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1// SPDX-License-Identifier: GPL-2.0
2#include <inttypes.h>
3#include <limits.h>
4#include <stdio.h>
5#include <stdlib.h>
6#include <string.h>
7#include <linux/string.h>
8#include <linux/zalloc.h>
9#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
10#include "debug.h"
11#include "dso.h"
12#include "map.h"
13#include "namespaces.h"
14#include "srcline.h"
15#include "symbol.h"
16#include "thread.h"
17#include "vdso.h"
18
19static inline int is_android_lib(const char *filename)
20{
21 return strstarts(filename, "/data/app-lib/") ||
22 strstarts(filename, "/system/lib/");
23}
24
25static inline bool replace_android_lib(const char *filename, char *newfilename)
26{
27 const char *libname;
28 char *app_abi;
29 size_t app_abi_length, new_length;
30 size_t lib_length = 0;
31
32 libname = strrchr(filename, '/');
33 if (libname)
34 lib_length = strlen(libname);
35
36 app_abi = getenv("APP_ABI");
37 if (!app_abi)
38 return false;
39
40 app_abi_length = strlen(app_abi);
41
42 if (strstarts(filename, "/data/app-lib/")) {
43 char *apk_path;
44
45 if (!app_abi_length)
46 return false;
47
48 new_length = 7 + app_abi_length + lib_length;
49
50 apk_path = getenv("APK_PATH");
51 if (apk_path) {
52 new_length += strlen(apk_path) + 1;
53 if (new_length > PATH_MAX)
54 return false;
55 snprintf(newfilename, new_length,
56 "%s/libs/%s/%s", apk_path, app_abi, libname);
57 } else {
58 if (new_length > PATH_MAX)
59 return false;
60 snprintf(newfilename, new_length,
61 "libs/%s/%s", app_abi, libname);
62 }
63 return true;
64 }
65
66 if (strstarts(filename, "/system/lib/")) {
67 char *ndk, *app;
68 const char *arch;
69 int ndk_length, app_length;
70
71 ndk = getenv("NDK_ROOT");
72 app = getenv("APP_PLATFORM");
73
74 if (!(ndk && app))
75 return false;
76
77 ndk_length = strlen(ndk);
78 app_length = strlen(app);
79
80 if (!(ndk_length && app_length && app_abi_length))
81 return false;
82
83 arch = !strncmp(app_abi, "arm", 3) ? "arm" :
84 !strncmp(app_abi, "mips", 4) ? "mips" :
85 !strncmp(app_abi, "x86", 3) ? "x86" : NULL;
86
87 if (!arch)
88 return false;
89
90 new_length = 27 + ndk_length +
91 app_length + lib_length
92 + strlen(arch);
93
94 if (new_length > PATH_MAX)
95 return false;
96 snprintf(newfilename, new_length,
97 "%.*s/platforms/%.*s/arch-%s/usr/lib/%s",
98 ndk_length, ndk, app_length, app, arch, libname);
99
100 return true;
101 }
102 return false;
103}
104
105static void map__init(struct map *map, u64 start, u64 end, u64 pgoff,
106 struct dso *dso, u32 prot, u32 flags)
107{
108 map__set_start(map, start);
109 map__set_end(map, end);
110 map__set_pgoff(map, pgoff);
111 assert(map__reloc(map) == 0);
112 map__set_dso(map, dso__get(dso));
113 refcount_set(map__refcnt(map), 1);
114 RC_CHK_ACCESS(map)->prot = prot;
115 RC_CHK_ACCESS(map)->flags = flags;
116 map__set_mapping_type(map, MAPPING_TYPE__DSO);
117 assert(map__erange_warned(map) == false);
118 assert(map__priv(map) == false);
119 assert(map__hit(map) == false);
120}
121
122struct map *map__new(struct machine *machine, u64 start, u64 len,
123 u64 pgoff, const struct dso_id *id,
124 u32 prot, u32 flags,
125 char *filename, struct thread *thread)
126{
127 struct map *result;
128 RC_STRUCT(map) *map;
129 struct nsinfo *nsi = NULL;
130 struct nsinfo *nnsi;
131
132 map = zalloc(sizeof(*map));
133 if (ADD_RC_CHK(result, map)) {
134 char newfilename[PATH_MAX];
135 struct dso *dso;
136 int anon, no_dso, vdso, android;
137
138 android = is_android_lib(filename);
139 anon = is_anon_memory(filename) || flags & MAP_HUGETLB;
140 vdso = is_vdso_map(filename);
141 no_dso = is_no_dso_memory(filename);
142 nsi = nsinfo__get(thread__nsinfo(thread));
143
144 if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {
145 snprintf(newfilename, sizeof(newfilename),
146 "/tmp/perf-%d.map", nsinfo__pid(nsi));
147 filename = newfilename;
148 }
149
150 if (android) {
151 if (replace_android_lib(filename, newfilename))
152 filename = newfilename;
153 }
154
155 if (vdso) {
156 /* The vdso maps are always on the host and not the
157 * container. Ensure that we don't use setns to look
158 * them up.
