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1// SPDX-License-Identifier: GPL-2.0
2#include <linux/compiler.h>
3#include <linux/kernel.h>
4#include <linux/string.h>
5#include <linux/zalloc.h>
6#include <linux/err.h>
7#include <sys/types.h>
8#include <sys/stat.h>
9#include <errno.h>
10#include <fcntl.h>
11#include <unistd.h>
12#include <string.h>
13#include <asm/bug.h>
14#include <dirent.h>
15
16#include "data.h"
17#include "util.h" // rm_rf_perf_data()
18#include "debug.h"
19#include "header.h"
20#include <internal/lib.h>
21
22static void close_dir(struct perf_data_file *files, int nr)
23{
24 while (--nr >= 0) {
25 close(files[nr].fd);
26 zfree(&files[nr].path);
27 }
28 free(files);
29}
30
31void perf_data__close_dir(struct perf_data *data)
32{
33 close_dir(data->dir.files, data->dir.nr);
34}
35
36int perf_data__create_dir(struct perf_data *data, int nr)
37{
38 struct perf_data_file *files = NULL;
39 int i, ret;
40
41 if (WARN_ON(!data->is_dir))
42 return -EINVAL;
43
44 files = zalloc(nr * sizeof(*files));
45 if (!files)
46 return -ENOMEM;
47
48 for (i = 0; i < nr; i++) {
49 struct perf_data_file *file = &files[i];
50
51 ret = asprintf(&file->path, "%s/data.%d", data->path, i);
52 if (ret < 0) {
53 ret = -ENOMEM;
54 goto out_err;
55 }
56
57 ret = open(file->path, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);
58 if (ret < 0) {
59 ret = -errno;
60 goto out_err;
61 }
62
63 file->fd = ret;
64 }
65
66 data->dir.version = PERF_DIR_VERSION;
67 data->dir.files = files;
68 data->dir.nr = nr;
69 return 0;
70
71out_err:
72 close_dir(files, i);
73 return ret;
74}
75
76int perf_data__open_dir(struct perf_data *data)
77{
78 struct perf_data_file *files = NULL;
79 struct dirent *dent;
80 int ret = -1;
81 DIR *dir;
82 int nr = 0;
83
84 /*
85 * Directory containing a single regular perf data file which is already
86 * open, means there is nothing more to do here.
87 */
88 if (perf_data__is_single_file(data))
89 return 0;
90
91 if (WARN_ON(!data->is_dir))
92 return -EINVAL;
93
94 /* The version is provided by DIR_FORMAT feature. */
95 if (WARN_ON(data->dir.version != PERF_DIR_VERSION))
96 return -1;
97
98 dir = opendir(data->path);
99 if (!dir)
100 return -EINVAL;
101
102 while ((dent = readdir(dir)) != NULL) {
103 struct perf_data_file *file;
104 char path[PATH_MAX];
105 struct stat st;
106
107 snprintf(path, sizeof(path), "%s/%s", data->path, dent->d_name);
108 if (stat(path, &st))
109 continue;
110
111 if (!S_ISREG(st.st_mode) || strncmp(dent->d_name, "data.", 5))
112 continue;
113
114 ret = -ENOMEM;
115
116 file = realloc(files, (nr + 1) * sizeof(*files));
117 if (!file)
118 goto out_err;
119
120 files = file;
121 file = &files[nr++];
122
123 file->path = strdup(path);
124 if (!file->path)
125 goto out_err;
126
127 ret = open(file->path, O_RDONLY);
128 if (ret < 0)
129 goto out_err;
130
131 file->fd = ret;
132 file->size = st.st_size;
133 }
134
135 closedir(dir);
136 if (!files)
137 return -EINVAL;
138
139 data->dir.files = files;
140 data->dir.nr = nr;
141 return 0;
142
143out_err:
144 closedir(dir);
145 close_dir(files, nr);
146 return ret;
147}
148
149int perf_data__update_dir(struct perf_data *data)
150{
151 int i;
152
153 if (WARN_ON(!data->is_dir))
154 return -EINVAL;
155
156 for (i = 0; i < data->dir.nr; i++) {
157 struct perf_data_file *file = &data->dir.files[i];
158 struct stat st;
159
160 if (fstat(file->fd, &st))
161 return -1;
162
163 file->size = st.st_size;
164 }
165
166 return 0;
167}
168
169static bool check_pipe(struct perf_data *data)
170{
171 struct stat st;
172 bool is_pipe = false;
173 int fd = perf_data__is_read(data) ?
