xref: /linux/tools/perf/util/dso.c (revision c7decec2f2d2ab0366567f9e30c0e1418cece43f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <asm/bug.h>
3 #include <linux/kernel.h>
4 #include <linux/string.h>
5 #include <linux/zalloc.h>
6 #include <sys/time.h>
7 #include <sys/resource.h>
8 #include <sys/types.h>
9 #include <sys/stat.h>
10 #include <unistd.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <stdlib.h>
14 #ifdef HAVE_LIBBPF_SUPPORT
15 #include <bpf/libbpf.h>
16 #include "bpf-event.h"
17 #include "bpf-utils.h"
18 #endif
19 #include "compress.h"
20 #include "env.h"
21 #include "namespaces.h"
22 #include "path.h"
23 #include "map.h"
24 #include "symbol.h"
25 #include "srcline.h"
26 #include "dso.h"
27 #include "dsos.h"
28 #include "machine.h"
29 #include "auxtrace.h"
30 #include "util.h" /* O_CLOEXEC for older systems */
31 #include "debug.h"
32 #include "string2.h"
33 #include "vdso.h"
34 #include "annotate-data.h"
35 #include "libdw.h"
36 
37 static const char * const debuglink_paths[] = {
38 	"%.0s%s",
39 	"%s/%s",
40 	"%s/.debug/%s",
41 	"/usr/lib/debug%s/%s"
42 };
43 
dso__set_nsinfo(struct dso * dso,struct nsinfo * nsi)44 void dso__set_nsinfo(struct dso *dso, struct nsinfo *nsi)
45 {
46 	nsinfo__put(RC_CHK_ACCESS(dso)->nsinfo);
47 	RC_CHK_ACCESS(dso)->nsinfo = nsi;
48 }
49 
dso__symtab_origin(const struct dso * dso)50 char dso__symtab_origin(const struct dso *dso)
51 {
52 	static const char origin[] = {
53 		[DSO_BINARY_TYPE__KALLSYMS]			= 'k',
54 		[DSO_BINARY_TYPE__VMLINUX]			= 'v',
55 		[DSO_BINARY_TYPE__JAVA_JIT]			= 'j',
56 		[DSO_BINARY_TYPE__DEBUGLINK]			= 'l',
57 		[DSO_BINARY_TYPE__BUILD_ID_CACHE]		= 'B',
58 		[DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO]	= 'D',
59 		[DSO_BINARY_TYPE__FEDORA_DEBUGINFO]		= 'f',
60 		[DSO_BINARY_TYPE__UBUNTU_DEBUGINFO]		= 'u',
61 		[DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO]	= 'x',
62 		[DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO]	= 'o',
63 		[DSO_BINARY_TYPE__BUILDID_DEBUGINFO]		= 'b',
64 		[DSO_BINARY_TYPE__SYSTEM_PATH_DSO]		= 'd',
65 		[DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE]		= 'K',
66 		[DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP]	= 'm',
67 		[DSO_BINARY_TYPE__GUEST_KALLSYMS]		= 'g',
68 		[DSO_BINARY_TYPE__GUEST_KMODULE]		= 'G',
69 		[DSO_BINARY_TYPE__GUEST_KMODULE_COMP]		= 'M',
70 		[DSO_BINARY_TYPE__GUEST_VMLINUX]		= 'V',
71 		[DSO_BINARY_TYPE__GNU_DEBUGDATA]		= 'n',
72 	};
73 
74 	if (dso == NULL || dso__symtab_type(dso) == DSO_BINARY_TYPE__NOT_FOUND)
75 		return '!';
76 	return origin[dso__symtab_type(dso)];
77 }
78 
dso__is_object_file(const struct dso * dso)79 bool dso__is_object_file(const struct dso *dso)
80 {
81 	switch (dso__binary_type(dso)) {
82 	case DSO_BINARY_TYPE__KALLSYMS:
83 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
84 	case DSO_BINARY_TYPE__JAVA_JIT:
85 	case DSO_BINARY_TYPE__BPF_PROG_INFO:
86 	case DSO_BINARY_TYPE__BPF_IMAGE:
87 	case DSO_BINARY_TYPE__OOL:
88 		return false;
89 	case DSO_BINARY_TYPE__VMLINUX:
90 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
91 	case DSO_BINARY_TYPE__DEBUGLINK:
92 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
93 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
94 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
95 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
96 	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
97 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
98 	case DSO_BINARY_TYPE__GNU_DEBUGDATA:
99 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
100 	case DSO_BINARY_TYPE__GUEST_KMODULE:
101 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
102 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
103 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
104 	case DSO_BINARY_TYPE__KCORE:
105 	case DSO_BINARY_TYPE__GUEST_KCORE:
106 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
107 	case DSO_BINARY_TYPE__NOT_FOUND:
108 	default:
109 		return true;
110 	}
111 }
112 
dso__read_binary_type_filename(const struct dso * dso,enum dso_binary_type type,const char * root_dir,char * filename,size_t size)113 int dso__read_binary_type_filename(const struct dso *dso,
114 				   enum dso_binary_type type,
115 				   const char *root_dir, char *filename, size_t size)
116 {
117 	char build_id_hex[SBUILD_ID_SIZE];
118 	int ret = 0;
119 	size_t len;
120 
121 	switch (type) {
122 	case DSO_BINARY_TYPE__DEBUGLINK:
123 	{
124 		const char *last_slash;
125 		char dso_dir[PATH_MAX];
126 		char symfile[PATH_MAX];
127 		unsigned int i;
128 
129 		len = __symbol__join_symfs(filename, size, dso__long_name(dso));
130 		last_slash = filename + len;
131 		while (last_slash != filename && *last_slash != '/')
132 			last_slash--;
133 
134 		strncpy(dso_dir, filename, last_slash - filename);
135 		dso_dir[last_slash-filename] = '\0';
136 
137 		if (!is_regular_file(filename)) {
138 			ret = -1;
139 			break;
140 		}
141 
142 		ret = filename__read_debuglink(filename, symfile, PATH_MAX);
143 		if (ret)
144 			break;
145 
146 		/* Check predefined locations where debug file might reside */
147 		ret = -1;
148 		for (i = 0; i < ARRAY_SIZE(debuglink_paths); i++) {
149 			snprintf(filename, size,
150 					debuglink_paths[i], dso_dir, symfile);
151 			if (is_regular_file(filename)) {
152 				ret = 0;
153 				break;
154 			}
155 		}
156 
157 		break;
158 	}
159 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
160 		if (dso__build_id_filename(dso, filename, size, false) == NULL)
161 			ret = -1;
162 		break;
163 
164 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
165 		if (dso__build_id_filename(dso, filename, size, true) == NULL)
166 			ret = -1;
167 		break;
168 
169 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
170 		len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
171 		snprintf(filename + len, size - len, "%s.debug", dso__long_name(dso));
172 		break;
173 
174 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
175 		len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
176 		snprintf(filename + len, size - len, "%s", dso__long_name(dso));
177 		break;
178 
179 	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
180 		/*
181 		 * Ubuntu can mixup /usr/lib with /lib, putting debuginfo in
182 		 * /usr/lib/debug/lib when it is expected to be in
183 		 * /usr/lib/debug/usr/lib
184 		 */
185 		if (strlen(dso__long_name(dso)) < 9 ||
186 		    strncmp(dso__long_name(dso), "/usr/lib/", 9)) {
187 			ret = -1;
188 			break;
189 		}
190 		len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
191 		snprintf(filename + len, size - len, "%s", dso__long_name(dso) + 4);
192 		break;
193 
194 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
195 	{
196 		const char *last_slash;
197 		size_t dir_size;
198 
199 		last_slash = dso__long_name(dso) + dso__long_name_len(dso);
200 		while (last_slash != dso__long_name(dso) && *last_slash != '/')
201 			last_slash--;
202 
203 		len = __symbol__join_symfs(filename, size, "");
204 		dir_size = last_slash - dso__long_name(dso) + 2;
205 		if (dir_size > (size - len)) {
206 			ret = -1;
207 			break;
208 		}
209 		len += scnprintf(filename + len, dir_size, "%s",  dso__long_name(dso));
210 		len += scnprintf(filename + len , size - len, ".debug%s",
211 								last_slash);
212 		break;
213 	}
214 
215 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
216 		if (!dso__has_build_id(dso)) {
217 			ret = -1;
218 			break;
219 		}
220 
221 		build_id__snprintf(dso__bid(dso), build_id_hex, sizeof(build_id_hex));
222 		len = __symbol__join_symfs(filename, size, "/usr/lib/debug/.build-id/");
223 		snprintf(filename + len, size - len, "%.2s/%s.debug",
224 			 build_id_hex, build_id_hex + 2);
225 		break;
226 
227 	case DSO_BINARY_TYPE__VMLINUX:
228 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
229 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
230 	case DSO_BINARY_TYPE__GNU_DEBUGDATA:
231 		__symbol__join_symfs(filename, size, dso__long_name(dso));
232 		break;
233 
234 	case DSO_BINARY_TYPE__GUEST_KMODULE:
235 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
236 		path__join3(filename, size, symbol_conf.symfs,
237 			    root_dir, dso__long_name(dso));
238 		break;
239 
240 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
241 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
242 		__symbol__join_symfs(filename, size, dso__long_name(dso));
243 		break;
244 
245 	case DSO_BINARY_TYPE__KCORE:
246 	case DSO_BINARY_TYPE__GUEST_KCORE:
247 		snprintf(filename, size, "%s", dso__long_name(dso));
248 		break;
249 
250 	default:
251 	case DSO_BINARY_TYPE__KALLSYMS:
252 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
253 	case DSO_BINARY_TYPE__JAVA_JIT:
254 	case DSO_BINARY_TYPE__BPF_PROG_INFO:
255 	case DSO_BINARY_TYPE__BPF_IMAGE:
256 	case DSO_BINARY_TYPE__OOL:
257 	case DSO_BINARY_TYPE__NOT_FOUND:
258 		ret = -1;
259 		break;
260 	}
261 
262 	return ret;
263 }
264 
265 enum {
266 	COMP_ID__NONE = 0,
267 };
268 
269 static const struct {
270 	const char *fmt;
271 	int (*decompress)(const char *input, int output);
272 	bool (*is_compressed)(const char *input);
273 } compressions[] = {
274 	[COMP_ID__NONE] = { .fmt = NULL, },
275 #ifdef HAVE_ZLIB_SUPPORT
276 	{ "gz", gzip_decompress_to_file, gzip_is_compressed },
277 #endif
278 #ifdef HAVE_LZMA_SUPPORT
279 	{ "xz", lzma_decompress_to_file, lzma_is_compressed },
280 #endif
281 	{ NULL, NULL, NULL },
282 };
283 
is_supported_compression(const char * ext)284 static int is_supported_compression(const char *ext)
285 {
286 	unsigned i;
287 
288 	for (i = 1; compressions[i].fmt; i++) {
289 		if (!strcmp(ext, compressions[i].fmt))
290 			return i;
291 	}
292 	return COMP_ID__NONE;
293 }
294 
is_kernel_module(const char * pathname,int cpumode)295 bool is_kernel_module(const char *pathname, int cpumode)
296 {
297 	struct kmod_path m;
298 	int mode = cpumode & PERF_RECORD_MISC_CPUMODE_MASK;
299 
300 	WARN_ONCE(mode != cpumode,
301 		  "Internal error: passing unmasked cpumode (%x) to is_kernel_module",
302 		  cpumode);
303 
304 	switch (mode) {
305 	case PERF_RECORD_MISC_USER:
306 	case PERF_RECORD_MISC_HYPERVISOR:
307 	case PERF_RECORD_MISC_GUEST_USER:
308 		return false;
309 	/* Treat PERF_RECORD_MISC_CPUMODE_UNKNOWN as kernel */
310 	default:
311 		if (kmod_path__parse(&m, pathname)) {
312 			pr_err("Failed to check whether %s is a kernel module or not. Assume it is.",
313 					pathname);
314 			return true;
315 		}
316 	}
317 
318 	return m.kmod;
319 }
320 
dso__needs_decompress(struct dso * dso)321 bool dso__needs_decompress(struct dso *dso)
322 {
323 	return dso__symtab_type(dso) == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
324 		dso__symtab_type(dso) == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
325 }
326 
filename__decompress(const char * name,char * pathname,size_t len,int comp,int * err)327 int filename__decompress(const char *name, char *pathname,
328 			 size_t len, int comp, int *err)
329 {
330 	char tmpbuf[] = KMOD_DECOMP_NAME;
331 	int fd = -1;
332 
333 	/*
334 	 * We have proper compression id for DSO and yet the file
335 	 * behind the 'name' can still be plain uncompressed object.
