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 *uuid, const char *id)
 225 {
 226         struct discover_device *dev;
 227
 228         if (uuid)
 229                 dev = device_lookup_by_uuid(handler, uuid);
 230         else
 231                 dev = device_lookup_by_id(handler, id);
 232
 233         if (dev)
 234                 return dev;
 235
 236         dev = talloc_zero(handler, struct discover_device);
 237         dev->device = talloc_zero(dev, struct device);
 238         dev->device->id = talloc_strdup(dev->device, id);
 239         dev->uuid = talloc_strdup(dev, uuid);
 240         list_init(&dev->params);
 241         list_init(&dev->boot_options);
 242
 243         talloc_set_destructor(dev, destroy_device);
 244
 245         return dev;
 246 }
 247
 248 struct discover_device_param {
 249         char                    *name;
 250         char                    *value;
 251         struct list_item        list;
 252 };
 253
 254 void discover_device_set_param(struct discover_device *device,
 255                 const char *name, const char *value)
 256 {
 257         struct discover_device_param *param;
 258         bool found = false;
 259
 260         list_for_each_entry(&device->params, param, list) {
 261                 if (!strcmp(param->name, name)) {
 262                         found = true;
 263                         break;
 264                 }
 265         }
 266
 267         if (!found) {
 268                 if (!value)
 269                         return;
 270                 param = talloc(device, struct discover_device_param);
 271                 param->name = talloc_strdup(param, name);
 272                 list_add(&device->params, &param->list);
 273         } else {
 274                 if (!value) {
 275                         list_remove(&param->list);
 276                         talloc_free(param);
 277                         return;
 278                 }
 279                 talloc_free(param->value);
 280         }
 281
 282         param->value = talloc_strdup(param, value);
 283 }
 284
 285 const char *discover_device_get_param(struct discover_device *device,
 286                 const char *name)
 287 {
 288         struct discover_device_param *param;
 289
 290         list_for_each_entry(&device->params, param, list) {
 291                 if (!strcmp(param->name, name))
 292                         return param->value;
 293         }
 294         return NULL;
 295 }
 296
 297 struct device_handler *device_handler_init(struct discover_server *server,
 298                 struct waitset *waitset, int dry_run)
 299 {
 300         struct device_handler *handler;
 301         int rc;
 302
 303         handler = talloc_zero(NULL, struct device_handler);
 304         handler->server = server;
 305         handler->waitset = waitset;
 306         handler->dry_run = dry_run;
 307         handler->autoboot_enabled = config_get()->autoboot_enabled;
 308
 309         list_init(&handler->unresolved_boot_options);
 310
 311         /* set up our mount point base */
 312         pb_mkdir_recursive(mount_base());
 313
 314         parser_init();
 315
 316         if (config_get()->safe_mode)
 317                 return handler;
 318
 319         rc = device_handler_init_sources(handler);
 320         if (rc) {
 321                 talloc_free(handler);
 322                 return NULL;
 323         }
 324
 325         return handler;
 326 }
 327
 328 void device_handler_reinit(struct device_handler *handler)
 329 {
 330         struct discover_boot_option *opt, *tmp;
 331         struct ramdisk_device *ramdisk;
 332         unsigned int i;
 333
 334         device_handler_cancel_default(handler);
 335
 336         /* free unresolved boot options */
 337         list_for_each_entry_safe(&handler->unresolved_boot_options,
 338                         opt, tmp, list)
 339                 talloc_free(opt);
 340         list_init(&handler->unresolved_boot_options);
 341
 342         /* drop all devices */
 343         for (i = 0; i < handler->n_devices; i++) {
 344                 discover_server_notify_device_remove(handler->server,
 345                                 handler->devices[i]->device);
 346                 ramdisk = handler->devices[i]->ramdisk;
 347                 talloc_free(handler->devices[i]);
 348                 talloc_free(ramdisk);
 349         }
 350
 351         talloc_free(handler->devices);
 352         handler->devices = NULL;
 353         handler->n_devices = 0;
 354         talloc_free(handler->ramdisks);
