Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
766c5803 MR |
2 | /* This is included from relocs_32/64.c */ |
3 | ||
4 | #define ElfW(type) _ElfW(ELF_BITS, type) | |
5 | #define _ElfW(bits, type) __ElfW(bits, type) | |
6 | #define __ElfW(bits, type) Elf##bits##_##type | |
7 | ||
8 | #define Elf_Addr ElfW(Addr) | |
9 | #define Elf_Ehdr ElfW(Ehdr) | |
10 | #define Elf_Phdr ElfW(Phdr) | |
11 | #define Elf_Shdr ElfW(Shdr) | |
12 | #define Elf_Sym ElfW(Sym) | |
13 | ||
14 | static Elf_Ehdr ehdr; | |
15 | ||
16 | struct relocs { | |
17 | uint32_t *offset; | |
18 | unsigned long count; | |
19 | unsigned long size; | |
20 | }; | |
21 | ||
22 | static struct relocs relocs; | |
23 | ||
24 | struct section { | |
25 | Elf_Shdr shdr; | |
26 | struct section *link; | |
27 | Elf_Sym *symtab; | |
28 | Elf_Rel *reltab; | |
29 | char *strtab; | |
30 | long shdr_offset; | |
31 | }; | |
32 | static struct section *secs; | |
33 | ||
34 | static const char * const regex_sym_kernel = { | |
35 | /* Symbols matching these regex's should never be relocated */ | |
36 | "^(__crc_)", | |
37 | }; | |
38 | ||
39 | static regex_t sym_regex_c; | |
40 | ||
41 | static int regex_skip_reloc(const char *sym_name) | |
42 | { | |
43 | return !regexec(&sym_regex_c, sym_name, 0, NULL, 0); | |
44 | } | |
45 | ||
46 | static void regex_init(void) | |
47 | { | |
48 | char errbuf[128]; | |
49 | int err; | |
50 | ||
51 | err = regcomp(&sym_regex_c, regex_sym_kernel, | |
52 | REG_EXTENDED|REG_NOSUB); | |
53 | ||
54 | if (err) { | |
55 | regerror(err, &sym_regex_c, errbuf, sizeof(errbuf)); | |
56 | die("%s", errbuf); | |
57 | } | |
58 | } | |
59 | ||
60 | static const char *rel_type(unsigned type) | |
61 | { | |
62 | static const char * const type_name[] = { | |
63 | #define REL_TYPE(X)[X] = #X | |
64 | REL_TYPE(R_MIPS_NONE), | |
65 | REL_TYPE(R_MIPS_16), | |
66 | REL_TYPE(R_MIPS_32), | |
67 | REL_TYPE(R_MIPS_REL32), | |
68 | REL_TYPE(R_MIPS_26), | |
69 | REL_TYPE(R_MIPS_HI16), | |
70 | REL_TYPE(R_MIPS_LO16), | |
71 | REL_TYPE(R_MIPS_GPREL16), | |
72 | REL_TYPE(R_MIPS_LITERAL), | |
73 | REL_TYPE(R_MIPS_GOT16), | |
74 | REL_TYPE(R_MIPS_PC16), | |
75 | REL_TYPE(R_MIPS_CALL16), | |
76 | REL_TYPE(R_MIPS_GPREL32), | |
77 | REL_TYPE(R_MIPS_64), | |
78 | REL_TYPE(R_MIPS_HIGHER), | |
79 | REL_TYPE(R_MIPS_HIGHEST), | |
80 | REL_TYPE(R_MIPS_PC21_S2), | |
81 | REL_TYPE(R_MIPS_PC26_S2), | |
82 | #undef REL_TYPE | |
83 | }; | |
84 | const char *name = "unknown type rel type name"; | |
85 | ||
86 | if (type < ARRAY_SIZE(type_name) && type_name[type]) | |
87 | name = type_name[type]; | |
88 | return name; | |
89 | } | |
90 | ||
91 | static const char *sec_name(unsigned shndx) | |
92 | { | |
93 | const char *sec_strtab; | |
94 | const char *name; | |
95 | ||
96 | sec_strtab = secs[ehdr.e_shstrndx].strtab; | |
97 | if (shndx < ehdr.e_shnum) | |
98 | name = sec_strtab + secs[shndx].shdr.sh_name; | |
99 | else if (shndx == SHN_ABS) | |
100 | name = "ABSOLUTE"; | |
101 | else if (shndx == SHN_COMMON) | |
102 | name = "COMMON"; | |
103 | else | |
104 | name = "<noname>"; | |
105 | return name; | |
106 | } | |
107 | ||
108 | static struct section *sec_lookup(const char *secname) | |
109 | { | |
110 | int i; | |
111 | ||
112 | for (i = 0; i < ehdr.e_shnum; i++) | |
