tools/bpf/resolve_btfids/main.c

   1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
   2
   3 /*
   4  * resolve_btfids scans Elf object for .BTF_ids section and resolves
   5  * its symbols with BTF ID values.
   6  *
   7  * Each symbol points to 4 bytes data and is expected to have
   8  * following name syntax:
   9  *
  10  * __BTF_ID__<type>__<symbol>[__<id>]
  11  *
  12  * type is:
  13  *
  14  *   func    - lookup BTF_KIND_FUNC symbol with <symbol> name
  15  *             and store its ID into the data:
  16  *
  17  *             __BTF_ID__func__vfs_close__1:
  18  *             .zero 4
  19  *
  20  *   struct  - lookup BTF_KIND_STRUCT symbol with <symbol> name
  21  *             and store its ID into the data:
  22  *
  23  *             __BTF_ID__struct__sk_buff__1:
  24  *             .zero 4
  25  *
  26  *   union   - lookup BTF_KIND_UNION symbol with <symbol> name
  27  *             and store its ID into the data:
  28  *
  29  *             __BTF_ID__union__thread_union__1:
  30  *             .zero 4
  31  *
  32  *   typedef - lookup BTF_KIND_TYPEDEF symbol with <symbol> name
  33  *             and store its ID into the data:
  34  *
  35  *             __BTF_ID__typedef__pid_t__1:
  36  *             .zero 4
  37  *
  38  *   set     - store symbol size into first 4 bytes and sort following
  39  *             ID list
  40  *
  41  *             __BTF_ID__set__list:
  42  *             .zero 4
  43  *             list:
  44  *             __BTF_ID__func__vfs_getattr__3:
  45  *             .zero 4
  46  *             __BTF_ID__func__vfs_fallocate__4:
  47  *             .zero 4
  48  *
  49  *   set8    - store symbol size into first 4 bytes and sort following
  50  *             ID list
  51  *
  52  *             __BTF_ID__set8__list:
  53  *             .zero 8
  54  *             list:
  55  *             __BTF_ID__func__vfs_getattr__3:
  56  *             .zero 4
  57  *             .word (1 << 0) | (1 << 2)
  58  *             __BTF_ID__func__vfs_fallocate__5:
  59  *             .zero 4
  60  *             .word (1 << 3) | (1 << 1) | (1 << 2)
  61  */
  62
  63 #define  _GNU_SOURCE
  64 #include <stdio.h>
  65 #include <string.h>
  66 #include <unistd.h>
  67 #include <stdlib.h>
  68 #include <libelf.h>
  69 #include <gelf.h>
  70 #include <sys/stat.h>
  71 #include <fcntl.h>
  72 #include <errno.h>
  73 #include <linux/rbtree.h>
  74 #include <linux/zalloc.h>
  75 #include <linux/err.h>
  76 #include <bpf/btf.h>
  77 #include <bpf/libbpf.h>
  78 #include <parse-options.h>
  79
  80 #define BTF_IDS_SECTION ".BTF_ids"
  81 #define BTF_ID          "__BTF_ID__"
  82
  83 #define BTF_STRUCT      "struct"
  84 #define BTF_UNION       "union"
  85 #define BTF_TYPEDEF     "typedef"
  86 #define BTF_FUNC        "func"
  87 #define BTF_SET         "set"
  88 #define BTF_SET8        "set8"
  89
  90 #define ADDR_CNT        100
  91
  92 struct btf_id {
  93         struct rb_node   rb_node;
  94         char            *name;
  95         union {
  96                 int      id;
  97                 int      cnt;
  98         };
  99         int              addr_cnt;
 100         bool             is_set;
 101         bool             is_set8;
 102         Elf64_Addr       addr[ADDR_CNT];
 103 };
 104
 105 struct object {
 106         const char *path;
 107         const char *btf;
 108         const char *base_btf_path;
 109
 110         struct {
 111                 int              fd;
 112                 Elf             *elf;
 113                 Elf_Data        *symbols;
 114                 Elf_Data        *idlist;
 115                 int              symbols_shndx;
 116                 int              idlist_shndx;
 117                 size_t           strtabidx;
 118                 unsigned long    idlist_addr;
 119         } efile;
 120
 121         struct rb_root  sets;
 122         struct rb_root  structs;
 123         struct rb_root  unions;
 124         struct rb_root  typedefs;
 125         struct rb_root  funcs;
 126
 127         int nr_funcs;
 128         int nr_structs;
 129         int nr_unions;
 130         int nr_typedefs;
 131 };
 132
 133 static int verbose;
 134
 135 static int eprintf(int level, int var, const char *fmt, ...)