336 	 *
337 	 * The reason is behind the logic we open the DSO object files,
338 	 * when we try all possible 'debug' objects until we find the
339 	 * data. So even if the DSO is represented by 'krava.xz' module,
340 	 * we can end up here opening ~/.debug/....23432432/debug' file
341 	 * which is not compressed.
342 	 *
343 	 * To keep this transparent, we detect this and return the file
344 	 * descriptor to the uncompressed file.
345 	 */
346 	if (!compressions[comp].is_compressed(name))
347 		return open(name, O_RDONLY);
348 
349 	fd = mkstemp(tmpbuf);
350 	if (fd < 0) {
351 		*err = errno;
352 		return -1;
353 	}
354 
355 	if (compressions[comp].decompress(name, fd)) {
356 		*err = DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE;
357 		close(fd);
358 		fd = -1;
359 	}
360 
361 	if (!pathname || (fd < 0))
362 		unlink(tmpbuf);
363 
364 	if (pathname && (fd >= 0))
365 		strlcpy(pathname, tmpbuf, len);
366 
367 	return fd;
368 }
369 
decompress_kmodule(struct dso * dso,const char * name,char * pathname,size_t len)370 static int decompress_kmodule(struct dso *dso, const char *name,
371 			      char *pathname, size_t len)
372 {
373 	if (!dso__needs_decompress(dso))
374 		return -1;
375 
376 	if (dso__comp(dso) == COMP_ID__NONE)
377 		return -1;
378 
379 	return filename__decompress(name, pathname, len, dso__comp(dso), dso__load_errno(dso));
380 }
381 
dso__decompress_kmodule_fd(struct dso * dso,const char * name)382 int dso__decompress_kmodule_fd(struct dso *dso, const char *name)
383 {
384 	return decompress_kmodule(dso, name, NULL, 0);
385 }
386 
dso__decompress_kmodule_path(struct dso * dso,const char * name,char * pathname,size_t len)387 int dso__decompress_kmodule_path(struct dso *dso, const char *name,
388 				 char *pathname, size_t len)
389 {
390 	int fd = decompress_kmodule(dso, name, pathname, len);
391 
392 	close(fd);
393 	return fd >= 0 ? 0 : -1;
394 }
395 
396 /*
397  * Parses kernel module specified in @path and updates
398  * @m argument like:
399  *
400  *    @comp - true if @path contains supported compression suffix,
401  *            false otherwise
402  *    @kmod - true if @path contains '.ko' suffix in right position,
403  *            false otherwise
404  *    @name - if (@alloc_name && @kmod) is true, it contains strdup-ed base name
405  *            of the kernel module without suffixes, otherwise strudup-ed
406  *            base name of @path
407  *    @ext  - if (@alloc_ext && @comp) is true, it contains strdup-ed string
408  *            the compression suffix
409  *
410  * Returns 0 if there's no strdup error, -ENOMEM otherwise.
411  */
__kmod_path__parse(struct kmod_path * m,const char * path,bool alloc_name)412 int __kmod_path__parse(struct kmod_path *m, const char *path,
413 		       bool alloc_name)
414 {
415 	const char *name = strrchr(path, '/');
416 	const char *ext  = strrchr(path, '.');
417 	bool is_simple_name = false;
418 
419 	memset(m, 0x0, sizeof(*m));
420 	name = name ? name + 1 : path;
421 
422 	/*
423 	 * '.' is also a valid character for module name. For example:
424 	 * [aaa.bbb] is a valid module name. '[' should have higher
425 	 * priority than '.ko' suffix.
426 	 *
427 	 * The kernel names are from machine__mmap_name. Such
428 	 * name should belong to kernel itself, not kernel module.
429 	 */
430 	if (name[0] == '[') {
431 		is_simple_name = true;
432 		if ((strncmp(name, "[kernel.kallsyms]", 17) == 0) ||
433 		    (strncmp(name, "[guest.kernel.kallsyms", 22) == 0) ||
434 		    (strncmp(name, "[vdso]", 6) == 0) ||
435 		    (strncmp(name, "[vdso32]", 8) == 0) ||
436 		    (strncmp(name, "[vdsox32]", 9) == 0) ||
437 		    (strncmp(name, "[vsyscall]", 10) == 0)) {
438 			m->kmod = false;
439 
440 		} else
441 			m->kmod = true;
442 	}
443 
444 	/* No extension, just return name. */
445 	if ((ext == NULL) || is_simple_name) {
446 		if (alloc_name) {
447 			m->name = strdup(name);
448 			return m->name ? 0 : -ENOMEM;
449 		}
450 		return 0;
451 	}
452 
453 	m->comp = is_supported_compression(ext + 1);
454 	if (m->comp > COMP_ID__NONE)
455 		ext -= 3;
456 
457 	/* Check .ko extension only if there's enough name left. */
458 	if (ext > name)
459 		m->kmod = !strncmp(ext, ".ko", 3);
460 
461 	if (alloc_name) {
462 		if (m->kmod) {
463 			if (asprintf(&m->name, "[%.*s]", (int) (ext - name), name) == -1)
464 				return -ENOMEM;
465 		} else {
466 			if (asprintf(&m->name, "%s", name) == -1)
467 				return -ENOMEM;
468 		}
469 
470 		strreplace(m->name, '-', '_');
471 	}
472 
473 	return 0;
474 }
475 
dso__set_module_info(struct dso * dso,struct kmod_path * m,struct machine * machine)476 void dso__set_module_info(struct dso *dso, struct kmod_path *m,
477 			  struct machine *machine)
478 {
479 	if (machine__is_host(machine))
480 		dso__set_symtab_type(dso, DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE);
481 	else
482 		dso__set_symtab_type(dso, DSO_BINARY_TYPE__GUEST_KMODULE);
483 
484 	/* _KMODULE_COMP should be next to _KMODULE */
485 	if (m->kmod && m->comp) {
486 		dso__set_symtab_type(dso, dso__symtab_type(dso) + 1);
487 		dso__set_comp(dso, m->comp);
488 	}
489 
490 	dso__set_is_kmod(dso);
491 	dso__set_short_name(dso, strdup(m->name), true);
492 }
493 
494 /*
495  * Global list of open DSOs and the counter.
