git.ozlabs.org Git - petitboot/blob - discover/device-handler.c

   1
   2 #include <assert.h>
   3 #include <stdlib.h>
   4 #include <stdbool.h>
   5 #include <unistd.h>
   6 #include <string.h>
   7 #include <errno.h>
   8 #include <mntent.h>
   9 #include <sys/stat.h>
  10 #include <sys/wait.h>
  11
  12 #include <pb-config/pb-config.h>
  13 #include <talloc/talloc.h>
  14 #include <list/list.h>
  15 #include <log/log.h>
  16 #include <types/types.h>
  17 #include <system/system.h>
  18 #include <process/process.h>
  19 #include <url/url.h>
  20
  21 #include "device-handler.h"
  22 #include "discover-server.h"
  23 #include "event.h"
  24 #include "parser.h"
  25 #include "resource.h"
  26 #include "paths.h"
  27 #include "boot.h"
  28
  29 struct device_handler {
  30         struct discover_server  *server;
  31         int                     dry_run;
  32
  33         struct discover_device  **devices;
  34         unsigned int            n_devices;
  35
  36         struct waitset          *waitset;
  37         struct waiter           *timeout_waiter;
  38         bool                    autoboot_enabled;
  39         unsigned int            sec_to_boot;
  40
  41         struct discover_boot_option *default_boot_option;
  42         struct list             unresolved_boot_options;
  43 };
  44
  45 static int mount_device(struct discover_device *dev);
  46 static int umount_device(struct discover_device *dev);
  47
  48 void discover_context_add_boot_option(struct discover_context *ctx,
  49                 struct discover_boot_option *boot_option)
  50 {
  51         boot_option->source = ctx->parser;
  52         list_add_tail(&ctx->boot_options, &boot_option->list);
  53         talloc_steal(ctx, boot_option);
  54 }
  55
  56 /**
  57  * device_handler_get_device_count - Get the count of current handler devices.
  58  */
  59
  60 int device_handler_get_device_count(const struct device_handler *handler)
  61 {
  62         return handler->n_devices;
  63 }
  64
  65 /**
  66  * device_handler_get_device - Get a handler device by index.
  67  */
  68
  69 const struct discover_device *device_handler_get_device(
  70         const struct device_handler *handler, unsigned int index)
  71 {
  72         if (index >= handler->n_devices) {
  73                 assert(0 && "bad index");
  74                 return NULL;
  75         }
  76
  77         return handler->devices[index];
  78 }
  79
  80 struct discover_boot_option *discover_boot_option_create(
  81                 struct discover_context *ctx,
  82                 struct discover_device *device)
  83 {
  84         struct discover_boot_option *opt;
  85
  86         opt = talloc_zero(ctx, struct discover_boot_option);
  87         opt->option = talloc_zero(opt, struct boot_option);
  88         opt->device = device;
  89
  90         return opt;
  91 }
  92
  93 static int device_match_uuid(struct discover_device *dev, const char *uuid)
  94 {
  95         return dev->uuid && !strcmp(dev->uuid, uuid);
  96 }
  97
  98 static int device_match_label(struct discover_device *dev, const char *label)
  99 {
 100         return dev->label && !strcmp(dev->label, label);
 101 }
 102
 103 static int device_match_id(struct discover_device *dev, const char *id)
 104 {
 105         return !strcmp(dev->device->id, id);
 106 }
 107
 108 static int device_match_serial(struct discover_device *dev, const char *serial)
 109 {
 110         const char *val = discover_device_get_param(dev, "ID_SERIAL");
 111         return val && !strcmp(val, serial);
 112 }
 113
 114 static struct discover_device *device_lookup(
 115                 struct device_handler *device_handler,
 116                 int (match_fn)(struct discover_device *, const char *),
 117                 const char *str)
 118 {
 119         struct discover_device *dev;
 120         unsigned int i;
 121
 122         if (!str)
 123                 return NULL;
 124
 125         for (i = 0; i < device_handler->n_devices; i++) {
 126                 dev = device_handler->devices[i];
 127
 128                 if (match_fn(dev, str))
 129                         return dev;
 130         }
 131
 132         return NULL;
 133 }
 134
 135 struct discover_device *device_lookup_by_name(struct device_handler *handler,
 136                 const char *name)
 137 {
 138         if (!strncmp(name, "/dev/", strlen("/dev/")))
 139                 name += strlen("/dev/");
 140
 141         return device_lookup_by_id(handler, name);
 142 }
 143
 144 struct discover_device *device_lookup_by_uuid(
 145                 struct device_handler *device_handler,
 146                 const char *uuid)
 147 {
 148         return device_lookup(device_handler, device_match_uuid, uuid);
