1 /*
2 * Copyright 2014-2019 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24 #include "ac_rtld.h"
25
26 #include <gelf.h>
27 #include <libelf.h>
28 #include <stdarg.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32
33 #include "ac_binary.h"
34 #include "ac_gpu_info.h"
35 #include "util/u_dynarray.h"
36 #include "util/u_math.h"
37
38 // Old distributions may not have this enum constant
39 #define MY_EM_AMDGPU 224
40
41 #ifndef STT_AMDGPU_LDS
42 #define STT_AMDGPU_LDS 13 // this is deprecated -- remove
43 #endif
44
45 #ifndef SHN_AMDGPU_LDS
46 #define SHN_AMDGPU_LDS 0xff00
47 #endif
48
49 #ifndef R_AMDGPU_NONE
50 #define R_AMDGPU_NONE 0
51 #define R_AMDGPU_ABS32_LO 1
52 #define R_AMDGPU_ABS32_HI 2
53 #define R_AMDGPU_ABS64 3
54 #define R_AMDGPU_REL32 4
55 #define R_AMDGPU_REL64 5
56 #define R_AMDGPU_ABS32 6
57 #define R_AMDGPU_GOTPCREL 7
58 #define R_AMDGPU_GOTPCREL32_LO 8
59 #define R_AMDGPU_GOTPCREL32_HI 9
60 #define R_AMDGPU_REL32_LO 10
61 #define R_AMDGPU_REL32_HI 11
62 #define R_AMDGPU_RELATIVE64 13
63 #endif
64
65 /* For the UMR disassembler. */
66 #define DEBUGGER_END_OF_CODE_MARKER 0xbf9f0000 /* invalid instruction */
67 #define DEBUGGER_NUM_MARKERS 5
68
69 struct ac_rtld_section {
70 bool is_rx : 1;
71 bool is_pasted_text : 1;
72 uint64_t offset;
73 const char *name;
74 };
75
76 struct ac_rtld_part {
77 Elf *elf;
78 struct ac_rtld_section *sections;
79 unsigned num_sections;
80 };
81
report_erroraf(const char * fmt,va_list va)82 static void report_erroraf(const char *fmt, va_list va)
83 {
84 char *msg;
85 int ret = vasprintf(&msg, fmt, va);
86 if (ret < 0)
87 msg = "(vasprintf failed)";
88
89 fprintf(stderr, "ac_rtld error: %s\n", msg);
90
91 if (ret >= 0)
92 free(msg);
93 }
94
95 static void report_errorf(const char *fmt, ...) PRINTFLIKE(1, 2);
96
report_errorf(const char * fmt,...)97 static void report_errorf(const char *fmt, ...)
98 {
99 va_list va;
100 va_start(va, fmt);
101 report_erroraf(fmt, va);
102 va_end(va);
103 }
104
105 static void report_elf_errorf(const char *fmt, ...) PRINTFLIKE(1, 2);
106
report_elf_errorf(const char * fmt,...)107 static void report_elf_errorf(const char *fmt, ...)
108 {
109 va_list va;
110 va_start(va, fmt);
111 report_erroraf(fmt, va);
112 va_end(va);
113
114 fprintf(stderr, "ELF error: %s\n", elf_errmsg(elf_errno()));
115 }
116
117 /**
118 * Find a symbol in a dynarray of struct ac_rtld_symbol by \p name and shader
119 * \p part_idx.
120 */
find_symbol(const struct util_dynarray * symbols,const char * name,unsigned part_idx)121 static const struct ac_rtld_symbol *find_symbol(const struct util_dynarray *symbols,
122 const char *name, unsigned part_idx)
123 {
124 util_dynarray_foreach(symbols, struct ac_rtld_symbol, symbol) {
125 if ((symbol->part_idx == ~0u || symbol->part_idx == part_idx) &&
126 !strcmp(name, symbol->name))
127 return symbol;
128 }
129 return 0;
130 }
131
compare_symbol_by_align(const void * lhsp,const void * rhsp)132 static int compare_symbol_by_align(const void *lhsp, const void *rhsp)
133 {
134 const struct ac_rtld_symbol *lhs = lhsp;
135 const struct ac_rtld_symbol *rhs = rhsp;
136 if (rhs->align > lhs->align)
137 return 1;
138 if (rhs->align < lhs->align)
139 return -1;
140 return 0;
141 }
142
143 /**
144 * Sort the given symbol list by decreasing alignment and assign offsets.
