         prev_symbol_name = malloc(KSYM_NAME_LEN);
 450         if (prev_symbol_name == NULL)
 451                 goto out_close;
 452
 453         err = 0;
 454
 455         while (!feof(file)) {
 456                 u64 start;
 457                 int line_len, len;
 458                 char symbol_type;
 459                 char *symbol_name;
 460
 461                 line_len = getline(&line, &n, file);
 462                 if (line_len < 0 || !line)
 463                         break;
 464
 465                 line[--line_len] = '\0'; /* \n */
 466
 467                 len = hex2u64(line, &start);
 468
 469                 len++;
 470                 if (len + 2 >= line_len)
 471                         continue;
 472
 473                 symbol_type = toupper(line[len]);
 474                 len += 2;
 475                 symbol_name = line + len;
 476                 len = line_len - len;
 477
 478                 if (len >= KSYM_NAME_LEN) {
 479                         err = -1;
 480                         break;
 481                 }
 482
 483                 if (prev_symbol_type) {
 484                         u64 end = start;
 485                         if (end != prev_start)
 486                                 --end;
 487                         err = process_symbol(arg, prev_symbol_name,
 488                                              prev_symbol_type, prev_start, end);
 489                         if (err)
 490                                 break;
 491                 }
 492
 493                 memcpy(prev_symbol_name, symbol_name, len + 1);
 494                 prev_symbol_type = symbol_type;
 495                 prev_start = start;
 496         }
 497
 498         free(prev_symbol_name);
 499         free(line);
 500 out_close:
 501         fclose(file);
 502         return err;
 503
 504 out_failure:
 505         return -1;
 506 }
 507
 508 struct process_kallsyms_args {
 509         struct map *map;
 510         struct dso *dso;
 511 };
 512
 513 static u8 kallsyms2elf_type(char type)
 514 {
 515         if (type == 'W')
 516                 return STB_WEAK;
 517
 518         return isupper(type) ? STB_GLOBAL : STB_LOCAL;
 519 }
 520
 521 static int map__process_kallsym_symbol(void *arg, const char *name,
 522                                        char type, u64 start, u64 end)
 523 {
 524         struct symbol *sym;
 525         struct process_kallsyms_args *a = arg;
 526         struct rb_root *root = &a->dso->symbols[a->map->type];
 527
 528         if (!symbol_type__is_a(type, a->map->type))
 529                 return 0;
 530
 531         sym = symbol__new(start, end - start + 1,
 532                           kallsyms2elf_type(type), name);
 533         if (sym == NULL)
 534                 return -ENOMEM;
 535         /*
 536          * We will pass the symbols to the filter later, in
 537          * map__split_kallsyms, when we have split the maps per module
 538          */
 539         symbols__insert(root, sym);
 540
 541         return 0;
 542 }
 543
 544 /*
 545  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 546  * so that we can in the next step set the symbol ->end address and then
 547  * call kernel_maps__split_kallsyms.
 548  */
 549 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 550                                   struct map *map)
 551 {
 552         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 553         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 554 }
 555
 556 /*
 557  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 558  * kernel range is broken in several maps, named [kernel].N, as we don't have
 559  * the original ELF section names vmlinux have.
 560  */
 561 static int dso__split_kallsyms(struct dso *dso, struct map *map,
 562                                symbol_filter_t filter)
 563 {
 564         struct map_groups *kmaps = map__kmap(map)->kmaps;
 565         struct machine *machine = kmaps->machine;
 566         struct map *curr_map = map;
 567         struct symbol *pos;
 568         int count = 0, moved = 0;
 569         struct rb_root *root = &dso->symbols[map->type];
 570         struct rb_node *next = rb_first(root);
 571         int kernel_range = 0;
 572
 573         while (next) {
 574                 char *module;
 575
 576                 pos = rb_entry(next, struct symbol, rb_node);
 577                 next = rb_next(&pos->rb_node);
 578
 579                 module = strchr(pos->name, '\t');
 580                 if (module) {
 581                         if (!symbol_conf.use_modules)
 582                                 goto discard_symbol;
 583
 584                         *module++ = '\0';
 585
 586                         if (strcmp(curr_map->dso->short_name, module)) {
 587                                 if (curr_map != map &&
 588                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 589                                     machine__is_default_guest(machine)) {
 590                                         /*
 591                                          * We assume all symbols of a module are
 592                                          * continuous in * kallsyms, so curr_map
 593                                          * points to a module and all its
 594                                          * symbols are in its kmap. Mark it as
 595                                          * loaded.
 596                                          */
 597                                         dso__set_loaded(curr_map->dso,
 598                                                         curr_map->type);
 599                                 }
 600
 601                                 curr_map = map_groups__find_by_name(kmaps,
 602                                                         map->type, module);
 603                                 if (curr_map == NULL) {
 604                                         pr_debug("%s/proc/{kallsyms,modules} "
 605                                                  "inconsistency while looking "
 606                                                  "for \"%s\" module!\n",
 607                                                  machine->root_dir, module);
 608                                         curr_map = map;
 609                                         goto discard_symbol;
 610                                 }
 611
 612                                 if (curr_map->dso->loaded &&
 613                                     !machine__is_default_guest(machine))
 614                                         goto discard_symbol;
 615                         }
 616                         /*
 617                          * So that we look just like we get from .ko files,
 618                          * i.e. not prelinked, relative to map->start.
 619                          */
 620                         pos->start = curr_map->map_ip(curr_map, pos->start);
 621                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 622                 } else if (curr_map != map) {
 623                         char dso_name[PATH_MAX];
 624                         struct dso *ndso;
 625
 626                         if (count == 0) {
 627                                 curr_map = map;
 628                                 goto filter_symbol;
 629                         }
 630
 631                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 632                                 snprintf(dso_name, sizeof(dso_name),
 633                                         "[guest.kernel].%d",
 634                                         kernel_range++);
 635                         else
 636                                 snprintf(dso_name, sizeof(dso_name),
 637                                         "[kernel].%d",
 638                                         kernel_range++);
 639
 640                         ndso = dso__new(dso_name);
 641                         if (ndso == NULL)
 642                                 return -1;
 643
 644                         ndso->kernel = dso->kernel;
 645
 646                         curr_map = map__new2(pos->start, ndso, map->type);
 647                         if (curr_map == NULL) {
 648                                 dso__delete(ndso);
 649                                 return -1;
 650                         }
 651
 652                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 653                         map_groups__insert(kmaps, curr_map);
 654                         ++kernel_range;
 655                 }
 656 filter_symbol:
 657                 if (filter && filter(curr_map, pos)) {
 658 discard_symbol:         rb_erase(&pos->rb_node, root);
 659                         symbol__delete(pos);
 660                 } else {
 661                         if (curr_map != map) {
 662                                 rb_erase(&pos->rb_node, root);
 663                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 664                                 ++moved;
 665                         } else
 666                                 ++count;
 667                 }
 668         }
 669
 670         if (curr_map != map &&
 671             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 672             machine__is_default_guest(kmaps->machine)) {
 673                 dso__set_loaded(curr_map->dso, curr_map->type);
 674         }
 675
 676         return count + moved;
 677 }
 678
 679 static bool symbol__restricted_filename(const char *filename,
 680                                         const char *restricted_filename)
 681 {
 682         bool restricted = false;
 683
 684         if (symbol_conf.kptr_restrict) {
 685                 char *r = realpath(filename, NULL);
 686
 687                 if (r != NULL) {
 688                         restricted = strcmp(r, restricted_filename) == 0;
 689                         free(r);
 690                         return restricted;
 691                 }
 692         }
 693
 694         return restricted;
 695 }
 696
 697 int dso__load_kallsyms(struct dso *dso, const char *filename,
 698                        struct map *map, symbol_filter_t filter)
 699 {
 700         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
 701                 return -1;
 702
 703         if (dso__load_all_kallsyms(dso, filename, map) < 0)
 704                 return -1;
 705
 706         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 707                 dso->symtab_type = SYMTAB__GUEST_KALLSYMS;
 708         else
 709                 dso->symtab_type = SYMTAB__KALLSYMS;
 710
 711         return dso__split_kallsyms(dso, map, filter);
 712 }
 713
 714 static int dso__load_perf_map(struct dso *dso, struct map *map,
 715                               symbol_filter_t filter)
 716 {
 717         char *line = NULL;
 718         size_t n;
 719         FILE *file;
 720         int nr_syms = 0;
 721
 722         file = fopen(dso->long_name, "r");
 723         if (file == NULL)
 724                 goto out_failure;
