tools/perf/util/symbol.c

   1 #include <dirent.h>
   2 #include <errno.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <sys/param.h>
   9 #include <fcntl.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include "annotate.h"
  13 #include "build-id.h"
  14 #include "util.h"
  15 #include "debug.h"
  16 #include "machine.h"
  17 #include "symbol.h"
  18 #include "strlist.h"
  19 #include "intlist.h"
  20 #include "header.h"
  21
  22 #include <elf.h>
  23 #include <limits.h>
  24 #include <symbol/kallsyms.h>
  25 #include <sys/utsname.h>
  26
  27 static int dso__load_kernel_sym(struct dso *dso, struct map *map);
  28 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
  29 static bool symbol__is_idle(const char *name);
  30
  31 int vmlinux_path__nr_entries;
  32 char **vmlinux_path;
  33
  34 struct symbol_conf symbol_conf = {
  35         .use_modules            = true,
  36         .try_vmlinux_path       = true,
  37         .annotate_src           = true,
  38         .demangle               = true,
  39         .demangle_kernel        = false,
  40         .cumulate_callchain     = true,
  41         .show_hist_headers      = true,
  42         .symfs                  = "",
  43         .event_group            = true,
  44 };
  45
  46 static enum dso_binary_type binary_type_symtab[] = {
  47         DSO_BINARY_TYPE__KALLSYMS,
  48         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  49         DSO_BINARY_TYPE__JAVA_JIT,
  50         DSO_BINARY_TYPE__DEBUGLINK,
  51         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  52         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  53         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  54         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  55         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  56         DSO_BINARY_TYPE__GUEST_KMODULE,
  57         DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  58         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  59         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  60         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  61         DSO_BINARY_TYPE__NOT_FOUND,
  62 };
  63
  64 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  65
  66 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  67 {
  68         symbol_type = toupper(symbol_type);
  69
  70         switch (map_type) {
  71         case MAP__FUNCTION:
  72                 return symbol_type == 'T' || symbol_type == 'W';
  73         case MAP__VARIABLE:
  74                 return symbol_type == 'D';
  75         default:
  76                 return false;
  77         }
  78 }
  79
  80 static int prefix_underscores_count(const char *str)
  81 {
  82         const char *tail = str;
  83
  84         while (*tail == '_')
  85                 tail++;
  86
  87         return tail - str;
  88 }
  89
  90 int __weak arch__choose_best_symbol(struct symbol *syma,
  91                                     struct symbol *symb __maybe_unused)
  92 {
  93         /* Avoid "SyS" kernel syscall aliases */
  94         if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
  95                 return SYMBOL_B;
  96         if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
  97                 return SYMBOL_B;
  98
  99         return SYMBOL_A;
 100 }
 101
 102 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 103 {
 104         s64 a;
 105         s64 b;
 106         size_t na, nb;
 107
 108         /* Prefer a symbol with non zero length */
 109         a = syma->end - syma->start;
 110         b = symb->end - symb->start;
 111         if ((b == 0) && (a > 0))
 112                 return SYMBOL_A;
 113         else if ((a == 0) && (b > 0))
 114                 return SYMBOL_B;
 115
 116         /* Prefer a non weak symbol over a weak one */
 117         a = syma->binding == STB_WEAK;
 118         b = symb->binding == STB_WEAK;
 119         if (b && !a)
 120                 return SYMBOL_A;
 121         if (a && !b)
 122                 return SYMBOL_B;
 123
 124         /* Prefer a global symbol over a non global one */
 125         a = syma->binding == STB_GLOBAL;
 126         b = symb->binding == STB_GLOBAL;
 127         if (a && !b)
 128                 return SYMBOL_A;
 129         if (b && !a)
 130                 return SYMBOL_B;
 131
 132         /* Prefer a symbol with less underscores */
 133         a = prefix_underscores_count(syma->name);
 134         b = prefix_underscores_count(symb->name);
 135         if (b > a)
 136                 return SYMBOL_A;
 137         else if (a > b)
 138                 return SYMBOL_B;
 139
 140         /* Choose the symbol with the longest name */
 141         na = strlen(syma->name);
 142         nb = strlen(symb->name);
 143         if (na > nb)
 144                 return SYMBOL_A;
 145         else if (na < nb)
 146                 return SYMBOL_B;
 147
 148         return arch__choose_best_symbol(syma, symb);
 149 }
 150
 151 void symbols__fixup_duplicate(struct rb_root *symbols)
 152 {
 153         struct rb_node *nd;
 154         struct symbol *curr, *next;
 155
 156         if (symbol_conf.allow_aliases)
 157                 return;
 158
 159         nd = rb_first(symbols);
 160
 161         while (nd) {
 162                 curr = rb_entry(nd, struct symbol, rb_node);
 163 again:
 164                 nd = rb_next(&curr->rb_node);
 165                 next = rb_entry(nd, struct symbol, rb_node);
 166
 167                 if (!nd)
 168                         break;
 169
 170                 if (curr->start != next->start)
 171                         continue;
 172
 173                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 174                         rb_erase(&next->rb_node, symbols);
 175                         symbol__delete(next);
 176                         goto again;
 177                 } else {
 178                         nd = rb_next(&curr->rb_node);
 179                         rb_erase(&curr->rb_node, symbols);
 180                         symbol__delete(curr);
 181                 }
 182         }
 183 }
 184
 185 void symbols__fixup_end(struct rb_root *symbols)
 186 {
 187         struct rb_node *nd, *prevnd = rb_first(symbols);
 188         struct symbol *curr, *prev;
 189
 190         if (prevnd == NULL)
 191                 return;
 192
 193         curr = rb_entry(prevnd, struct symbol, rb_node);
 194
 195         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 196                 prev = curr;
 197                 curr = rb_entry(nd, struct symbol, rb_node);
 198
 199                 if (prev->end == prev->start && prev->end != curr->start)
 200                         prev->end = curr->start;
 201         }
 202
 203         /* Last entry */
 204         if (curr->end == curr->start)
 205                 curr->end = roundup(curr->start, 4096) + 4096;
 206 }
 207
 208 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 209 {
 210         struct maps *maps = &mg->maps[type];
 211         struct map *next, *curr;
 212
 213         pthread_rwlock_wrlock(&maps->lock);
 214
 215         curr = maps__first(maps);
 216         if (curr == NULL)
 217                 goto out_unlock;
 218
 219         for (next = map__next(curr); next; next = map__next(curr)) {
 220                 curr->end = next->start;
 221                 curr = next;
 222         }
 223
 224         /*
 225          * We still haven't the actual symbols, so guess the
 226          * last map final address.
 227          */
 228         curr->end = ~0ULL;
 229
 230 out_unlock:
 231         pthread_rwlock_unlock(&maps->lock);
 232 }
 233
 234 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 235 {
 236         size_t namelen = strlen(name) + 1;
 237         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 238                                         sizeof(*sym) + namelen));
 239         if (sym == NULL)
 240                 return NULL;
 241
 242         if (symbol_conf.priv_size) {
 243                 if (symbol_conf.init_annotation) {
 244                         struct annotation *notes = (void *)sym;
 245                         pthread_mutex_init(&notes->lock, NULL);
 246                 }
 247                 sym = ((void *)sym) + symbol_conf.priv_size;
 248         }
 249
 250         sym->start   = start;
 251         sym->end     = len ? start + len : start;
 252         sym->binding = binding;
 253         sym->namelen = namelen - 1;
 254
 255         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 256                   __func__, name, start, sym->end);
 257         memcpy(sym->name, name, namelen);
 258
 259         return sym;
 260 }
 261
 262 void symbol__delete(struct symbol *sym)
 263 {
 264         free(((void *)sym) - symbol_conf.priv_size);
 265 }
 266
 267 void symbols__delete(struct rb_root *symbols)
 268 {
 269         struct symbol *pos;
 270         struct rb_node *next = rb_first(symbols);
 271
 272         while (next) {
 273                 pos = rb_entry(next, struct symbol, rb_node);
 274                 next = rb_next(&pos->rb_node);
 275                 rb_erase(&pos->rb_node, symbols);
 276                 symbol__delete(pos);
 277         }
 278 }
 279
 280 void __symbols__insert(struct rb_root *symbols, struct symbol *sym, bool kernel)
 281 {
 282         struct rb_node **p = &symbols->rb_node;
 283         struct rb_node *parent = NULL;
 284         const u64 ip = sym->start;
 285         struct symbol *s;
 286
 287         if (kernel) {
 288                 const char *name = sym->name;
 289                 /*
 290                  * ppc64 uses function descriptors and appends a '.' to the
 291                  * start of every instruction address. Remove it.
