xref: /openbmc/linux/tools/perf/util/map.c (revision 9a8f3203)
1 // SPDX-License-Identifier: GPL-2.0
2 #include "symbol.h"
3 #include <errno.h>
4 #include <inttypes.h>
5 #include <limits.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <stdio.h>
9 #include <unistd.h>
10 #include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
11 #include "map.h"
12 #include "thread.h"
13 #include "vdso.h"
14 #include "build-id.h"
15 #include "util.h"
16 #include "debug.h"
17 #include "machine.h"
18 #include <linux/string.h>
19 #include "srcline.h"
20 #include "namespaces.h"
21 #include "unwind.h"
22 #include "srccode.h"
23 
24 static void __maps__insert(struct maps *maps, struct map *map);
25 static void __maps__insert_name(struct maps *maps, struct map *map);
26 
27 static inline int is_anon_memory(const char *filename, u32 flags)
28 {
29 	return flags & MAP_HUGETLB ||
30 	       !strcmp(filename, "//anon") ||
31 	       !strncmp(filename, "/dev/zero", sizeof("/dev/zero") - 1) ||
32 	       !strncmp(filename, "/anon_hugepage", sizeof("/anon_hugepage") - 1);
33 }
34 
35 static inline int is_no_dso_memory(const char *filename)
36 {
37 	return !strncmp(filename, "[stack", 6) ||
38 	       !strncmp(filename, "/SYSV",5)   ||
39 	       !strcmp(filename, "[heap]");
40 }
41 
42 static inline int is_android_lib(const char *filename)
43 {
44 	return !strncmp(filename, "/data/app-lib", 13) ||
45 	       !strncmp(filename, "/system/lib", 11);
46 }
47 
48 static inline bool replace_android_lib(const char *filename, char *newfilename)
49 {
50 	const char *libname;
51 	char *app_abi;
52 	size_t app_abi_length, new_length;
53 	size_t lib_length = 0;
54 
55 	libname  = strrchr(filename, '/');
56 	if (libname)
57 		lib_length = strlen(libname);
58 
59 	app_abi = getenv("APP_ABI");
60 	if (!app_abi)
61 		return false;
62 
63 	app_abi_length = strlen(app_abi);
64 
65 	if (!strncmp(filename, "/data/app-lib", 13)) {
66 		char *apk_path;
67 
68 		if (!app_abi_length)
69 			return false;
70 
71 		new_length = 7 + app_abi_length + lib_length;
72 
73 		apk_path = getenv("APK_PATH");
74 		if (apk_path) {
75 			new_length += strlen(apk_path) + 1;
76 			if (new_length > PATH_MAX)
77 				return false;
78 			snprintf(newfilename, new_length,
79 				 "%s/libs/%s/%s", apk_path, app_abi, libname);
80 		} else {
81 			if (new_length > PATH_MAX)
82 				return false;
83 			snprintf(newfilename, new_length,
84 				 "libs/%s/%s", app_abi, libname);
85 		}
86 		return true;
87 	}
88 
89 	if (!strncmp(filename, "/system/lib/", 11)) {
90 		char *ndk, *app;
91 		const char *arch;
92 		size_t ndk_length;
93 		size_t app_length;
94 
95 		ndk = getenv("NDK_ROOT");
96 		app = getenv("APP_PLATFORM");
97 
98 		if (!(ndk && app))
99 			return false;
100 
101 		ndk_length = strlen(ndk);
102 		app_length = strlen(app);
103 
104 		if (!(ndk_length && app_length && app_abi_length))
105 			return false;
106 
107 		arch = !strncmp(app_abi, "arm", 3) ? "arm" :
108 		       !strncmp(app_abi, "mips", 4) ? "mips" :
109 		       !strncmp(app_abi, "x86", 3) ? "x86" : NULL;
110 
111 		if (!arch)
112 			return false;
113 
114 		new_length = 27 + ndk_length +
115 			     app_length + lib_length
116 			   + strlen(arch);
117 
118 		if (new_length > PATH_MAX)
119 			return false;
120 		snprintf(newfilename, new_length,