174 STDIN_FILENO : STDOUT_FILENO;
175
176 if (!data->path) {
177 if (!fstat(fd, &st) && S_ISFIFO(st.st_mode))
178 is_pipe = true;
179 } else {
180 if (!strcmp(data->path, "-"))
181 is_pipe = true;
182 }
183
184 if (is_pipe) {
185 if (data->use_stdio) {
186 const char *mode;
187
188 mode = perf_data__is_read(data) ? "r" : "w";
189 data->file.fptr = fdopen(fd, mode);
190
191 if (data->file.fptr == NULL) {
192 data->file.fd = fd;
193 data->use_stdio = false;
194 }
195 } else {
196 data->file.fd = fd;
197 }
198 }
199
200 return data->is_pipe = is_pipe;
201}
202
203static int check_backup(struct perf_data *data)
204{
205 struct stat st;
206
207 if (perf_data__is_read(data))
208 return 0;
209
210 if (!stat(data->path, &st) && st.st_size) {
211 char oldname[PATH_MAX];
212 int ret;
213
214 snprintf(oldname, sizeof(oldname), "%s.old",
215 data->path);
216
217 ret = rm_rf_perf_data(oldname);
218 if (ret) {
219 pr_err("Can't remove old data: %s (%s)\n",
220 ret == -2 ?
221 "Unknown file found" : strerror(errno),
222 oldname);
223 return -1;
224 }
225
226 if (rename(data->path, oldname)) {
227 pr_err("Can't move data: %s (%s to %s)\n",
228 strerror(errno),
229 data->path, oldname);
230 return -1;
231 }
232 }
233
234 return 0;
235}
236
237static bool is_dir(struct perf_data *data)
238{
239 struct stat st;
240
241 if (stat(data->path, &st))
242 return false;
243
244 return (st.st_mode & S_IFMT) == S_IFDIR;
245}
246
247static int open_file_read(struct perf_data *data)
248{
249 int flags = data->in_place_update ? O_RDWR : O_RDONLY;
250 struct stat st;
251 int fd;
252 char sbuf[STRERR_BUFSIZE];
253
254 fd = open(data->file.path, flags);
255 if (fd < 0) {
256 int err = errno;
257
258 pr_err("failed to open %s: %s", data->file.path,
259 str_error_r(err, sbuf, sizeof(sbuf)));
260 if (err == ENOENT && !strcmp(data->file.path, "perf.data"))
261 pr_err(" (try 'perf record' first)");
262 pr_err("\n");
263 return -err;
264 }
265
266 if (fstat(fd, &st) < 0)
267 goto out_close;
268
269 if (!data->force && st.st_uid && (st.st_uid != geteuid())) {
270 pr_err("File %s not owned by current user or root (use -f to override)\n",
271 data->file.path);
272 goto out_close;
273 }
274
275 if (!st.st_size) {
276 pr_info("zero-sized data (%s), nothing to do!\n",
277 data->file.path);
278 goto out_close;
279 }
280
281 data->file.size = st.st_size;
282 return fd;
283
284 out_close:
285 close(fd);
286 return -1;
287}
288
289static int open_file_write(struct perf_data *data)
290{
291 int fd;
292 char sbuf[STRERR_BUFSIZE];
293
294 fd = open(data->file.path, O_CREAT|O_RDWR|O_TRUNC|O_CLOEXEC,
295 S_IRUSR|S_IWUSR);
296
297 if (fd < 0)
298 pr_err("failed to open %s : %s\n", data->file.path,
299 str_error_r(errno, sbuf, sizeof(sbuf)));
300
301 return fd;
302}
303
304static int open_file(struct perf_data *data)
305{
306 int fd;
307
308 fd = perf_data__is_read(data) ?
309 open_file_read(data) : open_file_write(data);
310
311 if (fd < 0) {
312 zfree(&data->file.path);
313 return -1;
314 }
315
316 data->file.fd = fd;
317 return 0;
318}
319
320static int open_file_dup(struct perf_data *data)
321{
322 data->file.path = strdup(data->path);
323 if (!data->file.path)
324 return -ENOMEM;
325
326 return open_file(data);
327}
328
329static int open_dir(struct perf_data *data)
330{
331 int ret;
332
333 /*
334 * So far we open only the header, so we can read the data version and
335 * layout.
