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 <locale.h>
   9 #include <sys/stat.h>
  10 #include <sys/wait.h>
  11 #include <sys/mount.h>
  12
  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 #include <i18n/i18n.h>
  21
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24 #include <netdb.h>
  25 #include <arpa/inet.h>
  26
  27 #include "device-handler.h"
  28 #include "discover-server.h"
  29 #include "devmapper.h"
  30 #include "user-event.h"
  31 #include "platform.h"
  32 #include "event.h"
  33 #include "parser.h"
  34 #include "resource.h"
  35 #include "paths.h"
  36 #include "sysinfo.h"
  37 #include "boot.h"
  38 #include "udev.h"
  39 #include "network.h"
  40 #include "ipmi.h"
  41
  42 enum default_priority {
  43         DEFAULT_PRIORITY_REMOTE         = 1,
  44         DEFAULT_PRIORITY_LOCAL_FIRST    = 2,
  45         DEFAULT_PRIORITY_LOCAL_LAST     = 0xfe,
  46         DEFAULT_PRIORITY_DISABLED       = 0xff,
  47 };
  48
  49 struct device_handler {
  50         struct discover_server  *server;
  51         int                     dry_run;
  52
  53         struct pb_udev          *udev;
  54         struct network          *network;
  55         struct user_event       *user_event;
  56
  57         struct discover_device  **devices;
  58         unsigned int            n_devices;
  59
  60         struct ramdisk_device   **ramdisks;
  61         unsigned int            n_ramdisks;
  62
  63         struct waitset          *waitset;
  64         struct waiter           *timeout_waiter;
  65         bool                    autoboot_enabled;
  66         unsigned int            sec_to_boot;
  67
  68         struct discover_boot_option *default_boot_option;
  69         int                     default_boot_option_priority;
  70
  71         struct list             unresolved_boot_options;
  72
  73         struct boot_task        *pending_boot;
  74         bool                    pending_boot_is_default;
  75 };
  76
  77 static int mount_device(struct discover_device *dev);
  78 static int umount_device(struct discover_device *dev);
  79
  80 static int device_handler_init_sources(struct device_handler *handler);
  81 static void device_handler_reinit_sources(struct device_handler *handler);
  82
  83 static void device_handler_update_lang(const char *lang);
  84
  85 void discover_context_add_boot_option(struct discover_context *ctx,
  86                 struct discover_boot_option *boot_option)
  87 {
  88         boot_option->source = ctx->parser;
  89         list_add_tail(&ctx->boot_options, &boot_option->list);
  90         talloc_steal(ctx, boot_option);
  91 }
  92
  93 /**
  94  * device_handler_get_device_count - Get the count of current handler devices.
  95  */
  96
  97 int device_handler_get_device_count(const struct device_handler *handler)
  98 {
  99         return handler->n_devices;
 100 }
 101
 102 /**
 103  * device_handler_get_device - Get a handler device by index.
 104  */
 105
 106 const struct discover_device *device_handler_get_device(
 107         const struct device_handler *handler, unsigned int index)
 108 {
 109         if (index >= handler->n_devices) {
 110                 assert(0 && "bad index");
 111                 return NULL;
 112         }
 113
 114         return handler->devices[index];
 115 }
 116
 117 struct discover_boot_option *discover_boot_option_create(
 118                 struct discover_context *ctx,
 119                 struct discover_device *device)
 120 {
 121         struct discover_boot_option *opt;
 122
 123         opt = talloc_zero(ctx, struct discover_boot_option);
 124         opt->option = talloc_zero(opt, struct boot_option);
 125         opt->device = device;
 126
 127         return opt;
 128 }
 129
 130 static int device_match_uuid(struct discover_device *dev, const char *uuid)
 131 {
 132         return dev->uuid && !strcmp(dev->uuid, uuid);
 133 }
 134
 135 static int device_match_label(struct discover_device *dev, const char *label)
 136 {
 137         return dev->label && !strcmp(dev->label, label);
 138 }
 139
 140 static int device_match_id(struct discover_device *dev, const char *id)
 141 {
 142         return !strcmp(dev->device->id, id);
 143 }
 144
 145 static int device_match_serial(struct discover_device *dev, const char *serial)
 146 {
 147         const char *val = discover_device_get_param(dev, "ID_SERIAL");
 148         return val && !strcmp(val, serial);
 149 }
 150
 151 static struct discover_device *device_lookup(
 152                 struct device_handler *device_handler,
 153                 int (match_fn)(struct discover_device *, const char *),
 154                 const char *str)
 155 {
 156         struct discover_device *dev;
 157         unsigned int i;
 158
 159         if (!str)
 160                 return NULL;
 161
 162         for (i = 0; i < device_handler->n_devices; i++) {
 163                 dev = device_handler->devices[i];
 164
 165                 if (match_fn(dev, str))
 166                         return dev;
 167         }
 168
 169         return NULL;
 170 }
 171
 172 struct discover_device *device_lookup_by_name(struct device_handler *handler,
 173                 const char *name)
 174 {
 175         if (!strncmp(name, "/dev/", strlen("/dev/")))
 176                 name += strlen("/dev/");
 177
 178         return device_lookup_by_id(handler, name);
 179 }
 180
 181 struct discover_device *device_lookup_by_uuid(
 182                 struct device_handler *device_handler,
 183                 const char *uuid)
 184 {
 185         return device_lookup(device_handler, device_match_uuid, uuid);
 186 }
 187
 188 struct discover_device *device_lookup_by_label(
 189                 struct device_handler *device_handler,
 190                 const char *label)
 191 {
 192         return device_lookup(device_handler, device_match_label, label);
 193 }
 194
 195 struct discover_device *device_lookup_by_id(
 196                 struct device_handler *device_handler,
 197                 const char *id)
 198 {
 199         return device_lookup(device_handler, device_match_id, id);
 200 }
 201
 202 struct discover_device *device_lookup_by_serial(
 203                 struct device_handler *device_handler,
 204                 const char *serial)
 205 {
 206         return device_lookup(device_handler, device_match_serial, serial);
 207 }
 208
 209 void device_handler_destroy(struct device_handler *handler)
 210 {
 211         talloc_free(handler);
 212 }
 213
 214 static int destroy_device(void *arg)
 215 {
 216         struct discover_device *dev = arg;
 217
 218         umount_device(dev);
 219
 220         return 0;
 221 }
 222
 223 struct discover_device *discover_device_create(struct device_handler *handler,
 224                 const char *id)
 225 {
 226         struct discover_device *dev;
 227
 228         dev = device_lookup_by_id(handler, id);
 229         if (dev)
 230                 return dev;
 231
 232         dev = talloc_zero(handler, struct discover_device);
 233         dev->device = talloc_zero(dev, struct device);
 234         dev->device->id = talloc_strdup(dev->device, id);
 235         list_init(&dev->params);
 236         list_init(&dev->boot_options);
 237
 238         talloc_set_destructor(dev, destroy_device);
 239
 240         return dev;
 241 }
 242