121 			"%s/platforms/%s/arch-%s/usr/lib/%s",
122 			ndk, app, arch, libname);
123 
124 		return true;
125 	}
126 	return false;
127 }
128 
129 void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso)
130 {
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 	refcount_set(&map->refcnt, 1);
142 }
143 
144 struct map *map__new(struct machine *machine, u64 start, u64 len,
145 		     u64 pgoff, u32 d_maj, u32 d_min, u64 ino,
146 		     u64 ino_gen, u32 prot, u32 flags, char *filename,
147 		     struct thread *thread)
148 {
149 	struct map *map = malloc(sizeof(*map));
150 	struct nsinfo *nsi = NULL;
151 	struct nsinfo *nnsi;
152 
153 	if (map != NULL) {
154 		char newfilename[PATH_MAX];
155 		struct dso *dso;
156 		int anon, no_dso, vdso, android;
157 
158 		android = is_android_lib(filename);
159 		anon = is_anon_memory(filename, flags);
160 		vdso = is_vdso_map(filename);
161 		no_dso = is_no_dso_memory(filename);
162 
163 		map->maj = d_maj;
164 		map->min = d_min;
165 		map->ino = ino;
166 		map->ino_generation = ino_gen;
167 		map->prot = prot;
168 		map->flags = flags;
169 		nsi = nsinfo__get(thread->nsinfo);
170 
171 		if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {
172 			snprintf(newfilename, sizeof(newfilename),
173 				 "/tmp/perf-%d.map", nsi->pid);
174 			filename = newfilename;
175 		}
176 
177 		if (android) {
178 			if (replace_android_lib(filename, newfilename))
179 				filename = newfilename;
180 		}
181 
182 		if (vdso) {
183 			/* The vdso maps are always on the host and not the
184 			 * container.  Ensure that we don't use setns to look
185 			 * them up.
186 			 */
187 			nnsi = nsinfo__copy(nsi);
188 			if (nnsi) {
189 				nsinfo__put(nsi);
190 				nnsi->need_setns = false;
191 				nsi = nnsi;
192 			}
193 			pgoff = 0;
194 			dso = machine__findnew_vdso(machine, thread);
195 		} else
196 			dso = machine__findnew_dso(machine, filename);
197 
198 		if (dso == NULL)
199 			goto out_delete;
200 
201 		map__init(map, start, start + len, pgoff, dso);
202 
203 		if (anon || no_dso) {
204 			map->map_ip = map->unmap_ip = identity__map_ip;
205 
206 			/*
207 			 * Set memory without DSO as loaded. All map__find_*
208 			 * functions still return NULL, and we avoid the
209 			 * unnecessary map__load warning.
210 			 */
211 			if (!(prot & PROT_EXEC))
212 				dso__set_loaded(dso);
213 		}
214 		dso->nsinfo = nsi;
215 		dso__put(dso);
216 	}
217 	return map;
218 out_delete:
219 	nsinfo__put(nsi);
220 	free(map);
221 	return NULL;
222 }
223 
224 /*
225  * Constructor variant for modules (where we know from /proc/modules where
226  * they are loaded) and for vmlinux, where only after we load all the
227  * symbols we'll know where it starts and ends.
228  */
229 struct map *map__new2(u64 start, struct dso *dso)
230 {
231 	struct map *map = calloc(1, (sizeof(*map) +
232 				     (dso->kernel ? sizeof(struct kmap) : 0)));
233 	if (map != NULL) {
234 		/*
235 		 * ->end will be filled after we load all the symbols
236 		 */
237 		map__init(map, start, 0, 0, dso);
238 	}
239 
240 	return map;
241 }
242 
243 /*
244  * Use this and __map__is_kmodule() for map instances that are in
245  * machine->kmaps, and thus have map->groups->machine all properly set, to
246  * disambiguate between the kernel and modules.