 149 }
 150
 151 struct discover_device *device_lookup_by_label(
 152                 struct device_handler *device_handler,
 153                 const char *label)
 154 {
 155         return device_lookup(device_handler, device_match_label, label);
 156 }
 157
 158 struct discover_device *device_lookup_by_id(
 159                 struct device_handler *device_handler,
 160                 const char *id)
 161 {
 162         return device_lookup(device_handler, device_match_id, id);
 163 }
 164
 165 struct discover_device *device_lookup_by_serial(
 166                 struct device_handler *device_handler,
 167                 const char *serial)
 168 {
 169         return device_lookup(device_handler, device_match_serial, serial);
 170 }
 171
 172 void device_handler_destroy(struct device_handler *handler)
 173 {
 174         talloc_free(handler);
 175 }
 176
 177 static int destroy_device(void *arg)
 178 {
 179         struct discover_device *dev = arg;
 180
 181         umount_device(dev);
 182
 183         return 0;
 184 }
 185
 186 struct discover_device *discover_device_create(struct device_handler *handler,
 187                 const char *id)
 188 {
 189         struct discover_device *dev;
 190
 191         dev = device_lookup_by_id(handler, id);
 192         if (dev)
 193                 return dev;
 194
 195         dev = talloc_zero(handler, struct discover_device);
 196         dev->device = talloc_zero(dev, struct device);
 197         dev->device->id = talloc_strdup(dev->device, id);
 198         list_init(&dev->params);
 199         list_init(&dev->boot_options);
 200
 201         talloc_set_destructor(dev, destroy_device);
 202
 203         return dev;
 204 }
 205
 206 struct discover_device_param {
 207         char                    *name;
 208         char                    *value;
 209         struct list_item        list;
 210 };
 211
 212 void discover_device_set_param(struct discover_device *device,
 213                 const char *name, const char *value)
 214 {
 215         struct discover_device_param *param;
 216         bool found = false;
 217
 218         list_for_each_entry(&device->params, param, list) {
 219                 if (!strcmp(param->name, name)) {
 220                         found = true;
 221                         break;
 222                 }
 223         }
 224
 225         if (!found) {
 226                 if (!value)
 227                         return;
 228                 param = talloc(device, struct discover_device_param);
 229                 param->name = talloc_strdup(param, name);
 230                 list_add(&device->params, &param->list);
 231         } else {
 232                 if (!value) {
 233                         list_remove(&param->list);
 234                         talloc_free(param);
 235                         return;
 236                 }
 237                 talloc_free(param->value);
 238         }
 239
 240         param->value = talloc_strdup(param, value);
 241 }
 242
 243 const char *discover_device_get_param(struct discover_device *device,
 244                 const char *name)
 245 {
 246         struct discover_device_param *param;
 247
 248         list_for_each_entry(&device->params, param, list) {
 249                 if (!strcmp(param->name, name))
 250                         return param->name;
 251         }
 252         return NULL;
 253 }
 254
 255 struct device_handler *device_handler_init(struct discover_server *server,
 256                 struct waitset *waitset, int dry_run)
 257 {
 258         struct device_handler *handler;
 259
 260         handler = talloc_zero(NULL, struct device_handler);
 261         handler->server = server;
 262         handler->waitset = waitset;
 263         handler->dry_run = dry_run;
 264         handler->autoboot_enabled = config_get()->autoboot_enabled;
 265
 266         list_init(&handler->unresolved_boot_options);
 267
 268         /* set up our mount point base */
 269         pb_mkdir_recursive(mount_base());
 270
 271         parser_init();
 272
 273         return handler;
 274 }
 275
 276 void device_handler_remove(struct device_handler *handler,
 277                 struct discover_device *device)
 278 {
 279         unsigned int i;
 280
 281         for (i = 0; i < handler->n_devices; i++)
 282                 if (handler->devices[i] == device)
 283                         break;
 284
 285         if (i == handler->n_devices) {
 286                 talloc_free(device);
 287                 return;
 288         }
 289
 290         handler->n_devices--;
 291         memmove(&handler->devices[i], &handler->devices[i + 1],
 292                 (handler->n_devices - i) * sizeof(handler->devices[0]));
