xref: /openbmc/linux/tools/perf/util/map.c (revision 35410f86)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "symbol.h"
3 #include <assert.h>
4 #include <errno.h>
5 #include <inttypes.h>
6 #include <limits.h>
7 #include <stdlib.h>
8 #include <string.h>
9 #include <stdio.h>
10 #include <unistd.h>
11 #include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
12 #include "dso.h"
13 #include "map.h"
14 #include "map_symbol.h"
15 #include "thread.h"
16 #include "vdso.h"
17 #include "build-id.h"
18 #include "debug.h"
19 #include "machine.h"
20 #include <linux/string.h>
21 #include <linux/zalloc.h>
22 #include "srcline.h"
23 #include "namespaces.h"
24 #include "unwind.h"
25 #include "srccode.h"
26 #include "ui/ui.h"
27 
28 static void __maps__insert(struct maps *maps, struct map *map);
29 
30 static inline int is_android_lib(const char *filename)
31 {
32 	return strstarts(filename, "/data/app-lib/") ||
33 	       strstarts(filename, "/system/lib/");
34 }
35 
36 static inline bool replace_android_lib(const char *filename, char *newfilename)
37 {
38 	const char *libname;
39 	char *app_abi;
40 	size_t app_abi_length, new_length;
41 	size_t lib_length = 0;
42 
43 	libname  = strrchr(filename, '/');
44 	if (libname)
45 		lib_length = strlen(libname);
46 
47 	app_abi = getenv("APP_ABI");
48 	if (!app_abi)
49 		return false;
50 
51 	app_abi_length = strlen(app_abi);
52 
53 	if (strstarts(filename, "/data/app-lib/")) {
54 		char *apk_path;
55 
56 		if (!app_abi_length)
57 			return false;
58 
59 		new_length = 7 + app_abi_length + lib_length;
60 
61 		apk_path = getenv("APK_PATH");
62 		if (apk_path) {
63 			new_length += strlen(apk_path) + 1;
64 			if (new_length > PATH_MAX)
65 				return false;
66 			snprintf(newfilename, new_length,
67 				 "%s/libs/%s/%s", apk_path, app_abi, libname);
68 		} else {
69 			if (new_length > PATH_MAX)
70 				return false;
71 			snprintf(newfilename, new_length,
72 				 "libs/%s/%s", app_abi, libname);
73 		}
74 		return true;
75 	}
76 
77 	if (strstarts(filename, "/system/lib/")) {
78 		char *ndk, *app;
79 		const char *arch;
80 		int ndk_length, app_length;
81 
82 		ndk = getenv("NDK_ROOT");
83 		app = getenv("APP_PLATFORM");
84 
85 		if (!(ndk && app))
86 			return false;
87 
88 		ndk_length = strlen(ndk);
89 		app_length = strlen(app);
90 
91 		if (!(ndk_length && app_length && app_abi_length))
92 			return false;
93 
94 		arch = !strncmp(app_abi, "arm", 3) ? "arm" :
95 		       !strncmp(app_abi, "mips", 4) ? "mips" :
96 		       !strncmp(app_abi, "x86", 3) ? "x86" : NULL;
97 
98 		if (!arch)
99 			return false;
100 
101 		new_length = 27 + ndk_length +
102 			     app_length + lib_length
103 			   + strlen(arch);
104 
105 		if (new_length > PATH_MAX)
106 			return false;
107 		snprintf(newfilename, new_length,
108 			"%.*s/platforms/%.*s/arch-%s/usr/lib/%s",
109 			ndk_length, ndk, app_length, app, arch, libname);
110 
111 		return true;
112 	}
113 	return false;
114 }
115 
116 void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso)
117 {
118 	map->start    = start;
119 	map->end      = end;
120 	map->pgoff    = pgoff;
121 	map->reloc    = 0;
122 	map->dso      = dso__get(dso);
123 	map->map_ip   = map__map_ip;
124 	map->unmap_ip = map__unmap_ip;
125 	RB_CLEAR_NODE(&map->rb_node);
126 	map->erange_warned = false;
127 	refcount_set(&map->refcnt, 1);
128 }
129 
130 struct map *map__new(struct machine *machine, u64 start, u64 len,
131 		     u64 pgoff, struct dso_id *id,
132 		     u32 prot, u32 flags, struct build_id *bid,
133 		     char *filename, struct thread *thread)
134 {
135 	struct map *map = malloc(sizeof(*map));
136 	struct nsinfo *nsi = NULL;
137 	struct nsinfo *nnsi;
138 
139 	if (map != NULL) {
140 		char newfilename[PATH_MAX];
141 		struct dso *dso;
142 		int anon, no_dso, vdso, android;
143 
144 		android = is_android_lib(filename);
145 		anon = is_anon_memory(filename) || flags & MAP_HUGETLB;
146 		vdso = is_vdso_map(filename);
147 		no_dso = is_no_dso_memory(filename);
148 		map->prot = prot;
149 		map->flags = flags;
150 		nsi = nsinfo__get(thread->nsinfo);
151 
152 		if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {
153 			snprintf(newfilename, sizeof(newfilename),
154 				 "/tmp/perf-%d.map", nsi->pid);
155 			filename = newfilename;
156 		}
157 
158 		if (android) {
159 			if (replace_android_lib(filename, newfilename))
160 				filename = newfilename;
161 		}
162 
163 		if (vdso) {
164 			/* The vdso maps are always on the host and not the
165 			 * container.  Ensure that we don't use setns to look
166 			 * them up.
