relocs.c 19 KB

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  1. #include <stdio.h>
  2. #include <stdarg.h>
  3. #include <stdlib.h>
  4. #include <stdint.h>
  5. #include <string.h>
  6. #include <errno.h>
  7. #include <unistd.h>
  8. #include <elf.h>
  9. #include <byteswap.h>
  10. #define USE_BSD
  11. #include <endian.h>
  12. #include <regex.h>
  13. #include <tools/le_byteshift.h>
  14. static void die(char *fmt, ...);
  15. #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  16. static Elf32_Ehdr ehdr;
  17. static unsigned long reloc_count, reloc_idx;
  18. static unsigned long *relocs;
  19. static unsigned long reloc16_count, reloc16_idx;
  20. static unsigned long *relocs16;
  21. struct section {
  22. Elf32_Shdr shdr;
  23. struct section *link;
  24. Elf32_Sym *symtab;
  25. Elf32_Rel *reltab;
  26. char *strtab;
  27. };
  28. static struct section *secs;
  29. enum symtype {
  30. S_ABS,
  31. S_REL,
  32. S_SEG,
  33. S_LIN,
  34. S_NSYMTYPES
  35. };
  36. static const char * const sym_regex_kernel[S_NSYMTYPES] = {
  37. /*
  38. * Following symbols have been audited. There values are constant and do
  39. * not change if bzImage is loaded at a different physical address than
  40. * the address for which it has been compiled. Don't warn user about
  41. * absolute relocations present w.r.t these symbols.
  42. */
  43. [S_ABS] =
  44. "^(xen_irq_disable_direct_reloc$|"
  45. "xen_save_fl_direct_reloc$|"
  46. "VDSO|"
  47. "__crc_)",
  48. /*
  49. * These symbols are known to be relative, even if the linker marks them
  50. * as absolute (typically defined outside any section in the linker script.)
  51. */
  52. [S_REL] =
  53. "^(__init_(begin|end)|"
  54. "__x86_cpu_dev_(start|end)|"
  55. "(__parainstructions|__alt_instructions)(|_end)|"
  56. "(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
  57. "_end)$"
  58. };
  59. static const char * const sym_regex_realmode[S_NSYMTYPES] = {
  60. /*
  61. * These are 16-bit segment symbols when compiling 16-bit code.
  62. */
  63. [S_SEG] =
  64. "^real_mode_seg$",
  65. /*
  66. * These are offsets belonging to segments, as opposed to linear addresses,
  67. * when compiling 16-bit code.
  68. */
  69. [S_LIN] =
  70. "^pa_",
  71. };
  72. static const char * const *sym_regex;
  73. static regex_t sym_regex_c[S_NSYMTYPES];
  74. static int is_reloc(enum symtype type, const char *sym_name)
  75. {
  76. return sym_regex[type] &&
  77. !regexec(&sym_regex_c[type], sym_name, 0, NULL, 0);
  78. }
  79. static void regex_init(int use_real_mode)
  80. {
  81. char errbuf[128];
  82. int err;
  83. int i;
  84. if (use_real_mode)
  85. sym_regex = sym_regex_realmode;
  86. else
  87. sym_regex = sym_regex_kernel;
  88. for (i = 0; i < S_NSYMTYPES; i++) {
  89. if (!sym_regex[i])
  90. continue;
  91. err = regcomp(&sym_regex_c[i], sym_regex[i],
  92. REG_EXTENDED|REG_NOSUB);
  93. if (err) {
  94. regerror(err, &sym_regex_c[i], errbuf, sizeof errbuf);
  95. die("%s", errbuf);
  96. }
  97. }
  98. }
  99. static void die(char *fmt, ...)