159 */
160 nnsi = nsinfo__copy(nsi);
161 if (nnsi) {
162 nsinfo__put(nsi);
163 nsinfo__clear_need_setns(nnsi);
164 nsi = nnsi;
165 }
166 pgoff = 0;
167 dso = machine__findnew_vdso(machine, thread);
168 } else
169 dso = machine__findnew_dso_id(machine, filename, id);
170
171 if (dso == NULL)
172 goto out_delete;
173
174 assert(!dso__kernel(dso));
175 map__init(result, start, start + len, pgoff, dso, prot, flags);
176
177 if (anon || no_dso) {
178 map->mapping_type = MAPPING_TYPE__IDENTITY;
179
180 /*
181 * Set memory without DSO as loaded. All map__find_*
182 * functions still return NULL, and we avoid the
183 * unnecessary map__load warning.
184 */
185 if (!(prot & PROT_EXEC))
186 dso__set_loaded(dso);
187 }
188 mutex_lock(dso__lock(dso));
189 dso__set_nsinfo(dso, nsi);
190 mutex_unlock(dso__lock(dso));
191
192 if (!build_id__is_defined(&id->build_id)) {
193 /*
194 * If the mmap event had no build ID, search for an existing dso from the
195 * build ID header by name. Otherwise only the dso loaded at the time of
196 * reading the header will have the build ID set and all future mmaps will
197 * have it missing.
198 */
199 struct dso *header_bid_dso = dsos__find(&machine->dsos, filename, false);
200
201 if (header_bid_dso && dso__header_build_id(header_bid_dso)) {
202 dso__set_build_id(dso, dso__bid(header_bid_dso));
203 dso__set_header_build_id(dso, 1);
204 }
205 dso__put(header_bid_dso);
206 }
207 dso__put(dso);
208 }
209 return result;
210out_delete:
211 nsinfo__put(nsi);
212 RC_CHK_FREE(result);
213 return NULL;
214}
215
216/*
217 * Constructor variant for modules (where we know from /proc/modules where
218 * they are loaded) and for vmlinux, where only after we load all the
219 * symbols we'll know where it starts and ends.
220 */
221struct map *map__new2(u64 start, struct dso *dso)
222{
223 struct map *result;
224 RC_STRUCT(map) *map;
225
226 map = calloc(1, sizeof(*map) + (dso__kernel(dso) ? sizeof(struct kmap) : 0));
227 if (ADD_RC_CHK(result, map)) {
228 /* ->end will be filled after we load all the symbols. */
229 map__init(result, start, /*end=*/0, /*pgoff=*/0, dso, /*prot=*/0, /*flags=*/0);
230 }
231
232 return result;
233}
234
235bool __map__is_kernel(const struct map *map)
236{
237 if (!dso__kernel(map__dso(map)))
238 return false;
239 return machine__kernel_map(maps__machine(map__kmaps((struct map *)map))) == map;
240}
241
242bool __map__is_extra_kernel_map(const struct map *map)
243{
244 struct kmap *kmap = __map__kmap((struct map *)map);
245
246 return kmap && kmap->name[0];
247}
248
249bool __map__is_bpf_prog(const struct map *map)
250{
251 const char *name;
252 struct dso *dso = map__dso(map);
253
254 if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_PROG_INFO)
255 return true;
256
257 /*
258 * If PERF_RECORD_BPF_EVENT is not included, the dso will not have
259 * type of DSO_BINARY_TYPE__BPF_PROG_INFO. In such cases, we can
260 * guess the type based on name.