167 			 */
168 			nnsi = nsinfo__copy(nsi);
169 			if (nnsi) {
170 				nsinfo__put(nsi);
171 				nnsi->need_setns = false;
172 				nsi = nnsi;
173 			}
174 			pgoff = 0;
175 			dso = machine__findnew_vdso(machine, thread);
176 		} else
177 			dso = machine__findnew_dso_id(machine, filename, id);
178 
179 		if (dso == NULL)
180 			goto out_delete;
181 
182 		map__init(map, start, start + len, pgoff, dso);
183 
184 		if (anon || no_dso) {
185 			map->map_ip = map->unmap_ip = identity__map_ip;
186 
187 			/*
188 			 * Set memory without DSO as loaded. All map__find_*
189 			 * functions still return NULL, and we avoid the
190 			 * unnecessary map__load warning.
191 			 */
192 			if (!(prot & PROT_EXEC))
193 				dso__set_loaded(dso);
194 		}
195 
196 		nsinfo__put(dso->nsinfo);
197 		dso->nsinfo = nsi;
198 
199 		if (build_id__is_defined(bid))
200 			dso__set_build_id(dso, bid);
201 
202 		dso__put(dso);
203 	}
204 	return map;
205 out_delete:
206 	nsinfo__put(nsi);
207 	free(map);
208 	return NULL;
209 }
210 
211 /*
212  * Constructor variant for modules (where we know from /proc/modules where
213  * they are loaded) and for vmlinux, where only after we load all the
214  * symbols we'll know where it starts and ends.
215  */
216 struct map *map__new2(u64 start, struct dso *dso)
217 {
218 	struct map *map = calloc(1, (sizeof(*map) +
219 				     (dso->kernel ? sizeof(struct kmap) : 0)));
220 	if (map != NULL) {
221 		/*
222 		 * ->end will be filled after we load all the symbols
223 		 */
224 		map__init(map, start, 0, 0, dso);
225 	}
226 
227 	return map;
228 }
229 
230 bool __map__is_kernel(const struct map *map)
231 {
232 	if (!map->dso->kernel)
233 		return false;
234 	return machine__kernel_map(map__kmaps((struct map *)map)->machine) == map;
235 }
236 
237 bool __map__is_extra_kernel_map(const struct map *map)
238 {
239 	struct kmap *kmap = __map__kmap((struct map *)map);
240 
241 	return kmap && kmap->name[0];
242 }
243 
244 bool __map__is_bpf_prog(const struct map *map)
245 {
246 	const char *name;
247 
248 	if (map->dso->binary_type == DSO_BINARY_TYPE__BPF_PROG_INFO)
249 		return true;
250 
251 	/*
252 	 * If PERF_RECORD_BPF_EVENT is not included, the dso will not have
253 	 * type of DSO_BINARY_TYPE__BPF_PROG_INFO. In such cases, we can
254 	 * guess the type based on name.