 725
 726         while (!feof(file)) {
 727                 u64 start, size;
 728                 struct symbol *sym;
 729                 int line_len, len;
 730
 731                 line_len = getline(&line, &n, file);
 732                 if (line_len < 0)
 733                         break;
 734
 735                 if (!line)
 736                         goto out_failure;
 737
 738                 line[--line_len] = '\0'; /* \n */
 739
 740                 len = hex2u64(line, &start);
 741
 742                 len++;
 743                 if (len + 2 >= line_len)
 744                         continue;
 745
 746                 len += hex2u64(line + len, &size);
 747
 748                 len++;
 749                 if (len + 2 >= line_len)
 750                         continue;
 751
 752                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
 753
 754                 if (sym == NULL)
 755                         goto out_delete_line;
 756
 757                 if (filter && filter(map, sym))
 758                         symbol__delete(sym);
 759                 else {
 760                         symbols__insert(&dso->symbols[map->type], sym);
 761                         nr_syms++;
 762                 }
 763         }
 764
 765         free(line);
 766         fclose(file);
 767
 768         return nr_syms;
 769
 770 out_delete_line:
 771         free(line);
 772 out_failure:
 773         return -1;
 774 }
 775
 776 /**
 777  * elf_symtab__for_each_symbol - iterate thru all the symbols
 778  *
 779  * @syms: struct elf_symtab instance to iterate
 780  * @idx: uint32_t idx
 781  * @sym: GElf_Sym iterator
 782  */
 783 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
 784         for (idx = 0, gelf_getsym(syms, idx, &sym);\
 785              idx < nr_syms; \
 786              idx++, gelf_getsym(syms, idx, &sym))
 787
 788 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
 789 {
 790         return GELF_ST_TYPE(sym->st_info);
 791 }
 792
 793 static inline int elf_sym__is_function(const GElf_Sym *sym)
 794 {
 795         return elf_sym__type(sym) == STT_FUNC &&
 796                sym->st_name != 0 &&
 797                sym->st_shndx != SHN_UNDEF;
 798 }
 799
 800 static inline bool elf_sym__is_object(const GElf_Sym *sym)
 801 {
 802         return elf_sym__type(sym) == STT_OBJECT &&
 803                 sym->st_name != 0 &&
 804                 sym->st_shndx != SHN_UNDEF;
 805 }
 806
 807 static inline int elf_sym__is_label(const GElf_Sym *sym)
 808 {
 809         return elf_sym__type(sym) == STT_NOTYPE &&
 810                 sym->st_name != 0 &&
 811                 sym->st_shndx != SHN_UNDEF &&
 812                 sym->st_shndx != SHN_ABS;
 813 }
 814
 815 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
 816                                         const Elf_Data *secstrs)
 817 {
 818         return secstrs->d_buf + shdr->sh_name;
 819 }
 820
 821 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
 822                                         const Elf_Data *secstrs)
 823 {
 824         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
 825 }
 826
 827 static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
 828                                     const Elf_Data *secstrs)
 829 {
 830         return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
 831 }
 832
 833 static inline const char *elf_sym__name(const GElf_Sym *sym,
 834                                         const Elf_Data *symstrs)
 835 {
 836         return symstrs->d_buf + sym->st_name;
 837 }
 838
 839 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 840                                     GElf_Shdr *shp, const char *name,
 841                                     size_t *idx)
 842 {
 843         Elf_Scn *sec = NULL;
 844         size_t cnt = 1;
 845
 846         while ((sec = elf_nextscn(elf, sec)) != NULL) {
 847                 char *str;
 848
 849                 gelf_getshdr(sec, shp);
 850                 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
 851                 if (!strcmp(name, str)) {
 852                         if (idx)
 853                                 *idx = cnt;
 854                         break;
 855                 }
 856                 ++cnt;
 857         }
 858
 859         return sec;
 860 }
 861
 862 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
 863         for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
 864              idx < nr_entries; \
 865              ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
 866
 867 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
 868         for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
 869              idx < nr_entries; \
 870              ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
 871
 872 /*
 873  * We need to check if we have a .dynsym, so that we can handle the
 874  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
 875  * .dynsym or .symtab).
 876  * And always look at the original dso, not at debuginfo packages, that
 877  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
 878  */
 879 static int dso__synthesize_plt_symbols(struct  dso *dso, struct map *map,
 880                                        symbol_filter_t filter)
 881 {
 882         uint32_t nr_rel_entries, idx;
 883         GElf_Sym sym;
 884         u64 plt_offset;
 885         GElf_Shdr shdr_plt;
 886         struct symbol *f;
 887         GElf_Shdr shdr_rel_plt, shdr_dynsym;
 888         Elf_Data *reldata, *syms, *symstrs;
 889         Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
 890         size_t dynsym_idx;
 891         GElf_Ehdr ehdr;
 892         char sympltname[1024];
 893         Elf *elf;
 894         int nr = 0, symidx, fd, err = 0;
 895         char name[PATH_MAX];
 896
 897         snprintf(name, sizeof(name), "%s%s",
 898                  symbol_conf.symfs, dso->long_name);
 899         fd = open(name, O_RDONLY);
 900         if (fd < 0)
 901                 goto out;
 902
 903         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 904         if (elf == NULL)
 905                 goto out_close;
 906
 907         if (gelf_getehdr(elf, &ehdr) == NULL)
 908                 goto out_elf_end;
 909
 910         scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
 911                                          ".dynsym", &dynsym_idx);
 912         if (scn_dynsym == NULL)
 913                 goto out_elf_end;
 914
 915         scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 916                                           ".rela.plt", NULL);
 917         if (scn_plt_rel == NULL) {
 918                 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 919                                                   ".rel.plt", NULL);
 920                 if (scn_plt_rel == NULL)
 921                         goto out_elf_end;
 922         }
 923
 924         err = -1;
 925
 926         if (shdr_rel_plt.sh_link != dynsym_idx)
 927                 goto out_elf_end;
 928
 929         if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
 930                 goto out_elf_end;
 931
 932         /*
 933          * Fetch the relocation section to find the idxes to the GOT
 934          * and the symbols in the .dynsym they refer to.
 935          */
 936         reldata = elf_getdata(scn_plt_rel, NULL);
 937         if (reldata == NULL)
 938                 goto out_elf_end;
 939
 940         syms = elf_getdata(scn_dynsym, NULL);
 941         if (syms == NULL)
 942                 goto out_elf_end;
 943
 944         scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
 945         if (scn_symstrs == NULL)
 946                 goto out_elf_end;
 947
 948         symstrs = elf_getdata(scn_symstrs, NULL);
 949         if (symstrs == NULL)
 950                 goto out_elf_end;
 951
 952         nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
 953         plt_offset = shdr_plt.sh_offset;
 954
 955         if (shdr_rel_plt.sh_type == SHT_RELA) {
 956                 GElf_Rela pos_mem, *pos;
 957
 958                 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
 959                                            nr_rel_entries) {
 960                         symidx = GELF_R_SYM(pos->r_info);
 961                         plt_offset += shdr_plt.sh_entsize;
 962                         gelf_getsym(syms, symidx, &sym);
 963                         snprintf(sympltname, sizeof(sympltname),
 964                                  "%s@plt", elf_sym__name(&sym, symstrs));
 965
 966                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 967                                         STB_GLOBAL, sympltname);
 968                         if (!f)
 969                                 goto out_elf_end;
 970
 971                         if (filter && filter(map, f))
 972                                 symbol__delete(f);
 973                         else {
 974                                 symbols__insert(&dso->symbols[map->type], f);
 975                                 ++nr;
 976                         }
 977                 }
 978         } else if (shdr_rel_plt.sh_type == SHT_REL) {
 979                 GElf_Rel pos_mem, *pos;
 980                 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
 981                                           nr_rel_entries) {
 982                         symidx = GELF_R_SYM(pos->r_info);
 983                         plt_offset += shdr_plt.sh_entsize;
 984                         gelf_getsym(syms, symidx, &sym);
 985                         snprintf(sympltname, sizeof(sympltname),
 986                                  "%s@plt", elf_sym__name(&sym, symstrs));
 987
 988                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 989                                         STB_GLOBAL, sympltname);
 990                         if (!f)
 991                                 goto out_elf_end;
 992
 993                         if (filter && filter(map, f))
 994                                 symbol__delete(f);
 995                         else {
 996                                 symbols__insert(&dso->symbols[map->type], f);
 997                                 ++nr;
 998                         }
 999                 }
1000         }
1001
1002         err = 0;
1003 out_elf_end:
1004         elf_end(elf);
1005 out_close:
1006         close(fd);
1007
1008         if (err == 0)
1009                 return nr;
1010 out:
1011         pr_debug("%s: problems reading %s PLT info.\n",
1012                  __func__, dso->long_name);
1013         return 0;
1014 }
1015
1016 static bool elf_sym__is_a(GElf_Sym *sym, enum map_type type)
1017 {
1018         switch (type) {
1019         case MAP__FUNCTION:
1020                 return elf_sym__is_function(sym);
1021         case MAP__VARIABLE:
1022                 return elf_sym__is_object(sym);
1023         default:
1024                 return false;
1025         }
1026 }
1027
1028 static bool elf_sec__is_a(GElf_Shdr *shdr, Elf_Data *secstrs,
