| 1 | /* |
| 2 | * Copyright (C) 2011 David Goulet <dgoulet@efficios.com> |
| 3 | * Copyright (C) 2014 Jan Glauber <jan.glauber@gmail.com> |
| 4 | * |
| 5 | * SPDX-License-Identifier: GPL-2.0-only |
| 6 | * |
| 7 | */ |
| 8 | |
| 9 | /** |
| 10 | * @file modprobe.c |
| 11 | * |
| 12 | * @brief modprobe related functions. |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #define _LGPL_SOURCE |
| 17 | #include <assert.h> |
| 18 | #include <stdio.h> |
| 19 | #include <stdlib.h> |
| 20 | #include <sys/wait.h> |
| 21 | |
| 22 | #include <common/common.h> |
| 23 | #include <common/utils.h> |
| 24 | |
| 25 | #include "modprobe.h" |
| 26 | #include "kern-modules.h" |
| 27 | #include "lttng-sessiond.h" |
| 28 | |
| 29 | /* LTTng kernel tracer mandatory core modules list */ |
| 30 | struct kern_modules_param kern_modules_control_core[] = { |
| 31 | { |
| 32 | .name = (char *) "lttng-ring-buffer-client-discard", |
| 33 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 34 | }, |
| 35 | { |
| 36 | .name = (char *) "lttng-ring-buffer-client-overwrite", |
| 37 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 38 | }, |
| 39 | { |
| 40 | .name = (char *) "lttng-ring-buffer-metadata-client", |
| 41 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 42 | }, |
| 43 | { |
| 44 | .name = (char *) "lttng-ring-buffer-client-mmap-discard", |
| 45 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 46 | }, |
| 47 | { |
| 48 | .name = (char *) "lttng-ring-buffer-client-mmap-overwrite", |
| 49 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 50 | }, |
| 51 | { |
| 52 | .name = (char *) "lttng-ring-buffer-metadata-mmap-client", |
| 53 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED, |
| 54 | }, |
| 55 | { |
| 56 | .name = (char *) "lttng-ring-buffer-event_notifier-client", |
| 57 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 58 | }, |
| 59 | }; |
| 60 | |
| 61 | /* LTTng kerneltracer probe modules list */ |
| 62 | struct kern_modules_param kern_modules_probes_default[] = { |
| 63 | { |
| 64 | .name = (char *) "lttng-probe-asoc", |
| 65 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 66 | }, |
| 67 | { |
| 68 | .name = (char *) "lttng-probe-block", |
| 69 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 70 | }, |
| 71 | { |
| 72 | .name = (char *) "lttng-probe-btrfs", |
| 73 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 74 | }, |
| 75 | { |
| 76 | .name = (char *) "lttng-probe-compaction", |
| 77 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 78 | }, |
| 79 | { |
| 80 | .name = (char *) "lttng-probe-ext3", |
| 81 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 82 | }, |
| 83 | { |
| 84 | .name = (char *) "lttng-probe-ext4", |
| 85 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 86 | }, |
| 87 | { |
| 88 | .name = (char *) "lttng-probe-gpio", |
| 89 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 90 | }, |
| 91 | { |
| 92 | .name = (char *) "lttng-probe-i2c", |
| 93 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 94 | }, |
| 95 | { |
| 96 | .name = (char *) "lttng-probe-irq", |
| 97 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 98 | }, |
| 99 | { |
| 100 | .name = (char *) "lttng-probe-jbd", |