336 */
337 if (asprintf(&data->file.path, "%s/data", data->path) < 0)
338 return -1;
339
340 if (perf_data__is_write(data) &&
341 mkdir(data->path, S_IRWXU) < 0)
342 return -1;
343
344 ret = open_file(data);
345
346 /* Cleanup whatever we managed to create so far. */
347 if (ret && perf_data__is_write(data))
348 rm_rf_perf_data(data->path);
349
350 return ret;
351}
352
353int perf_data__open(struct perf_data *data)
354{
355 if (check_pipe(data))
356 return 0;
357
358 /* currently it allows stdio for pipe only */
359 data->use_stdio = false;
360
361 if (!data->path)
362 data->path = "perf.data";
363
364 if (check_backup(data))
365 return -1;
366
367 if (perf_data__is_read(data))
368 data->is_dir = is_dir(data);
369
370 return perf_data__is_dir(data) ?
371 open_dir(data) : open_file_dup(data);
372}
373
374void perf_data__close(struct perf_data *data)
375{
376 if (perf_data__is_dir(data))
377 perf_data__close_dir(data);
378
379 zfree(&data->file.path);
380
381 if (data->use_stdio)
382 fclose(data->file.fptr);
383 else
384 close(data->file.fd);
385}
386
387ssize_t perf_data__read(struct perf_data *data, void *buf, size_t size)
388{
389 if (data->use_stdio) {
390 if (fread(buf, size, 1, data->file.fptr) == 1)
391 return size;
392 return feof(data->file.fptr) ? 0 : -1;
393 }
394 return readn(data->file.fd, buf, size);
395}
396
397ssize_t perf_data_file__write(struct perf_data_file *file,
398 void *buf, size_t size)
399{
400 return writen(file->fd, buf, size);
401}
402
403ssize_t perf_data__write(struct perf_data *data,
404 void *buf, size_t size)
405{
406 if (data->use_stdio) {
407 if (fwrite(buf, size, 1, data->file.fptr) == 1)
408 return size;
409 return -1;
410 }
411 return perf_data_file__write(&data->file, buf, size);
412}
413
414int perf_data__switch(struct perf_data *data,
415 const char *postfix,
416 size_t pos, bool at_exit,
417 char **new_filepath)
418{
419 int ret;
420
421 if (check_pipe(data))
422 return -EINVAL;
423 if (perf_data__is_read(data))
424 return -EINVAL;
425
426 if (asprintf(new_filepath, "%s.%s", data->path, postfix) < 0)
427 return -ENOMEM;
428
429 /*
430 * Only fire a warning, don't return error, continue fill
431 * original file.
432 */
433 if (rename(data->path, *new_filepath))
434 pr_warning("Failed to rename %s to %s\n", data->path, *new_filepath);
435
436 if (!at_exit) {
437 close(data->file.fd);
438 ret = perf_data__open(data);
439 if (ret < 0)
440 goto out;
441
442 if (lseek(data->file.fd, pos, SEEK_SET) == (off_t)-1) {
443 ret = -errno;
444 pr_debug("Failed to lseek to %zu: %s",
445 pos, strerror(errno));
446 goto out;
447 }
448 }
449 ret = data->file.fd;
450out:
451 return ret;
452}
453
454unsigned long perf_data__size(struct perf_data *data)
455{
456 u64 size = data->file.size;
457 int i;
458
459 if (perf_data__is_single_file(data))
460 return size;
461
462 for (i = 0; i < data->dir.nr; i++) {
463 struct perf_data_file *file = &data->dir.files[i];
464
465 size += file->size;
466 }
467
468 return size;
469}
470
471int perf_data__make_kcore_dir(struct perf_data *data, char *buf, size_t buf_sz)
472{
473 int ret;
474
475 if (!data->is_dir)
476 return -1;
477
478 ret = snprintf(buf, buf_sz, "%s/kcore_dir", data->path);
479 if (ret < 0 || (size_t)ret >= buf_sz)
480 return -1;
481
482 return mkdir(buf, S_IRWXU);
483}
484
485bool has_kcore_dir(const char *path)
486{
487 struct dirent *d = ERR_PTR(-EINVAL);
488 const char *name = "kcore_dir";
489 DIR *dir = opendir(path);
490 size_t n = strlen(name);
491 bool result = false;
492
493 if (dir) {
494 while (d && !result) {
495 d = readdir(dir);
496 result = d ? strncmp(d->d_name, name, n) : false;
497 }
498 closedir(dir);
499 }
500
501 return result;
502}
503
504char *perf_data__kallsyms_name(struct perf_data *data)