145 */
layout_symbols(struct ac_rtld_symbol * symbols,unsigned num_symbols,uint64_t * ptotal_size)146 static bool layout_symbols(struct ac_rtld_symbol *symbols, unsigned num_symbols,
147 uint64_t *ptotal_size)
148 {
149 qsort(symbols, num_symbols, sizeof(*symbols), compare_symbol_by_align);
150
151 uint64_t total_size = *ptotal_size;
152
153 for (unsigned i = 0; i < num_symbols; ++i) {
154 struct ac_rtld_symbol *s = &symbols[i];
155 assert(util_is_power_of_two_nonzero(s->align));
156
157 total_size = align64(total_size, s->align);
158 s->offset = total_size;
159
160 if (total_size + s->size < total_size) {
161 report_errorf("%s: size overflow", __FUNCTION__);
162 return false;
163 }
164
165 total_size += s->size;
166 }
167
168 *ptotal_size = total_size;
169 return true;
170 }
171
172 /**
173 * Read LDS symbols from the given \p section of the ELF of \p part and append
174 * them to the LDS symbols list.
175 *
176 * Shared LDS symbols are filtered out.
177 */
read_private_lds_symbols(struct ac_rtld_binary * binary,unsigned part_idx,Elf_Scn * section,uint32_t * lds_end_align)178 static bool read_private_lds_symbols(struct ac_rtld_binary *binary,
179 unsigned part_idx,
180 Elf_Scn *section,
181 uint32_t *lds_end_align)
182 {
183 #define report_if(cond) \
184 do { \
185 if ((cond)) { \
186 report_errorf(#cond); \
187 return false; \
188 } \
189 } while (false)
190 #define report_elf_if(cond) \
191 do { \
192 if ((cond)) { \
193 report_elf_errorf(#cond); \
194 return false; \
195 } \
196 } while (false)
197
198 struct ac_rtld_part *part = &binary->parts[part_idx];
199 Elf64_Shdr *shdr = elf64_getshdr(section);
200 uint32_t strtabidx = shdr->sh_link;
201 Elf_Data *symbols_data = elf_getdata(section, NULL);
202 report_elf_if(!symbols_data);
203
204 const Elf64_Sym *symbol = symbols_data->d_buf;
205 size_t num_symbols = symbols_data->d_size / sizeof(Elf64_Sym);
206
207 for (size_t j = 0; j < num_symbols; ++j, ++symbol) {
208 struct ac_rtld_symbol s = {};
209
210 if (ELF64_ST_TYPE(symbol->st_info) == STT_AMDGPU_LDS) {
211 /* old-style LDS symbols from initial prototype -- remove eventually */
212 s.align = MIN2(1u << (symbol->st_other >> 3), 1u << 16);
213 } else if (symbol->st_shndx == SHN_AMDGPU_LDS) {
214 s.align = MIN2(symbol->st_value, 1u << 16);
215 report_if(!util_is_power_of_two_nonzero(s.align));
216 } else
217 continue;
218
219 report_if(symbol->st_size > 1u << 29);
220
221 s.name = elf_strptr(part->elf, strtabidx, symbol->st_name);
222 s.size = symbol->st_size;
223 s.part_idx = part_idx;
224
225 if (!strcmp(s.name, "__lds_end")) {
226 report_elf_if(s.size != 0);
227 *lds_end_align = MAX2(*lds_end_align, s.align);
228 continue;
229 }
230
231 const struct ac_rtld_symbol *shared =
232 find_symbol(&binary->lds_symbols, s.name, part_idx);
233 if (shared) {
234 report_elf_if(s.align > shared->align);
235 report_elf_if(s.size > shared->size);
236 continue;
237 }
238
239 util_dynarray_append(&binary->lds_symbols, struct ac_rtld_symbol, s);
240 }
241
242 return true;
243
244 #undef report_if
245 #undef report_elf_if
246 }
247
248 /**
249 * Open a binary consisting of one or more shader parts.