261 */
262 name = dso__short_name(dso);
263 return name && (strstr(name, "bpf_prog_") == name);
264}
265
266bool __map__is_bpf_image(const struct map *map)
267{
268 const char *name;
269 struct dso *dso = map__dso(map);
270
271 if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_IMAGE)
272 return true;
273
274 /*
275 * If PERF_RECORD_KSYMBOL is not included, the dso will not have
276 * type of DSO_BINARY_TYPE__BPF_IMAGE. In such cases, we can
277 * guess the type based on name.
278 */
279 name = dso__short_name(dso);
280 return name && is_bpf_image(name);
281}
282
283bool __map__is_ool(const struct map *map)
284{
285 const struct dso *dso = map__dso(map);
286
287 return dso && dso__binary_type(dso) == DSO_BINARY_TYPE__OOL;
288}
289
290bool map__has_symbols(const struct map *map)
291{
292 return dso__has_symbols(map__dso(map));
293}
294
295static void map__exit(struct map *map)
296{
297 BUG_ON(refcount_read(map__refcnt(map)) != 0);
298 dso__zput(RC_CHK_ACCESS(map)->dso);
299}
300
301void map__delete(struct map *map)
302{
303 map__exit(map);
304 RC_CHK_FREE(map);
305}
306
307void map__put(struct map *map)
308{
309 if (map && refcount_dec_and_test(map__refcnt(map)))
310 map__delete(map);
311 else
312 RC_CHK_PUT(map);
313}
314
315void map__fixup_start(struct map *map)
316{
317 struct dso *dso = map__dso(map);
318 struct rb_root_cached *symbols = dso__symbols(dso);
319 struct rb_node *nd = rb_first_cached(symbols);
320
321 if (nd != NULL) {
322 struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
323
324 map__set_start(map, sym->start);
325 }
326}
327
328void map__fixup_end(struct map *map)
329{
330 struct dso *dso = map__dso(map);
331 struct rb_root_cached *symbols = dso__symbols(dso);
332 struct rb_node *nd = rb_last(&symbols->rb_root);
333
334 if (nd != NULL) {
335 struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
336 map__set_end(map, sym->end);
337 }
338}
339
340#define DSO__DELETED "(deleted)"
341
342int map__load(struct map *map)
343{
344 struct dso *dso = map__dso(map);
345 const char *name = dso__long_name(dso);
346 int nr;
347
348 if (dso__loaded(dso))
349 return 0;
350
351 nr = dso__load(dso, map);
352 if (nr < 0) {
353 if (dso__has_build_id(dso)) {
354 char sbuild_id[SBUILD_ID_SIZE];
355
356 build_id__snprintf(dso__bid(dso), sbuild_id, sizeof(sbuild_id));
357 pr_debug("%s with build id %s not found", name, sbuild_id);
358 } else
359 pr_debug("Failed to open %s", name);
360
361 pr_debug(", continuing without symbols\n");
362 return -1;
363 } else if (nr == 0) {
364#ifdef HAVE_LIBELF_SUPPORT
365 const size_t len = strlen(name);
366 const size_t real_len = len - sizeof(DSO__DELETED);
367
368 if (len > sizeof(DSO__DELETED) &&
369 strcmp(name + real_len + 1, DSO__DELETED) == 0) {
370 pr_debug("%.*s was updated (is prelink enabled?). "
371 "Restart the long running apps that use it!\n",
372 (int)real_len, name);
373 } else {
374 pr_debug("no symbols found in %s, maybe install a debug package?\n", name);
375 }
376#endif
377 return -1;
378 }
379
380 return 0;
381}
382
383struct symbol *map__find_symbol(struct map *map, u64 addr)
384{
385 if (map__load(map) < 0)
386 return NULL;
387
388 return dso__find_symbol(map__dso(map), addr);
389}
390
391struct symbol *map__find_symbol_by_name_idx(struct map *map, const char *name, size_t *idx)
392{