 355         handler->ramdisks = NULL;
 356         handler->n_ramdisks = 0;
 357
 358         device_handler_reinit_sources(handler);
 359 }
 360
 361 void device_handler_remove(struct device_handler *handler,
 362                 struct discover_device *device)
 363 {
 364         struct discover_boot_option *opt, *tmp;
 365         unsigned int i;
 366
 367         list_for_each_entry_safe(&device->boot_options, opt, tmp, list) {
 368                 if (opt == handler->default_boot_option) {
 369                         pb_log("Default option %s cancelled since device removed",
 370                                         opt->option->name);
 371                         device_handler_cancel_default(handler);
 372                         break;
 373                 }
 374         }
 375
 376         for (i = 0; i < handler->n_devices; i++)
 377                 if (handler->devices[i] == device)
 378                         break;
 379
 380         if (i == handler->n_devices) {
 381                 talloc_free(device);
 382                 return;
 383         }
 384
 385         /* Free any unresolved options, as they're currently allocated
 386          * against the handler */
 387         list_for_each_entry_safe(&handler->unresolved_boot_options,
 388                         opt, tmp, list) {
 389                 if (opt->device != device)
 390                         continue;
 391                 list_remove(&opt->list);
 392                 talloc_free(opt);
 393         }
 394
 395         /* if this is a network device, we have to unregister it from the
 396          * network code */
 397         if (device->device->type == DEVICE_TYPE_NETWORK)
 398                 network_unregister_device(handler->network, device);
 399
 400         handler->n_devices--;
 401         memmove(&handler->devices[i], &handler->devices[i + 1],
 402                 (handler->n_devices - i) * sizeof(handler->devices[0]));
 403         handler->devices = talloc_realloc(handler, handler->devices,
 404                 struct discover_device *, handler->n_devices);
 405
 406         if (device->notified)
 407                 discover_server_notify_device_remove(handler->server,
 408                                                         device->device);
 409
 410         talloc_free(device);
 411 }
 412
 413 void device_handler_status(struct device_handler *handler,
 414                 struct status *status)
 415 {
 416         discover_server_notify_boot_status(handler->server, status);
 417 }
 418
 419 static void _device_handler_vstatus(struct device_handler *handler,
 420                 enum status_type type, const char *fmt, va_list ap)
 421 {
 422         struct status status;
 423
 424         status.type = type;
 425         status.message = talloc_vasprintf(handler, fmt, ap);
 426
 427         device_handler_status(handler, &status);
 428
 429         talloc_free(status.message);
 430 }
 431
 432 void device_handler_status_info(struct device_handler *handler,
 433                 const char *fmt, ...)
 434 {
 435         va_list ap;
 436
 437         va_start(ap, fmt);
 438         _device_handler_vstatus(handler, STATUS_INFO, fmt, ap);
 439         va_end(ap);
 440 }
 441
 442 void device_handler_status_err(struct device_handler *handler,
 443                 const char *fmt, ...)
 444 {
 445         va_list ap;
 446
 447         va_start(ap, fmt);
 448         _device_handler_vstatus(handler, STATUS_ERROR, fmt, ap);
 449         va_end(ap);
 450 }
 451
 452 static void device_handler_boot_status_cb(void *arg, struct status *status)
 453 {
 454         device_handler_status(arg, status);
 455 }
 456
 457 static void countdown_status(struct device_handler *handler,
 458                 struct discover_boot_option *opt, unsigned int sec)
 459 {
 460         struct status status;
 461
 462         status.type = STATUS_INFO;
 463         status.message = talloc_asprintf(handler,
 464                         _("Booting in %d sec: %s"), sec, opt->option->name);
 465
 466         device_handler_status(handler, &status);
 467
 468         talloc_free(status.message);
 469 }
 470
 471 static int default_timeout(void *arg)
 472 {
 473         struct device_handler *handler = arg;
 474         struct discover_boot_option *opt;
 475
 476         if (!handler->default_boot_option)
 477                 return 0;
 478
 479         if (handler->pending_boot)
 480                 return 0;
 481
 482         opt = handler->default_boot_option;
 483
 484         if (handler->sec_to_boot) {