255 	 */
256 	name = map->dso->short_name;
257 	return name && (strstr(name, "bpf_prog_") == name);
258 }
259 
260 bool __map__is_bpf_image(const struct map *map)
261 {
262 	const char *name;
263 
264 	if (map->dso->binary_type == DSO_BINARY_TYPE__BPF_IMAGE)
265 		return true;
266 
267 	/*
268 	 * If PERF_RECORD_KSYMBOL is not included, the dso will not have
269 	 * type of DSO_BINARY_TYPE__BPF_IMAGE. In such cases, we can
270 	 * guess the type based on name.
271 	 */
272 	name = map->dso->short_name;
273 	return name && is_bpf_image(name);
274 }
275 
276 bool __map__is_ool(const struct map *map)
277 {
278 	return map->dso && map->dso->binary_type == DSO_BINARY_TYPE__OOL;
279 }
280 
281 bool map__has_symbols(const struct map *map)
282 {
283 	return dso__has_symbols(map->dso);
284 }
285 
286 static void map__exit(struct map *map)
287 {
288 	BUG_ON(refcount_read(&map->refcnt) != 0);
289 	dso__zput(map->dso);
290 }
291 
292 void map__delete(struct map *map)
293 {
294 	map__exit(map);
295 	free(map);
296 }
297 
298 void map__put(struct map *map)
299 {
300 	if (map && refcount_dec_and_test(&map->refcnt))
301 		map__delete(map);
302 }
303 
304 void map__fixup_start(struct map *map)
305 {
306 	struct rb_root_cached *symbols = &map->dso->symbols;
307 	struct rb_node *nd = rb_first_cached(symbols);
308 	if (nd != NULL) {
309 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
310 		map->start = sym->start;
311 	}
312 }
313 
314 void map__fixup_end(struct map *map)
315 {
316 	struct rb_root_cached *symbols = &map->dso->symbols;
317 	struct rb_node *nd = rb_last(&symbols->rb_root);
318 	if (nd != NULL) {
319 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
320 		map->end = sym->end;
321 	}
322 }
323 
324 #define DSO__DELETED "(deleted)"
325 
326 int map__load(struct map *map)
327 {
328 	const char *name = map->dso->long_name;
329 	int nr;
330 
331 	if (dso__loaded(map->dso))
332 		return 0;
333 
334 	nr = dso__load(map->dso, map);
335 	if (nr < 0) {
336 		if (map->dso->has_build_id) {
337 			char sbuild_id[SBUILD_ID_SIZE];
338 
339 			build_id__sprintf(&map->dso->bid, sbuild_id);
340 			pr_debug("%s with build id %s not found", name, sbuild_id);
341 		} else
342 			pr_debug("Failed to open %s", name);
343 
344 		pr_debug(", continuing without symbols\n");
345 		return -1;
346 	} else if (nr == 0) {
347 #ifdef HAVE_LIBELF_SUPPORT
348 		const size_t len = strlen(name);
349 		const size_t real_len = len - sizeof(DSO__DELETED);
350 
351 		if (len > sizeof(DSO__DELETED) &&
352 		    strcmp(name + real_len + 1, DSO__DELETED) == 0) {
353 			pr_debug("%.*s was updated (is prelink enabled?). "
354 				"Restart the long running apps that use it!\n",
355 				   (int)real_len, name);
356 		} else {
357 			pr_debug("no symbols found in %s, maybe install a debug package?\n", name);
358 		}
359 #endif
360 		return -1;
361 	}
362 
363 	return 0;
364 }
365 
366 struct symbol *map__find_symbol(struct map *map, u64 addr)
367 {
368 	if (map__load(map) < 0)
369 		return NULL;
370 
371 	return dso__find_symbol(map->dso, addr);
372 }
373 
374 struct symbol *map__find_symbol_by_name(struct map *map, const char *name)
375 {
376 	if (map__load(map) < 0)
377 		return NULL;
378 
379 	if (!dso__sorted_by_name(map->dso))
380 		dso__sort_by_name(map->dso);
381 
382 	return dso__find_symbol_by_name(map->dso, name);
383 }
384 
385 struct map *map__clone(struct map *from)
386 {
387 	size_t size = sizeof(struct map);
388 	struct map *map;
389 
390 	if (from->dso && from->dso->kernel)
391 		size += sizeof(struct kmap);
392 
393 	map = memdup(from, size);
394 	if (map != NULL) {
395 		refcount_set(&map->refcnt, 1);
396 		RB_CLEAR_NODE(&map->rb_node);
397 		dso__get(map->dso);
398 	}