 243 struct discover_device_param {
 244         char                    *name;
 245         char                    *value;
 246         struct list_item        list;
 247 };
 248
 249 void discover_device_set_param(struct discover_device *device,
 250                 const char *name, const char *value)
 251 {
 252         struct discover_device_param *param;
 253         bool found = false;
 254
 255         list_for_each_entry(&device->params, param, list) {
 256                 if (!strcmp(param->name, name)) {
 257                         found = true;
 258                         break;
 259                 }
 260         }
 261
 262         if (!found) {
 263                 if (!value)
 264                         return;
 265                 param = talloc(device, struct discover_device_param);
 266                 param->name = talloc_strdup(param, name);
 267                 list_add(&device->params, &param->list);
 268         } else {
 269                 if (!value) {
 270                         list_remove(&param->list);
 271                         talloc_free(param);
 272                         return;
 273                 }
 274                 talloc_free(param->value);
 275         }
 276
 277         param->value = talloc_strdup(param, value);
 278 }
 279
 280 const char *discover_device_get_param(struct discover_device *device,
 281                 const char *name)
 282 {
 283         struct discover_device_param *param;
 284
 285         list_for_each_entry(&device->params, param, list) {
 286                 if (!strcmp(param->name, name))
 287                         return param->value;
 288         }
 289         return NULL;
 290 }
 291
 292 struct device_handler *device_handler_init(struct discover_server *server,
 293                 struct waitset *waitset, int dry_run)
 294 {
 295         struct device_handler *handler;
 296         int rc;
 297
 298         handler = talloc_zero(NULL, struct device_handler);
 299         handler->server = server;
 300         handler->waitset = waitset;
 301         handler->dry_run = dry_run;
 302         handler->autoboot_enabled = config_get()->autoboot_enabled;
 303
 304         list_init(&handler->unresolved_boot_options);
 305
 306         /* set up our mount point base */
 307         pb_mkdir_recursive(mount_base());
 308
 309         parser_init();
 310
 311         if (config_get()->safe_mode)
 312                 return handler;
 313
 314         rc = device_handler_init_sources(handler);
 315         if (rc) {
 316                 talloc_free(handler);
 317                 return NULL;
 318         }
 319
 320         return handler;
 321 }
 322
 323 void device_handler_reinit(struct device_handler *handler)
 324 {
 325         struct discover_boot_option *opt, *tmp;
 326         struct ramdisk_device *ramdisk;
 327         unsigned int i;
 328
 329         device_handler_cancel_default(handler);
 330
 331         /* free unresolved boot options */
 332         list_for_each_entry_safe(&handler->unresolved_boot_options,
 333                         opt, tmp, list)
 334                 talloc_free(opt);
 335         list_init(&handler->unresolved_boot_options);
 336
 337         /* drop all devices */
 338         for (i = 0; i < handler->n_devices; i++) {
 339                 discover_server_notify_device_remove(handler->server,
 340                                 handler->devices[i]->device);
 341                 ramdisk = handler->devices[i]->ramdisk;
 342                 talloc_free(handler->devices[i]);
 343                 talloc_free(ramdisk);
 344         }
 345
 346         talloc_free(handler->devices);
 347         handler->devices = NULL;
 348         handler->n_devices = 0;
 349         talloc_free(handler->ramdisks);
 350         handler->ramdisks = NULL;
 351         handler->n_ramdisks = 0;
 352
 353         device_handler_reinit_sources(handler);
 354 }
 355
 356 void device_handler_remove(struct device_handler *handler,
 357                 struct discover_device *device)
 358 {
 359         struct discover_boot_option *opt, *tmp;
 360         unsigned int i;
 361
 362         for (i = 0; i < handler->n_devices; i++)
 363                 if (handler->devices[i] == device)
 364                         break;
 365
 366         if (i == handler->n_devices) {
 367                 talloc_free(device);
 368                 return;
 369         }
 370
 371         /* Free any unresolved options, as they're currently allocated
 372          * against the handler */
 373         list_for_each_entry_safe(&handler->unresolved_boot_options,
 374                         opt, tmp, list) {
 375                 if (opt->device != device)
 376                         continue;
 377                 list_remove(&opt->list);
 378                 talloc_free(opt);
 379         }
 380
 381         /* if this is a network device, we have to unregister it from the
 382          * network code */
 383         if (device->device->type == DEVICE_TYPE_NETWORK)
 384                 network_unregister_device(handler->network, device);
 385
 386         handler->n_devices--;
 387         memmove(&handler->devices[i], &handler->devices[i + 1],
 388                 (handler->n_devices - i) * sizeof(handler->devices[0]));
 389         handler->devices = talloc_realloc(handler, handler->devices,
 390                 struct discover_device *, handler->n_devices);
 391
 392         if (device->notified)
 393                 discover_server_notify_device_remove(handler->server,
 394                                                         device->device);
 395
 396         talloc_free(device);
 397 }
 398
 399 void device_handler_boot_status(void *arg, struct boot_status *status)
 400 {
 401         struct device_handler *handler = arg;
 402
 403         discover_server_notify_boot_status(handler->server, status);
 404 }
 405
 406 static void countdown_status(struct device_handler *handler,
 407                 struct discover_boot_option *opt, unsigned int sec)
 408 {
 409         struct boot_status status;
 410
 411         status.type = BOOT_STATUS_INFO;
 412         status.progress = -1;
 413         status.detail = NULL;
 414         status.message = talloc_asprintf(handler,
 415                         _("Booting in %d sec: %s"), sec, opt->option->name);
 416
 417         discover_server_notify_boot_status(handler->server, &status);
 418
 419         talloc_free(status.message);
 420 }
 421
 422 static int default_timeout(void *arg)
 423 {
 424         struct device_handler *handler = arg;
 425         struct discover_boot_option *opt;
 426
 427         if (!handler->default_boot_option)
 428                 return 0;
 429
 430         if (handler->pending_boot)
 431                 return 0;
 432
 433         opt = handler->default_boot_option;
 434
 435         if (handler->sec_to_boot) {
 436                 countdown_status(handler, opt, handler->sec_to_boot);
 437                 handler->sec_to_boot--;
 438                 handler->timeout_waiter = waiter_register_timeout(
 439                                                 handler->waitset, 1000,
 440                                                 default_timeout, handler);
 441                 return 0;
 442         }
 443
 444         handler->timeout_waiter = NULL;
 445