 485                 countdown_status(handler, opt, handler->sec_to_boot);
 486                 handler->sec_to_boot--;
 487                 handler->timeout_waiter = waiter_register_timeout(
 488                                                 handler->waitset, 1000,
 489                                                 default_timeout, handler);
 490                 return 0;
 491         }
 492
 493         handler->timeout_waiter = NULL;
 494
 495         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 496
 497         platform_pre_boot();
 498
 499         handler->pending_boot = boot(handler, handler->default_boot_option,
 500                         NULL, handler->dry_run, device_handler_boot_status_cb,
 501                         handler);
 502         handler->pending_boot_is_default = true;
 503         return 0;
 504 }
 505
 506 struct {
 507         enum ipmi_bootdev       ipmi_type;
 508         enum device_type        device_type;
 509 } device_type_map[] = {
 510         { IPMI_BOOTDEV_NETWORK, DEVICE_TYPE_NETWORK },
 511         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_DISK },
 512         { IPMI_BOOTDEV_DISK, DEVICE_TYPE_USB },
 513         { IPMI_BOOTDEV_CDROM, DEVICE_TYPE_OPTICAL },
 514 };
 515
 516 static bool ipmi_device_type_matches(enum ipmi_bootdev ipmi_type,
 517                 enum device_type device_type)
 518 {
 519         unsigned int i;
 520
 521         for (i = 0; i < ARRAY_SIZE(device_type_map); i++) {
 522                 if (device_type_map[i].device_type == device_type)
 523                         return device_type_map[i].ipmi_type == ipmi_type;
 524         }
 525
 526         return false;
 527 }
 528
 529 static int autoboot_option_priority(const struct config *config,
 530                                 struct discover_boot_option *opt)
 531 {
 532         enum device_type type = opt->device->device->type;
 533         const char *uuid = opt->device->uuid;
 534         struct autoboot_option *auto_opt;
 535         unsigned int i;
 536
 537         for (i = 0; i < config->n_autoboot_opts; i++) {
 538                 auto_opt = &config->autoboot_opts[i];
 539                 if (auto_opt->boot_type == BOOT_DEVICE_UUID)
 540                         if (!strcmp(auto_opt->uuid, uuid))
 541                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 542
 543                 if (auto_opt->boot_type == BOOT_DEVICE_TYPE)
 544                         if (auto_opt->type == type ||
 545                             auto_opt->type == DEVICE_TYPE_ANY)
 546                                 return DEFAULT_PRIORITY_LOCAL_FIRST + i;
 547         }
 548
 549         return -1;
 550 }
 551
 552 /*
 553  * We have different priorities to resolve conflicts between boot options that
 554  * report to be the default for their device. This function assigns a priority
 555  * for these options.
 556  */
 557 static enum default_priority default_option_priority(
 558                 struct discover_boot_option *opt)
 559 {
 560         const struct config *config;
 561
 562         config = config_get();
 563
 564         /* We give highest priority to IPMI-configured boot options. If
 565          * we have an IPMI bootdev configuration set, then we don't allow
 566          * any other defaults */
 567         if (config->ipmi_bootdev) {
 568                 bool ipmi_match = ipmi_device_type_matches(config->ipmi_bootdev,
 569                                 opt->device->device->type);
 570                 if (ipmi_match)
 571                         return DEFAULT_PRIORITY_REMOTE;
 572
 573                 pb_debug("handler: disabled default priority due to "
 574                                 "non-matching IPMI type %x\n",
 575                                 config->ipmi_bootdev);
 576                 return DEFAULT_PRIORITY_DISABLED;
 577         }
 578
 579         /* Next, try to match the option against the user-defined autoboot
 580          * options, either by device UUID or type. */
 581         if (config->n_autoboot_opts) {
 582                 int boot_match = autoboot_option_priority(config, opt);
 583                 if (boot_match > 0)
 584                         return boot_match;
 585         }
 586
 587         /* If the option didn't match any entry in the array, it is disabled */
 588         pb_debug("handler: disabled default priority due to "
 589                         "non-matching UUID or type\n");
 590         return DEFAULT_PRIORITY_DISABLED;
 591 }
 592
 593 static void set_default(struct device_handler *handler,