| 101 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 102 | }, |
| 103 | { |
| 104 | .name = (char *) "lttng-probe-jbd2", |
| 105 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 106 | }, |
| 107 | { |
| 108 | .name = (char *) "lttng-probe-kmem", |
| 109 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 110 | }, |
| 111 | { |
| 112 | .name = (char *) "lttng-probe-kvm", |
| 113 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 114 | }, |
| 115 | { |
| 116 | .name = (char *) "lttng-probe-kvm-x86", |
| 117 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 118 | }, |
| 119 | { |
| 120 | .name = (char *) "lttng-probe-kvm-x86-mmu", |
| 121 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 122 | }, |
| 123 | { |
| 124 | .name = (char *) "lttng-probe-lock", |
| 125 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 126 | }, |
| 127 | { |
| 128 | .name = (char *) "lttng-probe-module", |
| 129 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 130 | }, |
| 131 | { |
| 132 | .name = (char *) "lttng-probe-napi", |
| 133 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 134 | }, |
| 135 | { |
| 136 | .name = (char *) "lttng-probe-net", |
| 137 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 138 | }, |
| 139 | { |
| 140 | .name = (char *) "lttng-probe-power", |
| 141 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 142 | }, |
| 143 | { |
| 144 | .name = (char *) "lttng-probe-preemptirq", |
| 145 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 146 | }, |
| 147 | { |
| 148 | .name = (char *) "lttng-probe-printk", |
| 149 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 150 | }, |
| 151 | { |
| 152 | .name = (char *) "lttng-probe-random", |
| 153 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 154 | }, |
| 155 | { |
| 156 | .name = (char *) "lttng-probe-rcu", |
| 157 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 158 | }, |
| 159 | { |
| 160 | .name = (char *) "lttng-probe-regmap", |
| 161 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 162 | }, |
| 163 | { |
| 164 | .name = (char *) "lttng-probe-regulator", |
| 165 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 166 | }, |
| 167 | { |
| 168 | .name = (char *) "lttng-probe-rpm", |
| 169 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 170 | }, |
| 171 | { |
| 172 | .name = (char *) "lttng-probe-sched", |
| 173 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 174 | }, |
| 175 | { |
| 176 | .name = (char *) "lttng-probe-scsi", |
| 177 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 178 | }, |
| 179 | { |
| 180 | .name = (char *) "lttng-probe-signal", |
| 181 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 182 | }, |
| 183 | { |
| 184 | .name = (char *) "lttng-probe-skb", |
| 185 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 186 | }, |
| 187 | { |
| 188 | .name = (char *) "lttng-probe-sock", |
| 189 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 190 | }, |
| 191 | { |
| 192 | .name = (char *) "lttng-probe-statedump", |
| 193 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 194 | }, |
| 195 | { |
| 196 | .name = (char *) "lttng-probe-sunrpc", |
| 197 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 198 | }, |
| 199 | { |
