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

   1 #include <assert.h>
   2 #include <stdlib.h>
   3 #include <stdbool.h>
   4 #include <unistd.h>
   5 #include <string.h>
   6 #include <errno.h>
   7 #include <mntent.h>
   8 #include <sys/stat.h>
   9 #include <sys/wait.h>
  10 #include <sys/mount.h>
  11
  12 #include <talloc/talloc.h>
  13 #include <list/list.h>
  14 #include <log/log.h>
  15 #include <types/types.h>
  16 #include <system/system.h>
  17 #include <process/process.h>
  18 #include <url/url.h>
  19
  20 #include "device-handler.h"
  21 #include "discover-server.h"
  22 #include "platform.h"
  23 #include "event.h"
  24 #include "parser.h"
  25 #include "resource.h"
  26 #include "paths.h"
  27 #include "sysinfo.h"
  28 #include "boot.h"
  29
  30 struct device_handler {
  31         struct discover_server  *server;
  32         int                     dry_run;
  33
  34         struct discover_device  **devices;
  35         unsigned int            n_devices;
  36
  37         struct waitset          *waitset;
  38         struct waiter           *timeout_waiter;
  39         bool                    autoboot_enabled;
  40         unsigned int            sec_to_boot;
  41
  42         struct discover_boot_option *default_boot_option;
  43         struct list             unresolved_boot_options;
  44
  45         struct boot_task        *pending_boot;
  46         bool                    pending_boot_is_default;
  47 };
  48
  49 static int mount_device(struct discover_device *dev);
  50 static int umount_device(struct discover_device *dev);
  51
  52 void discover_context_add_boot_option(struct discover_context *ctx,
  53                 struct discover_boot_option *boot_option)
  54 {
  55         boot_option->source = ctx->parser;
  56         list_add_tail(&ctx->boot_options, &boot_option->list);
  57         talloc_steal(ctx, boot_option);
  58 }
  59
  60 /**
  61  * device_handler_get_device_count - Get the count of current handler devices.
  62  */
  63
  64 int device_handler_get_device_count(const struct device_handler *handler)
  65 {
  66         return handler->n_devices;
  67 }
  68
  69 /**
  70  * device_handler_get_device - Get a handler device by index.
  71  */
  72
  73 const struct discover_device *device_handler_get_device(
  74         const struct device_handler *handler, unsigned int index)
  75 {
  76         if (index >= handler->n_devices) {
  77                 assert(0 && "bad index");
  78                 return NULL;
  79         }
  80
  81         return handler->devices[index];
  82 }
  83
  84 struct discover_boot_option *discover_boot_option_create(
  85                 struct discover_context *ctx,
  86                 struct discover_device *device)
  87 {
  88         struct discover_boot_option *opt;
  89
  90         opt = talloc_zero(ctx, struct discover_boot_option);
  91         opt->option = talloc_zero(opt, struct boot_option);
  92         opt->device = device;
  93
  94         return opt;
  95 }
  96
  97 static int device_match_uuid(struct discover_device *dev, const char *uuid)
  98 {
  99         return dev->uuid && !strcmp(dev->uuid, uuid);
 100 }
 101
 102 static int device_match_label(struct discover_device *dev, const char *label)
 103 {
 104         return dev->label && !strcmp(dev->label, label);
 105 }
 106
 107 static int device_match_id(struct discover_device *dev, const char *id)
 108 {
 109         return !strcmp(dev->device->id, id);
 110 }
 111
 112 static int device_match_serial(struct discover_device *dev, const char *serial)
 113 {
 114         const char *val = discover_device_get_param(dev, "ID_SERIAL");
 115         return val && !strcmp(val, serial);
 116 }
 117
 118 static struct discover_device *device_lookup(
 119                 struct device_handler *device_handler,
 120                 int (match_fn)(struct discover_device *, const char *),
 121                 const char *str)
 122 {
 123         struct discover_device *dev;
 124         unsigned int i;
 125
 126         if (!str)
 127                 return NULL;
 128
 129         for (i = 0; i < device_handler->n_devices; i++) {
 130                 dev = device_handler->devices[i];
 131
 132                 if (match_fn(dev, str))
 133                         return dev;
 134         }
 135
 136         return NULL;
 137 }
 138
 139 struct discover_device *device_lookup_by_name(struct device_handler *handler,
 140                 const char *name)
 141 {
 142         if (!strncmp(name, "/dev/", strlen("/dev/")))
 143                 name += strlen("/dev/");
 144
 145         return device_lookup_by_id(handler, name);
