1 /* Generate assembler source containing symbol information 2 * 3 * Copyright 2002 by Kai Germaschewski 4 * 5 * This software may be used and distributed according to the terms 6 * of the GNU General Public License, incorporated herein by reference. 7 * 8 * Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S 9 * 10 * Table compression uses all the unused char codes on the symbols and 11 * maps these to the most used substrings (tokens). For instance, it might 12 * map char code 0xF7 to represent "write_" and then in every symbol where 13 * "write_" appears it can be replaced by 0xF7, saving 5 bytes. 14 * The used codes themselves are also placed in the table so that the 15 * decompresion can work without "special cases". 16 * Applied to kernel symbols, this usually produces a compression ratio 17 * of about 50%. 18 * 19 */ 20 21 #include <stdbool.h> 22 #include <stdio.h> 23 #include <stdlib.h> 24 #include <string.h> 25 #include <ctype.h> 26 #include <limits.h> 27 28 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) 29 30 #define _stringify_1(x) #x 31 #define _stringify(x) _stringify_1(x) 32 33 #define KSYM_NAME_LEN 512 34 35 /* 36 * A substantially bigger size than the current maximum. 37 * 38 * It cannot be defined as an expression because it gets stringified 39 * for the fscanf() format string. Therefore, a _Static_assert() is 40 * used instead to maintain the relationship with KSYM_NAME_LEN. 41 */ 42 #define KSYM_NAME_LEN_BUFFER 2048 43 _Static_assert( 44 KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4, 45 "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN" 46 ); 47 48 struct sym_entry { 49 unsigned long long addr; 50 unsigned int len; 51 unsigned int start_pos; 52 unsigned int percpu_absolute; 53 unsigned char sym[]; 54 }; 55 56 struct addr_range { 57 const char *start_sym, *end_sym; 58 unsigned long long start, end; 59 }; 60 61 static unsigned long long _text; 62 static unsigned long long relative_base; 63 static struct addr_range text_ranges[] = { 64 { "_stext", "_etext" }, 65 { "_sinittext", "_einittext" }, 66 }; 67 #define text_range_text (&text_ranges[0]) 68 #define text_range_inittext (&text_ranges[1]) 69 70 static struct addr_range percpu_range = { 71 "__per_cpu_start", "__per_cpu_end", -1ULL, 0 72 }; 73 74 static struct sym_entry **table; 75 static unsigned int table_size, table_cnt; 76 static int all_symbols; 77 static int absolute_percpu; 78 static int base_relative; 79 80 static int token_profit[0x10000]; 81 82 /* the table that holds the result of the compression */ 83 static unsigned char best_table[256][2]; 84 static unsigned char best_table_len[256]; 85 86 87 static void usage(void) 88 { 89 fprintf(stderr, "Usage: kallsyms [--all-symbols] [--absolute-percpu] " 90 "[--base-relative] < in.map > out.S\n"); 91 exit(1); 92 } 93 94 static char *sym_name(const struct sym_entry *s) 95 { 96 return (char *)s->sym + 1; 97 } 98 99 static bool is_ignored_symbol(const char *name, char type) 100 { 101 /* Symbol names that exactly match to the following are ignored.*/ 102 static const char * const ignored_symbols[] = { 103 /* 104 * Symbols which vary between passes. Passes 1 and 2 must have 105 * identical symbol lists. The kallsyms_* symbols below are 106 * only added after pass 1, they would be included in pass 2 107 * when --all-symbols is specified so exclude them to get a 108 * stable symbol list. 109 */ 110 "kallsyms_addresses", 111 "kallsyms_offsets", 112 "kallsyms_relative_base", 113 "kallsyms_num_syms", 114 "kallsyms_names", 115 "kallsyms_markers", 116 "kallsyms_token_table", 117 "kallsyms_token_index", 118 /* Exclude linker generated symbols which vary between passes */ 119 "_SDA_BASE_", /* ppc */ 120 "_SDA2_BASE_", /* ppc */ 121 NULL 122 }; 123 124 /* Symbol names that begin with the following are ignored.