113 | if (strcmp(secname, sec_name(i)) == 0) | |
114 | return &secs[i]; | |
115 | ||
116 | return NULL; | |
117 | } | |
118 | ||
119 | static const char *sym_name(const char *sym_strtab, Elf_Sym *sym) | |
120 | { | |
121 | const char *name; | |
122 | ||
123 | if (sym->st_name) | |
124 | name = sym_strtab + sym->st_name; | |
125 | else | |
126 | name = sec_name(sym->st_shndx); | |
127 | return name; | |
128 | } | |
129 | ||
130 | #if BYTE_ORDER == LITTLE_ENDIAN | |
131 | #define le16_to_cpu(val) (val) | |
132 | #define le32_to_cpu(val) (val) | |
133 | #define le64_to_cpu(val) (val) | |
134 | #define be16_to_cpu(val) bswap_16(val) | |
135 | #define be32_to_cpu(val) bswap_32(val) | |
136 | #define be64_to_cpu(val) bswap_64(val) | |
137 | ||
138 | #define cpu_to_le16(val) (val) | |
139 | #define cpu_to_le32(val) (val) | |
140 | #define cpu_to_le64(val) (val) | |
141 | #define cpu_to_be16(val) bswap_16(val) | |
142 | #define cpu_to_be32(val) bswap_32(val) | |
143 | #define cpu_to_be64(val) bswap_64(val) | |
144 | #endif | |
145 | #if BYTE_ORDER == BIG_ENDIAN | |
146 | #define le16_to_cpu(val) bswap_16(val) | |
147 | #define le32_to_cpu(val) bswap_32(val) | |
148 | #define le64_to_cpu(val) bswap_64(val) | |
149 | #define be16_to_cpu(val) (val) | |
150 | #define be32_to_cpu(val) (val) | |
151 | #define be64_to_cpu(val) (val) | |
152 | ||
153 | #define cpu_to_le16(val) bswap_16(val) | |
154 | #define cpu_to_le32(val) bswap_32(val) | |
155 | #define cpu_to_le64(val) bswap_64(val) | |
156 | #define cpu_to_be16(val) (val) | |
157 | #define cpu_to_be32(val) (val) | |
158 | #define cpu_to_be64(val) (val) | |
159 | #endif | |
160 | ||
161 | static uint16_t elf16_to_cpu(uint16_t val) | |
162 | { | |
163 | if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) | |
164 | return le16_to_cpu(val); | |
165 | else | |
166 | return be16_to_cpu(val); | |
167 | } | |
168 | ||
169 | static uint32_t elf32_to_cpu(uint32_t val) | |
170 | { | |
171 | if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) | |
172 | return le32_to_cpu(val); | |
173 | else | |
174 | return be32_to_cpu(val); | |
175 | } | |
176 | ||
177 | static uint32_t cpu_to_elf32(uint32_t val) | |
178 | { | |
179 | if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) | |
180 | return cpu_to_le32(val); | |
181 | else | |
182 | return cpu_to_be32(val); | |
183 | } | |
184 | ||
185 | #define elf_half_to_cpu(x) elf16_to_cpu(x) | |
186 | #define elf_word_to_cpu(x) elf32_to_cpu(x) | |
187 | ||
188 | #if ELF_BITS == 64 | |
189 | static uint64_t elf64_to_cpu(uint64_t val) | |
190 | { | |
191 | if (ehdr.e_ident[EI_DATA] == ELFDATA2LSB) | |
192 | return le64_to_cpu(val); | |
193 | else | |
194 | return be64_to_cpu(val); | |
195 | } | |
196 | #define elf_addr_to_cpu(x) elf64_to_cpu(x) | |
197 | #define elf_off_to_cpu(x) elf64_to_cpu(x) | |
198 | #define elf_xword_to_cpu(x) elf64_to_cpu(x) | |
199 | #else | |
200 | #define elf_addr_to_cpu(x) elf32_to_cpu(x) | |
201 | #define elf_off_to_cpu(x) elf32_to_cpu(x) | |
202 | #define elf_xword_to_cpu(x) elf32_to_cpu(x) | |
203 | #endif | |
204 | ||
205 | static void read_ehdr(FILE *fp) | |
206 | { | |
207 | if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) | |
208 | die("Cannot read ELF header: %s\n", strerror(errno)); | |