| 200 | .name = (char *) "lttng-probe-timer", |
| 201 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 202 | }, |
| 203 | { |
| 204 | .name = (char *) "lttng-probe-udp", |
| 205 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 206 | }, |
| 207 | { |
| 208 | .name = (char *) "lttng-probe-vmscan", |
| 209 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 210 | }, |
| 211 | { |
| 212 | .name = (char *) "lttng-probe-v4l2", |
| 213 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 214 | }, |
| 215 | { |
| 216 | .name = (char *) "lttng-probe-workqueue", |
| 217 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 218 | }, |
| 219 | { |
| 220 | .name = (char *) "lttng-probe-writeback", |
| 221 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 222 | }, |
| 223 | { |
| 224 | .name = (char *) "lttng-probe-x86-irq-vectors", |
| 225 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 226 | }, |
| 227 | { |
| 228 | .name = (char *) "lttng-probe-x86-exceptions", |
| 229 | .load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL, |
| 230 | }, |
| 231 | }; |
| 232 | |
| 233 | /* dynamic probe modules list */ |
| 234 | static struct kern_modules_param *probes; |
| 235 | static int nr_probes; |
| 236 | static int probes_capacity; |
| 237 | |
| 238 | #if HAVE_KMOD |
| 239 | #include <libkmod.h> |
| 240 | |
| 241 | /** |
| 242 | * @brief Logging function for libkmod integration. |
| 243 | */ |
| 244 | static void log_kmod(void *data, int priority, const char *file, int line, |
| 245 | const char *fn, const char *format, va_list args) |
| 246 | { |
| 247 | char *str; |
| 248 | |
| 249 | if (vasprintf(&str, format, args) < 0) { |
| 250 | return; |
| 251 | } |
| 252 | |
| 253 | DBG("libkmod: %s", str); |
| 254 | free(str); |
| 255 | } |
| 256 | |
| 257 | /** |
| 258 | * @brief Setup the libkmod context. |
| 259 | * |
| 260 | * Create the context, add a custom logging function and preload the |
| 261 | * ressources for faster operation. |
| 262 | * |
| 263 | * @returns \c 0 on success |
| 264 | * \c < 0 on error |
| 265 | */ |
| 266 | static int setup_kmod_ctx(struct kmod_ctx **ctx) |
| 267 | { |
| 268 | int ret = 0; |
| 269 | |
| 270 | *ctx = kmod_new(NULL, NULL); |
| 271 | if (!ctx) { |
| 272 | PERROR("Unable to create kmod library context"); |
| 273 | ret = -ENOMEM; |
| 274 | goto error; |
| 275 | } |
| 276 | |
| 277 | kmod_set_log_fn(*ctx, log_kmod, NULL); |
| 278 | ret = kmod_load_resources(*ctx); |
| 279 | if (ret < 0) { |
| 280 | ERR("Failed to load kmod library resources"); |
| 281 | goto error; |
| 282 | } |
| 283 | |
| 284 | error: |
| 285 | return ret; |
| 286 | } |
| 287 | |
| 288 | /** |
| 289 | * @brief Loads the kernel modules in \p modules |
| 290 | * |
| 291 | * @param modules List of modules to load |
| 292 | * @param entries Number of modules in the list |
| 293 | * |
| 294 | * If the modules are required, we will return with error after the |
| 295 | * first failed module load, otherwise we continue loading. |
| 296 | * |
| 297 | * @returns \c 0 on success |
| 298 | * \c < 0 on error |
| 299 | */ |
| 300 | static int modprobe_lttng(struct kern_modules_param *modules, |
| 301 | int entries) |
| 302 | { |
| 303 | int ret = 0, i; |
| 304 | struct kmod_ctx *ctx; |
| 305 | |