 446         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 447
 448         platform_pre_boot();
 449
 450         handler->pending_boot = boot(handler, handler->default_boot_option,
 451                         NULL, handler->dry_run, device_handler_boot_status,
 452                         handler);
 453         handler->pending_boot_is_default = true;
 454         return 0;
 455 }
 456
 457 struct {
 458         enum ipmi_bootdev       ipmi_type;
 459         enum device_type        device_type;
 460 } device_type_map[] = {
 461         { IPMI_BOOTDEV_NETWORK, DEVICE_TYPE_NETWORK },
 462         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_DISK },
 463         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_USB },
 464         { IPMI_BOOTDEV_CDROM, DEVICE_TYPE_OPTICAL },
 465 };
 466
 467 static bool ipmi_device_type_matches(enum ipmi_bootdev ipmi_type,
 468                 enum device_type device_type)
 469 {
 470         unsigned int i;
 471
 472         for (i = 0; i < ARRAY_SIZE(device_type_map); i++) {
 473                 if (device_type_map[i].device_type == device_type)
 474                         return device_type_map[i].ipmi_type == ipmi_type;
 475         }
 476
 477         return false;
 478 }
 479
 480 static int autoboot_option_priority(const struct config *config,
 481                                 struct discover_boot_option *opt)
 482 {
 483         enum device_type type = opt->device->device->type;
 484         const char *uuid = opt->device->uuid;
 485         struct autoboot_option *auto_opt;
 486         unsigned int i;
 487
 488         for (i = 0; i < config->n_autoboot_opts; i++) {
 489                 auto_opt = &config->autoboot_opts[i];
 490                 if (auto_opt->boot_type == BOOT_DEVICE_UUID)
 491                         if (!strcmp(auto_opt->uuid, uuid))
 492                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 493
 494                 if (auto_opt->boot_type == BOOT_DEVICE_TYPE)
 495                         if (auto_opt->type == type ||
 496                             auto_opt->type == DEVICE_TYPE_ANY)
 497                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 498         }
 499
 500         return -1;
 501 }
 502
 503 /*
 504  * We have different priorities to resolve conflicts between boot options that
 505  * report to be the default for their device. This function assigns a priority
 506  * for these options.
 507  */
 508 static enum default_priority default_option_priority(
 509                 struct discover_boot_option *opt)
 510 {
 511         const struct config *config;
 512
 513         config = config_get();
 514
 515         /* We give highest priority to IPMI-configured boot options. If
 516          * we have an IPMI bootdev configuration set, then we don't allow
 517          * any other defaults */
 518         if (config->ipmi_bootdev) {
 519                 bool ipmi_match = ipmi_device_type_matches(config->ipmi_bootdev,
 520                                 opt->device->device->type);
 521                 if (ipmi_match)
 522                         return DEFAULT_PRIORITY_REMOTE;
 523
 524                 pb_debug("handler: disabled default priority due to "
 525                                 "non-matching IPMI type %x\n",
 526                                 config->ipmi_bootdev);
 527                 return DEFAULT_PRIORITY_DISABLED;
 528         }
 529
 530         /* Next, try to match the option against the user-defined autoboot
 531          * options, either by device UUID or type. */
 532         if (config->n_autoboot_opts) {
 533                 int boot_match = autoboot_option_priority(config, opt);
 534                 if (boot_match > 0)
 535                         return boot_match;
 536         }
 537
 538         /* If the option didn't match any entry in the array, it is disabled */
 539         pb_debug("handler: disabled default priority due to "
 540                         "non-matching UUID or type\n");
 541         return DEFAULT_PRIORITY_DISABLED;
 542 }
 543
 544 static void set_default(struct device_handler *handler,
 545                 struct discover_boot_option *opt)
 546 {
 547         enum default_priority cur_prio, new_prio;
 548
 549         if (!handler->autoboot_enabled)
 550                 return;
 551
 552         pb_debug("handler: new default option: %s\n", opt->option->id);
 553
 554         new_prio = default_option_priority(opt);
 555
 556         /* Anything outside our range prevents a default boot */
 557         if (new_prio >= DEFAULT_PRIORITY_DISABLED)
 558                 return;
 559
 560         pb_debug("handler: calculated priority %d\n", new_prio);
 561
 562         /* Resolve any conflicts: if we have a new default option, it only
 563          * replaces the current if it has a higher priority. */
 564         if (handler->default_boot_option) {
 565
 566                 cur_prio = handler->default_boot_option_priority;
 567
 568                 if (new_prio < cur_prio) {
 569                         pb_log("handler: new prio %d beats "
 570                                         "old prio %d for %s\n",
 571                                         new_prio, cur_prio,
 572                                         handler->default_boot_option
 573                                                 ->option->id);
 574                         handler->default_boot_option = opt;
 575                         handler->default_boot_option_priority = new_prio;
 576                         /* extend the timeout a little, so the user sees some
 577                          * indication of the change */
 578                         handler->sec_to_boot += 2;
 579                 }
 580
 581                 return;
 582         }
 583
 584         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
 585         handler->default_boot_option = opt;
 586         handler->default_boot_option_priority = new_prio;
 587
 588         pb_log("handler: boot option %s set as default, timeout %u sec.\n",
 589                opt->option->id, handler->sec_to_boot);
 590
 591         default_timeout(handler);
 592 }
 593
 594 static bool resource_is_resolved(struct resource *res)
 595 {
 596         return !res || res->resolved;
 597 }
 598
 599 /* We only use this in an assert, which will disappear if we're compiling
 600  * with NDEBUG, so we need the 'used' attribute for these builds */
 601 static bool __attribute__((used)) boot_option_is_resolved(
 602                 struct discover_boot_option *opt)
 603 {
 604         return resource_is_resolved(opt->boot_image) &&
 605                 resource_is_resolved(opt->initrd) &&
 606                 resource_is_resolved(opt->dtb) &&
 607                 resource_is_resolved(opt->icon);
 608 }
 609
 610 static bool resource_resolve(struct resource *res, const char *name,
 611                 struct discover_boot_option *opt,
 612                 struct device_handler *handler)
 613 {
 614         struct parser *parser = opt->source;
 615
 616         if (resource_is_resolved(res))
 617                 return true;
 618
 619         pb_debug("Attempting to resolve resource %s->%s with parser %s\n",
 620                         opt->option->id, name, parser->name);
 621         parser->resolve_resource(handler, res);
 622
 623         return res->resolved;