250 *
251 * \param binary the uninitialized struct
252 * \param i binary opening parameters
253 */
ac_rtld_open(struct ac_rtld_binary * binary,struct ac_rtld_open_info i)254 bool ac_rtld_open(struct ac_rtld_binary *binary,
255 struct ac_rtld_open_info i)
256 {
257 /* One of the libelf implementations
258 * (http://www.mr511.de/software/english.htm) requires calling
259 * elf_version() before elf_memory().
260 */
261 elf_version(EV_CURRENT);
262
263 memset(binary, 0, sizeof(*binary));
264 memcpy(&binary->options, &i.options, sizeof(binary->options));
265 binary->wave_size = i.wave_size;
266 binary->num_parts = i.num_parts;
267 binary->parts = calloc(sizeof(*binary->parts), i.num_parts);
268 if (!binary->parts)
269 return false;
270
271 uint64_t pasted_text_size = 0;
272 uint64_t rx_align = 1;
273 uint64_t rx_size = 0;
274 uint64_t exec_size = 0;
275
276 #define report_if(cond) \
277 do { \
278 if ((cond)) { \
279 report_errorf(#cond); \
280 goto fail; \
281 } \
282 } while (false)
283 #define report_elf_if(cond) \
284 do { \
285 if ((cond)) { \
286 report_elf_errorf(#cond); \
287 goto fail; \
288 } \
289 } while (false)
290
291 /* Copy and layout shared LDS symbols. */
292 if (i.num_shared_lds_symbols) {
293 if (!util_dynarray_resize(&binary->lds_symbols, struct ac_rtld_symbol,
294 i.num_shared_lds_symbols))
295 goto fail;
296
297 memcpy(binary->lds_symbols.data, i.shared_lds_symbols, binary->lds_symbols.size);
298 }
299
300 util_dynarray_foreach(&binary->lds_symbols, struct ac_rtld_symbol, symbol)
301 symbol->part_idx = ~0u;
302
303 unsigned max_lds_size = 64 * 1024;
304
305 if (i.info->chip_class == GFX6 ||
306 (i.shader_type != MESA_SHADER_COMPUTE &&
307 i.shader_type != MESA_SHADER_FRAGMENT))
308 max_lds_size = 32 * 1024;
309
310 uint64_t shared_lds_size = 0;
311 if (!layout_symbols(binary->lds_symbols.data, i.num_shared_lds_symbols, &shared_lds_size))
312 goto fail;
313
314 if (shared_lds_size > max_lds_size) {
315 fprintf(stderr, "ac_rtld error(1): too much LDS (used = %u, max = %u)\n",
316 (unsigned)shared_lds_size, max_lds_size);
317 goto fail;
318 }
319 binary->lds_size = shared_lds_size;
320
321 /* First pass over all parts: open ELFs, pre-determine the placement of
322 * sections in the memory image, and collect and layout private LDS symbols. */
323 uint32_t lds_end_align = 0;
324
325 if (binary->options.halt_at_entry)
326 pasted_text_size += 4;
327
328 for (unsigned part_idx = 0; part_idx < i.num_parts; ++part_idx) {
329 struct ac_rtld_part *part = &binary->parts[part_idx];
330 unsigned part_lds_symbols_begin =
331 util_dynarray_num_elements(&binary->lds_symbols, struct ac_rtld_symbol);