209 | ||
210 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) | |
211 | die("No ELF magic\n"); | |
212 | ||
213 | if (ehdr.e_ident[EI_CLASS] != ELF_CLASS) | |
214 | die("Not a %d bit executable\n", ELF_BITS); | |
215 | ||
216 | if ((ehdr.e_ident[EI_DATA] != ELFDATA2LSB) && | |
217 | (ehdr.e_ident[EI_DATA] != ELFDATA2MSB)) | |
218 | die("Unknown ELF Endianness\n"); | |
219 | ||
220 | if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) | |
221 | die("Unknown ELF version\n"); | |
222 | ||
223 | /* Convert the fields to native endian */ | |
224 | ehdr.e_type = elf_half_to_cpu(ehdr.e_type); | |
225 | ehdr.e_machine = elf_half_to_cpu(ehdr.e_machine); | |
226 | ehdr.e_version = elf_word_to_cpu(ehdr.e_version); | |
227 | ehdr.e_entry = elf_addr_to_cpu(ehdr.e_entry); | |
228 | ehdr.e_phoff = elf_off_to_cpu(ehdr.e_phoff); | |
229 | ehdr.e_shoff = elf_off_to_cpu(ehdr.e_shoff); | |
230 | ehdr.e_flags = elf_word_to_cpu(ehdr.e_flags); | |
231 | ehdr.e_ehsize = elf_half_to_cpu(ehdr.e_ehsize); | |
232 | ehdr.e_phentsize = elf_half_to_cpu(ehdr.e_phentsize); | |
233 | ehdr.e_phnum = elf_half_to_cpu(ehdr.e_phnum); | |
234 | ehdr.e_shentsize = elf_half_to_cpu(ehdr.e_shentsize); | |
235 | ehdr.e_shnum = elf_half_to_cpu(ehdr.e_shnum); | |
236 | ehdr.e_shstrndx = elf_half_to_cpu(ehdr.e_shstrndx); | |
237 | ||
238 | if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) | |
239 | die("Unsupported ELF header type\n"); | |
240 | ||
241 | if (ehdr.e_machine != ELF_MACHINE) | |
242 | die("Not for %s\n", ELF_MACHINE_NAME); | |
243 | ||
244 | if (ehdr.e_version != EV_CURRENT) | |
245 | die("Unknown ELF version\n"); | |
246 | ||
247 | if (ehdr.e_ehsize != sizeof(Elf_Ehdr)) | |
70e79866 | 248 | die("Bad ELF header size\n"); |
766c5803 MR |
249 | |
250 | if (ehdr.e_phentsize != sizeof(Elf_Phdr)) | |
251 | die("Bad program header entry\n"); | |
252 | ||
253 | if (ehdr.e_shentsize != sizeof(Elf_Shdr)) | |
254 | die("Bad section header entry\n"); | |
255 | ||
256 | if (ehdr.e_shstrndx >= ehdr.e_shnum) | |
257 | die("String table index out of bounds\n"); | |
258 | } | |
259 | ||
260 | static void read_shdrs(FILE *fp) | |
261 | { | |
262 | int i; | |
263 | Elf_Shdr shdr; | |
264 | ||
265 | secs = calloc(ehdr.e_shnum, sizeof(struct section)); | |
266 | if (!secs) | |
267 | die("Unable to allocate %d section headers\n", ehdr.e_shnum); | |
268 | ||
269 | if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) | |
270 | die("Seek to %d failed: %s\n", ehdr.e_shoff, strerror(errno)); | |
271 | ||
272 | for (i = 0; i < ehdr.e_shnum; i++) { | |
273 | struct section *sec = &secs[i]; | |
274 | ||
275 | sec->shdr_offset = ftell(fp); | |
276 | if (fread(&shdr, sizeof(shdr), 1, fp) != 1) | |
277 | die("Cannot read ELF section headers %d/%d: %s\n", | |
278 | i, ehdr.e_shnum, strerror(errno)); | |
279 | sec->shdr.sh_name = elf_word_to_cpu(shdr.sh_name); | |
280 | sec->shdr.sh_type = elf_word_to_cpu(shdr.sh_type); | |
281 | sec->shdr.sh_flags = elf_xword_to_cpu(shdr.sh_flags); | |
282 | sec->shdr.sh_addr = elf_addr_to_cpu(shdr.sh_addr); | |
283 | sec->shdr.sh_offset = elf_off_to_cpu(shdr.sh_offset); | |
284 | sec->shdr.sh_size = elf_xword_to_cpu(shdr.sh_size); | |
285 | sec->shdr.sh_link = elf_word_to_cpu(shdr.sh_link); | |
