]>
Commit | Line | Data |
---|---|---|
61ba1cf9 ILT |
1 | // reloc.cc -- relocate input files for gold. |
2 | ||
3 | #include "gold.h" | |
4 | ||
5 | #include "workqueue.h" | |
6 | #include "object.h" | |
7 | #include "output.h" | |
8 | #include "reloc.h" | |
9 | ||
10 | namespace gold | |
11 | { | |
12 | ||
92e059d8 ILT |
13 | // Read_relocs methods. |
14 | ||
15 | // These tasks just read the relocation information from the file. | |
16 | // After reading it, the start another task to process the | |
17 | // information. These tasks requires access to the file. | |
18 | ||
19 | Task::Is_runnable_type | |
20 | Read_relocs::is_runnable(Workqueue*) | |
21 | { | |
22 | return this->object_->is_locked() ? IS_LOCKED : IS_RUNNABLE; | |
23 | } | |
24 | ||
25 | // Lock the file. | |
26 | ||
27 | Task_locker* | |
28 | Read_relocs::locks(Workqueue*) | |
29 | { | |
30 | return new Task_locker_obj<Object>(*this->object_); | |
31 | } | |
32 | ||
33 | // Read the relocations and then start a Scan_relocs_task. | |
34 | ||
35 | void | |
36 | Read_relocs::run(Workqueue* workqueue) | |
37 | { | |
38 | Read_relocs_data *rd = new Read_relocs_data; | |
39 | this->object_->read_relocs(rd); | |
40 | workqueue->queue_front(new Scan_relocs(this->options_, this->symtab_, | |
41 | this->object_, rd, this->symtab_lock_, | |
42 | this->blocker_)); | |
43 | } | |
44 | ||
45 | // Scan_relocs methods. | |
46 | ||
47 | // These tasks scan the relocations read by Read_relocs and mark up | |
48 | // the symbol table to indicate which relocations are required. We | |
49 | // use a lock on the symbol table to keep them from interfering with | |
50 | // each other. | |
51 | ||
52 | Task::Is_runnable_type | |
53 | Scan_relocs::is_runnable(Workqueue*) | |
54 | { | |
55 | return this->symtab_lock_->is_writable() ? IS_RUNNABLE : IS_LOCKED; | |
56 | } | |
57 | ||
58 | // Return the locks we hold: one on the file, one on the symbol table | |
59 | // and one blocker. | |
60 | ||
61 | class Scan_relocs::Scan_relocs_locker : public Task_locker | |
62 | { | |
63 | public: | |
64 | Scan_relocs_locker(Object* object, Task_token& symtab_lock, Task* task, | |
65 | Task_token& blocker, Workqueue* workqueue) | |
66 | : objlock_(*object), symtab_locker_(symtab_lock, task), | |
67 | blocker_(blocker, workqueue) | |
68 | { } | |
69 | ||
70 | private: | |
71 | Task_locker_obj<Object> objlock_; | |
72 | Task_locker_write symtab_locker_; | |
73 | Task_locker_block blocker_; | |
74 | }; | |
75 | ||
76 | Task_locker* | |
77 | Scan_relocs::locks(Workqueue* workqueue) | |
78 | { | |
79 | return new Scan_relocs_locker(this->object_, *this->symtab_lock_, this, | |
80 | *this->blocker_, workqueue); | |
81 | } | |
82 | ||
83 | // Scan the relocs. | |
84 | ||
85 | void | |
86 | Scan_relocs::run(Workqueue*) | |
87 | { | |
88 | this->object_->scan_relocs(this->options_, this->symtab_, this->rd_); | |
89 | delete this->rd_; | |
90 | this->rd_ = NULL; | |
91 | } | |
92 | ||
61ba1cf9 ILT |
93 | // Relocate_task methods. |
94 | ||
95 | // These tasks are always runnable. | |
96 | ||
97 | Task::Is_runnable_type | |
98 | Relocate_task::is_runnable(Workqueue*) | |
99 | { | |
100 | return IS_RUNNABLE; | |
101 | } | |
102 | ||
103 | // We want to lock the file while we run. We want to unblock | |
104 | // FINAL_BLOCKER when we are done. | |
105 | ||
106 | class Relocate_task::Relocate_locker : public Task_locker | |
107 | { | |
108 | public: | |
109 | Relocate_locker(Task_token& token, Workqueue* workqueue, | |
110 | Object* object) | |
111 | : blocker_(token, workqueue), objlock_(*object) | |
112 | { } | |
113 | ||