399 
400 	return map;
401 }
402 
403 size_t map__fprintf(struct map *map, FILE *fp)
404 {
405 	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
406 		       map->start, map->end, map->pgoff, map->dso->name);
407 }
408 
409 size_t map__fprintf_dsoname(struct map *map, FILE *fp)
410 {
411 	char buf[symbol_conf.pad_output_len_dso + 1];
412 	const char *dsoname = "[unknown]";
413 
414 	if (map && map->dso) {
415 		if (symbol_conf.show_kernel_path && map->dso->long_name)
416 			dsoname = map->dso->long_name;
417 		else
418 			dsoname = map->dso->name;
419 	}
420 
421 	if (symbol_conf.pad_output_len_dso) {
422 		scnprintf_pad(buf, symbol_conf.pad_output_len_dso, "%s", dsoname);
423 		dsoname = buf;
424 	}
425 
426 	return fprintf(fp, "%s", dsoname);
427 }
428 
429 char *map__srcline(struct map *map, u64 addr, struct symbol *sym)
430 {
431 	if (map == NULL)
432 		return SRCLINE_UNKNOWN;
433 	return get_srcline(map->dso, map__rip_2objdump(map, addr), sym, true, true, addr);
434 }
435 
436 int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
437 			 FILE *fp)
438 {
439 	int ret = 0;
440 
441 	if (map && map->dso) {
442 		char *srcline = map__srcline(map, addr, NULL);
443 		if (strncmp(srcline, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0)
444 			ret = fprintf(fp, "%s%s", prefix, srcline);
445 		free_srcline(srcline);
446 	}
447 	return ret;
448 }
449 
450 void srccode_state_free(struct srccode_state *state)
451 {
452 	zfree(&state->srcfile);
453 	state->line = 0;
454 }
455 
456 /**
457  * map__rip_2objdump - convert symbol start address to objdump address.
458  * @map: memory map
459  * @rip: symbol start address
460  *
461  * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
462  * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
463  * relative to section start.
464  *
465  * Return: Address suitable for passing to "objdump --start-address="
466  */
467 u64 map__rip_2objdump(struct map *map, u64 rip)
468 {
469 	struct kmap *kmap = __map__kmap(map);
470 
471 	/*
472 	 * vmlinux does not have program headers for PTI entry trampolines and
473 	 * kcore may not either. However the trampoline object code is on the
474 	 * main kernel map, so just use that instead.
475 	 */
476 	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps && kmap->kmaps->machine) {
477 		struct map *kernel_map = machine__kernel_map(kmap->kmaps->machine);
478 
479 		if (kernel_map)
480 			map = kernel_map;
481 	}
482 
483 	if (!map->dso->adjust_symbols)
484 		return rip;
485 
486 	if (map->dso->rel)
487 		return rip - map->pgoff;
488 
489 	/*
490 	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
491 	 * but all kernel modules are ET_REL, so won't get here.
492 	 */
493 	if (map->dso->kernel == DSO_SPACE__USER)
494 		return rip + map->dso->text_offset;
495 
496 	return map->unmap_ip(map, rip) - map->reloc;
497 }
498 
499 /**
500  * map__objdump_2mem - convert objdump address to a memory address.
501  * @map: memory map
502  * @ip: objdump address
503  *
504  * Closely related to map__rip_2objdump(), this function takes an address from
505  * objdump and converts it to a memory address.  Note this assumes that @map
506  * contains the address.  To be sure the result is valid, check it forwards
507  * e.g. map__rip_2objdump(map->map_ip(map, map__objdump_2mem(map, ip))) == ip
508  *
509  * Return: Memory address.
510  */
511 u64 map__objdump_2mem(struct map *map, u64 ip)
512 {
513 	if (!map->dso->adjust_symbols)
514 		return map->unmap_ip(map, ip);
515 
516 	if (map->dso->rel)
517 		return map->unmap_ip(map, ip + map->pgoff);
518 
519 	/*
520 	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
521 	 * but all kernel modules are ET_REL, so won't get here.