 292                  */
 293                 if (name[0] == '.')
 294                         name++;
 295                 sym->idle = symbol__is_idle(name);
 296         }
 297
 298         while (*p != NULL) {
 299                 parent = *p;
 300                 s = rb_entry(parent, struct symbol, rb_node);
 301                 if (ip < s->start)
 302                         p = &(*p)->rb_left;
 303                 else
 304                         p = &(*p)->rb_right;
 305         }
 306         rb_link_node(&sym->rb_node, parent, p);
 307         rb_insert_color(&sym->rb_node, symbols);
 308 }
 309
 310 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 311 {
 312         __symbols__insert(symbols, sym, false);
 313 }
 314
 315 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 316 {
 317         struct rb_node *n;
 318
 319         if (symbols == NULL)
 320                 return NULL;
 321
 322         n = symbols->rb_node;
 323
 324         while (n) {
 325                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 326
 327                 if (ip < s->start)
 328                         n = n->rb_left;
 329                 else if (ip > s->end || (ip == s->end && ip != s->start))
 330                         n = n->rb_right;
 331                 else
 332                         return s;
 333         }
 334
 335         return NULL;
 336 }
 337
 338 static struct symbol *symbols__first(struct rb_root *symbols)
 339 {
 340         struct rb_node *n = rb_first(symbols);
 341
 342         if (n)
 343                 return rb_entry(n, struct symbol, rb_node);
 344
 345         return NULL;
 346 }
 347
 348 static struct symbol *symbols__last(struct rb_root *symbols)
 349 {
 350         struct rb_node *n = rb_last(symbols);
 351
 352         if (n)
 353                 return rb_entry(n, struct symbol, rb_node);
 354
 355         return NULL;
 356 }
 357
 358 static struct symbol *symbols__next(struct symbol *sym)
 359 {
 360         struct rb_node *n = rb_next(&sym->rb_node);
 361
 362         if (n)
 363                 return rb_entry(n, struct symbol, rb_node);
 364
 365         return NULL;
 366 }
 367
 368 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 369 {
 370         struct rb_node **p = &symbols->rb_node;
 371         struct rb_node *parent = NULL;
 372         struct symbol_name_rb_node *symn, *s;
 373
 374         symn = container_of(sym, struct symbol_name_rb_node, sym);
 375
 376         while (*p != NULL) {
 377                 parent = *p;
 378                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 379                 if (strcmp(sym->name, s->sym.name) < 0)
 380                         p = &(*p)->rb_left;
 381                 else
 382                         p = &(*p)->rb_right;
 383         }
 384         rb_link_node(&symn->rb_node, parent, p);
 385         rb_insert_color(&symn->rb_node, symbols);
 386 }
 387
 388 static void symbols__sort_by_name(struct rb_root *symbols,
 389                                   struct rb_root *source)
 390 {
 391         struct rb_node *nd;
 392
 393         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 394                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 395                 symbols__insert_by_name(symbols, pos);
 396         }
 397 }
 398
 399 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 400                                             const char *name)
 401 {
 402         struct rb_node *n;
 403         struct symbol_name_rb_node *s = NULL;
 404
 405         if (symbols == NULL)
 406                 return NULL;
 407
 408         n = symbols->rb_node;
 409
 410         while (n) {
 411                 int cmp;
 412
 413                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 414                 cmp = arch__compare_symbol_names(name, s->sym.name);
 415
 416                 if (cmp < 0)
 417                         n = n->rb_left;
 418                 else if (cmp > 0)
 419                         n = n->rb_right;
 420                 else
 421                         break;
 422         }
 423
 424         if (n == NULL)
 425                 return NULL;
 426
 427         /* return first symbol that has same name (if any) */
 428         for (n = rb_prev(n); n; n = rb_prev(n)) {
 429                 struct symbol_name_rb_node *tmp;
 430
 431                 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
 432                 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
 433                         break;
 434
 435                 s = tmp;
 436         }
 437
 438         return &s->sym;
 439 }
 440
 441 void dso__reset_find_symbol_cache(struct dso *dso)
 442 {
 443         enum map_type type;
 444
 445         for (type = MAP__FUNCTION; type <= MAP__VARIABLE; ++type) {
 446                 dso->last_find_result[type].addr   = 0;
 447                 dso->last_find_result[type].symbol = NULL;
 448         }
 449 }
 450
 451 void dso__insert_symbol(struct dso *dso, enum map_type type, struct symbol *sym)
 452 {
 453         __symbols__insert(&dso->symbols[type], sym, dso->kernel);
 454
 455         /* update the symbol cache if necessary */
 456         if (dso->last_find_result[type].addr >= sym->start &&
 457             (dso->last_find_result[type].addr < sym->end ||
 458             sym->start == sym->end)) {
 459                 dso->last_find_result[type].symbol = sym;
 460         }
 461 }
 462
 463 struct symbol *dso__find_symbol(struct dso *dso,
 464                                 enum map_type type, u64 addr)
 465 {
 466         if (dso->last_find_result[type].addr != addr) {
 467                 dso->last_find_result[type].addr   = addr;
 468                 dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr);
 469         }
 470
 471         return dso->last_find_result[type].symbol;
 472 }
 473
 474 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
 475 {
 476         return symbols__first(&dso->symbols[type]);
 477 }
 478
 479 struct symbol *dso__last_symbol(struct dso *dso, enum map_type type)
 480 {
 481         return symbols__last(&dso->symbols[type]);
 482 }
 483
 484 struct symbol *dso__next_symbol(struct symbol *sym)
 485 {
 486         return symbols__next(sym);
 487 }
 488
 489 struct symbol *symbol__next_by_name(struct symbol *sym)
 490 {
 491         struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
 492         struct rb_node *n = rb_next(&s->rb_node);
 493
 494         return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
 495 }
 496
 497  /*
 498   * Teturns first symbol that matched with @name.