332
333 part->elf = elf_memory((char *)i.elf_ptrs[part_idx], i.elf_sizes[part_idx]);
334 report_elf_if(!part->elf);
335
336 const Elf64_Ehdr *ehdr = elf64_getehdr(part->elf);
337 report_elf_if(!ehdr);
338 report_if(ehdr->e_machine != MY_EM_AMDGPU);
339
340 size_t section_str_index;
341 size_t num_shdrs;
342 report_elf_if(elf_getshdrstrndx(part->elf, §ion_str_index) < 0);
343 report_elf_if(elf_getshdrnum(part->elf, &num_shdrs) < 0);
344
345 part->num_sections = num_shdrs;
346 part->sections = calloc(sizeof(*part->sections), num_shdrs);
347 report_if(!part->sections);
348
349 Elf_Scn *section = NULL;
350 while ((section = elf_nextscn(part->elf, section))) {
351 Elf64_Shdr *shdr = elf64_getshdr(section);
352 struct ac_rtld_section *s = &part->sections[elf_ndxscn(section)];
353 s->name = elf_strptr(part->elf, section_str_index, shdr->sh_name);
354 report_elf_if(!s->name);
355
356 /* Cannot actually handle linked objects yet */
357 report_elf_if(shdr->sh_addr != 0);
358
359 /* Alignment must be 0 or a power of two */
360 report_elf_if(shdr->sh_addralign & (shdr->sh_addralign - 1));
361 uint64_t sh_align = MAX2(shdr->sh_addralign, 1);
362
363 if (shdr->sh_flags & SHF_ALLOC &&
364 shdr->sh_type != SHT_NOTE) {
365 report_if(shdr->sh_flags & SHF_WRITE);
366
367 s->is_rx = true;
368
369 if (shdr->sh_flags & SHF_EXECINSTR) {
370 report_elf_if(shdr->sh_size & 3);
371
372 if (!strcmp(s->name, ".text"))
373 s->is_pasted_text = true;
374
375 exec_size += shdr->sh_size;
376 }
377
378 if (s->is_pasted_text) {
379 s->offset = pasted_text_size;
380 pasted_text_size += shdr->sh_size;
381 } else {
382 rx_align = align(rx_align, sh_align);
383 rx_size = align(rx_size, sh_align);
384 s->offset = rx_size;
385 rx_size += shdr->sh_size;
386 }
387 } else if (shdr->sh_type == SHT_SYMTAB) {
388 if (!read_private_lds_symbols(binary, part_idx, section, &lds_end_align))
389 goto fail;
390 }
391 }
392
393 uint64_t part_lds_size = shared_lds_size;
394 if (!layout_symbols(
395 util_dynarray_element(&binary->lds_symbols, struct ac_rtld_symbol, part_lds_symbols_begin),
396 util_dynarray_num_elements(&binary->lds_symbols, struct ac_rtld_symbol) - part_lds_symbols_begin,
397 &part_lds_size))
398 goto fail;
399 binary->lds_size = MAX2(binary->lds_size, part_lds_size);
400 }
401
402 binary->rx_end_markers = pasted_text_size;
403 pasted_text_size += 4 * DEBUGGER_NUM_MARKERS;
404
405 /* __lds_end is a special symbol that points at the end of the memory
406 * occupied by other LDS symbols. Its alignment is taken as the
407 * maximum of its alignment over all shader parts where it occurs.