| 306 | ret = setup_kmod_ctx(&ctx); |
| 307 | if (ret < 0) { |
| 308 | goto error; |
| 309 | } |
| 310 | |
| 311 | for (i = 0; i < entries; i++) { |
| 312 | struct kmod_module *mod = NULL; |
| 313 | |
| 314 | ret = kmod_module_new_from_name(ctx, modules[i].name, &mod); |
| 315 | if (ret < 0) { |
| 316 | PERROR("Failed to create kmod module for %s", modules[i].name); |
| 317 | goto error; |
| 318 | } |
| 319 | |
| 320 | ret = kmod_module_probe_insert_module(mod, 0, |
| 321 | NULL, NULL, NULL, NULL); |
| 322 | if (ret == -EEXIST) { |
| 323 | DBG("Module %s is already loaded", modules[i].name); |
| 324 | ret = 0; |
| 325 | } else if (ret < 0) { |
| 326 | if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) { |
| 327 | ERR("Unable to load required module %s", |
| 328 | modules[i].name); |
| 329 | goto error; |
| 330 | } else { |
| 331 | DBG("Unable to load optional module %s; continuing", |
| 332 | modules[i].name); |
| 333 | ret = 0; |
| 334 | } |
| 335 | } else { |
| 336 | DBG("Modprobe successfully %s", modules[i].name); |
| 337 | modules[i].loaded = true; |
| 338 | } |
| 339 | |
| 340 | kmod_module_unref(mod); |
| 341 | } |
| 342 | |
| 343 | error: |
| 344 | if (ctx) { |
| 345 | kmod_unref(ctx); |
| 346 | } |
| 347 | return ret; |
| 348 | } |
| 349 | |
| 350 | /** |
| 351 | * @brief Recursively unload modules. |
| 352 | * |
| 353 | * This function implements the same modules unloading behavior as |
| 354 | * 'modprobe -r' or rmmod, it will recursevily go trought the \p module |
| 355 | * dependencies and unload modules with a refcount of 0. |
| 356 | * |
| 357 | * @param mod The module to unload |
| 358 | * |
| 359 | * @returns \c 0 on success |
| 360 | * \c < 0 on error |
| 361 | */ |
| 362 | static int rmmod_recurse(struct kmod_module *mod) { |
| 363 | int ret = 0; |
| 364 | struct kmod_list *deps, *itr; |
| 365 | |
| 366 | if (kmod_module_get_initstate(mod) == KMOD_MODULE_BUILTIN) { |
| 367 | DBG("Module %s is builtin", kmod_module_get_name(mod)); |
| 368 | return ret; |
| 369 | } |
| 370 | |
| 371 | ret = kmod_module_remove_module(mod, 0); |
| 372 | |
| 373 | deps = kmod_module_get_dependencies(mod); |
| 374 | if (deps != NULL) { |
| 375 | kmod_list_foreach(itr, deps) { |
| 376 | struct kmod_module *dep = kmod_module_get_module(itr); |
| 377 | if (kmod_module_get_refcnt(dep) == 0) { |
| 378 | DBG("Recursive remove module %s", |
| 379 | kmod_module_get_name(dep)); |
| 380 | rmmod_recurse(dep); |
| 381 | } |
| 382 | kmod_module_unref(dep); |
| 383 | } |
| 384 | kmod_module_unref_list(deps); |
| 385 | } |
| 386 | |
| 387 | return ret; |
| 388 | } |
| 389 | |
| 390 | /** |
| 391 | * @brief Unloads the kernel modules in \p modules |
| 392 | * |
| 393 | * @param modules List of modules to unload |
| 394 | * @param entries Number of modules in the list |
| 395 | * |
| 396 | */ |
| 397 | static void modprobe_remove_lttng(const struct kern_modules_param *modules, |
| 398 | int entries) |
| 399 | { |
| 400 | int ret = 0, i; |
| 401 | struct kmod_ctx *ctx; |
| 402 | |
| 403 | ret = setup_kmod_ctx(&ctx); |
| 404 | if (ret < 0) { |
| 405 | goto error; |
| 406 | } |
| 407 | |
| 408 | for (i = entries - 1; i >= 0; i--) { |
| 409 | struct kmod_module *mod = NULL; |
| 410 | |
