xref: /linux/tools/perf/util/map.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 #include "symbol.h"
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <limits.h>
5 #include <stdlib.h>
6 #include <string.h>
7 #include <stdio.h>
8 #include <unistd.h>
9 #include "map.h"
10 #include "thread.h"
11 #include "strlist.h"
12 #include "vdso.h"
13 #include "build-id.h"
14 #include "util.h"
15 #include "debug.h"
16 #include "machine.h"
17 #include <linux/string.h>
18 
19 static void __maps__insert(struct maps *maps, struct map *map);
20 
21 const char *map_type__name[MAP__NR_TYPES] = {
22 	[MAP__FUNCTION] = "Functions",
23 	[MAP__VARIABLE] = "Variables",
24 };
25 
26 static inline int is_anon_memory(const char *filename)
27 {
28 	return !strcmp(filename, "//anon") ||
29 	       !strcmp(filename, "/dev/zero (deleted)") ||
30 	       !strcmp(filename, "/anon_hugepage (deleted)");
31 }
32 
33 static inline int is_no_dso_memory(const char *filename)
34 {
35 	return !strncmp(filename, "[stack", 6) ||
36 	       !strncmp(filename, "/SYSV",5)   ||
37 	       !strcmp(filename, "[heap]");
38 }
39 
40 static inline int is_android_lib(const char *filename)
41 {
42 	return !strncmp(filename, "/data/app-lib", 13) ||
43 	       !strncmp(filename, "/system/lib", 11);
44 }
45 
46 static inline bool replace_android_lib(const char *filename, char *newfilename)
47 {
48 	const char *libname;
49 	char *app_abi;
50 	size_t app_abi_length, new_length;
51 	size_t lib_length = 0;
52 
53 	libname  = strrchr(filename, '/');
54 	if (libname)
55 		lib_length = strlen(libname);
56 
57 	app_abi = getenv("APP_ABI");
58 	if (!app_abi)
59 		return false;
60 
61 	app_abi_length = strlen(app_abi);
62 
63 	if (!strncmp(filename, "/data/app-lib", 13)) {
64 		char *apk_path;
65 
66 		if (!app_abi_length)
67 			return false;
68 
69 		new_length = 7 + app_abi_length + lib_length;
70 
71 		apk_path = getenv("APK_PATH");
72 		if (apk_path) {
73 			new_length += strlen(apk_path) + 1;
74 			if (new_length > PATH_MAX)
75 				return false;
76 			snprintf(newfilename, new_length,
77 				 "%s/libs/%s/%s", apk_path, app_abi, libname);
78 		} else {
79 			if (new_length > PATH_MAX)
80 				return false;
81 			snprintf(newfilename, new_length,
82 				 "libs/%s/%s", app_abi, libname);
83 		}
84 		return true;
85 	}
86 
87 	if (!strncmp(filename, "/system/lib/", 11)) {
88 		char *ndk, *app;
89 		const char *arch;
90 		size_t ndk_length;
91 		size_t app_length;
92 
93 		ndk = getenv("NDK_ROOT");
94 		app = getenv("APP_PLATFORM");
95 
96 		if (!(ndk && app))
97 			return false;
98 
99 		ndk_length = strlen(ndk);
100 		app_length = strlen(app);
101 
102 		if (!(ndk_length && app_length && app_abi_length))
103 			return false;
104 
105 		arch = !strncmp(app_abi, "arm", 3) ? "arm" :
106 		       !strncmp(app_abi, "mips", 4) ? "mips" :
107 		       !strncmp(app_abi, "x86", 3) ? "x86" : NULL;
108 
109 		if (!arch)
110 			return false;
111 
112 		new_length = 27 + ndk_length +
113 			     app_length + lib_length
114 			   + strlen(arch);
115 
116 		if (new_length > PATH_MAX)
117 			return false;
118 		snprintf(newfilename, new_length,
119 			"%s/platforms/%s/arch-%s/usr/lib/%s",
120 			ndk, app, arch, libname);
121 
122 		return true;
123 	}
124 	return false;
125 }
126 
127 void map__init(struct map *map, enum map_type type,
128 	       u64 start, u64 end, u64 pgoff, struct dso *dso)
129 {
130 	map->type     = type;
131 	map->start    = start;
132 	map->end      = end;
133 	map->pgoff    = pgoff;
134 	map->reloc    = 0;
135 	map->dso      = dso__get(dso);