114 | private: | |
115 | Task_locker_block blocker_; | |
116 | Task_locker_obj<Object> objlock_; | |
117 | }; | |
118 | ||
119 | Task_locker* | |
120 | Relocate_task::locks(Workqueue* workqueue) | |
121 | { | |
122 | return new Relocate_locker(*this->final_blocker_, workqueue, | |
123 | this->object_); | |
124 | } | |
125 | ||
126 | // Run the task. | |
127 | ||
128 | void | |
129 | Relocate_task::run(Workqueue*) | |
130 | { | |
92e059d8 | 131 | this->object_->relocate(this->options_, this->symtab_, this->layout_, |
61ba1cf9 ILT |
132 | this->of_); |
133 | } | |
134 | ||
92e059d8 ILT |
135 | // Read the relocs and local symbols from the object file and store |
136 | // the information in RD. | |
137 | ||
138 | template<int size, bool big_endian> | |
139 | void | |
140 | Sized_object<size, big_endian>::do_read_relocs(Read_relocs_data* rd) | |
141 | { | |
142 | rd->relocs.clear(); | |
143 | ||
144 | unsigned int shnum = this->shnum(); | |
145 | if (shnum == 0) | |
146 | return; | |
147 | ||
148 | rd->relocs.reserve(shnum / 2); | |
149 | ||
150 | const unsigned char *pshdrs = this->get_view(this->shoff_, | |
151 | shnum * This::shdr_size); | |
152 | // Skip the first, dummy, section. | |
153 | const unsigned char *ps = pshdrs + This::shdr_size; | |
154 | for (unsigned int i = 1; i < shnum; ++i, ps += This::shdr_size) | |
155 | { | |
156 | typename This::Shdr shdr(ps); | |
157 | ||
158 | unsigned int sh_type = shdr.get_sh_type(); | |
159 | if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA) | |
160 | continue; | |
161 | ||
162 | unsigned int shndx = shdr.get_sh_info(); | |
163 | if (shndx >= shnum) | |
164 | { | |
165 | fprintf(stderr, _("%s: %s: relocation section %u has bad info %u\n"), | |
166 | program_name, this->name().c_str(), i, shndx); | |
167 | gold_exit(false); | |
168 | } | |
169 | ||
170 | if (!this->is_section_included(shndx)) | |
171 | continue; | |
172 | ||
173 | if (shdr.get_sh_link() != this->symtab_shnum_) | |
174 | { | |
175 | fprintf(stderr, | |
176 | _("%s: %s: relocation section %u uses unexpected " | |
177 | "symbol table %u\n"), | |
178 | program_name, this->name().c_str(), i, shdr.get_sh_link()); | |
179 | gold_exit(false); | |
180 | } | |
181 | ||
182 | off_t sh_size = shdr.get_sh_size(); | |
183 | ||
184 | unsigned int reloc_size; | |
185 | if (sh_type == elfcpp::SHT_REL) | |
186 | reloc_size = elfcpp::Elf_sizes<size>::rel_size; | |
187 | else | |
188 | reloc_size = elfcpp::Elf_sizes<size>::rela_size; | |
189 | if (reloc_size != shdr.get_sh_entsize()) | |
190 | { | |
191 | fprintf(stderr, | |
192 | _("%s: %s: unexpected entsize for reloc section %u: " | |
193 | "%lu != %u"), | |
194 | program_name, this->name().c_str(), i, | |
195 | static_cast<unsigned long>(shdr.get_sh_entsize()), | |
196 | reloc_size); | |
197 | gold_exit(false); | |
198 | } | |
199 | ||
200 | size_t reloc_count = sh_size / reloc_size; | |
201 | if (reloc_count * reloc_size != sh_size) | |
202 | { | |
203 | fprintf(stderr, _("%s: %s: reloc section %u size %lu uneven"), | |
204 | program_name, this->name().c_str(), i, | |
205 | static_cast<unsigned long>(sh_size)); | |
206 | gold_exit(false); | |
207 | } | |
208 | ||
209 | rd->relocs.push_back(Section_relocs()); | |
210 | Section_relocs& sr(rd->relocs.back()); | |
211 | sr.reloc_shndx = i; | |
212 | sr.data_shndx = shndx; | |
213 | sr.contents = this->get_lasting_view(shdr.get_sh_offset(), sh_size); | |
214 | sr.sh_type = sh_type; | |
215 | sr.reloc_count = reloc_count; | |
216 | } | |
217 | ||
218 | // Read the local symbols. | |
219 | if (this->symtab_shnum_ == 0 || this->local_symbol_count_ == 0) | |