| 411 | if (!modules[i].loaded) { |
| 412 | continue; |
| 413 | } |
| 414 | |
| 415 | ret = kmod_module_new_from_name(ctx, modules[i].name, &mod); |
| 416 | if (ret < 0) { |
| 417 | PERROR("Failed to create kmod module for %s", modules[i].name); |
| 418 | goto error; |
| 419 | } |
| 420 | |
| 421 | ret = rmmod_recurse(mod); |
| 422 | if (ret == -EEXIST) { |
| 423 | DBG("Module %s is not in kernel.", modules[i].name); |
| 424 | } else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && ret < 0) { |
| 425 | ERR("Unable to remove module %s", modules[i].name); |
| 426 | } else { |
| 427 | DBG("Modprobe removal successful %s", |
| 428 | modules[i].name); |
| 429 | } |
| 430 | |
| 431 | kmod_module_unref(mod); |
| 432 | } |
| 433 | |
| 434 | error: |
| 435 | if (ctx) { |
| 436 | kmod_unref(ctx); |
| 437 | } |
| 438 | } |
| 439 | |
| 440 | #else /* HAVE_KMOD */ |
| 441 | |
| 442 | static int modprobe_lttng(struct kern_modules_param *modules, |
| 443 | int entries) |
| 444 | { |
| 445 | int ret = 0, i; |
| 446 | char modprobe[256]; |
| 447 | |
| 448 | for (i = 0; i < entries; i++) { |
| 449 | ret = snprintf(modprobe, sizeof(modprobe), |
| 450 | "/sbin/modprobe %s%s", |
| 451 | modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED ? "" : "-q ", |
| 452 | modules[i].name); |
| 453 | if (ret < 0) { |
| 454 | PERROR("snprintf modprobe"); |
| 455 | goto error; |
| 456 | } |
| 457 | modprobe[sizeof(modprobe) - 1] = '\0'; |
| 458 | ret = system(modprobe); |
| 459 | if (ret == -1) { |
| 460 | if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) { |
| 461 | ERR("Unable to launch modprobe for required module %s", |
| 462 | modules[i].name); |
| 463 | goto error; |
| 464 | } else { |
| 465 | DBG("Unable to launch modprobe for optional module %s; continuing", |
| 466 | modules[i].name); |
| 467 | ret = 0; |
| 468 | } |
| 469 | } else if (WEXITSTATUS(ret) != 0) { |
| 470 | if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) { |
| 471 | ERR("Unable to load required module %s", |
| 472 | modules[i].name); |
| 473 | goto error; |
| 474 | } else { |
| 475 | DBG("Unable to load optional module %s; continuing", |
| 476 | modules[i].name); |
| 477 | ret = 0; |
| 478 | } |
| 479 | } else { |
| 480 | DBG("Modprobe successfully %s", modules[i].name); |
| 481 | modules[i].loaded = true; |
| 482 | } |
| 483 | } |
| 484 | |
| 485 | error: |
| 486 | return ret; |
| 487 | } |
| 488 | |
| 489 | static void modprobe_remove_lttng(const struct kern_modules_param *modules, |
| 490 | int entries) |
| 491 | { |
| 492 | int ret = 0, i; |
| 493 | char modprobe[256]; |
| 494 | |
| 495 | for (i = entries - 1; i >= 0; i--) { |
| 496 | if (!modules[i].loaded) { |
| 497 | continue; |
| 498 | } |
| 499 | ret = snprintf(modprobe, sizeof(modprobe), |
| 500 | "/sbin/modprobe -r -q %s", |
| 501 | modules[i].name); |
| 502 | if (ret < 0) { |
| 503 | PERROR("snprintf modprobe -r"); |
| 504 | return; |
| 505 | } |
| 506 | modprobe[sizeof(modprobe) - 1] = '\0'; |
| 507 | ret = system(modprobe); |
| 508 | if (ret == -1) { |
| 509 | ERR("Unable to launch modprobe -r for module %s", |
| 510 | modules[i].name); |
| 511 | } else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && WEXITSTATUS(ret) != 0) { |
| 512 | ERR("Unable to remove module %s", |
