xref: /openbmc/linux/tools/perf/util/symbol.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 #define _GNU_SOURCE
2 #include <ctype.h>
3 #include <dirent.h>
4 #include <errno.h>
5 #include <libgen.h>
6 #include <stdlib.h>
7 #include <stdio.h>
8 #include <string.h>
9 #include <sys/types.h>
10 #include <sys/stat.h>
11 #include <sys/param.h>
12 #include <fcntl.h>
13 #include <unistd.h>
14 #include <inttypes.h>
15 #include "build-id.h"
16 #include "debug.h"
17 #include "symbol.h"
18 #include "strlist.h"
19 
20 #include <libelf.h>
21 #include <gelf.h>
22 #include <elf.h>
23 #include <limits.h>
24 #include <sys/utsname.h>
25 
26 #ifndef KSYM_NAME_LEN
27 #define KSYM_NAME_LEN 128
28 #endif
29 
30 #ifndef NT_GNU_BUILD_ID
31 #define NT_GNU_BUILD_ID 3
32 #endif
33 
34 static bool dso__build_id_equal(const struct dso *self, u8 *build_id);
35 static int elf_read_build_id(Elf *elf, void *bf, size_t size);
36 static void dsos__add(struct list_head *head, struct dso *dso);
37 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
38 static int dso__load_kernel_sym(struct dso *self, struct map *map,
39 				symbol_filter_t filter);
40 static int dso__load_guest_kernel_sym(struct dso *self, struct map *map,
41 			symbol_filter_t filter);
42 static int vmlinux_path__nr_entries;
43 static char **vmlinux_path;
44 
45 struct symbol_conf symbol_conf = {
46 	.exclude_other	  = true,
47 	.use_modules	  = true,
48 	.try_vmlinux_path = true,
49 	.symfs            = "",
50 };
51 
52 int dso__name_len(const struct dso *self)
53 {
54 	if (verbose)
55 		return self->long_name_len;
56 
57 	return self->short_name_len;
58 }
59 
60 bool dso__loaded(const struct dso *self, enum map_type type)
61 {
62 	return self->loaded & (1 << type);
63 }
64 
65 bool dso__sorted_by_name(const struct dso *self, enum map_type type)
66 {
67 	return self->sorted_by_name & (1 << type);
68 }
69 
70 static void dso__set_sorted_by_name(struct dso *self, enum map_type type)
71 {
72 	self->sorted_by_name |= (1 << type);
73 }
74 
75 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
76 {
77 	switch (map_type) {
78 	case MAP__FUNCTION:
79 		return symbol_type == 'T' || symbol_type == 'W';
80 	case MAP__VARIABLE:
81 		return symbol_type == 'D' || symbol_type == 'd';
82 	default:
83 		return false;
84 	}
85 }
86 
87 static void symbols__fixup_end(struct rb_root *self)
88 {
89 	struct rb_node *nd, *prevnd = rb_first(self);
90 	struct symbol *curr, *prev;
91 
92 	if (prevnd == NULL)
93 		return;
94 
95 	curr = rb_entry(prevnd, struct symbol, rb_node);
96 
97 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
98 		prev = curr;
99 		curr = rb_entry(nd, struct symbol, rb_node);
100 
101 		if (prev->end == prev->start && prev->end != curr->start)
102 			prev->end = curr->start - 1;
103 	}
104 
105 	/* Last entry */
106 	if (curr->end == curr->start)
107 		curr->end = roundup(curr->start, 4096);
108 }
109 
110 static void __map_groups__fixup_end(struct map_groups *self, enum map_type type)
111 {
112 	struct map *prev, *curr;
113 	struct rb_node *nd, *prevnd = rb_first(&self->maps[type]);
114 
115 	if (prevnd == NULL)
116 		return;
117 
118 	curr = rb_entry(prevnd, struct map, rb_node);
119 
120 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
121 		prev = curr;
122 		curr = rb_entry(nd, struct map, rb_node);
123 		prev->end = curr->start - 1;
124 	}
125 
126 	/*
127 	 * We still haven't the actual symbols, so guess the
128 	 * last map final address.
129 	 */
130 	curr->end = ~0ULL;
131 }
132 
133 static void map_groups__fixup_end(struct map_groups *self)
134 {
135 	int i;
136 	for (i = 0; i < MAP__NR_TYPES; ++i)
137 		__map_groups__fixup_end(self, i);
138 }
139 
140 static struct symbol *symbol__new(u64 start, u64 len, u8 binding,
141 				  const char *name)
142 {
143 	size_t namelen = strlen(name) + 1;
144 	struct symbol *self = calloc(1, (symbol_conf.priv_size +
145 					 sizeof(*self) + namelen));
146 	if (self == NULL)
147 		return NULL;
148 
149 	if (symbol_conf.priv_size)
150 		self = ((void *)self) + symbol_conf.priv_size;
151 
152 	self->start   = start;
153 	self->end     = len ? start + len - 1 : start;
154 	self->binding = binding;
155 	self->namelen = namelen - 1;
156 
157 	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n", __func__, name, start, self->end);
158 
159 	memcpy(self->name, name, namelen);
160 
161 	return self;
162 }
163 
164 void symbol__delete(struct symbol *self)
165 {
166 	free(((void *)self) - symbol_conf.priv_size);
167 }
168 
169 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
170 {
171 	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
172 		       self->start, self->end,
173 		       self->binding == STB_GLOBAL ? 'g' :
174 		       self->binding == STB_LOCAL  ? 'l' : 'w',
175 		       self->name);
176 }
177 
178 void dso__set_long_name(struct dso *self, char *name)
179 {
180 	if (name == NULL)
181 		return;
182 	self->long_name = name;
183 	self->long_name_len = strlen(name);
184 }
185 
186 static void dso__set_short_name(struct dso *self, const char *name)
187 {
188 	if (name == NULL)
189 		return;
190 	self->short_name = name;
191 	self->short_name_len = strlen(name);
192 }
193 
194 static void dso__set_basename(struct dso *self)
195 {
196 	dso__set_short_name(self, basename(self->long_name));
197 }
198 
199 struct dso *dso__new(const char *name)
200 {
201 	struct dso *self = calloc(1, sizeof(*self) + strlen(name) + 1);
202 
203 	if (self != NULL) {
204 		int i;
205 		strcpy(self->name, name);
206 		dso__set_long_name(self, self->name);
207 		dso__set_short_name(self, self->name);
208 		for (i = 0; i < MAP__NR_TYPES; ++i)
209 			self->symbols[i] = self->symbol_names[i] = RB_ROOT;
210 		self->slen_calculated = 0;
211 		self->origin = DSO__ORIG_NOT_FOUND;
212 		self->loaded = 0;
213 		self->sorted_by_name = 0;
214 		self->has_build_id = 0;
215 		self->kernel = DSO_TYPE_USER;
216 		INIT_LIST_HEAD(&self->node);
217 	}
218 
219 	return self;
220 }
221 
222 static void symbols__delete(struct rb_root *self)
223 {
224 	struct symbol *pos;
225 	struct rb_node *next = rb_first(self);
226 
227 	while (next) {
228 		pos = rb_entry(next, struct symbol, rb_node);
229 		next = rb_next(&pos->rb_node);
230 		rb_erase(&pos->rb_node, self);
231 		symbol__delete(pos);
232 	}
233 }
234 
235 void dso__delete(struct dso *self)
236 {
237 	int i;
238 	for (i = 0; i < MAP__NR_TYPES; ++i)
239 		symbols__delete(&self->symbols[i]);
240 	if (self->sname_alloc)
241 		free((char *)self->short_name);
242 	if (self->lname_alloc)
243 		free(self->long_name);
244 	free(self);
245 }
246 
247 void dso__set_build_id(struct dso *self, void *build_id)
248 {
249 	memcpy(self->build_id, build_id, sizeof(self->build_id));
250 	self->has_build_id = 1;
251 }
252 
253 static void symbols__insert(struct rb_root *self, struct symbol *sym)
254 {
255 	struct rb_node **p = &self->rb_node;
256 	struct rb_node *parent = NULL;
257 	const u64 ip = sym->start;
258 	struct symbol *s;
259 
260 	while (*p != NULL) {
261 		parent = *p;
262 		s = rb_entry(parent, struct symbol, rb_node);
263 		if (ip < s->start)
264 			p = &(*p)->rb_left;
265 		else
266 			p = &(*p)->rb_right;
267 	}
268 	rb_link_node(&sym->rb_node, parent, p);
269 	rb_insert_color(&sym->rb_node, self);
270 }
271 
272 static struct symbol *symbols__find(struct rb_root *self, u64 ip)
273 {
274 	struct rb_node *n;
275 
276 	if (self == NULL)
277 		return NULL;
278 
279 	n = self->rb_node;
280 
281 	while (n) {
282 		struct symbol *s = rb_entry(n, struct symbol, rb_node);
283 
284 		if (ip < s->start)
285 			n = n->rb_left;
286 		else if (ip > s->end)
287 			n = n->rb_right;
288 		else
289 			return s;
290 	}
291 
292 	return NULL;
293 }
294 
295 struct symbol_name_rb_node {
296 	struct rb_node	rb_node;
297 	struct symbol	sym;
298 };
299 
300 static void symbols__insert_by_name(struct rb_root *self, struct symbol *sym)
301 {
302 	struct rb_node **p = &self->rb_node;
303 	struct rb_node *parent = NULL;
304 	struct symbol_name_rb_node *symn, *s;
305 
306 	symn = container_of(sym, struct symbol_name_rb_node, sym);
307 
308 	while (*p != NULL) {
309 		parent = *p;
310 		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
311 		if (strcmp(sym->name, s->sym.name) < 0)