 136 {
 137         va_list args;
 138         int ret = 0;
 139
 140         if (var >= level) {
 141                 va_start(args, fmt);
 142                 ret = vfprintf(stderr, fmt, args);
 143                 va_end(args);
 144         }
 145         return ret;
 146 }
 147
 148 #ifndef pr_fmt
 149 #define pr_fmt(fmt) fmt
 150 #endif
 151
 152 #define pr_debug(fmt, ...) \
 153         eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__)
 154 #define pr_debugN(n, fmt, ...) \
 155         eprintf(n, verbose, pr_fmt(fmt), ##__VA_ARGS__)
 156 #define pr_debug2(fmt, ...) pr_debugN(2, pr_fmt(fmt), ##__VA_ARGS__)
 157 #define pr_err(fmt, ...) \
 158         eprintf(0, verbose, pr_fmt(fmt), ##__VA_ARGS__)
 159 #define pr_info(fmt, ...) \
 160         eprintf(0, verbose, pr_fmt(fmt), ##__VA_ARGS__)
 161
 162 static bool is_btf_id(const char *name)
 163 {
 164         return name && !strncmp(name, BTF_ID, sizeof(BTF_ID) - 1);
 165 }
 166
 167 static struct btf_id *btf_id__find(struct rb_root *root, const char *name)
 168 {
 169         struct rb_node *p = root->rb_node;
 170         struct btf_id *id;
 171         int cmp;
 172
 173         while (p) {
 174                 id = rb_entry(p, struct btf_id, rb_node);
 175                 cmp = strcmp(id->name, name);
 176                 if (cmp < 0)
 177                         p = p->rb_left;
 178                 else if (cmp > 0)
 179                         p = p->rb_right;
 180                 else
 181                         return id;
 182         }
 183         return NULL;
 184 }
 185
 186 static struct btf_id *
 187 btf_id__add(struct rb_root *root, char *name, bool unique)
 188 {
 189         struct rb_node **p = &root->rb_node;
 190         struct rb_node *parent = NULL;
 191         struct btf_id *id;
 192         int cmp;
 193
 194         while (*p != NULL) {
 195                 parent = *p;
 196                 id = rb_entry(parent, struct btf_id, rb_node);
 197                 cmp = strcmp(id->name, name);
 198                 if (cmp < 0)
 199                         p = &(*p)->rb_left;
 200                 else if (cmp > 0)
 201                         p = &(*p)->rb_right;
 202                 else
 203                         return unique ? NULL : id;
 204         }
 205
 206         id = zalloc(sizeof(*id));
 207         if (id) {
 208                 pr_debug("adding symbol %s\n", name);
 209                 id->name = name;
 210                 rb_link_node(&id->rb_node, parent, p);
 211                 rb_insert_color(&id->rb_node, root);
 212         }
 213         return id;
 214 }
 215
 216 static char *get_id(const char *prefix_end)
 217 {
 218         /*
 219          * __BTF_ID__func__vfs_truncate__0
 220          * prefix_end =  ^
 221          * pos        =    ^
 222          */
 223         int len = strlen(prefix_end);
 224         int pos = sizeof("__") - 1;
 225         char *p, *id;
 226
 227         if (pos >= len)
 228                 return NULL;
 229
 230         id = strdup(prefix_end + pos);
 231         if (id) {
 232                 /*
 233                  * __BTF_ID__func__vfs_truncate__0
 234                  * id =            ^
 235                  *
 236                  * cut the unique id part
 237                  */
 238                 p = strrchr(id, '_');
 239                 p--;
 240                 if (*p != '_') {
 241                         free(id);
 242                         return NULL;
 243                 }
 244                 *p = '\0';
 245         }
 246         return id;