496  */
497 struct mutex _dso__data_open_lock;
498 static LIST_HEAD(dso__data_open);
499 static long dso__data_open_cnt GUARDED_BY(_dso__data_open_lock);
500 
dso__data_open_lock_init(void)501 static void dso__data_open_lock_init(void)
502 {
503 	mutex_init(&_dso__data_open_lock);
504 }
505 
dso__data_open_lock(void)506 static struct mutex *dso__data_open_lock(void) LOCK_RETURNED(_dso__data_open_lock)
507 {
508 	static pthread_once_t data_open_lock_once = PTHREAD_ONCE_INIT;
509 
510 	pthread_once(&data_open_lock_once, dso__data_open_lock_init);
511 
512 	return &_dso__data_open_lock;
513 }
514 
dso__list_add(struct dso * dso)515 static void dso__list_add(struct dso *dso) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
516 {
517 	list_add_tail(&dso__data(dso)->open_entry, &dso__data_open);
518 #ifdef REFCNT_CHECKING
519 	dso__data(dso)->dso = dso__get(dso);
520 #endif
521 	/* Assume the dso is part of dsos, hence the optional reference count above. */
522 	assert(dso__dsos(dso));
523 	dso__data_open_cnt++;
524 }
525 
dso__list_del(struct dso * dso)526 static void dso__list_del(struct dso *dso) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
527 {
528 	list_del_init(&dso__data(dso)->open_entry);
529 #ifdef REFCNT_CHECKING
530 	mutex_unlock(dso__data_open_lock());
531 	dso__put(dso__data(dso)->dso);
532 	mutex_lock(dso__data_open_lock());
533 #endif
534 	WARN_ONCE(dso__data_open_cnt <= 0,
535 		  "DSO data fd counter out of bounds.");
536 	dso__data_open_cnt--;
537 }
538 
539 static void close_first_dso(void);
540 
do_open(char * name)541 static int do_open(char *name) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
542 {
543 	do {
544 		int fd = open(name, O_RDONLY|O_CLOEXEC);
545 
546 		if (fd >= 0)
547 			return fd;
548 
549 		pr_debug("dso open failed: %m\n");
550 		if (!dso__data_open_cnt || errno != EMFILE)
551 			break;
552 
553 		close_first_dso();
554 	} while (1);
555 
556 	return -1;
557 }
558 
dso__filename_with_chroot(const struct dso * dso,const char * filename)559 char *dso__filename_with_chroot(const struct dso *dso, const char *filename)
560 {
561 	return filename_with_chroot(nsinfo__pid(dso__nsinfo_const(dso)), filename);
562 }
563 
dso__get_filename(struct dso * dso,const char * root_dir,bool * decomp)564 static char *dso__get_filename(struct dso *dso, const char *root_dir,
565 			       bool *decomp)
566 {
567 	char *name = malloc(PATH_MAX);
568 
569 	*decomp = false;
570 
571 	if (name == NULL)
572 		return NULL;
573 
574 	if (dso__read_binary_type_filename(dso, dso__binary_type(dso),
575 					    root_dir, name, PATH_MAX))
576 		goto out;
577 
578 	if (!is_regular_file(name)) {
579 		char *new_name;
580 
581 		if (errno != ENOENT || dso__nsinfo(dso) == NULL)
582 			goto out;
583 
584 		new_name = dso__filename_with_chroot(dso, name);
585 		if (!new_name)
586 			goto out;
587 
588 		free(name);
589 		name = new_name;
590 	}
591 
592 	if (dso__needs_decompress(dso)) {
593 		char newpath[KMOD_DECOMP_LEN];
594 		size_t len = sizeof(newpath);
595 
596 		if (dso__decompress_kmodule_path(dso, name, newpath, len) < 0) {
597 			errno = *dso__load_errno(dso);
598 			goto out;
599 		}
600 
601 		*decomp = true;
602 		strcpy(name, newpath);
603 	}
604 	return name;
605 
606 out:
607 	free(name);
608 	return NULL;
609 }
610 
__open_dso(struct dso * dso,struct machine * machine)611 static int __open_dso(struct dso *dso, struct machine *machine)
612 	EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
613 {
614 	int fd = -EINVAL;
615 	char *name;
616 	bool decomp = false;
617 
618 	mutex_lock(dso__lock(dso));
619 
620 	name = dso__get_filename(dso, machine ? machine->root_dir : "", &decomp);
621 	if (name)
622 		fd = do_open(name);
623 	else
624 		fd = -errno;
625 
626 	if (decomp)
627 		unlink(name);
628 
629 	mutex_unlock(dso__lock(dso));
630 	free(name);
631 	return fd;
632 }
633 
634 static void check_data_close(void);
635 
636 /**
637  * dso_close - Open DSO data file
638  * @dso: dso object
639  *
640  * Open @dso's data file descriptor and updates
641  * list/count of open DSO objects.
642  */
open_dso(struct dso * dso,struct machine * machine)643 static int open_dso(struct dso *dso, struct machine *machine)
644 	EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
645 {
646 	int fd;
647 	struct nscookie nsc;
648 
649 	if (dso__binary_type(dso) != DSO_BINARY_TYPE__BUILD_ID_CACHE) {
650 		mutex_lock(dso__lock(dso));
651 		nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
652 		mutex_unlock(dso__lock(dso));
653 	}
654 	fd = __open_dso(dso, machine);
655 	if (dso__binary_type(dso) != DSO_BINARY_TYPE__BUILD_ID_CACHE)
656 		nsinfo__mountns_exit(&nsc);
657 
658 	if (fd >= 0) {
659 		dso__list_add(dso);
660 		/*
661 		 * Check if we crossed the allowed number
662 		 * of opened DSOs and close one if needed.
663 		 */
664 		check_data_close();
665 	}
666 
667 	return fd;
668 }
669 
close_data_fd(struct dso * dso)670 static void close_data_fd(struct dso *dso) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
671 {
672 	if (dso__data(dso)->fd >= 0) {
673 		close(dso__data(dso)->fd);
674 		dso__data(dso)->fd = -1;
675 		dso__data(dso)->file_size = 0;
676 		dso__list_del(dso);
677 	}
678 }
679 
680 /**
681  * dso_close - Close DSO data file
682  * @dso: dso object
683  *
684  * Close @dso's data file descriptor and updates
685  * list/count of open DSO objects.
686  */
close_dso(struct dso * dso)687 static void close_dso(struct dso *dso) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
688 {
689 	close_data_fd(dso);
690 }
691 
close_first_dso(void)692 static void close_first_dso(void) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
693 {
694 	struct dso_data *dso_data;
695 	struct dso *dso;
696 
697 	dso_data = list_first_entry(&dso__data_open, struct dso_data, open_entry);
698 #ifdef REFCNT_CHECKING
699 	dso = dso_data->dso;
700 #else
701 	dso = container_of(dso_data, struct dso, data);
702 #endif
703 	close_dso(dso);
704 }
705 
get_fd_limit(void)706 static rlim_t get_fd_limit(void)
707 {
708 	struct rlimit l;
709 	rlim_t limit = 0;
710 
711 	/* Allow half of the current open fd limit. */
712 	if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
713 		if (l.rlim_cur == RLIM_INFINITY)
714 			limit = l.rlim_cur;
715 		else
716 			limit = l.rlim_cur / 2;
717 	} else {
718 		pr_err("failed to get fd limit\n");
719 		limit = 1;
720 	}
721 
722 	return limit;
723 }
724 
725 static rlim_t fd_limit;
726 
727 /*
728  * Used only by tests/dso-data.c to reset the environment
729  * for tests. I dont expect we should change this during
730  * standard runtime.
731  */
reset_fd_limit(void)732 void reset_fd_limit(void)
733 {
734 	fd_limit = 0;
735 }
736 
may_cache_fd(void)737 static bool may_cache_fd(void) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
738 {
739 	if (!fd_limit)
740 		fd_limit = get_fd_limit();
741 
742 	if (fd_limit == RLIM_INFINITY)
743 		return true;
744 
745 	return fd_limit > (rlim_t) dso__data_open_cnt;
746 }
747 
748 /*
749  * Check and close LRU dso if we crossed allowed limit
750  * for opened dso file descriptors. The limit is half
751  * of the RLIMIT_NOFILE files opened.
752 */
check_data_close(void)753 static void check_data_close(void) EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
754 {
755 	bool cache_fd = may_cache_fd();
756 
757 	if (!cache_fd)
758 		close_first_dso();
759 }
760 
761 /**
762  * dso__data_close - Close DSO data file
763  * @dso: dso object
764  *
765  * External interface to close @dso's data file descriptor.
766  */
dso__data_close(struct dso * dso)767 void dso__data_close(struct dso *dso)
768 {
769 	mutex_lock(dso__data_open_lock());
770 	close_dso(dso);
771 	mutex_unlock(dso__data_open_lock());
772 }
773 
try_to_open_dso(struct dso * dso,struct machine * machine)774 static void try_to_open_dso(struct dso *dso, struct machine *machine)
775 	EXCLUSIVE_LOCKS_REQUIRED(_dso__data_open_lock)
776 {
777 	enum dso_binary_type binary_type_data[] = {
778 		DSO_BINARY_TYPE__BUILD_ID_CACHE,
779 		DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
780 		DSO_BINARY_TYPE__NOT_FOUND,
781 	};
782 	int i = 0;
783 	struct dso_data *dso_data = dso__data(dso);
784 
785 	if (dso_data->fd >= 0)
786 		return;
787 
788 	if (dso__binary_type(dso) != DSO_BINARY_TYPE__NOT_FOUND) {
789 		dso_data->fd = open_dso(dso, machine);
790 		goto out;
791 	}
792 
793 	do {
794 		dso__set_binary_type(dso, binary_type_data[i++]);
795 
796 		dso_data->fd = open_dso(dso, machine);
797 		if (dso_data->fd >= 0)
798 			goto out;
799 
800 	} while (dso__binary_type(dso) != DSO_BINARY_TYPE__NOT_FOUND);
801 out:
802 	if (dso_data->fd >= 0)
803 		dso_data->status = DSO_DATA_STATUS_OK;
804 	else
805 		dso_data->status = DSO_DATA_STATUS_ERROR;
806 }
807 
808 /**
809  * dso__data_get_fd - Get dso's data file descriptor
810  * @dso: dso object
811  * @machine: machine object
812  *
813  * External interface to find dso's file, open it and
814  * returns file descriptor.  It should be paired with
815  * dso__data_put_fd() if it returns non-negative value.