522 	 */
523 	if (map->dso->kernel == DSO_SPACE__USER)
524 		return map->unmap_ip(map, ip - map->dso->text_offset);
525 
526 	return ip + map->reloc;
527 }
528 
529 void maps__init(struct maps *maps, struct machine *machine)
530 {
531 	maps->entries = RB_ROOT;
532 	init_rwsem(&maps->lock);
533 	maps->machine = machine;
534 	maps->last_search_by_name = NULL;
535 	maps->nr_maps = 0;
536 	maps->maps_by_name = NULL;
537 	refcount_set(&maps->refcnt, 1);
538 }
539 
540 static void __maps__free_maps_by_name(struct maps *maps)
541 {
542 	/*
543 	 * Free everything to try to do it from the rbtree in the next search
544 	 */
545 	zfree(&maps->maps_by_name);
546 	maps->nr_maps_allocated = 0;
547 }
548 
549 void maps__insert(struct maps *maps, struct map *map)
550 {
551 	down_write(&maps->lock);
552 	__maps__insert(maps, map);
553 	++maps->nr_maps;
554 
555 	if (map->dso && map->dso->kernel) {
556 		struct kmap *kmap = map__kmap(map);
557 
558 		if (kmap)
559 			kmap->kmaps = maps;
560 		else
561 			pr_err("Internal error: kernel dso with non kernel map\n");
562 	}
563 
564 
565 	/*
566 	 * If we already performed some search by name, then we need to add the just
567 	 * inserted map and resort.
568 	 */
569 	if (maps->maps_by_name) {
570 		if (maps->nr_maps > maps->nr_maps_allocated) {
571 			int nr_allocate = maps->nr_maps * 2;
572 			struct map **maps_by_name = realloc(maps->maps_by_name, nr_allocate * sizeof(map));
573 
574 			if (maps_by_name == NULL) {
575 				__maps__free_maps_by_name(maps);
576 				up_write(&maps->lock);
577 				return;
578 			}
579 
580 			maps->maps_by_name = maps_by_name;
581 			maps->nr_maps_allocated = nr_allocate;
582 		}
583 		maps->maps_by_name[maps->nr_maps - 1] = map;
584 		__maps__sort_by_name(maps);
585 	}
586 	up_write(&maps->lock);
587 }
588 
589 static void __maps__remove(struct maps *maps, struct map *map)
590 {
591 	rb_erase_init(&map->rb_node, &maps->entries);
592 	map__put(map);
593 }
594 
595 void maps__remove(struct maps *maps, struct map *map)
596 {
597 	down_write(&maps->lock);
598 	if (maps->last_search_by_name == map)
599 		maps->last_search_by_name = NULL;
600 
601 	__maps__remove(maps, map);
602 	--maps->nr_maps;
603 	if (maps->maps_by_name)
604 		__maps__free_maps_by_name(maps);
605 	up_write(&maps->lock);
606 }
607 
608 static void __maps__purge(struct maps *maps)
609 {
610 	struct map *pos, *next;
611 
612 	maps__for_each_entry_safe(maps, pos, next) {
613 		rb_erase_init(&pos->rb_node,  &maps->entries);
614 		map__put(pos);
615 	}
616 }
617 
618 void maps__exit(struct maps *maps)
619 {
620 	down_write(&maps->lock);
621 	__maps__purge(maps);
622 	up_write(&maps->lock);
623 }
624 
625 bool maps__empty(struct maps *maps)
626 {
627 	return !maps__first(maps);
628 }
629 
630 struct maps *maps__new(struct machine *machine)
631 {
632 	struct maps *maps = zalloc(sizeof(*maps));
633 
634 	if (maps != NULL)
635 		maps__init(maps, machine);
636 
637 	return maps;
638 }
639 
640 void maps__delete(struct maps *maps)
641 {
642 	maps__exit(maps);
643 	unwind__finish_access(maps);
644 	free(maps);
645 }
646 
647 void maps__put(struct maps *maps)
648 {
649 	if (maps && refcount_dec_and_test(&maps->refcnt))
650 		maps__delete(maps);
651 }
652 
653 struct symbol *maps__find_symbol(struct maps *maps, u64 addr, struct map **mapp)
654 {
655 	struct map *map = maps__find(maps, addr);
656 
657 	/* Ensure map is loaded before using map->map_ip */
658 	if (map != NULL && map__load(map) >= 0) {
659 		if (mapp != NULL)
660 			*mapp = map;
661 		return map__find_symbol(map, map->map_ip(map, addr));
662 	}
663 
664 	return NULL;
665 }
666 
667 static bool map__contains_symbol(struct map *map, struct symbol *sym)
668 {
669 	u64 ip = map->unmap_ip(map, sym->start);
670 
671 	return ip >= map->start && ip < map->end;
672 }
673 
674 struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name, struct map **mapp)
675 {