136 	map->map_ip   = map__map_ip;
137 	map->unmap_ip = map__unmap_ip;
138 	RB_CLEAR_NODE(&map->rb_node);
139 	map->groups   = NULL;
140 	map->erange_warned = false;
141 	atomic_set(&map->refcnt, 1);
142 }
143 
144 struct map *map__new(struct machine *machine, u64 start, u64 len,
145 		     u64 pgoff, u32 pid, u32 d_maj, u32 d_min, u64 ino,
146 		     u64 ino_gen, u32 prot, u32 flags, char *filename,
147 		     enum map_type type, struct thread *thread)
148 {
149 	struct map *map = malloc(sizeof(*map));
150 
151 	if (map != NULL) {
152 		char newfilename[PATH_MAX];
153 		struct dso *dso;
154 		int anon, no_dso, vdso, android;
155 
156 		android = is_android_lib(filename);
157 		anon = is_anon_memory(filename);
158 		vdso = is_vdso_map(filename);
159 		no_dso = is_no_dso_memory(filename);
160 
161 		map->maj = d_maj;
162 		map->min = d_min;
163 		map->ino = ino;
164 		map->ino_generation = ino_gen;
165 		map->prot = prot;
166 		map->flags = flags;
167 
168 		if ((anon || no_dso) && type == MAP__FUNCTION) {
169 			snprintf(newfilename, sizeof(newfilename), "/tmp/perf-%d.map", pid);
170 			filename = newfilename;
171 		}
172 
173 		if (android) {
174 			if (replace_android_lib(filename, newfilename))
175 				filename = newfilename;
176 		}
177 
178 		if (vdso) {
179 			pgoff = 0;
180 			dso = machine__findnew_vdso(machine, thread);
181 		} else
182 			dso = machine__findnew_dso(machine, filename);
183 
184 		if (dso == NULL)
185 			goto out_delete;
186 
187 		map__init(map, type, start, start + len, pgoff, dso);
188 
189 		if (anon || no_dso) {
190 			map->map_ip = map->unmap_ip = identity__map_ip;
191 
192 			/*
193 			 * Set memory without DSO as loaded. All map__find_*
194 			 * functions still return NULL, and we avoid the
195 			 * unnecessary map__load warning.
196 			 */
197 			if (type != MAP__FUNCTION)
198 				dso__set_loaded(dso, map->type);
199 		}
200 		dso__put(dso);
201 	}
202 	return map;
203 out_delete:
204 	free(map);
205 	return NULL;
206 }
207 
208 /*
209  * Constructor variant for modules (where we know from /proc/modules where
210  * they are loaded) and for vmlinux, where only after we load all the
211  * symbols we'll know where it starts and ends.
212  */
213 struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
214 {
215 	struct map *map = calloc(1, (sizeof(*map) +
216 				     (dso->kernel ? sizeof(struct kmap) : 0)));
217 	if (map != NULL) {
218 		/*
219 		 * ->end will be filled after we load all the symbols
220 		 */
221 		map__init(map, type, start, 0, 0, dso);
222 	}
223 
224 	return map;
225 }
226 
227 static void map__exit(struct map *map)
228 {
229 	BUG_ON(!RB_EMPTY_NODE(&map->rb_node));
230 	dso__zput(map->dso);
231 }
232 
233 void map__delete(struct map *map)
234 {
235 	map__exit(map);
236 	free(map);
237 }
238 
239 void map__put(struct map *map)
240 {
241 	if (map && atomic_dec_and_test(&map->refcnt))
242 		map__delete(map);
243 }
244 
245 void map__fixup_start(struct map *map)
246 {
247 	struct rb_root *symbols = &map->dso->symbols[map->type];
248 	struct rb_node *nd = rb_first(symbols);
249 	if (nd != NULL) {
250 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
251 		map->start = sym->start;
252 	}
253 }
254 
255 void map__fixup_end(struct map *map)
256 {
257 	struct rb_root *symbols = &map->dso->symbols[map->type];
258 	struct rb_node *nd = rb_last(symbols);
259 	if (nd != NULL) {
260 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
261 		map->end = sym->end;
262 	}
263 }
264 
265 #define DSO__DELETED "(deleted)"
266 
267 int map__load(struct map *map, symbol_filter_t filter)
