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TOMOYO Linux Cross Reference
Linux/arch/mips/boot/tools/relocs.c

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  1 /* This is included from relocs_32/64.c */
  2 
  3 #define ElfW(type)              _ElfW(ELF_BITS, type)
  4 #define _ElfW(bits, type)       __ElfW(bits, type)
  5 #define __ElfW(bits, type)      Elf##bits##_##type
  6 
  7 #define Elf_Addr                ElfW(Addr)
  8 #define Elf_Ehdr                ElfW(Ehdr)
  9 #define Elf_Phdr                ElfW(Phdr)
 10 #define Elf_Shdr                ElfW(Shdr)
 11 #define Elf_Sym                 ElfW(Sym)
 12 
 13 static Elf_Ehdr ehdr;
 14 
 15 struct relocs {
 16         uint32_t        *offset;
 17         unsigned long   count;
 18         unsigned long   size;
 19 };
 20 
 21 static struct relocs relocs;
 22 
 23 struct section {
 24         Elf_Shdr       shdr;
 25         struct section *link;
 26         Elf_Sym        *symtab;
 27         Elf_Rel        *reltab;
 28         char           *strtab;
 29         long           shdr_offset;
 30 };
 31 static struct section *secs;
 32 
 33 static const char * const regex_sym_kernel = {
 34 /* Symbols matching these regex's should never be relocated */
 35         "^(__crc_)",
 36 };
 37 
 38 static regex_t sym_regex_c;
 39 
 40 static int regex_skip_reloc(const char *sym_name)
 41 {
 42         return !regexec(&sym_regex_c, sym_name, 0, NULL, 0);
 43 }
 44 
 45 static void regex_init(void)
 46 {
 47         char errbuf[128];
 48         int err;
 49 
 50         err = regcomp(&sym_regex_c, regex_sym_kernel,
 51                         REG_EXTENDED|REG_NOSUB);
 52 
 53         if (err) {
 54                 regerror(err, &sym_regex_c, errbuf, sizeof(errbuf));
 55                 die("%s", errbuf);
 56         }
 57 }
 58 
 59 static const char *rel_type(unsigned type)
 60 {
 61         static const char * const type_name[] = {
 62 #define REL_TYPE(X)[X] = #X
 63                 REL_TYPE(R_MIPS_NONE),
 64                 REL_TYPE(R_MIPS_16),
 65                 REL_TYPE(R_MIPS_32),
 66                 REL_TYPE(R_MIPS_REL32),
 67                 REL_TYPE(R_MIPS_26),
 68                 REL_TYPE(R_MIPS_HI16),
 69                 REL_TYPE(R_MIPS_LO16),
 70                 REL_TYPE(R_MIPS_GPREL16),
 71                 REL_TYPE(R_MIPS_LITERAL),
 72                 REL_TYPE(R_MIPS_GOT16),
 73                 REL_TYPE(R_MIPS_PC16),
 74                 REL_TYPE(R_MIPS_CALL16),
 75                 REL_TYPE(R_MIPS_GPREL32),
 76                 REL_TYPE(R_MIPS_64),
 77                 REL_TYPE(R_MIPS_HIGHER),
 78                 REL_TYPE(R_MIPS_HIGHEST),
 79                 REL_TYPE(R_MIPS_PC21_S2),
 80                 REL_TYPE(R_MIPS_PC26_S2),
 81 #undef REL_TYPE
 82         };
 83         const char *name = "unknown type rel type name";
 84 
 85         if (type < ARRAY_SIZE(type_name) && type_name[type])
 86                 name = type_name[type];
 87         return name;
 88 }
 89 
 90 static const char *sec_name(unsigned shndx)
 91 {
 92         const char *sec_strtab;
 93         const char *name;
 94 
 95         sec_strtab = secs[ehdr.e_shstrndx].strtab;
 96         if (shndx < ehdr.e_shnum)
 97                 name = sec_strtab + secs[shndx].shdr.sh_name;
 98         else if (shndx == SHN_ABS)
 99                 name = "ABSOLUTE";
100         else if (shndx == SHN_COMMON)
101                 name = "COMMON";
102         else
103                 name = "<noname>";
104         return name;
105 }
106 
107 static struct section *sec_lookup(const char *secname)
108 {
109         int i;
110 
111         for (i = 0; i < ehdr.e_shnum; i++)
112                 if (strcmp(secname, sec_name(i)) == 0)
113                         return &secs[i];
114 
115         return NULL;
116 }
117 
118 static const char *sym_name(const char *sym_strtab, Elf_Sym *sym)
119 {
120         const char *name;
121 
122         if (sym->st_name)
123                 name = sym_strtab + sym->st_name;