| 513 | modules[i].name); |
| 514 | } else { |
| 515 | DBG("Modprobe removal successful %s", |
| 516 | modules[i].name); |
| 517 | } |
| 518 | } |
| 519 | } |
| 520 | |
| 521 | #endif /* HAVE_KMOD */ |
| 522 | |
| 523 | /* |
| 524 | * Remove control kernel module(s) in reverse load order. |
| 525 | */ |
| 526 | void modprobe_remove_lttng_control(void) |
| 527 | { |
| 528 | modprobe_remove_lttng(kern_modules_control_core, |
| 529 | ARRAY_SIZE(kern_modules_control_core)); |
| 530 | } |
| 531 | |
| 532 | static void free_probes(void) |
| 533 | { |
| 534 | int i; |
| 535 | |
| 536 | if (!probes) { |
| 537 | return; |
| 538 | } |
| 539 | for (i = 0; i < nr_probes; ++i) { |
| 540 | free(probes[i].name); |
| 541 | } |
| 542 | free(probes); |
| 543 | probes = NULL; |
| 544 | nr_probes = 0; |
| 545 | } |
| 546 | |
| 547 | /* |
| 548 | * Remove data kernel modules in reverse load order. |
| 549 | */ |
| 550 | void modprobe_remove_lttng_data(void) |
| 551 | { |
| 552 | if (!probes) { |
| 553 | return; |
| 554 | } |
| 555 | |
| 556 | modprobe_remove_lttng(probes, nr_probes); |
| 557 | free_probes(); |
| 558 | } |
| 559 | |
| 560 | /* |
| 561 | * Remove all kernel modules in reverse order. |
| 562 | */ |
| 563 | void modprobe_remove_lttng_all(void) |
| 564 | { |
| 565 | modprobe_remove_lttng_data(); |
| 566 | modprobe_remove_lttng_control(); |
| 567 | } |
| 568 | |
| 569 | /* |
| 570 | * Load control kernel module(s). |
| 571 | */ |
| 572 | int modprobe_lttng_control(void) |
| 573 | { |
| 574 | return modprobe_lttng(kern_modules_control_core, |
| 575 | ARRAY_SIZE(kern_modules_control_core)); |
| 576 | } |
| 577 | |
| 578 | /** |
| 579 | * Grow global list of probes (double capacity or set it to 1 if |
| 580 | * currently 0 and copy existing data). |
| 581 | */ |
| 582 | static int grow_probes(void) |
| 583 | { |
| 584 | int i; |
| 585 | struct kern_modules_param *tmp_probes; |
| 586 | |
| 587 | /* Initialize capacity to 1 if 0. */ |
| 588 | if (probes_capacity == 0) { |
| 589 | probes = zmalloc(sizeof(*probes)); |
| 590 | if (!probes) { |
| 591 | PERROR("malloc probe list"); |
| 592 | return -ENOMEM; |
| 593 | } |
| 594 | |
| 595 | probes_capacity = 1; |
| 596 | return 0; |
| 597 | } |
| 598 | |
| 599 | /* Double size. */ |
| 600 | probes_capacity *= 2; |
| 601 | |
| 602 | tmp_probes = zmalloc(sizeof(*tmp_probes) * probes_capacity); |
| 603 | if (!tmp_probes) { |
| 604 | PERROR("malloc probe list"); |
| 605 | return -ENOMEM; |
| 606 | } |
| 607 | |
| 608 | for (i = 0; i < nr_probes; ++i) { |
| 609 | /* Ownership of 'name' field is transferred. */ |
| 610 | tmp_probes[i] = probes[i]; |
| 611 | } |
| 612 | |
| 613 | /* Replace probes with larger copy. */ |
| 614 | free(probes); |
| 615 | probes = tmp_probes; |
| 616 | |
| 617 | return 0; |
| 618 | } |
| 619 | |
| 620 | /* |
| 621 | * Appends a comma-separated list of probes to the global list |
| 622 | * of probes. |
| 623 | */ |
| 624 | static int append_list_to_probes(const char *list) |
| 625 | { |
| 626 | char *next; |
| 627 | int ret; |
| 628 | char *tmp_list, *cur_list, *saveptr; |
| 629 | |
| 630 | assert(list); |
| 631 | |
| 632 | cur_list = tmp_list = strdup(list); |
| 633 | if (!tmp_list) { |
| 634 | PERROR("strdup temp list"); |