268 {
269 	const char *name = map->dso->long_name;
270 	int nr;
271 
272 	if (dso__loaded(map->dso, map->type))
273 		return 0;
274 
275 	nr = dso__load(map->dso, map, filter);
276 	if (nr < 0) {
277 		if (map->dso->has_build_id) {
278 			char sbuild_id[BUILD_ID_SIZE * 2 + 1];
279 
280 			build_id__sprintf(map->dso->build_id,
281 					  sizeof(map->dso->build_id),
282 					  sbuild_id);
283 			pr_warning("%s with build id %s not found",
284 				   name, sbuild_id);
285 		} else
286 			pr_warning("Failed to open %s", name);
287 
288 		pr_warning(", continuing without symbols\n");
289 		return -1;
290 	} else if (nr == 0) {
291 #ifdef HAVE_LIBELF_SUPPORT
292 		const size_t len = strlen(name);
293 		const size_t real_len = len - sizeof(DSO__DELETED);
294 
295 		if (len > sizeof(DSO__DELETED) &&
296 		    strcmp(name + real_len + 1, DSO__DELETED) == 0) {
297 			pr_warning("%.*s was updated (is prelink enabled?). "
298 				"Restart the long running apps that use it!\n",
299 				   (int)real_len, name);
300 		} else {
301 			pr_warning("no symbols found in %s, maybe install "
302 				   "a debug package?\n", name);
303 		}
304 #endif
305 		return -1;
306 	}
307 
308 	return 0;
309 }
310 
311 int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
312 {
313 	return strcmp(namea, nameb);
314 }
315 
316 struct symbol *map__find_symbol(struct map *map, u64 addr,
317 				symbol_filter_t filter)
318 {
319 	if (map__load(map, filter) < 0)
320 		return NULL;
321 
322 	return dso__find_symbol(map->dso, map->type, addr);
323 }
324 
325 struct symbol *map__find_symbol_by_name(struct map *map, const char *name,
326 					symbol_filter_t filter)
327 {
328 	if (map__load(map, filter) < 0)
329 		return NULL;
330 
331 	if (!dso__sorted_by_name(map->dso, map->type))
332 		dso__sort_by_name(map->dso, map->type);
333 
334 	return dso__find_symbol_by_name(map->dso, map->type, name);
335 }
336 
337 struct map *map__clone(struct map *map)
338 {
339 	return memdup(map, sizeof(*map));
340 }
341 
342 int map__overlap(struct map *l, struct map *r)
343 {
344 	if (l->start > r->start) {
345 		struct map *t = l;
346 		l = r;
347 		r = t;
348 	}
349 
350 	if (l->end > r->start)
351 		return 1;
352 
353 	return 0;
354 }
355 
356 size_t map__fprintf(struct map *map, FILE *fp)
357 {
358 	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
359 		       map->start, map->end, map->pgoff, map->dso->name);
360 }
361 
362 size_t map__fprintf_dsoname(struct map *map, FILE *fp)
363 {
364 	const char *dsoname = "[unknown]";
365 
366 	if (map && map->dso && (map->dso->name || map->dso->long_name)) {
367 		if (symbol_conf.show_kernel_path && map->dso->long_name)
368 			dsoname = map->dso->long_name;
369 		else if (map->dso->name)
370 			dsoname = map->dso->name;
371 	}
372 
373 	return fprintf(fp, "%s", dsoname);
374 }
375 
376 int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
377 			 FILE *fp)
378 {
379 	char *srcline;
380 	int ret = 0;
381 
382 	if (map && map->dso) {
383 		srcline = get_srcline(map->dso,
384 				      map__rip_2objdump(map, addr), NULL, true);
385 		if (srcline != SRCLINE_UNKNOWN)
386 			ret = fprintf(fp, "%s%s", prefix, srcline);
387 		free_srcline(srcline);
388 	}
389 	return ret;
390 }
391 
392 /**
393  * map__rip_2objdump - convert symbol start address to objdump address.
394  * @map: memory map
395  * @rip: symbol start address
396  *
397  * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
398  * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
399  * relative to section start.