312 			p = &(*p)->rb_left;
313 		else
314 			p = &(*p)->rb_right;
315 	}
316 	rb_link_node(&symn->rb_node, parent, p);
317 	rb_insert_color(&symn->rb_node, self);
318 }
319 
320 static void symbols__sort_by_name(struct rb_root *self, struct rb_root *source)
321 {
322 	struct rb_node *nd;
323 
324 	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
325 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
326 		symbols__insert_by_name(self, pos);
327 	}
328 }
329 
330 static struct symbol *symbols__find_by_name(struct rb_root *self, const char *name)
331 {
332 	struct rb_node *n;
333 
334 	if (self == NULL)
335 		return NULL;
336 
337 	n = self->rb_node;
338 
339 	while (n) {
340 		struct symbol_name_rb_node *s;
341 		int cmp;
342 
343 		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
344 		cmp = strcmp(name, s->sym.name);
345 
346 		if (cmp < 0)
347 			n = n->rb_left;
348 		else if (cmp > 0)
349 			n = n->rb_right;
350 		else
351 			return &s->sym;
352 	}
353 
354 	return NULL;
355 }
356 
357 struct symbol *dso__find_symbol(struct dso *self,
358 				enum map_type type, u64 addr)
359 {
360 	return symbols__find(&self->symbols[type], addr);
361 }
362 
363 struct symbol *dso__find_symbol_by_name(struct dso *self, enum map_type type,
364 					const char *name)
365 {
366 	return symbols__find_by_name(&self->symbol_names[type], name);
367 }
368 
369 void dso__sort_by_name(struct dso *self, enum map_type type)
370 {
371 	dso__set_sorted_by_name(self, type);
372 	return symbols__sort_by_name(&self->symbol_names[type],
373 				     &self->symbols[type]);
374 }
375 
376 int build_id__sprintf(const u8 *self, int len, char *bf)
377 {
378 	char *bid = bf;
379 	const u8 *raw = self;
380 	int i;
381 
382 	for (i = 0; i < len; ++i) {
383 		sprintf(bid, "%02x", *raw);
384 		++raw;
385 		bid += 2;
386 	}
387 
388 	return raw - self;
389 }
390 
391 size_t dso__fprintf_buildid(struct dso *self, FILE *fp)
392 {
393 	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
394 
395 	build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
396 	return fprintf(fp, "%s", sbuild_id);
397 }
398 
399 size_t dso__fprintf_symbols_by_name(struct dso *self, enum map_type type, FILE *fp)
400 {
401 	size_t ret = 0;
402 	struct rb_node *nd;
403 	struct symbol_name_rb_node *pos;
404 
405 	for (nd = rb_first(&self->symbol_names[type]); nd; nd = rb_next(nd)) {
406 		pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
407 		fprintf(fp, "%s\n", pos->sym.name);
408 	}
409 
410 	return ret;
411 }
412 
413 size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
414 {
415 	struct rb_node *nd;
416 	size_t ret = fprintf(fp, "dso: %s (", self->short_name);
417 
418 	if (self->short_name != self->long_name)
419 		ret += fprintf(fp, "%s, ", self->long_name);
420 	ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
421 		       self->loaded ? "" : "NOT ");
422 	ret += dso__fprintf_buildid(self, fp);
423 	ret += fprintf(fp, ")\n");
424 	for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
425 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
426 		ret += symbol__fprintf(pos, fp);
427 	}
428 
429 	return ret;
430 }
431 
432 int kallsyms__parse(const char *filename, void *arg,
433 		    int (*process_symbol)(void *arg, const char *name,
434 					  char type, u64 start, u64 end))
435 {
436 	char *line = NULL;
437 	size_t n;
438 	int err = -1;
439 	u64 prev_start = 0;
440 	char prev_symbol_type = 0;
441 	char *prev_symbol_name;
442 	FILE *file = fopen(filename, "r");
443 
444 	if (file == NULL)
445 		goto out_failure;
446 
447 	prev_symbol_name = malloc(KSYM_NAME_LEN);
448 	if (prev_symbol_name == NULL)
449 		goto out_close;
450 
451 	err = 0;
452 
453 	while (!feof(file)) {
454 		u64 start;
455 		int line_len, len;
456 		char symbol_type;
457 		char *symbol_name;
458 
459 		line_len = getline(&line, &n, file);
460 		if (line_len < 0 || !line)
461 			break;
462 
463 		line[--line_len] = '\0'; /* \n */
464 
465 		len = hex2u64(line, &start);
466 
467 		len++;
468 		if (len + 2 >= line_len)
469 			continue;
470 
471 		symbol_type = toupper(line[len]);
472 		len += 2;
473 		symbol_name = line + len;
474 		len = line_len - len;
475 
476 		if (len >= KSYM_NAME_LEN) {
477 			err = -1;
478 			break;
479 		}
480 
481 		if (prev_symbol_type) {
482 			u64 end = start;
483 			if (end != prev_start)
484 				--end;
485 			err = process_symbol(arg, prev_symbol_name,
486 					     prev_symbol_type, prev_start, end);
487 			if (err)
488 				break;
489 		}
490 
491 		memcpy(prev_symbol_name, symbol_name, len + 1);
492 		prev_symbol_type = symbol_type;
493 		prev_start = start;
494 	}
495 
496 	free(prev_symbol_name);
497 	free(line);
498 out_close:
499 	fclose(file);
500 	return err;
501 
502 out_failure:
503 	return -1;
504 }
505 
506 struct process_kallsyms_args {
507 	struct map *map;
508 	struct dso *dso;
509 };
510 
511 static u8 kallsyms2elf_type(char type)
512 {
513 	if (type == 'W')
514 		return STB_WEAK;
515 
516 	return isupper(type) ? STB_GLOBAL : STB_LOCAL;
517 }
518 
519 static int map__process_kallsym_symbol(void *arg, const char *name,
520 				       char type, u64 start, u64 end)
521 {
522 	struct symbol *sym;
523 	struct process_kallsyms_args *a = arg;
524 	struct rb_root *root = &a->dso->symbols[a->map->type];
525 
526 	if (!symbol_type__is_a(type, a->map->type))
527 		return 0;
528 
529 	sym = symbol__new(start, end - start + 1,
530 			  kallsyms2elf_type(type), name);
531 	if (sym == NULL)
532 		return -ENOMEM;
533 	/*
534 	 * We will pass the symbols to the filter later, in
535 	 * map__split_kallsyms, when we have split the maps per module
536 	 */
537 	symbols__insert(root, sym);
538 
539 	return 0;
540 }
541 
542 /*
543  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
544  * so that we can in the next step set the symbol ->end address and then
545  * call kernel_maps__split_kallsyms.
546  */
547 static int dso__load_all_kallsyms(struct dso *self, const char *filename,
548 				  struct map *map)
549 {
550 	struct process_kallsyms_args args = { .map = map, .dso = self, };
551 	return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
552 }
553 
554 /*
555  * Split the symbols into maps, making sure there are no overlaps, i.e. the
556  * kernel range is broken in several maps, named [kernel].N, as we don't have
557  * the original ELF section names vmlinux have.
558  */
559 static int dso__split_kallsyms(struct dso *self, struct map *map,
560 			       symbol_filter_t filter)
561 {
562 	struct map_groups *kmaps = map__kmap(map)->kmaps;
563 	struct machine *machine = kmaps->machine;
564 	struct map *curr_map = map;
565 	struct symbol *pos;
566 	int count = 0, moved = 0;
567 	struct rb_root *root = &self->symbols[map->type];
568 	struct rb_node *next = rb_first(root);
569 	int kernel_range = 0;
570 
571 	while (next) {
572 		char *module;
573 
574 		pos = rb_entry(next, struct symbol, rb_node);
575 		next = rb_next(&pos->rb_node);
576 
577 		module = strchr(pos->name, '\t');
578 		if (module) {
579 			if (!symbol_conf.use_modules)
580 				goto discard_symbol;
581 
582 			*module++ = '\0';
583 
584 			if (strcmp(curr_map->dso->short_name, module)) {
585 				if (curr_map != map &&
586 				    self->kernel == DSO_TYPE_GUEST_KERNEL &&
587 				    machine__is_default_guest(machine)) {
588 					/*
589 					 * We assume all symbols of a module are
590 					 * continuous in * kallsyms, so curr_map
591 					 * points to a module and all its
592 					 * symbols are in its kmap. Mark it as
593 					 * loaded.
594 					 */
595 					dso__set_loaded(curr_map->dso,
596 							curr_map->type);
597 				}
598 
599 				curr_map = map_groups__find_by_name(kmaps,
600 							map->type, module);
601 				if (curr_map == NULL) {
602 					pr_debug("%s/proc/{kallsyms,modules} "
603 					         "inconsistency while looking "
604 						 "for \"%s\" module!\n",
605 						 machine->root_dir, module);
606 					curr_map = map;
607 					goto discard_symbol;
608 				}
609 
610 				if (curr_map->dso->loaded &&
611 				    !machine__is_default_guest(machine))
612 					goto discard_symbol;
613 			}
614 			/*
615 			 * So that we look just like we get from .ko files,
616 			 * i.e. not prelinked, relative to map->start.