247  *
248  * When the need arises, introduce map__is_{kernel,kmodule)() that
249  * checks (map->groups != NULL && map->groups->machine != NULL &&
250  * map->dso->kernel) before calling __map__is_{kernel,kmodule}())
251  */
252 bool __map__is_kernel(const struct map *map)
253 {
254 	return machine__kernel_map(map->groups->machine) == map;
255 }
256 
257 bool __map__is_extra_kernel_map(const struct map *map)
258 {
259 	struct kmap *kmap = __map__kmap((struct map *)map);
260 
261 	return kmap && kmap->name[0];
262 }
263 
264 bool map__has_symbols(const struct map *map)
265 {
266 	return dso__has_symbols(map->dso);
267 }
268 
269 static void map__exit(struct map *map)
270 {
271 	BUG_ON(!RB_EMPTY_NODE(&map->rb_node));
272 	dso__zput(map->dso);
273 }
274 
275 void map__delete(struct map *map)
276 {
277 	map__exit(map);
278 	free(map);
279 }
280 
281 void map__put(struct map *map)
282 {
283 	if (map && refcount_dec_and_test(&map->refcnt))
284 		map__delete(map);
285 }
286 
287 void map__fixup_start(struct map *map)
288 {
289 	struct rb_root_cached *symbols = &map->dso->symbols;
290 	struct rb_node *nd = rb_first_cached(symbols);
291 	if (nd != NULL) {
292 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
293 		map->start = sym->start;
294 	}
295 }
296 
297 void map__fixup_end(struct map *map)
298 {
299 	struct rb_root_cached *symbols = &map->dso->symbols;
300 	struct rb_node *nd = rb_last(&symbols->rb_root);
301 	if (nd != NULL) {
302 		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
303 		map->end = sym->end;
304 	}
305 }
306 
307 #define DSO__DELETED "(deleted)"
308 
309 int map__load(struct map *map)
310 {
311 	const char *name = map->dso->long_name;
312 	int nr;
313 
314 	if (dso__loaded(map->dso))
315 		return 0;
316 
317 	nr = dso__load(map->dso, map);
318 	if (nr < 0) {
319 		if (map->dso->has_build_id) {
320 			char sbuild_id[SBUILD_ID_SIZE];
321 
322 			build_id__sprintf(map->dso->build_id,
323 					  sizeof(map->dso->build_id),
324 					  sbuild_id);
325 			pr_debug("%s with build id %s not found", name, sbuild_id);
326 		} else
327 			pr_debug("Failed to open %s", name);
328 
329 		pr_debug(", continuing without symbols\n");
330 		return -1;
331 	} else if (nr == 0) {
332 #ifdef HAVE_LIBELF_SUPPORT
333 		const size_t len = strlen(name);
334 		const size_t real_len = len - sizeof(DSO__DELETED);
335 
336 		if (len > sizeof(DSO__DELETED) &&
337 		    strcmp(name + real_len + 1, DSO__DELETED) == 0) {
338 			pr_debug("%.*s was updated (is prelink enabled?). "
339 				"Restart the long running apps that use it!\n",
340 				   (int)real_len, name);
341 		} else {
342 			pr_debug("no symbols found in %s, maybe install a debug package?\n", name);
343 		}
344 #endif
345 		return -1;
346 	}
347 
348 	return 0;
349 }
350 
351 struct symbol *map__find_symbol(struct map *map, u64 addr)
352 {
353 	if (map__load(map) < 0)
354 		return NULL;
355 
356 	return dso__find_symbol(map->dso, addr);
357 }
358 
359 struct symbol *map__find_symbol_by_name(struct map *map, const char *name)
360 {
361 	if (map__load(map) < 0)
362 		return NULL;
363 
364 	if (!dso__sorted_by_name(map->dso))
365 		dso__sort_by_name(map->dso);
366 