400  *
401  * Return: Address suitable for passing to "objdump --start-address="
402  */
403 u64 map__rip_2objdump(struct map *map, u64 rip)
404 {
405 	if (!map->dso->adjust_symbols)
406 		return rip;
407 
408 	if (map->dso->rel)
409 		return rip - map->pgoff;
410 
411 	return map->unmap_ip(map, rip) - map->reloc;
412 }
413 
414 /**
415  * map__objdump_2mem - convert objdump address to a memory address.
416  * @map: memory map
417  * @ip: objdump address
418  *
419  * Closely related to map__rip_2objdump(), this function takes an address from
420  * objdump and converts it to a memory address.  Note this assumes that @map
421  * contains the address.  To be sure the result is valid, check it forwards
422  * e.g. map__rip_2objdump(map->map_ip(map, map__objdump_2mem(map, ip))) == ip
423  *
424  * Return: Memory address.
425  */
426 u64 map__objdump_2mem(struct map *map, u64 ip)
427 {
428 	if (!map->dso->adjust_symbols)
429 		return map->unmap_ip(map, ip);
430 
431 	if (map->dso->rel)
432 		return map->unmap_ip(map, ip + map->pgoff);
433 
434 	return ip + map->reloc;
435 }
436 
437 static void maps__init(struct maps *maps)
438 {
439 	maps->entries = RB_ROOT;
440 	pthread_rwlock_init(&maps->lock, NULL);
441 }
442 
443 void map_groups__init(struct map_groups *mg, struct machine *machine)
444 {
445 	int i;
446 	for (i = 0; i < MAP__NR_TYPES; ++i) {
447 		maps__init(&mg->maps[i]);
448 	}
449 	mg->machine = machine;
450 	atomic_set(&mg->refcnt, 1);
451 }
452 
453 static void __maps__purge(struct maps *maps)
454 {
455 	struct rb_root *root = &maps->entries;
456 	struct rb_node *next = rb_first(root);
457 
458 	while (next) {
459 		struct map *pos = rb_entry(next, struct map, rb_node);
460 
461 		next = rb_next(&pos->rb_node);
462 		rb_erase_init(&pos->rb_node, root);
463 		map__put(pos);
464 	}
465 }
466 
467 static void maps__exit(struct maps *maps)
468 {
469 	pthread_rwlock_wrlock(&maps->lock);
470 	__maps__purge(maps);
471 	pthread_rwlock_unlock(&maps->lock);
472 }
473 
474 void map_groups__exit(struct map_groups *mg)
475 {
476 	int i;
477 
478 	for (i = 0; i < MAP__NR_TYPES; ++i)
479 		maps__exit(&mg->maps[i]);
480 }
481 
482 bool map_groups__empty(struct map_groups *mg)
483 {
484 	int i;
485 
486 	for (i = 0; i < MAP__NR_TYPES; ++i) {
487 		if (maps__first(&mg->maps[i]))
488 			return false;
489 	}
490 
491 	return true;
492 }
493 
494 struct map_groups *map_groups__new(struct machine *machine)
495 {
496 	struct map_groups *mg = malloc(sizeof(*mg));
497 
498 	if (mg != NULL)
499 		map_groups__init(mg, machine);
500 
501 	return mg;
502 }
503 
504 void map_groups__delete(struct map_groups *mg)
505 {
506 	map_groups__exit(mg);
507 	free(mg);
508 }
509 
510 void map_groups__put(struct map_groups *mg)
511 {
512 	if (mg && atomic_dec_and_test(&mg->refcnt))
513 		map_groups__delete(mg);
514 }
515 
516 struct symbol *map_groups__find_symbol(struct map_groups *mg,
517 				       enum map_type type, u64 addr,
518 				       struct map **mapp,
519 				       symbol_filter_t filter)
520 {
521 	struct map *map = map_groups__find(mg, type, addr);
522 
523 	/* Ensure map is loaded before using map->map_ip */
524 	if (map != NULL && map__load(map, filter) >= 0) {
525 		if (mapp != NULL)
526 			*mapp = map;
527 		return map__find_symbol(map, map->map_ip(map, addr), filter);
528 	}
529 
530 	return NULL;
531 }
532 
533 struct symbol *map_groups__find_symbol_by_name(struct map_groups *mg,
534 					       enum map_type type,
535 					       const char *name,
536 					       struct map **mapp,
537 					       symbol_filter_t filter)
538 {
539 	struct maps *maps = &mg->maps[type];
540 	struct symbol *sym;
541 	struct rb_node *nd;
542 
543 	pthread_rwlock_rdlock(&maps->lock);
544 