1029                           enum map_type type)
1030 {
1031         switch (type) {
1032         case MAP__FUNCTION:
1033                 return elf_sec__is_text(shdr, secstrs);
1034         case MAP__VARIABLE:
1035                 return elf_sec__is_data(shdr, secstrs);
1036         default:
1037                 return false;
1038         }
1039 }
1040
1041 static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
1042 {
1043         Elf_Scn *sec = NULL;
1044         GElf_Shdr shdr;
1045         size_t cnt = 1;
1046
1047         while ((sec = elf_nextscn(elf, sec)) != NULL) {
1048                 gelf_getshdr(sec, &shdr);
1049
1050                 if ((addr >= shdr.sh_addr) &&
1051                     (addr < (shdr.sh_addr + shdr.sh_size)))
1052                         return cnt;
1053
1054                 ++cnt;
1055         }
1056
1057         return -1;
1058 }
1059
1060 static int dso__load_sym(struct dso *dso, struct map *map, const char *name,
1061                          int fd, symbol_filter_t filter, int kmodule,
1062                          int want_symtab)
1063 {
1064         struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL;
1065         struct map *curr_map = map;
1066         struct dso *curr_dso = dso;
1067         Elf_Data *symstrs, *secstrs;
1068         uint32_t nr_syms;
1069         int err = -1;
1070         uint32_t idx;
1071         GElf_Ehdr ehdr;
1072         GElf_Shdr shdr, opdshdr;
1073         Elf_Data *syms, *opddata = NULL;
1074         GElf_Sym sym;
1075         Elf_Scn *sec, *sec_strndx, *opdsec;
1076         Elf *elf;
1077         int nr = 0;
1078         size_t opdidx = 0;
1079
1080         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1081         if (elf == NULL) {
1082                 pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
1083                 goto out_close;
1084         }
1085
1086         if (gelf_getehdr(elf, &ehdr) == NULL) {
1087                 pr_debug("%s: cannot get elf header.\n", __func__);
1088                 goto out_elf_end;
1089         }
1090
1091         /* Always reject images with a mismatched build-id: */
1092         if (dso->has_build_id) {
1093                 u8 build_id[BUILD_ID_SIZE];
1094
1095                 if (elf_read_build_id(elf, build_id,
1096                                       BUILD_ID_SIZE) != BUILD_ID_SIZE)
1097                         goto out_elf_end;
1098
1099                 if (!dso__build_id_equal(dso, build_id))
1100                         goto out_elf_end;
1101         }
1102
1103         sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
1104         if (sec == NULL) {
1105                 if (want_symtab)
1106                         goto out_elf_end;
1107
1108                 sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
1109                 if (sec == NULL)
1110                         goto out_elf_end;
1111         }
1112
1113         opdsec = elf_section_by_name(elf, &ehdr, &opdshdr, ".opd", &opdidx);
1114         if (opdsec)
1115                 opddata = elf_rawdata(opdsec, NULL);
1116
1117         syms = elf_getdata(sec, NULL);
1118         if (syms == NULL)
1119                 goto out_elf_end;
1120
1121         sec = elf_getscn(elf, shdr.sh_link);
1122         if (sec == NULL)
1123                 goto out_elf_end;
1124
1125         symstrs = elf_getdata(sec, NULL);
1126         if (symstrs == NULL)
1127                 goto out_elf_end;
1128
1129         sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
1130         if (sec_strndx == NULL)
1131                 goto out_elf_end;
1132
1133         secstrs = elf_getdata(sec_strndx, NULL);
1134         if (secstrs == NULL)
1135                 goto out_elf_end;
1136
1137         nr_syms = shdr.sh_size / shdr.sh_entsize;
1138
1139         memset(&sym, 0, sizeof(sym));
1140         if (dso->kernel == DSO_TYPE_USER) {
1141                 dso->adjust_symbols = (ehdr.e_type == ET_EXEC ||
1142                                 elf_section_by_name(elf, &ehdr, &shdr,
1143                                                      ".gnu.prelink_undo",
1144                                                      NULL) != NULL);
1145         } else {
1146                 dso->adjust_symbols = 0;
1147         }
1148         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
1149                 struct symbol *f;
1150                 const char *elf_name = elf_sym__name(&sym, symstrs);
1151                 char *demangled = NULL;
1152                 int is_label = elf_sym__is_label(&sym);
1153                 const char *section_name;
1154
1155                 if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
1156                     strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
1157                         kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
1158
1159                 if (!is_label && !elf_sym__is_a(&sym, map->type))
1160                         continue;
1161
1162                 /* Reject ARM ELF "mapping symbols": these aren't unique and
1163                  * don't identify functions, so will confuse the profile
1164                  * output: */
1165                 if (ehdr.e_machine == EM_ARM) {
1166                         if (!strcmp(elf_name, "$a") ||
1167                             !strcmp(elf_name, "$d") ||
1168                             !strcmp(elf_name, "$t"))
1169                                 continue;
1170                 }
1171
1172                 if (opdsec && sym.st_shndx == opdidx) {
1173                         u32 offset = sym.st_value - opdshdr.sh_addr;
1174                         u64 *opd = opddata->d_buf + offset;
1175                         sym.st_value = *opd;
1176                         sym.st_shndx = elf_addr_to_index(elf, sym.st_value);
1177                 }
1178
1179                 sec = elf_getscn(elf, sym.st_shndx);
1180                 if (!sec)
1181                         goto out_elf_end;
1182
1183                 gelf_getshdr(sec, &shdr);
1184
1185                 if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
1186                         continue;
1187
1188                 section_name = elf_sec__name(&shdr, secstrs);
1189
1190                 /* On ARM, symbols for thumb functions have 1 added to
1191                  * the symbol address as a flag - remove it */
1192                 if ((ehdr.e_machine == EM_ARM) &&
1193                     (map->type == MAP__FUNCTION) &&
1194                     (sym.st_value & 1))
1195                         --sym.st_value;
1196
1197                 if (dso->kernel != DSO_TYPE_USER || kmodule) {
1198                         char dso_name[PATH_MAX];
1199
1200                         if (strcmp(section_name,
1201                                    (curr_dso->short_name +
1202                                     dso->short_name_len)) == 0)
1203                                 goto new_symbol;
1204
1205                         if (strcmp(section_name, ".text") == 0) {
1206                                 curr_map = map;
1207                                 curr_dso = dso;
1208                                 goto new_symbol;
1209                         }
1210
1211                         snprintf(dso_name, sizeof(dso_name),
1212                                  "%s%s", dso->short_name, section_name);
1213
1214                         curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name);
1215                         if (curr_map == NULL) {
1216                                 u64 start = sym.st_value;
1217
1218                                 if (kmodule)
1219                                         start += map->start + shdr.sh_offset;
1220
1221                                 curr_dso = dso__new(dso_name);
1222                                 if (curr_dso == NULL)
1223                                         goto out_elf_end;
1224                                 curr_dso->kernel = dso->kernel;
1225                                 curr_dso->long_name = dso->long_name;
1226                                 curr_dso->long_name_len = dso->long_name_len;
1227                                 curr_map = map__new2(start, curr_dso,
1228                                                      map->type);
1229                                 if (curr_map == NULL) {
1230                                         dso__delete(curr_dso);
1231                                         goto out_elf_end;
1232                                 }
1233                                 curr_map->map_ip = identity__map_ip;
1234                                 curr_map->unmap_ip = identity__map_ip;
1235                                 curr_dso->symtab_type = dso->symtab_type;
1236                                 map_groups__insert(kmap->kmaps, curr_map);
1237                                 dsos__add(&dso->node, curr_dso);
1238                                 dso__set_loaded(curr_dso, map->type);
1239                         } else
1240                                 curr_dso = curr_map->dso;
1241
1242                         goto new_symbol;
1243                 }
1244
1245                 if (curr_dso->adjust_symbols) {
1246                         pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " "
1247                                   "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__,
1248                                   (u64)sym.st_value, (u64)shdr.sh_addr,
1249                                   (u64)shdr.sh_offset);
1250                         sym.st_value -= shdr.sh_addr - shdr.sh_offset;
1251                 }
1252                 /*
1253                  * We need to figure out if the object was created from C++ sources
1254                  * DWARF DW_compile_unit has this, but we don't always have access
1255                  * to it...
1256                  */
1257                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
1258                 if (demangled != NULL)
1259                         elf_name = demangled;
1260 new_symbol:
1261                 f = symbol__new(sym.st_value, sym.st_size,
1262                                 GELF_ST_BIND(sym.st_info), elf_name);
1263                 free(demangled);
1264                 if (!f)
1265                         goto out_elf_end;
1266
1267                 if (filter && filter(curr_map, f))
1268                         symbol__delete(f);
1269                 else {
1270                         symbols__insert(&curr_dso->symbols[curr_map->type], f);
1271                         nr++;
1272                 }
1273         }
1274
1275         /*
1276          * For misannotated, zeroed, ASM function sizes.
1277          */
1278         if (nr > 0) {
1279                 symbols__fixup_end(&dso->symbols[map->type]);
1280                 if (kmap) {
1281                         /*
1282                          * We need to fixup this here too because we create new
1283                          * maps here, for things like vsyscall sections.