816  */
dso__data_get_fd(struct dso * dso,struct machine * machine,int * fd)817 bool dso__data_get_fd(struct dso *dso, struct machine *machine, int *fd)
818 {
819 	*fd = -1;
820 	if (dso__data(dso)->status == DSO_DATA_STATUS_ERROR)
821 		return false;
822 
823 	mutex_lock(dso__data_open_lock());
824 
825 	try_to_open_dso(dso, machine);
826 
827 	*fd = dso__data(dso)->fd;
828 	if (*fd >= 0)
829 		return true;
830 
831 	mutex_unlock(dso__data_open_lock());
832 	return false;
833 }
834 
dso__data_put_fd(struct dso * dso __maybe_unused)835 void dso__data_put_fd(struct dso *dso __maybe_unused)
836 {
837 	mutex_unlock(dso__data_open_lock());
838 }
839 
dso__data_status_seen(struct dso * dso,enum dso_data_status_seen by)840 bool dso__data_status_seen(struct dso *dso, enum dso_data_status_seen by)
841 {
842 	u32 flag = 1 << by;
843 
844 	if (dso__data(dso)->status_seen & flag)
845 		return true;
846 
847 	dso__data(dso)->status_seen |= flag;
848 
849 	return false;
850 }
851 
852 #ifdef HAVE_LIBBPF_SUPPORT
bpf_read(struct dso * dso,u64 offset,char * data)853 static ssize_t bpf_read(struct dso *dso, u64 offset, char *data)
854 {
855 	struct bpf_prog_info_node *node;
856 	ssize_t size = DSO__DATA_CACHE_SIZE;
857 	struct dso_bpf_prog *dso_bpf_prog = dso__bpf_prog(dso);
858 	u64 len;
859 	u8 *buf;
860 
861 	node = perf_env__find_bpf_prog_info(dso_bpf_prog->env, dso_bpf_prog->id);
862 	if (!node || !node->info_linear) {
863 		dso__data(dso)->status = DSO_DATA_STATUS_ERROR;
864 		return -1;
865 	}
866 
867 	len = node->info_linear->info.jited_prog_len;
868 	buf = (u8 *)(uintptr_t)node->info_linear->info.jited_prog_insns;
869 
870 	if (offset >= len)
871 		return -1;
872 
873 	size = (ssize_t)min(len - offset, (u64)size);
874 	memcpy(data, buf + offset, size);
875 	return size;
876 }
877 
bpf_size(struct dso * dso)878 static int bpf_size(struct dso *dso)
879 {
880 	struct bpf_prog_info_node *node;
881 	struct dso_bpf_prog *dso_bpf_prog = dso__bpf_prog(dso);
882 
883 	node = perf_env__find_bpf_prog_info(dso_bpf_prog->env, dso_bpf_prog->id);
884 	if (!node || !node->info_linear) {
885 		dso__data(dso)->status = DSO_DATA_STATUS_ERROR;
886 		return -1;
887 	}
888 
889 	dso__data(dso)->file_size = node->info_linear->info.jited_prog_len;
890 	return 0;
891 }
892 #endif // HAVE_LIBBPF_SUPPORT
893 
894 static void
dso_cache__free(struct dso * dso)895 dso_cache__free(struct dso *dso)
896 {
897 	struct rb_root *root = &dso__data(dso)->cache;
898 	struct rb_node *next = rb_first(root);
899 
900 	mutex_lock(dso__lock(dso));
901 	while (next) {
902 		struct dso_cache *cache;
903 
904 		cache = rb_entry(next, struct dso_cache, rb_node);
905 		next = rb_next(&cache->rb_node);
906 		rb_erase(&cache->rb_node, root);
907 		free(cache);
908 	}
909 	mutex_unlock(dso__lock(dso));
910 }
911 
__dso_cache__find(struct dso * dso,u64 offset)912 static struct dso_cache *__dso_cache__find(struct dso *dso, u64 offset)
913 {
914 	const struct rb_root *root = &dso__data(dso)->cache;
915 	struct rb_node * const *p = &root->rb_node;
916 	const struct rb_node *parent = NULL;
917 	struct dso_cache *cache;
918 
919 	while (*p != NULL) {
920 		u64 end;
921 
922 		parent = *p;
923 		cache = rb_entry(parent, struct dso_cache, rb_node);
924 		end = cache->offset + DSO__DATA_CACHE_SIZE;
925 
926 		if (offset < cache->offset)
927 			p = &(*p)->rb_left;
928 		else if (offset >= end)
929 			p = &(*p)->rb_right;
930 		else
931 			return cache;
932 	}
933 
934 	return NULL;
935 }
936 
937 static struct dso_cache *
dso_cache__insert(struct dso * dso,struct dso_cache * new)938 dso_cache__insert(struct dso *dso, struct dso_cache *new)
939 {
940 	struct rb_root *root = &dso__data(dso)->cache;
941 	struct rb_node **p = &root->rb_node;
942 	struct rb_node *parent = NULL;
943 	struct dso_cache *cache;
944 	u64 offset = new->offset;
945 
946 	mutex_lock(dso__lock(dso));
947 	while (*p != NULL) {
948 		u64 end;
949 
950 		parent = *p;
951 		cache = rb_entry(parent, struct dso_cache, rb_node);
952 		end = cache->offset + DSO__DATA_CACHE_SIZE;
953 
954 		if (offset < cache->offset)
955 			p = &(*p)->rb_left;
956 		else if (offset >= end)
957 			p = &(*p)->rb_right;
958 		else
959 			goto out;
960 	}
961 
962 	rb_link_node(&new->rb_node, parent, p);
963 	rb_insert_color(&new->rb_node, root);
964 
965 	cache = NULL;
966 out:
967 	mutex_unlock(dso__lock(dso));
968 	return cache;
969 }
970 
dso_cache__memcpy(struct dso_cache * cache,u64 offset,u8 * data,u64 size,bool out)971 static ssize_t dso_cache__memcpy(struct dso_cache *cache, u64 offset, u8 *data,
972 				 u64 size, bool out)
973 {
974 	u64 cache_offset = offset - cache->offset;
975 	u64 cache_size   = min(cache->size - cache_offset, size);
976 
977 	if (out)
978 		memcpy(data, cache->data + cache_offset, cache_size);
979 	else
980 		memcpy(cache->data + cache_offset, data, cache_size);
981 	return cache_size;
982 }
983 
file_read(struct dso * dso,struct machine * machine,u64 offset,char * data)984 static ssize_t file_read(struct dso *dso, struct machine *machine,
985 			 u64 offset, char *data)
986 {
987 	ssize_t ret;
988 
989 	mutex_lock(dso__data_open_lock());
990 
991 	/*
992 	 * dso__data(dso)->fd might be closed if other thread opened another
993 	 * file (dso) due to open file limit (RLIMIT_NOFILE).
994 	 */
995 	try_to_open_dso(dso, machine);
996 
997 	if (dso__data(dso)->fd < 0) {
998 		dso__data(dso)->status = DSO_DATA_STATUS_ERROR;
999 		ret = -errno;
1000 		goto out;
1001 	}
1002 
1003 	ret = pread(dso__data(dso)->fd, data, DSO__DATA_CACHE_SIZE, offset);
1004 out:
1005 	mutex_unlock(dso__data_open_lock());
1006 	return ret;
1007 }
1008 
dso_cache__populate(struct dso * dso,struct machine * machine,u64 offset,ssize_t * ret)1009 static struct dso_cache *dso_cache__populate(struct dso *dso,
1010 					     struct machine *machine,
1011 					     u64 offset, ssize_t *ret)
1012 {
1013 	u64 cache_offset = offset & DSO__DATA_CACHE_MASK;
1014 	struct dso_cache *cache;
1015 	struct dso_cache *old;
1016 
1017 	cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
1018 	if (!cache) {
1019 		*ret = -ENOMEM;
1020 		return NULL;
1021 	}
1022 #ifdef HAVE_LIBBPF_SUPPORT
1023 	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_PROG_INFO)
1024 		*ret = bpf_read(dso, cache_offset, cache->data);
1025 	else
1026 #endif
1027 	if (dso__binary_type(dso) == DSO_BINARY_TYPE__OOL)
1028 		*ret = DSO__DATA_CACHE_SIZE;
1029 	else
1030 		*ret = file_read(dso, machine, cache_offset, cache->data);
1031 
1032 	if (*ret <= 0) {
1033 		free(cache);
1034 		return NULL;
1035 	}
1036 
1037 	cache->offset = cache_offset;
1038 	cache->size   = *ret;
1039 
1040 	old = dso_cache__insert(dso, cache);
1041 	if (old) {
1042 		/* we lose the race */
1043 		free(cache);
1044 		cache = old;
1045 	}
1046 
1047 	return cache;
1048 }
1049 
dso_cache__find(struct dso * dso,struct machine * machine,u64 offset,ssize_t * ret)1050 static struct dso_cache *dso_cache__find(struct dso *dso,
1051 					 struct machine *machine,
1052 					 u64 offset,
1053 					 ssize_t *ret)
1054 {
1055 	struct dso_cache *cache = __dso_cache__find(dso, offset);
1056 
1057 	return cache ? cache : dso_cache__populate(dso, machine, offset, ret);
1058 }
1059 
dso_cache_io(struct dso * dso,struct machine * machine,u64 offset,u8 * data,ssize_t size,bool out)1060 static ssize_t dso_cache_io(struct dso *dso, struct machine *machine,
1061 			    u64 offset, u8 *data, ssize_t size, bool out)
1062 {
1063 	struct dso_cache *cache;
1064 	ssize_t ret = 0;
1065 
1066 	cache = dso_cache__find(dso, machine, offset, &ret);
1067 	if (!cache)
1068 		return ret;
1069 
1070 	return dso_cache__memcpy(cache, offset, data, size, out);
1071 }
1072 
1073 /*
1074  * Reads and caches dso data DSO__DATA_CACHE_SIZE size chunks
1075  * in the rb_tree. Any read to already cached data is served
1076  * by cached data. Writes update the cache only, not the backing file.