545 	for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
546 		struct map *pos = rb_entry(nd, struct map, rb_node);
547 
548 		sym = map__find_symbol_by_name(pos, name, filter);
549 
550 		if (sym == NULL)
551 			continue;
552 		if (mapp != NULL)
553 			*mapp = pos;
554 		goto out;
555 	}
556 
557 	sym = NULL;
558 out:
559 	pthread_rwlock_unlock(&maps->lock);
560 	return sym;
561 }
562 
563 int map_groups__find_ams(struct addr_map_symbol *ams, symbol_filter_t filter)
564 {
565 	if (ams->addr < ams->map->start || ams->addr >= ams->map->end) {
566 		if (ams->map->groups == NULL)
567 			return -1;
568 		ams->map = map_groups__find(ams->map->groups, ams->map->type,
569 					    ams->addr);
570 		if (ams->map == NULL)
571 			return -1;
572 	}
573 
574 	ams->al_addr = ams->map->map_ip(ams->map, ams->addr);
575 	ams->sym = map__find_symbol(ams->map, ams->al_addr, filter);
576 
577 	return ams->sym ? 0 : -1;
578 }
579 
580 static size_t maps__fprintf(struct maps *maps, FILE *fp)
581 {
582 	size_t printed = 0;
583 	struct rb_node *nd;
584 
585 	pthread_rwlock_rdlock(&maps->lock);
586 
587 	for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
588 		struct map *pos = rb_entry(nd, struct map, rb_node);
589 		printed += fprintf(fp, "Map:");
590 		printed += map__fprintf(pos, fp);
591 		if (verbose > 2) {
592 			printed += dso__fprintf(pos->dso, pos->type, fp);
593 			printed += fprintf(fp, "--\n");
594 		}
595 	}
596 
597 	pthread_rwlock_unlock(&maps->lock);
598 
599 	return printed;
600 }
601 
602 size_t __map_groups__fprintf_maps(struct map_groups *mg, enum map_type type,
603 				  FILE *fp)
604 {
605 	size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
606 	return printed += maps__fprintf(&mg->maps[type], fp);
607 }
608 
609 size_t map_groups__fprintf(struct map_groups *mg, FILE *fp)
610 {
611 	size_t printed = 0, i;
612 	for (i = 0; i < MAP__NR_TYPES; ++i)
613 		printed += __map_groups__fprintf_maps(mg, i, fp);
614 	return printed;
615 }
616 
617 static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
618 {
619 	struct rb_root *root;
620 	struct rb_node *next;
621 	int err = 0;
622 
623 	pthread_rwlock_wrlock(&maps->lock);
624 
625 	root = &maps->entries;
626 	next = rb_first(root);
627 
628 	while (next) {
629 		struct map *pos = rb_entry(next, struct map, rb_node);
630 		next = rb_next(&pos->rb_node);
631 
632 		if (!map__overlap(pos, map))
633 			continue;
634 
635 		if (verbose >= 2) {
636 			fputs("overlapping maps:\n", fp);
637 			map__fprintf(map, fp);
638 			map__fprintf(pos, fp);
639 		}
640 
641 		rb_erase_init(&pos->rb_node, root);
642 		/*
643 		 * Now check if we need to create new maps for areas not
644 		 * overlapped by the new map:
645 		 */
646 		if (map->start > pos->start) {
647 			struct map *before = map__clone(pos);
648 
649 			if (before == NULL) {
650 				err = -ENOMEM;
651 				goto put_map;
652 			}
653 
654 			before->end = map->start;
655 			__maps__insert(maps, before);
656 			if (verbose >= 2)
657 				map__fprintf(before, fp);
658 		}
659 
660 		if (map->end < pos->end) {
661 			struct map *after = map__clone(pos);
662 
663 			if (after == NULL) {
664 				err = -ENOMEM;
665 				goto put_map;
666 			}
667 
668 			after->start = map->end;
669 			__maps__insert(maps, after);
670 			if (verbose >= 2)
671 				map__fprintf(after, fp);
672 		}
673 put_map:
674 		map__put(pos);
675 
676 		if (err)
677 			goto out;
678 	}
679 
680 	err = 0;
681 out:
682 	pthread_rwlock_unlock(&maps->lock);
683 	return err;
684 }
685 
686 int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
687 				   FILE *fp)
688 {
689 	return maps__fixup_overlappings(&mg->maps[map->type], map, fp);
690 }
691 
692 /*
693  * XXX This should not really _copy_ te maps, but refcount them.