 499   */
 500 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 501                                         const char *name)
 502 {
 503         return symbols__find_by_name(&dso->symbol_names[type], name);
 504 }
 505
 506 void dso__sort_by_name(struct dso *dso, enum map_type type)
 507 {
 508         dso__set_sorted_by_name(dso, type);
 509         return symbols__sort_by_name(&dso->symbol_names[type],
 510                                      &dso->symbols[type]);
 511 }
 512
 513 int modules__parse(const char *filename, void *arg,
 514                    int (*process_module)(void *arg, const char *name,
 515                                          u64 start))
 516 {
 517         char *line = NULL;
 518         size_t n;
 519         FILE *file;
 520         int err = 0;
 521
 522         file = fopen(filename, "r");
 523         if (file == NULL)
 524                 return -1;
 525
 526         while (1) {
 527                 char name[PATH_MAX];
 528                 u64 start;
 529                 char *sep;
 530                 ssize_t line_len;
 531
 532                 line_len = getline(&line, &n, file);
 533                 if (line_len < 0) {
 534                         if (feof(file))
 535                                 break;
 536                         err = -1;
 537                         goto out;
 538                 }
 539
 540                 if (!line) {
 541                         err = -1;
 542                         goto out;
 543                 }
 544
 545                 line[--line_len] = '\0'; /* \n */
 546
 547                 sep = strrchr(line, 'x');
 548                 if (sep == NULL)
 549                         continue;
 550
 551                 hex2u64(sep + 1, &start);
 552
 553                 sep = strchr(line, ' ');
 554                 if (sep == NULL)
 555                         continue;
 556
 557                 *sep = '\0';
 558
 559                 scnprintf(name, sizeof(name), "[%s]", line);
 560
 561                 err = process_module(arg, name, start);
 562                 if (err)
 563                         break;
 564         }
 565 out:
 566         free(line);
 567         fclose(file);
 568         return err;
 569 }
 570
 571 struct process_kallsyms_args {
 572         struct map *map;
 573         struct dso *dso;
 574 };
 575
 576 /*
 577  * These are symbols in the kernel image, so make sure that
 578  * sym is from a kernel DSO.
 579  */
 580 static bool symbol__is_idle(const char *name)
 581 {
 582         const char * const idle_symbols[] = {
 583                 "cpu_idle",
 584                 "cpu_startup_entry",
 585                 "intel_idle",
 586                 "default_idle",
 587                 "native_safe_halt",
 588                 "enter_idle",
 589                 "exit_idle",
 590                 "mwait_idle",
 591                 "mwait_idle_with_hints",
 592                 "poll_idle",
 593                 "ppc64_runlatch_off",
 594                 "pseries_dedicated_idle_sleep",
 595                 NULL
 596         };
 597         int i;
 598
 599         for (i = 0; idle_symbols[i]; i++) {
 600                 if (!strcmp(idle_symbols[i], name))
 601                         return true;
 602         }
 603
 604         return false;
 605 }
 606
 607 static int map__process_kallsym_symbol(void *arg, const char *name,
 608                                        char type, u64 start)
 609 {
 610         struct symbol *sym;
 611         struct process_kallsyms_args *a = arg;
 612         struct rb_root *root = &a->dso->symbols[a->map->type];
 613
 614         if (!symbol_type__is_a(type, a->map->type))
 615                 return 0;
 616
 617         /*
 618          * module symbols are not sorted so we add all
 619          * symbols, setting length to 0, and rely on
 620          * symbols__fixup_end() to fix it up.
 621          */
 622         sym = symbol__new(start, 0, kallsyms2elf_binding(type), name);
 623         if (sym == NULL)
 624                 return -ENOMEM;
 625         /*
 626          * We will pass the symbols to the filter later, in
 627          * map__split_kallsyms, when we have split the maps per module
 628          */
 629         __symbols__insert(root, sym, !strchr(name, '['));
 630
 631         return 0;
 632 }
 633
 634 /*
 635  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 636  * so that we can in the next step set the symbol ->end address and then
 637  * call kernel_maps__split_kallsyms.
 638  */
 639 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 640                                   struct map *map)
 641 {
 642         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 643         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 644 }
 645
 646 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map)
 647 {
 648         struct map_groups *kmaps = map__kmaps(map);
 649         struct map *curr_map;
 650         struct symbol *pos;
 651         int count = 0;
 652         struct rb_root old_root = dso->symbols[map->type];
 653         struct rb_root *root = &dso->symbols[map->type];
 654         struct rb_node *next = rb_first(root);
 655
 656         if (!kmaps)
 657                 return -1;
 658
 659         *root = RB_ROOT;
 660
 661         while (next) {
 662                 char *module;
 663
 664                 pos = rb_entry(next, struct symbol, rb_node);
 665                 next = rb_next(&pos->rb_node);
 666
 667                 rb_erase_init(&pos->rb_node, &old_root);
 668
 669                 module = strchr(pos->name, '\t');
 670                 if (module)
 671                         *module = '\0';
 672
 673                 curr_map = map_groups__find(kmaps, map->type, pos->start);
 674
 675                 if (!curr_map) {
 676                         symbol__delete(pos);
 677                         continue;
 678                 }
 679
 680                 pos->start -= curr_map->start - curr_map->pgoff;
 681                 if (pos->end)
 682                         pos->end -= curr_map->start - curr_map->pgoff;
 683                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 684                 ++count;
 685         }
 686
 687         /* Symbols have been adjusted */
 688         dso->adjust_symbols = 1;
 689
 690         return count;
 691 }
 692
 693 /*
 694  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 695  * kernel range is broken in several maps, named [kernel].N, as we don't have
 696  * the original ELF section names vmlinux have.
 697  */
 698 static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta)
 699 {
 700         struct map_groups *kmaps = map__kmaps(map);
 701         struct machine *machine;
 702         struct map *curr_map = map;
 703         struct symbol *pos;
 704         int count = 0, moved = 0;
 705         struct rb_root *root = &dso->symbols[map->type];
 706         struct rb_node *next = rb_first(root);
 707         int kernel_range = 0;
 708
 709         if (!kmaps)
 710                 return -1;
 711
 712         machine = kmaps->machine;
 713
 714         while (next) {
 715                 char *module;
 716
 717                 pos = rb_entry(next, struct symbol, rb_node);
 718                 next = rb_next(&pos->rb_node);
 719
 720                 module = strchr(pos->name, '\t');
 721                 if (module) {
 722                         if (!symbol_conf.use_modules)
 723                                 goto discard_symbol;
 724
 725                         *module++ = '\0';
 726
 727                         if (strcmp(curr_map->dso->short_name, module)) {
 728                                 if (curr_map != map &&
 729                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 730                                     machine__is_default_guest(machine)) {
 731                                         /*
 732                                          * We assume all symbols of a module are
 733                                          * continuous in * kallsyms, so curr_map
 734                                          * points to a module and all its
 735                                          * symbols are in its kmap. Mark it as
 736                                          * loaded.
 737                                          */
 738                                         dso__set_loaded(curr_map->dso,
 739                                                         curr_map->type);
 740                                 }
 741
 742                                 curr_map = map_groups__find_by_name(kmaps,
 743                                                         map->type, module);
 744                                 if (curr_map == NULL) {
 745                                         pr_debug("%s/proc/{kallsyms,modules} "
 746                                                  "inconsistency while looking "
 747                                                  "for \"%s\" module!\n",
 748                                                  machine->root_dir, module);
 749                                         curr_map = map;
 750                                         goto discard_symbol;
 751                                 }
 752
 753                                 if (curr_map->dso->loaded &&
 754                                     !machine__is_default_guest(machine))
 755                                         goto discard_symbol;
 756                         }
 757                         /*
 758                          * So that we look just like we get from .ko files,
 759                          * i.e. not prelinked, relative to map->start.