 594                 struct discover_boot_option *opt)
 595 {
 596         enum default_priority cur_prio, new_prio;
 597
 598         if (!handler->autoboot_enabled)
 599                 return;
 600
 601         pb_debug("handler: new default option: %s\n", opt->option->id);
 602
 603         new_prio = default_option_priority(opt);
 604
 605         /* Anything outside our range prevents a default boot */
 606         if (new_prio >= DEFAULT_PRIORITY_DISABLED)
 607                 return;
 608
 609         pb_debug("handler: calculated priority %d\n", new_prio);
 610
 611         /* Resolve any conflicts: if we have a new default option, it only
 612          * replaces the current if it has a higher priority. */
 613         if (handler->default_boot_option) {
 614
 615                 cur_prio = handler->default_boot_option_priority;
 616
 617                 if (new_prio < cur_prio) {
 618                         pb_log("handler: new prio %d beats "
 619                                         "old prio %d for %s\n",
 620                                         new_prio, cur_prio,
 621                                         handler->default_boot_option
 622                                                 ->option->id);
 623                         handler->default_boot_option = opt;
 624                         handler->default_boot_option_priority = new_prio;
 625                         /* extend the timeout a little, so the user sees some
 626                          * indication of the change */
 627                         handler->sec_to_boot += 2;
 628                 }
 629
 630                 return;
 631         }
 632
 633         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
 634         handler->default_boot_option = opt;
 635         handler->default_boot_option_priority = new_prio;
 636
 637         pb_log("handler: boot option %s set as default, timeout %u sec.\n",
 638                opt->option->id, handler->sec_to_boot);
 639
 640         default_timeout(handler);
 641 }
 642
 643 static bool resource_is_resolved(struct resource *res)
 644 {
 645         return !res || res->resolved;
 646 }
 647
 648 /* We only use this in an assert, which will disappear if we're compiling
 649  * with NDEBUG, so we need the 'used' attribute for these builds */
 650 static bool __attribute__((used)) boot_option_is_resolved(
 651                 struct discover_boot_option *opt)
 652 {
 653         return resource_is_resolved(opt->boot_image) &&
 654                 resource_is_resolved(opt->initrd) &&
 655                 resource_is_resolved(opt->dtb) &&
 656                 resource_is_resolved(opt->args_sig_file) &&
 657                 resource_is_resolved(opt->icon);
 658 }
 659
 660 static bool resource_resolve(struct resource *res, const char *name,
 661                 struct discover_boot_option *opt,
 662                 struct device_handler *handler)
 663 {
 664         struct parser *parser = opt->source;
 665
 666         if (resource_is_resolved(res))
 667                 return true;
 668
 669         pb_debug("Attempting to resolve resource %s->%s with parser %s\n",
 670                         opt->option->id, name, parser->name);
 671         parser->resolve_resource(handler, res);
 672
 673         return res->resolved;
 674 }
 675
 676 static bool boot_option_resolve(struct discover_boot_option *opt,
 677                 struct device_handler *handler)
 678 {
 679         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
 680                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
 681                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
 682                 resource_resolve(opt->args_sig_file, "args_sig_file", opt,
 683                         handler) &&
 684                 resource_resolve(opt->icon, "icon", opt, handler);
 685 }
 686
 687 static void boot_option_finalise(struct device_handler *handler,
 688                 struct discover_boot_option *opt)
 689 {
 690         assert(boot_option_is_resolved(opt));
 691
 692         /* check that the parsers haven't set any of the final data */
 693         assert(!opt->option->boot_image_file);
 694         assert(!opt->option->initrd_file);
 695         assert(!opt->option->dtb_file);
 696         assert(!opt->option->icon_file);
 697         assert(!opt->option->device_id);
 698         assert(!opt->option->args_sig_file);
 699
 700         if (opt->boot_image)
 701                 opt->option->boot_image_file = opt->boot_image->url->full;
 702         if (opt->initrd)