617 			 */
618 			pos->start = curr_map->map_ip(curr_map, pos->start);
619 			pos->end   = curr_map->map_ip(curr_map, pos->end);
620 		} else if (curr_map != map) {
621 			char dso_name[PATH_MAX];
622 			struct dso *dso;
623 
624 			if (count == 0) {
625 				curr_map = map;
626 				goto filter_symbol;
627 			}
628 
629 			if (self->kernel == DSO_TYPE_GUEST_KERNEL)
630 				snprintf(dso_name, sizeof(dso_name),
631 					"[guest.kernel].%d",
632 					kernel_range++);
633 			else
634 				snprintf(dso_name, sizeof(dso_name),
635 					"[kernel].%d",
636 					kernel_range++);
637 
638 			dso = dso__new(dso_name);
639 			if (dso == NULL)
640 				return -1;
641 
642 			dso->kernel = self->kernel;
643 
644 			curr_map = map__new2(pos->start, dso, map->type);
645 			if (curr_map == NULL) {
646 				dso__delete(dso);
647 				return -1;
648 			}
649 
650 			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
651 			map_groups__insert(kmaps, curr_map);
652 			++kernel_range;
653 		}
654 filter_symbol:
655 		if (filter && filter(curr_map, pos)) {
656 discard_symbol:		rb_erase(&pos->rb_node, root);
657 			symbol__delete(pos);
658 		} else {
659 			if (curr_map != map) {
660 				rb_erase(&pos->rb_node, root);
661 				symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
662 				++moved;
663 			} else
664 				++count;
665 		}
666 	}
667 
668 	if (curr_map != map &&
669 	    self->kernel == DSO_TYPE_GUEST_KERNEL &&
670 	    machine__is_default_guest(kmaps->machine)) {
671 		dso__set_loaded(curr_map->dso, curr_map->type);
672 	}
673 
674 	return count + moved;
675 }
676 
677 int dso__load_kallsyms(struct dso *self, const char *filename,
678 		       struct map *map, symbol_filter_t filter)
679 {
680 	if (dso__load_all_kallsyms(self, filename, map) < 0)
681 		return -1;
682 
683 	if (self->kernel == DSO_TYPE_GUEST_KERNEL)
684 		self->origin = DSO__ORIG_GUEST_KERNEL;
685 	else
686 		self->origin = DSO__ORIG_KERNEL;
687 
688 	return dso__split_kallsyms(self, map, filter);
689 }
690 
691 static int dso__load_perf_map(struct dso *self, struct map *map,
692 			      symbol_filter_t filter)
693 {
694 	char *line = NULL;
695 	size_t n;
696 	FILE *file;
697 	int nr_syms = 0;
698 
699 	file = fopen(self->long_name, "r");
700 	if (file == NULL)
701 		goto out_failure;
702 
703 	while (!feof(file)) {
704 		u64 start, size;
705 		struct symbol *sym;
706 		int line_len, len;
707 
708 		line_len = getline(&line, &n, file);
709 		if (line_len < 0)
710 			break;
711 
712 		if (!line)
713 			goto out_failure;
714 
715 		line[--line_len] = '\0'; /* \n */
716 
717 		len = hex2u64(line, &start);
718 
719 		len++;
720 		if (len + 2 >= line_len)
721 			continue;
722 
723 		len += hex2u64(line + len, &size);
724 
725 		len++;
726 		if (len + 2 >= line_len)
727 			continue;
728 
729 		sym = symbol__new(start, size, STB_GLOBAL, line + len);
730 
731 		if (sym == NULL)
732 			goto out_delete_line;
733 
734 		if (filter && filter(map, sym))
735 			symbol__delete(sym);
736 		else {
737 			symbols__insert(&self->symbols[map->type], sym);
738 			nr_syms++;
739 		}
740 	}
741 
742 	free(line);
743 	fclose(file);
744 
745 	return nr_syms;
746 
747 out_delete_line:
748 	free(line);
749 out_failure:
750 	return -1;
751 }
752 
753 /**
754  * elf_symtab__for_each_symbol - iterate thru all the symbols
755  *
756  * @self: struct elf_symtab instance to iterate
757  * @idx: uint32_t idx
758  * @sym: GElf_Sym iterator
759  */
760 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
761 	for (idx = 0, gelf_getsym(syms, idx, &sym);\
762 	     idx < nr_syms; \
763 	     idx++, gelf_getsym(syms, idx, &sym))
764 
765 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
766 {
767 	return GELF_ST_TYPE(sym->st_info);
768 }
769 
770 static inline int elf_sym__is_function(const GElf_Sym *sym)
771 {
772 	return elf_sym__type(sym) == STT_FUNC &&
773 	       sym->st_name != 0 &&
774 	       sym->st_shndx != SHN_UNDEF;
775 }
776 
777 static inline bool elf_sym__is_object(const GElf_Sym *sym)
778 {
779 	return elf_sym__type(sym) == STT_OBJECT &&
780 		sym->st_name != 0 &&
781 		sym->st_shndx != SHN_UNDEF;
782 }
783 
784 static inline int elf_sym__is_label(const GElf_Sym *sym)
785 {
786 	return elf_sym__type(sym) == STT_NOTYPE &&
787 		sym->st_name != 0 &&
788 		sym->st_shndx != SHN_UNDEF &&
789 		sym->st_shndx != SHN_ABS;
790 }
791 
792 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
793 					const Elf_Data *secstrs)
794 {
795 	return secstrs->d_buf + shdr->sh_name;
796 }
797 
798 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
799 					const Elf_Data *secstrs)
800 {
801 	return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
802 }
803 
804 static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
805 				    const Elf_Data *secstrs)
806 {
807 	return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
808 }
809 
810 static inline const char *elf_sym__name(const GElf_Sym *sym,
811 					const Elf_Data *symstrs)
812 {
813 	return symstrs->d_buf + sym->st_name;
814 }
815 
816 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
817 				    GElf_Shdr *shp, const char *name,
818 				    size_t *idx)
819 {
820 	Elf_Scn *sec = NULL;
821 	size_t cnt = 1;
822 
823 	while ((sec = elf_nextscn(elf, sec)) != NULL) {
824 		char *str;
825 
826 		gelf_getshdr(sec, shp);
827 		str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
828 		if (!strcmp(name, str)) {
829 			if (idx)
830 				*idx = cnt;
831 			break;
832 		}
833 		++cnt;
834 	}
835 
836 	return sec;
837 }
838 
839 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
840 	for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
841 	     idx < nr_entries; \
842 	     ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
843 
844 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
845 	for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
846 	     idx < nr_entries; \
847 	     ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
848 
849 /*
850  * We need to check if we have a .dynsym, so that we can handle the
851  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
852  * .dynsym or .symtab).
853  * And always look at the original dso, not at debuginfo packages, that
854  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
855  */
856 static int dso__synthesize_plt_symbols(struct  dso *self, struct map *map,
857 				       symbol_filter_t filter)
858 {
859 	uint32_t nr_rel_entries, idx;
860 	GElf_Sym sym;
861 	u64 plt_offset;
862 	GElf_Shdr shdr_plt;
863 	struct symbol *f;
864 	GElf_Shdr shdr_rel_plt, shdr_dynsym;
865 	Elf_Data *reldata, *syms, *symstrs;
866 	Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
867 	size_t dynsym_idx;
868 	GElf_Ehdr ehdr;
869 	char sympltname[1024];
870 	Elf *elf;
871 	int nr = 0, symidx, fd, err = 0;
872 	char name[PATH_MAX];
873 
874 	snprintf(name, sizeof(name), "%s%s",
875 		 symbol_conf.symfs, self->long_name);
876 	fd = open(name, O_RDONLY);
877 	if (fd < 0)
878 		goto out;
879 
880 	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
881 	if (elf == NULL)
882 		goto out_close;
883 
884 	if (gelf_getehdr(elf, &ehdr) == NULL)
885 		goto out_elf_end;
886 
887 	scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
888 					 ".dynsym", &dynsym_idx);
889 	if (scn_dynsym == NULL)
890 		goto out_elf_end;
891 
892 	scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
893 					  ".rela.plt", NULL);
894 	if (scn_plt_rel == NULL) {
895 		scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
896 						  ".rel.plt", NULL);
897 		if (scn_plt_rel == NULL)
898 			goto out_elf_end;
899 	}
900 
901 	err = -1;
902 
903 	if (shdr_rel_plt.sh_link != dynsym_idx)
904 		goto out_elf_end;
905 
906 	if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
907 		goto out_elf_end;
908 
909 	/*
910 	 * Fetch the relocation section to find the idxes to the GOT
911 	 * and the symbols in the .dynsym they refer to.
912 	 */
913 	reldata = elf_getdata(scn_plt_rel, NULL);
914 	if (reldata == NULL)
915 		goto out_elf_end;
916 
917 	syms = elf_getdata(scn_dynsym, NULL);
918 	if (syms == NULL)
919 		goto out_elf_end;
920 
921 	scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
922 	if (scn_symstrs == NULL)
923 		goto out_elf_end;
924 
925 	symstrs = elf_getdata(scn_symstrs, NULL);
926 	if (symstrs == NULL)
927 		goto out_elf_end;
928 
929 	nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
930 	plt_offset = shdr_plt.sh_offset;
931 
932 	if (shdr_rel_plt.sh_type == SHT_RELA) {
933 		GElf_Rela pos_mem, *pos;
934 
935 		elf_section__for_each_rela(reldata, pos, pos_mem, idx,
936 					   nr_rel_entries) {
937 			symidx = GELF_R_SYM(pos->r_info);
938 			plt_offset += shdr_plt.sh_entsize;
939 			gelf_getsym(syms, symidx, &sym);
940 			snprintf(sympltname, sizeof(sympltname),
941 				 "%s@plt", elf_sym__name(&sym, symstrs));
942 
943 			f = symbol__new(plt_offset, shdr_plt.sh_entsize,
944 					STB_GLOBAL, sympltname);
945 			if (!f)
946 				goto out_elf_end;
947 
948 			if (filter && filter(map, f))
949 				symbol__delete(f);
950 			else {
951 				symbols__insert(&self->symbols[map->type], f);
952 				++nr;
953 			}
954 		}
955 	} else if (shdr_rel_plt.sh_type == SHT_REL) {
956 		GElf_Rel pos_mem, *pos;
957 		elf_section__for_each_rel(reldata, pos, pos_mem, idx,
958 					  nr_rel_entries) {
959 			symidx = GELF_R_SYM(pos->r_info);
960 			plt_offset += shdr_plt.sh_entsize;
961 			gelf_getsym(syms, symidx, &sym);
962 			snprintf(sympltname, sizeof(sympltname),
963 				 "%s@plt", elf_sym__name(&sym, symstrs));
964 