1077  */
cached_io(struct dso * dso,struct machine * machine,u64 offset,u8 * data,ssize_t size,bool out)1078 static ssize_t cached_io(struct dso *dso, struct machine *machine,
1079 			 u64 offset, u8 *data, ssize_t size, bool out)
1080 {
1081 	ssize_t r = 0;
1082 	u8 *p = data;
1083 
1084 	do {
1085 		ssize_t ret;
1086 
1087 		ret = dso_cache_io(dso, machine, offset, p, size, out);
1088 		if (ret < 0)
1089 			return ret;
1090 
1091 		/* Reached EOF, return what we have. */
1092 		if (!ret)
1093 			break;
1094 
1095 		BUG_ON(ret > size);
1096 
1097 		r      += ret;
1098 		p      += ret;
1099 		offset += ret;
1100 		size   -= ret;
1101 
1102 	} while (size);
1103 
1104 	return r;
1105 }
1106 
file_size(struct dso * dso,struct machine * machine)1107 static int file_size(struct dso *dso, struct machine *machine)
1108 {
1109 	int ret = 0;
1110 	struct stat st;
1111 
1112 	mutex_lock(dso__data_open_lock());
1113 
1114 	/*
1115 	 * dso__data(dso)->fd might be closed if other thread opened another
1116 	 * file (dso) due to open file limit (RLIMIT_NOFILE).
1117 	 */
1118 	try_to_open_dso(dso, machine);
1119 
1120 	if (dso__data(dso)->fd < 0) {
1121 		ret = -errno;
1122 		dso__data(dso)->status = DSO_DATA_STATUS_ERROR;
1123 		goto out;
1124 	}
1125 
1126 	if (fstat(dso__data(dso)->fd, &st) < 0) {
1127 		ret = -errno;
1128 		pr_err("dso cache fstat failed: %m\n");
1129 		dso__data(dso)->status = DSO_DATA_STATUS_ERROR;
1130 		goto out;
1131 	}
1132 	dso__data(dso)->file_size = st.st_size;
1133 
1134 out:
1135 	mutex_unlock(dso__data_open_lock());
1136 	return ret;
1137 }
1138 
dso__data_file_size(struct dso * dso,struct machine * machine)1139 int dso__data_file_size(struct dso *dso, struct machine *machine)
1140 {
1141 	if (dso__data(dso)->file_size)
1142 		return 0;
1143 
1144 	if (dso__data(dso)->status == DSO_DATA_STATUS_ERROR)
1145 		return -1;
1146 #ifdef HAVE_LIBBPF_SUPPORT
1147 	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_PROG_INFO)
1148 		return bpf_size(dso);
1149 #endif
1150 	return file_size(dso, machine);
1151 }
1152 
1153 /**
1154  * dso__data_size - Return dso data size
1155  * @dso: dso object
1156  * @machine: machine object
1157  *
1158  * Return: dso data size
1159  */
dso__data_size(struct dso * dso,struct machine * machine)1160 off_t dso__data_size(struct dso *dso, struct machine *machine)
1161 {
1162 	if (dso__data_file_size(dso, machine))
1163 		return -1;
1164 
1165 	/* For now just estimate dso data size is close to file size */
1166 	return dso__data(dso)->file_size;
1167 }
1168 
data_read_write_offset(struct dso * dso,struct machine * machine,u64 offset,u8 * data,ssize_t size,bool out)1169 static ssize_t data_read_write_offset(struct dso *dso, struct machine *machine,
1170 				      u64 offset, u8 *data, ssize_t size,
1171 				      bool out)
1172 {
1173 	if (dso__data_file_size(dso, machine))
1174 		return -1;
1175 
1176 	/* Check the offset sanity. */
1177 	if (offset > dso__data(dso)->file_size)
1178 		return -1;
1179 
1180 	if (offset + size < offset)
1181 		return -1;
1182 
1183 	return cached_io(dso, machine, offset, data, size, out);
1184 }
1185 
1186 /**
1187  * dso__data_read_offset - Read data from dso file offset
1188  * @dso: dso object
1189  * @machine: machine object
1190  * @offset: file offset
1191  * @data: buffer to store data
1192  * @size: size of the @data buffer
1193  *
1194  * External interface to read data from dso file offset. Open
1195  * dso data file and use cached_read to get the data.
1196  */
dso__data_read_offset(struct dso * dso,struct machine * machine,u64 offset,u8 * data,ssize_t size)1197 ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
1198 			      u64 offset, u8 *data, ssize_t size)
1199 {
1200 	if (dso__data(dso)->status == DSO_DATA_STATUS_ERROR)
1201 		return -1;
1202 
1203 	return data_read_write_offset(dso, machine, offset, data, size, true);
1204 }
1205 
dso_swap_type__from_elf_data(unsigned char eidata)1206 static enum dso_swap_type dso_swap_type__from_elf_data(unsigned char eidata)
1207 {
1208 	static const unsigned int endian = 1;
1209 
1210 	switch (eidata) {
1211 	case ELFDATA2LSB:
1212 		/* We are big endian, DSO is little endian. */
1213 		return (*(unsigned char const *)&endian != 1) ? DSO_SWAP__YES : DSO_SWAP__NO;
1214 	case ELFDATA2MSB:
1215 		/* We are little endian, DSO is big endian. */
1216 		return (*(unsigned char const *)&endian != 0) ? DSO_SWAP__YES : DSO_SWAP__NO;
1217 	default:
1218 		return DSO_SWAP__UNSET;
1219 	}
1220 }
1221 
1222 /* Reads e_machine from fd, optionally caching data in dso. */
dso__read_e_machine(struct dso * optional_dso,int fd,uint32_t * e_flags)1223 uint16_t dso__read_e_machine(struct dso *optional_dso, int fd, uint32_t *e_flags)
1224 {
1225 	uint16_t e_machine = EM_NONE;
1226 	unsigned char e_ident[EI_NIDENT];
1227 	enum dso_swap_type swap_type;
1228 	bool need_e_flags;
1229 
1230 	if (e_flags)
1231 		*e_flags = 0;
1232 
1233 	{
1234 		_Static_assert(offsetof(Elf32_Ehdr, e_ident) == 0, "Unexpected offset");
1235 		_Static_assert(offsetof(Elf64_Ehdr, e_ident) == 0, "Unexpected offset");
1236 	}
1237 	if (pread(fd, &e_ident, sizeof(e_ident), 0) != sizeof(e_ident))
1238 		return EM_NONE; // Read failed.
1239 
1240 	if (memcmp(e_ident, ELFMAG, SELFMAG) != 0)
1241 		return EM_NONE; // Not an ELF file.
1242 
1243 	if (e_ident[EI_CLASS] == ELFCLASSNONE || e_ident[EI_CLASS] >= ELFCLASSNUM)
1244 		return EM_NONE; // Bad ELF class (32 or 64-bit objects).
1245 
1246 	if (e_ident[EI_VERSION] != EV_CURRENT)
1247 		return EM_NONE; // Bad ELF version.
1248 
1249 	swap_type = dso_swap_type__from_elf_data(e_ident[EI_DATA]);
1250 	if (swap_type == DSO_SWAP__UNSET)
1251 		return EM_NONE; // Bad ELF data encoding.
1252 
1253 	/* Cache the need for swapping. */
1254 	if (optional_dso) {
1255 		assert(dso__needs_swap(optional_dso) == DSO_SWAP__UNSET ||
1256 		       dso__needs_swap(optional_dso) == swap_type);
1257 		dso__set_needs_swap(optional_dso, swap_type);
1258 	}
1259 
1260 	{
1261 		_Static_assert(offsetof(Elf32_Ehdr, e_machine) == 18, "Unexpected offset");
1262 		_Static_assert(offsetof(Elf64_Ehdr, e_machine) == 18, "Unexpected offset");
1263 	}
1264 	if (pread(fd, &e_machine, sizeof(e_machine), 18) != sizeof(e_machine))
1265 		return EM_NONE; // e_machine read failed.
1266 
1267 	e_machine = DSO_SWAP_TYPE__SWAP(swap_type, uint16_t, e_machine);
1268 	if (e_machine >= EM_NUM)
1269 		return EM_NONE; // Bad ELF machine number.
1270 
1271 #ifdef NDEBUG
1272 	/* In production code the e_flags are only needed on CSKY. */
1273 	need_e_flags = e_flags && e_machine == EM_CSKY;
1274 #else
1275 	/* Debug code will always read the e_flags. */
1276 	need_e_flags = e_flags != NULL;
1277 #endif
1278 	if (need_e_flags) {
1279 		off_t offset = e_ident[EI_CLASS] == ELFCLASS32
1280 			? offsetof(Elf32_Ehdr, e_flags)
1281 			: offsetof(Elf64_Ehdr, e_flags);
1282 
1283 		if (pread(fd, e_flags, sizeof(*e_flags), offset) != sizeof(*e_flags)) {
1284 			*e_flags = 0;
1285 			return EM_NONE; // e_flags read failed.