1284                          */
1285                         __map_groups__fixup_end(kmap->kmaps, map->type);
1286                 }
1287         }
1288         err = nr;
1289 out_elf_end:
1290         elf_end(elf);
1291 out_close:
1292         return err;
1293 }
1294
1295 static bool dso__build_id_equal(const struct dso *dso, u8 *build_id)
1296 {
1297         return memcmp(dso->build_id, build_id, sizeof(dso->build_id)) == 0;
1298 }
1299
1300 bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
1301 {
1302         bool have_build_id = false;
1303         struct dso *pos;
1304
1305         list_for_each_entry(pos, head, node) {
1306                 if (with_hits && !pos->hit)
1307                         continue;
1308                 if (pos->has_build_id) {
1309                         have_build_id = true;
1310                         continue;
1311                 }
1312                 if (filename__read_build_id(pos->long_name, pos->build_id,
1313                                             sizeof(pos->build_id)) > 0) {
1314                         have_build_id     = true;
1315                         pos->has_build_id = true;
1316                 }
1317         }
1318
1319         return have_build_id;
1320 }
1321
1322 /*
1323  * Align offset to 4 bytes as needed for note name and descriptor data.
1324  */
1325 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
1326
1327 static int elf_read_build_id(Elf *elf, void *bf, size_t size)
1328 {
1329         int err = -1;
1330         GElf_Ehdr ehdr;
1331         GElf_Shdr shdr;
1332         Elf_Data *data;
1333         Elf_Scn *sec;
1334         Elf_Kind ek;
1335         void *ptr;
1336
1337         if (size < BUILD_ID_SIZE)
1338                 goto out;
1339
1340         ek = elf_kind(elf);
1341         if (ek != ELF_K_ELF)
1342                 goto out;
1343
1344         if (gelf_getehdr(elf, &ehdr) == NULL) {
1345                 pr_err("%s: cannot get elf header.\n", __func__);
1346                 goto out;
1347         }
1348
1349         sec = elf_section_by_name(elf, &ehdr, &shdr,
1350                                   ".note.gnu.build-id", NULL);
1351         if (sec == NULL) {
1352                 sec = elf_section_by_name(elf, &ehdr, &shdr,
1353                                           ".notes", NULL);
1354                 if (sec == NULL)
1355                         goto out;
1356         }
1357
1358         data = elf_getdata(sec, NULL);
1359         if (data == NULL)
1360                 goto out;
1361
1362         ptr = data->d_buf;
1363         while (ptr < (data->d_buf + data->d_size)) {
1364                 GElf_Nhdr *nhdr = ptr;
1365                 int namesz = NOTE_ALIGN(nhdr->n_namesz),
1366                     descsz = NOTE_ALIGN(nhdr->n_descsz);
1367                 const char *name;
1368
1369                 ptr += sizeof(*nhdr);
1370                 name = ptr;
1371                 ptr += namesz;
1372                 if (nhdr->n_type == NT_GNU_BUILD_ID &&
1373                     nhdr->n_namesz == sizeof("GNU")) {
1374                         if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
1375                                 memcpy(bf, ptr, BUILD_ID_SIZE);
1376                                 err = BUILD_ID_SIZE;
1377                                 break;
1378                         }
1379                 }
1380                 ptr += descsz;
1381         }
1382
1383 out:
1384         return err;
1385 }
1386
1387 int filename__read_build_id(const char *filename, void *bf, size_t size)
1388 {
1389         int fd, err = -1;
1390         Elf *elf;
1391
1392         if (size < BUILD_ID_SIZE)
1393                 goto out;
1394
1395         fd = open(filename, O_RDONLY);
1396         if (fd < 0)
1397                 goto out;
1398
1399         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1400         if (elf == NULL) {
1401                 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
1402                 goto out_close;
1403         }
1404
1405         err = elf_read_build_id(elf, bf, size);
1406
1407         elf_end(elf);
1408 out_close:
1409         close(fd);
1410 out:
1411         return err;
1412 }
1413
1414 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
1415 {
1416         int fd, err = -1;
1417
1418         if (size < BUILD_ID_SIZE)
1419                 goto out;
1420
1421         fd = open(filename, O_RDONLY);
1422         if (fd < 0)
1423                 goto out;
1424
1425         while (1) {
1426                 char bf[BUFSIZ];
1427                 GElf_Nhdr nhdr;
1428                 int namesz, descsz;
1429
1430                 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
1431                         break;
1432
1433                 namesz = NOTE_ALIGN(nhdr.n_namesz);
1434                 descsz = NOTE_ALIGN(nhdr.n_descsz);
1435                 if (nhdr.n_type == NT_GNU_BUILD_ID &&
1436                     nhdr.n_namesz == sizeof("GNU")) {
1437                         if (read(fd, bf, namesz) != namesz)
1438                                 break;
1439                         if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
1440                                 if (read(fd, build_id,
1441                                     BUILD_ID_SIZE) == BUILD_ID_SIZE) {
1442                                         err = 0;
1443                                         break;
1444                                 }
1445                         } else if (read(fd, bf, descsz) != descsz)
1446                                 break;
1447                 } else {
1448                         int n = namesz + descsz;
1449                         if (read(fd, bf, n) != n)
1450                                 break;
1451                 }
1452         }
1453         close(fd);
1454 out:
1455         return err;
1456 }
1457
1458 char dso__symtab_origin(const struct dso *dso)
1459 {
1460         static const char origin[] = {
1461                 [SYMTAB__KALLSYMS]            = 'k',
1462                 [SYMTAB__JAVA_JIT]            = 'j',
1463                 [SYMTAB__BUILD_ID_CACHE]      = 'B',
1464                 [SYMTAB__FEDORA_DEBUGINFO]    = 'f',
1465                 [SYMTAB__UBUNTU_DEBUGINFO]    = 'u',
1466                 [SYMTAB__BUILDID_DEBUGINFO]   = 'b',
1467                 [SYMTAB__SYSTEM_PATH_DSO]     = 'd',
1468                 [SYMTAB__SYSTEM_PATH_KMODULE] = 'K',
1469                 [SYMTAB__GUEST_KALLSYMS]      =  'g',
1470                 [SYMTAB__GUEST_KMODULE]       =  'G',
1471         };
1472
1473         if (dso == NULL || dso->symtab_type == SYMTAB__NOT_FOUND)
1474                 return '!';
1475         return origin[dso->symtab_type];
1476 }
1477
1478 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1479 {
1480         int size = PATH_MAX;
1481         char *name;
1482         int ret = -1;
1483         int fd;
1484         struct machine *machine;
1485         const char *root_dir;
1486         int want_symtab;
1487
1488         dso__set_loaded(dso, map->type);
1489
1490         if (dso->kernel == DSO_TYPE_KERNEL)
1491                 return dso__load_kernel_sym(dso, map, filter);
1492         else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1493                 return dso__load_guest_kernel_sym(dso, map, filter);
1494
1495         if (map->groups && map->groups->machine)
1496                 machine = map->groups->machine;
1497         else
1498                 machine = NULL;
1499
1500         name = malloc(size);
1501         if (!name)
1502                 return -1;
1503
1504         dso->adjust_symbols = 0;
1505
1506         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1507                 struct stat st;
1508
1509                 if (stat(dso->name, &st) < 0)
1510                         return -1;
1511
1512                 if (st.st_uid && (st.st_uid != geteuid())) {
1513                         pr_warning("File %s not owned by current user or root, "
1514                                 "ignoring it.\n", dso->name);
1515                         return -1;
1516                 }
1517
1518                 ret = dso__load_perf_map(dso, map, filter);
1519                 dso->symtab_type = ret > 0 ? SYMTAB__JAVA_JIT :
1520                                               SYMTAB__NOT_FOUND;
1521                 return ret;
1522         }
1523
1524         /* Iterate over candidate debug images.
1525          * On the first pass, only load images if they have a full symtab.