  100. {
  101. va_list ap;
  102. va_start(ap, fmt);
  103. vfprintf(stderr, fmt, ap);
  104. va_end(ap);
  105. exit(1);
  106. }
  107. static const char *sym_type(unsigned type)
  108. {
  109. static const char *type_name[] = {
  110. #define SYM_TYPE(X) [X] = #X
  111. SYM_TYPE(STT_NOTYPE),
  112. SYM_TYPE(STT_OBJECT),
  113. SYM_TYPE(STT_FUNC),
  114. SYM_TYPE(STT_SECTION),
  115. SYM_TYPE(STT_FILE),
  116. SYM_TYPE(STT_COMMON),
  117. SYM_TYPE(STT_TLS),
  118. #undef SYM_TYPE
  119. };
  120. const char *name = "unknown sym type name";
  121. if (type < ARRAY_SIZE(type_name)) {
  122. name = type_name[type];
  123. }
  124. return name;
  125. }
  126. static const char *sym_bind(unsigned bind)
  127. {
  128. static const char *bind_name[] = {
  129. #define SYM_BIND(X) [X] = #X
  130. SYM_BIND(STB_LOCAL),
  131. SYM_BIND(STB_GLOBAL),
  132. SYM_BIND(STB_WEAK),
  133. #undef SYM_BIND
  134. };
  135. const char *name = "unknown sym bind name";
  136. if (bind < ARRAY_SIZE(bind_name)) {
  137. name = bind_name[bind];
  138. }
  139. return name;
  140. }
  141. static const char *sym_visibility(unsigned visibility)
  142. {
  143. static const char *visibility_name[] = {
  144. #define SYM_VISIBILITY(X) [X] = #X
  145. SYM_VISIBILITY(STV_DEFAULT),
  146. SYM_VISIBILITY(STV_INTERNAL),
  147. SYM_VISIBILITY(STV_HIDDEN),
  148. SYM_VISIBILITY(STV_PROTECTED),
  149. #undef SYM_VISIBILITY
  150. };
  151. const char *name = "unknown sym visibility name";
  152. if (visibility < ARRAY_SIZE(visibility_name)) {
  153. name = visibility_name[visibility];
  154. }
  155. return name;
  156. }
  157. static const char *rel_type(unsigned type)
  158. {
  159. static const char *type_name[] = {
  160. #define REL_TYPE(X) [X] = #X
  161. REL_TYPE(R_386_NONE),
  162. REL_TYPE(R_386_32),
  163. REL_TYPE(R_386_PC32),
  164. REL_TYPE(R_386_GOT32),
  165. REL_TYPE(R_386_PLT32),
  166. REL_TYPE(R_386_COPY),
  167. REL_TYPE(R_386_GLOB_DAT),
  168. REL_TYPE(R_386_JMP_SLOT),
  169. REL_TYPE(R_386_RELATIVE),
  170. REL_TYPE(R_386_GOTOFF),
  171. REL_TYPE(R_386_GOTPC),
  172. REL_TYPE(R_386_8),
  173. REL_TYPE(R_386_PC8),
  174. REL_TYPE(R_386_16),
  175. REL_TYPE(R_386_PC16),
  176. #undef REL_TYPE
  177. };
  178. const char *name = "unknown type rel type name";
  179. if (type < ARRAY_SIZE(type_name) && type_name[type]) {
  180. name = type_name[type];
  181. }
  182. return name;
  183. }
  184. static const char *sec_name(unsigned shndx)
  185. {
  186. const char *sec_strtab;
  187. const char *name;
  188. sec_strtab = secs[ehdr.e_shstrndx].strtab;
  189. name = "<noname>";
  190. if (shndx < ehdr.e_shnum) {
  191. name = sec_strtab + secs[shndx].shdr.sh_name;
  192. }
  193. else if (shndx == SHN_ABS) {
  194. name = "ABSOLUTE";
  195. }
  196. else if (shndx == SHN_COMMON) {
  197. name = "COMMON";
  198. }
  199. return name;
  200. }
  201. static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
  202. {
  203. const char *name;
  204. name = "<noname>";
  205. if (sym->st_name) {
  206. name = sym_strtab + sym->st_name;
  207. }
  208. else {
  209. name = sec_name(sym->st_shndx);
  210. }
  211. return name;
  212. }
  213. #if BYTE_ORDER == LITTLE_ENDIAN
  214. #define le16_to_cpu(val) (val)
  215. #define le32_to_cpu(val) (val)
  216. #endif
  217. #if BYTE_ORDER == BIG_ENDIAN
  218. #define le16_to_cpu(val) bswap_16(val)
  219. #define le32_to_cpu(val) bswap_32(val)
  220. #endif
  221. static uint16_t elf16_to_cpu(uint16_t val)