1286 		}
1287 	}
1288 	return e_machine;
1289 }
1290 
dso__e_machine(struct dso * dso,struct machine * machine,uint32_t * e_flags)1291 uint16_t dso__e_machine(struct dso *dso, struct machine *machine, uint32_t *e_flags)
1292 {
1293 	uint16_t e_machine = EM_NONE;
1294 	int fd;
1295 
1296 	switch (dso__binary_type(dso)) {
1297 	case DSO_BINARY_TYPE__KALLSYMS:
1298 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1299 	case DSO_BINARY_TYPE__VMLINUX:
1300 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
1301 	case DSO_BINARY_TYPE__GUEST_KMODULE:
1302 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1303 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1304 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1305 	case DSO_BINARY_TYPE__KCORE:
1306 	case DSO_BINARY_TYPE__GUEST_KCORE:
1307 	case DSO_BINARY_TYPE__BPF_PROG_INFO:
1308 	case DSO_BINARY_TYPE__BPF_IMAGE:
1309 	case DSO_BINARY_TYPE__OOL:
1310 	case DSO_BINARY_TYPE__JAVA_JIT:
1311 		if (e_flags)
1312 			*e_flags = EF_HOST;
1313 		return EM_HOST;
1314 	case DSO_BINARY_TYPE__DEBUGLINK:
1315 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1316 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1317 	case DSO_BINARY_TYPE__GNU_DEBUGDATA:
1318 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1319 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1320 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1321 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1322 	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1323 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1324 		break;
1325 	case DSO_BINARY_TYPE__NOT_FOUND:
1326 	default:
1327 		if (e_flags)
1328 			*e_flags = 0;
1329 		return EM_NONE;
1330 	}
1331 
1332 	mutex_lock(dso__data_open_lock());
1333 
1334 	/*
1335 	 * dso__data(dso)->fd might be closed if other thread opened another
1336 	 * file (dso) due to open file limit (RLIMIT_NOFILE).
1337 	 */
1338 	try_to_open_dso(dso, machine);
1339 	fd = dso__data(dso)->fd;
1340 	if (fd >= 0)
1341 		e_machine = dso__read_e_machine(dso, fd, e_flags);
1342 	else if (e_flags)
1343 		*e_flags = 0;
1344 
1345 	mutex_unlock(dso__data_open_lock());
1346 	return e_machine;
1347 }
1348 
1349 /**
1350  * dso__data_read_addr - Read data from dso address
1351  * @dso: dso object
1352  * @machine: machine object
1353  * @add: virtual memory address
1354  * @data: buffer to store data
1355  * @size: size of the @data buffer
1356  *
1357  * External interface to read data from dso address.
1358  */
dso__data_read_addr(struct dso * dso,struct map * map,struct machine * machine,u64 addr,u8 * data,ssize_t size)1359 ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
1360 			    struct machine *machine, u64 addr,
1361 			    u8 *data, ssize_t size)
1362 {
1363 	u64 offset = map__map_ip(map, addr);
1364 
1365 	return dso__data_read_offset(dso, machine, offset, data, size);
1366 }
1367 
1368 /**
1369  * dso__data_write_cache_offs - Write data to dso data cache at file offset
1370  * @dso: dso object
1371  * @machine: machine object
1372  * @offset: file offset
1373  * @data: buffer to write
1374  * @size: size of the @data buffer
1375  *
1376  * Write into the dso file data cache, but do not change the file itself.
1377  */
dso__data_write_cache_offs(struct dso * dso,struct machine * machine,u64 offset,const u8 * data_in,ssize_t size)1378 ssize_t dso__data_write_cache_offs(struct dso *dso, struct machine *machine,
1379 				   u64 offset, const u8 *data_in, ssize_t size)
1380 {
1381 	u8 *data = (u8 *)data_in; /* cast away const to use same fns for r/w */
1382 
1383 	if (dso__data(dso)->status == DSO_DATA_STATUS_ERROR)
1384 		return -1;
1385 
1386 	return data_read_write_offset(dso, machine, offset, data, size, false);
1387 }
1388 
1389 /**
1390  * dso__data_write_cache_addr - Write data to dso data cache at dso address
1391  * @dso: dso object
1392  * @machine: machine object
1393  * @add: virtual memory address
1394  * @data: buffer to write
1395  * @size: size of the @data buffer
1396  *
1397  * External interface to write into the dso file data cache, but do not change
1398  * the file itself.
1399  */
dso__data_write_cache_addr(struct dso * dso,struct map * map,struct machine * machine,u64 addr,const u8 * data,ssize_t size)1400 ssize_t dso__data_write_cache_addr(struct dso *dso, struct map *map,
1401 				   struct machine *machine, u64 addr,
1402 				   const u8 *data, ssize_t size)
1403 {
1404 	u64 offset = map__map_ip(map, addr);
1405 
1406 	return dso__data_write_cache_offs(dso, machine, offset, data, size);
1407 }
1408 
dso__new_map(const char * name)1409 struct map *dso__new_map(const char *name)
1410 {
1411 	struct map *map = NULL;
1412 	struct dso *dso = dso__new(name);
1413 
1414 	if (dso) {
1415 		map = map__new2(0, dso);
1416 		dso__put(dso);
1417 	}
1418 
1419 	return map;
1420 }
1421 
machine__findnew_kernel(struct machine * machine,const char * name,const char * short_name,int dso_type)1422 struct dso *machine__findnew_kernel(struct machine *machine, const char *name,
1423 				    const char *short_name, int dso_type)
1424 {
1425 	/*
1426 	 * The kernel dso could be created by build_id processing.
1427 	 */
1428 	struct dso *dso = machine__findnew_dso(machine, name);
1429 
1430 	/*
1431 	 * We need to run this in all cases, since during the build_id
1432 	 * processing we had no idea this was the kernel dso.
1433 	 */
1434 	if (dso != NULL) {
1435 		dso__set_short_name(dso, short_name, false);
1436 		dso__set_kernel(dso, dso_type);
1437 	}
1438 
1439 	return dso;
1440 }
1441 
__dso__set_long_name_id(struct dso * dso,const char * name,bool name_allocated)1442 static void __dso__set_long_name_id(struct dso *dso, const char *name, bool name_allocated)
1443 {
1444 	if (dso__long_name_allocated(dso))
1445 		free((char *)dso__long_name(dso));
1446 
1447 	RC_CHK_ACCESS(dso)->long_name = name;
1448 	RC_CHK_ACCESS(dso)->long_name_len = strlen(name);
1449 	dso__set_long_name_allocated(dso, name_allocated);
1450 }
1451 
dso__set_long_name_id(struct dso * dso,const char * name,bool name_allocated)1452 static void dso__set_long_name_id(struct dso *dso, const char *name, bool name_allocated)
1453 {
1454 	struct dsos *dsos = dso__dsos(dso);
1455 
1456 	if (name == NULL)
1457 		return;
1458 
1459 	if (dsos) {
1460 		/*
1461 		 * Need to avoid re-sorting the dsos breaking by non-atomically
1462 		 * renaming the dso.
1463 		 */
1464 		down_write(&dsos->lock);
1465 		__dso__set_long_name_id(dso, name, name_allocated);
1466 		dsos->sorted = false;
1467 		up_write(&dsos->lock);
1468 	} else {
1469 		__dso__set_long_name_id(dso, name, name_allocated);
1470 	}
1471 }
1472 
__dso_id__cmp(const struct dso_id * a,const struct dso_id * b)1473 static int __dso_id__cmp(const struct dso_id *a, const struct dso_id *b)
1474 {
1475 	if (a->mmap2_valid && b->mmap2_valid) {
1476 		if (a->maj > b->maj) return -1;
1477 		if (a->maj < b->maj) return 1;
1478 
1479 		if (a->min > b->min) return -1;
1480 		if (a->min < b->min) return 1;
1481 
1482 		if (a->ino > b->ino) return -1;
1483 		if (a->ino < b->ino) return 1;
1484 	}
1485 	if (a->mmap2_ino_generation_valid && b->mmap2_ino_generation_valid) {
1486 		if (a->ino_generation > b->ino_generation) return -1;
1487 		if (a->ino_generation < b->ino_generation) return 1;
1488 	}
1489 	if (build_id__is_defined(&a->build_id) && build_id__is_defined(&b->build_id)) {
1490 		if (a->build_id.size != b->build_id.size)
1491 			return a->build_id.size < b->build_id.size ? -1 : 1;
1492 		return memcmp(a->build_id.data, b->build_id.data, a->build_id.size);
1493 	}
1494 	return 0;
1495 }
1496 
1497 const struct dso_id dso_id_empty = {
1498 	{
1499 		.maj = 0,
1500 		.min = 0,
1501 		.ino = 0,
1502 		.ino_generation = 0,
1503 	},
1504 	.mmap2_valid = false,
1505 	.mmap2_ino_generation_valid = false,
1506 	{
1507 		.size = 0,
1508 	}
1509 };
1510 
__dso__improve_id(struct dso * dso,const struct dso_id * id)1511 void __dso__improve_id(struct dso *dso, const struct dso_id *id)
1512 {
1513 	struct dsos *dsos = dso__dsos(dso);
1514 	struct dso_id *dso_id = dso__id(dso);
1515 	bool changed = false;
1516 
1517 	/* dsos write lock held by caller. */
1518 
1519 	if (id->mmap2_valid && !dso_id->mmap2_valid) {
1520 		dso_id->maj = id->maj;
1521 		dso_id->min = id->min;
1522 		dso_id->ino = id->ino;
1523 		dso_id->mmap2_valid = true;
1524 		changed = true;
1525 	}
1526 	if (id->mmap2_ino_generation_valid && !dso_id->mmap2_ino_generation_valid) {
1527 		dso_id->ino_generation = id->ino_generation;
1528 		dso_id->mmap2_ino_generation_valid = true;
1529 		changed = true;
1530 	}
1531 	if (build_id__is_defined(&id->build_id) && !build_id__is_defined(&dso_id->build_id)) {
1532 		dso_id->build_id = id->build_id;
1533 		changed = true;
1534 	}
1535 	if (changed && dsos)
1536 		dsos->sorted = false;
1537 }
1538 
dso_id__cmp(const struct dso_id * a,const struct dso_id * b)1539 int dso_id__cmp(const struct dso_id *a, const struct dso_id *b)
1540 {
1541 	if (a == &dso_id_empty || b == &dso_id_empty) {
1542 		/* There is no valid data to compare so the comparison always returns identical. */
1543 		return 0;
1544 	}
1545 
1546 	return __dso_id__cmp(a, b);
1547 }
1548 
dso__cmp_id(struct dso * a,struct dso * b)1549 int dso__cmp_id(struct dso *a, struct dso *b)
1550 {
1551 	return __dso_id__cmp(dso__id(a), dso__id(b));
1552 }
1553 
dso__set_long_name(struct dso * dso,const char * name,bool name_allocated)1554 void dso__set_long_name(struct dso *dso, const char *name, bool name_allocated)
1555 {
1556 	dso__set_long_name_id(dso, name, name_allocated);
1557 }
1558 
__dso__set_short_name(struct dso * dso,const char * name,bool name_allocated)1559 static void __dso__set_short_name(struct dso *dso, const char *name, bool name_allocated)
1560 {
1561 	if (dso__short_name_allocated(dso))
1562 		free((char *)dso__short_name(dso));
1563 
1564 	RC_CHK_ACCESS(dso)->short_name		  = name;
1565 	RC_CHK_ACCESS(dso)->short_name_len	  = strlen(name);
1566 	dso__set_short_name_allocated(dso, name_allocated);
1567 }
1568 
dso__set_short_name(struct dso * dso,const char * name,bool name_allocated)1569 void dso__set_short_name(struct dso *dso, const char *name, bool name_allocated)
1570 {
1571 	struct dsos *dsos = dso__dsos(dso);
1572 
1573 	if (name == NULL)
1574 		return;
1575 
1576 	if (dsos) {
1577 		/*
1578 		 * Need to avoid re-sorting the dsos breaking by non-atomically
1579 		 * renaming the dso.