367 	return dso__find_symbol_by_name(map->dso, name);
368 }
369 
370 struct map *map__clone(struct map *from)
371 {
372 	struct map *map = memdup(from, sizeof(*map));
373 
374 	if (map != NULL) {
375 		refcount_set(&map->refcnt, 1);
376 		RB_CLEAR_NODE(&map->rb_node);
377 		dso__get(map->dso);
378 		map->groups = NULL;
379 	}
380 
381 	return map;
382 }
383 
384 size_t map__fprintf(struct map *map, FILE *fp)
385 {
386 	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
387 		       map->start, map->end, map->pgoff, map->dso->name);
388 }
389 
390 size_t map__fprintf_dsoname(struct map *map, FILE *fp)
391 {
392 	const char *dsoname = "[unknown]";
393 
394 	if (map && map->dso) {
395 		if (symbol_conf.show_kernel_path && map->dso->long_name)
396 			dsoname = map->dso->long_name;
397 		else
398 			dsoname = map->dso->name;
399 	}
400 
401 	return fprintf(fp, "%s", dsoname);
402 }
403 
404 char *map__srcline(struct map *map, u64 addr, struct symbol *sym)
405 {
406 	if (map == NULL)
407 		return SRCLINE_UNKNOWN;
408 	return get_srcline(map->dso, map__rip_2objdump(map, addr), sym, true, true, addr);
409 }
410 
411 int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
412 			 FILE *fp)
413 {
414 	int ret = 0;
415 
416 	if (map && map->dso) {
417 		char *srcline = map__srcline(map, addr, NULL);
418 		if (srcline != SRCLINE_UNKNOWN)
419 			ret = fprintf(fp, "%s%s", prefix, srcline);
420 		free_srcline(srcline);
421 	}
422 	return ret;
423 }
424 
425 int map__fprintf_srccode(struct map *map, u64 addr,
426 			 FILE *fp,
427 			 struct srccode_state *state)
428 {
429 	char *srcfile;
430 	int ret = 0;
431 	unsigned line;
432 	int len;
433 	char *srccode;
434 
435 	if (!map || !map->dso)
436 		return 0;
437 	srcfile = get_srcline_split(map->dso,
438 				    map__rip_2objdump(map, addr),
439 				    &line);
440 	if (!srcfile)
441 		return 0;
442 
443 	/* Avoid redundant printing */
444 	if (state &&
445 	    state->srcfile &&
446 	    !strcmp(state->srcfile, srcfile) &&
447 	    state->line == line) {
448 		free(srcfile);
449 		return 0;
450 	}
451 
452 	srccode = find_sourceline(srcfile, line, &len);
453 	if (!srccode)
454 		goto out_free_line;
455 
456 	ret = fprintf(fp, "|%-8d %.*s", line, len, srccode);
457 	state->srcfile = srcfile;
458 	state->line = line;
459 	return ret;
460 
461 out_free_line:
462 	free(srcfile);
463 	return ret;
464 }
465 
466 
467 void srccode_state_free(struct srccode_state *state)
468 {
469 	zfree(&state->srcfile);
470 	state->line = 0;
471 }
472 
473 /**
474  * map__rip_2objdump - convert symbol start address to objdump address.
475  * @map: memory map
476  * @rip: symbol start address
477  *
478  * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
479  * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
480  * relative to section start.
481  *
482  * Return: Address suitable for passing to "objdump --start-address="
483  */
484 u64 map__rip_2objdump(struct map *map, u64 rip)
485 {
486 	struct kmap *kmap = __map__kmap(map);
487 
488 	/*
489 	 * vmlinux does not have program headers for PTI entry trampolines and
490 	 * kcore may not either. However the trampoline object code is on the
491 	 * main kernel map, so just use that instead.
