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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * build-id.c
4 *
5 * build-id support
6 *
7 * Copyright (C) 2009, 2010 Red Hat Inc.
8 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
9 */
10#include "util.h" // lsdir(), mkdir_p(), rm_rf()
11#include <dirent.h>
12#include <errno.h>
13#include <stdio.h>
14#include <sys/stat.h>
15#include <sys/types.h>
16#include "util/copyfile.h"
17#include "dso.h"
18#include "build-id.h"
19#include "event.h"
20#include "namespaces.h"
21#include "map.h"
22#include "symbol.h"
23#include "thread.h"
24#include <linux/kernel.h>
25#include "debug.h"
26#include "session.h"
27#include "tool.h"
28#include "header.h"
29#include "vdso.h"
30#include "path.h"
31#include "probe-file.h"
32#include "strlist.h"
33
34#ifdef HAVE_DEBUGINFOD_SUPPORT
35#include <elfutils/debuginfod.h>
36#endif
37
38#include <linux/ctype.h>
39#include <linux/zalloc.h>
40#include <linux/string.h>
41#include <asm/bug.h>
42
43static bool no_buildid_cache;
44
45int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
46 union perf_event *event,
47 struct perf_sample *sample,
48 struct evsel *evsel __maybe_unused,
49 struct machine *machine)
50{
51 struct addr_location al;
52 struct thread *thread = machine__findnew_thread(machine, sample->pid,
53 sample->tid);
54
55 if (thread == NULL) {
56 pr_err("problem processing %d event, skipping it.\n",
57 event->header.type);
58 return -1;
59 }
60
61 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
62 al.map->dso->hit = 1;
63
64 thread__put(thread);
65 return 0;
66}
67
68static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
69 union perf_event *event,
70 struct perf_sample *sample
71 __maybe_unused,
72 struct machine *machine)
73{
74 struct thread *thread = machine__findnew_thread(machine,
75 event->fork.pid,
76 event->fork.tid);
77
78 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
79 event->fork.ppid, event->fork.ptid);
80
81 if (thread) {
82 machine__remove_thread(machine, thread);
83 thread__put(thread);
84 }
85
86 return 0;
87}
88
89struct perf_tool build_id__mark_dso_hit_ops = {
90 .sample = build_id__mark_dso_hit,
91 .mmap = perf_event__process_mmap,
92 .mmap2 = perf_event__process_mmap2,
93 .fork = perf_event__process_fork,
94 .exit = perf_event__exit_del_thread,
95 .attr = perf_event__process_attr,
96 .build_id = perf_event__process_build_id,
97 .ordered_events = true,
98};
99
100int build_id__sprintf(const struct build_id *build_id, char *bf)
101{
102 char *bid = bf;
103 const u8 *raw = build_id->data;
104 size_t i;
105
106 bf[0] = 0x0;
107
108 for (i = 0; i < build_id->size; ++i) {
109 sprintf(bid, "%02x", *raw);
110 ++raw;
111 bid += 2;
112 }
113
114 return (bid - bf) + 1;
115}
116
117int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
118{
119 char notes[PATH_MAX];
120 struct build_id bid;
121 int ret;
122
123 if (!root_dir)
124 root_dir = "";
125
126 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
127
128 ret = sysfs__read_build_id(notes, &bid);
129 if (ret < 0)
130 return ret;
131
132 return build_id__sprintf(&bid, sbuild_id);
133}
134
135int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
136{
137 struct build_id bid;
138 int ret;
139
140 ret = filename__read_build_id(pathname, &bid);
141 if (ret < 0)
142 return ret;
143
144 return build_id__sprintf(&bid, sbuild_id);
145}
146
147/* asnprintf consolidates asprintf and snprintf */
148static int asnprintf(char **strp, size_t size, const char *fmt, ...)
149{
150 va_list ap;
151 int ret;
152
153 if (!strp)
154 return -EINVAL;
155
156 va_start(ap, fmt);
157 if (*strp)
158 ret = vsnprintf(*strp, size, fmt, ap);
159 else
160 ret = vasprintf(strp, fmt, ap);
161 va_end(ap);
162
163 return ret;
164}
165
166char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
167 size_t size)
168{
169 bool retry_old = true;
170
171 snprintf(bf, size, "%s/%s/%s/kallsyms",
172 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
173retry:
174 if (!access(bf, F_OK))
175 return bf;
176 if (retry_old) {
177 /* Try old style kallsyms cache */
178 snprintf(bf, size, "%s/%s/%s",
179 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
180 retry_old = false;
181 goto retry;
182 }
183
184 return NULL;
185}
186
187char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
188{
189 char *tmp = bf;
190 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
191 sbuild_id, sbuild_id + 2);
192 if (ret < 0 || (tmp && size < (unsigned int)ret))
193 return NULL;
194 return bf;
195}
196
197/* The caller is responsible to free the returned buffer. */
198char *build_id_cache__origname(const char *sbuild_id)
199{
200 char *linkname;
201 char buf[PATH_MAX];
202 char *ret = NULL, *p;
203 size_t offs = 5; /* == strlen("../..") */
204 ssize_t len;
205
206 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
207 if (!linkname)
208 return NULL;
209
210 len = readlink(linkname, buf, sizeof(buf) - 1);
211 if (len <= 0)
212 goto out;
213 buf[len] = '\0';
214
215 /* The link should be "../..<origpath>/<sbuild_id>" */
216 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
217 if (p && (p > buf + offs)) {
218 *p = '\0';
219 if (buf[offs + 1] == '[')
220 offs++; /*
221 * This is a DSO name, like [kernel.kallsyms].
222 * Skip the first '/', since this is not the
223 * cache of a regular file.