 247 }
 248
 249 static struct btf_id *add_set(struct object *obj, char *name, bool is_set8)
 250 {
 251         /*
 252          * __BTF_ID__set__name
 253          * name =    ^
 254          * id   =         ^
 255          */
 256         char *id = name + (is_set8 ? sizeof(BTF_SET8 "__") : sizeof(BTF_SET "__")) - 1;
 257         int len = strlen(name);
 258
 259         if (id >= name + len) {
 260                 pr_err("FAILED to parse set name: %s\n", name);
 261                 return NULL;
 262         }
 263
 264         return btf_id__add(&obj->sets, id, true);
 265 }
 266
 267 static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size)
 268 {
 269         char *id;
 270
 271         id = get_id(name + size);
 272         if (!id) {
 273                 pr_err("FAILED to parse symbol name: %s\n", name);
 274                 return NULL;
 275         }
 276
 277         return btf_id__add(root, id, false);
 278 }
 279
 280 /* Older libelf.h and glibc elf.h might not yet define the ELF compression types. */
 281 #ifndef SHF_COMPRESSED
 282 #define SHF_COMPRESSED (1 << 11) /* Section with compressed data. */
 283 #endif
 284
 285 /*
 286  * The data of compressed section should be aligned to 4
 287  * (for 32bit) or 8 (for 64 bit) bytes. The binutils ld
 288  * sets sh_addralign to 1, which makes libelf fail with
 289  * misaligned section error during the update:
 290  *    FAILED elf_update(WRITE): invalid section alignment
 291  *
 292  * While waiting for ld fix, we fix the compressed sections
 293  * sh_addralign value manualy.
 294  */
 295 static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh)
 296 {
 297         int expected = gelf_getclass(elf) == ELFCLASS32 ? 4 : 8;
 298
 299         if (!(sh->sh_flags & SHF_COMPRESSED))
 300                 return 0;
 301
 302         if (sh->sh_addralign == expected)
 303                 return 0;
 304
 305         pr_debug2(" - fixing wrong alignment sh_addralign %u, expected %u\n",
 306                   sh->sh_addralign, expected);
 307
 308         sh->sh_addralign = expected;
 309
 310         if (gelf_update_shdr(scn, sh) == 0) {
 311                 pr_err("FAILED cannot update section header: %s\n",
 312                         elf_errmsg(-1));
 313                 return -1;
 314         }
 315         return 0;
 316 }
 317
 318 static int elf_collect(struct object *obj)
 319 {
 320         Elf_Scn *scn = NULL;
 321         size_t shdrstrndx;
 322         int idx = 0;
 323         Elf *elf;
 324         int fd;
 325
 326         fd = open(obj->path, O_RDWR, 0666);
 327         if (fd == -1) {
 328                 pr_err("FAILED cannot open %s: %s\n",
 329                         obj->path, strerror(errno));
 330                 return -1;
 331         }
 332
 333         elf_version(EV_CURRENT);
 334
 335         elf = elf_begin(fd, ELF_C_RDWR_MMAP, NULL);
 336         if (!elf) {
 337                 close(fd);
 338                 pr_err("FAILED cannot create ELF descriptor: %s\n",
 339                         elf_errmsg(-1));
 340                 return -1;
 341         }
 342
 343         obj->efile.fd  = fd;
 344         obj->efile.elf = elf;
 345
 346         elf_flagelf(elf, ELF_C_SET, ELF_F_LAYOUT);
 347
 348         if (elf_getshdrstrndx(elf, &shdrstrndx) != 0) {
 349                 pr_err("FAILED cannot get shdr str ndx\n");
 350                 return -1;
 351         }
 352
 353         /*
 354          * Scan all the elf sections and look for save data
 355          * from .BTF_ids section and symbols.