1580 		 */
1581 		down_write(&dsos->lock);
1582 		__dso__set_short_name(dso, name, name_allocated);
1583 		dsos->sorted = false;
1584 		up_write(&dsos->lock);
1585 	} else {
1586 		__dso__set_short_name(dso, name, name_allocated);
1587 	}
1588 }
1589 
dso__name_len(const struct dso * dso)1590 int dso__name_len(const struct dso *dso)
1591 {
1592 	if (!dso)
1593 		return strlen("[unknown]");
1594 	if (verbose > 0)
1595 		return dso__long_name_len(dso);
1596 
1597 	return dso__short_name_len(dso);
1598 }
1599 
dso__loaded(const struct dso * dso)1600 bool dso__loaded(const struct dso *dso)
1601 {
1602 	return RC_CHK_ACCESS(dso)->loaded;
1603 }
1604 
dso__sorted_by_name(const struct dso * dso)1605 bool dso__sorted_by_name(const struct dso *dso)
1606 {
1607 	return RC_CHK_ACCESS(dso)->sorted_by_name;
1608 }
1609 
dso__set_sorted_by_name(struct dso * dso)1610 void dso__set_sorted_by_name(struct dso *dso)
1611 {
1612 	RC_CHK_ACCESS(dso)->sorted_by_name = true;
1613 }
1614 
dso__new_id(const char * name,const struct dso_id * id)1615 struct dso *dso__new_id(const char *name, const struct dso_id *id)
1616 {
1617 	RC_STRUCT(dso) *dso = zalloc(sizeof(*dso) + strlen(name) + 1);
1618 	struct dso *res;
1619 	struct dso_data *data;
1620 
1621 	if (!dso)
1622 		return NULL;
1623 
1624 	if (ADD_RC_CHK(res, dso)) {
1625 		strcpy(dso->name, name);
1626 		if (id)
1627 			dso->id = *id;
1628 		dso__set_long_name_id(res, dso->name, false);
1629 		dso__set_short_name(res, dso->name, false);
1630 		dso->symbols = RB_ROOT_CACHED;
1631 		dso->symbol_names = NULL;
1632 		dso->symbol_names_len = 0;
1633 		dso->inlined_nodes = RB_ROOT_CACHED;
1634 		dso->srclines = RB_ROOT_CACHED;
1635 		dso->data_types = RB_ROOT;
1636 		dso->global_vars = RB_ROOT;
1637 		dso->data.fd = -1;
1638 		dso->data.status = DSO_DATA_STATUS_UNKNOWN;
1639 		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
1640 		dso->binary_type = DSO_BINARY_TYPE__NOT_FOUND;
1641 		dso->is_64_bit = (sizeof(void *) == 8);
1642 		dso->loaded = 0;
1643 		dso->rel = 0;
1644 		dso->sorted_by_name = 0;
1645 		dso->has_srcline = 1;
1646 		dso->a2l_fails = 1;
1647 		dso->kernel = DSO_SPACE__USER;
1648 		dso->is_kmod = 0;
1649 		dso->needs_swap = DSO_SWAP__UNSET;
1650 		dso->comp = COMP_ID__NONE;
1651 		mutex_init(&dso->lock);
1652 		refcount_set(&dso->refcnt, 1);
1653 		data = &dso->data;
1654 		data->cache = RB_ROOT;
1655 		data->fd = -1;
1656 		data->status = DSO_DATA_STATUS_UNKNOWN;
1657 		INIT_LIST_HEAD(&data->open_entry);
1658 #ifdef REFCNT_CHECKING
1659 		data->dso = NULL; /* Set when on the open_entry list. */
1660 #endif
1661 	}
1662 	return res;
1663 }
1664 
dso__new(const char * name)1665 struct dso *dso__new(const char *name)
1666 {
1667 	return dso__new_id(name, NULL);
1668 }
1669 
dso__delete(struct dso * dso)1670 void dso__delete(struct dso *dso)
1671 {
1672 	if (dso__dsos(dso))
1673 		pr_err("DSO %s is still in rbtree when being deleted!\n", dso__long_name(dso));
1674 
1675 	/* free inlines first, as they reference symbols */
1676 	inlines__tree_delete(&RC_CHK_ACCESS(dso)->inlined_nodes);
1677 	srcline__tree_delete(&RC_CHK_ACCESS(dso)->srclines);
1678 	symbols__delete(&RC_CHK_ACCESS(dso)->symbols);
1679 	RC_CHK_ACCESS(dso)->symbol_names_len = 0;
1680 	zfree(&RC_CHK_ACCESS(dso)->symbol_names);
1681 	annotated_data_type__tree_delete(dso__data_types(dso));
1682 	global_var_type__tree_delete(dso__global_vars(dso));
1683 
1684 	if (RC_CHK_ACCESS(dso)->short_name_allocated) {
1685 		zfree((char **)&RC_CHK_ACCESS(dso)->short_name);
1686 		RC_CHK_ACCESS(dso)->short_name_allocated = false;
1687 	}
1688 
1689 	if (RC_CHK_ACCESS(dso)->long_name_allocated) {
1690 		zfree((char **)&RC_CHK_ACCESS(dso)->long_name);
1691 		RC_CHK_ACCESS(dso)->long_name_allocated = false;
1692 	}
1693 
1694 	dso__data_close(dso);
1695 	auxtrace_cache__free(RC_CHK_ACCESS(dso)->auxtrace_cache);
1696 	dso_cache__free(dso);
1697 	dso__free_a2l(dso);
1698 	dso__free_libdw(dso);
1699 	dso__free_symsrc_filename(dso);
1700 	nsinfo__zput(RC_CHK_ACCESS(dso)->nsinfo);
1701 	mutex_destroy(dso__lock(dso));
1702 	RC_CHK_FREE(dso);
1703 }
1704 
dso__get(struct dso * dso)1705 struct dso *dso__get(struct dso *dso)
1706 {
1707 	struct dso *result;
1708 
1709 	if (RC_CHK_GET(result, dso))
1710 		refcount_inc(&RC_CHK_ACCESS(dso)->refcnt);
1711 
1712 	return result;
1713 }
1714 
dso__put(struct dso * dso)1715 void dso__put(struct dso *dso)
1716 {
1717 #ifdef REFCNT_CHECKING
1718 	if (dso && dso__data(dso) && refcount_read(&RC_CHK_ACCESS(dso)->refcnt) == 2)
1719 		dso__data_close(dso);
1720 #endif
1721 	if (dso && refcount_dec_and_test(&RC_CHK_ACCESS(dso)->refcnt))
1722 		dso__delete(dso);
1723 	else
1724 		RC_CHK_PUT(dso);
1725 }
1726 
dso__swap_init(struct dso * dso,unsigned char eidata)1727 int dso__swap_init(struct dso *dso, unsigned char eidata)
1728 {
1729 	enum dso_swap_type type = dso_swap_type__from_elf_data(eidata);
1730 
1731 	dso__set_needs_swap(dso, type);
1732 	if (type == DSO_SWAP__UNSET) {
1733 		pr_err("unrecognized DSO data encoding %d\n", eidata);
1734 		return -EINVAL;
1735 	}
1736 	return 0;
1737 }
1738 
dso__set_build_id(struct dso * dso,const struct build_id * bid)1739 void dso__set_build_id(struct dso *dso, const struct build_id *bid)
1740 {
1741 	dso__id(dso)->build_id = *bid;
1742 }
1743 
dso__build_id_equal(const struct dso * dso,const struct build_id * bid)1744 bool dso__build_id_equal(const struct dso *dso, const struct build_id *bid)
1745 {
1746 	const struct build_id *dso_bid = dso__bid(dso);
1747 
1748 	if (dso_bid->size > bid->size && dso_bid->size == BUILD_ID_SIZE) {
1749 		/*
1750 		 * For the backward compatibility, it allows a build-id has
1751 		 * trailing zeros.