1526          * Failing that, do a second pass where we accept .dynsym also
1527          */
1528         want_symtab = 1;
1529 restart:
1530         for (dso->symtab_type = SYMTAB__BUILD_ID_CACHE;
1531              dso->symtab_type != SYMTAB__NOT_FOUND;
1532              dso->symtab_type++) {
1533                 switch (dso->symtab_type) {
1534                 case SYMTAB__BUILD_ID_CACHE:
1535                         /* skip the locally configured cache if a symfs is given */
1536                         if (symbol_conf.symfs[0] ||
1537                             (dso__build_id_filename(dso, name, size) == NULL)) {
1538                                 continue;
1539                         }
1540                         break;
1541                 case SYMTAB__FEDORA_DEBUGINFO:
1542                         snprintf(name, size, "%s/usr/lib/debug%s.debug",
1543                                  symbol_conf.symfs, dso->long_name);
1544                         break;
1545                 case SYMTAB__UBUNTU_DEBUGINFO:
1546                         snprintf(name, size, "%s/usr/lib/debug%s",
1547                                  symbol_conf.symfs, dso->long_name);
1548                         break;
1549                 case SYMTAB__BUILDID_DEBUGINFO: {
1550                         char build_id_hex[BUILD_ID_SIZE * 2 + 1];
1551
1552                         if (!dso->has_build_id)
1553                                 continue;
1554
1555                         build_id__sprintf(dso->build_id,
1556                                           sizeof(dso->build_id),
1557                                           build_id_hex);
1558                         snprintf(name, size,
1559                                  "%s/usr/lib/debug/.build-id/%.2s/%s.debug",
1560                                  symbol_conf.symfs, build_id_hex, build_id_hex + 2);
1561                         }
1562                         break;
1563                 case SYMTAB__SYSTEM_PATH_DSO:
1564                         snprintf(name, size, "%s%s",
1565                              symbol_conf.symfs, dso->long_name);
1566                         break;
1567                 case SYMTAB__GUEST_KMODULE:
1568                         if (map->groups && machine)
1569                                 root_dir = machine->root_dir;
1570                         else
1571                                 root_dir = "";
1572                         snprintf(name, size, "%s%s%s", symbol_conf.symfs,
1573                                  root_dir, dso->long_name);
1574                         break;
1575
1576                 case SYMTAB__SYSTEM_PATH_KMODULE:
1577                         snprintf(name, size, "%s%s", symbol_conf.symfs,
1578                                  dso->long_name);
1579                         break;
1580                 default:;
1581                 }
1582
1583                 /* Name is now the name of the next image to try */
1584                 fd = open(name, O_RDONLY);
1585                 if (fd < 0)
1586                         continue;
1587
1588                 ret = dso__load_sym(dso, map, name, fd, filter, 0,
1589                                     want_symtab);
1590                 close(fd);
1591
1592                 /*
1593                  * Some people seem to have debuginfo files _WITHOUT_ debug
1594                  * info!?!?
1595                  */
1596                 if (!ret)
1597                         continue;
1598
1599                 if (ret > 0) {
1600                         int nr_plt = dso__synthesize_plt_symbols(dso, map,
1601                                                                  filter);
1602                         if (nr_plt > 0)
1603                                 ret += nr_plt;
1604                         break;
1605                 }
1606         }
1607
1608         /*
1609          * If we wanted a full symtab but no image had one,
1610          * relax our requirements and repeat the search.
1611          */
1612         if (ret <= 0 && want_symtab) {
1613                 want_symtab = 0;
1614                 goto restart;
1615         }
1616
1617         free(name);
1618         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1619                 return 0;
1620         return ret;
1621 }
1622
1623 struct map *map_groups__find_by_name(struct map_groups *mg,
1624                                      enum map_type type, const char *name)
1625 {
1626         struct rb_node *nd;
1627
1628         for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
1629                 struct map *map = rb_entry(nd, struct map, rb_node);
1630
1631                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1632                         return map;
1633         }
1634
1635         return NULL;
1636 }
1637
1638 static int dso__kernel_module_get_build_id(struct dso *dso,
1639                                            const char *root_dir)
1640 {
1641         char filename[PATH_MAX];
1642         /*
1643          * kernel module short names are of the form "[module]" and
1644          * we need just "module" here.
1645          */
1646         const char *name = dso->short_name + 1;
1647
1648         snprintf(filename, sizeof(filename),
1649                  "%s/sys/module/%.*s/notes/.note.gnu.build-id",
1650                  root_dir, (int)strlen(name) - 1, name);
1651
1652         if (sysfs__read_build_id(filename, dso->build_id,
1653                                  sizeof(dso->build_id)) == 0)
1654                 dso->has_build_id = true;
1655
1656         return 0;
1657 }
1658
1659 static int map_groups__set_modules_path_dir(struct map_groups *mg,
1660                                 const char *dir_name)
1661 {
1662         struct dirent *dent;
1663         DIR *dir = opendir(dir_name);
1664         int ret = 0;
1665
1666         if (!dir) {
1667                 pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
1668                 return -1;
1669         }
1670
1671         while ((dent = readdir(dir)) != NULL) {
1672                 char path[PATH_MAX];
1673                 struct stat st;
1674
1675                 /*sshfs might return bad dent->d_type, so we have to stat*/
1676                 sprintf(path, "%s/%s", dir_name, dent->d_name);
1677                 if (stat(path, &st))
1678                         continue;
1679
1680                 if (S_ISDIR(st.st_mode)) {
1681                         if (!strcmp(dent->d_name, ".") ||
1682                             !strcmp(dent->d_name, ".."))
1683                                 continue;
1684
1685                         snprintf(path, sizeof(path), "%s/%s",
1686                                  dir_name, dent->d_name);
1687                         ret = map_groups__set_modules_path_dir(mg, path);
1688                         if (ret < 0)
1689                                 goto out;
1690                 } else {
1691                         char *dot = strrchr(dent->d_name, '.'),
1692                              dso_name[PATH_MAX];
1693                         struct map *map;
1694                         char *long_name;
1695
1696                         if (dot == NULL || strcmp(dot, ".ko"))
1697                                 continue;
1698                         snprintf(dso_name, sizeof(dso_name), "[%.*s]",
1699                                  (int)(dot - dent->d_name), dent->d_name);
1700
1701                         strxfrchar(dso_name, '-', '_');
1702                         map = map_groups__find_by_name(mg, MAP__FUNCTION,
1703                                                        dso_name);
1704                         if (map == NULL)
1705                                 continue;
1706
1707                         snprintf(path, sizeof(path), "%s/%s",
1708                                  dir_name, dent->d_name);
1709
1710                         long_name = strdup(path);
1711                         if (long_name == NULL) {
1712                                 ret = -1;
1713                                 goto out;
1714                         }
1715                         dso__set_long_name(map->dso, long_name);
1716                         map->dso->lname_alloc = 1;
1717                         dso__kernel_module_get_build_id(map->dso, "");
1718                 }
1719         }
1720
1721 out:
1722         closedir(dir);
1723         return ret;
1724 }
1725
1726 static char *get_kernel_version(const char *root_dir)
1727 {
1728         char version[PATH_MAX];
1729         FILE *file;
1730         char *name, *tmp;
1731         const char *prefix = "Linux version ";
1732
1733         sprintf(version, "%s/proc/version", root_dir);
1734         file = fopen(version, "r");
1735         if (!file)
1736                 return NULL;
1737
1738         version[0] = '\0';
1739         tmp = fgets(version, sizeof(version), file);
1740         fclose(file);
1741
1742         name = strstr(version, prefix);
1743         if (!name)
1744                 return NULL;
1745         name += strlen(prefix);
1746         tmp = strchr(name, ' ');
1747         if (tmp)
1748                 *tmp = '\0';
1749
1750         return strdup(name);
1751 }
1752
1753 static int machine__set_modules_path(struct machine *machine)
1754 {
1755         char *version;
1756         char modules_path[PATH_MAX];
1757
1758         version = get_kernel_version(machine->root_dir);
1759         if (!version)
1760                 return -1;
1761
1762         snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s/kernel",
1763                  machine->root_dir, version);
1764         free(version);
1765
1766         return map_groups__set_modules_path_dir(&machine->kmaps, modules_path);
1767 }
1768
1769 /*
1770  * Constructor variant for modules (where we know from /proc/modules where
1771  * they are loaded) and for vmlinux, where only after we load all the
1772  * symbols we'll know where it starts and ends.