 760                          */
 761                         pos->start = curr_map->map_ip(curr_map, pos->start);
 762                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 763                 } else if (curr_map != map) {
 764                         char dso_name[PATH_MAX];
 765                         struct dso *ndso;
 766
 767                         if (delta) {
 768                                 /* Kernel was relocated at boot time */
 769                                 pos->start -= delta;
 770                                 pos->end -= delta;
 771                         }
 772
 773                         if (count == 0) {
 774                                 curr_map = map;
 775                                 goto add_symbol;
 776                         }
 777
 778                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 779                                 snprintf(dso_name, sizeof(dso_name),
 780                                         "[guest.kernel].%d",
 781                                         kernel_range++);
 782                         else
 783                                 snprintf(dso_name, sizeof(dso_name),
 784                                         "[kernel].%d",
 785                                         kernel_range++);
 786
 787                         ndso = dso__new(dso_name);
 788                         if (ndso == NULL)
 789                                 return -1;
 790
 791                         ndso->kernel = dso->kernel;
 792
 793                         curr_map = map__new2(pos->start, ndso, map->type);
 794                         if (curr_map == NULL) {
 795                                 dso__put(ndso);
 796                                 return -1;
 797                         }
 798
 799                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 800                         map_groups__insert(kmaps, curr_map);
 801                         ++kernel_range;
 802                 } else if (delta) {
 803                         /* Kernel was relocated at boot time */
 804                         pos->start -= delta;
 805                         pos->end -= delta;
 806                 }
 807 add_symbol:
 808                 if (curr_map != map) {
 809                         rb_erase(&pos->rb_node, root);
 810                         symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 811                         ++moved;
 812                 } else
 813                         ++count;
 814
 815                 continue;
 816 discard_symbol:
 817                 rb_erase(&pos->rb_node, root);
 818                 symbol__delete(pos);
 819         }
 820
 821         if (curr_map != map &&
 822             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 823             machine__is_default_guest(kmaps->machine)) {
 824                 dso__set_loaded(curr_map->dso, curr_map->type);
 825         }
 826
 827         return count + moved;
 828 }
 829
 830 bool symbol__restricted_filename(const char *filename,
 831                                  const char *restricted_filename)
 832 {
 833         bool restricted = false;
 834
 835         if (symbol_conf.kptr_restrict) {
 836                 char *r = realpath(filename, NULL);
 837
 838                 if (r != NULL) {
 839                         restricted = strcmp(r, restricted_filename) == 0;
 840                         free(r);
 841                         return restricted;
 842                 }
 843         }
 844
 845         return restricted;
 846 }
 847
 848 struct module_info {
 849         struct rb_node rb_node;
 850         char *name;
 851         u64 start;
 852 };
 853
 854 static void add_module(struct module_info *mi, struct rb_root *modules)
 855 {
 856         struct rb_node **p = &modules->rb_node;
 857         struct rb_node *parent = NULL;
 858         struct module_info *m;
 859
 860         while (*p != NULL) {
 861                 parent = *p;
 862                 m = rb_entry(parent, struct module_info, rb_node);
 863                 if (strcmp(mi->name, m->name) < 0)
 864                         p = &(*p)->rb_left;
 865                 else
 866                         p = &(*p)->rb_right;
 867         }
 868         rb_link_node(&mi->rb_node, parent, p);
 869         rb_insert_color(&mi->rb_node, modules);
 870 }
 871
 872 static void delete_modules(struct rb_root *modules)
 873 {
 874         struct module_info *mi;
 875         struct rb_node *next = rb_first(modules);
 876
 877         while (next) {
 878                 mi = rb_entry(next, struct module_info, rb_node);
 879                 next = rb_next(&mi->rb_node);
 880                 rb_erase(&mi->rb_node, modules);
 881                 zfree(&mi->name);
 882                 free(mi);
 883         }
 884 }
 885
 886 static struct module_info *find_module(const char *name,
 887                                        struct rb_root *modules)
 888 {
 889         struct rb_node *n = modules->rb_node;
 890
 891         while (n) {
 892                 struct module_info *m;
 893                 int cmp;
 894
 895                 m = rb_entry(n, struct module_info, rb_node);
 896                 cmp = strcmp(name, m->name);
 897                 if (cmp < 0)
 898                         n = n->rb_left;
 899                 else if (cmp > 0)
 900                         n = n->rb_right;
 901                 else
 902                         return m;
 903         }
 904
 905         return NULL;
 906 }
 907
 908 static int __read_proc_modules(void *arg, const char *name, u64 start)
 909 {
 910         struct rb_root *modules = arg;
 911         struct module_info *mi;
 912
 913         mi = zalloc(sizeof(struct module_info));
 914         if (!mi)
 915                 return -ENOMEM;
 916
 917         mi->name = strdup(name);
 918         mi->start = start;
 919
 920         if (!mi->name) {
 921                 free(mi);
 922                 return -ENOMEM;
 923         }
 924
 925         add_module(mi, modules);
 926
 927         return 0;
 928 }
 929
 930 static int read_proc_modules(const char *filename, struct rb_root *modules)
 931 {
 932         if (symbol__restricted_filename(filename, "/proc/modules"))
 933                 return -1;
 934
 935         if (modules__parse(filename, modules, __read_proc_modules)) {
 936                 delete_modules(modules);
 937                 return -1;
 938         }
 939
 940         return 0;
 941 }
 942
 943 int compare_proc_modules(const char *from, const char *to)
 944 {
 945         struct rb_root from_modules = RB_ROOT;
 946         struct rb_root to_modules = RB_ROOT;
 947         struct rb_node *from_node, *to_node;
 948         struct module_info *from_m, *to_m;
 949         int ret = -1;
 950
 951         if (read_proc_modules(from, &from_modules))
 952                 return -1;
 953
 954         if (read_proc_modules(to, &to_modules))
 955                 goto out_delete_from;
 956
 957         from_node = rb_first(&from_modules);
 958         to_node = rb_first(&to_modules);
 959         while (from_node) {
 960                 if (!to_node)
 961                         break;
 962
 963                 from_m = rb_entry(from_node, struct module_info, rb_node);
 964                 to_m = rb_entry(to_node, struct module_info, rb_node);
 965
 966                 if (from_m->start != to_m->start ||
 967                     strcmp(from_m->name, to_m->name))
 968                         break;
 969
 970                 from_node = rb_next(from_node);
 971                 to_node = rb_next(to_node);
 972         }
 973
 974         if (!from_node && !to_node)
 975                 ret = 0;
 976
 977         delete_modules(&to_modules);
 978 out_delete_from:
 979         delete_modules(&from_modules);
 980
 981         return ret;
 982 }
 983
 984 static int do_validate_kcore_modules(const char *filename, struct map *map,
 985                                   struct map_groups *kmaps)
 986 {
 987         struct rb_root modules = RB_ROOT;
 988         struct map *old_map;
 989         int err;
 990
 991         err = read_proc_modules(filename, &modules);
 992         if (err)
 993                 return err;
 994
 995         old_map = map_groups__first(kmaps, map->type);
 996         while (old_map) {
 997                 struct map *next = map_groups__next(old_map);
 998                 struct module_info *mi;
 999
1000                 if (old_map == map || old_map->start == map->start) {
1001                         /* The kernel map */
1002                         old_map = next;
1003                         continue;
1004                 }
1005
1006                 /* Module must be in memory at the same address */
1007                 mi = find_module(old_map->dso->short_name, &modules);
1008                 if (!mi || mi->start != old_map->start) {
1009                         err = -EINVAL;
1010                         goto out;
1011                 }
1012
1013                 old_map = next;
1014         }
1015 out:
1016         delete_modules(&modules);
1017         return err;
1018 }
1019
1020 /*
1021  * If kallsyms is referenced by name then we look for filename in the same
1022  * directory.