965 			f = symbol__new(plt_offset, shdr_plt.sh_entsize,
966 					STB_GLOBAL, sympltname);
967 			if (!f)
968 				goto out_elf_end;
969 
970 			if (filter && filter(map, f))
971 				symbol__delete(f);
972 			else {
973 				symbols__insert(&self->symbols[map->type], f);
974 				++nr;
975 			}
976 		}
977 	}
978 
979 	err = 0;
980 out_elf_end:
981 	elf_end(elf);
982 out_close:
983 	close(fd);
984 
985 	if (err == 0)
986 		return nr;
987 out:
988 	pr_debug("%s: problems reading %s PLT info.\n",
989 		 __func__, self->long_name);
990 	return 0;
991 }
992 
993 static bool elf_sym__is_a(GElf_Sym *self, enum map_type type)
994 {
995 	switch (type) {
996 	case MAP__FUNCTION:
997 		return elf_sym__is_function(self);
998 	case MAP__VARIABLE:
999 		return elf_sym__is_object(self);
1000 	default:
1001 		return false;
1002 	}
1003 }
1004 
1005 static bool elf_sec__is_a(GElf_Shdr *self, Elf_Data *secstrs, enum map_type type)
1006 {
1007 	switch (type) {
1008 	case MAP__FUNCTION:
1009 		return elf_sec__is_text(self, secstrs);
1010 	case MAP__VARIABLE:
1011 		return elf_sec__is_data(self, secstrs);
1012 	default:
1013 		return false;
1014 	}
1015 }
1016 
1017 static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
1018 {
1019 	Elf_Scn *sec = NULL;
1020 	GElf_Shdr shdr;
1021 	size_t cnt = 1;
1022 
1023 	while ((sec = elf_nextscn(elf, sec)) != NULL) {
1024 		gelf_getshdr(sec, &shdr);
1025 
1026 		if ((addr >= shdr.sh_addr) &&
1027 		    (addr < (shdr.sh_addr + shdr.sh_size)))
1028 			return cnt;
1029 
1030 		++cnt;
1031 	}
1032 
1033 	return -1;
1034 }
1035 
1036 static int dso__load_sym(struct dso *self, struct map *map, const char *name,
1037 			 int fd, symbol_filter_t filter, int kmodule,
1038 			 int want_symtab)
1039 {
1040 	struct kmap *kmap = self->kernel ? map__kmap(map) : NULL;
1041 	struct map *curr_map = map;
1042 	struct dso *curr_dso = self;
1043 	Elf_Data *symstrs, *secstrs;
1044 	uint32_t nr_syms;
1045 	int err = -1;
1046 	uint32_t idx;
1047 	GElf_Ehdr ehdr;
1048 	GElf_Shdr shdr, opdshdr;
1049 	Elf_Data *syms, *opddata = NULL;
1050 	GElf_Sym sym;
1051 	Elf_Scn *sec, *sec_strndx, *opdsec;
1052 	Elf *elf;
1053 	int nr = 0;
1054 	size_t opdidx = 0;
1055 
1056 	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1057 	if (elf == NULL) {
1058 		pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
1059 		goto out_close;
1060 	}
1061 
1062 	if (gelf_getehdr(elf, &ehdr) == NULL) {
1063 		pr_debug("%s: cannot get elf header.\n", __func__);
1064 		goto out_elf_end;
1065 	}
1066 
1067 	/* Always reject images with a mismatched build-id: */
1068 	if (self->has_build_id) {
1069 		u8 build_id[BUILD_ID_SIZE];
1070 
1071 		if (elf_read_build_id(elf, build_id,
1072 				      BUILD_ID_SIZE) != BUILD_ID_SIZE)
1073 			goto out_elf_end;
1074 
1075 		if (!dso__build_id_equal(self, build_id))
1076 			goto out_elf_end;
1077 	}
1078 
1079 	sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
1080 	if (sec == NULL) {
1081 		if (want_symtab)
1082 			goto out_elf_end;
1083 
1084 		sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
1085 		if (sec == NULL)
1086 			goto out_elf_end;
1087 	}
1088 
1089 	opdsec = elf_section_by_name(elf, &ehdr, &opdshdr, ".opd", &opdidx);
1090 	if (opdsec)
1091 		opddata = elf_rawdata(opdsec, NULL);
1092 
1093 	syms = elf_getdata(sec, NULL);
1094 	if (syms == NULL)
1095 		goto out_elf_end;
1096 
1097 	sec = elf_getscn(elf, shdr.sh_link);
1098 	if (sec == NULL)
1099 		goto out_elf_end;
1100 
1101 	symstrs = elf_getdata(sec, NULL);
1102 	if (symstrs == NULL)
1103 		goto out_elf_end;
1104 
1105 	sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
1106 	if (sec_strndx == NULL)
1107 		goto out_elf_end;
1108 
1109 	secstrs = elf_getdata(sec_strndx, NULL);
1110 	if (secstrs == NULL)
1111 		goto out_elf_end;
1112 
1113 	nr_syms = shdr.sh_size / shdr.sh_entsize;
1114 
1115 	memset(&sym, 0, sizeof(sym));
1116 	if (self->kernel == DSO_TYPE_USER) {
1117 		self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
1118 				elf_section_by_name(elf, &ehdr, &shdr,
1119 						     ".gnu.prelink_undo",
1120 						     NULL) != NULL);
1121 	} else self->adjust_symbols = 0;
1122 
1123 	elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
1124 		struct symbol *f;
1125 		const char *elf_name = elf_sym__name(&sym, symstrs);
1126 		char *demangled = NULL;
1127 		int is_label = elf_sym__is_label(&sym);
1128 		const char *section_name;
1129 
1130 		if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
1131 		    strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
1132 			kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
1133 
1134 		if (!is_label && !elf_sym__is_a(&sym, map->type))
1135 			continue;
1136 
1137 		/* Reject ARM ELF "mapping symbols": these aren't unique and
1138 		 * don't identify functions, so will confuse the profile
1139 		 * output: */
1140 		if (ehdr.e_machine == EM_ARM) {
1141 			if (!strcmp(elf_name, "$a") ||
1142 			    !strcmp(elf_name, "$d") ||
1143 			    !strcmp(elf_name, "$t"))
1144 				continue;
1145 		}
1146 
1147 		if (opdsec && sym.st_shndx == opdidx) {
1148 			u32 offset = sym.st_value - opdshdr.sh_addr;
1149 			u64 *opd = opddata->d_buf + offset;
1150 			sym.st_value = *opd;
1151 			sym.st_shndx = elf_addr_to_index(elf, sym.st_value);
1152 		}
1153 
1154 		sec = elf_getscn(elf, sym.st_shndx);
1155 		if (!sec)
1156 			goto out_elf_end;
1157 
1158 		gelf_getshdr(sec, &shdr);
1159 
1160 		if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
1161 			continue;
1162 
1163 		section_name = elf_sec__name(&shdr, secstrs);
1164 
1165 		/* On ARM, symbols for thumb functions have 1 added to
1166 		 * the symbol address as a flag - remove it */
1167 		if ((ehdr.e_machine == EM_ARM) &&
1168 		    (map->type == MAP__FUNCTION) &&
1169 		    (sym.st_value & 1))
1170 			--sym.st_value;
1171 
1172 		if (self->kernel != DSO_TYPE_USER || kmodule) {
1173 			char dso_name[PATH_MAX];
1174 
1175 			if (strcmp(section_name,
1176 				   (curr_dso->short_name +
1177 				    self->short_name_len)) == 0)
1178 				goto new_symbol;
1179 
1180 			if (strcmp(section_name, ".text") == 0) {
1181 				curr_map = map;
1182 				curr_dso = self;
1183 				goto new_symbol;
1184 			}
1185 
1186 			snprintf(dso_name, sizeof(dso_name),
1187 				 "%s%s", self->short_name, section_name);
1188 
1189 			curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name);
1190 			if (curr_map == NULL) {
1191 				u64 start = sym.st_value;
1192 
1193 				if (kmodule)
1194 					start += map->start + shdr.sh_offset;
1195 
1196 				curr_dso = dso__new(dso_name);
1197 				if (curr_dso == NULL)
1198 					goto out_elf_end;
1199 				curr_dso->kernel = self->kernel;
1200 				curr_map = map__new2(start, curr_dso,
1201 						     map->type);
1202 				if (curr_map == NULL) {
1203 					dso__delete(curr_dso);
1204 					goto out_elf_end;
1205 				}
1206 				curr_map->map_ip = identity__map_ip;
1207 				curr_map->unmap_ip = identity__map_ip;
1208 				curr_dso->origin = self->origin;
1209 				map_groups__insert(kmap->kmaps, curr_map);
1210 				dsos__add(&self->node, curr_dso);
1211 				dso__set_loaded(curr_dso, map->type);
1212 			} else
1213 				curr_dso = curr_map->dso;
1214 
1215 			goto new_symbol;
1216 		}
1217 
1218 		if (curr_dso->adjust_symbols) {
1219 			pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " "
1220 				  "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__,
1221 				  (u64)sym.st_value, (u64)shdr.sh_addr,
1222 				  (u64)shdr.sh_offset);
1223 			sym.st_value -= shdr.sh_addr - shdr.sh_offset;
1224 		}
1225 		/*
1226 		 * We need to figure out if the object was created from C++ sources
1227 		 * DWARF DW_compile_unit has this, but we don't always have access
1228 		 * to it...
1229 		 */
1230 		demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
1231 		if (demangled != NULL)
1232 			elf_name = demangled;
1233 new_symbol:
1234 		f = symbol__new(sym.st_value, sym.st_size,
1235 				GELF_ST_BIND(sym.st_info), elf_name);
1236 		free(demangled);
1237 		if (!f)
1238 			goto out_elf_end;
1239 
1240 		if (filter && filter(curr_map, f))
1241 			symbol__delete(f);
1242 		else {
1243 			symbols__insert(&curr_dso->symbols[curr_map->type], f);
1244 			nr++;
1245 		}
1246 	}
1247 
1248 	/*
1249 	 * For misannotated, zeroed, ASM function sizes.
1250 	 */
1251 	if (nr > 0) {
1252 		symbols__fixup_end(&self->symbols[map->type]);
1253 		if (kmap) {
1254 			/*
1255 			 * We need to fixup this here too because we create new
1256 			 * maps here, for things like vsyscall sections.
1257 			 */
1258 			__map_groups__fixup_end(kmap->kmaps, map->type);
1259 		}
1260 	}
1261 	err = nr;
1262 out_elf_end:
1263 	elf_end(elf);
1264 out_close:
1265 	return err;
1266 }
1267 
1268 static bool dso__build_id_equal(const struct dso *self, u8 *build_id)
1269 {
1270 	return memcmp(self->build_id, build_id, sizeof(self->build_id)) == 0;
1271 }
1272 
1273 bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
1274 {
1275 	bool have_build_id = false;
1276 	struct dso *pos;
1277 
1278 	list_for_each_entry(pos, head, node) {
1279 		if (with_hits && !pos->hit)
1280 			continue;
1281 		if (pos->has_build_id) {
1282 			have_build_id = true;
1283 			continue;
1284 		}
1285 		if (filename__read_build_id(pos->long_name, pos->build_id,
1286 					    sizeof(pos->build_id)) > 0) {
1287 			have_build_id	  = true;
1288 			pos->has_build_id = true;
1289 		}
1290 	}
1291 
1292 	return have_build_id;
1293 }
1294 
1295 /*
1296  * Align offset to 4 bytes as needed for note name and descriptor data.