 293         handler->devices = talloc_realloc(handler, handler->devices,
 294                 struct discover_device *, handler->n_devices);
 295
 296         if (device->notified)
 297                 discover_server_notify_device_remove(handler->server,
 298                                                         device->device);
 299
 300         talloc_free(device);
 301 }
 302
 303 static void boot_status(void *arg, struct boot_status *status)
 304 {
 305         struct device_handler *handler = arg;
 306
 307         discover_server_notify_boot_status(handler->server, status);
 308 }
 309
 310 static void countdown_status(struct device_handler *handler,
 311                 struct discover_boot_option *opt, unsigned int sec)
 312 {
 313         struct boot_status status;
 314
 315         status.type = BOOT_STATUS_INFO;
 316         status.progress = -1;
 317         status.detail = NULL;
 318         status.message = talloc_asprintf(handler,
 319                         "Booting %s in %u sec", opt->option->name, sec);
 320
 321         discover_server_notify_boot_status(handler->server, &status);
 322
 323         talloc_free(status.message);
 324 }
 325
 326 static int default_timeout(void *arg)
 327 {
 328         struct device_handler *handler = arg;
 329         struct discover_boot_option *opt;
 330
 331         if (!handler->default_boot_option)
 332                 return 0;
 333
 334         opt = handler->default_boot_option;
 335
 336         if (handler->sec_to_boot) {
 337                 countdown_status(handler, opt, handler->sec_to_boot);
 338                 handler->sec_to_boot--;
 339                 handler->timeout_waiter = waiter_register_timeout(
 340                                                 handler->waitset, 1000,
 341                                                 default_timeout, handler);
 342                 return 0;
 343         }
 344
 345         handler->timeout_waiter = NULL;
 346
 347         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 348
 349         boot(handler, handler->default_boot_option, NULL,
 350                         handler->dry_run, boot_status, handler);
 351         return 0;
 352 }
 353
 354 static bool priority_match(struct boot_priority *prio,
 355                 struct discover_boot_option *opt)
 356 {
 357         return prio->type == opt->device->device->type;
 358 }
 359
 360 static int default_option_priority(struct discover_boot_option *opt)
 361 {
 362         const struct config *config;
 363         struct boot_priority *prio;
 364         int i;
 365
 366         config = config_get();
 367
 368         for (i = 0; i < config->n_boot_priorities; i++) {
 369                 prio = &config->boot_priorities[i];
 370                 if (priority_match(prio, opt))
 371                         break;
 372         }
 373
 374         return i;
 375 }
 376
 377 static void set_default(struct device_handler *handler,
 378                 struct discover_boot_option *opt)
 379 {
 380         if (!handler->autoboot_enabled)
 381                 return;
 382
 383         /* Resolve any conflicts: if we have a new default option, it only
 384          * replaces the current if it has a higher priority. */
 385         if (handler->default_boot_option) {
 386                 int new_prio, cur_prio;
 387
 388                 new_prio = default_option_priority(opt);
 389                 cur_prio = default_option_priority(
 390                                         handler->default_boot_option);
 391
 392                 if (new_prio < cur_prio) {
 393                         handler->default_boot_option = opt;
 394                         /* extend the timeout a little, so the user sees some
 395                          * indication of the change */
 396                         handler->sec_to_boot += 2;
 397                 }
 398
 399                 return;
 400         }
 401
 402         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
 403         handler->default_boot_option = opt;
 404
 405         pb_log("Boot option %s set as default, timeout %u sec.\n",
 406                opt->option->id, handler->sec_to_boot);
 407
 408         default_timeout(handler);
 409 }
 410
 411 static bool resource_is_resolved(struct resource *res)
 412 {
 413         return !res || res->resolved;
 414 }
 415
 416 /* We only use this in an assert, which will disappear if we're compiling
 417  * with NDEBUG, so we need the 'used' attribute for these builds */
 418 static bool __attribute__((used)) boot_option_is_resolved(
 419                 struct discover_boot_option *opt)
 420 {
 421         return resource_is_resolved(opt->boot_image) &&
 422                 resource_is_resolved(opt->initrd) &&
 423                 resource_is_resolved(opt->dtb) &&