224 */
225 ret = strdup(buf + offs); /* Skip "../..[/]" */
226 }
227out:
228 free(linkname);
229 return ret;
230}
231
232/* Check if the given build_id cache is valid on current running system */
233static bool build_id_cache__valid_id(char *sbuild_id)
234{
235 char real_sbuild_id[SBUILD_ID_SIZE] = "";
236 char *pathname;
237 int ret = 0;
238 bool result = false;
239
240 pathname = build_id_cache__origname(sbuild_id);
241 if (!pathname)
242 return false;
243
244 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
245 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
246 else if (pathname[0] == '/')
247 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
248 else
249 ret = -EINVAL; /* Should we support other special DSO cache? */
250 if (ret >= 0)
251 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
252 free(pathname);
253
254 return result;
255}
256
257static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
258 bool is_debug)
259{
260 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
261 "debug" : "elf"));
262}
263
264char *__dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
265 bool is_debug, bool is_kallsyms)
266{
267 bool is_vdso = dso__is_vdso((struct dso *)dso);
268 char sbuild_id[SBUILD_ID_SIZE];
269 char *linkname;
270 bool alloc = (bf == NULL);
271 int ret;
272
273 if (!dso->has_build_id)
274 return NULL;
275
276 build_id__sprintf(&dso->bid, sbuild_id);
277 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
278 if (!linkname)
279 return NULL;
280
281 /* Check if old style build_id cache */
282 if (is_regular_file(linkname))
283 ret = asnprintf(&bf, size, "%s", linkname);
284 else
285 ret = asnprintf(&bf, size, "%s/%s", linkname,
286 build_id_cache__basename(is_kallsyms, is_vdso,
287 is_debug));
288 if (ret < 0 || (!alloc && size < (unsigned int)ret))
289 bf = NULL;
290 free(linkname);
291
292 return bf;
293}
294
295char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
296 bool is_debug)
297{
298 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
299
300 return __dso__build_id_filename(dso, bf, size, is_debug, is_kallsyms);
301}
302
303static int write_buildid(const char *name, size_t name_len, struct build_id *bid,
304 pid_t pid, u16 misc, struct feat_fd *fd)
305{
306 int err;
307 struct perf_record_header_build_id b;
308 size_t len;
309
310 len = name_len + 1;
311 len = PERF_ALIGN(len, NAME_ALIGN);
312
313 memset(&b, 0, sizeof(b));
314 memcpy(&b.data, bid->data, bid->size);
315 b.size = (u8) bid->size;
316 misc |= PERF_RECORD_MISC_BUILD_ID_SIZE;
317 b.pid = pid;
318 b.header.misc = misc;
319 b.header.size = sizeof(b) + len;
320
321 err = do_write(fd, &b, sizeof(b));
322 if (err < 0)
323 return err;
324
325 return write_padded(fd, name, name_len + 1, len);
326}
327
328static int machine__write_buildid_table(struct machine *machine,
329 struct feat_fd *fd)
330{
331 int err = 0;
332 struct dso *pos;
333 u16 kmisc = PERF_RECORD_MISC_KERNEL,
334 umisc = PERF_RECORD_MISC_USER;
335
336 if (!machine__is_host(machine)) {
337 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
338 umisc = PERF_RECORD_MISC_GUEST_USER;
339 }
340
341 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
342 const char *name;
343 size_t name_len;
344 bool in_kernel = false;
345
346 if (!pos->hit && !dso__is_vdso(pos))
347 continue;
348
349 if (dso__is_vdso(pos)) {
350 name = pos->short_name;
351 name_len = pos->short_name_len;
352 } else if (dso__is_kcore(pos)) {
353 name = machine->mmap_name;
354 name_len = strlen(name);
355 } else {
356 name = pos->long_name;
357 name_len = pos->long_name_len;
358 }
359
360 in_kernel = pos->kernel ||
361 is_kernel_module(name,
362 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
363 err = write_buildid(name, name_len, &pos->bid, machine->pid,
364 in_kernel ? kmisc : umisc, fd);
365 if (err)
366 break;
367 }
368
369 return err;
370}
371
372int perf_session__write_buildid_table(struct perf_session *session,
373 struct feat_fd *fd)
374{
375 struct rb_node *nd;
376 int err = machine__write_buildid_table(&session->machines.host, fd);
377
378 if (err)
379 return err;
380
381 for (nd = rb_first_cached(&session->machines.guests); nd;
382 nd = rb_next(nd)) {
383 struct machine *pos = rb_entry(nd, struct machine, rb_node);
384 err = machine__write_buildid_table(pos, fd);
385 if (err)
386 break;
387 }
388 return err;
389}
390
391static int __dsos__hit_all(struct list_head *head)
392{
393 struct dso *pos;
394
395 list_for_each_entry(pos, head, node)
396 pos->hit = true;
397
398 return 0;
399}
400
401static int machine__hit_all_dsos(struct machine *machine)
402{
403 return __dsos__hit_all(&machine->dsos.head);
404}
405
406int dsos__hit_all(struct perf_session *session)
407{
408 struct rb_node *nd;
409 int err;
410
411 err = machine__hit_all_dsos(&session->machines.host);
412 if (err)
413 return err;
414
415 for (nd = rb_first_cached(&session->machines.guests); nd;
416 nd = rb_next(nd)) {
417 struct machine *pos = rb_entry(nd, struct machine, rb_node);
418
419 err = machine__hit_all_dsos(pos);
420 if (err)
421 return err;
422 }
423
424 return 0;
425}
426
427void disable_buildid_cache(void)
428{
429 no_buildid_cache = true;
430}
431
432static bool lsdir_bid_head_filter(const char *name __maybe_unused,
433 struct dirent *d)
434{
435 return (strlen(d->d_name) == 2) &&
436 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
437}
438
439static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
440 struct dirent *d)
441{
442 int i = 0;
443 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
444 i++;
445 return (i >= SBUILD_ID_MIN_SIZE - 3) && (i <= SBUILD_ID_SIZE - 3) &&
446 (d->d_name[i] == '\0');
447}
448
449struct strlist *build_id_cache__list_all(bool validonly)
450{
451 struct strlist *toplist, *linklist = NULL, *bidlist;
452 struct str_node *nd, *nd2;
453 char *topdir, *linkdir = NULL;
454 char sbuild_id[SBUILD_ID_SIZE];
455
456 /* for filename__ functions */
457 if (validonly)
458 symbol__init(NULL);
459
460 /* Open the top-level directory */
461 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
462 return NULL;
463
464 bidlist = strlist__new(NULL, NULL);
465 if (!bidlist)
466 goto out;
467
468 toplist = lsdir(topdir, lsdir_bid_head_filter);
469 if (!toplist) {
470 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
471 /* If there is no buildid cache, return an empty list */
472 if (errno == ENOENT)
473 goto out;
474 goto err_out;
475 }
476
477 strlist__for_each_entry(nd, toplist) {