  222. {
  223. return le16_to_cpu(val);
  224. }
  225. static uint32_t elf32_to_cpu(uint32_t val)
  226. {
  227. return le32_to_cpu(val);
  228. }
  229. static void read_ehdr(FILE *fp)
  230. {
  231. if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
  232. die("Cannot read ELF header: %s\n",
  233. strerror(errno));
  234. }
  235. if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
  236. die("No ELF magic\n");
  237. }
  238. if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) {
  239. die("Not a 32 bit executable\n");
  240. }
  241. if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
  242. die("Not a LSB ELF executable\n");
  243. }
  244. if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
  245. die("Unknown ELF version\n");
  246. }
  247. /* Convert the fields to native endian */
  248. ehdr.e_type = elf16_to_cpu(ehdr.e_type);
  249. ehdr.e_machine = elf16_to_cpu(ehdr.e_machine);
  250. ehdr.e_version = elf32_to_cpu(ehdr.e_version);
  251. ehdr.e_entry = elf32_to_cpu(ehdr.e_entry);
  252. ehdr.e_phoff = elf32_to_cpu(ehdr.e_phoff);
  253. ehdr.e_shoff = elf32_to_cpu(ehdr.e_shoff);
  254. ehdr.e_flags = elf32_to_cpu(ehdr.e_flags);
  255. ehdr.e_ehsize = elf16_to_cpu(ehdr.e_ehsize);
  256. ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize);
  257. ehdr.e_phnum = elf16_to_cpu(ehdr.e_phnum);
  258. ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize);
  259. ehdr.e_shnum = elf16_to_cpu(ehdr.e_shnum);
  260. ehdr.e_shstrndx = elf16_to_cpu(ehdr.e_shstrndx);
  261. if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
  262. die("Unsupported ELF header type\n");
  263. }
  264. if (ehdr.e_machine != EM_386) {
  265. die("Not for x86\n");
  266. }
  267. if (ehdr.e_version != EV_CURRENT) {
  268. die("Unknown ELF version\n");
  269. }
  270. if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) {
  271. die("Bad Elf header size\n");
  272. }
  273. if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) {
  274. die("Bad program header entry\n");
  275. }
  276. if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) {
  277. die("Bad section header entry\n");
  278. }
  279. if (ehdr.e_shstrndx >= ehdr.e_shnum) {
  280. die("String table index out of bounds\n");
  281. }
  282. }
  283. static void read_shdrs(FILE *fp)
  284. {
  285. int i;
  286. Elf32_Shdr shdr;
  287. secs = calloc(ehdr.e_shnum, sizeof(struct section));
  288. if (!secs) {
  289. die("Unable to allocate %d section headers\n",
  290. ehdr.e_shnum);
  291. }
  292. if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
  293. die("Seek to %d failed: %s\n",
  294. ehdr.e_shoff, strerror(errno));
  295. }
  296. for (i = 0; i < ehdr.e_shnum; i++) {
  297. struct section *sec = &secs[i];
  298. if (fread(&shdr, sizeof shdr, 1, fp) != 1)
  299. die("Cannot read ELF section headers %d/%d: %s\n",
  300. i, ehdr.e_shnum, strerror(errno));
  301. sec->shdr.sh_name = elf32_to_cpu(shdr.sh_name);
  302. sec->shdr.sh_type = elf32_to_cpu(shdr.sh_type);
  303. sec->shdr.sh_flags = elf32_to_cpu(shdr.sh_flags);
  304. sec->shdr.sh_addr = elf32_to_cpu(shdr.sh_addr);
  305. sec->shdr.sh_offset = elf32_to_cpu(shdr.sh_offset);
  306. sec->shdr.sh_size = elf32_to_cpu(shdr.sh_size);
  307. sec->shdr.sh_link = elf32_to_cpu(shdr.sh_link);
  308. sec->shdr.sh_info = elf32_to_cpu(shdr.sh_info);
  309. sec->shdr.sh_addralign = elf32_to_cpu(shdr.sh_addralign);
  310. sec->shdr.sh_entsize = elf32_to_cpu(shdr.sh_entsize);
