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 <sys/types.h>
7 #include <sys/stat.h>
8 #include <errno.h>
9 #include <fcntl.h>
10 #include <unistd.h>
11 #include <string.h>
12 #include <asm/bug.h>
13 #include <dirent.h>
14
15 #include "data.h"
16 #include "util.h" // rm_rf_perf_data()
17 #include "debug.h"
18 #include "header.h"
19 #include <internal/lib.h>
20
close_dir(struct perf_data_file * files,int nr)21 static void close_dir(struct perf_data_file *files, int nr)
22 {
23 while (--nr >= 1) {
24 close(files[nr].fd);
25 zfree(&files[nr].path);
26 }
27 free(files);
28 }
29
perf_data__close_dir(struct perf_data * data)30 void perf_data__close_dir(struct perf_data *data)
31 {
32 close_dir(data->dir.files, data->dir.nr);
33 }
34
perf_data__create_dir(struct perf_data * data,int nr)35 int perf_data__create_dir(struct perf_data *data, int nr)
36 {
37 struct perf_data_file *files = NULL;
38 int i, ret = -1;
39
40 if (WARN_ON(!data->is_dir))
41 return -EINVAL;
42
43 files = zalloc(nr * sizeof(*files));
44 if (!files)
45 return -ENOMEM;
46
47 data->dir.version = PERF_DIR_VERSION;
48 data->dir.files = files;
49 data->dir.nr = nr;
50
51 for (i = 0; i < nr; i++) {
52 struct perf_data_file *file = &files[i];
53
54 if (asprintf(&file->path, "%s/data.%d", data->path, i) < 0)
55 goto out_err;
56
57 ret = open(file->path, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);
58 if (ret < 0)
59 goto out_err;
60
61 file->fd = ret;
62 }
63
64 return 0;
65
66 out_err:
67 close_dir(files, i);
68 return ret;
69 }
70
perf_data__open_dir(struct perf_data * data)71 int perf_data__open_dir(struct perf_data *data)
72 {
73 struct perf_data_file *files = NULL;
74 struct dirent *dent;
75 int ret = -1;
76 DIR *dir;
77 int nr = 0;
78
79 if (WARN_ON(!data->is_dir))
80 return -EINVAL;
81
82 /* The version is provided by DIR_FORMAT feature. */
83 if (WARN_ON(data->dir.version != PERF_DIR_VERSION))
84 return -1;
85
86 dir = opendir(data->path);
87 if (!dir)
88 return -EINVAL;
89
90 while ((dent = readdir(dir)) != NULL) {
91 struct perf_data_file *file;
92 char path[PATH_MAX];
93 struct stat st;
94
95 snprintf(path, sizeof(path), "%s/%s", data->path, dent->d_name);
96 if (stat(path, &st))
97 continue;
98
99 if (!S_ISREG(st.st_mode) || strncmp(dent->d_name, "data", 4))
100 continue;
101
102 ret = -ENOMEM;
103
104 file = realloc(files, (nr + 1) * sizeof(*files));
105 if (!file)
106 goto out_err;
107
108 files = file;
109 file = &files[nr++];
110
111 file->path = strdup(path);
112 if (!file->path)
113 goto out_err;
114
115 ret = open(file->path, O_RDONLY);
116 if (ret < 0)
117 goto out_err;
118
119 file->fd = ret;
120 file->size = st.st_size;
121 }
122
123 if (!files)
124 return -EINVAL;
125
126 data->dir.files = files;
127 data->dir.nr = nr;
128 return 0;
129
130 out_err:
131 close_dir(files, nr);
132 return ret;
133 }
134
perf_data__update_dir(struct perf_data * data)135 int perf_data__update_dir(struct perf_data *data)
136 {
137 int i;
138
139 if (WARN_ON(!data->is_dir))
140 return -EINVAL;
141
142 for (i = 0; i < data->dir.nr; i++) {
143 struct perf_data_file *file = &data->dir.files[i];
144 struct stat st;
145
146 if (fstat(file->fd, &st))
147 return -1;
148
149 file->size = st.st_size;
150 }
151
152 return 0;
153 }
154
check_pipe(struct perf_data * data)155 static bool check_pipe(struct perf_data *data)
156 {
157 struct stat st;
158 bool is_pipe = false;
159 int fd = perf_data__is_read(data) ?