 624 }
 625
 626 static bool boot_option_resolve(struct discover_boot_option *opt,
 627                 struct device_handler *handler)
 628 {
 629         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
 630                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
 631                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
 632                 resource_resolve(opt->icon, "icon", opt, handler);
 633 }
 634
 635 static void boot_option_finalise(struct device_handler *handler,
 636                 struct discover_boot_option *opt)
 637 {
 638         assert(boot_option_is_resolved(opt));
 639
 640         /* check that the parsers haven't set any of the final data */
 641         assert(!opt->option->boot_image_file);
 642         assert(!opt->option->initrd_file);
 643         assert(!opt->option->dtb_file);
 644         assert(!opt->option->icon_file);
 645         assert(!opt->option->device_id);
 646
 647         if (opt->boot_image)
 648                 opt->option->boot_image_file = opt->boot_image->url->full;
 649         if (opt->initrd)
 650                 opt->option->initrd_file = opt->initrd->url->full;
 651         if (opt->dtb)
 652                 opt->option->dtb_file = opt->dtb->url->full;
 653         if (opt->icon)
 654                 opt->option->icon_file = opt->icon->url->full;
 655
 656         opt->option->device_id = opt->device->device->id;
 657
 658         if (opt->option->is_default)
 659                 set_default(handler, opt);
 660 }
 661
 662 static void notify_boot_option(struct device_handler *handler,
 663                 struct discover_boot_option *opt)
 664 {
 665         struct discover_device *dev = opt->device;
 666
 667         if (!dev->notified)
 668                 discover_server_notify_device_add(handler->server,
 669                                                   opt->device->device);
 670         dev->notified = true;
 671         discover_server_notify_boot_option_add(handler->server, opt->option);
 672 }
 673
 674 static void process_boot_option_queue(struct device_handler *handler)
 675 {
 676         struct discover_boot_option *opt, *tmp;
 677
 678         list_for_each_entry_safe(&handler->unresolved_boot_options,
 679                         opt, tmp, list) {
 680
 681                 pb_debug("queue: attempting resolution for %s\n",
 682                                 opt->option->id);
 683
 684                 if (!boot_option_resolve(opt, handler))
 685                         continue;
 686
 687                 pb_debug("\tresolved!\n");
 688
 689                 list_remove(&opt->list);
 690                 list_add_tail(&opt->device->boot_options, &opt->list);
 691                 talloc_steal(opt->device, opt);
 692                 boot_option_finalise(handler, opt);
 693                 notify_boot_option(handler, opt);
 694         }
 695 }
 696
 697 struct discover_context *device_handler_discover_context_create(
 698                 struct device_handler *handler,
 699                 struct discover_device *device)
 700 {
 701         struct discover_context *ctx;
 702
 703         ctx = talloc_zero(handler, struct discover_context);
 704         ctx->device = device;
 705         ctx->network = handler->network;
 706         list_init(&ctx->boot_options);
 707
 708         return ctx;
 709 }
 710
 711 void device_handler_add_device(struct device_handler *handler,
 712                 struct discover_device *device)
 713 {
 714         handler->n_devices++;
 715         handler->devices = talloc_realloc(handler, handler->devices,
 716                                 struct discover_device *, handler->n_devices);
 717         handler->devices[handler->n_devices - 1] = device;
 718
 719         if (device->device->type == DEVICE_TYPE_NETWORK)
 720                 network_register_device(handler->network, device);
 721 }
 722
 723 void device_handler_add_ramdisk(struct device_handler *handler,
 724                 const char *path)
 725 {
 726         struct ramdisk_device *dev;
 727         unsigned int i;
 728
 729         if (!path)
 730                 return;
 731
 732         for (i = 0; i < handler->n_ramdisks; i++)
 733                 if (!strcmp(handler->ramdisks[i]->path, path))
 734                         return;
 735
 736         dev = talloc_zero(handler, struct ramdisk_device);
 737         if (!dev) {
 738                 pb_log("Failed to allocate memory to track %s\n", path);
 739                 return;
 740         }
 741
 742         dev->path = talloc_strdup(handler, path);
 743
 744         handler->ramdisks = talloc_realloc(handler, handler->ramdisks,
 745                                 struct ramdisk_device *,
 746                                 handler->n_ramdisks + 1);
 747         if (!handler->ramdisks) {
 748                 pb_log("Failed to reallocate memory"
 749                        "- ramdisk tracking inconsistent!\n");
 750                 return;
 751         }
 752
 753         handler->ramdisks[i] = dev;
 754         i = handler->n_ramdisks++;
 755 }
 756
 757 struct ramdisk_device *device_handler_get_ramdisk(
 758                 struct device_handler *handler)
 759 {
 760         unsigned int i;
 761         char *name;
 762         dev_t id;
 763
 764         /* Check if free ramdisk exists */
 765         for (i = 0; i < handler->n_ramdisks; i++)
 766                 if (!handler->ramdisks[i]->snapshot &&
 767                     !handler->ramdisks[i]->origin &&
 768                     !handler->ramdisks[i]->base)
 769                         return handler->ramdisks[i];
 770
 771         /* Otherwise create a new one */
 772         name = talloc_asprintf(handler, "/dev/ram%d",
 773                         handler->n_ramdisks);
 774         if (!name) {
 775                 pb_debug("Failed to allocate memory to name /dev/ram%d",
 776                         handler->n_ramdisks);
 777                 return NULL;
 778         }
 779
 780         id = makedev(1, handler->n_ramdisks);
 781         if (mknod(name, S_IFBLK, id)) {
 782                 if (errno == EEXIST) {
 783                         /* We haven't yet received updates for existing
 784                          * ramdisks - add and use this one */
 785                         pb_debug("Using untracked ramdisk %s\n", name);
 786                 } else {
 787                         pb_log("Failed to create new ramdisk %s: %s\n",
 788                                name, strerror(errno));
 789                         return NULL;
 790                 }
 791         }
 792         device_handler_add_ramdisk(handler, name);
 793         talloc_free(name);
 794
 795         return handler->ramdisks[i];
 796 }
 797
 798 void device_handler_release_ramdisk(struct discover_device *device)
 799 {
 800         struct ramdisk_device *ramdisk = device->ramdisk;
 801
 802         talloc_free(ramdisk->snapshot);
 803         talloc_free(ramdisk->origin);
 804         talloc_free(ramdisk->base);
 805
 806         ramdisk->snapshot = ramdisk->origin = ramdisk->base = NULL;
 807         ramdisk->sectors = 0;
 808
 809         device->ramdisk = NULL;
 810 }
 811
 812 /* Start discovery on a hotplugged device. The device will be in our devices
 813  * array, but has only just been initialised by the hotplug source.