492 	 */
493 	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps && kmap->kmaps->machine) {
494 		struct map *kernel_map = machine__kernel_map(kmap->kmaps->machine);
495 
496 		if (kernel_map)
497 			map = kernel_map;
498 	}
499 
500 	if (!map->dso->adjust_symbols)
501 		return rip;
502 
503 	if (map->dso->rel)
504 		return rip - map->pgoff;
505 
506 	/*
507 	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
508 	 * but all kernel modules are ET_REL, so won't get here.
509 	 */
510 	if (map->dso->kernel == DSO_TYPE_USER)
511 		return rip + map->dso->text_offset;
512 
513 	return map->unmap_ip(map, rip) - map->reloc;
514 }
515 
516 /**
517  * map__objdump_2mem - convert objdump address to a memory address.
518  * @map: memory map
519  * @ip: objdump address
520  *
521  * Closely related to map__rip_2objdump(), this function takes an address from
522  * objdump and converts it to a memory address.  Note this assumes that @map
523  * contains the address.  To be sure the result is valid, check it forwards
524  * e.g. map__rip_2objdump(map->map_ip(map, map__objdump_2mem(map, ip))) == ip
525  *
526  * Return: Memory address.
527  */
528 u64 map__objdump_2mem(struct map *map, u64 ip)
529 {
530 	if (!map->dso->adjust_symbols)
531 		return map->unmap_ip(map, ip);
532 
533 	if (map->dso->rel)
534 		return map->unmap_ip(map, ip + map->pgoff);
535 
536 	/*
537 	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
538 	 * but all kernel modules are ET_REL, so won't get here.
539 	 */
540 	if (map->dso->kernel == DSO_TYPE_USER)
541 		return map->unmap_ip(map, ip - map->dso->text_offset);
542 
543 	return ip + map->reloc;
544 }
545 
546 static void maps__init(struct maps *maps)
547 {
548 	maps->entries = RB_ROOT;
549 	maps->names = RB_ROOT;
550 	init_rwsem(&maps->lock);
551 }
552 
553 void map_groups__init(struct map_groups *mg, struct machine *machine)
554 {
555 	maps__init(&mg->maps);
556 	mg->machine = machine;
557 	refcount_set(&mg->refcnt, 1);
558 }
559 
560 void map_groups__insert(struct map_groups *mg, struct map *map)
561 {
562 	maps__insert(&mg->maps, map);
563 	map->groups = mg;
564 }
565 
566 static void __maps__purge(struct maps *maps)
567 {
568 	struct rb_root *root = &maps->entries;
569 	struct rb_node *next = rb_first(root);
570 
571 	while (next) {
572 		struct map *pos = rb_entry(next, struct map, rb_node);
573 
574 		next = rb_next(&pos->rb_node);
575 		rb_erase_init(&pos->rb_node, root);
576 		map__put(pos);
577 	}
578 }
579 
580 static void __maps__purge_names(struct maps *maps)
581 {
582 	struct rb_root *root = &maps->names;
583 	struct rb_node *next = rb_first(root);
584 
585 	while (next) {
586 		struct map *pos = rb_entry(next, struct map, rb_node_name);
587 
588 		next = rb_next(&pos->rb_node_name);
589 		rb_erase_init(&pos->rb_node_name, root);
590 		map__put(pos);
591 	}
592 }
593 
594 static void maps__exit(struct maps *maps)
595 {
596 	down_write(&maps->lock);
597 	__maps__purge(maps);
598 	__maps__purge_names(maps);
599 	up_write(&maps->lock);
600 }
601 
602 void map_groups__exit(struct map_groups *mg)
603 {
604 	maps__exit(&mg->maps);
605 }
606 
607 bool map_groups__empty(struct map_groups *mg)
608 {
609 	return !maps__first(&mg->maps);
610 }
611 
612 struct map_groups *map_groups__new(struct machine *machine)
613 {
614 	struct map_groups *mg = malloc(sizeof(*mg));
615 
616 	if (mg != NULL)
617 		map_groups__init(mg, machine);