124         else
125                 name = sec_name(sym->st_shndx);
126         return name;
127 }
128 
129 #if BYTE_ORDER == LITTLE_ENDIAN
130 #define le16_to_cpu(val) (val)
131 #define le32_to_cpu(val) (val)
132 #define le64_to_cpu(val) (val)
133 #define be16_to_cpu(val) bswap_16(val)
134 #define be32_to_cpu(val) bswap_32(val)
135 #define be64_to_cpu(val) bswap_64(val)
136 
137 #define cpu_to_le16(val) (val)
138 #define cpu_to_le32(val) (val)
139 #define cpu_to_le64(val) (val)
140 #define cpu_to_be16(val) bswap_16(val)
141 #define cpu_to_be32(val) bswap_32(val)
142 #define cpu_to_be64(val) bswap_64(val)
143 #endif
144 #if BYTE_ORDER == BIG_ENDIAN
145 #define le16_to_cpu(val) bswap_16(val)
146 #define le32_to_cpu(val) bswap_32(val)
147 #define le64_to_cpu(val) bswap_64(val)
148 #define be16_to_cpu(val) (val)
149 #define be32_to_cpu(val) (val)
150 #define be64_to_cpu(val) (val)
151 
152 #define cpu_to_le16(val) bswap_16(val)
153 #define cpu_to_le32(val) bswap_32(val)
154 #define cpu_to_le64(val) bswap_64(val)
155 #define cpu_to_be16(val) (val)
156 #define cpu_to_be32(val) (val)
157 #define cpu_to_be64(val) (val)
158 #endif
159 
160 static uint16_t elf16_to_cpu(uint16_t val)
161 {
162         if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
163                 return le16_to_cpu(val);
164         else
165                 return be16_to_cpu(val);
166 }
167 
168 static uint32_t elf32_to_cpu(uint32_t val)
169 {
170         if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
171                 return le32_to_cpu(val);
172         else
173                 return be32_to_cpu(val);
174 }
175 
176 static uint32_t cpu_to_elf32(uint32_t val)
177 {
178         if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
179                 return cpu_to_le32(val);
180         else
181                 return cpu_to_be32(val);
182 }
183 
184 #define elf_half_to_cpu(x)      elf16_to_cpu(x)
185 #define elf_word_to_cpu(x)      elf32_to_cpu(x)
186 
187 #if ELF_BITS == 64
188 static uint64_t elf64_to_cpu(uint64_t val)
189 {
190         if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB)
191                 return le64_to_cpu(val);
192         else
193                 return be64_to_cpu(val);
194 }
195 #define elf_addr_to_cpu(x)      elf64_to_cpu(x)
196 #define elf_off_to_cpu(x)       elf64_to_cpu(x)
197 #define elf_xword_to_cpu(x)     elf64_to_cpu(x)
198 #else
199 #define elf_addr_to_cpu(x)      elf32_to_cpu(x)
200 #define elf_off_to_cpu(x)       elf32_to_cpu(x)
201 #define elf_xword_to_cpu(x)     elf32_to_cpu(x)
202 #endif
203 
204 static void read_ehdr(FILE *fp)
205 {
206         if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1)
207                 die("Cannot read ELF header: %s\n", strerror(errno));
208 
209         if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0)
210                 die("No ELF magic\n");
211 
212         if (ehdr.e_ident[EI_CLASS] != ELF_CLASS)
213                 die("Not a %d bit executable\n", ELF_BITS);
214 
215         if ((ehdr.e_ident[EI_DATA] != ELFDATA2LSB) &&
216             (ehdr.e_ident[EI_DATA] != ELFDATA2MSB))
217                 die("Unknown ELF Endianness\n");
218 
219         if (ehdr.e_ident[EI_VERSION] != EV_CURRENT)
220                 die("Unknown ELF version\n");
221 
222         /* Convert the fields to native endian */
223         ehdr.e_type      = elf_half_to_cpu(ehdr.e_type);
224         ehdr.e_machine   = elf_half_to_cpu(ehdr.e_machine);
225         ehdr.e_version   = elf_word_to_cpu(ehdr.e_version);
226         ehdr.e_entry     = elf_addr_to_cpu(ehdr.e_entry);
227         ehdr.e_phoff     = elf_off_to_cpu(ehdr.e_phoff);
228         ehdr.e_shoff     = elf_off_to_cpu(ehdr.e_shoff);
229         ehdr.e_flags     = elf_word_to_cpu(ehdr.e_flags);
230         ehdr.e_ehsize    = elf_half_to_cpu(ehdr.e_ehsize);
231         ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize);
232         ehdr.e_phnum     = elf_half_to_cpu(ehdr.e_phnum);
233         ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize);