478 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
479 goto err_out;
480 /* Open the lower-level directory */
481 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
482 if (!linklist) {
483 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
484 goto err_out;
485 }
486 strlist__for_each_entry(nd2, linklist) {
487 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
488 nd->s, nd2->s) > SBUILD_ID_SIZE - 1)
489 goto err_out;
490 if (validonly && !build_id_cache__valid_id(sbuild_id))
491 continue;
492 if (strlist__add(bidlist, sbuild_id) < 0)
493 goto err_out;
494 }
495 strlist__delete(linklist);
496 zfree(&linkdir);
497 }
498
499out_free:
500 strlist__delete(toplist);
501out:
502 free(topdir);
503
504 return bidlist;
505
506err_out:
507 strlist__delete(linklist);
508 zfree(&linkdir);
509 strlist__delete(bidlist);
510 bidlist = NULL;
511 goto out_free;
512}
513
514static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
515{
516 size_t i;
517
518 for (i = 0; i < len; i++) {
519 if (!isxdigit(maybe_sbuild_id[i]))
520 return false;
521 }
522 return true;
523}
524
525/* Return the valid complete build-id */
526char *build_id_cache__complement(const char *incomplete_sbuild_id)
527{
528 struct strlist *bidlist;
529 struct str_node *nd, *cand = NULL;
530 char *sbuild_id = NULL;
531 size_t len = strlen(incomplete_sbuild_id);
532
533 if (len >= SBUILD_ID_SIZE ||
534 !str_is_build_id(incomplete_sbuild_id, len))
535 return NULL;
536
537 bidlist = build_id_cache__list_all(true);
538 if (!bidlist)
539 return NULL;
540
541 strlist__for_each_entry(nd, bidlist) {
542 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
543 continue;
544 if (cand) { /* Error: There are more than 2 candidates. */
545 cand = NULL;
546 break;
547 }
548 cand = nd;
549 }
550 if (cand)
551 sbuild_id = strdup(cand->s);
552 strlist__delete(bidlist);
553
554 return sbuild_id;
555}
556
557char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
558 struct nsinfo *nsi, bool is_kallsyms,
559 bool is_vdso)
560{
561 char *realname = (char *)name, *filename;
562 bool slash = is_kallsyms || is_vdso;
563
564 if (!slash)
565 realname = nsinfo__realpath(name, nsi);
566
567 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
568 is_vdso ? DSO__NAME_VDSO : (realname ? realname : name),
569 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
570 filename = NULL;
571
572 if (!slash)
573 free(realname);
574
575 return filename;
576}
577
578int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
579 struct strlist **result)
580{
581 char *dir_name;
582 int ret = 0;
583
584 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
585 if (!dir_name)
586 return -ENOMEM;
587
588 *result = lsdir(dir_name, lsdir_no_dot_filter);
589 if (!*result)
590 ret = -errno;
591 free(dir_name);
592
593 return ret;
594}
595
596#if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
597static int build_id_cache__add_sdt_cache(const char *sbuild_id,
598 const char *realname,
599 struct nsinfo *nsi)
600{
601 struct probe_cache *cache;
602 int ret;
603 struct nscookie nsc;
604
605 cache = probe_cache__new(sbuild_id, nsi);
606 if (!cache)
607 return -1;
608
609 nsinfo__mountns_enter(nsi, &nsc);
610 ret = probe_cache__scan_sdt(cache, realname);
611 nsinfo__mountns_exit(&nsc);
612 if (ret >= 0) {
613 pr_debug4("Found %d SDTs in %s\n", ret, realname);
614 if (probe_cache__commit(cache) < 0)
615 ret = -1;
616 }
617 probe_cache__delete(cache);
618 return ret;
619}
620#else
621#define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
622#endif
623
624static char *build_id_cache__find_debug(const char *sbuild_id,
625 struct nsinfo *nsi,
626 const char *root_dir)
627{
628 const char *dirname = "/usr/lib/debug/.build-id/";
629 char *realname = NULL;
630 char dirbuf[PATH_MAX];
631 char *debugfile;
632 struct nscookie nsc;
633 size_t len = 0;
634
635 debugfile = calloc(1, PATH_MAX);
636 if (!debugfile)
637 goto out;
638
639 if (root_dir) {
640 path__join(dirbuf, PATH_MAX, root_dir, dirname);
641 dirname = dirbuf;
642 }
643
644 len = __symbol__join_symfs(debugfile, PATH_MAX, dirname);
645 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
646 sbuild_id + 2);
647
648 nsinfo__mountns_enter(nsi, &nsc);
649 realname = realpath(debugfile, NULL);
650 if (realname && access(realname, R_OK))
651 zfree(&realname);
652 nsinfo__mountns_exit(&nsc);
653
654#ifdef HAVE_DEBUGINFOD_SUPPORT
655 if (realname == NULL) {
656 debuginfod_client* c;
657
658 pr_debug("Downloading debug info with build id %s\n", sbuild_id);
659
660 c = debuginfod_begin();
661 if (c != NULL) {
662 int fd = debuginfod_find_debuginfo(c,
663 (const unsigned char*)sbuild_id, 0,
664 &realname);
665 if (fd >= 0)
666 close(fd); /* retaining reference by realname */
667 debuginfod_end(c);
668 }
669 }
670#endif
671
672out:
673 free(debugfile);
674 return realname;
675}
676
677int
678build_id_cache__add(const char *sbuild_id, const char *name, const char *realname,
679 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
680 const char *proper_name, const char *root_dir)
681{
682 const size_t size = PATH_MAX;
683 char *filename = NULL, *dir_name = NULL, *linkname = zalloc(size), *tmp;
684 char *debugfile = NULL;
685 int err = -1;
686
687 if (!proper_name)
688 proper_name = name;
689
690 dir_name = build_id_cache__cachedir(sbuild_id, proper_name, nsi, is_kallsyms,
691 is_vdso);
692 if (!dir_name)
693 goto out_free;
694
695 /* Remove old style build-id cache */
696 if (is_regular_file(dir_name))
697 if (unlink(dir_name))
698 goto out_free;
699
700 if (mkdir_p(dir_name, 0755))
701 goto out_free;
702
703 /* Save the allocated buildid dirname */
704 if (asprintf(&filename, "%s/%s", dir_name,
705 build_id_cache__basename(is_kallsyms, is_vdso,
706 false)) < 0) {
707 filename = NULL;
708 goto out_free;
709 }
710
711 if (access(filename, F_OK)) {
712 if (is_kallsyms) {
713 if (copyfile("/proc/kallsyms", filename))
714 goto out_free;
715 } else if (nsi && nsinfo__need_setns(nsi)) {
716 if (copyfile_ns(name, filename, nsi))
717 goto out_free;
718 } else if (link(realname, filename) && errno != EEXIST) {
719 struct stat f_stat;
720
721 if (!(stat(name, &f_stat) < 0) &&
722 copyfile_mode(name, filename, f_stat.st_mode))
723 goto out_free;
724 }
725 }
726
727 /* Some binaries are stripped, but have .debug files with their symbol
728 * table. Check to see if we can locate one of those, since the elf
729 * file itself may not be very useful to users of our tools without a
730 * symtab.