*/ 125 static const char * const ignored_prefixes[] = { 126 "$", /* local symbols for ARM, MIPS, etc. */ 127 ".L", /* local labels, .LBB,.Ltmpxxx,.L__unnamed_xx,.LASANPC, etc. */ 128 "__crc_", /* modversions */ 129 "__efistub_", /* arm64 EFI stub namespace */ 130 "__kvm_nvhe_$", /* arm64 local symbols in non-VHE KVM namespace */ 131 "__kvm_nvhe_.L", /* arm64 local symbols in non-VHE KVM namespace */ 132 "__AArch64ADRPThunk_", /* arm64 lld */ 133 "__ARMV5PILongThunk_", /* arm lld */ 134 "__ARMV7PILongThunk_", 135 "__ThumbV7PILongThunk_", 136 "__LA25Thunk_", /* mips lld */ 137 "__microLA25Thunk_", 138 "__kcfi_typeid_", /* CFI type identifiers */ 139 NULL 140 }; 141 142 /* Symbol names that end with the following are ignored.*/ 143 static const char * const ignored_suffixes[] = { 144 "_from_arm", /* arm */ 145 "_from_thumb", /* arm */ 146 "_veneer", /* arm */ 147 NULL 148 }; 149 150 /* Symbol names that contain the following are ignored.*/ 151 static const char * const ignored_matches[] = { 152 ".long_branch.", /* ppc stub */ 153 ".plt_branch.", /* ppc stub */ 154 NULL 155 }; 156 157 const char * const *p; 158 159 for (p = ignored_symbols; *p; p++) 160 if (!strcmp(name, *p)) 161 return true; 162 163 for (p = ignored_prefixes; *p; p++) 164 if (!strncmp(name, *p, strlen(*p))) 165 return true; 166 167 for (p = ignored_suffixes; *p; p++) { 168 int l = strlen(name) - strlen(*p); 169 170 if (l >= 0 && !strcmp(name + l, *p)) 171 return true; 172 } 173 174 for (p = ignored_matches; *p; p++) { 175 if (strstr(name, *p)) 176 return true; 177 } 178 179 if (type == 'U' || type == 'u') 180 return true; 181 /* exclude debugging symbols */ 182 if (type == 'N' || type == 'n') 183 return true; 184 185 if (toupper(type) == 'A') { 186 /* Keep these useful absolute symbols */ 187 if (strcmp(name, "__kernel_syscall_via_break") && 188 strcmp(name, "__kernel_syscall_via_epc") && 189 strcmp(name, "__kernel_sigtramp") && 190 strcmp(name, "__gp")) 191 return true; 192 } 193 194 return false; 195 } 196 197 static void check_symbol_range(const char *sym, unsigned long long addr, 198 struct addr_range *ranges, int entries) 199 { 200 size_t i; 201 struct addr_range *ar; 202 203 for (i = 0; i < entries; ++i) { 204 ar = &ranges[i]; 205 206 if (strcmp(sym, ar->start_sym) == 0) { 207 ar->start = addr; 208 return; 209 } else if (strcmp(sym, ar->end_sym) == 0) { 210 ar->end = addr; 211 return; 212 } 213 } 214 } 215 216 static struct sym_entry *read_symbol(FILE *in) 217 { 218 char name[KSYM_NAME_LEN_BUFFER+1], type; 219 unsigned long long addr; 220 unsigned int len; 221 struct sym_entry *sym; 222 int rc; 223 224 rc = fscanf(in, "%llx %c %" _stringify(KSYM_NAME_LEN_BUFFER) "s\n", &addr, &type, name); 225 if (rc != 3) { 226 if (rc != EOF && fgets(name, ARRAY_SIZE(name), in) == NULL) 227 fprintf(stderr, "Read error or end of file.\n"); 228 return NULL; 229 } 230 if (strlen(name) >= KSYM_NAME_LEN) { 231 fprintf(stderr, "Symbol %s too long for kallsyms (%zu >= %d).