  311. if (sec->shdr.sh_link < ehdr.e_shnum)
  312. sec->link = &secs[sec->shdr.sh_link];
  313. }
  314. }
  315. static void read_strtabs(FILE *fp)
  316. {
  317. int i;
  318. for (i = 0; i < ehdr.e_shnum; i++) {
  319. struct section *sec = &secs[i];
  320. if (sec->shdr.sh_type != SHT_STRTAB) {
  321. continue;
  322. }
  323. sec->strtab = malloc(sec->shdr.sh_size);
  324. if (!sec->strtab) {
  325. die("malloc of %d bytes for strtab failed\n",
  326. sec->shdr.sh_size);
  327. }
  328. if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
  329. die("Seek to %d failed: %s\n",
  330. sec->shdr.sh_offset, strerror(errno));
  331. }
  332. if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
  333. != sec->shdr.sh_size) {
  334. die("Cannot read symbol table: %s\n",
  335. strerror(errno));
  336. }
  337. }
  338. }
  339. static void read_symtabs(FILE *fp)
  340. {
  341. int i,j;
  342. for (i = 0; i < ehdr.e_shnum; i++) {
  343. struct section *sec = &secs[i];
  344. if (sec->shdr.sh_type != SHT_SYMTAB) {
  345. continue;
  346. }
  347. sec->symtab = malloc(sec->shdr.sh_size);
  348. if (!sec->symtab) {
  349. die("malloc of %d bytes for symtab failed\n",
  350. sec->shdr.sh_size);
  351. }
  352. if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
  353. die("Seek to %d failed: %s\n",
  354. sec->shdr.sh_offset, strerror(errno));
  355. }
  356. if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
  357. != sec->shdr.sh_size) {
  358. die("Cannot read symbol table: %s\n",
  359. strerror(errno));
  360. }
  361. for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
  362. Elf32_Sym *sym = &sec->symtab[j];
  363. sym->st_name = elf32_to_cpu(sym->st_name);
  364. sym->st_value = elf32_to_cpu(sym->st_value);
  365. sym->st_size = elf32_to_cpu(sym->st_size);
  366. sym->st_shndx = elf16_to_cpu(sym->st_shndx);
  367. }
  368. }
  369. }
  370. static void read_relocs(FILE *fp)
  371. {
  372. int i,j;
  373. for (i = 0; i < ehdr.e_shnum; i++) {
  374. struct section *sec = &secs[i];
  375. if (sec->shdr.sh_type != SHT_REL) {
  376. continue;
  377. }
  378. sec->reltab = malloc(sec->shdr.sh_size);
  379. if (!sec->reltab) {
  380. die("malloc of %d bytes for relocs failed\n",
  381. sec->shdr.sh_size);
  382. }
  383. if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
  384. die("Seek to %d failed: %s\n",
  385. sec->shdr.sh_offset, strerror(errno));
  386. }
  387. if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
  388. != sec->shdr.sh_size) {
  389. die("Cannot read symbol table: %s\n",
  390. strerror(errno));
  391. }
  392. for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
  393. Elf32_Rel *rel = &sec->reltab[j];
  394. rel->r_offset = elf32_to_cpu(rel->r_offset);
  395. rel->r_info = elf32_to_cpu(rel->r_info);
  396. }
  397. }
  398. }
  399. static void print_absolute_symbols(void)
  400. {
  401. int i;
  402. printf("Absolute symbols\n");
  403. printf(" Num: Value Size Type Bind Visibility Name\n");
  404. for (i = 0; i < ehdr.e_shnum; i++) {
  405. struct section *sec = &secs[i];
  406. char *sym_strtab;
  407. int j;
  408. if (sec->shdr.sh_type != SHT_SYMTAB) {
  409. continue;
  410. }
  411. sym_strtab = sec->link->strtab;
  412. for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
  413. Elf32_Sym *sym;
  414. const char *name;
  415. sym = &sec->symtab[j];
  416. name = sym_name(sym_strtab, sym);
  417. if (sym->st_shndx != SHN_ABS) {
  418. continue;
  419. }