731 */
732 if (!is_kallsyms && !is_vdso &&
733 strncmp(".ko", name + strlen(name) - 3, 3)) {
734 debugfile = build_id_cache__find_debug(sbuild_id, nsi, root_dir);
735 if (debugfile) {
736 zfree(&filename);
737 if (asprintf(&filename, "%s/%s", dir_name,
738 build_id_cache__basename(false, false, true)) < 0) {
739 filename = NULL;
740 goto out_free;
741 }
742 if (access(filename, F_OK)) {
743 if (nsi && nsinfo__need_setns(nsi)) {
744 if (copyfile_ns(debugfile, filename,
745 nsi))
746 goto out_free;
747 } else if (link(debugfile, filename) &&
748 errno != EEXIST &&
749 copyfile(debugfile, filename))
750 goto out_free;
751 }
752 }
753 }
754
755 if (!build_id_cache__linkname(sbuild_id, linkname, size))
756 goto out_free;
757 tmp = strrchr(linkname, '/');
758 *tmp = '\0';
759
760 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
761 goto out_free;
762
763 *tmp = '/';
764 tmp = dir_name + strlen(buildid_dir) - 5;
765 memcpy(tmp, "../..", 5);
766
767 if (symlink(tmp, linkname) == 0) {
768 err = 0;
769 } else if (errno == EEXIST) {
770 char path[PATH_MAX];
771 ssize_t len;
772
773 len = readlink(linkname, path, sizeof(path) - 1);
774 if (len <= 0) {
775 pr_err("Can't read link: %s\n", linkname);
776 goto out_free;
777 }
778 path[len] = '\0';
779
780 if (strcmp(tmp, path)) {
781 pr_debug("build <%s> already linked to %s\n",
782 sbuild_id, linkname);
783 }
784 err = 0;
785 }
786
787 /* Update SDT cache : error is just warned */
788 if (realname &&
789 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
790 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
791
792out_free:
793 free(filename);
794 free(debugfile);
795 free(dir_name);
796 free(linkname);
797 return err;
798}
799
800int __build_id_cache__add_s(const char *sbuild_id, const char *name,
801 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
802 const char *proper_name, const char *root_dir)
803{
804 char *realname = NULL;
805 int err = -1;
806
807 if (!is_kallsyms) {
808 if (!is_vdso)
809 realname = nsinfo__realpath(name, nsi);
810 else
811 realname = realpath(name, NULL);
812 if (!realname)
813 goto out_free;
814 }
815
816 err = build_id_cache__add(sbuild_id, name, realname, nsi,
817 is_kallsyms, is_vdso, proper_name, root_dir);
818out_free:
819 if (!is_kallsyms)
820 free(realname);
821 return err;
822}
823
824static int build_id_cache__add_b(const struct build_id *bid,
825 const char *name, struct nsinfo *nsi,
826 bool is_kallsyms, bool is_vdso,
827 const char *proper_name,
828 const char *root_dir)
829{
830 char sbuild_id[SBUILD_ID_SIZE];
831
832 build_id__sprintf(bid, sbuild_id);
833
834 return __build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
835 is_vdso, proper_name, root_dir);
836}
837
838bool build_id_cache__cached(const char *sbuild_id)
839{
840 bool ret = false;
841 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
842
843 if (filename && !access(filename, F_OK))
844 ret = true;
845 free(filename);
846
847 return ret;
848}
849
850int build_id_cache__remove_s(const char *sbuild_id)
851{
852 const size_t size = PATH_MAX;
853 char *filename = zalloc(size),
854 *linkname = zalloc(size), *tmp;
855 int err = -1;
856
857 if (filename == NULL || linkname == NULL)
858 goto out_free;
859
860 if (!build_id_cache__linkname(sbuild_id, linkname, size))
861 goto out_free;
862
863 if (access(linkname, F_OK))
864 goto out_free;
865
866 if (readlink(linkname, filename, size - 1) < 0)
867 goto out_free;
868
869 if (unlink(linkname))
870 goto out_free;
871
872 /*
873 * Since the link is relative, we must make it absolute:
874 */
875 tmp = strrchr(linkname, '/') + 1;
876 snprintf(tmp, size - (tmp - linkname), "%s", filename);
877
878 if (rm_rf(linkname))
879 goto out_free;
880
881 err = 0;
882out_free:
883 free(filename);
884 free(linkname);
885 return err;
886}
887
888static int filename__read_build_id_ns(const char *filename,
889 struct build_id *bid,
890 struct nsinfo *nsi)
891{
892 struct nscookie nsc;
893 int ret;
894
895 nsinfo__mountns_enter(nsi, &nsc);
896 ret = filename__read_build_id(filename, bid);
897 nsinfo__mountns_exit(&nsc);
898
899 return ret;
900}
901
902static bool dso__build_id_mismatch(struct dso *dso, const char *name)
903{
904 struct build_id bid;
905 bool ret = false;
906
907 mutex_lock(&dso->lock);
908 if (filename__read_build_id_ns(name, &bid, dso->nsinfo) >= 0)
909 ret = !dso__build_id_equal(dso, &bid);
910
911 mutex_unlock(&dso->lock);
912
913 return ret;
914}
915
916static int dso__cache_build_id(struct dso *dso, struct machine *machine,
917 void *priv __maybe_unused)
918{
919 bool is_kallsyms = dso__is_kallsyms(dso);
920 bool is_vdso = dso__is_vdso(dso);
921 const char *name = dso->long_name;
922 const char *proper_name = NULL;
923 const char *root_dir = NULL;
924 char *allocated_name = NULL;
925 int ret = 0;
926
927 if (!dso->has_build_id)
928 return 0;
929
930 if (dso__is_kcore(dso)) {
931 is_kallsyms = true;
932 name = machine->mmap_name;
933 }
934
935 if (!machine__is_host(machine)) {
936 if (*machine->root_dir) {
937 root_dir = machine->root_dir;
938 ret = asprintf(&allocated_name, "%s/%s", root_dir, name);
939 if (ret < 0)
940 return ret;
941 proper_name = name;
942 name = allocated_name;
943 } else if (is_kallsyms) {
944 /* Cannot get guest kallsyms */
945 return 0;
946 }
947 }
948
949 if (!is_kallsyms && dso__build_id_mismatch(dso, name))
950 goto out_free;
951
952 mutex_lock(&dso->lock);
953 ret = build_id_cache__add_b(&dso->bid, name, dso->nsinfo,