234         ehdr.e_shnum     = elf_half_to_cpu(ehdr.e_shnum);
235         ehdr.e_shstrndx  = elf_half_to_cpu(ehdr.e_shstrndx);
236 
237         if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN))
238                 die("Unsupported ELF header type\n");
239 
240         if (ehdr.e_machine != ELF_MACHINE)
241                 die("Not for %s\n", ELF_MACHINE_NAME);
242 
243         if (ehdr.e_version != EV_CURRENT)
244                 die("Unknown ELF version\n");
245 
246         if (ehdr.e_ehsize != sizeof(Elf_Ehdr))
247                 die("Bad Elf header size\n");
248 
249         if (ehdr.e_phentsize != sizeof(Elf_Phdr))
250                 die("Bad program header entry\n");
251 
252         if (ehdr.e_shentsize != sizeof(Elf_Shdr))
253                 die("Bad section header entry\n");
254 
255         if (ehdr.e_shstrndx >= ehdr.e_shnum)
256                 die("String table index out of bounds\n");
257 }
258 
259 static void read_shdrs(FILE *fp)
260 {
261         int i;
262         Elf_Shdr shdr;
263 
264         secs = calloc(ehdr.e_shnum, sizeof(struct section));
265         if (!secs)
266                 die("Unable to allocate %d section headers\n", ehdr.e_shnum);
267 
268         if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0)
269                 die("Seek to %d failed: %s\n", ehdr.e_shoff, strerror(errno));
270 
271         for (i = 0; i < ehdr.e_shnum; i++) {
272                 struct section *sec = &secs[i];
273 
274                 sec->shdr_offset = ftell(fp);
275                 if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
276                         die("Cannot read ELF section headers %d/%d: %s\n",
277                             i, ehdr.e_shnum, strerror(errno));
278                 sec->shdr.sh_name      = elf_word_to_cpu(shdr.sh_name);
279                 sec->shdr.sh_type      = elf_word_to_cpu(shdr.sh_type);
280                 sec->shdr.sh_flags     = elf_xword_to_cpu(shdr.sh_flags);
281                 sec->shdr.sh_addr      = elf_addr_to_cpu(shdr.sh_addr);
282                 sec->shdr.sh_offset    = elf_off_to_cpu(shdr.sh_offset);
283                 sec->shdr.sh_size      = elf_xword_to_cpu(shdr.sh_size);
284                 sec->shdr.sh_link      = elf_word_to_cpu(shdr.sh_link);
285                 sec->shdr.sh_info      = elf_word_to_cpu(shdr.sh_info);
286                 sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign);
287                 sec->shdr.sh_entsize   = elf_xword_to_cpu(shdr.sh_entsize);
288                 if (sec->shdr.sh_link < ehdr.e_shnum)
289                         sec->link = &secs[sec->shdr.sh_link];
290         }
291 }
292 
293 static void read_strtabs(FILE *fp)
294 {
295         int i;
296 
297         for (i = 0; i < ehdr.e_shnum; i++) {
298                 struct section *sec = &secs[i];
299 
300                 if (sec->shdr.sh_type != SHT_STRTAB)
301                         continue;
302 
303                 sec->strtab = malloc(sec->shdr.sh_size);
304                 if (!sec->strtab)
305                         die("malloc of %d bytes for strtab failed\n",
306                             sec->shdr.sh_size);
307 
308                 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
309                         die("Seek to %d failed: %s\n",
310                             sec->shdr.sh_offset, strerror(errno));
311 
312                 if (fread(sec->strtab, 1, sec->shdr.sh_size, fp) !=
313                     sec->shdr.sh_size)
314                         die("Cannot read symbol table: %s\n", strerror(errno));
315         }
316 }
317 
318 static void read_symtabs(FILE *fp)
319 {
320         int i, j;
321 
322         for (i = 0; i < ehdr.e_shnum; i++) {
323                 struct section *sec = &secs[i];
324                 if (sec->shdr.sh_type != SHT_SYMTAB)
325                         continue;
326 
327                 sec->symtab = malloc(sec->shdr.sh_size);
328                 if (!sec->symtab)