\n" 232 "Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n", 233 name, strlen(name), KSYM_NAME_LEN); 234 return NULL; 235 } 236 237 if (strcmp(name, "_text") == 0) 238 _text = addr; 239 240 /* Ignore most absolute/undefined (?) symbols. */ 241 if (is_ignored_symbol(name, type)) 242 return NULL; 243 244 check_symbol_range(name, addr, text_ranges, ARRAY_SIZE(text_ranges)); 245 check_symbol_range(name, addr, &percpu_range, 1); 246 247 /* include the type field in the symbol name, so that it gets 248 * compressed together */ 249 250 len = strlen(name) + 1; 251 252 sym = malloc(sizeof(*sym) + len + 1); 253 if (!sym) { 254 fprintf(stderr, "kallsyms failure: " 255 "unable to allocate required amount of memory\n"); 256 exit(EXIT_FAILURE); 257 } 258 sym->addr = addr; 259 sym->len = len; 260 sym->sym[0] = type; 261 strcpy(sym_name(sym), name); 262 sym->percpu_absolute = 0; 263 264 return sym; 265 } 266 267 static int symbol_in_range(const struct sym_entry *s, 268 const struct addr_range *ranges, int entries) 269 { 270 size_t i; 271 const struct addr_range *ar; 272 273 for (i = 0; i < entries; ++i) { 274 ar = &ranges[i]; 275 276 if (s->addr >= ar->start && s->addr <= ar->end) 277 return 1; 278 } 279 280 return 0; 281 } 282 283 static int symbol_valid(const struct sym_entry *s) 284 { 285 const char *name = sym_name(s); 286 287 /* if --all-symbols is not specified, then symbols outside the text 288 * and inittext sections are discarded */ 289 if (!all_symbols) { 290 if (symbol_in_range(s, text_ranges, 291 ARRAY_SIZE(text_ranges)) == 0) 292 return 0; 293 /* Corner case. Discard any symbols with the same value as 294 * _etext _einittext; they can move between pass 1 and 2 when 295 * the kallsyms data are added. If these symbols move then 296 * they may get dropped in pass 2, which breaks the kallsyms 297 * rules. 298 */ 299 if ((s->addr == text_range_text->end && 300 strcmp(name, text_range_text->end_sym)) || 301 (s->addr == text_range_inittext->end && 302 strcmp(name, text_range_inittext->end_sym))) 303 return 0; 304 } 305 306 return 1; 307 } 308 309 /* remove all the invalid symbols from the table */ 310 static void shrink_table(void) 311 { 312 unsigned int i, pos; 313 314 pos = 0; 315 for (i = 0; i < table_cnt; i++) { 316 if (symbol_valid(table[i])) { 317 if (pos != i) 318 table[pos] = table[i]; 319 pos++; 320 } else { 321 free(table[i]); 322 } 323 } 324 table_cnt = pos; 325 326 /* When valid symbol is not registered, exit to error */ 327 if (!table_cnt) { 328 fprintf(stderr, "No valid symbol.\n"); 329 exit(1); 330 } 331 } 332 333 static void read_map(FILE *in) 334 { 335 struct sym_entry *sym; 336 337 while (!feof(in)) { 338 sym = read_symbol(in); 339 if (!sym) 340 continue; 341 342 sym->start_pos = table_cnt; 343 344 if (table_cnt >= table_size) { 345 table_size += 10000; 346 table = realloc(table, sizeof(*table) * table_size); 347 if (!table) { 348 fprintf(stderr, "out of memory\n"); 349 exit (1); 350 } 351 } 352 353 table[table_cnt++] = sym; 354 } 355 } 356 357 static void output_label(const char *label) 358 { 359 printf(".globl %s\n", label); 360 printf("\tALGN\n"); 361 printf("%s:\n", label); 362 } 363 364 /* Provide proper symbols relocatability by their '_text' relativeness. */ 365 static void output_address(unsigned long long addr) 366 { 367 if (_text <= addr) 368 printf("\tPTR\t_text + %#llx\n", addr - _text); 369 else 370 printf("\tPTR\t_text - %#llx\n", _text - addr); 371 } 372 373 /* uncompress a compressed symbol. When this function is called, the best table 374 * might still be compressed itself, so the function needs to be recursive */ 375 static int expand_symbol(const unsigned char *data, int len, char *result) 376 { 377 int c, rlen, total=0; 378 379 while (len) { 380 c = *data; 381 /* if the table holds a single char that is the same as the one 382 * we are looking for, then end the search */ 383 if (best_table[c][0]==c && best_table_len[c]==1) { 384 *result++ = c; 385 total++; 386 } else { 387 /* if not, recurse and expand */ 388 rlen = expand_symbol(best_table[c], best_table_len[c], result); 389 total += rlen; 390 result += rlen; 391 } 392 data++; 393 len--; 394 } 395 *result=0; 396 397 