1297  */
1298 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
1299 
1300 static int elf_read_build_id(Elf *elf, void *bf, size_t size)
1301 {
1302 	int err = -1;
1303 	GElf_Ehdr ehdr;
1304 	GElf_Shdr shdr;
1305 	Elf_Data *data;
1306 	Elf_Scn *sec;
1307 	Elf_Kind ek;
1308 	void *ptr;
1309 
1310 	if (size < BUILD_ID_SIZE)
1311 		goto out;
1312 
1313 	ek = elf_kind(elf);
1314 	if (ek != ELF_K_ELF)
1315 		goto out;
1316 
1317 	if (gelf_getehdr(elf, &ehdr) == NULL) {
1318 		pr_err("%s: cannot get elf header.\n", __func__);
1319 		goto out;
1320 	}
1321 
1322 	sec = elf_section_by_name(elf, &ehdr, &shdr,
1323 				  ".note.gnu.build-id", NULL);
1324 	if (sec == NULL) {
1325 		sec = elf_section_by_name(elf, &ehdr, &shdr,
1326 					  ".notes", NULL);
1327 		if (sec == NULL)
1328 			goto out;
1329 	}
1330 
1331 	data = elf_getdata(sec, NULL);
1332 	if (data == NULL)
1333 		goto out;
1334 
1335 	ptr = data->d_buf;
1336 	while (ptr < (data->d_buf + data->d_size)) {
1337 		GElf_Nhdr *nhdr = ptr;
1338 		int namesz = NOTE_ALIGN(nhdr->n_namesz),
1339 		    descsz = NOTE_ALIGN(nhdr->n_descsz);
1340 		const char *name;
1341 
1342 		ptr += sizeof(*nhdr);
1343 		name = ptr;
1344 		ptr += namesz;
1345 		if (nhdr->n_type == NT_GNU_BUILD_ID &&
1346 		    nhdr->n_namesz == sizeof("GNU")) {
1347 			if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
1348 				memcpy(bf, ptr, BUILD_ID_SIZE);
1349 				err = BUILD_ID_SIZE;
1350 				break;
1351 			}
1352 		}
1353 		ptr += descsz;
1354 	}
1355 
1356 out:
1357 	return err;
1358 }
1359 
1360 int filename__read_build_id(const char *filename, void *bf, size_t size)
1361 {
1362 	int fd, err = -1;
1363 	Elf *elf;
1364 
1365 	if (size < BUILD_ID_SIZE)
1366 		goto out;
1367 
1368 	fd = open(filename, O_RDONLY);
1369 	if (fd < 0)
1370 		goto out;
1371 
1372 	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1373 	if (elf == NULL) {
1374 		pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
1375 		goto out_close;
1376 	}
1377 
1378 	err = elf_read_build_id(elf, bf, size);
1379 
1380 	elf_end(elf);
1381 out_close:
1382 	close(fd);
1383 out:
1384 	return err;
1385 }
1386 
1387 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
1388 {
1389 	int fd, err = -1;
1390 
1391 	if (size < BUILD_ID_SIZE)
1392 		goto out;
1393 
1394 	fd = open(filename, O_RDONLY);
1395 	if (fd < 0)
1396 		goto out;
1397 
1398 	while (1) {
1399 		char bf[BUFSIZ];
1400 		GElf_Nhdr nhdr;
1401 		int namesz, descsz;
1402 
1403 		if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
1404 			break;
1405 
1406 		namesz = NOTE_ALIGN(nhdr.n_namesz);
1407 		descsz = NOTE_ALIGN(nhdr.n_descsz);
1408 		if (nhdr.n_type == NT_GNU_BUILD_ID &&
1409 		    nhdr.n_namesz == sizeof("GNU")) {
1410 			if (read(fd, bf, namesz) != namesz)
1411 				break;
1412 			if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
1413 				if (read(fd, build_id,
1414 				    BUILD_ID_SIZE) == BUILD_ID_SIZE) {
1415 					err = 0;
1416 					break;
1417 				}
1418 			} else if (read(fd, bf, descsz) != descsz)
1419 				break;
1420 		} else {
1421 			int n = namesz + descsz;
1422 			if (read(fd, bf, n) != n)
1423 				break;
1424 		}
1425 	}
1426 	close(fd);
1427 out:
1428 	return err;
1429 }
1430 
1431 char dso__symtab_origin(const struct dso *self)
1432 {
1433 	static const char origin[] = {
1434 		[DSO__ORIG_KERNEL] =   'k',
1435 		[DSO__ORIG_JAVA_JIT] = 'j',
1436 		[DSO__ORIG_BUILD_ID_CACHE] = 'B',
1437 		[DSO__ORIG_FEDORA] =   'f',
1438 		[DSO__ORIG_UBUNTU] =   'u',
1439 		[DSO__ORIG_BUILDID] =  'b',
1440 		[DSO__ORIG_DSO] =      'd',
1441 		[DSO__ORIG_KMODULE] =  'K',
1442 		[DSO__ORIG_GUEST_KERNEL] =  'g',
1443 		[DSO__ORIG_GUEST_KMODULE] =  'G',
1444 	};
1445 
1446 	if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
1447 		return '!';
1448 	return origin[self->origin];
1449 }
1450 
1451 int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
1452 {
1453 	int size = PATH_MAX;
1454 	char *name;
1455 	int ret = -1;
1456 	int fd;
1457 	struct machine *machine;
1458 	const char *root_dir;
1459 	int want_symtab;
1460 
1461 	dso__set_loaded(self, map->type);
1462 
1463 	if (self->kernel == DSO_TYPE_KERNEL)
1464 		return dso__load_kernel_sym(self, map, filter);
1465 	else if (self->kernel == DSO_TYPE_GUEST_KERNEL)
1466 		return dso__load_guest_kernel_sym(self, map, filter);
1467 
1468 	if (map->groups && map->groups->machine)
1469 		machine = map->groups->machine;
1470 	else
1471 		machine = NULL;
1472 
1473 	name = malloc(size);
1474 	if (!name)
1475 		return -1;
1476 
1477 	self->adjust_symbols = 0;
1478 
1479 	if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
1480 		ret = dso__load_perf_map(self, map, filter);
1481 		self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
1482 					 DSO__ORIG_NOT_FOUND;
1483 		return ret;
1484 	}
1485 
1486 	/* Iterate over candidate debug images.
1487 	 * On the first pass, only load images if they have a full symtab.
1488 	 * Failing that, do a second pass where we accept .dynsym also
1489 	 */
1490 	for (self->origin = DSO__ORIG_BUILD_ID_CACHE, want_symtab = 1;
1491 	     self->origin != DSO__ORIG_NOT_FOUND;
1492 	     self->origin++) {
1493 		switch (self->origin) {
1494 		case DSO__ORIG_BUILD_ID_CACHE:
1495 			/* skip the locally configured cache if a symfs is given */
1496 			if (symbol_conf.symfs[0] ||
1497 			    (dso__build_id_filename(self, name, size) == NULL)) {
1498 				continue;
1499 			}
1500 			break;
1501 		case DSO__ORIG_FEDORA:
1502 			snprintf(name, size, "%s/usr/lib/debug%s.debug",
1503 				 symbol_conf.symfs, self->long_name);
1504 			break;
1505 		case DSO__ORIG_UBUNTU:
1506 			snprintf(name, size, "%s/usr/lib/debug%s",
1507 				 symbol_conf.symfs, self->long_name);
1508 			break;
1509 		case DSO__ORIG_BUILDID: {
1510 			char build_id_hex[BUILD_ID_SIZE * 2 + 1];
1511 
1512 			if (!self->has_build_id)
1513 				continue;
1514 
1515 			build_id__sprintf(self->build_id,
1516 					  sizeof(self->build_id),
1517 					  build_id_hex);
1518 			snprintf(name, size,
1519 				 "%s/usr/lib/debug/.build-id/%.2s/%s.debug",
1520 				 symbol_conf.symfs, build_id_hex, build_id_hex + 2);
1521 			}
1522 			break;
1523 		case DSO__ORIG_DSO:
1524 			snprintf(name, size, "%s%s",
1525 			     symbol_conf.symfs, self->long_name);
1526 			break;
1527 		case DSO__ORIG_GUEST_KMODULE:
1528 			if (map->groups && map->groups->machine)
1529 				root_dir = map->groups->machine->root_dir;
1530 			else
1531 				root_dir = "";
1532 			snprintf(name, size, "%s%s%s", symbol_conf.symfs,
1533 				 root_dir, self->long_name);
1534 			break;
1535 
1536 		case DSO__ORIG_KMODULE:
1537 			snprintf(name, size, "%s%s", symbol_conf.symfs,
1538 				 self->long_name);
1539 			break;
1540 
1541 		default:
1542 			/*
1543 			 * If we wanted a full symtab but no image had one,
1544 			 * relax our requirements and repeat the search.
1545 			 */
1546 			if (want_symtab) {
1547 				want_symtab = 0;
1548 				self->origin = DSO__ORIG_BUILD_ID_CACHE;
1549 			} else
1550 				continue;
1551 		}
1552 
1553 		/* Name is now the name of the next image to try */
1554 		fd = open(name, O_RDONLY);
1555 		if (fd < 0)
1556 			continue;
1557 
1558 		ret = dso__load_sym(self, map, name, fd, filter, 0,
1559 				    want_symtab);
1560 		close(fd);
1561 
1562 		/*
1563 		 * Some people seem to have debuginfo files _WITHOUT_ debug
1564 		 * info!?!?
1565 		 */
1566 		if (!ret)
1567 			continue;
1568 
1569 		if (ret > 0) {
1570 			int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
1571 			if (nr_plt > 0)
1572 				ret += nr_plt;
1573 			break;
1574 		}
1575 	}
1576 
1577 	free(name);
1578 	if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
1579 		return 0;
1580 	return ret;
1581 }
1582 
1583 struct map *map_groups__find_by_name(struct map_groups *self,
1584 				     enum map_type type, const char *name)
1585 {
1586 	struct rb_node *nd;
1587 
1588 	for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
1589 		struct map *map = rb_entry(nd, struct map, rb_node);
1590 
1591 		if (map->dso && strcmp(map->dso->short_name, name) == 0)
1592 			return map;
1593 	}
1594 
1595 	return NULL;
1596 }
1597 
1598 static int dso__kernel_module_get_build_id(struct dso *self,
1599 				const char *root_dir)
1600 {
1601 	char filename[PATH_MAX];
1602 	/*
1603 	 * kernel module short names are of the form "[module]" and
1604 	 * we need just "module" here.
1605 	 */
1606 	const char *name = self->short_name + 1;
1607 
1608 	snprintf(filename, sizeof(filename),
1609 		 "%s/sys/module/%.*s/notes/.note.gnu.build-id",
1610 		 root_dir, (int)strlen(name) - 1, name);
1611 
1612 	if (sysfs__read_build_id(filename, self->build_id,
1613 				 sizeof(self->build_id)) == 0)
1614 		self->has_build_id = true;
1615 
1616 	return 0;
1617 }
1618 
1619 static int map_groups__set_modules_path_dir(struct map_groups *self,
1620 				const char *dir_name)
1621 {
1622 	struct dirent *dent;
1623 	DIR *dir = opendir(dir_name);
1624 	int ret = 0;
1625 
1626 	if (!dir) {
1627 		pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
1628 		return -1;
1629 	}
1630 
1631 	while ((dent = readdir(dir)) != NULL) {
1632 		char path[PATH_MAX];
1633 		struct stat st;
1634 
1635 		/*sshfs might return bad dent->d_type, so we have to stat*/
1636 		sprintf(path, "%s/%s", dir_name, dent->d_name);
1637 		if (stat(path, &st))
1638 			continue;
1639 
1640 		if (S_ISDIR(st.st_mode)) {
1641 			if (!strcmp(dent->d_name, ".") ||
1642 			    !strcmp(dent->d_name, ".."))