954 is_kallsyms, is_vdso, proper_name, root_dir);
955 mutex_unlock(&dso->lock);
956out_free:
957 free(allocated_name);
958 return ret;
959}
960
961static int
962machines__for_each_dso(struct machines *machines, machine__dso_t fn, void *priv)
963{
964 int ret = machine__for_each_dso(&machines->host, fn, priv);
965 struct rb_node *nd;
966
967 for (nd = rb_first_cached(&machines->guests); nd;
968 nd = rb_next(nd)) {
969 struct machine *pos = rb_entry(nd, struct machine, rb_node);
970
971 ret |= machine__for_each_dso(pos, fn, priv);
972 }
973 return ret ? -1 : 0;
974}
975
976int __perf_session__cache_build_ids(struct perf_session *session,
977 machine__dso_t fn, void *priv)
978{
979 if (no_buildid_cache)
980 return 0;
981
982 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
983 return -1;
984
985 return machines__for_each_dso(&session->machines, fn, priv) ? -1 : 0;
986}
987
988int perf_session__cache_build_ids(struct perf_session *session)
989{
990 return __perf_session__cache_build_ids(session, dso__cache_build_id, NULL);
991}
992
993static bool machine__read_build_ids(struct machine *machine, bool with_hits)
994{
995 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
996}
997
998bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
999{
1000 struct rb_node *nd;
1001 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
1002
1003 for (nd = rb_first_cached(&session->machines.guests); nd;
1004 nd = rb_next(nd)) {
1005 struct machine *pos = rb_entry(nd, struct machine, rb_node);
1006 ret |= machine__read_build_ids(pos, with_hits);
1007 }
1008
1009 return ret;
1010}
1011
1012void build_id__init(struct build_id *bid, const u8 *data, size_t size)
1013{
1014 WARN_ON(size > BUILD_ID_SIZE);
1015 memcpy(bid->data, data, size);
1016 bid->size = size;
1017}
1018
1019bool build_id__is_defined(const struct build_id *bid)
1020{
1021 return bid && bid->size ? !!memchr_inv(bid->data, 0, bid->size) : false;
1022}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * build-id.c
4 *
5 * build-id support
6 *
7 * Copyright (C) 2009, 2010 Red Hat Inc.
8 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
9 */
10#include "util.h" // lsdir(), mkdir_p(), rm_rf()
11#include <dirent.h>
12#include <errno.h>
13#include <stdio.h>
14#include <sys/stat.h>
15#include <sys/types.h>
16#include "util/copyfile.h"
17#include "dso.h"
18#include "build-id.h"
19#include "event.h"
20#include "namespaces.h"
21#include "map.h"
22#include "symbol.h"
23#include "thread.h"
24#include <linux/kernel.h>
25#include "debug.h"
26#include "session.h"
27#include "tool.h"
28#include "header.h"
29#include "vdso.h"
30#include "path.h"
31#include "probe-file.h"
32#include "strlist.h"
33
34#ifdef HAVE_DEBUGINFOD_SUPPORT
35#include <elfutils/debuginfod.h>
36#endif
37
38#include <linux/ctype.h>
39#include <linux/zalloc.h>
40
41static bool no_buildid_cache;
42
43int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
44 union perf_event *event,
45 struct perf_sample *sample,
46 struct evsel *evsel __maybe_unused,
47 struct machine *machine)
48{
49 struct addr_location al;
50 struct thread *thread = machine__findnew_thread(machine, sample->pid,
51 sample->tid);
52
53 if (thread == NULL) {
54 pr_err("problem processing %d event, skipping it.\n",
55 event->header.type);
56 return -1;
57 }
58
59 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
60 al.map->dso->hit = 1;
61
62 thread__put(thread);
63 return 0;
64}
65
66static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
67 union perf_event *event,
68 struct perf_sample *sample
69 __maybe_unused,
70 struct machine *machine)
71{
72 struct thread *thread = machine__findnew_thread(machine,
73 event->fork.pid,
74 event->fork.tid);
75
76 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
77 event->fork.ppid, event->fork.ptid);
78
79 if (thread) {
80 machine__remove_thread(machine, thread);
81 thread__put(thread);
82 }
83
84 return 0;
85}
86
87struct perf_tool build_id__mark_dso_hit_ops = {
88 .sample = build_id__mark_dso_hit,
89 .mmap = perf_event__process_mmap,
90 .mmap2 = perf_event__process_mmap2,
91 .fork = perf_event__process_fork,
92 .exit = perf_event__exit_del_thread,
93 .attr = perf_event__process_attr,
94 .build_id = perf_event__process_build_id,
95 .ordered_events = true,
96};
97
98int build_id__sprintf(const u8 *build_id, int len, char *bf)
99{
100 char *bid = bf;
101 const u8 *raw = build_id;
102 int i;
103
104 for (i = 0; i < len; ++i) {
105 sprintf(bid, "%02x", *raw);
106 ++raw;
107 bid += 2;
108 }
109
110 return (bid - bf) + 1;
111}
112
113int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
114{
115 char notes[PATH_MAX];
116 u8 build_id[BUILD_ID_SIZE];
117 int ret;
118
119 if (!root_dir)
120 root_dir = "";
121
122 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
123
124 ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
125 if (ret < 0)
126 return ret;
127
128 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
129}
130
131int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
132{
133 u8 build_id[BUILD_ID_SIZE];
134 int ret;
135
136 ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
137 if (ret < 0)
138 return ret;
139 else if (ret != sizeof(build_id))
140 return -EINVAL;
141
142 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
143}
144
145/* asnprintf consolidates asprintf and snprintf */
146static int asnprintf(char **strp, size_t size, const char *fmt, ...)