1773  */
1774 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
1775 {
1776         struct map *map = calloc(1, (sizeof(*map) +
1777                                      (dso->kernel ? sizeof(struct kmap) : 0)));
1778         if (map != NULL) {
1779                 /*
1780                  * ->end will be filled after we load all the symbols
1781                  */
1782                 map__init(map, type, start, 0, 0, dso);
1783         }
1784
1785         return map;
1786 }
1787
1788 struct map *machine__new_module(struct machine *machine, u64 start,
1789                                 const char *filename)
1790 {
1791         struct map *map;
1792         struct dso *dso = __dsos__findnew(&machine->kernel_dsos, filename);
1793
1794         if (dso == NULL)
1795                 return NULL;
1796
1797         map = map__new2(start, dso, MAP__FUNCTION);
1798         if (map == NULL)
1799                 return NULL;
1800
1801         if (machine__is_host(machine))
1802                 dso->symtab_type = SYMTAB__SYSTEM_PATH_KMODULE;
1803         else
1804                 dso->symtab_type = SYMTAB__GUEST_KMODULE;
1805         map_groups__insert(&machine->kmaps, map);
1806         return map;
1807 }
1808
1809 static int machine__create_modules(struct machine *machine)
1810 {
1811         char *line = NULL;
1812         size_t n;
1813         FILE *file;
1814         struct map *map;
1815         const char *modules;
1816         char path[PATH_MAX];
1817
1818         if (machine__is_default_guest(machine))
1819                 modules = symbol_conf.default_guest_modules;
1820         else {
1821                 sprintf(path, "%s/proc/modules", machine->root_dir);
1822                 modules = path;
1823         }
1824
1825         if (symbol__restricted_filename(path, "/proc/modules"))
1826                 return -1;
1827
1828         file = fopen(modules, "r");
1829         if (file == NULL)
1830                 return -1;
1831
1832         while (!feof(file)) {
1833                 char name[PATH_MAX];
1834                 u64 start;
1835                 char *sep;
1836                 int line_len;
1837
1838                 line_len = getline(&line, &n, file);
1839                 if (line_len < 0)
1840                         break;
1841
1842                 if (!line)
1843                         goto out_failure;
1844
1845                 line[--line_len] = '\0'; /* \n */
1846
1847                 sep = strrchr(line, 'x');
1848                 if (sep == NULL)
1849                         continue;
1850
1851                 hex2u64(sep + 1, &start);
1852
1853                 sep = strchr(line, ' ');
1854                 if (sep == NULL)
1855                         continue;
1856
1857                 *sep = '\0';
1858
1859                 snprintf(name, sizeof(name), "[%s]", line);
1860                 map = machine__new_module(machine, start, name);
1861                 if (map == NULL)
1862                         goto out_delete_line;
1863                 dso__kernel_module_get_build_id(map->dso, machine->root_dir);
1864         }
1865
1866         free(line);
1867         fclose(file);
1868
1869         return machine__set_modules_path(machine);
1870
1871 out_delete_line:
1872         free(line);
1873 out_failure:
1874         return -1;
1875 }
1876
1877 int dso__load_vmlinux(struct dso *dso, struct map *map,
1878                       const char *vmlinux, symbol_filter_t filter)
1879 {
1880         int err = -1, fd;
1881         char symfs_vmlinux[PATH_MAX];
1882
1883         snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
1884                  symbol_conf.symfs, vmlinux);
1885         fd = open(symfs_vmlinux, O_RDONLY);
1886         if (fd < 0)
1887                 return -1;
1888
1889         dso__set_long_name(dso, (char *)vmlinux);
1890         dso__set_loaded(dso, map->type);
1891         err = dso__load_sym(dso, map, symfs_vmlinux, fd, filter, 0, 0);
1892         close(fd);
1893
1894         if (err > 0)
1895                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1896
1897         return err;
1898 }
1899
1900 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1901                            symbol_filter_t filter)
1902 {
1903         int i, err = 0;
1904         char *filename;
1905
1906         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1907                  vmlinux_path__nr_entries + 1);
1908
1909         filename = dso__build_id_filename(dso, NULL, 0);
1910         if (filename != NULL) {
1911                 err = dso__load_vmlinux(dso, map, filename, filter);
1912                 if (err > 0) {
1913                         dso__set_long_name(dso, filename);
1914                         goto out;
1915                 }
1916                 free(filename);
1917         }
1918
1919         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1920                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], filter);
1921                 if (err > 0) {
1922                         dso__set_long_name(dso, strdup(vmlinux_path[i]));
1923                         break;
1924                 }
1925         }
1926 out:
1927         return err;
1928 }
1929
1930 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1931                                 symbol_filter_t filter)
1932 {
1933         int err;
1934         const char *kallsyms_filename = NULL;
1935         char *kallsyms_allocated_filename = NULL;
1936         /*
1937          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1938          * it and only it, reporting errors to the user if it cannot be used.
1939          *
1940          * For instance, try to analyse an ARM perf.data file _without_ a
1941          * build-id, or if the user specifies the wrong path to the right
1942          * vmlinux file, obviously we can't fallback to another vmlinux (a
1943          * x86_86 one, on the machine where analysis is being performed, say),
1944          * or worse, /proc/kallsyms.
1945          *
1946          * If the specified file _has_ a build-id and there is a build-id
1947          * section in the perf.data file, we will still do the expected
1948          * validation in dso__load_vmlinux and will bail out if they don't
1949          * match.
1950          */
1951         if (symbol_conf.kallsyms_name != NULL) {
1952                 kallsyms_filename = symbol_conf.kallsyms_name;
1953                 goto do_kallsyms;
1954         }
1955
1956         if (symbol_conf.vmlinux_name != NULL) {
1957                 err = dso__load_vmlinux(dso, map,
1958                                         symbol_conf.vmlinux_name, filter);
1959                 if (err > 0) {
1960                         dso__set_long_name(dso,
1961                                            strdup(symbol_conf.vmlinux_name));
1962                         goto out_fixup;
1963                 }
1964                 return err;
1965         }
1966
1967         if (vmlinux_path != NULL) {
1968                 err = dso__load_vmlinux_path(dso, map, filter);
1969                 if (err > 0)
1970                         goto out_fixup;
1971         }
1972
1973         /* do not try local files if a symfs was given */
1974         if (symbol_conf.symfs[0] != 0)
1975                 return -1;
1976
1977         /*
1978          * Say the kernel DSO was created when processing the build-id header table,
1979          * we have a build-id, so check if it is the same as the running kernel,
1980          * using it if it is.
1981          */
1982         if (dso->has_build_id) {
1983                 u8 kallsyms_build_id[BUILD_ID_SIZE];
1984                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1985
1986                 if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
1987                                          sizeof(kallsyms_build_id)) == 0) {
1988                         if (dso__build_id_equal(dso, kallsyms_build_id)) {
1989                                 kallsyms_filename = "/proc/kallsyms";
1990                                 goto do_kallsyms;
1991                         }
1992                 }
1993                 /*
1994                  * Now look if we have it on the build-id cache in
1995                  * $HOME/.debug/[kernel.kallsyms].
1996                  */
1997                 build_id__sprintf(dso->build_id, sizeof(dso->build_id),
1998                                   sbuild_id);
1999
2000                 if (asprintf(&kallsyms_allocated_filename,
2001                              "%s/.debug/[kernel.kallsyms]/%s",
2002                              getenv("HOME"), sbuild_id) == -1) {
2003                         pr_err("Not enough memory for kallsyms file lookup\n");
2004                         return -1;
2005                 }
2006
2007                 kallsyms_filename = kallsyms_allocated_filename;
2008
2009                 if (access(kallsyms_filename, F_OK)) {
2010                         pr_err("No kallsyms or vmlinux with build-id %s "
2011                                "was found\n", sbuild_id);
2012                         free(kallsyms_allocated_filename);
2013                         return -1;
2014                 }
2015         } else {
2016                 /*
2017                  * Last resort, if we don't have a build-id and couldn't find
2018                  * any vmlinux file, try the running kernel kallsyms table.
2019                  */
2020                 kallsyms_filename = "/proc/kallsyms";
2021         }
2022
2023 do_kallsyms:
2024         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
2025         if (err > 0)
2026                 pr_debug("Using %s for symbols\n", kallsyms_filename);
2027         free(kallsyms_allocated_filename);
2028
2029         if (err > 0) {
2030 out_fixup:
2031                 if (kallsyms_filename != NULL)
2032                         dso__set_long_name(dso, strdup("[kernel.kallsyms]"));
2033                 map__fixup_start(map);
2034                 map__fixup_end(map);
2035         }
2036
2037         return err;
2038 }
2039
2040 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
2041                                       symbol_filter_t filter)
2042 {
2043         int err;
2044         const char *kallsyms_filename = NULL;
2045         struct machine *machine;
2046         char path[PATH_MAX];
2047
2048         if (!map->groups) {
2049                 pr_debug("Guest kernel map hasn't the point to groups\n");
2050                 return -1;
2051         }
2052         machine = map->groups->machine;
2053
2054         if (machine__is_default_guest(machine)) {
2055                 /*
2056                  * if the user specified a vmlinux filename, use it and only
2057                  * it, reporting errors to the user if it cannot be used.