329                         die("malloc of %d bytes for symtab failed\n",
330                             sec->shdr.sh_size);
331 
332                 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
333                         die("Seek to %d failed: %s\n",
334                             sec->shdr.sh_offset, strerror(errno));
335 
336                 if (fread(sec->symtab, 1, sec->shdr.sh_size, fp) !=
337                     sec->shdr.sh_size)
338                         die("Cannot read symbol table: %s\n", strerror(errno));
339 
340                 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) {
341                         Elf_Sym *sym = &sec->symtab[j];
342 
343                         sym->st_name  = elf_word_to_cpu(sym->st_name);
344                         sym->st_value = elf_addr_to_cpu(sym->st_value);
345                         sym->st_size  = elf_xword_to_cpu(sym->st_size);
346                         sym->st_shndx = elf_half_to_cpu(sym->st_shndx);
347                 }
348         }
349 }
350 
351 static void read_relocs(FILE *fp)
352 {
353         static unsigned long base = 0;
354         int i, j;
355 
356         if (!base) {
357                 struct section *sec = sec_lookup(".text");
358 
359                 if (!sec)
360                         die("Could not find .text section\n");
361 
362                 base = sec->shdr.sh_addr;
363         }
364 
365         for (i = 0; i < ehdr.e_shnum; i++) {
366                 struct section *sec = &secs[i];
367 
368                 if (sec->shdr.sh_type != SHT_REL_TYPE)
369                         continue;
370 
371                 sec->reltab = malloc(sec->shdr.sh_size);
372                 if (!sec->reltab)
373                         die("malloc of %d bytes for relocs failed\n",
374                             sec->shdr.sh_size);
375 
376                 if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0)
377                         die("Seek to %d failed: %s\n",
378                             sec->shdr.sh_offset, strerror(errno));
379 
380                 if (fread(sec->reltab, 1, sec->shdr.sh_size, fp) !=
381                     sec->shdr.sh_size)
382                         die("Cannot read symbol table: %s\n", strerror(errno));
383 
384                 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
385                         Elf_Rel *rel = &sec->reltab[j];
386 
387                         rel->r_offset = elf_addr_to_cpu(rel->r_offset);
388                         /* Set offset into kernel image */
389                         rel->r_offset -= base;
390 #if (ELF_BITS == 32)
391                         rel->r_info   = elf_xword_to_cpu(rel->r_info);
392 #else
393                         /* Convert MIPS64 RELA format - only the symbol
394                          * index needs converting to native endianness
395                          */
396                         rel->r_info   = rel->r_info;
397                         ELF_R_SYM(rel->r_info) = elf32_to_cpu(ELF_R_SYM(rel->r_info));
398 #endif
399 #if (SHT_REL_TYPE == SHT_RELA)
400                         rel->r_addend = elf_xword_to_cpu(rel->r_addend);
401 #endif
402                 }
403         }
404 }
405 
406 static void remove_relocs(FILE *fp)
407 {
408         int i;
409         Elf_Shdr shdr;
410 
411         for (i = 0; i < ehdr.e_shnum; i++) {
412                 struct section *sec = &secs[i];
413 
414                 if (sec->shdr.sh_type != SHT_REL_TYPE)
415                         continue;
416 
417                 if (fseek(fp, sec->shdr_offset, SEEK_SET) < 0)
418                         die("Seek to %d failed: %s\n",
419                             sec->shdr_offset, strerror(errno));
420 
421                 if (fread(&shdr, sizeof(shdr), 1, fp) != 1)
422                         die("Cannot read ELF section headers %d/%d: %s\n",
423                             i, ehdr.e_shnum, strerror(errno));
424 
425                 /* Set relocation section size to 0, effectively removing it.