618 
619 	return mg;
620 }
621 
622 void map_groups__delete(struct map_groups *mg)
623 {
624 	map_groups__exit(mg);
625 	free(mg);
626 }
627 
628 void map_groups__put(struct map_groups *mg)
629 {
630 	if (mg && refcount_dec_and_test(&mg->refcnt))
631 		map_groups__delete(mg);
632 }
633 
634 struct symbol *map_groups__find_symbol(struct map_groups *mg,
635 				       u64 addr, struct map **mapp)
636 {
637 	struct map *map = map_groups__find(mg, addr);
638 
639 	/* Ensure map is loaded before using map->map_ip */
640 	if (map != NULL && map__load(map) >= 0) {
641 		if (mapp != NULL)
642 			*mapp = map;
643 		return map__find_symbol(map, map->map_ip(map, addr));
644 	}
645 
646 	return NULL;
647 }
648 
649 static bool map__contains_symbol(struct map *map, struct symbol *sym)
650 {
651 	u64 ip = map->unmap_ip(map, sym->start);
652 
653 	return ip >= map->start && ip < map->end;
654 }
655 
656 struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name,
657 					 struct map **mapp)
658 {
659 	struct symbol *sym;
660 	struct rb_node *nd;
661 
662 	down_read(&maps->lock);
663 
664 	for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
665 		struct map *pos = rb_entry(nd, struct map, rb_node);
666 
667 		sym = map__find_symbol_by_name(pos, name);
668 
669 		if (sym == NULL)
670 			continue;
671 		if (!map__contains_symbol(pos, sym)) {
672 			sym = NULL;
673 			continue;
674 		}
675 		if (mapp != NULL)
676 			*mapp = pos;
677 		goto out;
678 	}
679 
680 	sym = NULL;
681 out:
682 	up_read(&maps->lock);
683 	return sym;
684 }
685 
686 struct symbol *map_groups__find_symbol_by_name(struct map_groups *mg,
687 					       const char *name,
688 					       struct map **mapp)
689 {
690 	return maps__find_symbol_by_name(&mg->maps, name, mapp);
691 }
692 
693 int map_groups__find_ams(struct addr_map_symbol *ams)
694 {
695 	if (ams->addr < ams->map->start || ams->addr >= ams->map->end) {
696 		if (ams->map->groups == NULL)
697 			return -1;
698 		ams->map = map_groups__find(ams->map->groups, ams->addr);
699 		if (ams->map == NULL)
700 			return -1;
701 	}
702 
703 	ams->al_addr = ams->map->map_ip(ams->map, ams->addr);
704 	ams->sym = map__find_symbol(ams->map, ams->al_addr);
705 
706 	return ams->sym ? 0 : -1;
707 }
708 
709 static size_t maps__fprintf(struct maps *maps, FILE *fp)
710 {
711 	size_t printed = 0;
712 	struct rb_node *nd;
713 
714 	down_read(&maps->lock);
715 
716 	for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
717 		struct map *pos = rb_entry(nd, struct map, rb_node);
718 		printed += fprintf(fp, "Map:");
719 		printed += map__fprintf(pos, fp);
720 		if (verbose > 2) {
721 			printed += dso__fprintf(pos->dso, fp);
722 			printed += fprintf(fp, "--\n");
723 		}
724 	}
725 
726 	up_read(&maps->lock);
727 
728 	return printed;
729 }
730 
731 size_t map_groups__fprintf(struct map_groups *mg, FILE *fp)
732 {
733 	return maps__fprintf(&mg->maps, fp);
734 }
735 
736 static void __map_groups__insert(struct map_groups *mg, struct map *map)
737 {
738 	__maps__insert(&mg->maps, map);
739 	__maps__insert_name(&mg->maps, map);
740 	map->groups = mg;
741 }
742 
743 static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
744 {
745 	struct rb_root *root;
746 	struct rb_node *next, *first;
747 	int err = 0;
748 
749 	down_write(&maps->lock);
750 
751 	root = &maps->entries;
752 
753 	/*
754 	 * Find first map where end > map->start.