 146 }
 147
 148 struct discover_device *device_lookup_by_uuid(
 149                 struct device_handler *device_handler,
 150                 const char *uuid)
 151 {
 152         return device_lookup(device_handler, device_match_uuid, uuid);
 153 }
 154
 155 struct discover_device *device_lookup_by_label(
 156                 struct device_handler *device_handler,
 157                 const char *label)
 158 {
 159         return device_lookup(device_handler, device_match_label, label);
 160 }
 161
 162 struct discover_device *device_lookup_by_id(
 163                 struct device_handler *device_handler,
 164                 const char *id)
 165 {
 166         return device_lookup(device_handler, device_match_id, id);
 167 }
 168
 169 struct discover_device *device_lookup_by_serial(
 170                 struct device_handler *device_handler,
 171                 const char *serial)
 172 {
 173         return device_lookup(device_handler, device_match_serial, serial);
 174 }
 175
 176 void device_handler_destroy(struct device_handler *handler)
 177 {
 178         talloc_free(handler);
 179 }
 180
 181 static int destroy_device(void *arg)
 182 {
 183         struct discover_device *dev = arg;
 184
 185         umount_device(dev);
 186
 187         return 0;
 188 }
 189
 190 struct discover_device *discover_device_create(struct device_handler *handler,
 191                 const char *id)
 192 {
 193         struct discover_device *dev;
 194
 195         dev = device_lookup_by_id(handler, id);
 196         if (dev)
 197                 return dev;
 198
 199         dev = talloc_zero(handler, struct discover_device);
 200         dev->device = talloc_zero(dev, struct device);
 201         dev->device->id = talloc_strdup(dev->device, id);
 202         list_init(&dev->params);
 203         list_init(&dev->boot_options);
 204
 205         talloc_set_destructor(dev, destroy_device);
 206
 207         return dev;
 208 }
 209
 210 struct discover_device_param {
 211         char                    *name;
 212         char                    *value;
 213         struct list_item        list;
 214 };
 215
 216 void discover_device_set_param(struct discover_device *device,
 217                 const char *name, const char *value)
 218 {
 219         struct discover_device_param *param;
 220         bool found = false;
 221
 222         list_for_each_entry(&device->params, param, list) {
 223                 if (!strcmp(param->name, name)) {
 224                         found = true;
 225                         break;
 226                 }
 227         }
 228
 229         if (!found) {
 230                 if (!value)
 231                         return;
 232                 param = talloc(device, struct discover_device_param);
 233                 param->name = talloc_strdup(param, name);
 234                 list_add(&device->params, &param->list);
 235         } else {
 236                 if (!value) {
 237                         list_remove(&param->list);
 238                         talloc_free(param);
 239                         return;
 240                 }
 241                 talloc_free(param->value);
 242         }
 243
 244         param->value = talloc_strdup(param, value);
 245 }
 246
 247 const char *discover_device_get_param(struct discover_device *device,
 248                 const char *name)
 249 {
 250         struct discover_device_param *param;
 251
 252         list_for_each_entry(&device->params, param, list) {
 253                 if (!strcmp(param->name, name))
 254                         return param->value;
 255         }
 256         return NULL;
 257 }
 258
 259 struct device_handler *device_handler_init(struct discover_server *server,
 260                 struct waitset *waitset, int dry_run)
 261 {
 262         struct device_handler *handler;
 263
 264         handler = talloc_zero(NULL, struct device_handler);
 265         handler->server = server;
 266         handler->waitset = waitset;
 267         handler->dry_run = dry_run;
 268         handler->autoboot_enabled = config_get()->autoboot_enabled;
 269
 270         list_init(&handler->unresolved_boot_options);
 271
 272         /* set up our mount point base */
 273         pb_mkdir_recursive(mount_base());
 274
 275         parser_init();
 276
 277         return handler;
 278 }
 279
 280 void device_handler_remove(struct device_handler *handler,
 281                 struct discover_device *device)
 282 {
 283         struct discover_boot_option *opt, *tmp;
 284         unsigned int i;
 285
 286         for (i = 0; i < handler->n_devices; i++)
 287                 if (handler->devices[i] == device)