 356          */
 357         while ((scn = elf_nextscn(elf, scn)) != NULL) {
 358                 Elf_Data *data;
 359                 GElf_Shdr sh;
 360                 char *name;
 361
 362                 idx++;
 363                 if (gelf_getshdr(scn, &sh) != &sh) {
 364                         pr_err("FAILED get section(%d) header\n", idx);
 365                         return -1;
 366                 }
 367
 368                 name = elf_strptr(elf, shdrstrndx, sh.sh_name);
 369                 if (!name) {
 370                         pr_err("FAILED get section(%d) name\n", idx);
 371                         return -1;
 372                 }
 373
 374                 data = elf_getdata(scn, 0);
 375                 if (!data) {
 376                         pr_err("FAILED to get section(%d) data from %s\n",
 377                                 idx, name);
 378                         return -1;
 379                 }
 380
 381                 pr_debug2("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n",
 382                           idx, name, (unsigned long) data->d_size,
 383                           (int) sh.sh_link, (unsigned long) sh.sh_flags,
 384                           (int) sh.sh_type);
 385
 386                 if (sh.sh_type == SHT_SYMTAB) {
 387                         obj->efile.symbols       = data;
 388                         obj->efile.symbols_shndx = idx;
 389                         obj->efile.strtabidx     = sh.sh_link;
 390                 } else if (!strcmp(name, BTF_IDS_SECTION)) {
 391                         obj->efile.idlist       = data;
 392                         obj->efile.idlist_shndx = idx;
 393                         obj->efile.idlist_addr  = sh.sh_addr;
 394                 }
 395
 396                 if (compressed_section_fix(elf, scn, &sh))
 397                         return -1;
 398         }
 399
 400         return 0;
 401 }
 402
 403 static int symbols_collect(struct object *obj)
 404 {
 405         Elf_Scn *scn = NULL;
 406         int n, i;
 407         GElf_Shdr sh;
 408         char *name;
 409
 410         scn = elf_getscn(obj->efile.elf, obj->efile.symbols_shndx);
 411         if (!scn)
 412                 return -1;
 413
 414         if (gelf_getshdr(scn, &sh) != &sh)
 415                 return -1;
 416
 417         n = sh.sh_size / sh.sh_entsize;
 418
 419         /*
 420          * Scan symbols and look for the ones starting with
 421          * __BTF_ID__* over .BTF_ids section.
 422          */
 423         for (i = 0; i < n; i++) {
 424                 char *prefix;
 425                 struct btf_id *id;
 426                 GElf_Sym sym;
 427
 428                 if (!gelf_getsym(obj->efile.symbols, i, &sym))
 429                         return -1;
 430
 431                 if (sym.st_shndx != obj->efile.idlist_shndx)
 432                         continue;
 433
 434                 name = elf_strptr(obj->efile.elf, obj->efile.strtabidx,
 435                                   sym.st_name);
 436
 437                 if (!is_btf_id(name))
 438                         continue;
 439
 440                 /*
 441                  * __BTF_ID__TYPE__vfs_truncate__0
 442                  * prefix =  ^
 443                  */
 444                 prefix = name + sizeof(BTF_ID) - 1;
 445
 446                 /* struct */
 447                 if (!strncmp(prefix, BTF_STRUCT, sizeof(BTF_STRUCT) - 1)) {
 448                         obj->nr_structs++;
 449                         id = add_symbol(&obj->structs, prefix, sizeof(BTF_STRUCT) - 1);
 450                 /* union  */
 451                 } else if (!strncmp(prefix, BTF_UNION, sizeof(BTF_UNION) - 1)) {
 452                         obj->nr_unions++;
 453                         id = add_symbol(&obj->unions, prefix, sizeof(BTF_UNION) - 1);
 454                 /* typedef */
 455                 } else if (!strncmp(prefix, BTF_TYPEDEF, sizeof(BTF_TYPEDEF) - 1)) {
 456                         obj->nr_typedefs++;
 457                         id = add_symbol(&obj->typedefs, prefix, sizeof(BTF_TYPEDEF) - 1);
 458                 /* func */
 459                 } else if (!strncmp(prefix, BTF_FUNC, sizeof(BTF_FUNC) - 1)) {
 460                         obj->nr_funcs++;
 461                         id = add_symbol(&obj->funcs, prefix, sizeof(BTF_FUNC) - 1);
 462                 /* set8 */
 463                 } else if (!strncmp(prefix, BTF_SET8, sizeof(BTF_SET8) - 1)) {
 464                         id = add_set(obj, prefix, true);
 465                         /*
 466                          * SET8 objects store list's count, which is encoded
 467                          * in symbol's size, together with 'cnt' field hence
 468                          * that - 1.