  420. printf("%5d %08x %5d %10s %10s %12s %s\n",
  421. j, sym->st_value, sym->st_size,
  422. sym_type(ELF32_ST_TYPE(sym->st_info)),
  423. sym_bind(ELF32_ST_BIND(sym->st_info)),
  424. sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)),
  425. name);
  426. }
  427. }
  428. printf("\n");
  429. }
  430. static void print_absolute_relocs(void)
  431. {
  432. int i, printed = 0;
  433. for (i = 0; i < ehdr.e_shnum; i++) {
  434. struct section *sec = &secs[i];
  435. struct section *sec_applies, *sec_symtab;
  436. char *sym_strtab;
  437. Elf32_Sym *sh_symtab;
  438. int j;
  439. if (sec->shdr.sh_type != SHT_REL) {
  440. continue;
  441. }
  442. sec_symtab = sec->link;
  443. sec_applies = &secs[sec->shdr.sh_info];
  444. if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
  445. continue;
  446. }
  447. sh_symtab = sec_symtab->symtab;
  448. sym_strtab = sec_symtab->link->strtab;
  449. for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
  450. Elf32_Rel *rel;
  451. Elf32_Sym *sym;
  452. const char *name;
  453. rel = &sec->reltab[j];
  454. sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
  455. name = sym_name(sym_strtab, sym);
  456. if (sym->st_shndx != SHN_ABS) {
  457. continue;
  458. }
  459. /* Absolute symbols are not relocated if bzImage is
  460. * loaded at a non-compiled address. Display a warning
  461. * to user at compile time about the absolute
  462. * relocations present.
  463. *
  464. * User need to audit the code to make sure
  465. * some symbols which should have been section
  466. * relative have not become absolute because of some
  467. * linker optimization or wrong programming usage.
  468. *
  469. * Before warning check if this absolute symbol
  470. * relocation is harmless.
  471. */
  472. if (is_reloc(S_ABS, name) || is_reloc(S_REL, name))
  473. continue;
  474. if (!printed) {
  475. printf("WARNING: Absolute relocations"
  476. " present\n");
  477. printf("Offset Info Type Sym.Value "
  478. "Sym.Name\n");
  479. printed = 1;
  480. }
  481. printf("%08x %08x %10s %08x %s\n",
  482. rel->r_offset,
  483. rel->r_info,
  484. rel_type(ELF32_R_TYPE(rel->r_info)),
  485. sym->st_value,
  486. name);
  487. }
  488. }
  489. if (printed)
  490. printf("\n");
  491. }
  492. static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym),
  493. int use_real_mode)
  494. {
  495. int i;
  496. /* Walk through the relocations */
  497. for (i = 0; i < ehdr.e_shnum; i++) {
  498. char *sym_strtab;
  499. Elf32_Sym *sh_symtab;
  500. struct section *sec_applies, *sec_symtab;
  501. int j;
  502. struct section *sec = &secs[i];
  503. if (sec->shdr.sh_type != SHT_REL) {
  504. continue;
  505. }
  506. sec_symtab = sec->link;
  507. sec_applies = &secs[sec->shdr.sh_info];
  508. if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
  509. continue;
  510. }
  511. sh_symtab = sec_symtab->symtab;
  512. sym_strtab = sec_symtab->link->strtab;
  513. for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
  514. Elf32_Rel *rel;
  515. Elf32_Sym *sym;
  516. unsigned r_type;
  517. const char *symname;
  518. rel = &sec->reltab[j];
  519. sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
  520. r_type = ELF32_R_TYPE(rel->r_info);
  521. switch (r_type) {
  522. case R_386_NONE:
  523. case R_386_PC32:
  524. case R_386_PC16:
  525. case R_386_PC8:
  526. /*
  527. * NONE can be ignored and and PC relative
  528. * relocations don't need to be adjusted.