220 | rd->local_symbols = NULL; | |
221 | else | |
222 | { | |
223 | typename This::Shdr symtabshdr(pshdrs | |
224 | + this->symtab_shnum_ * This::shdr_size); | |
225 | assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); | |
226 | const int sym_size = This::sym_size; | |
227 | const unsigned int loccount = this->local_symbol_count_; | |
228 | assert(loccount == symtabshdr.get_sh_info()); | |
229 | off_t locsize = loccount * sym_size; | |
230 | rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(), | |
231 | locsize); | |
232 | } | |
233 | } | |
234 | ||
235 | // Scan the relocs and adjust the symbol table. This looks for | |
236 | // relocations which require GOT/PLT/COPY relocations. | |
237 | ||
238 | template<int size, bool big_endian> | |
239 | void | |
240 | Sized_object<size, big_endian>::do_scan_relocs(const General_options& options, | |
241 | Symbol_table* symtab, | |
242 | Read_relocs_data* rd) | |
243 | { | |
244 | Sized_target<size, big_endian>* target = this->sized_target(); | |
245 | ||
246 | const unsigned char* local_symbols; | |
247 | if (rd->local_symbols == NULL) | |
248 | local_symbols = NULL; | |
249 | else | |
250 | local_symbols = rd->local_symbols->data(); | |
251 | ||
252 | for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin(); | |
253 | p != rd->relocs.end(); | |
254 | ++p) | |
255 | { | |
256 | target->scan_relocs(options, symtab, this, p->sh_type, | |
257 | p->contents->data(), p->reloc_count, | |
258 | this->local_symbol_count_, | |
259 | local_symbols, | |
260 | this->symbols_); | |
261 | delete p->contents; | |
262 | p->contents = NULL; | |
263 | } | |
264 | ||
265 | if (rd->local_symbols != NULL) | |
266 | { | |
267 | delete rd->local_symbols; | |
268 | rd->local_symbols = NULL; | |
269 | } | |
270 | } | |
271 | ||
61ba1cf9 ILT |
272 | // Relocate the input sections and write out the local symbols. |
273 | ||
274 | template<int size, bool big_endian> | |
275 | void | |
92e059d8 | 276 | Sized_object<size, big_endian>::do_relocate(const General_options& options, |
61ba1cf9 | 277 | const Symbol_table* symtab, |
92e059d8 | 278 | const Layout* layout, |
61ba1cf9 ILT |
279 | Output_file* of) |
280 | { | |
281 | unsigned int shnum = this->shnum(); | |
282 | ||
283 | // Read the section headers. | |
284 | const unsigned char* pshdrs = this->get_view(this->shoff_, | |
285 | shnum * This::shdr_size); | |
286 | ||
287 | Views views; | |
288 | views.resize(shnum); | |
289 | ||
290 | // Make two passes over the sections. The first one copies the | |
291 | // section data to the output file. The second one applies | |
292 | // relocations. | |
293 | ||
294 | this->write_sections(pshdrs, of, &views); | |
295 | ||
296 | // Apply relocations. | |
297 | ||
92e059d8 | 298 | this->relocate_sections(options, symtab, layout, pshdrs, &views); |
61ba1cf9 ILT |
299 | |
300 | // Write out the accumulated views. | |
301 | for (unsigned int i = 1; i < shnum; ++i) | |
302 | { | |
303 | if (views[i].view != NULL) | |
304 | of->write_output_view(views[i].offset, views[i].view_size, | |
305 | views[i].view); | |
306 | } | |
307 | ||
308 | // Write out the local symbols. | |
92e059d8 | 309 | this->write_local_symbols(of, layout->sympool()); |
61ba1cf9 ILT |
310 | } |
311 | ||
312 | // Write section data to the output file. PSHDRS points to the | |
313 | // section headers. Record the views in *PVIEWS for use when | |
314 | // relocating. | |
315 | ||
316 | template<int size, bool big_endian> | |
317 | void | |
318 | Sized_object<size, big_endian>::write_sections(const unsigned char* pshdrs, | |
319 | Output_file* of, | |
320 | Views* pviews) | |