408 */
409 if (lds_end_align) {
410 binary->lds_size = align(binary->lds_size, lds_end_align);
411
412 struct ac_rtld_symbol *lds_end =
413 util_dynarray_grow(&binary->lds_symbols, struct ac_rtld_symbol, 1);
414 lds_end->name = "__lds_end";
415 lds_end->size = 0;
416 lds_end->align = lds_end_align;
417 lds_end->offset = binary->lds_size;
418 lds_end->part_idx = ~0u;
419 }
420
421 if (binary->lds_size > max_lds_size) {
422 fprintf(stderr, "ac_rtld error(2): too much LDS (used = %u, max = %u)\n",
423 (unsigned)binary->lds_size, max_lds_size);
424 goto fail;
425 }
426
427 /* Second pass: Adjust offsets of non-pasted text sections. */
428 binary->rx_size = pasted_text_size;
429 binary->rx_size = align(binary->rx_size, rx_align);
430
431 for (unsigned part_idx = 0; part_idx < i.num_parts; ++part_idx) {
432 struct ac_rtld_part *part = &binary->parts[part_idx];
433 size_t num_shdrs;
434 elf_getshdrnum(part->elf, &num_shdrs);
435
436 for (unsigned j = 0; j < num_shdrs; ++j) {
437 struct ac_rtld_section *s = &part->sections[j];
438 if (s->is_rx && !s->is_pasted_text)
439 s->offset += binary->rx_size;
440 }
441 }
442
443 binary->rx_size += rx_size;
444 binary->exec_size = exec_size;
445
446 if (i.info->chip_class >= GFX10) {
447 /* In gfx10, the SQ fetches up to 3 cache lines of 16 dwords
448 * ahead of the PC, configurable by SH_MEM_CONFIG and
449 * S_INST_PREFETCH. This can cause two issues:
450 *
451 * (1) Crossing a page boundary to an unmapped page. The logic
452 * does not distinguish between a required fetch and a "mere"
453 * prefetch and will fault.
454 *
455 * (2) Prefetching instructions that will be changed for a
456 * different shader.
457 *
458 * (2) is not currently an issue because we flush the I$ at IB
459 * boundaries, but (1) needs to be addressed. Due to buffer
460 * suballocation, we just play it safe.
461 */
462 binary->rx_size = align(binary->rx_size + 3 * 64, 64);
463 }
464
465 return true;
466
467 #undef report_if
468 #undef report_elf_if
469
470 fail:
471 ac_rtld_close(binary);
472 return false;
473 }
474
ac_rtld_close(struct ac_rtld_binary * binary)475 void ac_rtld_close(struct ac_rtld_binary *binary)
476 {
477 for (unsigned i = 0; i < binary->num_parts; ++i) {
478 struct ac_rtld_part *part = &binary->parts[i];
479 free(part->sections);
480 elf_end(part->elf);
481 }
482
483 util_dynarray_fini(&binary->lds_symbols);
484 free(binary->parts);
485 binary->parts = NULL;
486 binary->num_parts = 0;
487 }
488
get_section_by_name(struct ac_rtld_part * part,const char * name,const char ** data,size_t * nbytes)489 static bool get_section_by_name(struct ac_rtld_part *part, const char *name,
490 const char **data, size_t *nbytes)
491 {
492 for (unsigned i = 0; i < part->num_sections; ++i) {
493 struct ac_rtld_section *s = &part->sections[i];
494 if (s->name && !strcmp(name, s->name)) {
495 Elf_Scn *target_scn = elf_getscn(part->elf, i);
496 Elf_Data *target_data = elf_getdata(target_scn, NULL);
497 if (!target_data) {
498 report_elf_errorf("ac_rtld: get_section_by_name: elf_getdata");
499 return false;
500 }
501
502 *data = target_data->d_buf;
503 *nbytes = target_data->d_size;
504 return true;
505 }
506 }
507 return false;
508 }
509
ac_rtld_get_section_by_name(struct ac_rtld_binary * binary,const char * name,const char ** data,size_t * nbytes)510 bool ac_rtld_get_section_by_name(struct ac_rtld_binary *binary, const char *name,
511 const char **data, size_t *nbytes)
512 {
513 assert(binary->num_parts == 1);
514 return get_section_by_name(&binary->parts[0], name, data, nbytes);
515 }
516