return total; 398 } 399 400 static int symbol_absolute(const struct sym_entry *s) 401 { 402 return s->percpu_absolute; 403 } 404 405 static void write_src(void) 406 { 407 unsigned int i, k, off; 408 unsigned int best_idx[256]; 409 unsigned int *markers; 410 char buf[KSYM_NAME_LEN]; 411 412 printf("#include <asm/bitsperlong.h>\n"); 413 printf("#if BITS_PER_LONG == 64\n"); 414 printf("#define PTR .quad\n"); 415 printf("#define ALGN .balign 8\n"); 416 printf("#else\n"); 417 printf("#define PTR .long\n"); 418 printf("#define ALGN .balign 4\n"); 419 printf("#endif\n"); 420 421 printf("\t.section .rodata, \"a\"\n"); 422 423 if (!base_relative) 424 output_label("kallsyms_addresses"); 425 else 426 output_label("kallsyms_offsets"); 427 428 for (i = 0; i < table_cnt; i++) { 429 if (base_relative) { 430 /* 431 * Use the offset relative to the lowest value 432 * encountered of all relative symbols, and emit 433 * non-relocatable fixed offsets that will be fixed 434 * up at runtime. 435 */ 436 437 long long offset; 438 int overflow; 439 440 if (!absolute_percpu) { 441 offset = table[i]->addr - relative_base; 442 overflow = (offset < 0 || offset > UINT_MAX); 443 } else if (symbol_absolute(table[i])) { 444 offset = table[i]->addr; 445 overflow = (offset < 0 || offset > INT_MAX); 446 } else { 447 offset = relative_base - table[i]->addr - 1; 448 overflow = (offset < INT_MIN || offset >= 0); 449 } 450 if (overflow) { 451 fprintf(stderr, "kallsyms failure: " 452 "%s symbol value %#llx out of range in relative mode\n", 453 symbol_absolute(table[i]) ? "absolute" : "relative", 454 table[i]->addr); 455 exit(EXIT_FAILURE); 456 } 457 printf("\t.long\t%#x\n", (int)offset); 458 } else if (!symbol_absolute(table[i])) { 459 output_address(table[i]->addr); 460 } else { 461 printf("\tPTR\t%#llx\n", table[i]->addr); 462 } 463 } 464 printf("\n"); 465 466 if (base_relative) { 467 output_label("kallsyms_relative_base"); 468 output_address(relative_base); 469 printf("\n"); 470 } 471 472 output_label("kallsyms_num_syms"); 473 printf("\t.long\t%u\n", table_cnt); 474 printf("\n"); 475 476 /* table of offset markers, that give the offset in the compressed stream 477 * every 256 symbols */ 478 markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256)); 479 if (!markers) { 480 fprintf(stderr, "kallsyms failure: " 481 "unable to allocate required memory\n"); 482 exit(EXIT_FAILURE); 483 } 484 485 output_label("kallsyms_names"); 486 off = 0; 487 for (i = 0; i < table_cnt; i++) { 488 if ((i & 0xFF) == 0) 489 markers[i >> 8] = off; 490 491 /* There cannot be any symbol of length zero. */ 492 if (table[i]->len == 0) { 493 fprintf(stderr, "kallsyms failure: " 494 "unexpected zero symbol length\n"); 495 exit(EXIT_FAILURE); 496 } 497 498 /* Only lengths that fit in up-to-two-byte ULEB128 are supported. */ 499 if (table[i]->len > 0x3FFF) { 500 fprintf(stderr, "kallsyms failure: " 501 "unexpected huge symbol length\n"); 502 exit(EXIT_FAILURE); 503 } 504 505 /* Encode length with ULEB128. */ 506 if (table[i]->len <= 0x7F) { 507 /* Most symbols use a single byte for the length. */ 508 printf("\t.byte 0x%02x", table[i]->len); 509 off += table[i]->len + 1; 510 } else { 511 /* "Big" symbols use two bytes. */ 512 printf("\t.byte 0x%02x, 0x%02x", 513 (table[i]->len & 0x7F) | 0x80, 514 (table[i]->len >> 7) & 0x7F); 515 off += table[i]->len + 2; 516 } 517 for (k = 0; k < table[i]->len; k++) 518 printf(", 0x%02x", table[i]->sym[k]); 519 printf("\n"); 520 } 521 printf("\n"); 522 523 output_label("kallsyms_markers"); 524 for (i = 0; i < ((table_cnt + 255) >> 8); i++) 525 printf("\t.long\t%u\n", markers[i]); 526 printf("\n"); 527 528 free(markers); 