694  */
695 int map_groups__clone(struct map_groups *mg,
696 		      struct map_groups *parent, enum map_type type)
697 {
698 	int err = -ENOMEM;
699 	struct map *map;
700 	struct maps *maps = &parent->maps[type];
701 
702 	pthread_rwlock_rdlock(&maps->lock);
703 
704 	for (map = maps__first(maps); map; map = map__next(map)) {
705 		struct map *new = map__clone(map);
706 		if (new == NULL)
707 			goto out_unlock;
708 		map_groups__insert(mg, new);
709 	}
710 
711 	err = 0;
712 out_unlock:
713 	pthread_rwlock_unlock(&maps->lock);
714 	return err;
715 }
716 
717 static void __maps__insert(struct maps *maps, struct map *map)
718 {
719 	struct rb_node **p = &maps->entries.rb_node;
720 	struct rb_node *parent = NULL;
721 	const u64 ip = map->start;
722 	struct map *m;
723 
724 	while (*p != NULL) {
725 		parent = *p;
726 		m = rb_entry(parent, struct map, rb_node);
727 		if (ip < m->start)
728 			p = &(*p)->rb_left;
729 		else
730 			p = &(*p)->rb_right;
731 	}
732 
733 	rb_link_node(&map->rb_node, parent, p);
734 	rb_insert_color(&map->rb_node, &maps->entries);
735 	map__get(map);
736 }
737 
738 void maps__insert(struct maps *maps, struct map *map)
739 {
740 	pthread_rwlock_wrlock(&maps->lock);
741 	__maps__insert(maps, map);
742 	pthread_rwlock_unlock(&maps->lock);
743 }
744 
745 static void __maps__remove(struct maps *maps, struct map *map)
746 {
747 	rb_erase_init(&map->rb_node, &maps->entries);
748 	map__put(map);
749 }
750 
751 void maps__remove(struct maps *maps, struct map *map)
752 {
753 	pthread_rwlock_wrlock(&maps->lock);
754 	__maps__remove(maps, map);
755 	pthread_rwlock_unlock(&maps->lock);
756 }
757 
758 struct map *maps__find(struct maps *maps, u64 ip)
759 {
760 	struct rb_node **p, *parent = NULL;
761 	struct map *m;
762 
763 	pthread_rwlock_rdlock(&maps->lock);
764 
765 	p = &maps->entries.rb_node;
766 	while (*p != NULL) {
767 		parent = *p;
768 		m = rb_entry(parent, struct map, rb_node);
769 		if (ip < m->start)
770 			p = &(*p)->rb_left;
771 		else if (ip >= m->end)
772 			p = &(*p)->rb_right;
773 		else
774 			goto out;
775 	}
776 
777 	m = NULL;
778 out:
779 	pthread_rwlock_unlock(&maps->lock);
780 	return m;
781 }
782 
783 struct map *maps__first(struct maps *maps)
784 {
785 	struct rb_node *first = rb_first(&maps->entries);
786 
787 	if (first)
788 		return rb_entry(first, struct map, rb_node);
789 	return NULL;
790 }
791 
792 struct map *map__next(struct map *map)
793 {
794 	struct rb_node *next = rb_next(&map->rb_node);
795 
796 	if (next)
797 		return rb_entry(next, struct map, rb_node);
798 	return NULL;
799 }
800 
801 struct kmap *map__kmap(struct map *map)
802 {
803 	if (!map->dso || !map->dso->kernel) {
804 		pr_err("Internal error: map__kmap with a non-kernel map\n");
805 		return NULL;
806 	}
807 	return (struct kmap *)(map + 1);
808 }
809 
810 struct map_groups *map__kmaps(struct map *map)
811 {
812 	struct kmap *kmap = map__kmap(map);
813 
814 	if (!kmap || !kmap->kmaps) {
815 		pr_err("Internal error: map__kmaps with a non-kernel map\n");
816 		return NULL;
817 	}
818 	return kmap->kmaps;
819 }
820