 469                          */
 470                         if (id) {
 471                                 id->cnt = sym.st_size / sizeof(uint64_t) - 1;
 472                                 id->is_set8 = true;
 473                         }
 474                 /* set */
 475                 } else if (!strncmp(prefix, BTF_SET, sizeof(BTF_SET) - 1)) {
 476                         id = add_set(obj, prefix, false);
 477                         /*
 478                          * SET objects store list's count, which is encoded
 479                          * in symbol's size, together with 'cnt' field hence
 480                          * that - 1.
 481                          */
 482                         if (id) {
 483                                 id->cnt = sym.st_size / sizeof(int) - 1;
 484                                 id->is_set = true;
 485                         }
 486                 } else {
 487                         pr_err("FAILED unsupported prefix %s\n", prefix);
 488                         return -1;
 489                 }
 490
 491                 if (!id)
 492                         return -ENOMEM;
 493
 494                 if (id->addr_cnt >= ADDR_CNT) {
 495                         pr_err("FAILED symbol %s crossed the number of allowed lists\n",
 496                                 id->name);
 497                         return -1;
 498                 }
 499                 id->addr[id->addr_cnt++] = sym.st_value;
 500         }
 501
 502         return 0;
 503 }
 504
 505 static int symbols_resolve(struct object *obj)
 506 {
 507         int nr_typedefs = obj->nr_typedefs;
 508         int nr_structs  = obj->nr_structs;
 509         int nr_unions   = obj->nr_unions;
 510         int nr_funcs    = obj->nr_funcs;
 511         struct btf *base_btf = NULL;
 512         int err, type_id;
 513         struct btf *btf;
 514         __u32 nr_types;
 515
 516         if (obj->base_btf_path) {
 517                 base_btf = btf__parse(obj->base_btf_path, NULL);
 518                 err = libbpf_get_error(base_btf);
 519                 if (err) {
 520                         pr_err("FAILED: load base BTF from %s: %s\n",
 521                                obj->base_btf_path, strerror(-err));
 522                         return -1;
 523                 }
 524         }
 525
 526         btf = btf__parse_split(obj->btf ?: obj->path, base_btf);
 527         err = libbpf_get_error(btf);
 528         if (err) {
 529                 pr_err("FAILED: load BTF from %s: %s\n",
 530                         obj->btf ?: obj->path, strerror(-err));
 531                 goto out;
 532         }
 533
 534         err = -1;
 535         nr_types = btf__type_cnt(btf);
 536
 537         /*
 538          * Iterate all the BTF types and search for collected symbol IDs.