321 | { | |
322 | unsigned int shnum = this->shnum(); | |
323 | std::vector<Map_to_output>& map_sections(this->map_to_output()); | |
324 | ||
325 | const unsigned char* p = pshdrs + This::shdr_size; | |
326 | for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size) | |
327 | { | |
328 | View_size* pvs = &(*pviews)[i]; | |
329 | ||
330 | pvs->view = NULL; | |
331 | ||
332 | const Output_section* os = map_sections[i].output_section; | |
333 | if (os == NULL) | |
334 | continue; | |
335 | ||
336 | typename This::Shdr shdr(p); | |
337 | ||
338 | if (shdr.get_sh_type() == elfcpp::SHT_NOBITS) | |
339 | continue; | |
340 | ||
341 | assert(map_sections[i].offset >= 0 | |
342 | && map_sections[i].offset < os->data_size()); | |
343 | off_t start = os->offset() + map_sections[i].offset; | |
344 | off_t sh_size = shdr.get_sh_size(); | |
345 | ||
346 | unsigned char* view = of->get_output_view(start, sh_size); | |
92e059d8 ILT |
347 | this->read(shdr.get_sh_offset(), sh_size, view); |
348 | ||
61ba1cf9 ILT |
349 | pvs->view = view; |
350 | pvs->address = os->address() + map_sections[i].offset; | |
351 | pvs->offset = start; | |
352 | pvs->view_size = sh_size; | |
353 | } | |
354 | } | |
355 | ||
356 | // Relocate section data. VIEWS points to the section data as views | |
357 | // in the output file. | |
358 | ||
359 | template<int size, bool big_endian> | |
360 | void | |
92e059d8 ILT |
361 | Sized_object<size, big_endian>::relocate_sections( |
362 | const General_options& options, | |
363 | const Symbol_table* symtab, | |
364 | const Layout* layout, | |
365 | const unsigned char* pshdrs, | |
366 | Views* pviews) | |
61ba1cf9 ILT |
367 | { |
368 | unsigned int shnum = this->shnum(); | |
61ba1cf9 ILT |
369 | Sized_target<size, big_endian>* target = this->sized_target(); |
370 | ||
92e059d8 ILT |
371 | Relocate_info<size, big_endian> relinfo; |
372 | relinfo.options = &options; | |
373 | relinfo.symtab = symtab; | |
374 | relinfo.layout = layout; | |
375 | relinfo.object = this; | |
376 | relinfo.local_symbol_count = this->local_symbol_count_; | |
377 | relinfo.values = this->values_; | |
378 | relinfo.symbols = this->symbols_; | |
379 | ||
61ba1cf9 ILT |
380 | const unsigned char* p = pshdrs + This::shdr_size; |
381 | for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size) | |
382 | { | |
383 | typename This::Shdr shdr(p); | |
384 | ||
385 | unsigned int sh_type = shdr.get_sh_type(); | |
386 | if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA) | |
387 | continue; | |
388 | ||
389 | unsigned int index = shdr.get_sh_info(); | |
390 | if (index >= this->shnum()) | |
391 | { | |
392 | fprintf(stderr, _("%s: %s: relocation section %u has bad info %u\n"), | |
393 | program_name, this->name().c_str(), i, index); | |
394 | gold_exit(false); | |
395 | } | |
396 | ||
92e059d8 | 397 | if (!this->is_section_included(index)) |
61ba1cf9 ILT |
398 | { |
399 | // This relocation section is against a section which we | |
400 | // discarded. | |
401 | continue; | |
402 | } | |
403 | ||
404 | assert((*pviews)[index].view != NULL); | |
405 | ||
406 | if (shdr.get_sh_link() != this->symtab_shnum_) | |
407 | { | |
408 | fprintf(stderr, | |
409 | _("%s: %s: relocation section %u uses unexpected " | |
410 | "symbol table %u\n"), | |
411 | program_name, this->name().c_str(), i, shdr.get_sh_link()); | |
412 | gold_exit(false); | |
413 | } | |
414 | ||
415 | off_t sh_size = shdr.get_sh_size(); | |
416 | const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(), | |
417 | sh_size); | |
418 | ||
419 | unsigned int reloc_size; | |
420 | if (sh_type == elfcpp::SHT_REL) | |