2058                  * Or use file guest_kallsyms inputted by user on commandline
2059                  */
2060                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
2061                         err = dso__load_vmlinux(dso, map,
2062                                 symbol_conf.default_guest_vmlinux_name, filter);
2063                         goto out_try_fixup;
2064                 }
2065
2066                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
2067                 if (!kallsyms_filename)
2068                         return -1;
2069         } else {
2070                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2071                 kallsyms_filename = path;
2072         }
2073
2074         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
2075         if (err > 0)
2076                 pr_debug("Using %s for symbols\n", kallsyms_filename);
2077
2078 out_try_fixup:
2079         if (err > 0) {
2080                 if (kallsyms_filename != NULL) {
2081                         machine__mmap_name(machine, path, sizeof(path));
2082                         dso__set_long_name(dso, strdup(path));
2083                 }
2084                 map__fixup_start(map);
2085                 map__fixup_end(map);
2086         }
2087
2088         return err;
2089 }
2090
2091 static void dsos__add(struct list_head *head, struct dso *dso)
2092 {
2093         list_add_tail(&dso->node, head);
2094 }
2095
2096 static struct dso *dsos__find(struct list_head *head, const char *name)
2097 {
2098         struct dso *pos;
2099
2100         list_for_each_entry(pos, head, node)
2101                 if (strcmp(pos->long_name, name) == 0)
2102                         return pos;
2103         return NULL;
2104 }
2105
2106 struct dso *__dsos__findnew(struct list_head *head, const char *name)
2107 {
2108         struct dso *dso = dsos__find(head, name);
2109
2110         if (!dso) {
2111                 dso = dso__new(name);
2112                 if (dso != NULL) {
2113                         dsos__add(head, dso);
2114                         dso__set_basename(dso);
2115                 }
2116         }
2117
2118         return dso;
2119 }
2120
2121 size_t __dsos__fprintf(struct list_head *head, FILE *fp)
2122 {
2123         struct dso *pos;
2124         size_t ret = 0;
2125
2126         list_for_each_entry(pos, head, node) {
2127                 int i;
2128                 for (i = 0; i < MAP__NR_TYPES; ++i)
2129                         ret += dso__fprintf(pos, i, fp);
2130         }
2131
2132         return ret;
2133 }
2134
2135 size_t machines__fprintf_dsos(struct rb_root *machines, FILE *fp)
2136 {
2137         struct rb_node *nd;
2138         size_t ret = 0;
2139
2140         for (nd = rb_first(machines); nd; nd = rb_next(nd)) {
2141                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
2142                 ret += __dsos__fprintf(&pos->kernel_dsos, fp);
2143                 ret += __dsos__fprintf(&pos->user_dsos, fp);
2144         }
2145
2146         return ret;
2147 }
2148
2149 static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
2150                                       bool with_hits)
2151 {
2152         struct dso *pos;
2153         size_t ret = 0;
2154
2155         list_for_each_entry(pos, head, node) {
2156                 if (with_hits && !pos->hit)
2157                         continue;
2158                 ret += dso__fprintf_buildid(pos, fp);
2159                 ret += fprintf(fp, " %s\n", pos->long_name);
2160         }
2161         return ret;
2162 }
2163
2164 size_t machine__fprintf_dsos_buildid(struct machine *machine, FILE *fp,
2165                                      bool with_hits)
2166 {
2167         return __dsos__fprintf_buildid(&machine->kernel_dsos, fp, with_hits) +
2168                __dsos__fprintf_buildid(&machine->user_dsos, fp, with_hits);
2169 }
2170
2171 size_t machines__fprintf_dsos_buildid(struct rb_root *machines,
2172                                       FILE *fp, bool with_hits)
2173 {
2174         struct rb_node *nd;
2175         size_t ret = 0;
2176
2177         for (nd = rb_first(machines); nd; nd = rb_next(nd)) {
2178                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
2179                 ret += machine__fprintf_dsos_buildid(pos, fp, with_hits);
2180         }
2181         return ret;
2182 }
2183
2184 struct dso *dso__new_kernel(const char *name)
2185 {
2186         struct dso *dso = dso__new(name ?: "[kernel.kallsyms]");
2187
2188         if (dso != NULL) {
2189                 dso__set_short_name(dso, "[kernel]");
2190                 dso->kernel = DSO_TYPE_KERNEL;
2191         }
2192
2193         return dso;
2194 }
2195
2196 static struct dso *dso__new_guest_kernel(struct machine *machine,
2197                                         const char *name)
2198 {
2199         char bf[PATH_MAX];
2200         struct dso *dso = dso__new(name ?: machine__mmap_name(machine, bf,
2201                                                               sizeof(bf)));
2202         if (dso != NULL) {
2203                 dso__set_short_name(dso, "[guest.kernel]");
2204                 dso->kernel = DSO_TYPE_GUEST_KERNEL;
2205         }
2206
2207         return dso;
2208 }
2209
2210 void dso__read_running_kernel_build_id(struct dso *dso, struct machine *machine)
2211 {
2212         char path[PATH_MAX];
2213
2214         if (machine__is_default_guest(machine))
2215                 return;
2216         sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
2217         if (sysfs__read_build_id(path, dso->build_id,
2218                                  sizeof(dso->build_id)) == 0)
2219                 dso->has_build_id = true;
2220 }
2221
2222 static struct dso *machine__create_kernel(struct machine *machine)
2223 {
2224         const char *vmlinux_name = NULL;
2225         struct dso *kernel;
2226
2227         if (machine__is_host(machine)) {
2228                 vmlinux_name = symbol_conf.vmlinux_name;
2229                 kernel = dso__new_kernel(vmlinux_name);
2230         } else {
2231                 if (machine__is_default_guest(machine))
2232                         vmlinux_name = symbol_conf.default_guest_vmlinux_name;
2233                 kernel = dso__new_guest_kernel(machine, vmlinux_name);
2234         }
2235
2236         if (kernel != NULL) {
2237                 dso__read_running_kernel_build_id(kernel, machine);
2238                 dsos__add(&machine->kernel_dsos, kernel);
2239         }
2240         return kernel;
2241 }
2242
2243 struct process_args {
2244         u64 start;
2245 };
2246
2247 static int symbol__in_kernel(void *arg, const char *name,
2248                              char type __used, u64 start, u64 end __used)
2249 {
2250         struct process_args *args = arg;
2251
2252         if (strchr(name, '['))
2253                 return 0;
2254
2255         args->start = start;
2256         return 1;
2257 }
2258
2259 /* Figure out the start address of kernel map from /proc/kallsyms */
2260 static u64 machine__get_kernel_start_addr(struct machine *machine)
2261 {
2262         const char *filename;
2263         char path[PATH_MAX];
2264         struct process_args args;
2265
2266         if (machine__is_host(machine)) {
2267                 filename = "/proc/kallsyms";
2268         } else {
2269                 if (machine__is_default_guest(machine))
2270                         filename = (char *)symbol_conf.default_guest_kallsyms;
2271                 else {
2272                         sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2273                         filename = path;
2274                 }
2275         }
2276
2277         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
2278                 return 0;
2279
2280         if (kallsyms__parse(filename, &args, symbol__in_kernel) <= 0)
2281                 return 0;
2282
2283         return args.start;
2284 }
2285
2286 int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
2287 {
2288         enum map_type type;
2289         u64 start = machine__get_kernel_start_addr(machine);
2290
2291         for (type = 0; type < MAP__NR_TYPES; ++type) {
2292                 struct kmap *kmap;
2293
2294                 machine->vmlinux_maps[type] = map__new2(start, kernel, type);
2295                 if (machine->vmlinux_maps[type] == NULL)
2296                         return -1;
2297
2298                 machine->vmlinux_maps[type]->map_ip =
2299                         machine->vmlinux_maps[type]->unmap_ip =
2300                                 identity__map_ip;
2301                 kmap = map__kmap(machine->vmlinux_maps[type]);
2302                 kmap->kmaps = &machine->kmaps;
2303                 map_groups__insert(&machine->kmaps,
2304                                    machine->vmlinux_maps[type]);
2305         }
2306
2307         return 0;
2308 }
2309
2310 void machine__destroy_kernel_maps(struct machine *machine)
2311 {
2312         enum map_type type;
2313
2314         for (type = 0; type < MAP__NR_TYPES; ++type) {
2315                 struct kmap *kmap;
2316
2317                 if (machine->vmlinux_maps[type] == NULL)
2318                         continue;
2319
2320                 kmap = map__kmap(machine->vmlinux_maps[type]);
2321                 map_groups__remove(&machine->kmaps,
2322                                    machine->vmlinux_maps[type]);
2323                 if (kmap->ref_reloc_sym) {
2324                         /*
2325                          * ref_reloc_sym is shared among all maps, so free just
2326                          * on one of them.