1023  */
1024 static bool filename_from_kallsyms_filename(char *filename,
1025                                             const char *base_name,
1026                                             const char *kallsyms_filename)
1027 {
1028         char *name;
1029
1030         strcpy(filename, kallsyms_filename);
1031         name = strrchr(filename, '/');
1032         if (!name)
1033                 return false;
1034
1035         name += 1;
1036
1037         if (!strcmp(name, "kallsyms")) {
1038                 strcpy(name, base_name);
1039                 return true;
1040         }
1041
1042         return false;
1043 }
1044
1045 static int validate_kcore_modules(const char *kallsyms_filename,
1046                                   struct map *map)
1047 {
1048         struct map_groups *kmaps = map__kmaps(map);
1049         char modules_filename[PATH_MAX];
1050
1051         if (!kmaps)
1052                 return -EINVAL;
1053
1054         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1055                                              kallsyms_filename))
1056                 return -EINVAL;
1057
1058         if (do_validate_kcore_modules(modules_filename, map, kmaps))
1059                 return -EINVAL;
1060
1061         return 0;
1062 }
1063
1064 static int validate_kcore_addresses(const char *kallsyms_filename,
1065                                     struct map *map)
1066 {
1067         struct kmap *kmap = map__kmap(map);
1068
1069         if (!kmap)
1070                 return -EINVAL;
1071
1072         if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1073                 u64 start;
1074
1075                 start = kallsyms__get_function_start(kallsyms_filename,
1076                                                      kmap->ref_reloc_sym->name);
1077                 if (start != kmap->ref_reloc_sym->addr)
1078                         return -EINVAL;
1079         }
1080
1081         return validate_kcore_modules(kallsyms_filename, map);
1082 }
1083
1084 struct kcore_mapfn_data {
1085         struct dso *dso;
1086         enum map_type type;
1087         struct list_head maps;
1088 };
1089
1090 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1091 {
1092         struct kcore_mapfn_data *md = data;
1093         struct map *map;
1094
1095         map = map__new2(start, md->dso, md->type);
1096         if (map == NULL)
1097                 return -ENOMEM;
1098
1099         map->end = map->start + len;
1100         map->pgoff = pgoff;
1101
1102         list_add(&map->node, &md->maps);
1103
1104         return 0;
1105 }
1106
1107 static int dso__load_kcore(struct dso *dso, struct map *map,
1108                            const char *kallsyms_filename)
1109 {
1110         struct map_groups *kmaps = map__kmaps(map);
1111         struct machine *machine;
1112         struct kcore_mapfn_data md;
1113         struct map *old_map, *new_map, *replacement_map = NULL;
1114         bool is_64_bit;
1115         int err, fd;
1116         char kcore_filename[PATH_MAX];
1117         struct symbol *sym;
1118
1119         if (!kmaps)
1120                 return -EINVAL;
1121
1122         machine = kmaps->machine;
1123
1124         /* This function requires that the map is the kernel map */
1125         if (map != machine->vmlinux_maps[map->type])
1126                 return -EINVAL;
1127
1128         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1129                                              kallsyms_filename))
1130                 return -EINVAL;
1131
1132         /* Modules and kernel must be present at their original addresses */
1133         if (validate_kcore_addresses(kallsyms_filename, map))
1134                 return -EINVAL;
1135
1136         md.dso = dso;
1137         md.type = map->type;
1138         INIT_LIST_HEAD(&md.maps);
1139
1140         fd = open(kcore_filename, O_RDONLY);
1141         if (fd < 0) {
1142                 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1143                          kcore_filename);
1144                 return -EINVAL;
1145         }
1146
1147         /* Read new maps into temporary lists */
1148         err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1149                               &is_64_bit);
1150         if (err)
1151                 goto out_err;
1152         dso->is_64_bit = is_64_bit;
1153
1154         if (list_empty(&md.maps)) {
1155                 err = -EINVAL;
1156                 goto out_err;
1157         }
1158
1159         /* Remove old maps */
1160         old_map = map_groups__first(kmaps, map->type);
1161         while (old_map) {
1162                 struct map *next = map_groups__next(old_map);
1163
1164                 if (old_map != map)
1165                         map_groups__remove(kmaps, old_map);
1166                 old_map = next;
1167         }
1168
1169         /* Find the kernel map using the first symbol */
1170         sym = dso__first_symbol(dso, map->type);
1171         list_for_each_entry(new_map, &md.maps, node) {
1172                 if (sym && sym->start >= new_map->start &&
1173                     sym->start < new_map->end) {
1174                         replacement_map = new_map;
1175                         break;
1176                 }
1177         }
1178
1179         if (!replacement_map)
1180                 replacement_map = list_entry(md.maps.next, struct map, node);
1181
1182         /* Add new maps */
1183         while (!list_empty(&md.maps)) {
1184                 new_map = list_entry(md.maps.next, struct map, node);
1185                 list_del_init(&new_map->node);
1186                 if (new_map == replacement_map) {
1187                         map->start      = new_map->start;
1188                         map->end        = new_map->end;
1189                         map->pgoff      = new_map->pgoff;
1190                         map->map_ip     = new_map->map_ip;
1191                         map->unmap_ip   = new_map->unmap_ip;
1192                         /* Ensure maps are correctly ordered */
1193                         map__get(map);
1194                         map_groups__remove(kmaps, map);
1195                         map_groups__insert(kmaps, map);
1196                         map__put(map);
1197                 } else {
1198                         map_groups__insert(kmaps, new_map);
1199                 }
1200
1201                 map__put(new_map);
1202         }
1203
1204         /*
1205          * Set the data type and long name so that kcore can be read via
1206          * dso__data_read_addr().
1207          */
1208         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1209                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1210         else
1211                 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1212         dso__set_long_name(dso, strdup(kcore_filename), true);
1213
1214         close(fd);
1215
1216         if (map->type == MAP__FUNCTION)
1217                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1218         else
1219                 pr_debug("Using %s for kernel data\n", kcore_filename);
1220
1221         return 0;
1222
1223 out_err:
1224         while (!list_empty(&md.maps)) {
1225                 map = list_entry(md.maps.next, struct map, node);
1226                 list_del_init(&map->node);
1227                 map__put(map);
1228         }
1229         close(fd);
1230         return -EINVAL;
1231 }
1232
1233 /*
1234  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1235  * delta based on the relocation reference symbol.
1236  */
1237 static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
1238 {
1239         struct kmap *kmap = map__kmap(map);
1240         u64 addr;
1241
1242         if (!kmap)
1243                 return -1;
1244
1245         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1246                 return 0;
1247
1248         addr = kallsyms__get_function_start(filename,
1249                                             kmap->ref_reloc_sym->name);
1250         if (!addr)
1251                 return -1;
1252
1253         *delta = addr - kmap->ref_reloc_sym->addr;
1254         return 0;
1255 }
1256
1257 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1258                          struct map *map, bool no_kcore)
1259 {
1260         u64 delta = 0;
1261
1262         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1263                 return -1;
1264
1265         if (dso__load_all_kallsyms(dso, filename, map) < 0)
1266                 return -1;
1267
1268         if (kallsyms__delta(map, filename, &delta))
1269                 return -1;
1270
1271         symbols__fixup_end(&dso->symbols[map->type]);
1272         symbols__fixup_duplicate(&dso->symbols[map->type]);
1273
1274         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1275                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1276         else
1277                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1278
1279         if (!no_kcore && !dso__load_kcore(dso, map, filename))
1280                 return dso__split_kallsyms_for_kcore(dso, map);
1281         else
1282                 return dso__split_kallsyms(dso, map, delta);
1283 }
1284
1285 int dso__load_kallsyms(struct dso *dso, const char *filename,
1286                        struct map *map)
1287 {
1288         return __dso__load_kallsyms(dso, filename, map, false);
1289 }
1290
1291 static int dso__load_perf_map(struct dso *dso, struct map *map)
1292 {
1293         char *line = NULL;
1294         size_t n;
1295         FILE *file;
1296         int nr_syms = 0;
1297
1298         file = fopen(dso->long_name, "r");
1299         if (file == NULL)
1300                 goto out_failure;
1301
1302         while (!feof(file)) {
1303                 u64 start, size;
1304                 struct symbol *sym;
1305                 int line_len, len;
1306
1307                 line_len = getline(&line, &n, file);
1308                 if (line_len < 0)
1309                         break;
1310
1311                 if (!line)
1312                         goto out_failure;
1313
1314                 line[--line_len] = '\0'; /* \n */
1315
1316                 len = hex2u64(line, &start);
1317
1318                 len++;
1319                 if (len + 2 >= line_len)
1320                         continue;
1321
1322                 len += hex2u64(line + len, &size);
1323
1324                 len++;
1325                 if (len + 2 >= line_len)
1326                         continue;
1327
1328                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
1329
1330                 if (sym == NULL)
1331                         goto out_delete_line;
1332
1333                 symbols__insert(&dso->symbols[map->type], sym);
1334                 nr_syms++;
1335         }
1336
1337         free(line);
1338         fclose(file);
1339
1340         return nr_syms;
1341
1342 out_delete_line:
1343         free(line);
1344 out_failure:
1345         return -1;
1346 }
1347
1348 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1349                                            enum dso_binary_type type)
1350 {
1351         switch (type) {
1352         case DSO_BINARY_TYPE__JAVA_JIT:
1353         case DSO_BINARY_TYPE__DEBUGLINK:
1354         case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1355         case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1356         case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1357         case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1358         case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1359                 return !kmod && dso->kernel == DSO_TYPE_USER;
1360
1361         case DSO_BINARY_TYPE__KALLSYMS:
1362         case DSO_BINARY_TYPE__VMLINUX:
1363         case DSO_BINARY_TYPE__KCORE:
1364                 return dso->kernel == DSO_TYPE_KERNEL;
1365
1366         case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1367         case DSO_BINARY_TYPE__GUEST_VMLINUX:
1368         case DSO_BINARY_TYPE__GUEST_KCORE:
1369                 return dso->kernel == DSO_TYPE_GUEST_KERNEL;
1370
1371         case DSO_BINARY_TYPE__GUEST_KMODULE:
1372         case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1373         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1374         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1375                 /*
1376                  * kernel modules know their symtab type - it's set when
1377                  * creating a module dso in machine__findnew_module_map().