393 struct dso *dso;
394
395 if (map__load(map) < 0)
396 return NULL;
397
398 dso = map__dso(map);
399 dso__sort_by_name(dso);
400
401 return dso__find_symbol_by_name(dso, name, idx);
402}
403
404struct symbol *map__find_symbol_by_name(struct map *map, const char *name)
405{
406 size_t idx;
407
408 return map__find_symbol_by_name_idx(map, name, &idx);
409}
410
411struct map *map__clone(struct map *from)
412{
413 struct map *result;
414 RC_STRUCT(map) *map;
415 size_t size = sizeof(RC_STRUCT(map));
416 struct dso *dso = map__dso(from);
417
418 if (dso && dso__kernel(dso))
419 size += sizeof(struct kmap);
420
421 map = memdup(RC_CHK_ACCESS(from), size);
422 if (ADD_RC_CHK(result, map)) {
423 refcount_set(&map->refcnt, 1);
424 map->dso = dso__get(dso);
425 }
426
427 return result;
428}
429
430size_t map__fprintf(struct map *map, FILE *fp)
431{
432 const struct dso *dso = map__dso(map);
433
434 return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
435 map__start(map), map__end(map), map__pgoff(map), dso__name(dso));
436}
437
438static bool prefer_dso_long_name(const struct dso *dso, bool print_off)
439{
440 return dso__long_name(dso) &&
441 (symbol_conf.show_kernel_path ||
442 (print_off && (dso__name(dso)[0] == '[' || dso__is_kcore(dso))));
443}
444
445static size_t __map__fprintf_dsoname(struct map *map, bool print_off, FILE *fp)
446{
447 char buf[symbol_conf.pad_output_len_dso + 1];
448 const char *dsoname = "[unknown]";
449 const struct dso *dso = map ? map__dso(map) : NULL;
450
451 if (dso) {
452 if (prefer_dso_long_name(dso, print_off))
453 dsoname = dso__long_name(dso);
454 else
455 dsoname = dso__name(dso);
456 }
457
458 if (symbol_conf.pad_output_len_dso) {
459 scnprintf_pad(buf, symbol_conf.pad_output_len_dso, "%s", dsoname);
460 dsoname = buf;
461 }
462
463 return fprintf(fp, "%s", dsoname);
464}
465
466size_t map__fprintf_dsoname(struct map *map, FILE *fp)
467{
468 return __map__fprintf_dsoname(map, false, fp);
469}
470
471size_t map__fprintf_dsoname_dsoff(struct map *map, bool print_off, u64 addr, FILE *fp)
472{
473 const struct dso *dso = map ? map__dso(map) : NULL;
474 int printed = 0;
475
476 if (print_off && (!dso || !dso__is_object_file(dso)))
477 print_off = false;
478 printed += fprintf(fp, " (");
479 printed += __map__fprintf_dsoname(map, print_off, fp);
480 if (print_off)
481 printed += fprintf(fp, "+0x%" PRIx64, addr);
482 printed += fprintf(fp, ")");
483
484 return printed;
485}
486
487char *map__srcline(struct map *map, u64 addr, struct symbol *sym)
488{
489 if (map == NULL)
490 return SRCLINE_UNKNOWN;
491
492 return get_srcline(map__dso(map), map__rip_2objdump(map, addr), sym, true, true, addr);
493}
494
495int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
496 FILE *fp)
497{
498 const struct dso *dso = map ? map__dso(map) : NULL;
499 int ret = 0;
500
501 if (dso) {
502 char *srcline = map__srcline(map, addr, NULL);
503 if (srcline != SRCLINE_UNKNOWN)
504 ret = fprintf(fp, "%s%s", prefix, srcline);
505 zfree_srcline(&srcline);
506 }
507 return ret;
508}
509
510void srccode_state_free(struct srccode_state *state)
511{
512 zfree(&state->srcfile);
513 state->line = 0;
514}
515
516static const struct kmap *__map__const_kmap(const struct map *map);
517
518/**
519 * map__rip_2objdump - convert symbol start address to objdump address.