1643 				continue;
1644 
1645 			snprintf(path, sizeof(path), "%s/%s",
1646 				 dir_name, dent->d_name);
1647 			ret = map_groups__set_modules_path_dir(self, path);
1648 			if (ret < 0)
1649 				goto out;
1650 		} else {
1651 			char *dot = strrchr(dent->d_name, '.'),
1652 			     dso_name[PATH_MAX];
1653 			struct map *map;
1654 			char *long_name;
1655 
1656 			if (dot == NULL || strcmp(dot, ".ko"))
1657 				continue;
1658 			snprintf(dso_name, sizeof(dso_name), "[%.*s]",
1659 				 (int)(dot - dent->d_name), dent->d_name);
1660 
1661 			strxfrchar(dso_name, '-', '_');
1662 			map = map_groups__find_by_name(self, MAP__FUNCTION, dso_name);
1663 			if (map == NULL)
1664 				continue;
1665 
1666 			snprintf(path, sizeof(path), "%s/%s",
1667 				 dir_name, dent->d_name);
1668 
1669 			long_name = strdup(path);
1670 			if (long_name == NULL) {
1671 				ret = -1;
1672 				goto out;
1673 			}
1674 			dso__set_long_name(map->dso, long_name);
1675 			map->dso->lname_alloc = 1;
1676 			dso__kernel_module_get_build_id(map->dso, "");
1677 		}
1678 	}
1679 
1680 out:
1681 	closedir(dir);
1682 	return ret;
1683 }
1684 
1685 static char *get_kernel_version(const char *root_dir)
1686 {
1687 	char version[PATH_MAX];
1688 	FILE *file;
1689 	char *name, *tmp;
1690 	const char *prefix = "Linux version ";
1691 
1692 	sprintf(version, "%s/proc/version", root_dir);
1693 	file = fopen(version, "r");
1694 	if (!file)
1695 		return NULL;
1696 
1697 	version[0] = '\0';
1698 	tmp = fgets(version, sizeof(version), file);
1699 	fclose(file);
1700 
1701 	name = strstr(version, prefix);
1702 	if (!name)
1703 		return NULL;
1704 	name += strlen(prefix);
1705 	tmp = strchr(name, ' ');
1706 	if (tmp)
1707 		*tmp = '\0';
1708 
1709 	return strdup(name);
1710 }
1711 
1712 static int machine__set_modules_path(struct machine *self)
1713 {
1714 	char *version;
1715 	char modules_path[PATH_MAX];
1716 
1717 	version = get_kernel_version(self->root_dir);
1718 	if (!version)
1719 		return -1;
1720 
1721 	snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s/kernel",
1722 		 self->root_dir, version);
1723 	free(version);
1724 
1725 	return map_groups__set_modules_path_dir(&self->kmaps, modules_path);
1726 }
1727 
1728 /*
1729  * Constructor variant for modules (where we know from /proc/modules where
1730  * they are loaded) and for vmlinux, where only after we load all the
1731  * symbols we'll know where it starts and ends.
1732  */
1733 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
1734 {
1735 	struct map *self = calloc(1, (sizeof(*self) +
1736 				      (dso->kernel ? sizeof(struct kmap) : 0)));
1737 	if (self != NULL) {
1738 		/*
1739 		 * ->end will be filled after we load all the symbols
1740 		 */
1741 		map__init(self, type, start, 0, 0, dso);
1742 	}
1743 
1744 	return self;
1745 }
1746 
1747 struct map *machine__new_module(struct machine *self, u64 start,
1748 				const char *filename)
1749 {
1750 	struct map *map;
1751 	struct dso *dso = __dsos__findnew(&self->kernel_dsos, filename);
1752 
1753 	if (dso == NULL)
1754 		return NULL;
1755 
1756 	map = map__new2(start, dso, MAP__FUNCTION);
1757 	if (map == NULL)
1758 		return NULL;
1759 
1760 	if (machine__is_host(self))
1761 		dso->origin = DSO__ORIG_KMODULE;
1762 	else
1763 		dso->origin = DSO__ORIG_GUEST_KMODULE;
1764 	map_groups__insert(&self->kmaps, map);
1765 	return map;
1766 }
1767 
1768 static int machine__create_modules(struct machine *self)
1769 {
1770 	char *line = NULL;
1771 	size_t n;
1772 	FILE *file;
1773 	struct map *map;
1774 	const char *modules;
1775 	char path[PATH_MAX];
1776 
1777 	if (machine__is_default_guest(self))
1778 		modules = symbol_conf.default_guest_modules;
1779 	else {
1780 		sprintf(path, "%s/proc/modules", self->root_dir);
1781 		modules = path;
1782 	}
1783 
1784 	file = fopen(modules, "r");
1785 	if (file == NULL)
1786 		return -1;
1787 
1788 	while (!feof(file)) {
1789 		char name[PATH_MAX];
1790 		u64 start;
1791 		char *sep;
1792 		int line_len;
1793 
1794 		line_len = getline(&line, &n, file);
1795 		if (line_len < 0)
1796 			break;
1797 
1798 		if (!line)
1799 			goto out_failure;
1800 
1801 		line[--line_len] = '\0'; /* \n */
1802 
1803 		sep = strrchr(line, 'x');
1804 		if (sep == NULL)
1805 			continue;
1806 
1807 		hex2u64(sep + 1, &start);
1808 
1809 		sep = strchr(line, ' ');
1810 		if (sep == NULL)
1811 			continue;
1812 
1813 		*sep = '\0';
1814 
1815 		snprintf(name, sizeof(name), "[%s]", line);
1816 		map = machine__new_module(self, start, name);
1817 		if (map == NULL)
1818 			goto out_delete_line;
1819 		dso__kernel_module_get_build_id(map->dso, self->root_dir);
1820 	}
1821 
1822 	free(line);
1823 	fclose(file);
1824 
1825 	return machine__set_modules_path(self);
1826 
1827 out_delete_line:
1828 	free(line);
1829 out_failure:
1830 	return -1;
1831 }
1832 
1833 int dso__load_vmlinux(struct dso *self, struct map *map,
1834 		      const char *vmlinux, symbol_filter_t filter)
1835 {
1836 	int err = -1, fd;
1837 	char symfs_vmlinux[PATH_MAX];
1838 
1839 	snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s/%s",
1840 		 symbol_conf.symfs, vmlinux);
1841 	fd = open(symfs_vmlinux, O_RDONLY);
1842 	if (fd < 0)
1843 		return -1;
1844 
1845 	dso__set_loaded(self, map->type);
1846 	err = dso__load_sym(self, map, symfs_vmlinux, fd, filter, 0, 0);
1847 	close(fd);
1848 
1849 	if (err > 0)
1850 		pr_debug("Using %s for symbols\n", symfs_vmlinux);
1851 
1852 	return err;
1853 }
1854 
1855 int dso__load_vmlinux_path(struct dso *self, struct map *map,
1856 			   symbol_filter_t filter)
1857 {
1858 	int i, err = 0;
1859 	char *filename;
1860 
1861 	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1862 		 vmlinux_path__nr_entries + 1);
1863 
1864 	filename = dso__build_id_filename(self, NULL, 0);
1865 	if (filename != NULL) {
1866 		err = dso__load_vmlinux(self, map, filename, filter);
1867 		if (err > 0) {
1868 			dso__set_long_name(self, filename);
1869 			goto out;
1870 		}
1871 		free(filename);
1872 	}
1873 
1874 	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1875 		err = dso__load_vmlinux(self, map, vmlinux_path[i], filter);
1876 		if (err > 0) {
1877 			dso__set_long_name(self, strdup(vmlinux_path[i]));
1878 			break;
1879 		}
1880 	}
1881 out:
1882 	return err;
1883 }
1884 
1885 static int dso__load_kernel_sym(struct dso *self, struct map *map,
1886 				symbol_filter_t filter)
1887 {
1888 	int err;
1889 	const char *kallsyms_filename = NULL;
1890 	char *kallsyms_allocated_filename = NULL;
1891 	/*
1892 	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
1893 	 * it and only it, reporting errors to the user if it cannot be used.
1894 	 *
1895 	 * For instance, try to analyse an ARM perf.data file _without_ a
1896 	 * build-id, or if the user specifies the wrong path to the right
1897 	 * vmlinux file, obviously we can't fallback to another vmlinux (a
1898 	 * x86_86 one, on the machine where analysis is being performed, say),
1899 	 * or worse, /proc/kallsyms.
1900 	 *
1901 	 * If the specified file _has_ a build-id and there is a build-id
1902 	 * section in the perf.data file, we will still do the expected
1903 	 * validation in dso__load_vmlinux and will bail out if they don't
1904 	 * match.
1905 	 */
1906 	if (symbol_conf.kallsyms_name != NULL) {
1907 		kallsyms_filename = symbol_conf.kallsyms_name;
1908 		goto do_kallsyms;
1909 	}
1910 
1911 	if (symbol_conf.vmlinux_name != NULL) {
1912 		err = dso__load_vmlinux(self, map,
1913 					symbol_conf.vmlinux_name, filter);
1914 		if (err > 0) {
1915 			dso__set_long_name(self,
1916 					   strdup(symbol_conf.vmlinux_name));
1917 			goto out_fixup;
1918 		}
1919 		return err;
1920 	}
1921 
1922 	if (vmlinux_path != NULL) {
1923 		err = dso__load_vmlinux_path(self, map, filter);
1924 		if (err > 0)
1925 			goto out_fixup;
1926 	}
1927 
1928 	/* do not try local files if a symfs was given */
1929 	if (symbol_conf.symfs[0] != 0)
1930 		return -1;
1931 
1932 	/*
1933 	 * Say the kernel DSO was created when processing the build-id header table,
1934 	 * we have a build-id, so check if it is the same as the running kernel,
1935 	 * using it if it is.
1936 	 */
1937 	if (self->has_build_id) {
1938 		u8 kallsyms_build_id[BUILD_ID_SIZE];
1939 		char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1940 
1941 		if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
1942 					 sizeof(kallsyms_build_id)) == 0) {
1943 			if (dso__build_id_equal(self, kallsyms_build_id)) {
1944 				kallsyms_filename = "/proc/kallsyms";
1945 				goto do_kallsyms;
1946 			}
1947 		}
1948 		/*
1949 		 * Now look if we have it on the build-id cache in
1950 		 * $HOME/.debug/[kernel.kallsyms].
1951 		 */
1952 		build_id__sprintf(self->build_id, sizeof(self->build_id),
1953 				  sbuild_id);
1954 
1955 		if (asprintf(&kallsyms_allocated_filename,
1956 			     "%s/.debug/[kernel.kallsyms]/%s",
1957 			     getenv("HOME"), sbuild_id) == -1) {
1958 			pr_err("Not enough memory for kallsyms file lookup\n");
1959 			return -1;
1960 		}
1961 
1962 		kallsyms_filename = kallsyms_allocated_filename;
1963 
1964 		if (access(kallsyms_filename, F_OK)) {
1965 			pr_err("No kallsyms or vmlinux with build-id %s "
1966 			       "was found\n", sbuild_id);
1967 			free(kallsyms_allocated_filename);
1968 			return -1;
1969 		}
1970 	} else {
1971 		/*
1972 		 * Last resort, if we don't have a build-id and couldn't find
1973 		 * any vmlinux file, try the running kernel kallsyms table.