147{
148 va_list ap;
149 int ret;
150
151 if (!strp)
152 return -EINVAL;
153
154 va_start(ap, fmt);
155 if (*strp)
156 ret = vsnprintf(*strp, size, fmt, ap);
157 else
158 ret = vasprintf(strp, fmt, ap);
159 va_end(ap);
160
161 return ret;
162}
163
164char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
165 size_t size)
166{
167 bool retry_old = true;
168
169 snprintf(bf, size, "%s/%s/%s/kallsyms",
170 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
171retry:
172 if (!access(bf, F_OK))
173 return bf;
174 if (retry_old) {
175 /* Try old style kallsyms cache */
176 snprintf(bf, size, "%s/%s/%s",
177 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
178 retry_old = false;
179 goto retry;
180 }
181
182 return NULL;
183}
184
185char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
186{
187 char *tmp = bf;
188 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
189 sbuild_id, sbuild_id + 2);
190 if (ret < 0 || (tmp && size < (unsigned int)ret))
191 return NULL;
192 return bf;
193}
194
195/* The caller is responsible to free the returned buffer. */
196char *build_id_cache__origname(const char *sbuild_id)
197{
198 char *linkname;
199 char buf[PATH_MAX];
200 char *ret = NULL, *p;
201 size_t offs = 5; /* == strlen("../..") */
202 ssize_t len;
203
204 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
205 if (!linkname)
206 return NULL;
207
208 len = readlink(linkname, buf, sizeof(buf) - 1);
209 if (len <= 0)
210 goto out;
211 buf[len] = '\0';
212
213 /* The link should be "../..<origpath>/<sbuild_id>" */
214 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
215 if (p && (p > buf + offs)) {
216 *p = '\0';
217 if (buf[offs + 1] == '[')
218 offs++; /*
219 * This is a DSO name, like [kernel.kallsyms].
220 * Skip the first '/', since this is not the
221 * cache of a regular file.
222 */
223 ret = strdup(buf + offs); /* Skip "../..[/]" */
224 }
225out:
226 free(linkname);
227 return ret;
228}
229
230/* Check if the given build_id cache is valid on current running system */
231static bool build_id_cache__valid_id(char *sbuild_id)
232{
233 char real_sbuild_id[SBUILD_ID_SIZE] = "";
234 char *pathname;
235 int ret = 0;
236 bool result = false;
237
238 pathname = build_id_cache__origname(sbuild_id);
239 if (!pathname)
240 return false;
241
242 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
243 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
244 else if (pathname[0] == '/')
245 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
246 else
247 ret = -EINVAL; /* Should we support other special DSO cache? */
248 if (ret >= 0)
249 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
250 free(pathname);
251
252 return result;
253}
254
255static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
256 bool is_debug)
257{
258 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
259 "debug" : "elf"));
260}
261
262char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
263 bool is_debug)
264{
265 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
266 bool is_vdso = dso__is_vdso((struct dso *)dso);
267 char sbuild_id[SBUILD_ID_SIZE];
268 char *linkname;
269 bool alloc = (bf == NULL);
270 int ret;
271
272 if (!dso->has_build_id)
273 return NULL;
274
275 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
276 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
277 if (!linkname)
278 return NULL;
279
280 /* Check if old style build_id cache */
281 if (is_regular_file(linkname))
282 ret = asnprintf(&bf, size, "%s", linkname);
283 else
284 ret = asnprintf(&bf, size, "%s/%s", linkname,
285 build_id_cache__basename(is_kallsyms, is_vdso,
286 is_debug));
287 if (ret < 0 || (!alloc && size < (unsigned int)ret))
288 bf = NULL;
289 free(linkname);
290
291 return bf;
292}
293
294#define dsos__for_each_with_build_id(pos, head) \
295 list_for_each_entry(pos, head, node) \
296 if (!pos->has_build_id) \
297 continue; \
298 else
299
300static int write_buildid(const char *name, size_t name_len, u8 *build_id,
301 pid_t pid, u16 misc, struct feat_fd *fd)
302{
303 int err;
304 struct perf_record_header_build_id b;
305 size_t len;
306
307 len = name_len + 1;
308 len = PERF_ALIGN(len, NAME_ALIGN);
309
310 memset(&b, 0, sizeof(b));
311 memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
312 b.pid = pid;
313 b.header.misc = misc;
314 b.header.size = sizeof(b) + len;
315
316 err = do_write(fd, &b, sizeof(b));
317 if (err < 0)
318 return err;
319
320 return write_padded(fd, name, name_len + 1, len);
321}
322
323static int machine__write_buildid_table(struct machine *machine,
324 struct feat_fd *fd)
325{
326 int err = 0;
327 struct dso *pos;
328 u16 kmisc = PERF_RECORD_MISC_KERNEL,
329 umisc = PERF_RECORD_MISC_USER;
330
331 if (!machine__is_host(machine)) {
332 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
333 umisc = PERF_RECORD_MISC_GUEST_USER;
334 }
335
336 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
337 const char *name;
338 size_t name_len;
339 bool in_kernel = false;
340
341 if (!pos->hit && !dso__is_vdso(pos))
342 continue;
343
344 if (dso__is_vdso(pos)) {
345 name = pos->short_name;
346 name_len = pos->short_name_len;
347 } else if (dso__is_kcore(pos)) {
348 name = machine->mmap_name;
349 name_len = strlen(name);
350 } else {
351 name = pos->long_name;
352 name_len = pos->long_name_len;
353 }
354
355 in_kernel = pos->kernel ||
356 is_kernel_module(name,
357 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
358 err = write_buildid(name, name_len, pos->build_id, machine->pid,
359 in_kernel ? kmisc : umisc, fd);
360 if (err)
361 break;
362 }
363
364 return err;
365}
366
367int perf_session__write_buildid_table(struct perf_session *session,
368 struct feat_fd *fd)
369{
370 struct rb_node *nd;
371 int err = machine__write_buildid_table(&session->machines.host, fd);
372
373 if (err)
374 return err;
375
376 for (nd = rb_first_cached(&session->machines.guests); nd;
377 nd = rb_next(nd)) {
378 struct machine *pos = rb_entry(nd, struct machine, rb_node);
379 err = machine__write_buildid_table(pos, fd);
380 if (err)
381 break;
382 }
383 return err;
384}
385
386static int __dsos__hit_all(struct list_head *head)
387{
388 struct dso *pos;
389
390 list_for_each_entry(pos, head, node)
391 pos->hit = true;
392
393 return 0;
394}
395
396static int machine__hit_all_dsos(struct machine *machine)
397{
398 return __dsos__hit_all(&machine->dsos.head);
399}
400
401int dsos__hit_all(struct perf_session *session)
402{
403 struct rb_node *nd;
404 int err;
405
406 err = machine__hit_all_dsos(&session->machines.host);
407 if (err)
408 return err;
409
410 for (nd = rb_first_cached(&session->machines.guests); nd;
411 nd = rb_next(nd)) {
412 struct machine *pos = rb_entry(nd, struct machine, rb_node);
413
414 err = machine__hit_all_dsos(pos);
415 if (err)
416 return err;
417 }
418
419 return 0;
420}
421
422void disable_buildid_cache(void)
423{
424 no_buildid_cache = true;
425}
426
427static bool lsdir_bid_head_filter(const char *name __maybe_unused,
428 struct dirent *d)
429{
430 return (strlen(d->d_name) == 2) &&
431 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
432}
433
434static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