520 * @map: memory map
521 * @rip: symbol start address
522 *
523 * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
524 * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
525 * relative to section start.
526 *
527 * Return: Address suitable for passing to "objdump --start-address="
528 */
529u64 map__rip_2objdump(const struct map *map, u64 rip)
530{
531 const struct kmap *kmap = __map__const_kmap(map);
532 const struct dso *dso = map__dso(map);
533
534 /*
535 * vmlinux does not have program headers for PTI entry trampolines and
536 * kcore may not either. However the trampoline object code is on the
537 * main kernel map, so just use that instead.
538 */
539 if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps) {
540 struct machine *machine = maps__machine(kmap->kmaps);
541
542 if (machine) {
543 struct map *kernel_map = machine__kernel_map(machine);
544
545 if (kernel_map)
546 map = kernel_map;
547 }
548 }
549
550 if (!dso__adjust_symbols(dso))
551 return rip;
552
553 if (dso__rel(dso))
554 return rip - map__pgoff(map);
555
556 if (dso__kernel(dso) == DSO_SPACE__USER)
557 return rip + dso__text_offset(dso);
558
559 return map__unmap_ip(map, rip) - map__reloc(map);
560}
561
562/**
563 * map__objdump_2mem - convert objdump address to a memory address.
564 * @map: memory map
565 * @ip: objdump address
566 *
567 * Closely related to map__rip_2objdump(), this function takes an address from
568 * objdump and converts it to a memory address. Note this assumes that @map
569 * contains the address. To be sure the result is valid, check it forwards
570 * e.g. map__rip_2objdump(map__map_ip(map, map__objdump_2mem(map, ip))) == ip
571 *
572 * Return: Memory address.
573 */
574u64 map__objdump_2mem(const struct map *map, u64 ip)
575{
576 const struct dso *dso = map__dso(map);
577
578 if (!dso__adjust_symbols(dso))
579 return map__unmap_ip(map, ip);
580
581 if (dso__rel(dso))
582 return map__unmap_ip(map, ip + map__pgoff(map));
583
584 if (dso__kernel(dso) == DSO_SPACE__USER)
585 return map__unmap_ip(map, ip - dso__text_offset(dso));
586
587 return ip + map__reloc(map);
588}
589
590/* convert objdump address to relative address. (To be removed) */
591u64 map__objdump_2rip(const struct map *map, u64 ip)
592{
593 const struct dso *dso = map__dso(map);
594
595 if (!dso__adjust_symbols(dso))
596 return ip;
597
598 if (dso__rel(dso))
599 return ip + map__pgoff(map);
600
601 if (dso__kernel(dso) == DSO_SPACE__USER)
602 return ip - dso__text_offset(dso);
603
604 return map__map_ip(map, ip + map__reloc(map));
605}
606
607bool map__contains_symbol(const struct map *map, const struct symbol *sym)
608{
609 u64 ip = map__unmap_ip(map, sym->start);
610
611 return ip >= map__start(map) && ip < map__end(map);
612}
613
614struct kmap *__map__kmap(struct map *map)
615{
616 const struct dso *dso = map__dso(map);
617
618 if (!dso || !dso__kernel(dso))
619 return NULL;
620 return (struct kmap *)(&RC_CHK_ACCESS(map)[1]);
621}
622
623static const struct kmap *__map__const_kmap(const struct map *map)
624{
625 const struct dso *dso = map__dso(map);
626
627 if (!dso || !dso__kernel(dso))
628 return NULL;
629 return (struct kmap *)(&RC_CHK_ACCESS(map)[1]);
630}
631
632struct kmap *map__kmap(struct map *map)
633{
634 struct kmap *kmap = __map__kmap(map);
635
636 if (!kmap)
637 pr_err("Internal error: map__kmap with a non-kernel map\n");
638 return kmap;
639}
640
641struct maps *map__kmaps(struct map *map)
642{
643 struct kmap *kmap = map__kmap(map);
644
645 if (!kmap || !kmap->kmaps) {
646 pr_err("Internal error: map__kmaps with a non-kernel map\n");
647 return NULL;
648 }
649 return kmap->kmaps;
650}