 288                         break;
 289
 290         if (i == handler->n_devices) {
 291                 talloc_free(device);
 292                 return;
 293         }
 294
 295         /* Free any unresolved options, as they're currently allocated
 296          * against the handler */
 297         list_for_each_entry_safe(&handler->unresolved_boot_options,
 298                         opt, tmp, list) {
 299                 if (opt->device != device)
 300                         continue;
 301                 list_remove(&opt->list);
 302                 talloc_free(opt);
 303         }
 304
 305         handler->n_devices--;
 306         memmove(&handler->devices[i], &handler->devices[i + 1],
 307                 (handler->n_devices - i) * sizeof(handler->devices[0]));
 308         handler->devices = talloc_realloc(handler, handler->devices,
 309                 struct discover_device *, handler->n_devices);
 310
 311         if (device->notified)
 312                 discover_server_notify_device_remove(handler->server,
 313                                                         device->device);
 314
 315         talloc_free(device);
 316 }
 317
 318 static void boot_status(void *arg, struct boot_status *status)
 319 {
 320         struct device_handler *handler = arg;
 321
 322         discover_server_notify_boot_status(handler->server, status);
 323 }
 324
 325 static void countdown_status(struct device_handler *handler,
 326                 struct discover_boot_option *opt, unsigned int sec)
 327 {
 328         struct boot_status status;
 329
 330         status.type = BOOT_STATUS_INFO;
 331         status.progress = -1;
 332         status.detail = NULL;
 333         status.message = talloc_asprintf(handler,
 334                         "Booting %s in %u sec", opt->option->name, sec);
 335
 336         discover_server_notify_boot_status(handler->server, &status);
 337
 338         talloc_free(status.message);
 339 }
 340
 341 static int default_timeout(void *arg)
 342 {
 343         struct device_handler *handler = arg;
 344         struct discover_boot_option *opt;
 345
 346         if (!handler->default_boot_option)
 347                 return 0;
 348
 349         if (handler->pending_boot)
 350                 return 0;
 351
 352         opt = handler->default_boot_option;
 353
 354         if (handler->sec_to_boot) {
 355                 countdown_status(handler, opt, handler->sec_to_boot);
 356                 handler->sec_to_boot--;
 357                 handler->timeout_waiter = waiter_register_timeout(
 358                                                 handler->waitset, 1000,
 359                                                 default_timeout, handler);
 360                 return 0;
 361         }
 362
 363         handler->timeout_waiter = NULL;
 364
 365         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 366
 367         handler->pending_boot = boot(handler, handler->default_boot_option,
 368                         NULL, handler->dry_run, boot_status, handler);
 369         handler->pending_boot_is_default = true;
 370         return 0;
 371 }
 372
 373 static bool priority_match(struct boot_priority *prio,
 374                 struct discover_boot_option *opt)
 375 {
 376         return prio->type == opt->device->device->type ||
 377                 prio->type == DEVICE_TYPE_ANY;
 378 }
 379
 380 static int default_option_priority(struct discover_boot_option *opt)
 381 {
 382         const struct config *config;
 383         struct boot_priority *prio;
 384         unsigned int i;
 385
 386         config = config_get();
 387
 388         for (i = 0; i < config->n_boot_priorities; i++) {
 389                 prio = &config->boot_priorities[i];
 390                 if (priority_match(prio, opt))
 391                         return prio->priority;
 392         }
 393
 394         return 0;
 395 }
 396
 397 static void set_default(struct device_handler *handler,
 398                 struct discover_boot_option *opt)
 399 {
 400         int new_prio;
 401
 402         if (!handler->autoboot_enabled)
 403                 return;
 404
 405         new_prio = default_option_priority(opt);
 406
 407         /* A negative priority indicates that we don't want to boot this device
 408          * by default */
 409         if (new_prio < 0)
 410                 return;
 411
 412         /* Resolve any conflicts: if we have a new default option, it only
 413          * replaces the current if it has a higher priority. */
 414         if (handler->default_boot_option) {
 415                 int cur_prio;
 416
 417                 cur_prio = default_option_priority(