 814  */
 815 int device_handler_discover(struct device_handler *handler,
 816                 struct discover_device *dev)
 817 {
 818         struct discover_context *ctx;
 819         struct boot_status *status;
 820         int rc;
 821
 822         status = talloc_zero(handler, struct boot_status);
 823         status->type = BOOT_STATUS_INFO;
 824         /*
 825          * TRANSLATORS: this string will be passed the type and identifier
 826          * of the device. For example, the first parameter could be "Disk",
 827          * (which will be translated accordingly) and the second a Linux device
 828          * identifier like 'sda1' (which will not be translated)
 829          */
 830         status->message = talloc_asprintf(status, _("Processing %s device %s"),
 831                                 device_type_display_name(dev->device->type),
 832                                 dev->device->id);
 833         device_handler_boot_status(handler, status);
 834
 835         process_boot_option_queue(handler);
 836
 837         /* create our context */
 838         ctx = device_handler_discover_context_create(handler, dev);
 839
 840         rc = mount_device(dev);
 841         if (rc)
 842                 goto out;
 843
 844         /* add this device to our system info */
 845         system_info_register_blockdev(dev->device->id, dev->uuid,
 846                         dev->mount_path);
 847
 848         /* run the parsers. This will populate the ctx's boot_option list. */
 849         iterate_parsers(ctx);
 850
 851         /* add discovered stuff to the handler */
 852         device_handler_discover_context_commit(handler, ctx);
 853
 854 out:
 855         /*
 856          * TRANSLATORS: the format specifier in this string is a Linux
 857          * device identifier, like 'sda1'
 858          */
 859         status->message = talloc_asprintf(status,_("Processing %s complete"),
 860                                 dev->device->id);
 861         device_handler_boot_status(handler, status);
 862
 863         talloc_free(status);
 864         talloc_free(ctx);
 865
 866         return 0;
 867 }
 868
 869 /* Incoming dhcp event */
 870 int device_handler_dhcp(struct device_handler *handler,
 871                 struct discover_device *dev, struct event *event)
 872 {
 873         struct discover_context *ctx;
 874         struct boot_status *status;
 875
 876         status = talloc_zero(handler, struct boot_status);
 877         status->type = BOOT_STATUS_INFO;
 878         /*
 879          * TRANSLATORS: this format specifier will be the name of a network
 880          * device, like 'eth0'.
 881          */
 882         status->message = talloc_asprintf(status, _("Processing dhcp event on %s"),
 883                                 dev->device->id);
 884         device_handler_boot_status(handler, status);
 885
 886         /* create our context */
 887         ctx = device_handler_discover_context_create(handler, dev);
 888         ctx->event = event;
 889
 890         iterate_parsers(ctx);
 891
 892         device_handler_discover_context_commit(handler, ctx);
 893
 894         /*
 895          * TRANSLATORS: this format specifier will be the name of a network
 896          * device, like 'eth0'.
 897          */
 898         status->message = talloc_asprintf(status,_("Processing %s complete"),
 899                                 dev->device->id);
 900         device_handler_boot_status(handler, status);
 901
 902         talloc_free(status);
 903         talloc_free(ctx);
 904
 905         return 0;
 906 }
 907
 908 /* incoming conf event */
 909 int device_handler_conf(struct device_handler *handler,
 910                 struct discover_device *dev, struct pb_url *url)
 911 {
 912         struct discover_context *ctx;
 913         struct boot_status *status;
 914
 915         status = talloc_zero(handler, struct boot_status);
 916         status->type = BOOT_STATUS_INFO;
 917         status->message = talloc_asprintf(status, _("Processing user config"));
 918         device_handler_boot_status(handler, status);
 919
 920         /* create our context */
 921         ctx = device_handler_discover_context_create(handler, dev);
 922         ctx->conf_url = url;
 923
 924         iterate_parsers(ctx);
 925
 926         device_handler_discover_context_commit(handler, ctx);
 927
 928         status->message = talloc_asprintf(status,
 929                                 _("Processing user config complete"));
 930         device_handler_boot_status(handler, status);
 931
 932         talloc_free(status);
 933         talloc_free(ctx);
 934
 935         return 0;
 936 }
 937
 938 static struct discover_boot_option *find_boot_option_by_id(
 939                 struct device_handler *handler, const char *id)
 940 {
 941         unsigned int i;
 942
 943         for (i = 0; i < handler->n_devices; i++) {
 944                 struct discover_device *dev = handler->devices[i];
 945                 struct discover_boot_option *opt;
 946
 947                 list_for_each_entry(&dev->boot_options, opt, list)
 948                         if (!strcmp(opt->option->id, id))
 949                                 return opt;
 950         }
 951
 952         return NULL;
 953 }
 954
 955 void device_handler_boot(struct device_handler *handler,
 956                 struct boot_command *cmd)
 957 {
 958         struct discover_boot_option *opt = NULL;
 959
 960         if (cmd->option_id && strlen(cmd->option_id))
 961                 opt = find_boot_option_by_id(handler, cmd->option_id);
 962
 963         if (handler->pending_boot)
 964                 boot_cancel(handler->pending_boot);
 965
 966         platform_pre_boot();
 967
 968         handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
 969                         device_handler_boot_status, handler);
 970         handler->pending_boot_is_default = false;
 971 }
 972
 973 void device_handler_cancel_default(struct device_handler *handler)
 974 {
 975         struct boot_status status;
 976
 977         if (handler->timeout_waiter)
 978                 waiter_remove(handler->timeout_waiter);
 979
 980         handler->timeout_waiter = NULL;
 981         handler->autoboot_enabled = false;
 982
 983         /* we only send status if we had a default boot option queued */
 984         if (!handler->default_boot_option)
 985                 return;
 986
 987         pb_log("Cancelling default boot option\n");
 988
 989         if (handler->pending_boot && handler->pending_boot_is_default) {
 990                 boot_cancel(handler->pending_boot);
 991                 handler->pending_boot = NULL;
 992                 handler->pending_boot_is_default = false;
 993         }
 994
 995         handler->default_boot_option = NULL;
 996
 997         status.type = BOOT_STATUS_INFO;
 998         status.progress = -1;
 999         status.detail = NULL;
1000         status.message = _("Default boot cancelled");
1001
1002         discover_server_notify_boot_status(handler->server, &status);
1003 }
1004
1005 void device_handler_update_config(struct device_handler *handler,
1006                 struct config *config)
1007 {
1008         int rc;
1009
1010         rc = config_set(config);
1011         if (rc)
1012                 return;
1013
1014         discover_server_notify_config(handler->server, config);