160 STDIN_FILENO : STDOUT_FILENO;
161
162 if (!data->path) {
163 if (!fstat(fd, &st) && S_ISFIFO(st.st_mode))
164 is_pipe = true;
165 } else {
166 if (!strcmp(data->path, "-"))
167 is_pipe = true;
168 }
169
170 if (is_pipe)
171 data->file.fd = fd;
172
173 return data->is_pipe = is_pipe;
174 }
175
check_backup(struct perf_data * data)176 static int check_backup(struct perf_data *data)
177 {
178 struct stat st;
179
180 if (perf_data__is_read(data))
181 return 0;
182
183 if (!stat(data->path, &st) && st.st_size) {
184 char oldname[PATH_MAX];
185 int ret;
186
187 snprintf(oldname, sizeof(oldname), "%s.old",
188 data->path);
189
190 ret = rm_rf_perf_data(oldname);
191 if (ret) {
192 pr_err("Can't remove old data: %s (%s)\n",
193 ret == -2 ?
194 "Unknown file found" : strerror(errno),
195 oldname);
196 return -1;
197 }
198
199 if (rename(data->path, oldname)) {
200 pr_err("Can't move data: %s (%s to %s)\n",
201 strerror(errno),
202 data->path, oldname);
203 return -1;
204 }
205 }
206
207 return 0;
208 }
209
is_dir(struct perf_data * data)210 static bool is_dir(struct perf_data *data)
211 {
212 struct stat st;
213
214 if (stat(data->path, &st))
215 return false;
216
217 return (st.st_mode & S_IFMT) == S_IFDIR;
218 }
219
open_file_read(struct perf_data * data)220 static int open_file_read(struct perf_data *data)
221 {
222 struct stat st;
223 int fd;
224 char sbuf[STRERR_BUFSIZE];
225
226 fd = open(data->file.path, O_RDONLY);
227 if (fd < 0) {
228 int err = errno;
229
230 pr_err("failed to open %s: %s", data->file.path,
231 str_error_r(err, sbuf, sizeof(sbuf)));
232 if (err == ENOENT && !strcmp(data->file.path, "perf.data"))
233 pr_err(" (try 'perf record' first)");
234 pr_err("\n");
235 return -err;
236 }
237
238 if (fstat(fd, &st) < 0)
239 goto out_close;
240
241 if (!data->force && st.st_uid && (st.st_uid != geteuid())) {
242 pr_err("File %s not owned by current user or root (use -f to override)\n",
243 data->file.path);
244 goto out_close;
245 }
246
247 if (!st.st_size) {
248 pr_info("zero-sized data (%s), nothing to do!\n",
249 data->file.path);
250 goto out_close;
251 }
252
253 data->file.size = st.st_size;
254 return fd;
255
256 out_close:
257 close(fd);
258 return -1;
259 }
260
open_file_write(struct perf_data * data)261 static int open_file_write(struct perf_data *data)
262 {
263 int fd;
264 char sbuf[STRERR_BUFSIZE];
265
266 fd = open(data->file.path, O_CREAT|O_RDWR|O_TRUNC|O_CLOEXEC,
267 S_IRUSR|S_IWUSR);
268
269 if (fd < 0)
270 pr_err("failed to open %s : %s\n", data->file.path,
271 str_error_r(errno, sbuf, sizeof(sbuf)));
272
273 return fd;
274 }
275
open_file(struct perf_data * data)276 static int open_file(struct perf_data *data)
277 {
278 int fd;
279
280 fd = perf_data__is_read(data) ?