 418                                         handler->default_boot_option);
 419
 420                 if (new_prio > cur_prio) {
 421                         handler->default_boot_option = opt;
 422                         /* extend the timeout a little, so the user sees some
 423                          * indication of the change */
 424                         handler->sec_to_boot += 2;
 425                 }
 426
 427                 return;
 428         }
 429
 430         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
 431         handler->default_boot_option = opt;
 432
 433         pb_log("Boot option %s set as default, timeout %u sec.\n",
 434                opt->option->id, handler->sec_to_boot);
 435
 436         default_timeout(handler);
 437 }
 438
 439 static bool resource_is_resolved(struct resource *res)
 440 {
 441         return !res || res->resolved;
 442 }
 443
 444 /* We only use this in an assert, which will disappear if we're compiling
 445  * with NDEBUG, so we need the 'used' attribute for these builds */
 446 static bool __attribute__((used)) boot_option_is_resolved(
 447                 struct discover_boot_option *opt)
 448 {
 449         return resource_is_resolved(opt->boot_image) &&
 450                 resource_is_resolved(opt->initrd) &&
 451                 resource_is_resolved(opt->dtb) &&
 452                 resource_is_resolved(opt->icon);
 453 }
 454
 455 static bool resource_resolve(struct resource *res, const char *name,
 456                 struct discover_boot_option *opt,
 457                 struct device_handler *handler)
 458 {
 459         struct parser *parser = opt->source;
 460
 461         if (resource_is_resolved(res))
 462                 return true;
 463
 464         pb_debug("Attempting to resolve resource %s->%s with parser %s\n",
 465                         opt->option->id, name, parser->name);
 466         parser->resolve_resource(handler, res);
 467
 468         return res->resolved;
 469 }
 470
 471 static bool boot_option_resolve(struct discover_boot_option *opt,
 472                 struct device_handler *handler)
 473 {
 474         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
 475                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
 476                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
 477                 resource_resolve(opt->icon, "icon", opt, handler);
 478 }
 479
 480 static void boot_option_finalise(struct device_handler *handler,
 481                 struct discover_boot_option *opt)
 482 {
 483         assert(boot_option_is_resolved(opt));
 484
 485         /* check that the parsers haven't set any of the final data */
 486         assert(!opt->option->boot_image_file);
 487         assert(!opt->option->initrd_file);
 488         assert(!opt->option->dtb_file);
 489         assert(!opt->option->icon_file);
 490         assert(!opt->option->device_id);
 491
 492         if (opt->boot_image)
 493                 opt->option->boot_image_file = opt->boot_image->url->full;
 494         if (opt->initrd)
 495                 opt->option->initrd_file = opt->initrd->url->full;
 496         if (opt->dtb)
 497                 opt->option->dtb_file = opt->dtb->url->full;
 498         if (opt->icon)
 499                 opt->option->icon_file = opt->icon->url->full;
 500
 501         opt->option->device_id = opt->device->device->id;
 502
 503         if (opt->option->is_default)
 504                 set_default(handler, opt);
 505 }
 506
 507 static void notify_boot_option(struct device_handler *handler,
 508                 struct discover_boot_option *opt)
 509 {
 510         struct discover_device *dev = opt->device;
 511
 512         if (!dev->notified)
 513                 discover_server_notify_device_add(handler->server,
 514                                                   opt->device->device);
 515         dev->notified = true;
 516         discover_server_notify_boot_option_add(handler->server, opt->option);
 517 }
 518
 519 static void process_boot_option_queue(struct device_handler *handler)
 520 {
 521         struct discover_boot_option *opt, *tmp;
 522
 523         list_for_each_entry_safe(&handler->unresolved_boot_options,
 524                         opt, tmp, list) {
 525
 526                 pb_debug("queue: attempting resolution for %s\n",
 527                                 opt->option->id);
 528
 529                 if (!boot_option_resolve(opt, handler))
 530                         continue;
 531
 532                 pb_debug("\tresolved!\n");
 533
 534                 list_remove(&opt->list);