1378                  */
1379                 return kmod && dso->symtab_type == type;
1380
1381         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1382                 return true;
1383
1384         case DSO_BINARY_TYPE__NOT_FOUND:
1385         default:
1386                 return false;
1387         }
1388 }
1389
1390 int dso__load(struct dso *dso, struct map *map)
1391 {
1392         char *name;
1393         int ret = -1;
1394         u_int i;
1395         struct machine *machine;
1396         char *root_dir = (char *) "";
1397         int ss_pos = 0;
1398         struct symsrc ss_[2];
1399         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1400         bool kmod;
1401         unsigned char build_id[BUILD_ID_SIZE];
1402
1403         pthread_mutex_lock(&dso->lock);
1404
1405         /* check again under the dso->lock */
1406         if (dso__loaded(dso, map->type)) {
1407                 ret = 1;
1408                 goto out;
1409         }
1410
1411         if (dso->kernel) {
1412                 if (dso->kernel == DSO_TYPE_KERNEL)
1413                         ret = dso__load_kernel_sym(dso, map);
1414                 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1415                         ret = dso__load_guest_kernel_sym(dso, map);
1416
1417                 goto out;
1418         }
1419
1420         if (map->groups && map->groups->machine)
1421                 machine = map->groups->machine;
1422         else
1423                 machine = NULL;
1424
1425         dso->adjust_symbols = 0;
1426
1427         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1428                 struct stat st;
1429
1430                 if (lstat(dso->name, &st) < 0)
1431                         goto out;
1432
1433                 if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
1434                         pr_warning("File %s not owned by current user or root, "
1435                                    "ignoring it (use -f to override).\n", dso->name);
1436                         goto out;
1437                 }
1438
1439                 ret = dso__load_perf_map(dso, map);
1440                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1441                                              DSO_BINARY_TYPE__NOT_FOUND;
1442                 goto out;
1443         }
1444
1445         if (machine)
1446                 root_dir = machine->root_dir;
1447
1448         name = malloc(PATH_MAX);
1449         if (!name)
1450                 goto out;
1451
1452         kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1453                 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1454                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1455                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1456
1457
1458         /*
1459          * Read the build id if possible. This is required for
1460          * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1461          */
1462         if (!dso->has_build_id &&
1463             is_regular_file(dso->long_name) &&
1464             filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0)
1465                 dso__set_build_id(dso, build_id);
1466
1467         /*
1468          * Iterate over candidate debug images.
1469          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1470          * and/or opd section) for processing.
1471          */
1472         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1473                 struct symsrc *ss = &ss_[ss_pos];
1474                 bool next_slot = false;
1475
1476                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1477
1478                 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1479                         continue;
1480
1481                 if (dso__read_binary_type_filename(dso, symtab_type,
1482                                                    root_dir, name, PATH_MAX))
1483                         continue;
1484
1485                 if (!is_regular_file(name))
1486                         continue;
1487
1488                 /* Name is now the name of the next image to try */
1489                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
1490                         continue;
1491
1492                 if (!syms_ss && symsrc__has_symtab(ss)) {
1493                         syms_ss = ss;
1494                         next_slot = true;
1495                         if (!dso->symsrc_filename)
1496                                 dso->symsrc_filename = strdup(name);
1497                 }
1498
1499                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1500                         runtime_ss = ss;
1501                         next_slot = true;
1502                 }
1503
1504                 if (next_slot) {
1505                         ss_pos++;
1506
1507                         if (syms_ss && runtime_ss)
1508                                 break;
1509                 } else {
1510                         symsrc__destroy(ss);
1511                 }
1512
1513         }
1514
1515         if (!runtime_ss && !syms_ss)
1516                 goto out_free;
1517
1518         if (runtime_ss && !syms_ss) {
1519                 syms_ss = runtime_ss;
1520         }
1521
1522         /* We'll have to hope for the best */
1523         if (!runtime_ss && syms_ss)
1524                 runtime_ss = syms_ss;
1525
1526         if (syms_ss && syms_ss->type == DSO_BINARY_TYPE__BUILD_ID_CACHE)
1527                 if (dso__build_id_is_kmod(dso, name, PATH_MAX))
1528                         kmod = true;
1529
1530         if (syms_ss)
1531                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1532         else
1533                 ret = -1;
1534
1535         if (ret > 0) {
1536                 int nr_plt;
1537
1538                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map);
1539                 if (nr_plt > 0)
1540                         ret += nr_plt;
1541         }
1542
1543         for (; ss_pos > 0; ss_pos--)
1544                 symsrc__destroy(&ss_[ss_pos - 1]);
1545 out_free:
1546         free(name);
1547         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1548                 ret = 0;
1549 out:
1550         dso__set_loaded(dso, map->type);
1551         pthread_mutex_unlock(&dso->lock);
1552
1553         return ret;
1554 }
1555
1556 struct map *map_groups__find_by_name(struct map_groups *mg,
1557                                      enum map_type type, const char *name)
1558 {
1559         struct maps *maps = &mg->maps[type];
1560         struct map *map;
1561
1562         pthread_rwlock_rdlock(&maps->lock);
1563
1564         for (map = maps__first(maps); map; map = map__next(map)) {
1565                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1566                         goto out_unlock;
1567         }
1568
1569         map = NULL;
1570
1571 out_unlock:
1572         pthread_rwlock_unlock(&maps->lock);
1573         return map;
1574 }
1575
1576 int dso__load_vmlinux(struct dso *dso, struct map *map,
1577                       const char *vmlinux, bool vmlinux_allocated)
1578 {
1579         int err = -1;
1580         struct symsrc ss;
1581         char symfs_vmlinux[PATH_MAX];
1582         enum dso_binary_type symtab_type;
1583
1584         if (vmlinux[0] == '/')
1585                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1586         else
1587                 symbol__join_symfs(symfs_vmlinux, vmlinux);
1588
1589         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1590                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1591         else
1592                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1593
1594         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1595                 return -1;
1596
1597         err = dso__load_sym(dso, map, &ss, &ss, 0);
1598         symsrc__destroy(&ss);
1599
1600         if (err > 0) {
1601                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1602                         dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1603                 else