676 	struct symbol *sym;
677 	struct map *pos;
678 
679 	down_read(&maps->lock);
680 
681 	maps__for_each_entry(maps, pos) {
682 		sym = map__find_symbol_by_name(pos, name);
683 
684 		if (sym == NULL)
685 			continue;
686 		if (!map__contains_symbol(pos, sym)) {
687 			sym = NULL;
688 			continue;
689 		}
690 		if (mapp != NULL)
691 			*mapp = pos;
692 		goto out;
693 	}
694 
695 	sym = NULL;
696 out:
697 	up_read(&maps->lock);
698 	return sym;
699 }
700 
701 int maps__find_ams(struct maps *maps, struct addr_map_symbol *ams)
702 {
703 	if (ams->addr < ams->ms.map->start || ams->addr >= ams->ms.map->end) {
704 		if (maps == NULL)
705 			return -1;
706 		ams->ms.map = maps__find(maps, ams->addr);
707 		if (ams->ms.map == NULL)
708 			return -1;
709 	}
710 
711 	ams->al_addr = ams->ms.map->map_ip(ams->ms.map, ams->addr);
712 	ams->ms.sym = map__find_symbol(ams->ms.map, ams->al_addr);
713 
714 	return ams->ms.sym ? 0 : -1;
715 }
716 
717 size_t maps__fprintf(struct maps *maps, FILE *fp)
718 {
719 	size_t printed = 0;
720 	struct map *pos;
721 
722 	down_read(&maps->lock);
723 
724 	maps__for_each_entry(maps, pos) {
725 		printed += fprintf(fp, "Map:");
726 		printed += map__fprintf(pos, fp);
727 		if (verbose > 2) {
728 			printed += dso__fprintf(pos->dso, fp);
729 			printed += fprintf(fp, "--\n");
730 		}
731 	}
732 
733 	up_read(&maps->lock);
734 
735 	return printed;
736 }
737 
738 int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
739 {
740 	struct rb_root *root;
741 	struct rb_node *next, *first;
742 	int err = 0;
743 
744 	down_write(&maps->lock);
745 
746 	root = &maps->entries;
747 
748 	/*
749 	 * Find first map where end > map->start.
750 	 * Same as find_vma() in kernel.
751 	 */
752 	next = root->rb_node;
753 	first = NULL;
754 	while (next) {
755 		struct map *pos = rb_entry(next, struct map, rb_node);
756 
757 		if (pos->end > map->start) {
758 			first = next;
759 			if (pos->start <= map->start)
760 				break;
761 			next = next->rb_left;
762 		} else
763 			next = next->rb_right;
764 	}
765 
766 	next = first;
767 	while (next) {
768 		struct map *pos = rb_entry(next, struct map, rb_node);
769 		next = rb_next(&pos->rb_node);
770 
771 		/*
772 		 * Stop if current map starts after map->end.
773 		 * Maps are ordered by start: next will not overlap for sure.
774 		 */
775 		if (pos->start >= map->end)
776 			break;
777 
778 		if (verbose >= 2) {
779 
780 			if (use_browser) {
781 				pr_debug("overlapping maps in %s (disable tui for more info)\n",
782 					   map->dso->name);
783 			} else {
784 				fputs("overlapping maps:\n", fp);
785 				map__fprintf(map, fp);
786 				map__fprintf(pos, fp);
787 			}
788 		}
789 
790 		rb_erase_init(&pos->rb_node, root);
791 		/*
792 		 * Now check if we need to create new maps for areas not
793 		 * overlapped by the new map:
794 		 */
795 		if (map->start > pos->start) {
796 			struct map *before = map__clone(pos);
797 
798 			if (before == NULL) {
799 				err = -ENOMEM;
800 				goto put_map;
801 			}
802 
803 			before->end = map->start;
804 			__maps__insert(maps, before);
805 			if (verbose >= 2 && !use_browser)
806 				map__fprintf(before, fp);
807 			map__put(before);
808 		}
809 
810 		if (map->end < pos->end) {
811 			struct map *after = map__clone(pos);
812 
813 			if (after == NULL) {
814 				err = -ENOMEM;
815 				goto put_map;
816 			}
817 
818 			after->start = map->end;
819 			after->pgoff += map->end - pos->start;
820 			assert(pos->map_ip(pos, map->end) == after->map_ip(after, map->end));
821 			__maps__insert(maps, after);
822 			if (verbose >= 2 && !use_browser)
823 				map__fprintf(after, fp);
824 			map__put(after);
825 		}
826 put_map:
827 		map__put(pos);
828 
829 		if (err)
830 			goto out;
831 	}
832 
833 	err = 0;
834 out:
835 	up_write(&maps->lock);
836 	return err;
837 }
838 
839 /*
840  * XXX This should not really _copy_ te maps, but refcount them.