 703                 opt->option->initrd_file = opt->initrd->url->full;
 704         if (opt->dtb)
 705                 opt->option->dtb_file = opt->dtb->url->full;
 706         if (opt->icon)
 707                 opt->option->icon_file = opt->icon->url->full;
 708         if (opt->args_sig_file)
 709                 opt->option->args_sig_file = opt->args_sig_file->url->full;
 710
 711         opt->option->device_id = opt->device->device->id;
 712
 713         if (opt->option->is_default)
 714                 set_default(handler, opt);
 715 }
 716
 717 static void notify_boot_option(struct device_handler *handler,
 718                 struct discover_boot_option *opt)
 719 {
 720         struct discover_device *dev = opt->device;
 721
 722         if (!dev->notified)
 723                 discover_server_notify_device_add(handler->server,
 724                                                   opt->device->device);
 725         dev->notified = true;
 726         discover_server_notify_boot_option_add(handler->server, opt->option);
 727 }
 728
 729 static void process_boot_option_queue(struct device_handler *handler)
 730 {
 731         struct discover_boot_option *opt, *tmp;
 732
 733         list_for_each_entry_safe(&handler->unresolved_boot_options,
 734                         opt, tmp, list) {
 735
 736                 pb_debug("queue: attempting resolution for %s\n",
 737                                 opt->option->id);
 738
 739                 if (!boot_option_resolve(opt, handler))
 740                         continue;
 741
 742                 pb_debug("\tresolved!\n");
 743
 744                 list_remove(&opt->list);
 745                 list_add_tail(&opt->device->boot_options, &opt->list);
 746                 talloc_steal(opt->device, opt);
 747                 boot_option_finalise(handler, opt);
 748                 notify_boot_option(handler, opt);
 749         }
 750 }
 751
 752 struct discover_context *device_handler_discover_context_create(
 753                 struct device_handler *handler,
 754                 struct discover_device *device)
 755 {
 756         struct discover_context *ctx;
 757
 758         ctx = talloc_zero(handler, struct discover_context);
 759         ctx->device = device;
 760         ctx->network = handler->network;
 761         list_init(&ctx->boot_options);
 762
 763         return ctx;
 764 }
 765
 766 void device_handler_add_device(struct device_handler *handler,
 767                 struct discover_device *device)
 768 {
 769         handler->n_devices++;
 770         handler->devices = talloc_realloc(handler, handler->devices,
 771                                 struct discover_device *, handler->n_devices);
 772         handler->devices[handler->n_devices - 1] = device;
 773
 774         if (device->device->type == DEVICE_TYPE_NETWORK)
 775                 network_register_device(handler->network, device);
 776 }
 777
 778 void device_handler_add_ramdisk(struct device_handler *handler,
 779                 const char *path)
 780 {
 781         struct ramdisk_device *dev;
 782         unsigned int i;
 783
 784         if (!path)
 785                 return;
 786
 787         for (i = 0; i < handler->n_ramdisks; i++)
 788                 if (!strcmp(handler->ramdisks[i]->path, path))
 789                         return;
 790
 791         dev = talloc_zero(handler, struct ramdisk_device);
 792         if (!dev) {
 793                 pb_log("Failed to allocate memory to track %s\n", path);
 794                 return;
 795         }
 796
 797         dev->path = talloc_strdup(handler, path);
 798
 799         handler->ramdisks = talloc_realloc(handler, handler->ramdisks,
 800                                 struct ramdisk_device *,
 801                                 handler->n_ramdisks + 1);
 802         if (!handler->ramdisks) {
 803                 pb_log("Failed to reallocate memory"
 804                        "- ramdisk tracking inconsistent!\n");
 805                 return;
 806         }
 807
 808         handler->ramdisks[i] = dev;
 809         i = handler->n_ramdisks++;
 810 }
 811
 812 struct ramdisk_device *device_handler_get_ramdisk(
 813                 struct device_handler *handler)
 814 {
 815         unsigned int i;
 816         char *name;
 817         dev_t id;
 818
 819         /* Check if free ramdisk exists */
 820         for (i = 0; i < handler->n_ramdisks; i++)
 821                 if (!handler->ramdisks[i]->snapshot &&
 822                     !handler->ramdisks[i]->origin &&
 823                     !handler->ramdisks[i]->base)