ac_rtld_read_config(const struct radeon_info * info,struct ac_rtld_binary * binary,struct ac_shader_config * config)517 bool ac_rtld_read_config(const struct radeon_info *info,
518 struct ac_rtld_binary *binary,
519 struct ac_shader_config *config)
520 {
521 for (unsigned i = 0; i < binary->num_parts; ++i) {
522 struct ac_rtld_part *part = &binary->parts[i];
523 const char *config_data;
524 size_t config_nbytes;
525
526 if (!get_section_by_name(part, ".AMDGPU.config",
527 &config_data, &config_nbytes))
528 return false;
529
530 /* TODO: be precise about scratch use? */
531 struct ac_shader_config c = {};
532 ac_parse_shader_binary_config(config_data, config_nbytes,
533 binary->wave_size, true, info, &c);
534
535 config->num_sgprs = MAX2(config->num_sgprs, c.num_sgprs);
536 config->num_vgprs = MAX2(config->num_vgprs, c.num_vgprs);
537 config->spilled_sgprs = MAX2(config->spilled_sgprs, c.spilled_sgprs);
538 config->spilled_vgprs = MAX2(config->spilled_vgprs, c.spilled_vgprs);
539 config->scratch_bytes_per_wave = MAX2(config->scratch_bytes_per_wave,
540 c.scratch_bytes_per_wave);
541
542 assert(i == 0 || config->float_mode == c.float_mode);
543 config->float_mode = c.float_mode;
544
545 /* SPI_PS_INPUT_ENA/ADDR can't be combined. Only the value from
546 * the main shader part is used. */
547 assert(config->spi_ps_input_ena == 0 &&
548 config->spi_ps_input_addr == 0);
549 config->spi_ps_input_ena = c.spi_ps_input_ena;
550 config->spi_ps_input_addr = c.spi_ps_input_addr;
551
552 /* TODO: consistently use LDS symbols for this */
553 config->lds_size = MAX2(config->lds_size, c.lds_size);
554
555 /* TODO: Should we combine these somehow? It's currently only
556 * used for radeonsi's compute, where multiple parts aren't used. */
557 assert(config->rsrc1 == 0 && config->rsrc2 == 0);
558 config->rsrc1 = c.rsrc1;
559 config->rsrc2 = c.rsrc2;
560 }
561
562 return true;
563 }
564
resolve_symbol(const struct ac_rtld_upload_info * u,unsigned part_idx,const Elf64_Sym * sym,const char * name,uint64_t * value)565 static bool resolve_symbol(const struct ac_rtld_upload_info *u,
566 unsigned part_idx, const Elf64_Sym *sym,
567 const char *name, uint64_t *value)
568 {
569 /* TODO: properly disentangle the undef and the LDS cases once
570 * STT_AMDGPU_LDS is retired. */
571 if (sym->st_shndx == SHN_UNDEF || sym->st_shndx == SHN_AMDGPU_LDS) {
572 const struct ac_rtld_symbol *lds_sym =
573 find_symbol(&u->binary->lds_symbols, name, part_idx);
574
575 if (lds_sym) {
576 *value = lds_sym->offset;
577 return true;
578 }
579
580 /* TODO: resolve from other parts */
581
582 if (u->get_external_symbol(u->cb_data, name, value))
583 return true;
584
585 report_errorf("symbol %s: unknown", name);
586 return false;
587 }
588
589 struct ac_rtld_part *part = &u->binary->parts[part_idx];
590 if (sym->st_shndx >= part->num_sections) {
591 report_errorf("symbol %s: section out of bounds", name);
592 return false;
593 }
594
595 struct ac_rtld_section *s = &part->sections[sym->st_shndx];
596 if (!s->is_rx) {
597 report_errorf("symbol %s: bad section", name);
598 return false;
599 }
600
601 uint64_t section_base = u->rx_va + s->offset;
602
603 *value = section_base + sym->st_value;
604 return true;
605 }
606
apply_relocs(const struct ac_rtld_upload_info * u,unsigned part_idx,const Elf64_Shdr * reloc_shdr,const Elf_Data * reloc_data)607 static bool apply_relocs(const struct ac_rtld_upload_info *u,
608 unsigned part_idx, const Elf64_Shdr *reloc_shdr,
609 const Elf_Data *reloc_data)
610 {
611 #define report_if(cond) \
612 do { \
613 if ((cond)) { \
614 report_errorf(#cond); \
615 return false; \
616 } \
617 } while (false)