841  */
842 int maps__clone(struct thread *thread, struct maps *parent)
843 {
844 	struct maps *maps = thread->maps;
845 	int err;
846 	struct map *map;
847 
848 	down_read(&parent->lock);
849 
850 	maps__for_each_entry(parent, map) {
851 		struct map *new = map__clone(map);
852 
853 		if (new == NULL) {
854 			err = -ENOMEM;
855 			goto out_unlock;
856 		}
857 
858 		err = unwind__prepare_access(maps, new, NULL);
859 		if (err)
860 			goto out_unlock;
861 
862 		maps__insert(maps, new);
863 		map__put(new);
864 	}
865 
866 	err = 0;
867 out_unlock:
868 	up_read(&parent->lock);
869 	return err;
870 }
871 
872 static void __maps__insert(struct maps *maps, struct map *map)
873 {
874 	struct rb_node **p = &maps->entries.rb_node;
875 	struct rb_node *parent = NULL;
876 	const u64 ip = map->start;
877 	struct map *m;
878 
879 	while (*p != NULL) {
880 		parent = *p;
881 		m = rb_entry(parent, struct map, rb_node);
882 		if (ip < m->start)
883 			p = &(*p)->rb_left;
884 		else
885 			p = &(*p)->rb_right;
886 	}
887 
888 	rb_link_node(&map->rb_node, parent, p);
889 	rb_insert_color(&map->rb_node, &maps->entries);
890 	map__get(map);
891 }
892 
893 struct map *maps__find(struct maps *maps, u64 ip)
894 {
895 	struct rb_node *p;
896 	struct map *m;
897 
898 	down_read(&maps->lock);
899 
900 	p = maps->entries.rb_node;
901 	while (p != NULL) {
902 		m = rb_entry(p, struct map, rb_node);
903 		if (ip < m->start)
904 			p = p->rb_left;
905 		else if (ip >= m->end)
906 			p = p->rb_right;
907 		else
908 			goto out;
909 	}
910 
911 	m = NULL;
912 out:
913 	up_read(&maps->lock);
914 	return m;
915 }
916 
917 struct map *maps__first(struct maps *maps)
918 {
919 	struct rb_node *first = rb_first(&maps->entries);
920 
921 	if (first)
922 		return rb_entry(first, struct map, rb_node);
923 	return NULL;
924 }
925 
926 static struct map *__map__next(struct map *map)
927 {
928 	struct rb_node *next = rb_next(&map->rb_node);
929 
930 	if (next)
931 		return rb_entry(next, struct map, rb_node);
932 	return NULL;
933 }
934 
935 struct map *map__next(struct map *map)
936 {
937 	return map ? __map__next(map) : NULL;
938 }
939 
940 struct kmap *__map__kmap(struct map *map)
941 {
942 	if (!map->dso || !map->dso->kernel)
943 		return NULL;
944 	return (struct kmap *)(map + 1);
945 }
946 
947 struct kmap *map__kmap(struct map *map)
948 {
949 	struct kmap *kmap = __map__kmap(map);
950 
951 	if (!kmap)
952 		pr_err("Internal error: map__kmap with a non-kernel map\n");
953 	return kmap;
954 }
955 
956 struct maps *map__kmaps(struct map *map)
957 {
958 	struct kmap *kmap = map__kmap(map);
959 
960 	if (!kmap || !kmap->kmaps) {
961 		pr_err("Internal error: map__kmaps with a non-kernel map\n");
962 		return NULL;
963 	}
964 	return kmap->kmaps;
965 }
966