1604                         dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1605                 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1606                 dso__set_loaded(dso, map->type);
1607                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1608         }
1609
1610         return err;
1611 }
1612
1613 int dso__load_vmlinux_path(struct dso *dso, struct map *map)
1614 {
1615         int i, err = 0;
1616         char *filename = NULL;
1617
1618         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1619                  vmlinux_path__nr_entries + 1);
1620
1621         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1622                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
1623                 if (err > 0)
1624                         goto out;
1625         }
1626
1627         if (!symbol_conf.ignore_vmlinux_buildid)
1628                 filename = dso__build_id_filename(dso, NULL, 0);
1629         if (filename != NULL) {
1630                 err = dso__load_vmlinux(dso, map, filename, true);
1631                 if (err > 0)
1632                         goto out;
1633                 free(filename);
1634         }
1635 out:
1636         return err;
1637 }
1638
1639 static bool visible_dir_filter(const char *name, struct dirent *d)
1640 {
1641         if (d->d_type != DT_DIR)
1642                 return false;
1643         return lsdir_no_dot_filter(name, d);
1644 }
1645
1646 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1647 {
1648         char kallsyms_filename[PATH_MAX];
1649         int ret = -1;
1650         struct strlist *dirs;
1651         struct str_node *nd;
1652
1653         dirs = lsdir(dir, visible_dir_filter);
1654         if (!dirs)
1655                 return -1;
1656
1657         strlist__for_each_entry(nd, dirs) {
1658                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1659                           "%s/%s/kallsyms", dir, nd->s);
1660                 if (!validate_kcore_addresses(kallsyms_filename, map)) {
1661                         strlcpy(dir, kallsyms_filename, dir_sz);
1662                         ret = 0;
1663                         break;
1664                 }
1665         }
1666
1667         strlist__delete(dirs);
1668
1669         return ret;
1670 }
1671
1672 /*
1673  * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
1674  * since access(R_OK) only checks with real UID/GID but open() use effective
1675  * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
1676  */
1677 static bool filename__readable(const char *file)
1678 {
1679         int fd = open(file, O_RDONLY);
1680         if (fd < 0)
1681                 return false;
1682         close(fd);
1683         return true;
1684 }
1685
1686 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1687 {
1688         u8 host_build_id[BUILD_ID_SIZE];
1689         char sbuild_id[SBUILD_ID_SIZE];
1690         bool is_host = false;
1691         char path[PATH_MAX];
1692
1693         if (!dso->has_build_id) {
1694                 /*
1695                  * Last resort, if we don't have a build-id and couldn't find
1696                  * any vmlinux file, try the running kernel kallsyms table.
1697                  */
1698                 goto proc_kallsyms;
1699         }
1700
1701         if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1702                                  sizeof(host_build_id)) == 0)
1703                 is_host = dso__build_id_equal(dso, host_build_id);
1704
1705         /* Try a fast path for /proc/kallsyms if possible */
1706         if (is_host) {
1707                 /*
1708                  * Do not check the build-id cache, unless we know we cannot use
1709                  * /proc/kcore or module maps don't match to /proc/kallsyms.
1710                  * To check readability of /proc/kcore, do not use access(R_OK)
1711                  * since /proc/kcore requires CAP_SYS_RAWIO to read and access
1712                  * can't check it.
1713                  */
1714                 if (filename__readable("/proc/kcore") &&
1715                     !validate_kcore_addresses("/proc/kallsyms", map))
1716                         goto proc_kallsyms;
1717         }
1718
1719         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1720
1721         /* Find kallsyms in build-id cache with kcore */
1722         scnprintf(path, sizeof(path), "%s/%s/%s",
1723                   buildid_dir, DSO__NAME_KCORE, sbuild_id);
1724
1725         if (!find_matching_kcore(map, path, sizeof(path)))
1726                 return strdup(path);
1727
1728         /* Use current /proc/kallsyms if possible */
1729         if (is_host) {
1730 proc_kallsyms:
1731                 return strdup("/proc/kallsyms");
1732         }
1733
1734         /* Finally, find a cache of kallsyms */
1735         if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
1736                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1737                        sbuild_id);
1738                 return NULL;
1739         }
1740
1741         return strdup(path);
1742 }
1743
1744 static int dso__load_kernel_sym(struct dso *dso, struct map *map)
1745 {
1746         int err;
1747         const char *kallsyms_filename = NULL;
1748         char *kallsyms_allocated_filename = NULL;
1749         /*
1750          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1751          * it and only it, reporting errors to the user if it cannot be used.
1752          *
1753          * For instance, try to analyse an ARM perf.data file _without_ a
1754          * build-id, or if the user specifies the wrong path to the right
1755          * vmlinux file, obviously we can't fallback to another vmlinux (a
1756          * x86_86 one, on the machine where analysis is being performed, say),
1757          * or worse, /proc/kallsyms.
1758          *
1759          * If the specified file _has_ a build-id and there is a build-id
1760          * section in the perf.data file, we will still do the expected
1761          * validation in dso__load_vmlinux and will bail out if they don't
1762          * match.
1763          */
1764         if (symbol_conf.kallsyms_name != NULL) {
1765                 kallsyms_filename = symbol_conf.kallsyms_name;
1766                 goto do_kallsyms;
1767         }
1768
1769         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1770                 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
1771         }
1772
1773         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1774                 err = dso__load_vmlinux_path(dso, map);
1775                 if (err > 0)
1776                         return err;
1777         }
1778
1779         /* do not try local files if a symfs was given */
1780         if (symbol_conf.symfs[0] != 0)
1781                 return -1;
1782
1783         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1784         if (!kallsyms_allocated_filename)
1785                 return -1;
1786
1787         kallsyms_filename = kallsyms_allocated_filename;
1788
1789 do_kallsyms:
1790         err = dso__load_kallsyms(dso, kallsyms_filename, map);
1791         if (err > 0)
1792                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1793         free(kallsyms_allocated_filename);
1794
1795         if (err > 0 && !dso__is_kcore(dso)) {
1796                 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
1797                 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
1798                 map__fixup_start(map);
1799                 map__fixup_end(map);
1800         }
1801
1802         return err;
1803 }
1804
1805 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
1806 {
1807         int err;
1808         const char *kallsyms_filename = NULL;
1809         struct machine *machine;
1810         char path[PATH_MAX];
1811
1812         if (!map->groups) {
1813                 pr_debug("Guest kernel map hasn't the point to groups\n");
1814                 return -1;
1815         }
1816         machine = map->groups->machine;
1817
1818         if (machine__is_default_guest(machine)) {
1819                 /*
1820                  * if the user specified a vmlinux filename, use it and only
1821                  * it, reporting errors to the user if it cannot be used.