421 | reloc_size = elfcpp::Elf_sizes<size>::rel_size; | |
422 | else | |
423 | reloc_size = elfcpp::Elf_sizes<size>::rela_size; | |
424 | ||
425 | if (reloc_size != shdr.get_sh_entsize()) | |
426 | { | |
427 | fprintf(stderr, | |
428 | _("%s: %s: unexpected entsize for reloc section %u: " | |
429 | "%lu != %u"), | |
430 | program_name, this->name().c_str(), i, | |
431 | static_cast<unsigned long>(shdr.get_sh_entsize()), | |
432 | reloc_size); | |
433 | gold_exit(false); | |
434 | } | |
435 | ||
436 | size_t reloc_count = sh_size / reloc_size; | |
437 | if (reloc_count * reloc_size != sh_size) | |
438 | { | |
439 | fprintf(stderr, _("%s: %s: reloc section %u size %lu uneven"), | |
440 | program_name, this->name().c_str(), i, | |
441 | static_cast<unsigned long>(sh_size)); | |
442 | gold_exit(false); | |
443 | } | |
444 | ||
92e059d8 ILT |
445 | relinfo.reloc_shndx = i; |
446 | relinfo.data_shndx = index; | |
447 | target->relocate_section(&relinfo, | |
448 | sh_type, | |
449 | prelocs, | |
450 | reloc_count, | |
61ba1cf9 ILT |
451 | (*pviews)[index].view, |
452 | (*pviews)[index].address, | |
453 | (*pviews)[index].view_size); | |
454 | } | |
455 | } | |
456 | ||
457 | // Instantiate the templates we need. We could use the configure | |
458 | // script to restrict this to only the ones for implemented targets. | |
459 | ||
92e059d8 ILT |
460 | template |
461 | void | |
462 | Sized_object<32, false>::do_read_relocs(Read_relocs_data* rd); | |
463 | ||
464 | template | |
465 | void | |
466 | Sized_object<32, true>::do_read_relocs(Read_relocs_data* rd); | |
467 | ||
468 | template | |
469 | void | |
470 | Sized_object<64, false>::do_read_relocs(Read_relocs_data* rd); | |
471 | ||
472 | template | |
473 | void | |
474 | Sized_object<64, true>::do_read_relocs(Read_relocs_data* rd); | |
475 | ||
476 | template | |
477 | void | |
478 | Sized_object<32, false>::do_scan_relocs(const General_options& options, | |
479 | Symbol_table* symtab, | |
480 | Read_relocs_data* rd); | |
481 | ||
482 | template | |
483 | void | |
484 | Sized_object<32, true>::do_scan_relocs(const General_options& options, | |
485 | Symbol_table* symtab, | |
486 | Read_relocs_data* rd); | |
487 | ||
488 | template | |
489 | void | |
490 | Sized_object<64, false>::do_scan_relocs(const General_options& options, | |
491 | Symbol_table* symtab, | |
492 | Read_relocs_data* rd); | |
493 | ||
494 | template | |
495 | void | |
496 | Sized_object<64, true>::do_scan_relocs(const General_options& options, | |
497 | Symbol_table* symtab, | |
498 | Read_relocs_data* rd); | |
499 | ||
61ba1cf9 ILT |
500 | template |
501 | void | |
502 | Sized_object<32, false>::do_relocate(const General_options& options, | |
503 | const Symbol_table* symtab, | |
92e059d8 | 504 | const Layout* layout, |
61ba1cf9 ILT |
505 | Output_file* of); |
506 | ||
507 | template | |
508 | void | |
509 | Sized_object<32, true>::do_relocate(const General_options& options, | |
510 | const Symbol_table* symtab, | |
92e059d8 | 511 | const Layout* layout, |
61ba1cf9 ILT |
512 | Output_file* of); |
513 | ||
514 | template | |
515 | void | |
516 | Sized_object<64, false>::do_relocate(const General_options& options, | |
517 | const Symbol_table* symtab, | |
92e059d8 | 518 | const Layout* layout, |
61ba1cf9 ILT |
519 | Output_file* of); |
520 | ||
521 | template | |
522 | void | |
523 | Sized_object<64, true>::do_relocate(const General_options& options, | |
524 | const Symbol_table* symtab, | |
92e059d8 | 525 | const Layout* layout, |
61ba1cf9 ILT |
526 | Output_file* of); |
527 | ||
528 | ||
529 | } // End namespace gold. |