529 530 output_label("kallsyms_token_table"); 531 off = 0; 532 for (i = 0; i < 256; i++) { 533 best_idx[i] = off; 534 expand_symbol(best_table[i], best_table_len[i], buf); 535 printf("\t.asciz\t\"%s\"\n", buf); 536 off += strlen(buf) + 1; 537 } 538 printf("\n"); 539 540 output_label("kallsyms_token_index"); 541 for (i = 0; i < 256; i++) 542 printf("\t.short\t%d\n", best_idx[i]); 543 printf("\n"); 544 } 545 546 547 /* table lookup compression functions */ 548 549 /* count all the possible tokens in a symbol */ 550 static void learn_symbol(const unsigned char *symbol, int len) 551 { 552 int i; 553 554 for (i = 0; i < len - 1; i++) 555 token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++; 556 } 557 558 /* decrease the count for all the possible tokens in a symbol */ 559 static void forget_symbol(const unsigned char *symbol, int len) 560 { 561 int i; 562 563 for (i = 0; i < len - 1; i++) 564 token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--; 565 } 566 567 /* do the initial token count */ 568 static void build_initial_tok_table(void) 569 { 570 unsigned int i; 571 572 for (i = 0; i < table_cnt; i++) 573 learn_symbol(table[i]->sym, table[i]->len); 574 } 575 576 static unsigned char *find_token(unsigned char *str, int len, 577 const unsigned char *token) 578 { 579 int i; 580 581 for (i = 0; i < len - 1; i++) { 582 if (str[i] == token[0] && str[i+1] == token[1]) 583 return &str[i]; 584 } 585 return NULL; 586 } 587 588 /* replace a given token in all the valid symbols. Use the sampled symbols 589 * to update the counts */ 590 static void compress_symbols(const unsigned char *str, int idx) 591 { 592 unsigned int i, len, size; 593 unsigned char *p1, *p2; 594 595 for (i = 0; i < table_cnt; i++) { 596 597 len = table[i]->len; 598 p1 = table[i]->sym; 599 600 /* find the token on the symbol */ 601 p2 = find_token(p1, len, str); 602 if (!p2) continue; 603 604 /* decrease the counts for this symbol's tokens */ 605 forget_symbol(table[i]->sym, len); 606 607 size = len; 608 609 do { 610 *p2 = idx; 611 p2++; 612 size -= (p2 - p1); 613 memmove(p2, p2 + 1, size); 614 p1 = p2; 615 len--; 616 617 if (size < 2) break; 618 619 /* find the token on the symbol */ 620 p2 = find_token(p1, size, str); 621 622 } while (p2); 623 624 table[i]->len = len; 625 626 /* increase the counts for this symbol's new tokens */ 627 learn_symbol(table[i]->sym, len); 628 } 629 } 630 631 /* search the token with the maximum profit */ 632 static int find_best_token(void) 633 { 634 int i, best, bestprofit; 635 636 bestprofit=-10000; 637 best = 0; 638 639 for (i = 0; i < 0x10000; i++) { 640 if (token_profit[i] > bestprofit) { 641 best = i; 642 bestprofit = token_profit[i]; 643 } 644 } 645 return best; 646 } 647 648 /* this is the core of the algorithm: calculate the "best" table */ 649 static void optimize_result(void) 650 { 651 int i, best; 652 653 /* using the '\0' symbol last allows compress_symbols to use standard 654 * fast string functions */ 655 for (i = 255; i >= 0; i--) { 656 657 /* if this table slot is empty (it is not used by an actual 658 * original char code */ 659 if (!best_table_len[i]) { 660 661 /* find the token with the best profit value */ 662 best = find_best_token(); 663 if (token_profit[best] == 0) 664 break; 665 666 /* place it in the "best" table */ 667 best_table_len[i] = 2; 668 best_table[i][0] = best & 0xFF; 669 best_table[i][1] = (best >> 8) & 0xFF; 670 671 /* replace this token in all the valid symbols */ 672 compress_symbols(best_table[i], i); 673 } 674 } 675 } 676 677 /* start by placing the symbols that are actually used on the table */ 678 static void insert_real_symbols_in_table(void) 