 535                 list_add_tail(&opt->device->boot_options, &opt->list);
 536                 talloc_steal(opt->device, opt);
 537                 boot_option_finalise(handler, opt);
 538                 notify_boot_option(handler, opt);
 539         }
 540 }
 541
 542 struct discover_context *device_handler_discover_context_create(
 543                 struct device_handler *handler,
 544                 struct discover_device *device)
 545 {
 546         struct discover_context *ctx;
 547
 548         ctx = talloc_zero(handler, struct discover_context);
 549         ctx->device = device;
 550         list_init(&ctx->boot_options);
 551
 552         return ctx;
 553 }
 554
 555 /**
 556  * context_commit - Commit a temporary discovery context to the handler,
 557  * and notify the clients about any new options / devices
 558  */
 559 void device_handler_discover_context_commit(struct device_handler *handler,
 560                 struct discover_context *ctx)
 561 {
 562         struct discover_device *dev = ctx->device;
 563         struct discover_boot_option *opt, *tmp;
 564
 565         if (!device_lookup_by_id(handler, dev->device->id))
 566                 device_handler_add_device(handler, dev);
 567
 568         /* move boot options from the context to the device */
 569         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
 570                 list_remove(&opt->list);
 571
 572                 if (boot_option_resolve(opt, handler)) {
 573                         pb_log("boot option %s is resolved, "
 574                                         "sending to clients\n",
 575                                         opt->option->id);
 576                         list_add_tail(&dev->boot_options, &opt->list);
 577                         talloc_steal(dev, opt);
 578                         boot_option_finalise(handler, opt);
 579                         notify_boot_option(handler, opt);
 580                 } else {
 581                         if (!opt->source->resolve_resource) {
 582                                 pb_log("parser %s gave us an unresolved "
 583                                         "resource (%s), but no way to "
 584                                         "resolve it\n",
 585                                         opt->source->name, opt->option->id);
 586                                 talloc_free(opt);
 587                         } else {
 588                                 pb_log("boot option %s is unresolved, "
 589                                                 "adding to queue\n",
 590                                                 opt->option->id);
 591                                 list_add(&handler->unresolved_boot_options,
 592                                                 &opt->list);
 593                                 talloc_steal(handler, opt);
 594                         }
 595                 }
 596         }
 597 }
 598
 599 void device_handler_add_device(struct device_handler *handler,
 600                 struct discover_device *device)
 601 {
 602         handler->n_devices++;
 603         handler->devices = talloc_realloc(handler, handler->devices,
 604                                 struct discover_device *, handler->n_devices);
 605         handler->devices[handler->n_devices - 1] = device;
 606
 607 }
 608
 609 /* Start discovery on a hotplugged device. The device will be in our devices
 610  * array, but has only just been initialised by the hotplug source.
 611  */
 612 int device_handler_discover(struct device_handler *handler,
 613                 struct discover_device *dev)
 614 {
 615         struct discover_context *ctx;
 616         int rc;
 617
 618         process_boot_option_queue(handler);
 619
 620         /* create our context */
 621         ctx = device_handler_discover_context_create(handler, dev);
 622
 623         rc = mount_device(dev);
 624         if (rc)
 625                 goto out;
 626
 627         /* add this device to our system info */
 628         system_info_register_blockdev(dev->device->id, dev->uuid,
 629                         dev->mount_path);
 630
 631         /* run the parsers. This will populate the ctx's boot_option list. */
 632         iterate_parsers(ctx);
 633
 634         /* add discovered stuff to the handler */
 635         device_handler_discover_context_commit(handler, ctx);
 636
 637 out:
 638         talloc_free(ctx);
 639
 640         return 0;
 641 }
 642
 643 /* Incoming dhcp event */
 644 int device_handler_dhcp(struct device_handler *handler,
 645                 struct discover_device *dev, struct event *event)
 646 {
 647         struct discover_context *ctx;