1822                  * Or use file guest_kallsyms inputted by user on commandline
1823                  */
1824                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1825                         err = dso__load_vmlinux(dso, map,
1826                                                 symbol_conf.default_guest_vmlinux_name,
1827                                                 false);
1828                         return err;
1829                 }
1830
1831                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1832                 if (!kallsyms_filename)
1833                         return -1;
1834         } else {
1835                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1836                 kallsyms_filename = path;
1837         }
1838
1839         err = dso__load_kallsyms(dso, kallsyms_filename, map);
1840         if (err > 0)
1841                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1842         if (err > 0 && !dso__is_kcore(dso)) {
1843                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1844                 machine__mmap_name(machine, path, sizeof(path));
1845                 dso__set_long_name(dso, strdup(path), true);
1846                 map__fixup_start(map);
1847                 map__fixup_end(map);
1848         }
1849
1850         return err;
1851 }
1852
1853 static void vmlinux_path__exit(void)
1854 {
1855         while (--vmlinux_path__nr_entries >= 0)
1856                 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1857         vmlinux_path__nr_entries = 0;
1858
1859         zfree(&vmlinux_path);
1860 }
1861
1862 static const char * const vmlinux_paths[] = {
1863         "vmlinux",
1864         "/boot/vmlinux"
1865 };
1866
1867 static const char * const vmlinux_paths_upd[] = {
1868         "/boot/vmlinux-%s",
1869         "/usr/lib/debug/boot/vmlinux-%s",
1870         "/lib/modules/%s/build/vmlinux",
1871         "/usr/lib/debug/lib/modules/%s/vmlinux",
1872         "/usr/lib/debug/boot/vmlinux-%s.debug"
1873 };
1874
1875 static int vmlinux_path__add(const char *new_entry)
1876 {
1877         vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
1878         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1879                 return -1;
1880         ++vmlinux_path__nr_entries;
1881
1882         return 0;
1883 }
1884
1885 static int vmlinux_path__init(struct perf_env *env)
1886 {
1887         struct utsname uts;
1888         char bf[PATH_MAX];
1889         char *kernel_version;
1890         unsigned int i;
1891
1892         vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
1893                               ARRAY_SIZE(vmlinux_paths_upd)));
1894         if (vmlinux_path == NULL)
1895                 return -1;
1896
1897         for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
1898                 if (vmlinux_path__add(vmlinux_paths[i]) < 0)
1899                         goto out_fail;
1900
1901         /* only try kernel version if no symfs was given */
1902         if (symbol_conf.symfs[0] != 0)
1903                 return 0;
1904
1905         if (env) {
1906                 kernel_version = env->os_release;
1907         } else {
1908                 if (uname(&uts) < 0)
1909                         goto out_fail;
1910
1911                 kernel_version = uts.release;
1912         }
1913
1914         for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
1915                 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
1916                 if (vmlinux_path__add(bf) < 0)
1917                         goto out_fail;
1918         }
1919
1920         return 0;
1921
1922 out_fail:
1923         vmlinux_path__exit();
1924         return -1;
1925 }
1926
1927 int setup_list(struct strlist **list, const char *list_str,
1928                       const char *list_name)
1929 {
1930         if (list_str == NULL)
1931                 return 0;
1932
1933         *list = strlist__new(list_str, NULL);
1934         if (!*list) {
1935                 pr_err("problems parsing %s list\n", list_name);
1936                 return -1;
1937         }
1938
1939         symbol_conf.has_filter = true;
1940         return 0;
1941 }
1942
1943 int setup_intlist(struct intlist **list, const char *list_str,
1944                   const char *list_name)
1945 {
1946         if (list_str == NULL)
1947                 return 0;
1948
1949         *list = intlist__new(list_str);
1950         if (!*list) {
1951                 pr_err("problems parsing %s list\n", list_name);
1952                 return -1;
1953         }
1954         return 0;
1955 }
1956
1957 static bool symbol__read_kptr_restrict(void)
1958 {
1959         bool value = false;
1960         FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1961
1962         if (fp != NULL) {
1963                 char line[8];
1964
1965                 if (fgets(line, sizeof(line), fp) != NULL)
1966                         value = (geteuid() != 0) ?
1967                                         (atoi(line) != 0) :
1968                                         (atoi(line) == 2);
1969
1970                 fclose(fp);
1971         }
1972
1973         return value;
1974 }
1975
1976 int symbol__annotation_init(void)
1977 {
1978         if (symbol_conf.initialized) {
1979                 pr_err("Annotation needs to be init before symbol__init()\n");
1980                 return -1;
1981         }
1982
1983         if (symbol_conf.init_annotation) {
1984                 pr_warning("Annotation being initialized multiple times\n");
1985                 return 0;
1986         }
1987
1988         symbol_conf.priv_size += sizeof(struct annotation);
1989         symbol_conf.init_annotation = true;
1990         return 0;
1991 }
1992
1993 int symbol__init(struct perf_env *env)
1994 {
1995         const char *symfs;
1996
1997         if (symbol_conf.initialized)
1998                 return 0;
1999
2000         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2001
2002         symbol__elf_init();
2003
2004         if (symbol_conf.sort_by_name)
2005                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2006                                           sizeof(struct symbol));
2007
2008         if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2009                 return -1;
2010
2011         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2012                 pr_err("'.' is the only non valid --field-separator argument\n");
2013                 return -1;
2014         }
2015
2016         if (setup_list(&symbol_conf.dso_list,
2017                        symbol_conf.dso_list_str, "dso") < 0)
2018                 return -1;
2019
2020         if (setup_list(&symbol_conf.comm_list,
2021                        symbol_conf.comm_list_str, "comm") < 0)
2022                 goto out_free_dso_list;
2023
2024         if (setup_intlist(&symbol_conf.pid_list,
2025                        symbol_conf.pid_list_str, "pid") < 0)
2026                 goto out_free_comm_list;
2027
2028         if (setup_intlist(&symbol_conf.tid_list,
2029                        symbol_conf.tid_list_str, "tid") < 0)
2030                 goto out_free_pid_list;
2031
2032         if (setup_list(&symbol_conf.sym_list,
2033                        symbol_conf.sym_list_str, "symbol") < 0)
2034                 goto out_free_tid_list;
2035
2036         /*
2037          * A path to symbols of "/" is identical to ""
2038          * reset here for simplicity.
2039          */
2040         symfs = realpath(symbol_conf.symfs, NULL);
2041         if (symfs == NULL)
2042                 symfs = symbol_conf.symfs;
2043         if (strcmp(symfs, "/") == 0)
2044                 symbol_conf.symfs = "";
2045         if (symfs != symbol_conf.symfs)
2046                 free((void *)symfs);
2047
2048         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2049
2050         symbol_conf.initialized = true;
2051         return 0;
2052
2053 out_free_tid_list:
2054         intlist__delete(symbol_conf.tid_list);
2055 out_free_pid_list:
2056         intlist__delete(symbol_conf.pid_list);
2057 out_free_comm_list:
2058         strlist__delete(symbol_conf.comm_list);
2059 out_free_dso_list:
2060         strlist__delete(symbol_conf.dso_list);
2061         return -1;
2062 }
2063
2064 void symbol__exit(void)
2065 {
2066         if (!symbol_conf.initialized)
2067                 return;
2068         strlist__delete(symbol_conf.sym_list);
2069         strlist__delete(symbol_conf.dso_list);
2070         strlist__delete(symbol_conf.comm_list);
2071         intlist__delete(symbol_conf.tid_list);
2072         intlist__delete(symbol_conf.pid_list);
2073         vmlinux_path__exit();
2074         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2075         symbol_conf.initialized = false;
2076 }
2077
2078 int symbol__config_symfs(const struct option *opt __maybe_unused,
2079                          const char *dir, int unset __maybe_unused)
2080 {
2081         char *bf = NULL;
2082         int ret;
2083
2084         symbol_conf.symfs = strdup(dir);
2085         if (symbol_conf.symfs == NULL)
2086                 return -ENOMEM;
2087
2088         /* skip the locally configured cache if a symfs is given, and
2089          * config buildid dir to symfs/.debug
2090          */
2091         ret = asprintf(&bf, "%s/%s", dir, ".debug");
2092         if (ret < 0)
2093                 return -ENOMEM;
2094
2095         set_buildid_dir(bf);
2096
2097         free(bf);
2098         return 0;
2099 }