618 #define report_elf_if(cond) \
619 do { \
620 if ((cond)) { \
621 report_elf_errorf(#cond); \
622 return false; \
623 } \
624 } while (false)
625
626 struct ac_rtld_part *part = &u->binary->parts[part_idx];
627 Elf_Scn *target_scn = elf_getscn(part->elf, reloc_shdr->sh_info);
628 report_elf_if(!target_scn);
629
630 Elf_Data *target_data = elf_getdata(target_scn, NULL);
631 report_elf_if(!target_data);
632
633 Elf_Scn *symbols_scn = elf_getscn(part->elf, reloc_shdr->sh_link);
634 report_elf_if(!symbols_scn);
635
636 Elf64_Shdr *symbols_shdr = elf64_getshdr(symbols_scn);
637 report_elf_if(!symbols_shdr);
638 uint32_t strtabidx = symbols_shdr->sh_link;
639
640 Elf_Data *symbols_data = elf_getdata(symbols_scn, NULL);
641 report_elf_if(!symbols_data);
642
643 const Elf64_Sym *symbols = symbols_data->d_buf;
644 size_t num_symbols = symbols_data->d_size / sizeof(Elf64_Sym);
645
646 struct ac_rtld_section *s = &part->sections[reloc_shdr->sh_info];
647 report_if(!s->is_rx);
648
649 const char *orig_base = target_data->d_buf;
650 char *dst_base = u->rx_ptr + s->offset;
651 uint64_t va_base = u->rx_va + s->offset;
652
653 Elf64_Rel *rel = reloc_data->d_buf;
654 size_t num_relocs = reloc_data->d_size / sizeof(*rel);
655 for (size_t i = 0; i < num_relocs; ++i, ++rel) {
656 size_t r_sym = ELF64_R_SYM(rel->r_info);
657 unsigned r_type = ELF64_R_TYPE(rel->r_info);
658
659 const char *orig_ptr = orig_base + rel->r_offset;
660 char *dst_ptr = dst_base + rel->r_offset;
661 uint64_t va = va_base + rel->r_offset;
662
663 uint64_t symbol;
664 uint64_t addend;
665
666 if (r_sym == STN_UNDEF) {
667 symbol = 0;
668 } else {
669 report_elf_if(r_sym >= num_symbols);
670
671 const Elf64_Sym *sym = &symbols[r_sym];
672 const char *symbol_name =
673 elf_strptr(part->elf, strtabidx, sym->st_name);
674 report_elf_if(!symbol_name);
675
676 if (!resolve_symbol(u, part_idx, sym, symbol_name, &symbol))
677 return false;
678 }
679
680 /* TODO: Should we also support .rela sections, where the
681 * addend is part of the relocation record? */
682
683 /* Load the addend from the ELF instead of the destination,
684 * because the destination may be in VRAM. */
685 switch (r_type) {
686 case R_AMDGPU_ABS32:
687 case R_AMDGPU_ABS32_LO:
688 case R_AMDGPU_ABS32_HI:
689 case R_AMDGPU_REL32:
690 case R_AMDGPU_REL32_LO:
691 case R_AMDGPU_REL32_HI:
692 addend = *(const uint32_t *)orig_ptr;
693 break;
694 case R_AMDGPU_ABS64:
695 case R_AMDGPU_REL64:
696 addend = *(const uint64_t *)orig_ptr;
697 break;
698 default:
699 report_errorf("unsupported r_type == %u", r_type);
700 return false;
701 }
702
703 uint64_t abs = symbol + addend;
704
705 switch (r_type) {
706 case R_AMDGPU_ABS32:
707 assert((uint32_t)abs == abs);
708 case R_AMDGPU_ABS32_LO:
709 *(uint32_t *)dst_ptr = util_cpu_to_le32(abs);
710 break;
711 case R_AMDGPU_ABS32_HI:
712 *(uint32_t *)dst_ptr = util_cpu_to_le32(abs >> 32);
713 break;
714 case R_AMDGPU_ABS64:
715 *(uint64_t *)dst_ptr = util_cpu_to_le64(abs);
716 break;
717 case R_AMDGPU_REL32:
718 assert((int64_t)(int32_t)(abs - va) == (int64_t)(abs - va));
719 case R_AMDGPU_REL32_LO:
720 *(uint32_t *)dst_ptr = util_cpu_to_le32(abs - va);
721 break;
722 case R_AMDGPU_REL32_HI:
723 *(uint32_t *)dst_ptr = util_cpu_to_le32((abs - va) >> 32);
724 break;
725 case R_AMDGPU_REL64:
726 *(uint64_t *)dst_ptr = util_cpu_to_le64(abs - va);
727 break;
728 default:
729 unreachable("bad r_type");
730 }
731 }
732
733 return true;
734
735 #undef report_if
736 #undef report_elf_if
737 }
738
739 /**
740 * Upload the binary or binaries to the provided GPU buffers, including
741 * relocations.