755 	 * Same as find_vma() in kernel.
756 	 */
757 	next = root->rb_node;
758 	first = NULL;
759 	while (next) {
760 		struct map *pos = rb_entry(next, struct map, rb_node);
761 
762 		if (pos->end > map->start) {
763 			first = next;
764 			if (pos->start <= map->start)
765 				break;
766 			next = next->rb_left;
767 		} else
768 			next = next->rb_right;
769 	}
770 
771 	next = first;
772 	while (next) {
773 		struct map *pos = rb_entry(next, struct map, rb_node);
774 		next = rb_next(&pos->rb_node);
775 
776 		/*
777 		 * Stop if current map starts after map->end.
778 		 * Maps are ordered by start: next will not overlap for sure.
779 		 */
780 		if (pos->start >= map->end)
781 			break;
782 
783 		if (verbose >= 2) {
784 
785 			if (use_browser) {
786 				pr_debug("overlapping maps in %s (disable tui for more info)\n",
787 					   map->dso->name);
788 			} else {
789 				fputs("overlapping maps:\n", fp);
790 				map__fprintf(map, fp);
791 				map__fprintf(pos, fp);
792 			}
793 		}
794 
795 		rb_erase_init(&pos->rb_node, root);
796 		/*
797 		 * Now check if we need to create new maps for areas not
798 		 * overlapped by the new map:
799 		 */
800 		if (map->start > pos->start) {
801 			struct map *before = map__clone(pos);
802 
803 			if (before == NULL) {
804 				err = -ENOMEM;
805 				goto put_map;
806 			}
807 
808 			before->end = map->start;
809 			__map_groups__insert(pos->groups, before);
810 			if (verbose >= 2 && !use_browser)
811 				map__fprintf(before, fp);
812 			map__put(before);
813 		}
814 
815 		if (map->end < pos->end) {
816 			struct map *after = map__clone(pos);
817 
818 			if (after == NULL) {
819 				err = -ENOMEM;
820 				goto put_map;
821 			}
822 
823 			after->start = map->end;
824 			__map_groups__insert(pos->groups, after);
825 			if (verbose >= 2 && !use_browser)
826 				map__fprintf(after, fp);
827 			map__put(after);
828 		}
829 put_map:
830 		map__put(pos);
831 
832 		if (err)
833 			goto out;
834 	}
835 
836 	err = 0;
837 out:
838 	up_write(&maps->lock);
839 	return err;
840 }
841 
842 int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
843 				   FILE *fp)
844 {
845 	return maps__fixup_overlappings(&mg->maps, map, fp);
846 }
847 
848 /*
849  * XXX This should not really _copy_ te maps, but refcount them.