435 struct dirent *d)
436{
437 int i = 0;
438 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
439 i++;
440 return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
441}
442
443struct strlist *build_id_cache__list_all(bool validonly)
444{
445 struct strlist *toplist, *linklist = NULL, *bidlist;
446 struct str_node *nd, *nd2;
447 char *topdir, *linkdir = NULL;
448 char sbuild_id[SBUILD_ID_SIZE];
449
450 /* for filename__ functions */
451 if (validonly)
452 symbol__init(NULL);
453
454 /* Open the top-level directory */
455 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
456 return NULL;
457
458 bidlist = strlist__new(NULL, NULL);
459 if (!bidlist)
460 goto out;
461
462 toplist = lsdir(topdir, lsdir_bid_head_filter);
463 if (!toplist) {
464 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
465 /* If there is no buildid cache, return an empty list */
466 if (errno == ENOENT)
467 goto out;
468 goto err_out;
469 }
470
471 strlist__for_each_entry(nd, toplist) {
472 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
473 goto err_out;
474 /* Open the lower-level directory */
475 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
476 if (!linklist) {
477 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
478 goto err_out;
479 }
480 strlist__for_each_entry(nd2, linklist) {
481 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
482 nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
483 goto err_out;
484 if (validonly && !build_id_cache__valid_id(sbuild_id))
485 continue;
486 if (strlist__add(bidlist, sbuild_id) < 0)
487 goto err_out;
488 }
489 strlist__delete(linklist);
490 zfree(&linkdir);
491 }
492
493out_free:
494 strlist__delete(toplist);
495out:
496 free(topdir);
497
498 return bidlist;
499
500err_out:
501 strlist__delete(linklist);
502 zfree(&linkdir);
503 strlist__delete(bidlist);
504 bidlist = NULL;
505 goto out_free;
506}
507
508static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
509{
510 size_t i;
511
512 for (i = 0; i < len; i++) {
513 if (!isxdigit(maybe_sbuild_id[i]))
514 return false;
515 }
516 return true;
517}
518
519/* Return the valid complete build-id */
520char *build_id_cache__complement(const char *incomplete_sbuild_id)
521{
522 struct strlist *bidlist;
523 struct str_node *nd, *cand = NULL;
524 char *sbuild_id = NULL;
525 size_t len = strlen(incomplete_sbuild_id);
526
527 if (len >= SBUILD_ID_SIZE ||
528 !str_is_build_id(incomplete_sbuild_id, len))
529 return NULL;
530
531 bidlist = build_id_cache__list_all(true);
532 if (!bidlist)
533 return NULL;
534
535 strlist__for_each_entry(nd, bidlist) {
536 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
537 continue;
538 if (cand) { /* Error: There are more than 2 candidates. */
539 cand = NULL;
540 break;
541 }
542 cand = nd;
543 }
544 if (cand)
545 sbuild_id = strdup(cand->s);
546 strlist__delete(bidlist);
547
548 return sbuild_id;
549}
550
551char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
552 struct nsinfo *nsi, bool is_kallsyms,
553 bool is_vdso)
554{
555 char *realname = (char *)name, *filename;
556 bool slash = is_kallsyms || is_vdso;
557
558 if (!slash) {
559 realname = nsinfo__realpath(name, nsi);
560 if (!realname)
561 return NULL;
562 }
563
564 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
565 is_vdso ? DSO__NAME_VDSO : realname,
566 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
567 filename = NULL;
568
569 if (!slash)
570 free(realname);
571
572 return filename;
573}
574
575int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
576 struct strlist **result)
577{
578 char *dir_name;
579 int ret = 0;
580
581 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
582 if (!dir_name)
583 return -ENOMEM;
584
585 *result = lsdir(dir_name, lsdir_no_dot_filter);
586 if (!*result)
587 ret = -errno;
588 free(dir_name);
589
590 return ret;
591}
592
593#if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
594static int build_id_cache__add_sdt_cache(const char *sbuild_id,
595 const char *realname,
596 struct nsinfo *nsi)
597{
598 struct probe_cache *cache;
599 int ret;
600 struct nscookie nsc;
601
602 cache = probe_cache__new(sbuild_id, nsi);
603 if (!cache)
604 return -1;
605
606 nsinfo__mountns_enter(nsi, &nsc);
607 ret = probe_cache__scan_sdt(cache, realname);
608 nsinfo__mountns_exit(&nsc);
609 if (ret >= 0) {
610 pr_debug4("Found %d SDTs in %s\n", ret, realname);
611 if (probe_cache__commit(cache) < 0)
612 ret = -1;
613 }
614 probe_cache__delete(cache);
615 return ret;
616}
617#else
618#define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
619#endif
620
621static char *build_id_cache__find_debug(const char *sbuild_id,
622 struct nsinfo *nsi)
623{
624 char *realname = NULL;
625 char *debugfile;
626 struct nscookie nsc;
627 size_t len = 0;
628
629 debugfile = calloc(1, PATH_MAX);
630 if (!debugfile)
631 goto out;
632
633 len = __symbol__join_symfs(debugfile, PATH_MAX,
634 "/usr/lib/debug/.build-id/");
635 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
636 sbuild_id + 2);
637
638 nsinfo__mountns_enter(nsi, &nsc);
639 realname = realpath(debugfile, NULL);
640 if (realname && access(realname, R_OK))
641 zfree(&realname);
642 nsinfo__mountns_exit(&nsc);
643
644#ifdef HAVE_DEBUGINFOD_SUPPORT
645 if (realname == NULL) {
646 debuginfod_client* c = debuginfod_begin();
647 if (c != NULL) {
648 int fd = debuginfod_find_debuginfo(c,
649 (const unsigned char*)sbuild_id, 0,
650 &realname);
651 if (fd >= 0)
652 close(fd); /* retaining reference by realname */
653 debuginfod_end(c);
654 }
655 }
656#endif
657
658out:
659 free(debugfile);
660 return realname;
661}
662
663int build_id_cache__add_s(const char *sbuild_id, const char *name,
664 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
665{
666 const size_t size = PATH_MAX;
667 char *realname = NULL, *filename = NULL, *dir_name = NULL,
668 *linkname = zalloc(size), *tmp;
669 char *debugfile = NULL;
670 int err = -1;
671
672 if (!is_kallsyms) {
673 if (!is_vdso)
674 realname = nsinfo__realpath(name, nsi);
675 else
676 realname = realpath(name, NULL);
677 if (!realname)
678 goto out_free;
679 }
680
681 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
682 is_vdso);
683 if (!dir_name)
684 goto out_free;
685
686 /* Remove old style build-id cache */
687 if (is_regular_file(dir_name))
688 if (unlink(dir_name))
689 goto out_free;
690
691 if (mkdir_p(dir_name, 0755))
692 goto out_free;
693
694 /* Save the allocated buildid dirname */
695 if (asprintf(&filename, "%s/%s", dir_name,
696 build_id_cache__basename(is_kallsyms, is_vdso,
697 false)) < 0) {
698 filename = NULL;
699 goto out_free;
700 }
701
702 if (access(filename, F_OK)) {
703 if (is_kallsyms) {
704 if (copyfile("/proc/kallsyms", filename))
705 goto out_free;
706 } else if (nsi && nsi->need_setns) {
707 if (copyfile_ns(name, filename, nsi))
708 goto out_free;
709 } else if (link(realname, filename) && errno != EEXIST &&
710 copyfile(name, filename))
711 goto out_free;
712 }
713
714 /* Some binaries are stripped, but have .debug files with their symbol
715 * table. Check to see if we can locate one of those, since the elf
716 * file itself may not be very useful to users of our tools without a
717 * symtab.