1015         device_handler_update_lang(config->lang);
1016         device_handler_reinit(handler);
1017 }
1018
1019 static char *device_from_addr(void *ctx, struct pb_url *url)
1020 {
1021         char *ipaddr, *buf, *tok, *dev = NULL;
1022         const char *delim = " ";
1023         struct sockaddr_in *ip;
1024         struct sockaddr_in si;
1025         struct addrinfo *res;
1026         struct process *p;
1027         int rc;
1028
1029         /* Note: IPv4 only */
1030         rc = inet_pton(AF_INET, url->host, &(si.sin_addr));
1031         if (rc > 0) {
1032                 ipaddr = url->host;
1033         } else {
1034                 /* need to turn hostname into a valid IP */
1035                 rc = getaddrinfo(url->host, NULL, NULL, &res);
1036                 if (rc) {
1037                         pb_debug("%s: Invalid URL\n",__func__);
1038                         return NULL;
1039                 }
1040                 ipaddr = talloc_array(ctx,char,INET_ADDRSTRLEN);
1041                 ip = (struct sockaddr_in *) res->ai_addr;
1042                 inet_ntop(AF_INET, &(ip->sin_addr), ipaddr, INET_ADDRSTRLEN);
1043                 freeaddrinfo(res);
1044         }
1045
1046         const char *argv[] = {
1047                 pb_system_apps.ip,
1048                 "route", "show", "to", "match",
1049                 ipaddr,
1050                 NULL
1051         };
1052
1053         p = process_create(ctx);
1054
1055         p->path = pb_system_apps.ip;
1056         p->argv = argv;
1057         p->keep_stdout = true;
1058
1059         rc = process_run_sync(p);
1060
1061         if (rc || p->exit_status) {
1062                 /* ip has complained for some reason; most likely
1063                  * there is no route to the host - bail out */
1064                 pb_debug("%s: `ip` returns non-zero exit status\n", __func__);
1065                 pb_debug("ip buf: %s\n", p->stdout_buf);
1066                 process_release(p);
1067                 return NULL;
1068         }
1069
1070         buf = p->stdout_buf;
1071         /* If a route is found, ip-route output will be of the form
1072          * "... dev DEVNAME ... " */
1073         tok = strtok(buf, delim);
1074         while (tok) {
1075                 if (!strcmp(tok, "dev")) {
1076                         tok = strtok(NULL, delim);
1077                         dev = talloc_strdup(ctx, tok);
1078                         break;
1079                 }
1080                 tok = strtok(NULL, delim);
1081         }
1082
1083         process_release(p);
1084         if (dev)
1085                 pb_debug("%s: Found interface '%s'\n", __func__,dev);
1086         return dev;
1087 }
1088
1089 void device_handler_process_url(struct device_handler *handler,
1090                 const char *url, const char *mac, const char *ip)
1091 {
1092         struct discover_context *ctx;
1093         struct discover_device *dev;
1094         struct boot_status *status;
1095         struct pb_url *pb_url;
1096         struct event *event;
1097         struct param *param;
1098
1099         status = talloc(handler, struct boot_status);
1100
1101         status->type = BOOT_STATUS_ERROR;
1102         status->progress = 0;
1103         status->detail = talloc_asprintf(status,
1104                         _("Received config URL %s"), url);
1105
1106         if (!handler->network) {
1107                 status->message = talloc_asprintf(handler,
1108                                         _("No network configured"));
1109                 goto msg;
1110         }
1111
1112         event = talloc(handler, struct event);
1113         event->type = EVENT_TYPE_USER;
1114         event->action = EVENT_ACTION_CONF;
1115
1116         if (url[strlen(url) - 1] == '/') {
1117                 event->params = talloc_array(event, struct param, 3);
1118                 param = &event->params[0];
1119                 param->name = talloc_strdup(event, "pxepathprefix");
1120                 param->value = talloc_strdup(event, url);
1121                 param = &event->params[1];
1122                 param->name = talloc_strdup(event, "mac");
1123                 param->value = talloc_strdup(event, mac);
1124                 param = &event->params[2];
1125                 param->name = talloc_strdup(event, "ip");
1126                 param->value = talloc_strdup(event, ip);
1127                 event->n_params = 3;
1128         } else {
1129                 event->params = talloc_array(event, struct param, 1);
1130                 param = &event->params[0];
1131                 param->name = talloc_strdup(event, "pxeconffile");
1132                 param->value = talloc_strdup(event, url);
1133                 event->n_params = 1;
1134         }
1135
1136         pb_url = pb_url_parse(event, event->params->value);
1137         if (!pb_url || (pb_url->scheme != pb_url_file && !pb_url->host)) {
1138                 status->message = talloc_asprintf(handler,
1139                                         _("Invalid config URL!"));
1140                 goto msg;
1141         }
1142
1143         if (pb_url->scheme == pb_url_file)
1144                 event->device = talloc_asprintf(event, "local");
1145         else
1146                 event->device = device_from_addr(event, pb_url);
1147
1148         if (!event->device) {
1149                 status->message = talloc_asprintf(status,
1150                                         _("Unable to route to host %s"),
1151                                         pb_url->host);
1152                 goto msg;
1153         }
1154
1155         dev = discover_device_create(handler, event->device);
1156         if (pb_url->scheme == pb_url_file)
1157                 dev->device->type = DEVICE_TYPE_ANY;
1158         ctx = device_handler_discover_context_create(handler, dev);
1159         ctx->event = event;
1160
1161         iterate_parsers(ctx);
1162
1163         device_handler_discover_context_commit(handler, ctx);
1164
1165         talloc_free(ctx);
1166
1167         status->type = BOOT_STATUS_INFO;
1168         status->message = talloc_asprintf(status, _("Config file %s parsed"),
1169                                         pb_url->file);
1170 msg:
1171         device_handler_boot_status(handler, status);
1172         talloc_free(status);
1173 }
1174
1175 #ifndef PETITBOOT_TEST
1176
1177 /**
1178  * context_commit - Commit a temporary discovery context to the handler,
1179  * and notify the clients about any new options / devices
1180  */
1181 void device_handler_discover_context_commit(struct device_handler *handler,
1182                 struct discover_context *ctx)
1183 {
1184         struct discover_device *dev = ctx->device;
1185         struct discover_boot_option *opt, *tmp;
1186
1187         if (!device_lookup_by_id(handler, dev->device->id))
1188                 device_handler_add_device(handler, dev);
1189
1190         /* move boot options from the context to the device */
1191         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
1192                 list_remove(&opt->list);
1193
1194                 if (boot_option_resolve(opt, handler)) {
1195                         pb_log("boot option %s is resolved, "
1196                                         "sending to clients\n",
1197                                         opt->option->id);
1198                         list_add_tail(&dev->boot_options, &opt->list);