286 | sec->shdr.sh_info = elf_word_to_cpu(shdr.sh_info); | |
287 | sec->shdr.sh_addralign = elf_xword_to_cpu(shdr.sh_addralign); | |
288 | sec->shdr.sh_entsize = elf_xword_to_cpu(shdr.sh_entsize); | |
289 | if (sec->shdr.sh_link < ehdr.e_shnum) | |
290 | sec->link = &secs[sec->shdr.sh_link]; | |
291 | } | |
292 | } | |
293 | ||
294 | static void read_strtabs(FILE *fp) | |
295 | { | |
296 | int i; | |
297 | ||
298 | for (i = 0; i < ehdr.e_shnum; i++) { | |
299 | struct section *sec = &secs[i]; | |
300 | ||
301 | if (sec->shdr.sh_type != SHT_STRTAB) | |
302 | continue; | |
303 | ||
304 | sec->strtab = malloc(sec->shdr.sh_size); | |
305 | if (!sec->strtab) | |
306 | die("malloc of %d bytes for strtab failed\n", | |
307 | sec->shdr.sh_size); | |
308 | ||
309 | if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) | |
310 | die("Seek to %d failed: %s\n", | |
311 | sec->shdr.sh_offset, strerror(errno)); | |
312 | ||
313 | if (fread(sec->strtab, 1, sec->shdr.sh_size, fp) != | |
314 | sec->shdr.sh_size) | |
315 | die("Cannot read symbol table: %s\n", strerror(errno)); | |
316 | } | |
317 | } | |
318 | ||
319 | static void read_symtabs(FILE *fp) | |
320 | { | |
321 | int i, j; | |
322 | ||
323 | for (i = 0; i < ehdr.e_shnum; i++) { | |
324 | struct section *sec = &secs[i]; | |
325 | if (sec->shdr.sh_type != SHT_SYMTAB) | |
326 | continue; | |
327 | ||
328 | sec->symtab = malloc(sec->shdr.sh_size); | |
329 | if (!sec->symtab) | |
330 | die("malloc of %d bytes for symtab failed\n", | |
331 | sec->shdr.sh_size); | |
332 | ||
333 | if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) | |
334 | die("Seek to %d failed: %s\n", | |
335 | sec->shdr.sh_offset, strerror(errno)); | |
336 | ||
337 | if (fread(sec->symtab, 1, sec->shdr.sh_size, fp) != | |
338 | sec->shdr.sh_size) | |
339 | die("Cannot read symbol table: %s\n", strerror(errno)); | |
340 | ||
341 | for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Sym); j++) { | |
342 | Elf_Sym *sym = &sec->symtab[j]; | |
343 | ||
344 | sym->st_name = elf_word_to_cpu(sym->st_name); | |
345 | sym->st_value = elf_addr_to_cpu(sym->st_value); | |
346 | sym->st_size = elf_xword_to_cpu(sym->st_size); | |
347 | sym->st_shndx = elf_half_to_cpu(sym->st_shndx); | |
348 | } | |
349 | } | |
350 | } | |
351 | ||
352 | static void read_relocs(FILE *fp) | |
353 | { | |
a4fa106e | 354 | static unsigned long base; |
766c5803 MR |
355 | int i, j; |
356 | ||
357 | if (!base) { | |
358 | struct section *sec = sec_lookup(".text"); | |
359 | ||
360 | if (!sec) | |
361 | die("Could not find .text section\n"); | |
362 | ||
363 | base = sec->shdr.sh_addr; | |
364 | } | |
365 | ||
366 | for (i = 0; i < ehdr.e_shnum; i++) { | |
367 | struct section *sec = &secs[i]; | |
368 | ||
369 | if (sec->shdr.sh_type != SHT_REL_TYPE) | |
370 | continue; | |
371 | ||
372 | sec->reltab = malloc(sec->shdr.sh_size); | |
373 | if (!sec->reltab) | |
374 | die("malloc of %d bytes for relocs failed\n", | |
375 | sec->shdr.sh_size); | |
376 | ||
377 | if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) | |
378 | die("Seek to %d failed: %s\n", | |
379 | sec->shdr.sh_offset, strerror(errno)); | |
380 | ||
381 | if (fread(sec->reltab, 1, sec->shdr.sh_size, fp) != | |