 539          */
 540         for (type_id = 1; type_id < nr_types; type_id++) {
 541                 const struct btf_type *type;
 542                 struct rb_root *root;
 543                 struct btf_id *id;
 544                 const char *str;
 545                 int *nr;
 546
 547                 type = btf__type_by_id(btf, type_id);
 548                 if (!type) {
 549                         pr_err("FAILED: malformed BTF, can't resolve type for ID %d\n",
 550                                 type_id);
 551                         goto out;
 552                 }
 553
 554                 if (btf_is_func(type) && nr_funcs) {
 555                         nr   = &nr_funcs;
 556                         root = &obj->funcs;
 557                 } else if (btf_is_struct(type) && nr_structs) {
 558                         nr   = &nr_structs;
 559                         root = &obj->structs;
 560                 } else if (btf_is_union(type) && nr_unions) {
 561                         nr   = &nr_unions;
 562                         root = &obj->unions;
 563                 } else if (btf_is_typedef(type) && nr_typedefs) {
 564                         nr   = &nr_typedefs;
 565                         root = &obj->typedefs;
 566                 } else
 567                         continue;
 568
 569                 str = btf__name_by_offset(btf, type->name_off);
 570                 if (!str) {
 571                         pr_err("FAILED: malformed BTF, can't resolve name for ID %d\n",
 572                                 type_id);
 573                         goto out;
 574                 }
 575
 576                 id = btf_id__find(root, str);
 577                 if (id) {
 578                         if (id->id) {
 579                                 pr_info("WARN: multiple IDs found for '%s': %d, %d - using %d\n",
 580                                         str, id->id, type_id, id->id);
 581                         } else {
 582                                 id->id = type_id;
 583                                 (*nr)--;
 584                         }
 585                 }
 586         }
 587
 588         err = 0;
 589 out:
 590         btf__free(base_btf);
 591         btf__free(btf);
 592         return err;
 593 }
 594
 595 static int id_patch(struct object *obj, struct btf_id *id)
 596 {
 597         Elf_Data *data = obj->efile.idlist;
 598         int *ptr = data->d_buf;
 599         int i;
 600
 601         /* For set, set8, id->id may be 0 */
 602         if (!id->id && !id->is_set && !id->is_set8)
 603                 pr_err("WARN: resolve_btfids: unresolved symbol %s\n", id->name);
 604
 605         for (i = 0; i < id->addr_cnt; i++) {
 606                 unsigned long addr = id->addr[i];
 607                 unsigned long idx = addr - obj->efile.idlist_addr;
 608
 609                 pr_debug("patching addr %5lu: ID %7d [%s]\n",
 610                          idx, id->id, id->name);
 611
 612                 if (idx >= data->d_size) {
 613                         pr_err("FAILED patching index %lu out of bounds %lu\n",
 614                                 idx, data->d_size);
 615                         return -1;
 616                 }
 617
 618                 idx = idx / sizeof(int);
 619                 ptr[idx] = id->id;
 620         }
 621
 622         return 0;
 623 }
 624
 625 static int __symbols_patch(struct object *obj, struct rb_root *root)
 626 {
 627         struct rb_node *next;
 628         struct btf_id *id;
 629
 630         next = rb_first(root);
 631         while (next) {
 632                 id = rb_entry(next, struct btf_id, rb_node);
 633
 634                 if (id_patch(obj, id))
 635                         return -1;
 636
 637                 next = rb_next(next);
 638         }
 639         return 0;
 640 }
 641
 642 static int cmp_id(const void *pa, const void *pb)
 643 {
 644         const int *a = pa, *b = pb;
 645
 646         return *a - *b;
 647 }
 648
 649 static int sets_patch(struct object *obj)
 650 {
 651         Elf_Data *data = obj->efile.idlist;
 652         int *ptr = data->d_buf;
 653         struct rb_node *next;
 654
 655         next = rb_first(&obj->sets);
 656         while (next) {
 657                 unsigned long addr, idx;
 658                 struct btf_id *id;
 659                 int *base;