 424                 resource_is_resolved(opt->icon);
 425 }
 426
 427 static bool resource_resolve(struct resource *res, const char *name,
 428                 struct discover_boot_option *opt,
 429                 struct device_handler *handler)
 430 {
 431         struct parser *parser = opt->source;
 432
 433         if (resource_is_resolved(res))
 434                 return true;
 435
 436         pb_log("Attempting to resolve resource %s->%s with parser %s\n",
 437                         opt->option->id, name, parser->name);
 438         parser->resolve_resource(handler, res);
 439
 440         return res->resolved;
 441 }
 442
 443 static bool boot_option_resolve(struct discover_boot_option *opt,
 444                 struct device_handler *handler)
 445 {
 446         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
 447                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
 448                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
 449                 resource_resolve(opt->icon, "icon", opt, handler);
 450 }
 451
 452 static void boot_option_finalise(struct device_handler *handler,
 453                 struct discover_boot_option *opt)
 454 {
 455         assert(boot_option_is_resolved(opt));
 456
 457         /* check that the parsers haven't set any of the final data */
 458         assert(!opt->option->boot_image_file);
 459         assert(!opt->option->initrd_file);
 460         assert(!opt->option->dtb_file);
 461         assert(!opt->option->icon_file);
 462         assert(!opt->option->device_id);
 463
 464         if (opt->boot_image)
 465                 opt->option->boot_image_file = opt->boot_image->url->full;
 466         if (opt->initrd)
 467                 opt->option->initrd_file = opt->initrd->url->full;
 468         if (opt->dtb)
 469                 opt->option->dtb_file = opt->dtb->url->full;
 470         if (opt->icon)
 471                 opt->option->icon_file = opt->icon->url->full;
 472
 473         opt->option->device_id = opt->device->device->id;
 474
 475         if (opt->option->is_default)
 476                 set_default(handler, opt);
 477 }
 478
 479 static void notify_boot_option(struct device_handler *handler,
 480                 struct discover_boot_option *opt)
 481 {
 482         struct discover_device *dev = opt->device;
 483
 484         if (!dev->notified)
 485                 discover_server_notify_device_add(handler->server,
 486                                                   opt->device->device);
 487         dev->notified = true;
 488         discover_server_notify_boot_option_add(handler->server, opt->option);
 489 }
 490
 491 static void process_boot_option_queue(struct device_handler *handler)
 492 {
 493         struct discover_boot_option *opt, *tmp;
 494
 495         list_for_each_entry_safe(&handler->unresolved_boot_options,
 496                         opt, tmp, list) {
 497
 498                 pb_log("queue: attempting resolution for %s\n",
 499                                 opt->option->id);
 500
 501                 if (!boot_option_resolve(opt, handler))
 502                         continue;
 503
 504                 pb_log("\tresolved!\n");
 505
 506                 list_remove(&opt->list);
 507                 list_add_tail(&opt->device->boot_options, &opt->list);
 508                 talloc_steal(opt->device, opt);
 509                 boot_option_finalise(handler, opt);
 510                 notify_boot_option(handler, opt);
 511         }
 512 }
 513
 514 struct discover_context *device_handler_discover_context_create(
 515                 struct device_handler *handler,
 516                 struct discover_device *device)
 517 {
 518         struct discover_context *ctx;
 519
 520         ctx = talloc(handler, struct discover_context);
 521         ctx->device = device;
 522         ctx->conf_url = NULL;
 523         list_init(&ctx->boot_options);
 524
 525         return ctx;
 526 }
 527
 528 /**
 529  * context_commit - Commit a temporary discovery context to the handler,
 530  * and notify the clients about any new options / devices
 531  */
 532 void device_handler_discover_context_commit(struct device_handler *handler,
 533                 struct discover_context *ctx)
 534 {
 535         struct discover_device *dev = ctx->device;
 536         struct discover_boot_option *opt, *tmp;
 537
 538         if (!device_lookup_by_id(handler, dev->device->id))
 539                 device_handler_add_device(handler, dev);
 540
 541         /* move boot options from the context to the device */
 542         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
 543                 list_remove(&opt->list);
 544
 545                 if (boot_option_resolve(opt, handler)) {