1199                         talloc_steal(dev, opt);
1200                         boot_option_finalise(handler, opt);
1201                         notify_boot_option(handler, opt);
1202                 } else {
1203                         if (!opt->source->resolve_resource) {
1204                                 pb_log("parser %s gave us an unresolved "
1205                                         "resource (%s), but no way to "
1206                                         "resolve it\n",
1207                                         opt->source->name, opt->option->id);
1208                                 talloc_free(opt);
1209                         } else {
1210                                 pb_log("boot option %s is unresolved, "
1211                                                 "adding to queue\n",
1212                                                 opt->option->id);
1213                                 list_add(&handler->unresolved_boot_options,
1214                                                 &opt->list);
1215                                 talloc_steal(handler, opt);
1216                         }
1217                 }
1218         }
1219 }
1220
1221 static void device_handler_update_lang(const char *lang)
1222 {
1223         const char *cur_lang;
1224
1225         if (!lang)
1226                 return;
1227
1228         cur_lang = setlocale(LC_ALL, NULL);
1229         if (cur_lang && !strcmp(cur_lang, lang))
1230                 return;
1231
1232         setlocale(LC_ALL, lang);
1233 }
1234
1235 static int device_handler_init_sources(struct device_handler *handler)
1236 {
1237         /* init our device sources: udev, network and user events */
1238         handler->udev = udev_init(handler, handler->waitset);
1239         if (!handler->udev)
1240                 return -1;
1241
1242         handler->network = network_init(handler, handler->waitset,
1243                         handler->dry_run);
1244         if (!handler->network)
1245                 return -1;
1246
1247         handler->user_event = user_event_init(handler, handler->waitset);
1248         if (!handler->user_event)
1249                 return -1;
1250
1251         return 0;
1252 }
1253
1254 static void device_handler_reinit_sources(struct device_handler *handler)
1255 {
1256         /* if we haven't initialised sources previously (becuase we started in
1257          * safe mode), then init once here. */
1258         if (!(handler->udev || handler->network || handler->user_event)) {
1259                 device_handler_init_sources(handler);
1260                 return;
1261         }
1262
1263         udev_reinit(handler->udev);
1264
1265         network_shutdown(handler->network);
1266         handler->network = network_init(handler, handler->waitset,
1267                         handler->dry_run);
1268 }
1269
1270 static inline const char *get_device_path(struct discover_device *dev)
1271 {
1272         return dev->ramdisk ? dev->ramdisk->snapshot : dev->device_path;
1273 }
1274
1275 static char *check_subvols(struct discover_device *dev)
1276 {
1277         const char *fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1278         struct stat sb;
1279         char *path;
1280         int rc;
1281
1282         if (strncmp(fstype, "btrfs", strlen("btrfs")))
1283                 return dev->mount_path;
1284
1285         /* On btrfs a device's root may be under a subvolume path */
1286         path = join_paths(dev, dev->mount_path, "@");
1287         rc = stat(path, &sb);
1288         if (!rc && S_ISDIR(sb.st_mode)) {
1289                 pb_debug("Using '%s' for btrfs root path\n", path);
1290                 return path;
1291         }
1292
1293         talloc_free(path);
1294         return dev->mount_path;
1295 }
1296
1297 static bool check_existing_mount(struct discover_device *dev)
1298 {
1299         struct stat devstat, mntstat;
1300         const char *device_path;
1301         struct mntent *mnt;
1302         FILE *fp;
1303         int rc;
1304
1305         device_path = get_device_path(dev);
1306
1307         rc = stat(device_path, &devstat);
1308         if (rc) {
1309                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
1310                 return false;
1311         }
1312
1313         if (!S_ISBLK(devstat.st_mode)) {
1314                 pb_debug("%s: %s isn't a block device?\n", __func__,
1315                                 dev->device_path);
1316                 return false;
1317         }
1318
1319         fp = fopen("/proc/self/mounts", "r");
1320
1321         for (;;) {
1322                 mnt = getmntent(fp);
1323                 if (!mnt)
1324                         break;
1325
1326                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
1327                         continue;
1328
1329                 rc = stat(mnt->mnt_fsname, &mntstat);
1330                 if (rc)
1331                         continue;
1332
1333                 if (!S_ISBLK(mntstat.st_mode))
1334                         continue;
1335
1336                 if (mntstat.st_rdev == devstat.st_rdev) {
1337                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
1338                         dev->root_path = check_subvols(dev);
1339                         dev->mounted_rw = !!hasmntopt(mnt, "rw");
1340                         dev->mounted = true;
1341                         dev->unmount = false;
1342
1343                         pb_debug("%s: %s is already mounted (r%c) at %s\n",
1344                                         __func__, dev->device_path,
1345                                         dev->mounted_rw ? 'w' : 'o',
1346                                         mnt->mnt_dir);
1347                         break;
1348                 }
1349         }
1350
1351         fclose(fp);
1352
1353         return mnt != NULL;
1354 }
1355
1356 /*
1357  * Attempt to mount a filesystem safely, while handling certain filesytem-
1358  * specific options
1359  */
1360 static int try_mount(const char *device_path, const char *mount_path,
1361                              const char *fstype, unsigned long flags,
1362                              bool have_snapshot)
1363 {
1364         const char *fs, *safe_opts;
1365         int rc;
1366
1367         /* Mount ext3 as ext4 instead so 'norecovery' can be used */
1368         if (strncmp(fstype, "ext3", strlen("ext3")) == 0) {
1369                 pb_debug("Mounting ext3 filesystem as ext4\n");
1370                 fs = "ext4";
1371         } else
1372                 fs = fstype;
1373
1374         if (strncmp(fs, "xfs", strlen("xfs")) == 0 ||
1375             strncmp(fs, "ext4", strlen("ext4")) == 0)
1376                 safe_opts = "norecovery";
1377         else
1378                 safe_opts = NULL;
1379
1380         errno = 0;
1381         /* If no snapshot is available don't attempt recovery */
1382         if (!have_snapshot)
1383                 return mount(device_path, mount_path, fs, flags, safe_opts);
1384
1385         rc = mount(device_path, mount_path, fs, flags, NULL);
1386
1387         if (!rc)
1388                 return rc;
1389
1390         /* Mounting failed; some filesystems will fail to mount if a recovery
1391          * journal exists (eg. cross-endian XFS), so try again with norecovery
1392          * where that option is available.