 660                 int cnt;
 661
 662                 id   = rb_entry(next, struct btf_id, rb_node);
 663                 addr = id->addr[0];
 664                 idx  = addr - obj->efile.idlist_addr;
 665
 666                 /* sets are unique */
 667                 if (id->addr_cnt != 1) {
 668                         pr_err("FAILED malformed data for set '%s'\n",
 669                                 id->name);
 670                         return -1;
 671                 }
 672
 673                 idx = idx / sizeof(int);
 674                 base = &ptr[idx] + (id->is_set8 ? 2 : 1);
 675                 cnt = ptr[idx];
 676
 677                 pr_debug("sorting  addr %5lu: cnt %6d [%s]\n",
 678                          (idx + 1) * sizeof(int), cnt, id->name);
 679
 680                 qsort(base, cnt, id->is_set8 ? sizeof(uint64_t) : sizeof(int), cmp_id);
 681
 682                 next = rb_next(next);
 683         }
 684         return 0;
 685 }
 686
 687 static int symbols_patch(struct object *obj)
 688 {
 689         int err;
 690
 691         if (__symbols_patch(obj, &obj->structs)  ||
 692             __symbols_patch(obj, &obj->unions)   ||
 693             __symbols_patch(obj, &obj->typedefs) ||
 694             __symbols_patch(obj, &obj->funcs)    ||
 695             __symbols_patch(obj, &obj->sets))
 696                 return -1;
 697
 698         if (sets_patch(obj))
 699                 return -1;
 700
 701         /* Set type to ensure endian translation occurs. */
 702         obj->efile.idlist->d_type = ELF_T_WORD;
 703
 704         elf_flagdata(obj->efile.idlist, ELF_C_SET, ELF_F_DIRTY);
 705
 706         err = elf_update(obj->efile.elf, ELF_C_WRITE);
 707         if (err < 0) {
 708                 pr_err("FAILED elf_update(WRITE): %s\n",
 709                         elf_errmsg(-1));
 710         }
 711
 712         pr_debug("update %s for %s\n",
 713                  err >= 0 ? "ok" : "failed", obj->path);
 714         return err < 0 ? -1 : 0;
 715 }
 716
 717 static const char * const resolve_btfids_usage[] = {
 718         "resolve_btfids [<options>] <ELF object>",
 719         NULL
 720 };
 721
 722 int main(int argc, const char **argv)
 723 {
 724         struct object obj = {
 725                 .efile = {
 726                         .idlist_shndx  = -1,
 727                         .symbols_shndx = -1,
 728                 },
 729                 .structs  = RB_ROOT,
 730                 .unions   = RB_ROOT,
 731                 .typedefs = RB_ROOT,
 732                 .funcs    = RB_ROOT,
 733                 .sets     = RB_ROOT,
 734         };
 735         struct option btfid_options[] = {
 736                 OPT_INCR('v', "verbose", &verbose,
 737                          "be more verbose (show errors, etc)"),
 738                 OPT_STRING(0, "btf", &obj.btf, "BTF data",
 739                            "BTF data"),
 740                 OPT_STRING('b', "btf_base", &obj.base_btf_path, "file",
 741                            "path of file providing base BTF"),
 742                 OPT_END()
 743         };
 744         int err = -1;
 745
 746         argc = parse_options(argc, argv, btfid_options, resolve_btfids_usage,
 747                              PARSE_OPT_STOP_AT_NON_OPTION);
 748         if (argc != 1)
 749                 usage_with_options(resolve_btfids_usage, btfid_options);
 750
 751         obj.path = argv[0];
 752
 753         if (elf_collect(&obj))
 754                 goto out;
 755
 756         /*
 757          * We did not find .BTF_ids section or symbols section,
 758          * nothing to do..
 759          */
 760         if (obj.efile.idlist_shndx == -1 ||
 761             obj.efile.symbols_shndx == -1) {
 762                 pr_debug("Cannot find .BTF_ids or symbols sections, nothing to do\n");
 763                 err = 0;
 764                 goto out;
 765         }
 766
 767         if (symbols_collect(&obj))
 768                 goto out;
 769
 770         if (symbols_resolve(&obj))
 771                 goto out;
 772
 773         if (symbols_patch(&obj))
 774                 goto out;
 775
 776         err = 0;
 777 out:
 778         if (obj.efile.elf) {
 779                 elf_end(obj.efile.elf);
 780                 close(obj.efile.fd);
 781         }
 782         return err;
 783 }