742 */
ac_rtld_upload(struct ac_rtld_upload_info * u)743 bool ac_rtld_upload(struct ac_rtld_upload_info *u)
744 {
745 #define report_if(cond) \
746 do { \
747 if ((cond)) { \
748 report_errorf(#cond); \
749 return false; \
750 } \
751 } while (false)
752 #define report_elf_if(cond) \
753 do { \
754 if ((cond)) { \
755 report_errorf(#cond); \
756 return false; \
757 } \
758 } while (false)
759
760 if (u->binary->options.halt_at_entry) {
761 /* s_sethalt 1 */
762 *(uint32_t *)u->rx_ptr = util_cpu_to_le32(0xbf8d0001);
763 }
764
765 /* First pass: upload raw section data and lay out private LDS symbols. */
766 for (unsigned i = 0; i < u->binary->num_parts; ++i) {
767 struct ac_rtld_part *part = &u->binary->parts[i];
768
769 Elf_Scn *section = NULL;
770 while ((section = elf_nextscn(part->elf, section))) {
771 Elf64_Shdr *shdr = elf64_getshdr(section);
772 struct ac_rtld_section *s = &part->sections[elf_ndxscn(section)];
773
774 if (!s->is_rx)
775 continue;
776
777 report_if(shdr->sh_type != SHT_PROGBITS);
778
779 Elf_Data *data = elf_getdata(section, NULL);
780 report_elf_if(!data || data->d_size != shdr->sh_size);
781 memcpy(u->rx_ptr + s->offset, data->d_buf, shdr->sh_size);
782 }
783 }
784
785 if (u->binary->rx_end_markers) {
786 uint32_t *dst = (uint32_t *)(u->rx_ptr + u->binary->rx_end_markers);
787 for (unsigned i = 0; i < DEBUGGER_NUM_MARKERS; ++i)
788 *dst++ = util_cpu_to_le32(DEBUGGER_END_OF_CODE_MARKER);
789 }
790
791 /* Second pass: handle relocations, overwriting uploaded data where
792 * appropriate. */
793 for (unsigned i = 0; i < u->binary->num_parts; ++i) {
794 struct ac_rtld_part *part = &u->binary->parts[i];
795 Elf_Scn *section = NULL;
796 while ((section = elf_nextscn(part->elf, section))) {
797 Elf64_Shdr *shdr = elf64_getshdr(section);
798 if (shdr->sh_type == SHT_REL) {
799 Elf_Data *relocs = elf_getdata(section, NULL);
800 report_elf_if(!relocs || relocs->d_size != shdr->sh_size);
801 if (!apply_relocs(u, i, shdr, relocs))
802 return false;
803 } else if (shdr->sh_type == SHT_RELA) {
804 report_errorf("SHT_RELA not supported");
805 return false;
806 }
807 }
808 }
809
810 return true;
811
812 #undef report_if
813 #undef report_elf_if
814 }
815