382 | sec->shdr.sh_size) | |
383 | die("Cannot read symbol table: %s\n", strerror(errno)); | |
384 | ||
385 | for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) { | |
386 | Elf_Rel *rel = &sec->reltab[j]; | |
387 | ||
388 | rel->r_offset = elf_addr_to_cpu(rel->r_offset); | |
389 | /* Set offset into kernel image */ | |
390 | rel->r_offset -= base; | |
391 | #if (ELF_BITS == 32) | |
392 | rel->r_info = elf_xword_to_cpu(rel->r_info); | |
393 | #else | |
394 | /* Convert MIPS64 RELA format - only the symbol | |
395 | * index needs converting to native endianness | |
396 | */ | |
397 | rel->r_info = rel->r_info; | |
398 | ELF_R_SYM(rel->r_info) = elf32_to_cpu(ELF_R_SYM(rel->r_info)); | |
399 | #endif | |
400 | #if (SHT_REL_TYPE == SHT_RELA) | |
401 | rel->r_addend = elf_xword_to_cpu(rel->r_addend); | |
402 | #endif | |
403 | } | |
404 | } | |
405 | } | |
406 | ||
407 | static void remove_relocs(FILE *fp) | |
408 | { | |
409 | int i; | |
410 | Elf_Shdr shdr; | |
411 | ||
412 | for (i = 0; i < ehdr.e_shnum; i++) { | |
413 | struct section *sec = &secs[i]; | |
414 | ||
415 | if (sec->shdr.sh_type != SHT_REL_TYPE) | |
416 | continue; | |
417 | ||
418 | if (fseek(fp, sec->shdr_offset, SEEK_SET) < 0) | |
419 | die("Seek to %d failed: %s\n", | |
420 | sec->shdr_offset, strerror(errno)); | |
421 | ||
422 | if (fread(&shdr, sizeof(shdr), 1, fp) != 1) | |
423 | die("Cannot read ELF section headers %d/%d: %s\n", | |
424 | i, ehdr.e_shnum, strerror(errno)); | |
425 | ||
426 | /* Set relocation section size to 0, effectively removing it. | |
427 | * This is necessary due to lack of support for relocations | |
428 | * in objcopy when creating 32bit elf from 64bit elf. | |
429 | */ | |
430 | shdr.sh_size = 0; | |
431 | ||
432 | if (fseek(fp, sec->shdr_offset, SEEK_SET) < 0) | |
433 | die("Seek to %d failed: %s\n", | |
434 | sec->shdr_offset, strerror(errno)); | |
435 | ||
436 | if (fwrite(&shdr, sizeof(shdr), 1, fp) != 1) | |
437 | die("Cannot write ELF section headers %d/%d: %s\n", | |
438 | i, ehdr.e_shnum, strerror(errno)); | |
439 | } | |
440 | } | |
441 | ||
442 | static void add_reloc(struct relocs *r, uint32_t offset, unsigned type) | |
443 | { | |
444 | /* Relocation representation in binary table: | |
445 | * |76543210|76543210|76543210|76543210| | |
446 | * | Type | offset from _text >> 2 | | |
447 | */ | |
448 | offset >>= 2; | |
449 | if (offset > 0x00FFFFFF) | |
450 | die("Kernel image exceeds maximum size for relocation!\n"); | |
451 | ||
452 | offset = (offset & 0x00FFFFFF) | ((type & 0xFF) << 24); | |
453 | ||
454 | if (r->count == r->size) { | |
455 | unsigned long newsize = r->size + 50000; | |
456 | void *mem = realloc(r->offset, newsize * sizeof(r->offset[0])); | |
457 | ||
458 | if (!mem) | |
459 | die("realloc failed\n"); | |
460 | ||
461 | r->offset = mem; | |
462 | r->size = newsize; | |
463 | } | |
464 | r->offset[r->count++] = offset; | |
465 | } | |
466 | ||
467 | static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel, | |
468 | Elf_Sym *sym, const char *symname)) | |
469 | { | |
470 | int i; | |
471 | ||
472 | /* Walk through the relocations */ | |
473 | for (i = 0; i < ehdr.e_shnum; i++) { | |
474 | char *sym_strtab; | |
475 | Elf_Sym *sh_symtab; | |