 546                         pb_log("boot option %s is resolved, "
 547                                         "sending to clients\n",
 548                                         opt->option->id);
 549                         list_add_tail(&dev->boot_options, &opt->list);
 550                         talloc_steal(dev, opt);
 551                         boot_option_finalise(handler, opt);
 552                         notify_boot_option(handler, opt);
 553                 } else {
 554                         if (!opt->source->resolve_resource) {
 555                                 pb_log("parser %s gave us an unresolved "
 556                                         "resource (%s), but no way to "
 557                                         "resolve it\n",
 558                                         opt->source->name, opt->option->id);
 559                                 talloc_free(opt);
 560                         } else {
 561                                 pb_log("boot option %s is unresolved, "
 562                                                 "adding to queue\n",
 563                                                 opt->option->id);
 564                                 list_add(&handler->unresolved_boot_options,
 565                                                 &opt->list);
 566                                 talloc_steal(handler, opt);
 567                         }
 568                 }
 569         }
 570 }
 571
 572 void device_handler_add_device(struct device_handler *handler,
 573                 struct discover_device *device)
 574 {
 575         handler->n_devices++;
 576         handler->devices = talloc_realloc(handler, handler->devices,
 577                                 struct discover_device *, handler->n_devices);
 578         handler->devices[handler->n_devices - 1] = device;
 579
 580 }
 581
 582 /* Start discovery on a hotplugged device. The device will be in our devices
 583  * array, but has only just been initialised by the hotplug source.
 584  */
 585 int device_handler_discover(struct device_handler *handler,
 586                 struct discover_device *dev, enum conf_method method)
 587 {
 588         struct discover_context *ctx;
 589
 590         process_boot_option_queue(handler);
 591
 592         /* create our context */
 593         ctx = device_handler_discover_context_create(handler, dev);
 594
 595         mount_device(dev);
 596
 597         /* run the parsers. This will populate the ctx's boot_option list. */
 598         iterate_parsers(ctx, method);
 599
 600         /* add discovered stuff to the handler */
 601         device_handler_discover_context_commit(handler, ctx);
 602
 603         talloc_free(ctx);
 604
 605         return 0;
 606 }
 607
 608 /* incoming conf event */
 609 int device_handler_conf(struct device_handler *handler,
 610                 struct discover_device *dev, struct pb_url *url,
 611                 enum conf_method method)
 612 {
 613         struct discover_context *ctx;
 614
 615         /* create our context */
 616         ctx = device_handler_discover_context_create(handler, dev);
 617         ctx->conf_url = url;
 618
 619         iterate_parsers(ctx, method);
 620
 621         device_handler_discover_context_commit(handler, ctx);
 622
 623         talloc_free(ctx);
 624
 625         return 0;
 626 }
 627
 628 static struct discover_boot_option *find_boot_option_by_id(
 629                 struct device_handler *handler, const char *id)
 630 {
 631         unsigned int i;
 632
 633         for (i = 0; i < handler->n_devices; i++) {
 634                 struct discover_device *dev = handler->devices[i];
 635                 struct discover_boot_option *opt;
 636
 637                 list_for_each_entry(&dev->boot_options, opt, list)
 638                         if (!strcmp(opt->option->id, id))
 639                                 return opt;
 640         }
 641
 642         return NULL;
 643 }
 644
 645 void device_handler_boot(struct device_handler *handler,
 646                 struct boot_command *cmd)
 647 {
 648         struct discover_boot_option *opt;
 649
 650         opt = find_boot_option_by_id(handler, cmd->option_id);
 651
 652         boot(handler, opt, cmd, handler->dry_run, boot_status, handler);
 653 }
 654
 655 void device_handler_cancel_default(struct device_handler *handler)
 656 {
 657         struct boot_status status;
 658
 659         if (handler->timeout_waiter)
 660                 waiter_remove(handler->timeout_waiter);
 661
 662         handler->timeout_waiter = NULL;
 663         handler->autoboot_enabled = false;
 664
 665         /* we only send status if we had a default boot option queued */
 666         if (!handler->default_boot_option)