 824                         return handler->ramdisks[i];
 825
 826         /* Otherwise create a new one */
 827         name = talloc_asprintf(handler, "/dev/ram%d",
 828                         handler->n_ramdisks);
 829         if (!name) {
 830                 pb_debug("Failed to allocate memory to name /dev/ram%d",
 831                         handler->n_ramdisks);
 832                 return NULL;
 833         }
 834
 835         id = makedev(1, handler->n_ramdisks);
 836         if (mknod(name, S_IFBLK, id)) {
 837                 if (errno == EEXIST) {
 838                         /* We haven't yet received updates for existing
 839                          * ramdisks - add and use this one */
 840                         pb_debug("Using untracked ramdisk %s\n", name);
 841                 } else {
 842                         pb_log("Failed to create new ramdisk %s: %s\n",
 843                                name, strerror(errno));
 844                         return NULL;
 845                 }
 846         }
 847         device_handler_add_ramdisk(handler, name);
 848         talloc_free(name);
 849
 850         return handler->ramdisks[i];
 851 }
 852
 853 void device_handler_release_ramdisk(struct discover_device *device)
 854 {
 855         struct ramdisk_device *ramdisk = device->ramdisk;
 856
 857         talloc_free(ramdisk->snapshot);
 858         talloc_free(ramdisk->origin);
 859         talloc_free(ramdisk->base);
 860
 861         ramdisk->snapshot = ramdisk->origin = ramdisk->base = NULL;
 862         ramdisk->sectors = 0;
 863
 864         device->ramdisk = NULL;
 865 }
 866
 867 /* Start discovery on a hotplugged device. The device will be in our devices
 868  * array, but has only just been initialised by the hotplug source.
 869  */
 870 int device_handler_discover(struct device_handler *handler,
 871                 struct discover_device *dev)
 872 {
 873         struct discover_context *ctx;
 874         int rc;
 875
 876         /*
 877          * TRANSLATORS: this string will be passed the type and identifier
 878          * of the device. For example, the first parameter could be "Disk",
 879          * (which will be translated accordingly) and the second a Linux device
 880          * identifier like 'sda1' (which will not be translated)
 881          */
 882         device_handler_status_info(handler, _("Processing %s device %s"),
 883                                 device_type_display_name(dev->device->type),
 884                                 dev->device->id);
 885
 886         process_boot_option_queue(handler);
 887
 888         /* create our context */
 889         ctx = device_handler_discover_context_create(handler, dev);
 890
 891         rc = mount_device(dev);
 892         if (rc)
 893                 goto out;
 894
 895         /* add this device to our system info */
 896         system_info_register_blockdev(dev->device->id, dev->uuid,
 897                         dev->mount_path);
 898
 899         /* run the parsers. This will populate the ctx's boot_option list. */
 900         iterate_parsers(ctx);
 901
 902         /* add discovered stuff to the handler */
 903         device_handler_discover_context_commit(handler, ctx);
 904
 905 out:
 906         /*
 907          * TRANSLATORS: the format specifier in this string is a Linux
 908          * device identifier, like 'sda1'
 909          */
 910         device_handler_status_info(handler, _("Processing %s complete"),
 911                                 dev->device->id);
 912
 913         talloc_unlink(handler, ctx);
 914
 915         return 0;
 916 }
 917
 918 /* Incoming dhcp event */
 919 int device_handler_dhcp(struct device_handler *handler,
 920                 struct discover_device *dev, struct event *event)
 921 {
 922         struct discover_context *ctx;
 923
 924         /*
 925          * TRANSLATORS: this format specifier will be the name of a network
 926          * device, like 'eth0'.
 927          */
 928         device_handler_status_info(handler, _("Processing dhcp event on %s"),
 929                                 dev->device->id);
 930
 931         /* create our context */
 932         ctx = device_handler_discover_context_create(handler, dev);
 933         talloc_steal(ctx, event);
 934         ctx->event = event;
 935
 936         iterate_parsers(ctx);
 937
 938         device_handler_discover_context_commit(handler, ctx);
 939
 940         /*
 941          * TRANSLATORS: this format specifier will be the name of a network
 942          * device, like 'eth0'.