505{
506 char *kallsyms_name;
507 struct stat st;
508
509 if (!data->is_dir)
510 return NULL;
511
512 if (asprintf(&kallsyms_name, "%s/kcore_dir/kallsyms", data->path) < 0)
513 return NULL;
514
515 if (stat(kallsyms_name, &st)) {
516 free(kallsyms_name);
517 return NULL;
518 }
519
520 return kallsyms_name;
521}
522
523char *perf_data__guest_kallsyms_name(struct perf_data *data, pid_t machine_pid)
524{
525 char *kallsyms_name;
526 struct stat st;
527
528 if (!data->is_dir)
529 return NULL;
530
531 if (asprintf(&kallsyms_name, "%s/kcore_dir__%d/kallsyms", data->path, machine_pid) < 0)
532 return NULL;
533
534 if (stat(kallsyms_name, &st)) {
535 free(kallsyms_name);
536 return NULL;
537 }
538
539 return kallsyms_name;
540}
541
542bool is_perf_data(const char *path)
543{
544 bool ret = false;
545 FILE *file;
546 u64 magic;
547
548 file = fopen(path, "r");
549 if (!file)
550 return false;
551
552 if (fread(&magic, 1, 8, file) < 8)
553 goto out;
554
555 ret = is_perf_magic(magic);
556out:
557 fclose(file);
558 return ret;
559}
1#include <linux/compiler.h>
2#include <linux/kernel.h>
3#include <sys/types.h>
4#include <sys/stat.h>
5#include <unistd.h>
6#include <string.h>
7
8#include "data.h"
9#include "util.h"
10
11static bool check_pipe(struct perf_data_file *file)
12{
13 struct stat st;
14 bool is_pipe = false;
15 int fd = perf_data_file__is_read(file) ?
16 STDIN_FILENO : STDOUT_FILENO;
17
18 if (!file->path) {
19 if (!fstat(fd, &st) && S_ISFIFO(st.st_mode))
20 is_pipe = true;
21 } else {
22 if (!strcmp(file->path, "-"))
23 is_pipe = true;
24 }
25
26 if (is_pipe)
27 file->fd = fd;
28
29 return file->is_pipe = is_pipe;
30}
31
32static int check_backup(struct perf_data_file *file)
33{
34 struct stat st;
35
36 if (!stat(file->path, &st) && st.st_size) {
37 /* TODO check errors properly */
38 char oldname[PATH_MAX];
39 snprintf(oldname, sizeof(oldname), "%s.old",
40 file->path);
41 unlink(oldname);
42 rename(file->path, oldname);
43 }
44
45 return 0;
46}
47
48static int open_file_read(struct perf_data_file *file)
49{
50 struct stat st;
51 int fd;
52
53 fd = open(file->path, O_RDONLY);
54 if (fd < 0) {
55 int err = errno;
56
57 pr_err("failed to open %s: %s", file->path, strerror(err));
58 if (err == ENOENT && !strcmp(file->path, "perf.data"))
59 pr_err(" (try 'perf record' first)");
60 pr_err("\n");
61 return -err;
62 }
63
64 if (fstat(fd, &st) < 0)
65 goto out_close;
66
67 if (!file->force && st.st_uid && (st.st_uid != geteuid())) {
68 pr_err("file %s not owned by current user or root\n",
69 file->path);
70 goto out_close;
71 }
72
73 if (!st.st_size) {
74 pr_info("zero-sized file (%s), nothing to do!\n",
75 file->path);
76 goto out_close;
77 }
78
79 file->size = st.st_size;
80 return fd;
81
82 out_close:
83 close(fd);
84 return -1;
85}
86
87static int open_file_write(struct perf_data_file *file)
88{
89 int fd;
90
91 if (check_backup(file))
92 return -1;
93
94 fd = open(file->path, O_CREAT|O_RDWR|O_TRUNC, S_IRUSR|S_IWUSR);
95
96 if (fd < 0)
97 pr_err("failed to open %s : %s\n", file->path, strerror(errno));
98
99 return fd;
100}
101
102static int open_file(struct perf_data_file *file)
103{
104 int fd;
105
106 fd = perf_data_file__is_read(file) ?
107 open_file_read(file) : open_file_write(file);
108
109 file->fd = fd;
110 return fd < 0 ? -1 : 0;
111}
112
113int perf_data_file__open(struct perf_data_file *file)
114{
115 if (check_pipe(file))
116 return 0;
117
118 if (!file->path)
119 file->path = "perf.data";
120
121 return open_file(file);
122}
123
124void perf_data_file__close(struct perf_data_file *file)
125{
126 close(file->fd);
127}
128
129ssize_t perf_data_file__write(struct perf_data_file *file,
130 void *buf, size_t size)
131{
132 return writen(file->fd, buf, size);
133}