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 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 30 void perf_data__close_dir(struct perf_data *data) 31 { 32 close_dir(data->dir.files, data->dir.nr); 33 } 34 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 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 } 134 135 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 } 154 155 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 } 175 176 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 } 209 210 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 } 219 220 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 } 260 261 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 } 275 276 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 } 291 292 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 } 300 301 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 } 324 325 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 } 342 343 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 } 351 352 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 } 357 358 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 } 363 364 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 } 403 404 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