1752 		 */
1753 		return !memcmp(dso_bid->data, bid->data, bid->size) &&
1754 			!memchr_inv(&dso_bid->data[bid->size], 0,
1755 				    dso_bid->size - bid->size);
1756 	}
1757 
1758 	return dso_bid->size == bid->size &&
1759 	       memcmp(dso_bid->data, bid->data, dso_bid->size) == 0;
1760 }
1761 
dso__read_running_kernel_build_id(struct dso * dso,struct machine * machine)1762 void dso__read_running_kernel_build_id(struct dso *dso, struct machine *machine)
1763 {
1764 	char path[PATH_MAX];
1765 	struct build_id bid = { .size = 0, };
1766 
1767 	if (machine__is_default_guest(machine))
1768 		return;
1769 	sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
1770 	sysfs__read_build_id(path, &bid);
1771 	dso__set_build_id(dso, &bid);
1772 }
1773 
dso__kernel_module_get_build_id(struct dso * dso,const char * root_dir)1774 int dso__kernel_module_get_build_id(struct dso *dso,
1775 				    const char *root_dir)
1776 {
1777 	char filename[PATH_MAX];
1778 	struct build_id bid = { .size = 0, };
1779 	/*
1780 	 * kernel module short names are of the form "[module]" and
1781 	 * we need just "module" here.
1782 	 */
1783 	const char *name = dso__short_name(dso) + 1;
1784 
1785 	snprintf(filename, sizeof(filename),
1786 		 "%s/sys/module/%.*s/notes/.note.gnu.build-id",
1787 		 root_dir, (int)strlen(name) - 1, name);
1788 
1789 	sysfs__read_build_id(filename, &bid);
1790 	dso__set_build_id(dso, &bid);
1791 	return 0;
1792 }
1793 
dso__fprintf_buildid(struct dso * dso,FILE * fp)1794 static size_t dso__fprintf_buildid(struct dso *dso, FILE *fp)
1795 {
1796 	char sbuild_id[SBUILD_ID_SIZE];
1797 
1798 	build_id__snprintf(dso__bid(dso), sbuild_id, sizeof(sbuild_id));
1799 	return fprintf(fp, "%s", sbuild_id);
1800 }
1801 
dso__fprintf(struct dso * dso,FILE * fp)1802 size_t dso__fprintf(struct dso *dso, FILE *fp)
1803 {
1804 	struct rb_node *nd;
1805 	size_t ret = fprintf(fp, "dso: %s (", dso__short_name(dso));
1806 
1807 	if (dso__short_name(dso) != dso__long_name(dso))
1808 		ret += fprintf(fp, "%s, ", dso__long_name(dso));
1809 	ret += fprintf(fp, "%sloaded, ", dso__loaded(dso) ? "" : "NOT ");
1810 	ret += dso__fprintf_buildid(dso, fp);
1811 	ret += fprintf(fp, ")\n");
1812 	for (nd = rb_first_cached(dso__symbols(dso)); nd; nd = rb_next(nd)) {
1813 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
1814 		ret += symbol__fprintf(pos, fp);
1815 	}
1816 
1817 	return ret;
1818 }
1819 
dso__type(struct dso * dso,struct machine * machine)1820 enum dso_type dso__type(struct dso *dso, struct machine *machine)
1821 {
1822 	int fd = -1;
1823 	enum dso_type type = DSO__TYPE_UNKNOWN;
1824 
1825 	if (dso__data_get_fd(dso, machine, &fd)) {
1826 		type = dso__type_fd(fd);
1827 		dso__data_put_fd(dso);
1828 	}
1829 
1830 	return type;
1831 }
1832 
dso__strerror_load(struct dso * dso,char * buf,size_t buflen)1833 int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
1834 {
1835 	int idx, errnum = *dso__load_errno(dso);
1836 	/*
1837 	 * This must have a same ordering as the enum dso_load_errno.
1838 	 */
1839 	static const char *dso_load__error_str[] = {
1840 	"Internal tools/perf/ library error",
1841 	"Invalid ELF file",
1842 	"Can not read build id",
1843 	"Mismatching build id",
1844 	"Decompression failure",
1845 	};
1846 
1847 	BUG_ON(buflen == 0);
1848 
1849 	if (errnum >= 0) {
1850 		errno = errnum;
1851 		scnprintf(buf, buflen, "%m");
1852 
1853 		return 0;
1854 	}
1855 
1856 	if (errnum <  __DSO_LOAD_ERRNO__START || errnum >= __DSO_LOAD_ERRNO__END)
1857 		return -1;
1858 
1859 	idx = errnum - __DSO_LOAD_ERRNO__START;
1860 	scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
1861 	return 0;
1862 }
1863 
perf_pid_map_tid(const char * dso_name,int * tid)1864 bool perf_pid_map_tid(const char *dso_name, int *tid)
1865 {
1866 	return sscanf(dso_name, "/tmp/perf-%d.map", tid) == 1;
1867 }
1868 
is_perf_pid_map_name(const char * dso_name)1869 bool is_perf_pid_map_name(const char *dso_name)
1870 {
1871 	int tid;
1872 
1873 	return perf_pid_map_tid(dso_name, &tid);
1874 }
1875 
1876 struct find_file_offset_data {
1877 	u64 ip;
1878 	u64 offset;
1879 };
1880 
1881 /* This will be called for each PHDR in an ELF binary */
find_file_offset(u64 start,u64 len,u64 pgoff,void * arg)1882 static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg)
1883 {
1884 	struct find_file_offset_data *data = arg;
1885 
1886 	if (start <= data->ip && data->ip < start + len) {
1887 		data->offset = pgoff + data->ip - start;
1888 		return 1;
1889 	}
1890 	return 0;
1891 }
1892 
__dso__read_symbol(struct dso * dso,const char * symfs_filename,u64 start,size_t len,u8 ** out_buf,u64 * out_buf_len,bool * is_64bit)1893 static const u8 *__dso__read_symbol(struct dso *dso, const char *symfs_filename,
1894 				    u64 start, size_t len,
1895 				    u8 **out_buf, u64 *out_buf_len, bool *is_64bit)
1896 {
1897 	struct nscookie nsc;
1898 	int fd;
1899 	ssize_t count;
1900 	struct find_file_offset_data data = {
1901 		.ip = start,
1902 	};
1903 	u8 *code_buf = NULL;
1904 	int saved_errno;
1905 
1906 	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
1907 	fd = open(symfs_filename, O_RDONLY);
1908 	saved_errno = errno;
1909 	nsinfo__mountns_exit(&nsc);
1910 	if (fd < 0) {
1911 		errno = saved_errno;
1912 		return NULL;
1913 	}
1914 	if (file__read_maps(fd, /*exe=*/true, find_file_offset, &data, is_64bit) <= 0) {
1915 		close(fd);
1916 		errno = ENOENT;
1917 		return NULL;
1918 	}
1919 	code_buf = malloc(len);
1920 	if (code_buf == NULL) {
1921 		close(fd);
1922 		errno = ENOMEM;
1923 		return NULL;
1924 	}
1925 	count = pread(fd, code_buf, len, data.offset);
1926 	saved_errno = errno;
1927 	close(fd);
1928 	if ((u64)count != len) {
1929 		free(code_buf);
1930 		errno = saved_errno;
1931 		return NULL;
1932 	}
1933 	*out_buf = code_buf;
1934 	*out_buf_len = len;
1935 	return code_buf;
1936 }
1937 
1938 /*
1939  * Read a symbol into memory for disassembly by a library like capstone of
1940  * libLLVM. If memory is allocated out_buf holds it.
1941  */
dso__read_symbol(struct dso * dso,const char * symfs_filename,const struct map * map,const struct symbol * sym,u8 ** out_buf,u64 * out_buf_len,bool * is_64bit)1942 const u8 *dso__read_symbol(struct dso *dso, const char *symfs_filename,
1943 			   const struct map *map, const struct symbol *sym,
1944 			   u8 **out_buf, u64 *out_buf_len, bool *is_64bit)
1945 {
1946 	u64 start = map__rip_2objdump(map, sym->start);
1947 	u64 end = map__rip_2objdump(map, sym->end);
1948 	size_t len = end - start;
1949 
1950 	*out_buf = NULL;
1951 	*out_buf_len = 0;
1952 	*is_64bit = false;
1953 
1954 	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_IMAGE) {
1955 		/*
1956 		 * Note, there is fallback BPF image disassembly in the objdump
1957 		 * version but it currently does nothing.
1958 		 */
1959 		errno = EOPNOTSUPP;
1960 		return NULL;
1961 	}
1962 	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_PROG_INFO) {
1963 #ifdef HAVE_LIBBPF_SUPPORT
1964 		struct bpf_prog_info_node *info_node;
1965 		struct perf_bpil *info_linear;
1966 
1967 		*is_64bit = sizeof(void *) == sizeof(u64);
1968 		info_node = perf_env__find_bpf_prog_info(dso__bpf_prog(dso)->env,
1969 							 dso__bpf_prog(dso)->id);
1970 		if (!info_node) {
1971 			errno = SYMBOL_ANNOTATE_ERRNO__BPF_MISSING_BTF;
1972 			return NULL;
1973 		}
1974 		info_linear = info_node->info_linear;
1975 		assert(len <= info_linear->info.jited_prog_len);
1976 		*out_buf_len = len;
1977 		return (const u8 *)(uintptr_t)(info_linear->info.jited_prog_insns);
1978 #else
1979 		pr_debug("No BPF program disassembly support\n");
1980 		errno = EOPNOTSUPP;
1981 		return NULL;
1982 #endif
1983 	}
1984 	return __dso__read_symbol(dso, symfs_filename, start, len,
1985 				  out_buf, out_buf_len, is_64bit);
1986 }
1987 
dso__debuginfo(struct dso * dso)1988 struct debuginfo *dso__debuginfo(struct dso *dso)
1989 {
1990 	char *name;
1991 	bool decomp = false;
1992 	struct debuginfo *dinfo = NULL;
1993 
1994 	mutex_lock(dso__lock(dso));
1995 
1996 	name = dso__get_filename(dso, "", &decomp);
1997 	if (name)
1998 		dinfo = debuginfo__new(name);
1999 
2000 	if (decomp)
2001 		unlink(name);
2002 
2003 	mutex_unlock(dso__lock(dso));
2004 	free(name);
2005 	return dinfo;
2006 }
2007