  529. */
  530. break;
  531. case R_386_16:
  532. symname = sym_name(sym_strtab, sym);
  533. if (!use_real_mode)
  534. goto bad;
  535. if (sym->st_shndx == SHN_ABS) {
  536. if (is_reloc(S_ABS, symname))
  537. break;
  538. else if (!is_reloc(S_SEG, symname))
  539. goto bad;
  540. } else {
  541. if (is_reloc(S_LIN, symname))
  542. goto bad;
  543. else
  544. break;
  545. }
  546. visit(rel, sym);
  547. break;
  548. case R_386_32:
  549. symname = sym_name(sym_strtab, sym);
  550. if (sym->st_shndx == SHN_ABS) {
  551. if (is_reloc(S_ABS, symname))
  552. break;
  553. else if (!is_reloc(S_REL, symname))
  554. goto bad;
  555. } else {
  556. if (use_real_mode &&
  557. !is_reloc(S_LIN, symname))
  558. break;
  559. }
  560. visit(rel, sym);
  561. break;
  562. default:
  563. die("Unsupported relocation type: %s (%d)\n",
  564. rel_type(r_type), r_type);
  565. break;
  566. bad:
  567. symname = sym_name(sym_strtab, sym);
  568. die("Invalid %s relocation: %s\n",
  569. rel_type(r_type), symname);
  570. }
  571. }
  572. }
  573. }
  574. static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
  575. {
  576. if (ELF32_R_TYPE(rel->r_info) == R_386_16)
  577. reloc16_count++;
  578. else
  579. reloc_count++;
  580. }
  581. static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
  582. {
  583. /* Remember the address that needs to be adjusted. */
  584. if (ELF32_R_TYPE(rel->r_info) == R_386_16)
  585. relocs16[reloc16_idx++] = rel->r_offset;
  586. else
  587. relocs[reloc_idx++] = rel->r_offset;
  588. }
  589. static int cmp_relocs(const void *va, const void *vb)
  590. {
  591. const unsigned long *a, *b;
  592. a = va; b = vb;
  593. return (*a == *b)? 0 : (*a > *b)? 1 : -1;
  594. }
  595. static int write32(unsigned int v, FILE *f)
  596. {
  597. unsigned char buf[4];
  598. put_unaligned_le32(v, buf);
  599. return fwrite(buf, 1, 4, f) == 4 ? 0 : -1;
  600. }
  601. static void emit_relocs(int as_text, int use_real_mode)
  602. {
  603. int i;
  604. /* Count how many relocations I have and allocate space for them. */
  605. reloc_count = 0;
  606. walk_relocs(count_reloc, use_real_mode);
  607. relocs = malloc(reloc_count * sizeof(relocs[0]));
  608. if (!relocs) {
  609. die("malloc of %d entries for relocs failed\n",
  610. reloc_count);
  611. }
  612. relocs16 = malloc(reloc16_count * sizeof(relocs[0]));
  613. if (!relocs16) {
  614. die("malloc of %d entries for relocs16 failed\n",
  615. reloc16_count);
  616. }
  617. /* Collect up the relocations */
  618. reloc_idx = 0;
  619. walk_relocs(collect_reloc, use_real_mode);
  620. if (reloc16_count && !use_real_mode)
  621. die("Segment relocations found but --realmode not specified\n");
  622. /* Order the relocations for more efficient processing */
  623. qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs);
  624. qsort(relocs16, reloc16_count, sizeof(relocs16[0]), cmp_relocs);
  625. /* Print the relocations */
  626. if (as_text) {
  627. /* Print the relocations in a form suitable that
  628. * gas will like.