426                  * This is necessary due to lack of support for relocations
427                  * in objcopy when creating 32bit elf from 64bit elf.
428                  */
429                 shdr.sh_size = 0;
430 
431                 if (fseek(fp, sec->shdr_offset, SEEK_SET) < 0)
432                         die("Seek to %d failed: %s\n",
433                             sec->shdr_offset, strerror(errno));
434 
435                 if (fwrite(&shdr, sizeof(shdr), 1, fp) != 1)
436                         die("Cannot write ELF section headers %d/%d: %s\n",
437                             i, ehdr.e_shnum, strerror(errno));
438         }
439 }
440 
441 static void add_reloc(struct relocs *r, uint32_t offset, unsigned type)
442 {
443         /* Relocation representation in binary table:
444          * |76543210|76543210|76543210|76543210|
445          * |  Type  |  offset from _text >> 2  |
446          */
447         offset >>= 2;
448         if (offset > 0x00FFFFFF)
449                 die("Kernel image exceeds maximum size for relocation!\n");
450 
451         offset = (offset & 0x00FFFFFF) | ((type & 0xFF) << 24);
452 
453         if (r->count == r->size) {
454                 unsigned long newsize = r->size + 50000;
455                 void *mem = realloc(r->offset, newsize * sizeof(r->offset[0]));
456 
457                 if (!mem)
458                         die("realloc failed\n");
459 
460                 r->offset = mem;
461                 r->size = newsize;
462         }
463         r->offset[r->count++] = offset;
464 }
465 
466 static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel,
467                         Elf_Sym *sym, const char *symname))
468 {
469         int i;
470 
471         /* Walk through the relocations */
472         for (i = 0; i < ehdr.e_shnum; i++) {
473                 char *sym_strtab;
474                 Elf_Sym *sh_symtab;
475                 struct section *sec_applies, *sec_symtab;
476                 int j;
477                 struct section *sec = &secs[i];
478 
479                 if (sec->shdr.sh_type != SHT_REL_TYPE)
480                         continue;
481 
482                 sec_symtab  = sec->link;
483                 sec_applies = &secs[sec->shdr.sh_info];
484                 if (!(sec_applies->shdr.sh_flags & SHF_ALLOC))
485                         continue;
486 
487                 sh_symtab = sec_symtab->symtab;
488                 sym_strtab = sec_symtab->link->strtab;
489                 for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) {
490                         Elf_Rel *rel = &sec->reltab[j];
491                         Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
492                         const char *symname = sym_name(sym_strtab, sym);
493 
494                         process(sec, rel, sym, symname);
495                 }
496         }
497 }
498 
499 static int do_reloc(struct section *sec, Elf_Rel *rel, Elf_Sym *sym,
500                       const char *symname)
501 {
502         unsigned r_type = ELF_R_TYPE(rel->r_info);
503         unsigned bind = ELF_ST_BIND(sym->st_info);
504 
505         if ((bind == STB_WEAK) && (sym->st_value == 0)) {
506                 /* Don't relocate weak symbols without a target */
507                 return 0;
508         }
509 
510         if (regex_skip_reloc(symname))
511                 return 0;
512 
513         switch (r_type) {
514         case R_MIPS_NONE:
515         case R_MIPS_REL32:
516         case R_MIPS_PC16:
517         case R_MIPS_PC21_S2:
518         case R_MIPS_PC26_S2:
519                 /*
520                  * NONE can be ignored and PC relative relocations don't
521                  * need to be adjusted.