2327                          */
2328                         if (type == MAP__FUNCTION) {
2329                                 free((char *)kmap->ref_reloc_sym->name);
2330                                 kmap->ref_reloc_sym->name = NULL;
2331                                 free(kmap->ref_reloc_sym);
2332                         }
2333                         kmap->ref_reloc_sym = NULL;
2334                 }
2335
2336                 map__delete(machine->vmlinux_maps[type]);
2337                 machine->vmlinux_maps[type] = NULL;
2338         }
2339 }
2340
2341 int machine__create_kernel_maps(struct machine *machine)
2342 {
2343         struct dso *kernel = machine__create_kernel(machine);
2344
2345         if (kernel == NULL ||
2346             __machine__create_kernel_maps(machine, kernel) < 0)
2347                 return -1;
2348
2349         if (symbol_conf.use_modules && machine__create_modules(machine) < 0)
2350                 pr_debug("Problems creating module maps, continuing anyway...\n");
2351         /*
2352          * Now that we have all the maps created, just set the ->end of them:
2353          */
2354         map_groups__fixup_end(&machine->kmaps);
2355         return 0;
2356 }
2357
2358 static void vmlinux_path__exit(void)
2359 {
2360         while (--vmlinux_path__nr_entries >= 0) {
2361                 free(vmlinux_path[vmlinux_path__nr_entries]);
2362                 vmlinux_path[vmlinux_path__nr_entries] = NULL;
2363         }
2364
2365         free(vmlinux_path);
2366         vmlinux_path = NULL;
2367 }
2368
2369 static int vmlinux_path__init(void)
2370 {
2371         struct utsname uts;
2372         char bf[PATH_MAX];
2373
2374         vmlinux_path = malloc(sizeof(char *) * 5);
2375         if (vmlinux_path == NULL)
2376                 return -1;
2377
2378         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
2379         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2380                 goto out_fail;
2381         ++vmlinux_path__nr_entries;
2382         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
2383         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2384                 goto out_fail;
2385         ++vmlinux_path__nr_entries;
2386
2387         /* only try running kernel version if no symfs was given */
2388         if (symbol_conf.symfs[0] != 0)
2389                 return 0;
2390
2391         if (uname(&uts) < 0)
2392                 return -1;
2393
2394         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
2395         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2396         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2397                 goto out_fail;
2398         ++vmlinux_path__nr_entries;
2399         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
2400         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2401         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2402                 goto out_fail;
2403         ++vmlinux_path__nr_entries;
2404         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
2405                  uts.release);
2406         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2407         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2408                 goto out_fail;
2409         ++vmlinux_path__nr_entries;
2410
2411         return 0;
2412
2413 out_fail:
2414         vmlinux_path__exit();
2415         return -1;
2416 }
2417
2418 size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp)
2419 {
2420         int i;
2421         size_t printed = 0;
2422         struct dso *kdso = machine->vmlinux_maps[MAP__FUNCTION]->dso;
2423
2424         if (kdso->has_build_id) {
2425                 char filename[PATH_MAX];
2426                 if (dso__build_id_filename(kdso, filename, sizeof(filename)))
2427                         printed += fprintf(fp, "[0] %s\n", filename);
2428         }
2429
2430         for (i = 0; i < vmlinux_path__nr_entries; ++i)
2431                 printed += fprintf(fp, "[%d] %s\n",
2432                                    i + kdso->has_build_id, vmlinux_path[i]);
2433
2434         return printed;
2435 }
2436
2437 static int setup_list(struct strlist **list, const char *list_str,
2438                       const char *list_name)
2439 {
2440         if (list_str == NULL)
2441                 return 0;
2442
2443         *list = strlist__new(true, list_str);
2444         if (!*list) {
2445                 pr_err("problems parsing %s list\n", list_name);
2446                 return -1;
2447         }
2448         return 0;
2449 }
2450
2451 static bool symbol__read_kptr_restrict(void)
2452 {
2453         bool value = false;
2454
2455         if (geteuid() != 0) {
2456                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2457                 if (fp != NULL) {
2458                         char line[8];
2459
2460                         if (fgets(line, sizeof(line), fp) != NULL)
2461                                 value = atoi(line) != 0;
2462
2463                         fclose(fp);
2464                 }
2465         }
2466
2467         return value;
2468 }
2469
2470 int symbol__init(void)
2471 {
2472         const char *symfs;
2473
2474         if (symbol_conf.initialized)
2475                 return 0;
2476
2477         symbol_conf.priv_size = ALIGN(symbol_conf.priv_size, sizeof(u64));
2478
2479         elf_version(EV_CURRENT);
2480         if (symbol_conf.sort_by_name)
2481                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2482                                           sizeof(struct symbol));
2483
2484         if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
2485                 return -1;
2486
2487         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2488                 pr_err("'.' is the only non valid --field-separator argument\n");
2489                 return -1;
2490         }
2491
2492         if (setup_list(&symbol_conf.dso_list,
2493                        symbol_conf.dso_list_str, "dso") < 0)
2494                 return -1;
2495
2496         if (setup_list(&symbol_conf.comm_list,
2497                        symbol_conf.comm_list_str, "comm") < 0)
2498                 goto out_free_dso_list;
2499
2500         if (setup_list(&symbol_conf.sym_list,
2501                        symbol_conf.sym_list_str, "symbol") < 0)
2502                 goto out_free_comm_list;
2503
2504         /*
2505          * A path to symbols of "/" is identical to ""
2506          * reset here for simplicity.
2507          */
2508         symfs = realpath(symbol_conf.symfs, NULL);
2509         if (symfs == NULL)
2510                 symfs = symbol_conf.symfs;
2511         if (strcmp(symfs, "/") == 0)
2512                 symbol_conf.symfs = "";
2513         if (symfs != symbol_conf.symfs)
2514                 free((void *)symfs);
2515
2516         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2517
2518         symbol_conf.initialized = true;
2519         return 0;
2520
2521 out_free_dso_list:
2522         strlist__delete(symbol_conf.dso_list);
2523 out_free_comm_list:
2524         strlist__delete(symbol_conf.comm_list);
2525         return -1;
2526 }
2527
2528 void symbol__exit(void)
2529 {
2530         if (!symbol_conf.initialized)
2531                 return;
2532         strlist__delete(symbol_conf.sym_list);
2533         strlist__delete(symbol_conf.dso_list);
2534         strlist__delete(symbol_conf.comm_list);
2535         vmlinux_path__exit();
2536         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2537         symbol_conf.initialized = false;
2538 }
2539
2540 int machines__create_kernel_maps(struct rb_root *machines, pid_t pid)
2541 {
2542         struct machine *machine = machines__findnew(machines, pid);
2543
2544         if (machine == NULL)
2545                 return -1;
2546
2547         return machine__create_kernel_maps(machine);
2548 }
2549
2550 static int hex(char ch)
2551 {
2552         if ((ch >= '0') && (ch <= '9'))
2553                 return ch - '0';
2554         if ((ch >= 'a') && (ch <= 'f'))
2555                 return ch - 'a' + 10;
2556         if ((ch >= 'A') && (ch <= 'F'))
2557                 return ch - 'A' + 10;
2558         return -1;
2559 }
2560
2561 /*
2562  * While we find nice hex chars, build a long_val.
2563  * Return number of chars processed.
2564  */
2565 int hex2u64(const char *ptr, u64 *long_val)
2566 {
2567         const char *p = ptr;
2568         *long_val = 0;
2569
2570         while (*p) {
2571                 const int hex_val = hex(*p);
2572
2573                 if (hex_val < 0)
2574                         break;
2575
2576                 *long_val = (*long_val << 4) | hex_val;
2577                 p++;
2578         }
2579
2580         return p - ptr;
2581 }
2582
2583 char *strxfrchar(char *s, char from, char to)
2584 {
2585         char *p = s;
2586
2587         while ((p = strchr(p, from)) != NULL)
2588                 *p++ = to;
2589
2590         return s;
2591 }
2592
2593 int machines__create_guest_kernel_maps(struct rb_root *machines)
2594 {
2595         int ret = 0;
2596         struct dirent **namelist = NULL;
2597         int i, items = 0;
2598         char path[PATH_MAX];
2599         pid_t pid;
2600
2601         if (symbol_conf.default_guest_vmlinux_name ||
2602             symbol_conf.default_guest_modules ||
2603             symbol_conf.default_guest_kallsyms) {
2604                 machines__create_kernel_maps(machines, DEFAULT_GUEST_KERNEL_ID);
2605         }
2606
2607         if (symbol_conf.guestmount) {
2608                 items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
2609                 if (items <= 0)
2610                         return -ENOENT;
2611                 for (i = 0; i < items; i++) {
2612                         if (!isdigit(namelist[i]->d_name[0])) {
2613                                 /* Filter out . and .. */
2614                                 continue;
2615                         }
2616                         pid = atoi(namelist[i]->d_name);
2617                         sprintf(path, "%s/%s/proc/kallsyms",
2618                                 symbol_conf.guestmount,
2619                                 namelist[i]->d_name);
2620                         ret = access(path, R_OK);
2621                         if (ret) {
2622                                 pr_debug("Can't access file %s\n", path);
2623                                 goto failure;
2624                         }
2625                         machines__create_kernel_maps(machines, pid);
2626                 }
2627 failure:
2628                 free(namelist);
2629         }
2630
2631         return ret;
2632 }
2633
2634 void machines__destroy_guest_kernel_maps(struct rb_root *machines)
2635 {
2636         struct rb_node *next = rb_first(machines);
2637
2638         while (next) {
2639                 struct machine *pos = rb_entry(next, struct machine, rb_node);
2640
2641                 next = rb_next(&pos->rb_node);
2642                 rb_erase(&pos->rb_node, machines);
2643                 machine__delete(pos);
2644         }
2645 }
2646
2647 int machine__load_kallsyms(struct machine *machine, const char *filename,
2648                            enum map_type type, symbol_filter_t filter)
2649 {
2650         struct map *map = machine->vmlinux_maps[type];
2651         int ret = dso__load_kallsyms(map->dso, filename, map, filter);
2652
2653         if (ret > 0) {
2654                 dso__set_loaded(map->dso, type);
2655                 /*
2656                  * Since /proc/kallsyms will have multiple sessions for the
2657                  * kernel, with modules between them, fixup the end of all
2658                  * sections.
2659                  */
2660                 __map_groups__fixup_end(&machine->kmaps, type);
2661         }
2662
2663         return ret;
2664 }
2665
2666 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,
2667                                symbol_filter_t filter)
2668 {
2669         struct map *map = machine->vmlinux_maps[type];
2670         int ret = dso__load_vmlinux_path(map->dso, map, filter);
2671
2672         if (ret > 0) {
2673                 dso__set_loaded(map->dso, type);
2674                 map__reloc_vmlinux(map);
2675         }
2676
2677         return ret;
2678 }