 943          */
 944         device_handler_status_info(handler, _("Processing %s complete"),
 945                                 dev->device->id);
 946
 947         talloc_unlink(handler, ctx);
 948
 949         return 0;
 950 }
 951
 952 static struct discover_boot_option *find_boot_option_by_id(
 953                 struct device_handler *handler, const char *id)
 954 {
 955         unsigned int i;
 956
 957         for (i = 0; i < handler->n_devices; i++) {
 958                 struct discover_device *dev = handler->devices[i];
 959                 struct discover_boot_option *opt;
 960
 961                 list_for_each_entry(&dev->boot_options, opt, list)
 962                         if (!strcmp(opt->option->id, id))
 963                                 return opt;
 964         }
 965
 966         return NULL;
 967 }
 968
 969 void device_handler_boot(struct device_handler *handler,
 970                 struct boot_command *cmd)
 971 {
 972         struct discover_boot_option *opt = NULL;
 973
 974         if (cmd->option_id && strlen(cmd->option_id))
 975                 opt = find_boot_option_by_id(handler, cmd->option_id);
 976
 977         if (handler->pending_boot)
 978                 boot_cancel(handler->pending_boot);
 979
 980         platform_pre_boot();
 981
 982         handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
 983                         device_handler_boot_status_cb, handler);
 984         handler->pending_boot_is_default = false;
 985 }
 986
 987 void device_handler_cancel_default(struct device_handler *handler)
 988 {
 989         if (handler->timeout_waiter)
 990                 waiter_remove(handler->timeout_waiter);
 991
 992         handler->timeout_waiter = NULL;
 993         handler->autoboot_enabled = false;
 994
 995         /* we only send status if we had a default boot option queued */
 996         if (!handler->default_boot_option)
 997                 return;
 998
 999         pb_log("Cancelling default boot option\n");
1000
1001         if (handler->pending_boot && handler->pending_boot_is_default) {
1002                 boot_cancel(handler->pending_boot);
1003                 handler->pending_boot = NULL;
1004                 handler->pending_boot_is_default = false;
1005         }
1006
1007         handler->default_boot_option = NULL;
1008
1009         device_handler_status_info(handler, _("Default boot cancelled"));
1010 }
1011
1012 void device_handler_update_config(struct device_handler *handler,
1013                 struct config *config)
1014 {
1015         int rc;
1016
1017         rc = config_set(config);
1018         if (rc)
1019                 return;
1020
1021         discover_server_notify_config(handler->server, config);
1022         device_handler_update_lang(config->lang);
1023         device_handler_reinit(handler);
1024 }
1025
1026 static char *device_from_addr(void *ctx, struct pb_url *url)
1027 {
1028         char *ipaddr, *buf, *tok, *dev = NULL;
1029         const char *delim = " ";
1030         struct sockaddr_in *ip;
1031         struct sockaddr_in si;
1032         struct addrinfo *res;
1033         struct process *p;
1034         int rc;
1035
1036         /* Note: IPv4 only */
1037         rc = inet_pton(AF_INET, url->host, &(si.sin_addr));
1038         if (rc > 0) {
1039                 ipaddr = url->host;
1040         } else {
1041                 /* need to turn hostname into a valid IP */
1042                 rc = getaddrinfo(url->host, NULL, NULL, &res);
1043                 if (rc) {
1044                         pb_debug("%s: Invalid URL\n",__func__);
1045                         return NULL;
1046                 }
1047                 ipaddr = talloc_array(ctx,char,INET_ADDRSTRLEN);
1048                 ip = (struct sockaddr_in *) res->ai_addr;
1049                 inet_ntop(AF_INET, &(ip->sin_addr), ipaddr, INET_ADDRSTRLEN);
1050                 freeaddrinfo(res);
1051         }
1052
1053         const char *argv[] = {
1054                 pb_system_apps.ip,
1055                 "route", "show", "to", "match",
1056                 ipaddr,
1057                 NULL
1058         };
1059
1060         p = process_create(ctx);
1061
1062         p->path = pb_system_apps.ip;
1063         p->argv = argv;
1064         p->keep_stdout = true;
1065
1066         rc = process_run_sync(p);
1067
1068         if (rc || p->exit_status) {
1069                 /* ip has complained for some reason; most likely
1070                  * there is no route to the host - bail out */
1071                 pb_debug("%s: `ip` returns non-zero exit status\n", __func__);