 648
 649         /* create our context */
 650         ctx = device_handler_discover_context_create(handler, dev);
 651         ctx->event = event;
 652
 653         iterate_parsers(ctx);
 654
 655         device_handler_discover_context_commit(handler, ctx);
 656
 657         talloc_free(ctx);
 658
 659         return 0;
 660 }
 661
 662 /* incoming conf event */
 663 int device_handler_conf(struct device_handler *handler,
 664                 struct discover_device *dev, struct pb_url *url)
 665 {
 666         struct discover_context *ctx;
 667
 668         /* create our context */
 669         ctx = device_handler_discover_context_create(handler, dev);
 670         ctx->conf_url = url;
 671
 672         iterate_parsers(ctx);
 673
 674         device_handler_discover_context_commit(handler, ctx);
 675
 676         talloc_free(ctx);
 677
 678         return 0;
 679 }
 680
 681 static struct discover_boot_option *find_boot_option_by_id(
 682                 struct device_handler *handler, const char *id)
 683 {
 684         unsigned int i;
 685
 686         for (i = 0; i < handler->n_devices; i++) {
 687                 struct discover_device *dev = handler->devices[i];
 688                 struct discover_boot_option *opt;
 689
 690                 list_for_each_entry(&dev->boot_options, opt, list)
 691                         if (!strcmp(opt->option->id, id))
 692                                 return opt;
 693         }
 694
 695         return NULL;
 696 }
 697
 698 void device_handler_boot(struct device_handler *handler,
 699                 struct boot_command *cmd)
 700 {
 701         struct discover_boot_option *opt = NULL;
 702
 703         if (cmd->option_id && strlen(cmd->option_id))
 704                 opt = find_boot_option_by_id(handler, cmd->option_id);
 705
 706         if (handler->pending_boot)
 707                 boot_cancel(handler->pending_boot);
 708         handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
 709                         boot_status, handler);
 710         handler->pending_boot_is_default = false;
 711 }
 712
 713 void device_handler_cancel_default(struct device_handler *handler)
 714 {
 715         struct boot_status status;
 716
 717         if (handler->timeout_waiter)
 718                 waiter_remove(handler->timeout_waiter);
 719
 720         handler->timeout_waiter = NULL;
 721         handler->autoboot_enabled = false;
 722
 723         /* we only send status if we had a default boot option queued */
 724         if (!handler->default_boot_option)
 725                 return;
 726
 727         pb_log("Cancelling default boot option\n");
 728
 729         if (handler->pending_boot && handler->pending_boot_is_default) {
 730                 boot_cancel(handler->pending_boot);
 731                 handler->pending_boot = NULL;
 732                 handler->pending_boot_is_default = false;
 733         }
 734
 735         handler->default_boot_option = NULL;
 736
 737         status.type = BOOT_STATUS_INFO;
 738         status.progress = -1;
 739         status.detail = NULL;
 740         status.message = "Default boot cancelled";
 741
 742         discover_server_notify_boot_status(handler->server, &status);
 743 }
 744
 745 void device_handler_update_config(struct device_handler *handler,
 746                 struct config *config)
 747 {
 748         config_set(config);
 749         discover_server_notify_config(handler->server, config);
 750 }
 751
 752 #ifndef PETITBOOT_TEST
 753 static bool check_existing_mount(struct discover_device *dev)
 754 {
 755         struct stat devstat, mntstat;
 756         struct mntent *mnt;
 757         FILE *fp;
 758         int rc;
 759
 760         rc = stat(dev->device_path, &devstat);
 761         if (rc) {
 762                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
 763                 return false;
 764         }
 765
 766         if (!S_ISBLK(devstat.st_mode)) {
 767                 pb_debug("%s: %s isn't a block device?\n", __func__,
 768                                 dev->device_path);
 769                 return false;
 770         }
 771
 772         fp = fopen("/proc/self/mounts", "r");
 773
 774         for (;;) {
 775                 mnt = getmntent(fp);
 776                 if (!mnt)
 777                         break;
 778
 779                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
 780                         continue;
 781
 782                 rc = stat(mnt->mnt_fsname, &mntstat);
 783                 if (rc)
 784                         continue;
 785
 786                 if (!S_ISBLK(mntstat.st_mode))
 787                         continue;