  629. */
  630. printf(".section \".data.reloc\",\"a\"\n");
  631. printf(".balign 4\n");
  632. if (use_real_mode) {
  633. printf("\t.long %lu\n", reloc16_count);
  634. for (i = 0; i < reloc16_count; i++)
  635. printf("\t.long 0x%08lx\n", relocs16[i]);
  636. printf("\t.long %lu\n", reloc_count);
  637. for (i = 0; i < reloc_count; i++) {
  638. printf("\t.long 0x%08lx\n", relocs[i]);
  639. }
  640. } else {
  641. /* Print a stop */
  642. printf("\t.long 0x%08lx\n", (unsigned long)0);
  643. for (i = 0; i < reloc_count; i++) {
  644. printf("\t.long 0x%08lx\n", relocs[i]);
  645. }
  646. }
  647. printf("\n");
  648. }
  649. else {
  650. if (use_real_mode) {
  651. write32(reloc16_count, stdout);
  652. for (i = 0; i < reloc16_count; i++)
  653. write32(relocs16[i], stdout);
  654. write32(reloc_count, stdout);
  655. /* Now print each relocation */
  656. for (i = 0; i < reloc_count; i++)
  657. write32(relocs[i], stdout);
  658. } else {
  659. /* Print a stop */
  660. write32(0, stdout);
  661. /* Now print each relocation */
  662. for (i = 0; i < reloc_count; i++) {
  663. write32(relocs[i], stdout);
  664. }
  665. }
  666. }
  667. }
  668. static void usage(void)
  669. {
  670. die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n");
  671. }
  672. int main(int argc, char **argv)
  673. {
  674. int show_absolute_syms, show_absolute_relocs;
  675. int as_text, use_real_mode;
  676. const char *fname;
  677. FILE *fp;
  678. int i;
  679. show_absolute_syms = 0;
  680. show_absolute_relocs = 0;
  681. as_text = 0;
  682. use_real_mode = 0;
  683. fname = NULL;
  684. for (i = 1; i < argc; i++) {
  685. char *arg = argv[i];
  686. if (*arg == '-') {
  687. if (strcmp(arg, "--abs-syms") == 0) {
  688. show_absolute_syms = 1;
  689. continue;
  690. }
  691. if (strcmp(arg, "--abs-relocs") == 0) {
  692. show_absolute_relocs = 1;
  693. continue;
  694. }
  695. if (strcmp(arg, "--text") == 0) {
  696. as_text = 1;
  697. continue;
  698. }
  699. if (strcmp(arg, "--realmode") == 0) {
  700. use_real_mode = 1;
  701. continue;
  702. }
  703. }
  704. else if (!fname) {
  705. fname = arg;
  706. continue;
  707. }
  708. usage();
  709. }
  710. if (!fname) {
  711. usage();
  712. }
  713. regex_init(use_real_mode);
  714. fp = fopen(fname, "r");
  715. if (!fp) {
  716. die("Cannot open %s: %s\n",
  717. fname, strerror(errno));
  718. }
  719. read_ehdr(fp);
  720. read_shdrs(fp);
  721. read_strtabs(fp);
  722. read_symtabs(fp);
  723. read_relocs(fp);
  724. if (show_absolute_syms) {
  725. print_absolute_symbols();
  726. return 0;
  727. }
  728. if (show_absolute_relocs) {
  729. print_absolute_relocs();
  730. return 0;
  731. }
  732. emit_relocs(as_text, use_real_mode);
  733. return 0;
  734. }