522                  */
523         case R_MIPS_HIGHEST:
524         case R_MIPS_HIGHER:
525                 /* We support relocating within the same 4Gb segment only,
526                  * thus leaving the top 32bits unchanged
527                  */
528         case R_MIPS_LO16:
529                 /* We support relocating by 64k jumps only
530                  * thus leaving the bottom 16bits unchanged
531                  */
532                 break;
533 
534         case R_MIPS_64:
535         case R_MIPS_32:
536         case R_MIPS_26:
537         case R_MIPS_HI16:
538                 add_reloc(&relocs, rel->r_offset, r_type);
539                 break;
540 
541         default:
542                 die("Unsupported relocation type: %s (%d)\n",
543                     rel_type(r_type), r_type);
544                 break;
545         }
546 
547         return 0;
548 }
549 
550 static int write_reloc_as_bin(uint32_t v, FILE *f)
551 {
552         unsigned char buf[4];
553 
554         v = cpu_to_elf32(v);
555 
556         memcpy(buf, &v, sizeof(uint32_t));
557         return fwrite(buf, 1, 4, f);
558 }
559 
560 static int write_reloc_as_text(uint32_t v, FILE *f)
561 {
562         int res;
563 
564         res = fprintf(f, "\t.long 0x%08"PRIx32"\n", v);
565         if (res < 0)
566                 return res;
567         else
568                 return sizeof(uint32_t);
569 }
570 
571 static void emit_relocs(int as_text, int as_bin, FILE *outf)
572 {
573         int i;
574         int (*write_reloc)(uint32_t, FILE *) = write_reloc_as_bin;
575         int size = 0;
576         int size_reserved;
577         struct section *sec_reloc;
578 
579         sec_reloc = sec_lookup(".data.reloc");
580         if (!sec_reloc)
581                 die("Could not find relocation section\n");
582 
583         size_reserved = sec_reloc->shdr.sh_size;
584 
585         /* Collect up the relocations */
586         walk_relocs(do_reloc);
587 
588         /* Print the relocations */
589         if (as_text) {
590                 /* Print the relocations in a form suitable that
591                  * gas will like.
592                  */
593                 printf(".section \".data.reloc\",\"a\"\n");
594                 printf(".balign 4\n");
595                 /* Output text to stdout */
596                 write_reloc = write_reloc_as_text;
597                 outf = stdout;
598         } else if (as_bin) {
599                 /* Output raw binary to stdout */
600                 outf = stdout;
601         } else {
602                 /* Seek to offset of the relocation section.
603                 * Each relocation is then written into the
604                 * vmlinux kernel image.
605                 */
606                 if (fseek(outf, sec_reloc->shdr.sh_offset, SEEK_SET) < 0) {
607                         die("Seek to %d failed: %s\n",
608                                 sec_reloc->shdr.sh_offset, strerror(errno));
609                 }
610         }
611 
612         for (i = 0; i < relocs.count; i++)
613                 size += write_reloc(relocs.offset[i], outf);
614 
615         /* Print a stop, but only if we've actually written some relocs */
616         if (size)
617                 size += write_reloc(0, outf);
618 
619         if (size > size_reserved)
620                 /* Die, but suggest a value for CONFIG_RELOCATION_TABLE_SIZE
621                  * which will fix this problem and allow a bit of headroom
622                  * if more kernel features are enabled
623                  */
624                 die("Relocations overflow available space!\n" \
625                     "Please adjust CONFIG_RELOCATION_TABLE_SIZE " \
626                     "to at least 0x%08x\n", (size + 0x1000) & ~0xFFF);
627 }
628 
629 /*
630  * As an aid to debugging problems with different linkers
631  * print summary information about the relocs.
632  * Since different linkers tend to emit the sections in
633  * different orders we use the section names in the output.
634  */
635 static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
636                                 const char *symname)
637 {
638         printf("%16s  0x%08x  %16s  %40s  %16s\n",
639                 sec_name(sec->shdr.sh_info),
640                 (unsigned int)rel->r_offset,
641                 rel_type(ELF_R_TYPE(rel->r_info)),
642                 symname,
643                 sec_name(sym->st_shndx));
644         return 0;
645 }
646 
647 static void print_reloc_info(void)
648 {
649         printf("%16s  %10s  %16s  %40s  %16s\n",
650                 "reloc section",
651                 "offset",
652                 "reloc type",
653                 "symbol",
654                 "symbol section");
655         walk_relocs(do_reloc_info);
656 }
657 
658 #if ELF_BITS == 64
659 # define process process_64
660 #else
661 # define process process_32
662 #endif
663 
664 void process(FILE *fp, int as_text, int as_bin,
665              int show_reloc_info, int keep_relocs)
666 {
667         regex_init();
668         read_ehdr(fp);
669         read_shdrs(fp);
670         read_strtabs(fp);
671         read_symtabs(fp);
672         read_relocs(fp);
673         if (show_reloc_info) {
674                 print_reloc_info();
675                 return;
676         }
677         emit_relocs(as_text, as_bin, fp);
678         if (!keep_relocs)
679                 remove_relocs(fp);
680 }
681 

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