476 | struct section *sec_applies, *sec_symtab; | |
477 | int j; | |
478 | struct section *sec = &secs[i]; | |
479 | ||
480 | if (sec->shdr.sh_type != SHT_REL_TYPE) | |
481 | continue; | |
482 | ||
483 | sec_symtab = sec->link; | |
484 | sec_applies = &secs[sec->shdr.sh_info]; | |
485 | if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) | |
486 | continue; | |
487 | ||
488 | sh_symtab = sec_symtab->symtab; | |
489 | sym_strtab = sec_symtab->link->strtab; | |
490 | for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) { | |
491 | Elf_Rel *rel = &sec->reltab[j]; | |
492 | Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)]; | |
493 | const char *symname = sym_name(sym_strtab, sym); | |
494 | ||
495 | process(sec, rel, sym, symname); | |
496 | } | |
497 | } | |
498 | } | |
499 | ||
500 | static int do_reloc(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, | |
501 | const char *symname) | |
502 | { | |
503 | unsigned r_type = ELF_R_TYPE(rel->r_info); | |
504 | unsigned bind = ELF_ST_BIND(sym->st_info); | |
505 | ||
506 | if ((bind == STB_WEAK) && (sym->st_value == 0)) { | |
507 | /* Don't relocate weak symbols without a target */ | |
508 | return 0; | |
509 | } | |
510 | ||
511 | if (regex_skip_reloc(symname)) | |
512 | return 0; | |
513 | ||
514 | switch (r_type) { | |
515 | case R_MIPS_NONE: | |
516 | case R_MIPS_REL32: | |
517 | case R_MIPS_PC16: | |
518 | case R_MIPS_PC21_S2: | |
519 | case R_MIPS_PC26_S2: | |
520 | /* | |
521 | * NONE can be ignored and PC relative relocations don't | |
522 | * need to be adjusted. | |
523 | */ | |
524 | case R_MIPS_HIGHEST: | |
525 | case R_MIPS_HIGHER: | |
526 | /* We support relocating within the same 4Gb segment only, | |
527 | * thus leaving the top 32bits unchanged | |
528 | */ | |
529 | case R_MIPS_LO16: | |
530 | /* We support relocating by 64k jumps only | |
531 | * thus leaving the bottom 16bits unchanged | |
532 | */ | |
533 | break; | |
534 | ||
535 | case R_MIPS_64: | |
536 | case R_MIPS_32: | |
537 | case R_MIPS_26: | |
538 | case R_MIPS_HI16: | |
539 | add_reloc(&relocs, rel->r_offset, r_type); | |
540 | break; | |
541 | ||
542 | default: | |
543 | die("Unsupported relocation type: %s (%d)\n", | |
544 | rel_type(r_type), r_type); | |
545 | break; | |
546 | } | |
547 | ||
548 | return 0; | |
549 | } | |
550 | ||
551 | static int write_reloc_as_bin(uint32_t v, FILE *f) | |
552 | { | |
553 | unsigned char buf[4]; | |
554 | ||
555 | v = cpu_to_elf32(v); | |
556 | ||
557 | memcpy(buf, &v, sizeof(uint32_t)); | |
558 | return fwrite(buf, 1, 4, f); | |
559 | } | |
560 | ||
561 | static int write_reloc_as_text(uint32_t v, FILE *f) | |
562 | { | |
563 | int res; | |
564 | ||
565 | res = fprintf(f, "\t.long 0x%08"PRIx32"\n", v); | |
566 | if (res < 0) | |
567 | return res; | |
568 | else | |
569 | return sizeof(uint32_t); | |
570 | } | |
571 | ||
572 | static void emit_relocs(int as_text, int as_bin, FILE *outf) | |
573 | { | |
574 | int i; | |
575 | int (*write_reloc)(uint32_t, FILE *) = write_reloc_as_bin; | |
576 | int size = 0; | |
577 | int size_reserved; | |
578 | struct section *sec_reloc; | |
579 | ||
580 | sec_reloc = sec_lookup(".data.reloc"); | |
581 | if (!sec_reloc) | |
582 | die("Could not find relocation section\n"); | |
583 | ||