 788
 789                 if (mntstat.st_rdev == devstat.st_rdev) {
 790                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
 791                         dev->mounted_rw = !!hasmntopt(mnt, "rw");
 792                         dev->mounted = true;
 793                         dev->unmount = false;
 794
 795                         pb_debug("%s: %s is already mounted (r%c) at %s\n",
 796                                         __func__, dev->device_path,
 797                                         dev->mounted_rw ? 'w' : 'o',
 798                                         mnt->mnt_dir);
 799                         break;
 800                 }
 801         }
 802
 803         fclose(fp);
 804
 805         return mnt != NULL;
 806 }
 807
 808 static int mount_device(struct discover_device *dev)
 809 {
 810         const char *fstype;
 811         int rc;
 812
 813         if (!dev->device_path)
 814                 return -1;
 815
 816         if (dev->mounted)
 817                 return 0;
 818
 819         if (check_existing_mount(dev))
 820                 return 0;
 821
 822         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
 823         if (!fstype)
 824                 return 0;
 825
 826         dev->mount_path = join_paths(dev, mount_base(),
 827                                         dev->device_path);
 828
 829         if (pb_mkdir_recursive(dev->mount_path)) {
 830                 pb_log("couldn't create mount directory %s: %s\n",
 831                                 dev->mount_path, strerror(errno));
 832                 goto err_free;
 833         }
 834
 835         pb_log("mounting device %s read-only\n", dev->device_path);
 836         errno = 0;
 837         rc = mount(dev->device_path, dev->mount_path, fstype,
 838                         MS_RDONLY | MS_SILENT, "");
 839         if (!rc) {
 840                 dev->mounted = true;
 841                 dev->mounted_rw = false;
 842                 dev->unmount = true;
 843                 return 0;
 844         }
 845
 846         pb_log("couldn't mount device %s: mount failed: %s\n",
 847                         dev->device_path, strerror(errno));
 848
 849         pb_rmdir_recursive(mount_base(), dev->mount_path);
 850 err_free:
 851         talloc_free(dev->mount_path);
 852         dev->mount_path = NULL;
 853         return -1;
 854 }
 855
 856 static int umount_device(struct discover_device *dev)
 857 {
 858         int rc;
 859
 860         if (!dev->mounted || !dev->unmount)
 861                 return 0;
 862
 863         pb_log("unmounting device %s\n", dev->device_path);
 864         rc = umount(dev->mount_path);
 865         if (rc)
 866                 return -1;
 867
 868         dev->mounted = false;
 869
 870         pb_rmdir_recursive(mount_base(), dev->mount_path);
 871
 872         talloc_free(dev->mount_path);
 873         dev->mount_path = NULL;
 874
 875         return 0;
 876 }
 877
 878 int device_request_write(struct discover_device *dev, bool *release)
 879 {
 880         int rc;
 881
 882         *release = false;
 883
 884         if (!dev->mounted)
 885                 return -1;
 886
 887         if (dev->mounted_rw)
 888                 return 0;
 889
 890         pb_log("remounting device %s read-write\n", dev->device_path);
 891         rc = mount(dev->device_path, dev->mount_path, "",
 892                         MS_REMOUNT | MS_SILENT, "");
 893         if (rc)
 894                 return -1;
 895
 896         dev->mounted_rw = true;
 897         *release = true;
 898         return 0;
 899 }
 900
 901 void device_release_write(struct discover_device *dev, bool release)
 902 {
 903         if (!release)
 904                 return;
 905
 906         pb_log("remounting device %s read-only\n", dev->device_path);
 907         mount(dev->device_path, dev->mount_path, "",
 908                         MS_REMOUNT | MS_RDONLY | MS_SILENT, "");
 909         dev->mounted_rw = false;
 910 }
 911
 912 #else
 913
 914 static int umount_device(struct discover_device *dev __attribute__((unused)))
 915 {
 916         return 0;
 917 }
 918
 919 static int __attribute__((unused)) mount_device(
 920                 struct discover_device *dev __attribute__((unused)))
 921 {
 922         return 0;
 923 }
 924
 925 int device_request_write(struct discover_device *dev __attribute__((unused)),
 926                 bool *release)
 927 {
 928         *release = true;
 929         return 0;
 930 }
 931
 932 void device_release_write(struct discover_device *dev __attribute__((unused)),
 933         bool release __attribute__((unused)))
 934 {
 935 }
 936
 937 #endif
 938