281 open_file_read(data) : open_file_write(data);
282
283 if (fd < 0) {
284 zfree(&data->file.path);
285 return -1;
286 }
287
288 data->file.fd = fd;
289 return 0;
290 }
291
open_file_dup(struct perf_data * data)292 static int open_file_dup(struct perf_data *data)
293 {
294 data->file.path = strdup(data->path);
295 if (!data->file.path)
296 return -ENOMEM;
297
298 return open_file(data);
299 }
300
open_dir(struct perf_data * data)301 static int open_dir(struct perf_data *data)
302 {
303 int ret;
304
305 /*
306 * So far we open only the header, so we can read the data version and
307 * layout.
308 */
309 if (asprintf(&data->file.path, "%s/header", data->path) < 0)
310 return -1;
311
312 if (perf_data__is_write(data) &&
313 mkdir(data->path, S_IRWXU) < 0)
314 return -1;
315
316 ret = open_file(data);
317
318 /* Cleanup whatever we managed to create so far. */
319 if (ret && perf_data__is_write(data))
320 rm_rf_perf_data(data->path);
321
322 return ret;
323 }
324
perf_data__open(struct perf_data * data)325 int perf_data__open(struct perf_data *data)
326 {
327 if (check_pipe(data))
328 return 0;
329
330 if (!data->path)
331 data->path = "perf.data";
332
333 if (check_backup(data))
334 return -1;
335
336 if (perf_data__is_read(data))
337 data->is_dir = is_dir(data);
338
339 return perf_data__is_dir(data) ?
340 open_dir(data) : open_file_dup(data);
341 }
342
perf_data__close(struct perf_data * data)343 void perf_data__close(struct perf_data *data)
344 {
345 if (perf_data__is_dir(data))
346 perf_data__close_dir(data);
347
348 zfree(&data->file.path);
349 close(data->file.fd);
350 }
351
perf_data_file__write(struct perf_data_file * file,void * buf,size_t size)352 ssize_t perf_data_file__write(struct perf_data_file *file,
353 void *buf, size_t size)
354 {
355 return writen(file->fd, buf, size);
356 }
357
perf_data__write(struct perf_data * data,void * buf,size_t size)358 ssize_t perf_data__write(struct perf_data *data,
359 void *buf, size_t size)
360 {
361 return perf_data_file__write(&data->file, buf, size);
362 }
363
perf_data__switch(struct perf_data * data,const char * postfix,size_t pos,bool at_exit,char ** new_filepath)364 int perf_data__switch(struct perf_data *data,
365 const char *postfix,
366 size_t pos, bool at_exit,
367 char **new_filepath)
368 {
369 int ret;
370
371 if (check_pipe(data))
372 return -EINVAL;
373 if (perf_data__is_read(data))
374 return -EINVAL;
375
376 if (asprintf(new_filepath, "%s.%s", data->path, postfix) < 0)
377 return -ENOMEM;
378
379 /*
380 * Only fire a warning, don't return error, continue fill
381 * original file.
382 */
383 if (rename(data->path, *new_filepath))
384 pr_warning("Failed to rename %s to %s\n", data->path, *new_filepath);
385
386 if (!at_exit) {
387 close(data->file.fd);
388 ret = perf_data__open(data);
389 if (ret < 0)
390 goto out;
391
392 if (lseek(data->file.fd, pos, SEEK_SET) == (off_t)-1) {
393 ret = -errno;
394 pr_debug("Failed to lseek to %zu: %s",
395 pos, strerror(errno));
396 goto out;
397 }
398 }
399 ret = data->file.fd;
400 out:
401 return ret;
402 }
403
perf_data__size(struct perf_data * data)404 unsigned long perf_data__size(struct perf_data *data)
405 {
406 u64 size = data->file.size;
407 int i;
408
409 if (!data->is_dir)
410 return size;
411
412 for (i = 0; i < data->dir.nr; i++) {
413 struct perf_data_file *file = &data->dir.files[i];
414
415 size += file->size;
416 }
417
418 return size;
419 }
420