 667                 return;
 668
 669         pb_log("Cancelling default boot option\n");
 670
 671         handler->default_boot_option = NULL;
 672
 673         status.type = BOOT_STATUS_INFO;
 674         status.progress = -1;
 675         status.detail = NULL;
 676         status.message = "Default boot cancelled";
 677
 678         discover_server_notify_boot_status(handler->server, &status);
 679 }
 680
 681 #ifndef PETITBOOT_TEST
 682 static bool check_existing_mount(struct discover_device *dev)
 683 {
 684         struct stat devstat, mntstat;
 685         struct mntent *mnt;
 686         FILE *fp;
 687         int rc;
 688
 689         rc = stat(dev->device_path, &devstat);
 690         if (rc) {
 691                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
 692                 return false;
 693         }
 694
 695         if (!S_ISBLK(devstat.st_mode)) {
 696                 pb_debug("%s: %s isn't a block device?\n", __func__,
 697                                 dev->device_path);
 698                 return false;
 699         }
 700
 701         fp = fopen("/proc/self/mounts", "r");
 702
 703         for (;;) {
 704                 mnt = getmntent(fp);
 705                 if (!mnt)
 706                         break;
 707
 708                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
 709                         continue;
 710
 711                 rc = stat(mnt->mnt_fsname, &mntstat);
 712                 if (rc)
 713                         continue;
 714
 715                 if (!S_ISBLK(mntstat.st_mode))
 716                         continue;
 717
 718                 if (mntstat.st_rdev == devstat.st_rdev) {
 719                         pb_debug("%s: %s is already mounted at %s\n"
 720                                         __func__, dev->device_path,
 721                                         mnt->mnt_dir);
 722                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
 723                         dev->mounted = true;
 724                         dev->unmount = false;
 725                         break;
 726                 }
 727         }
 728
 729         fclose(fp);
 730
 731         return mnt != NULL;
 732 }
 733
 734 static int mount_device(struct discover_device *dev)
 735 {
 736         int rc;
 737
 738         if (!dev->device_path)
 739                 return -1;
 740
 741         if (dev->mounted)
 742                 return 0;
 743
 744         if (check_existing_mount(dev))
 745                 return 0;
 746
 747         dev->mount_path = join_paths(dev, mount_base(),
 748                                         dev->device_path);
 749
 750         if (pb_mkdir_recursive(dev->mount_path)) {
 751                 pb_log("couldn't create mount directory %s: %s\n",
 752                                 dev->mount_path, strerror(errno));
 753                 goto err_free;
 754         }
 755
 756         rc = process_run_simple(dev, pb_system_apps.mount,
 757                         dev->device_path, dev->mount_path,
 758                         "-o", "ro", NULL);
 759         if (!rc) {
 760                 dev->mounted = true;
 761                 dev->unmount = true;
 762                 return 0;
 763         }
 764
 765         /* Retry mount without ro option. */
 766         rc = process_run_simple(dev, pb_system_apps.mount,
 767                         dev->device_path, dev->mount_path, NULL);
 768
 769         if (!rc) {
 770                 dev->mounted = true;
 771                 dev->unmount = true;
 772                 return 0;
 773         }
 774
 775         pb_rmdir_recursive(mount_base(), dev->mount_path);
 776 err_free:
 777         talloc_free(dev->mount_path);
 778         dev->mount_path = NULL;
 779         return -1;
 780 }
 781
 782 static int umount_device(struct discover_device *dev)
 783 {
 784         int status;
 785
 786         if (!dev->mounted || !dev->unmount)
 787                 return 0;
 788
 789         status = process_run_simple(dev, pb_system_apps.umount,
 790                         dev->mount_path, NULL);
 791
 792         if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
 793                 return -1;
 794
 795         dev->mounted = false;
 796         talloc_free(dev->mount_path);
 797         dev->mount_path = NULL;
 798
 799         pb_rmdir_recursive(mount_base(), dev->mount_path);
 800
 801         return 0;
 802 }
 803 #else
 804
 805 static int umount_device(struct discover_device *dev __attribute__((unused)))
 806 {
 807         return 0;
 808 }
 809
 810 static int __attribute__((unused)) mount_device(
 811                 struct discover_device *dev __attribute__((unused)))
 812 {
 813         return 0;
 814 }
 815
 816 #endif
 817