679 { 680 unsigned int i, j, c; 681 682 for (i = 0; i < table_cnt; i++) { 683 for (j = 0; j < table[i]->len; j++) { 684 c = table[i]->sym[j]; 685 best_table[c][0]=c; 686 best_table_len[c]=1; 687 } 688 } 689 } 690 691 static void optimize_token_table(void) 692 { 693 build_initial_tok_table(); 694 695 insert_real_symbols_in_table(); 696 697 optimize_result(); 698 } 699 700 /* guess for "linker script provide" symbol */ 701 static int may_be_linker_script_provide_symbol(const struct sym_entry *se) 702 { 703 const char *symbol = sym_name(se); 704 int len = se->len - 1; 705 706 if (len < 8) 707 return 0; 708 709 if (symbol[0] != '_' || symbol[1] != '_') 710 return 0; 711 712 /* __start_XXXXX */ 713 if (!memcmp(symbol + 2, "start_", 6)) 714 return 1; 715 716 /* __stop_XXXXX */ 717 if (!memcmp(symbol + 2, "stop_", 5)) 718 return 1; 719 720 /* __end_XXXXX */ 721 if (!memcmp(symbol + 2, "end_", 4)) 722 return 1; 723 724 /* __XXXXX_start */ 725 if (!memcmp(symbol + len - 6, "_start", 6)) 726 return 1; 727 728 /* __XXXXX_end */ 729 if (!memcmp(symbol + len - 4, "_end", 4)) 730 return 1; 731 732 return 0; 733 } 734 735 static int compare_symbols(const void *a, const void *b) 736 { 737 const struct sym_entry *sa = *(const struct sym_entry **)a; 738 const struct sym_entry *sb = *(const struct sym_entry **)b; 739 int wa, wb; 740 741 /* sort by address first */ 742 if (sa->addr > sb->addr) 743 return 1; 744 if (sa->addr < sb->addr) 745 return -1; 746 747 /* sort by "weakness" type */ 748 wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W'); 749 wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W'); 750 if (wa != wb) 751 return wa - wb; 752 753 /* sort by "linker script provide" type */ 754 wa = may_be_linker_script_provide_symbol(sa); 755 wb = may_be_linker_script_provide_symbol(sb); 756 if (wa != wb) 757 return wa - wb; 758 759 /* sort by the number of prefix underscores */ 760 wa = strspn(sym_name(sa), "_"); 761 wb = strspn(sym_name(sb), "_"); 762 if (wa != wb) 763 return wa - wb; 764 765 /* sort by initial order, so that other symbols are left undisturbed */ 766 return sa->start_pos - sb->start_pos; 767 } 768 769 static void sort_symbols(void) 770 { 771 qsort(table, table_cnt, sizeof(table[0]), compare_symbols); 772 } 773 774 static void make_percpus_absolute(void) 775 { 776 unsigned int i; 777 778 for (i = 0; i < table_cnt; i++) 779 if (symbol_in_range(table[i], &percpu_range, 1)) { 780 /* 781 * Keep the 'A' override for percpu symbols to 782 * ensure consistent behavior compared to older 783 * versions of this tool. 784 */ 785 table[i]->sym[0] = 'A'; 786 table[i]->percpu_absolute = 1; 787 } 788 } 789 790 /* find the minimum non-absolute symbol address */ 791 static void record_relative_base(void) 792 { 793 unsigned int i; 794 795 for (i = 0; i < table_cnt; i++) 796 if (!symbol_absolute(table[i])) { 797 /* 798 * The table is sorted by address. 799 * Take the first non-absolute symbol value. 800 */ 801 relative_base = table[i]->addr; 802 return; 803 } 804 } 805 806 int main(int argc, char **argv) 807 { 808 if (argc >= 2) { 809 int i; 810 for (i = 1; i < argc; i++) { 811 if(strcmp(argv[i], "--all-symbols") == 0) 812 all_symbols = 1; 813 else if (strcmp(argv[i], "--absolute-percpu") == 0) 814 absolute_percpu = 1; 815 else if (strcmp(argv[i], "--base-relative") == 0) 816 base_relative = 1; 817 else 818 usage(); 819 } 820 } else if (argc != 1) 821 usage(); 822 823 read_map(stdin); 824 shrink_table(); 825 if (absolute_percpu) 826 make_percpus_absolute(); 827 sort_symbols(); 828 if (base_relative) 829 record_relative_base(); 830 optimize_token_table(); 831 write_src(); 832 833 return 0; 834 } 835