1974 		 */
1975 		kallsyms_filename = "/proc/kallsyms";
1976 	}
1977 
1978 do_kallsyms:
1979 	err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
1980 	if (err > 0)
1981 		pr_debug("Using %s for symbols\n", kallsyms_filename);
1982 	free(kallsyms_allocated_filename);
1983 
1984 	if (err > 0) {
1985 out_fixup:
1986 		if (kallsyms_filename != NULL)
1987 			dso__set_long_name(self, strdup("[kernel.kallsyms]"));
1988 		map__fixup_start(map);
1989 		map__fixup_end(map);
1990 	}
1991 
1992 	return err;
1993 }
1994 
1995 static int dso__load_guest_kernel_sym(struct dso *self, struct map *map,
1996 				symbol_filter_t filter)
1997 {
1998 	int err;
1999 	const char *kallsyms_filename = NULL;
2000 	struct machine *machine;
2001 	char path[PATH_MAX];
2002 
2003 	if (!map->groups) {
2004 		pr_debug("Guest kernel map hasn't the point to groups\n");
2005 		return -1;
2006 	}
2007 	machine = map->groups->machine;
2008 
2009 	if (machine__is_default_guest(machine)) {
2010 		/*
2011 		 * if the user specified a vmlinux filename, use it and only
2012 		 * it, reporting errors to the user if it cannot be used.
2013 		 * Or use file guest_kallsyms inputted by user on commandline
2014 		 */
2015 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
2016 			err = dso__load_vmlinux(self, map,
2017 				symbol_conf.default_guest_vmlinux_name, filter);
2018 			goto out_try_fixup;
2019 		}
2020 
2021 		kallsyms_filename = symbol_conf.default_guest_kallsyms;
2022 		if (!kallsyms_filename)
2023 			return -1;
2024 	} else {
2025 		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2026 		kallsyms_filename = path;
2027 	}
2028 
2029 	err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
2030 	if (err > 0)
2031 		pr_debug("Using %s for symbols\n", kallsyms_filename);
2032 
2033 out_try_fixup:
2034 	if (err > 0) {
2035 		if (kallsyms_filename != NULL) {
2036 			machine__mmap_name(machine, path, sizeof(path));
2037 			dso__set_long_name(self, strdup(path));
2038 		}
2039 		map__fixup_start(map);
2040 		map__fixup_end(map);
2041 	}
2042 
2043 	return err;
2044 }
2045 
2046 static void dsos__add(struct list_head *head, struct dso *dso)
2047 {
2048 	list_add_tail(&dso->node, head);
2049 }
2050 
2051 static struct dso *dsos__find(struct list_head *head, const char *name)
2052 {
2053 	struct dso *pos;
2054 
2055 	list_for_each_entry(pos, head, node)
2056 		if (strcmp(pos->long_name, name) == 0)
2057 			return pos;
2058 	return NULL;
2059 }
2060 
2061 struct dso *__dsos__findnew(struct list_head *head, const char *name)
2062 {
2063 	struct dso *dso = dsos__find(head, name);
2064 
2065 	if (!dso) {
2066 		dso = dso__new(name);
2067 		if (dso != NULL) {
2068 			dsos__add(head, dso);
2069 			dso__set_basename(dso);
2070 		}
2071 	}
2072 
2073 	return dso;
2074 }
2075 
2076 size_t __dsos__fprintf(struct list_head *head, FILE *fp)
2077 {
2078 	struct dso *pos;
2079 	size_t ret = 0;
2080 
2081 	list_for_each_entry(pos, head, node) {
2082 		int i;
2083 		for (i = 0; i < MAP__NR_TYPES; ++i)
2084 			ret += dso__fprintf(pos, i, fp);
2085 	}
2086 
2087 	return ret;
2088 }
2089 
2090 size_t machines__fprintf_dsos(struct rb_root *self, FILE *fp)
2091 {
2092 	struct rb_node *nd;
2093 	size_t ret = 0;
2094 
2095 	for (nd = rb_first(self); nd; nd = rb_next(nd)) {
2096 		struct machine *pos = rb_entry(nd, struct machine, rb_node);
2097 		ret += __dsos__fprintf(&pos->kernel_dsos, fp);
2098 		ret += __dsos__fprintf(&pos->user_dsos, fp);
2099 	}
2100 
2101 	return ret;
2102 }
2103 
2104 static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
2105 				      bool with_hits)
2106 {
2107 	struct dso *pos;
2108 	size_t ret = 0;
2109 
2110 	list_for_each_entry(pos, head, node) {
2111 		if (with_hits && !pos->hit)
2112 			continue;
2113 		ret += dso__fprintf_buildid(pos, fp);
2114 		ret += fprintf(fp, " %s\n", pos->long_name);
2115 	}
2116 	return ret;
2117 }
2118 
2119 size_t machine__fprintf_dsos_buildid(struct machine *self, FILE *fp, bool with_hits)
2120 {
2121 	return __dsos__fprintf_buildid(&self->kernel_dsos, fp, with_hits) +
2122 	       __dsos__fprintf_buildid(&self->user_dsos, fp, with_hits);
2123 }
2124 
2125 size_t machines__fprintf_dsos_buildid(struct rb_root *self, FILE *fp, bool with_hits)
2126 {
2127 	struct rb_node *nd;
2128 	size_t ret = 0;
2129 
2130 	for (nd = rb_first(self); nd; nd = rb_next(nd)) {
2131 		struct machine *pos = rb_entry(nd, struct machine, rb_node);
2132 		ret += machine__fprintf_dsos_buildid(pos, fp, with_hits);
2133 	}
2134 	return ret;
2135 }
2136 
2137 struct dso *dso__new_kernel(const char *name)
2138 {
2139 	struct dso *self = dso__new(name ?: "[kernel.kallsyms]");
2140 
2141 	if (self != NULL) {
2142 		dso__set_short_name(self, "[kernel]");
2143 		self->kernel = DSO_TYPE_KERNEL;
2144 	}
2145 
2146 	return self;
2147 }
2148 
2149 static struct dso *dso__new_guest_kernel(struct machine *machine,
2150 					const char *name)
2151 {
2152 	char bf[PATH_MAX];
2153 	struct dso *self = dso__new(name ?: machine__mmap_name(machine, bf, sizeof(bf)));
2154 
2155 	if (self != NULL) {
2156 		dso__set_short_name(self, "[guest.kernel]");
2157 		self->kernel = DSO_TYPE_GUEST_KERNEL;
2158 	}
2159 
2160 	return self;
2161 }
2162 
2163 void dso__read_running_kernel_build_id(struct dso *self, struct machine *machine)
2164 {
2165 	char path[PATH_MAX];
2166 
2167 	if (machine__is_default_guest(machine))
2168 		return;
2169 	sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
2170 	if (sysfs__read_build_id(path, self->build_id,
2171 				 sizeof(self->build_id)) == 0)
2172 		self->has_build_id = true;
2173 }
2174 
2175 static struct dso *machine__create_kernel(struct machine *self)
2176 {
2177 	const char *vmlinux_name = NULL;
2178 	struct dso *kernel;
2179 
2180 	if (machine__is_host(self)) {
2181 		vmlinux_name = symbol_conf.vmlinux_name;
2182 		kernel = dso__new_kernel(vmlinux_name);
2183 	} else {
2184 		if (machine__is_default_guest(self))
2185 			vmlinux_name = symbol_conf.default_guest_vmlinux_name;
2186 		kernel = dso__new_guest_kernel(self, vmlinux_name);
2187 	}
2188 
2189 	if (kernel != NULL) {
2190 		dso__read_running_kernel_build_id(kernel, self);
2191 		dsos__add(&self->kernel_dsos, kernel);
2192 	}
2193 	return kernel;
2194 }
2195 
2196 struct process_args {
2197 	u64 start;
2198 };
2199 
2200 static int symbol__in_kernel(void *arg, const char *name,
2201 			     char type __used, u64 start, u64 end __used)
2202 {
2203 	struct process_args *args = arg;
2204 
2205 	if (strchr(name, '['))
2206 		return 0;
2207 
2208 	args->start = start;
2209 	return 1;
2210 }
2211 
2212 /* Figure out the start address of kernel map from /proc/kallsyms */
2213 static u64 machine__get_kernel_start_addr(struct machine *machine)
2214 {
2215 	const char *filename;
2216 	char path[PATH_MAX];
2217 	struct process_args args;
2218 
2219 	if (machine__is_host(machine)) {
2220 		filename = "/proc/kallsyms";
2221 	} else {
2222 		if (machine__is_default_guest(machine))
2223 			filename = (char *)symbol_conf.default_guest_kallsyms;
2224 		else {
2225 			sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2226 			filename = path;
2227 		}
2228 	}
2229 
2230 	if (kallsyms__parse(filename, &args, symbol__in_kernel) <= 0)
2231 		return 0;
2232 
2233 	return args.start;
2234 }
2235 
2236 int __machine__create_kernel_maps(struct machine *self, struct dso *kernel)
2237 {
2238 	enum map_type type;
2239 	u64 start = machine__get_kernel_start_addr(self);
2240 
2241 	for (type = 0; type < MAP__NR_TYPES; ++type) {
2242 		struct kmap *kmap;
2243 
2244 		self->vmlinux_maps[type] = map__new2(start, kernel, type);
2245 		if (self->vmlinux_maps[type] == NULL)
2246 			return -1;
2247 
2248 		self->vmlinux_maps[type]->map_ip =
2249 			self->vmlinux_maps[type]->unmap_ip = identity__map_ip;
2250 
2251 		kmap = map__kmap(self->vmlinux_maps[type]);
2252 		kmap->kmaps = &self->kmaps;
2253 		map_groups__insert(&self->kmaps, self->vmlinux_maps[type]);
2254 	}
2255 
2256 	return 0;
2257 }
2258 
2259 void machine__destroy_kernel_maps(struct machine *self)
2260 {
2261 	enum map_type type;
2262 
2263 	for (type = 0; type < MAP__NR_TYPES; ++type) {
2264 		struct kmap *kmap;
2265 
2266 		if (self->vmlinux_maps[type] == NULL)
2267 			continue;
2268 
2269 		kmap = map__kmap(self->vmlinux_maps[type]);
2270 		map_groups__remove(&self->kmaps, self->vmlinux_maps[type]);
2271 		if (kmap->ref_reloc_sym) {
2272 			/*
2273 			 * ref_reloc_sym is shared among all maps, so free just
2274 			 * on one of them.