718 */
719 if (!is_kallsyms && !is_vdso &&
720 strncmp(".ko", name + strlen(name) - 3, 3)) {
721 debugfile = build_id_cache__find_debug(sbuild_id, nsi);
722 if (debugfile) {
723 zfree(&filename);
724 if (asprintf(&filename, "%s/%s", dir_name,
725 build_id_cache__basename(false, false, true)) < 0) {
726 filename = NULL;
727 goto out_free;
728 }
729 if (access(filename, F_OK)) {
730 if (nsi && nsi->need_setns) {
731 if (copyfile_ns(debugfile, filename,
732 nsi))
733 goto out_free;
734 } else if (link(debugfile, filename) &&
735 errno != EEXIST &&
736 copyfile(debugfile, filename))
737 goto out_free;
738 }
739 }
740 }
741
742 if (!build_id_cache__linkname(sbuild_id, linkname, size))
743 goto out_free;
744 tmp = strrchr(linkname, '/');
745 *tmp = '\0';
746
747 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
748 goto out_free;
749
750 *tmp = '/';
751 tmp = dir_name + strlen(buildid_dir) - 5;
752 memcpy(tmp, "../..", 5);
753
754 if (symlink(tmp, linkname) == 0)
755 err = 0;
756
757 /* Update SDT cache : error is just warned */
758 if (realname &&
759 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
760 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
761
762out_free:
763 if (!is_kallsyms)
764 free(realname);
765 free(filename);
766 free(debugfile);
767 free(dir_name);
768 free(linkname);
769 return err;
770}
771
772static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
773 const char *name, struct nsinfo *nsi,
774 bool is_kallsyms, bool is_vdso)
775{
776 char sbuild_id[SBUILD_ID_SIZE];
777
778 build_id__sprintf(build_id, build_id_size, sbuild_id);
779
780 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
781 is_vdso);
782}
783
784bool build_id_cache__cached(const char *sbuild_id)
785{
786 bool ret = false;
787 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
788
789 if (filename && !access(filename, F_OK))
790 ret = true;
791 free(filename);
792
793 return ret;
794}
795
796int build_id_cache__remove_s(const char *sbuild_id)
797{
798 const size_t size = PATH_MAX;
799 char *filename = zalloc(size),
800 *linkname = zalloc(size), *tmp;
801 int err = -1;
802
803 if (filename == NULL || linkname == NULL)
804 goto out_free;
805
806 if (!build_id_cache__linkname(sbuild_id, linkname, size))
807 goto out_free;
808
809 if (access(linkname, F_OK))
810 goto out_free;
811
812 if (readlink(linkname, filename, size - 1) < 0)
813 goto out_free;
814
815 if (unlink(linkname))
816 goto out_free;
817
818 /*
819 * Since the link is relative, we must make it absolute:
820 */
821 tmp = strrchr(linkname, '/') + 1;
822 snprintf(tmp, size - (tmp - linkname), "%s", filename);
823
824 if (rm_rf(linkname))
825 goto out_free;
826
827 err = 0;
828out_free:
829 free(filename);
830 free(linkname);
831 return err;
832}
833
834static int dso__cache_build_id(struct dso *dso, struct machine *machine)
835{
836 bool is_kallsyms = dso__is_kallsyms(dso);
837 bool is_vdso = dso__is_vdso(dso);
838 const char *name = dso->long_name;
839
840 if (dso__is_kcore(dso)) {
841 is_kallsyms = true;
842 name = machine->mmap_name;
843 }
844 return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
845 dso->nsinfo, is_kallsyms, is_vdso);
846}
847
848static int __dsos__cache_build_ids(struct list_head *head,
849 struct machine *machine)
850{
851 struct dso *pos;
852 int err = 0;
853
854 dsos__for_each_with_build_id(pos, head)
855 if (dso__cache_build_id(pos, machine))
856 err = -1;
857
858 return err;
859}
860
861static int machine__cache_build_ids(struct machine *machine)
862{
863 return __dsos__cache_build_ids(&machine->dsos.head, machine);
864}
865
866int perf_session__cache_build_ids(struct perf_session *session)
867{
868 struct rb_node *nd;
869 int ret;
870
871 if (no_buildid_cache)
872 return 0;
873
874 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
875 return -1;
876
877 ret = machine__cache_build_ids(&session->machines.host);
878
879 for (nd = rb_first_cached(&session->machines.guests); nd;
880 nd = rb_next(nd)) {
881 struct machine *pos = rb_entry(nd, struct machine, rb_node);
882 ret |= machine__cache_build_ids(pos);
883 }
884 return ret ? -1 : 0;
885}
886
887static bool machine__read_build_ids(struct machine *machine, bool with_hits)
888{
889 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
890}
891
892bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
893{
894 struct rb_node *nd;
895 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
896
897 for (nd = rb_first_cached(&session->machines.guests); nd;
898 nd = rb_next(nd)) {
899 struct machine *pos = rb_entry(nd, struct machine, rb_node);
900 ret |= machine__read_build_ids(pos, with_hits);
901 }
902
903 return ret;
904}