1393          * If mounting read-write just return the error as norecovery is not a
1394          * valid option */
1395         if ((flags & MS_RDONLY) != MS_RDONLY || !safe_opts)
1396                 return rc;
1397
1398         errno = 0;
1399         return mount(device_path, mount_path, fs, flags, safe_opts);
1400 }
1401
1402 static int mount_device(struct discover_device *dev)
1403 {
1404         const char *fstype, *device_path;
1405         int rc;
1406
1407         if (!dev->device_path)
1408                 return -1;
1409
1410         if (dev->mounted)
1411                 return 0;
1412
1413         if (check_existing_mount(dev))
1414                 return 0;
1415
1416         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1417         if (!fstype)
1418                 return 0;
1419
1420         dev->mount_path = join_paths(dev, mount_base(),
1421                                         dev->device_path);
1422
1423         if (pb_mkdir_recursive(dev->mount_path)) {
1424                 pb_log("couldn't create mount directory %s: %s\n",
1425                                 dev->mount_path, strerror(errno));
1426                 goto err_free;
1427         }
1428
1429         device_path = get_device_path(dev);
1430
1431         pb_log("mounting device %s read-only\n", dev->device_path);
1432         rc = try_mount(device_path, dev->mount_path, fstype,
1433                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1434
1435         if (!rc) {
1436                 dev->mounted = true;
1437                 dev->mounted_rw = false;
1438                 dev->unmount = true;
1439                 dev->root_path = check_subvols(dev);
1440                 return 0;
1441         }
1442
1443         pb_log("couldn't mount device %s: mount failed: %s\n",
1444                         device_path, strerror(errno));
1445
1446         /* If mount fails clean up any snapshot */
1447         devmapper_destroy_snapshot(dev);
1448
1449         pb_rmdir_recursive(mount_base(), dev->mount_path);
1450 err_free:
1451         talloc_free(dev->mount_path);
1452         dev->mount_path = NULL;
1453         return -1;
1454 }
1455
1456 static int umount_device(struct discover_device *dev)
1457 {
1458         const char *device_path;
1459         int rc;
1460
1461         if (!dev->mounted || !dev->unmount)
1462                 return 0;
1463
1464         device_path = get_device_path(dev);
1465
1466         pb_log("unmounting device %s\n", device_path);
1467         rc = umount(dev->mount_path);
1468         if (rc)
1469                 return -1;
1470
1471         dev->mounted = false;
1472         devmapper_destroy_snapshot(dev);
1473
1474         pb_rmdir_recursive(mount_base(), dev->mount_path);
1475
1476         talloc_free(dev->mount_path);
1477         dev->mount_path = NULL;
1478         dev->root_path = NULL;
1479
1480         return 0;
1481 }
1482
1483 int device_request_write(struct discover_device *dev, bool *release)
1484 {
1485         const char *fstype, *device_path;
1486         const struct config *config;
1487         int rc;
1488
1489         *release = false;
1490
1491         config = config_get();
1492         if (!config->allow_writes)
1493                 return -1;
1494
1495         if (!dev->mounted)
1496                 return -1;
1497
1498         if (dev->mounted_rw)
1499                 return 0;
1500
1501         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1502
1503         device_path = get_device_path(dev);
1504
1505         pb_log("remounting device %s read-write\n", device_path);
1506
1507         rc = umount(dev->mount_path);
1508         if (rc) {
1509                 pb_log("Failed to unmount %s: %s\n",
1510                        dev->mount_path, strerror(errno));
1511                 return -1;
1512         }
1513
1514         rc = try_mount(device_path, dev->mount_path, fstype,
1515                        MS_SILENT, dev->ramdisk);
1516         if (rc)
1517                 goto mount_ro;
1518
1519         dev->mounted_rw = true;
1520         *release = true;
1521         return 0;
1522
1523 mount_ro:
1524         pb_log("Unable to remount device %s read-write: %s\n",
1525                device_path, strerror(errno));
1526         rc = try_mount(device_path, dev->mount_path, fstype,
1527                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1528         if (rc)
1529                 pb_log("Unable to recover mount for %s: %s\n",
1530                        device_path, strerror(errno));
1531         return -1;
1532 }
1533
1534 void device_release_write(struct discover_device *dev, bool release)
1535 {
1536         const char *fstype, *device_path;
1537
1538         if (!release)
1539                 return;
1540
1541         device_path = get_device_path(dev);
1542
1543         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1544
1545         pb_log("remounting device %s read-only\n", device_path);
1546
1547         if (umount(dev->mount_path)) {
1548                 pb_log("Failed to unmount %s\n", dev->mount_path);
1549                 return;
1550         }
1551         dev->mounted_rw = dev->mounted = false;
1552
1553         if (dev->ramdisk) {
1554                 devmapper_merge_snapshot(dev);
1555                 /* device_path becomes stale after merge */
1556                 device_path = get_device_path(dev);
1557         }
1558
1559         if (try_mount(device_path, dev->mount_path, fstype,
1560                        MS_RDONLY | MS_SILENT, dev->ramdisk))
1561                 pb_log("Failed to remount %s read-only: %s\n",
1562                        device_path, strerror(errno));
1563         else
1564                 dev->mounted = true;
1565 }
1566
1567 #else
1568
1569 void device_handler_discover_context_commit(
1570                 struct device_handler *handler __attribute__((unused)),
1571                 struct discover_context *ctx __attribute__((unused)))
1572 {
1573         pb_log("%s stubbed out for test cases\n", __func__);
1574 }
1575
1576 static void device_handler_update_lang(const char *lang __attribute__((unused)))
1577 {
1578 }
1579
1580 static int device_handler_init_sources(
1581                 struct device_handler *handler __attribute__((unused)))
1582 {
1583         return 0;
1584 }
1585
1586 static void device_handler_reinit_sources(
1587                 struct device_handler *handler __attribute__((unused)))
1588 {
1589 }
1590
1591 static int umount_device(struct discover_device *dev __attribute__((unused)))
1592 {
1593         return 0;
1594 }
1595
1596 static int __attribute__((unused)) mount_device(
1597                 struct discover_device *dev __attribute__((unused)))
1598 {
1599         return 0;
1600 }
1601
1602 int device_request_write(struct discover_device *dev __attribute__((unused)),
1603                 bool *release)
1604 {
1605         *release = true;
1606         return 0;
1607 }
1608
1609 void device_release_write(struct discover_device *dev __attribute__((unused)),
1610         bool release __attribute__((unused)))
1611 {
1612 }
1613
1614 #endif