| 635 | return -ENOMEM; |
| 636 | } |
| 637 | |
| 638 | for (;;) { |
| 639 | size_t name_len; |
| 640 | struct kern_modules_param *cur_mod; |
| 641 | |
| 642 | next = strtok_r(cur_list, ",", &saveptr); |
| 643 | if (!next) { |
| 644 | break; |
| 645 | } |
| 646 | cur_list = NULL; |
| 647 | |
| 648 | /* filter leading spaces */ |
| 649 | while (*next == ' ') { |
| 650 | next++; |
| 651 | } |
| 652 | |
| 653 | if (probes_capacity <= nr_probes) { |
| 654 | ret = grow_probes(); |
| 655 | if (ret) { |
| 656 | goto error; |
| 657 | } |
| 658 | } |
| 659 | |
| 660 | /* Length 13 is "lttng-probe-" + \0 */ |
| 661 | name_len = strlen(next) + 13; |
| 662 | |
| 663 | cur_mod = &probes[nr_probes]; |
| 664 | cur_mod->name = zmalloc(name_len); |
| 665 | if (!cur_mod->name) { |
| 666 | PERROR("malloc probe list"); |
| 667 | ret = -ENOMEM; |
| 668 | goto error; |
| 669 | } |
| 670 | |
| 671 | ret = snprintf(cur_mod->name, name_len, "lttng-probe-%s", next); |
| 672 | if (ret < 0) { |
| 673 | PERROR("snprintf modprobe name"); |
| 674 | ret = -ENOMEM; |
| 675 | goto error; |
| 676 | } |
| 677 | |
| 678 | cur_mod->load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL; |
| 679 | |
| 680 | nr_probes++; |
| 681 | } |
| 682 | |
| 683 | free(tmp_list); |
| 684 | return 0; |
| 685 | |
| 686 | error: |
| 687 | free(tmp_list); |
| 688 | free_probes(); |
| 689 | return ret; |
| 690 | } |
| 691 | |
| 692 | /* |
| 693 | * Load data kernel module(s). |
| 694 | */ |
| 695 | int modprobe_lttng_data(void) |
| 696 | { |
| 697 | int ret, i; |
| 698 | char *list; |
| 699 | |
| 700 | /* |
| 701 | * Base probes: either from command line option, environment |
| 702 | * variable or default list. |
| 703 | */ |
| 704 | list = config.kmod_probes_list.value; |
| 705 | if (list) { |
| 706 | /* User-specified probes. */ |
| 707 | ret = append_list_to_probes(list); |
| 708 | if (ret) { |
| 709 | return ret; |
| 710 | } |
| 711 | } else { |
| 712 | /* Default probes. */ |
| 713 | int def_len = ARRAY_SIZE(kern_modules_probes_default); |
| 714 | |
| 715 | probes = zmalloc(sizeof(*probes) * def_len); |
| 716 | if (!probes) { |
| 717 | PERROR("malloc probe list"); |
| 718 | return -ENOMEM; |
| 719 | } |
| 720 | |
| 721 | nr_probes = probes_capacity = def_len; |
| 722 | |
| 723 | for (i = 0; i < def_len; ++i) { |
| 724 | char* name = strdup(kern_modules_probes_default[i].name); |
| 725 | |
| 726 | if (!name) { |
| 727 | PERROR("strdup probe item"); |
| 728 | ret = -ENOMEM; |
| 729 | goto error; |
| 730 | } |
| 731 | |
| 732 | probes[i].name = name; |
| 733 | probes[i].load_policy = kern_modules_probes_default[i].load_policy; |
| 734 | } |
| 735 | } |
| 736 | |
| 737 | /* |
| 738 | * Extra modules? Append them to current probes list. |
| 739 | */ |
| 740 | list = config.kmod_extra_probes_list.value; |
| 741 | if (list) { |
| 742 | ret = append_list_to_probes(list); |
| 743 | if (ret) { |
| 744 | goto error; |
| 745 | } |
| 746 | } |
| 747 | |
| 748 | /* |
| 749 | * Load probes modules now. |
| 750 | */ |
| 751 | ret = modprobe_lttng(probes, nr_probes); |
| 752 | if (ret) { |
| 753 | goto error; |
| 754 | } |
| 755 | return ret; |
| 756 | |
| 757 | error: |
| 758 | free_probes(); |
| 759 | return ret; |
| 760 | } |