850  */
851 int map_groups__clone(struct thread *thread, struct map_groups *parent)
852 {
853 	struct map_groups *mg = thread->mg;
854 	int err = -ENOMEM;
855 	struct map *map;
856 	struct maps *maps = &parent->maps;
857 
858 	down_read(&maps->lock);
859 
860 	for (map = maps__first(maps); map; map = map__next(map)) {
861 		struct map *new = map__clone(map);
862 		if (new == NULL)
863 			goto out_unlock;
864 
865 		err = unwind__prepare_access(thread, new, NULL);
866 		if (err)
867 			goto out_unlock;
868 
869 		map_groups__insert(mg, new);
870 		map__put(new);
871 	}
872 
873 	err = 0;
874 out_unlock:
875 	up_read(&maps->lock);
876 	return err;
877 }
878 
879 static void __maps__insert(struct maps *maps, struct map *map)
880 {
881 	struct rb_node **p = &maps->entries.rb_node;
882 	struct rb_node *parent = NULL;
883 	const u64 ip = map->start;
884 	struct map *m;
885 
886 	while (*p != NULL) {
887 		parent = *p;
888 		m = rb_entry(parent, struct map, rb_node);
889 		if (ip < m->start)
890 			p = &(*p)->rb_left;
891 		else
892 			p = &(*p)->rb_right;
893 	}
894 
895 	rb_link_node(&map->rb_node, parent, p);
896 	rb_insert_color(&map->rb_node, &maps->entries);
897 	map__get(map);
898 }
899 
900 static void __maps__insert_name(struct maps *maps, struct map *map)
901 {
902 	struct rb_node **p = &maps->names.rb_node;
903 	struct rb_node *parent = NULL;
904 	struct map *m;
905 	int rc;
906 
907 	while (*p != NULL) {
908 		parent = *p;
909 		m = rb_entry(parent, struct map, rb_node_name);
910 		rc = strcmp(m->dso->short_name, map->dso->short_name);
911 		if (rc < 0)
912 			p = &(*p)->rb_left;
913 		else if (rc  > 0)
914 			p = &(*p)->rb_right;
915 		else
916 			return;
917 	}
918 	rb_link_node(&map->rb_node_name, parent, p);
919 	rb_insert_color(&map->rb_node_name, &maps->names);
920 	map__get(map);
921 }
922 
923 void maps__insert(struct maps *maps, struct map *map)
924 {
925 	down_write(&maps->lock);
926 	__maps__insert(maps, map);
927 	__maps__insert_name(maps, map);
928 	up_write(&maps->lock);
929 }
930 
931 static void __maps__remove(struct maps *maps, struct map *map)
932 {
933 	rb_erase_init(&map->rb_node, &maps->entries);
934 	map__put(map);
935 
936 	rb_erase_init(&map->rb_node_name, &maps->names);
937 	map__put(map);
938 }
939 
940 void maps__remove(struct maps *maps, struct map *map)
941 {
942 	down_write(&maps->lock);
943 	__maps__remove(maps, map);
944 	up_write(&maps->lock);
945 }
946 
947 struct map *maps__find(struct maps *maps, u64 ip)
948 {
949 	struct rb_node *p;
950 	struct map *m;
951 
952 	down_read(&maps->lock);
953 
954 	p = maps->entries.rb_node;
955 	while (p != NULL) {
956 		m = rb_entry(p, struct map, rb_node);
957 		if (ip < m->start)
958 			p = p->rb_left;
959 		else if (ip >= m->end)
960 			p = p->rb_right;
961 		else
962 			goto out;
963 	}
964 
965 	m = NULL;
966 out:
967 	up_read(&maps->lock);
968 	return m;
969 }
970 
971 struct map *maps__first(struct maps *maps)
972 {
973 	struct rb_node *first = rb_first(&maps->entries);
974 
975 	if (first)
976 		return rb_entry(first, struct map, rb_node);
977 	return NULL;
978 }
979 
980 struct map *map__next(struct map *map)
981 {
982 	struct rb_node *next = rb_next(&map->rb_node);
983 
984 	if (next)
985 		return rb_entry(next, struct map, rb_node);
986 	return NULL;
987 }
988 
989 struct kmap *__map__kmap(struct map *map)
990 {
991 	if (!map->dso || !map->dso->kernel)
992 		return NULL;
993 	return (struct kmap *)(map + 1);
994 }
995 
996 struct kmap *map__kmap(struct map *map)
997 {
998 	struct kmap *kmap = __map__kmap(map);
999 
1000 	if (!kmap)
1001 		pr_err("Internal error: map__kmap with a non-kernel map\n");
1002 	return kmap;
1003 }
1004 
1005 struct map_groups *map__kmaps(struct map *map)
1006 {
1007 	struct kmap *kmap = map__kmap(map);
1008 
1009 	if (!kmap || !kmap->kmaps) {
1010 		pr_err("Internal error: map__kmaps with a non-kernel map\n");
1011 		return NULL;
1012 	}
1013 	return kmap->kmaps;
1014 }
1015