2275 			 */
2276 			if (type == MAP__FUNCTION) {
2277 				free((char *)kmap->ref_reloc_sym->name);
2278 				kmap->ref_reloc_sym->name = NULL;
2279 				free(kmap->ref_reloc_sym);
2280 			}
2281 			kmap->ref_reloc_sym = NULL;
2282 		}
2283 
2284 		map__delete(self->vmlinux_maps[type]);
2285 		self->vmlinux_maps[type] = NULL;
2286 	}
2287 }
2288 
2289 int machine__create_kernel_maps(struct machine *self)
2290 {
2291 	struct dso *kernel = machine__create_kernel(self);
2292 
2293 	if (kernel == NULL ||
2294 	    __machine__create_kernel_maps(self, kernel) < 0)
2295 		return -1;
2296 
2297 	if (symbol_conf.use_modules && machine__create_modules(self) < 0)
2298 		pr_debug("Problems creating module maps, continuing anyway...\n");
2299 	/*
2300 	 * Now that we have all the maps created, just set the ->end of them:
2301 	 */
2302 	map_groups__fixup_end(&self->kmaps);
2303 	return 0;
2304 }
2305 
2306 static void vmlinux_path__exit(void)
2307 {
2308 	while (--vmlinux_path__nr_entries >= 0) {
2309 		free(vmlinux_path[vmlinux_path__nr_entries]);
2310 		vmlinux_path[vmlinux_path__nr_entries] = NULL;
2311 	}
2312 
2313 	free(vmlinux_path);
2314 	vmlinux_path = NULL;
2315 }
2316 
2317 static int vmlinux_path__init(void)
2318 {
2319 	struct utsname uts;
2320 	char bf[PATH_MAX];
2321 
2322 	vmlinux_path = malloc(sizeof(char *) * 5);
2323 	if (vmlinux_path == NULL)
2324 		return -1;
2325 
2326 	vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
2327 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2328 		goto out_fail;
2329 	++vmlinux_path__nr_entries;
2330 	vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
2331 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2332 		goto out_fail;
2333 	++vmlinux_path__nr_entries;
2334 
2335 	/* only try running kernel version if no symfs was given */
2336 	if (symbol_conf.symfs[0] != 0)
2337 		return 0;
2338 
2339 	if (uname(&uts) < 0)
2340 		return -1;
2341 
2342 	snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
2343 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2344 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2345 		goto out_fail;
2346 	++vmlinux_path__nr_entries;
2347 	snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
2348 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2349 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2350 		goto out_fail;
2351 	++vmlinux_path__nr_entries;
2352 	snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
2353 		 uts.release);
2354 	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
2355 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2356 		goto out_fail;
2357 	++vmlinux_path__nr_entries;
2358 
2359 	return 0;
2360 
2361 out_fail:
2362 	vmlinux_path__exit();
2363 	return -1;
2364 }
2365 
2366 size_t machine__fprintf_vmlinux_path(struct machine *self, FILE *fp)
2367 {
2368 	int i;
2369 	size_t printed = 0;
2370 	struct dso *kdso = self->vmlinux_maps[MAP__FUNCTION]->dso;
2371 
2372 	if (kdso->has_build_id) {
2373 		char filename[PATH_MAX];
2374 		if (dso__build_id_filename(kdso, filename, sizeof(filename)))
2375 			printed += fprintf(fp, "[0] %s\n", filename);
2376 	}
2377 
2378 	for (i = 0; i < vmlinux_path__nr_entries; ++i)
2379 		printed += fprintf(fp, "[%d] %s\n",
2380 				   i + kdso->has_build_id, vmlinux_path[i]);
2381 
2382 	return printed;
2383 }
2384 
2385 static int setup_list(struct strlist **list, const char *list_str,
2386 		      const char *list_name)
2387 {
2388 	if (list_str == NULL)
2389 		return 0;
2390 
2391 	*list = strlist__new(true, list_str);
2392 	if (!*list) {
2393 		pr_err("problems parsing %s list\n", list_name);
2394 		return -1;
2395 	}
2396 	return 0;
2397 }
2398 
2399 int symbol__init(void)
2400 {
2401 	const char *symfs;
2402 
2403 	if (symbol_conf.initialized)
2404 		return 0;
2405 
2406 	elf_version(EV_CURRENT);
2407 	if (symbol_conf.sort_by_name)
2408 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2409 					  sizeof(struct symbol));
2410 
2411 	if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
2412 		return -1;
2413 
2414 	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2415 		pr_err("'.' is the only non valid --field-separator argument\n");
2416 		return -1;
2417 	}
2418 
2419 	if (setup_list(&symbol_conf.dso_list,
2420 		       symbol_conf.dso_list_str, "dso") < 0)
2421 		return -1;
2422 
2423 	if (setup_list(&symbol_conf.comm_list,
2424 		       symbol_conf.comm_list_str, "comm") < 0)
2425 		goto out_free_dso_list;
2426 
2427 	if (setup_list(&symbol_conf.sym_list,
2428 		       symbol_conf.sym_list_str, "symbol") < 0)
2429 		goto out_free_comm_list;
2430 
2431 	/*
2432 	 * A path to symbols of "/" is identical to ""
2433 	 * reset here for simplicity.
2434 	 */
2435 	symfs = realpath(symbol_conf.symfs, NULL);
2436 	if (symfs == NULL)
2437 		symfs = symbol_conf.symfs;
2438 	if (strcmp(symfs, "/") == 0)
2439 		symbol_conf.symfs = "";
2440 	if (symfs != symbol_conf.symfs)
2441 		free((void *)symfs);
2442 
2443 	symbol_conf.initialized = true;
2444 	return 0;
2445 
2446 out_free_dso_list:
2447 	strlist__delete(symbol_conf.dso_list);
2448 out_free_comm_list:
2449 	strlist__delete(symbol_conf.comm_list);
2450 	return -1;
2451 }
2452 
2453 void symbol__exit(void)
2454 {
2455 	if (!symbol_conf.initialized)
2456 		return;
2457 	strlist__delete(symbol_conf.sym_list);
2458 	strlist__delete(symbol_conf.dso_list);
2459 	strlist__delete(symbol_conf.comm_list);
2460 	vmlinux_path__exit();
2461 	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2462 	symbol_conf.initialized = false;
2463 }
2464 
2465 int machines__create_kernel_maps(struct rb_root *self, pid_t pid)
2466 {
2467 	struct machine *machine = machines__findnew(self, pid);
2468 
2469 	if (machine == NULL)
2470 		return -1;
2471 
2472 	return machine__create_kernel_maps(machine);
2473 }
2474 
2475 static int hex(char ch)
2476 {
2477 	if ((ch >= '0') && (ch <= '9'))
2478 		return ch - '0';
2479 	if ((ch >= 'a') && (ch <= 'f'))
2480 		return ch - 'a' + 10;
2481 	if ((ch >= 'A') && (ch <= 'F'))
2482 		return ch - 'A' + 10;
2483 	return -1;
2484 }
2485 
2486 /*
2487  * While we find nice hex chars, build a long_val.
2488  * Return number of chars processed.
2489  */
2490 int hex2u64(const char *ptr, u64 *long_val)
2491 {
2492 	const char *p = ptr;
2493 	*long_val = 0;
2494 
2495 	while (*p) {
2496 		const int hex_val = hex(*p);
2497 
2498 		if (hex_val < 0)
2499 			break;
2500 
2501 		*long_val = (*long_val << 4) | hex_val;
2502 		p++;
2503 	}
2504 
2505 	return p - ptr;
2506 }
2507 
2508 char *strxfrchar(char *s, char from, char to)
2509 {
2510 	char *p = s;
2511 
2512 	while ((p = strchr(p, from)) != NULL)
2513 		*p++ = to;
2514 
2515 	return s;
2516 }
2517 
2518 int machines__create_guest_kernel_maps(struct rb_root *self)
2519 {
2520 	int ret = 0;
2521 	struct dirent **namelist = NULL;
2522 	int i, items = 0;
2523 	char path[PATH_MAX];
2524 	pid_t pid;
2525 
2526 	if (symbol_conf.default_guest_vmlinux_name ||
2527 	    symbol_conf.default_guest_modules ||
2528 	    symbol_conf.default_guest_kallsyms) {
2529 		machines__create_kernel_maps(self, DEFAULT_GUEST_KERNEL_ID);
2530 	}
2531 
2532 	if (symbol_conf.guestmount) {
2533 		items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
2534 		if (items <= 0)
2535 			return -ENOENT;
2536 		for (i = 0; i < items; i++) {
2537 			if (!isdigit(namelist[i]->d_name[0])) {
2538 				/* Filter out . and .. */
2539 				continue;
2540 			}
2541 			pid = atoi(namelist[i]->d_name);
2542 			sprintf(path, "%s/%s/proc/kallsyms",
2543 				symbol_conf.guestmount,
2544 				namelist[i]->d_name);
2545 			ret = access(path, R_OK);
2546 			if (ret) {
2547 				pr_debug("Can't access file %s\n", path);
2548 				goto failure;
2549 			}
2550 			machines__create_kernel_maps(self, pid);
2551 		}
2552 failure:
2553 		free(namelist);
2554 	}
2555 
2556 	return ret;
2557 }
2558 
2559 void machines__destroy_guest_kernel_maps(struct rb_root *self)
2560 {
2561 	struct rb_node *next = rb_first(self);
2562 
2563 	while (next) {
2564 		struct machine *pos = rb_entry(next, struct machine, rb_node);
2565 
2566 		next = rb_next(&pos->rb_node);
2567 		rb_erase(&pos->rb_node, self);
2568 		machine__delete(pos);
2569 	}
2570 }
2571 
2572 int machine__load_kallsyms(struct machine *self, const char *filename,
2573 			   enum map_type type, symbol_filter_t filter)
2574 {
2575 	struct map *map = self->vmlinux_maps[type];
2576 	int ret = dso__load_kallsyms(map->dso, filename, map, filter);
2577 
2578 	if (ret > 0) {
2579 		dso__set_loaded(map->dso, type);
2580 		/*
2581 		 * Since /proc/kallsyms will have multiple sessions for the
2582 		 * kernel, with modules between them, fixup the end of all
2583 		 * sections.
2584 		 */
2585 		__map_groups__fixup_end(&self->kmaps, type);
2586 	}
2587 
2588 	return ret;
2589 }
2590 
2591 int machine__load_vmlinux_path(struct machine *self, enum map_type type,
2592 			       symbol_filter_t filter)
2593 {
2594 	struct map *map = self->vmlinux_maps[type];
2595 	int ret = dso__load_vmlinux_path(map->dso, map, filter);
2596 
2597 	if (ret > 0) {
2598 		dso__set_loaded(map->dso, type);
2599 		map__reloc_vmlinux(map);
2600 	}
2601 
2602 	return ret;
2603 }
2604