584 | size_reserved = sec_reloc->shdr.sh_size; | |
585 | ||
586 | /* Collect up the relocations */ | |
587 | walk_relocs(do_reloc); | |
588 | ||
589 | /* Print the relocations */ | |
590 | if (as_text) { | |
591 | /* Print the relocations in a form suitable that | |
592 | * gas will like. | |
593 | */ | |
594 | printf(".section \".data.reloc\",\"a\"\n"); | |
595 | printf(".balign 4\n"); | |
596 | /* Output text to stdout */ | |
597 | write_reloc = write_reloc_as_text; | |
598 | outf = stdout; | |
599 | } else if (as_bin) { | |
600 | /* Output raw binary to stdout */ | |
601 | outf = stdout; | |
602 | } else { | |
603 | /* Seek to offset of the relocation section. | |
604 | * Each relocation is then written into the | |
605 | * vmlinux kernel image. | |
606 | */ | |
607 | if (fseek(outf, sec_reloc->shdr.sh_offset, SEEK_SET) < 0) { | |
608 | die("Seek to %d failed: %s\n", | |
609 | sec_reloc->shdr.sh_offset, strerror(errno)); | |
610 | } | |
611 | } | |
612 | ||
613 | for (i = 0; i < relocs.count; i++) | |
614 | size += write_reloc(relocs.offset[i], outf); | |
615 | ||
616 | /* Print a stop, but only if we've actually written some relocs */ | |
617 | if (size) | |
618 | size += write_reloc(0, outf); | |
619 | ||
620 | if (size > size_reserved) | |
621 | /* Die, but suggest a value for CONFIG_RELOCATION_TABLE_SIZE | |
622 | * which will fix this problem and allow a bit of headroom | |
623 | * if more kernel features are enabled | |
624 | */ | |
625 | die("Relocations overflow available space!\n" \ | |
626 | "Please adjust CONFIG_RELOCATION_TABLE_SIZE " \ | |
627 | "to at least 0x%08x\n", (size + 0x1000) & ~0xFFF); | |
628 | } | |
629 | ||
630 | /* | |
631 | * As an aid to debugging problems with different linkers | |
632 | * print summary information about the relocs. | |
633 | * Since different linkers tend to emit the sections in | |
634 | * different orders we use the section names in the output. | |
635 | */ | |
636 | static int do_reloc_info(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym, | |
637 | const char *symname) | |
638 | { | |
639 | printf("%16s 0x%08x %16s %40s %16s\n", | |
640 | sec_name(sec->shdr.sh_info), | |
641 | (unsigned int)rel->r_offset, | |
642 | rel_type(ELF_R_TYPE(rel->r_info)), | |
643 | symname, | |
644 | sec_name(sym->st_shndx)); | |
645 | return 0; | |
646 | } | |
647 | ||
648 | static void print_reloc_info(void) | |
649 | { | |
650 | printf("%16s %10s %16s %40s %16s\n", | |
651 | "reloc section", | |
652 | "offset", | |
653 | "reloc type", | |
654 | "symbol", | |
655 | "symbol section"); | |
656 | walk_relocs(do_reloc_info); | |
657 | } | |
658 | ||
659 | #if ELF_BITS == 64 | |
660 | # define process process_64 | |
661 | #else | |
662 | # define process process_32 | |
663 | #endif | |
664 | ||
665 | void process(FILE *fp, int as_text, int as_bin, | |
666 | int show_reloc_info, int keep_relocs) | |
667 | { | |
668 | regex_init(); | |
669 | read_ehdr(fp); | |
670 | read_shdrs(fp); | |
671 | read_strtabs(fp); | |
672 | read_symtabs(fp); | |
673 | read_relocs(fp); | |
674 | if (show_reloc_info) { | |
675 | print_reloc_info(); | |
676 | return; | |
677 | } | |
678 | emit_relocs(as_text, as_bin, fp); | |
679 | if (!keep_relocs) | |
680 | remove_relocs(fp); | |
681 | } |