1072                 pb_debug("ip buf: %s\n", p->stdout_buf);
1073                 process_release(p);
1074                 return NULL;
1075         }
1076
1077         buf = p->stdout_buf;
1078         /* If a route is found, ip-route output will be of the form
1079          * "... dev DEVNAME ... " */
1080         tok = strtok(buf, delim);
1081         while (tok) {
1082                 if (!strcmp(tok, "dev")) {
1083                         tok = strtok(NULL, delim);
1084                         dev = talloc_strdup(ctx, tok);
1085                         break;
1086                 }
1087                 tok = strtok(NULL, delim);
1088         }
1089
1090         process_release(p);
1091         if (dev)
1092                 pb_debug("%s: Found interface '%s'\n", __func__,dev);
1093         return dev;
1094 }
1095
1096 void device_handler_process_url(struct device_handler *handler,
1097                 const char *url, const char *mac, const char *ip)
1098 {
1099         struct discover_context *ctx;
1100         struct discover_device *dev;
1101         struct pb_url *pb_url;
1102         struct event *event;
1103         struct param *param;
1104
1105         if (!handler->network) {
1106                 device_handler_status_err(handler, _("No network configured"));
1107                 return;
1108         }
1109
1110         event = talloc(handler, struct event);
1111         event->type = EVENT_TYPE_USER;
1112         event->action = EVENT_ACTION_URL;
1113
1114         if (url[strlen(url) - 1] == '/') {
1115                 event->params = talloc_array(event, struct param, 3);
1116                 param = &event->params[0];
1117                 param->name = talloc_strdup(event, "pxepathprefix");
1118                 param->value = talloc_strdup(event, url);
1119                 param = &event->params[1];
1120                 param->name = talloc_strdup(event, "mac");
1121                 param->value = talloc_strdup(event, mac);
1122                 param = &event->params[2];
1123                 param->name = talloc_strdup(event, "ip");
1124                 param->value = talloc_strdup(event, ip);
1125                 event->n_params = 3;
1126         } else {
1127                 event->params = talloc_array(event, struct param, 1);
1128                 param = &event->params[0];
1129                 param->name = talloc_strdup(event, "pxeconffile");
1130                 param->value = talloc_strdup(event, url);
1131                 event->n_params = 1;
1132         }
1133
1134         pb_url = pb_url_parse(event, event->params->value);
1135         if (!pb_url || (pb_url->scheme != pb_url_file && !pb_url->host)) {
1136                 device_handler_status_err(handler, _("Invalid config URL!"));
1137                 return;
1138         }
1139
1140         if (pb_url->scheme == pb_url_file)
1141                 event->device = talloc_asprintf(event, "local");
1142         else
1143                 event->device = device_from_addr(event, pb_url);
1144
1145         if (!event->device) {
1146                 device_handler_status_err(handler,
1147                                         _("Unable to route to host %s"),
1148                                         pb_url->host);
1149                 return;
1150         }
1151
1152         dev = discover_device_create(handler, mac, event->device);
1153         if (pb_url->scheme == pb_url_file)
1154                 dev->device->type = DEVICE_TYPE_ANY;
1155         ctx = device_handler_discover_context_create(handler, dev);
1156         talloc_steal(ctx, event);
1157         ctx->event = event;
1158
1159         iterate_parsers(ctx);
1160
1161         device_handler_discover_context_commit(handler, ctx);
1162
1163         talloc_unlink(handler, ctx);
1164 }
1165
1166 #ifndef PETITBOOT_TEST
1167
1168 /**
1169  * context_commit - Commit a temporary discovery context to the handler,
1170  * and notify the clients about any new options / devices
1171  */
1172 void device_handler_discover_context_commit(struct device_handler *handler,
1173                 struct discover_context *ctx)
1174 {
1175         struct discover_device *dev = ctx->device;
1176         struct discover_boot_option *opt, *tmp;
1177
1178         if (!device_lookup_by_uuid(handler, dev->uuid))
1179                 device_handler_add_device(handler, dev);
1180
1181         /* move boot options from the context to the device */
1182         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
1183                 list_remove(&opt->list);
1184
1185                 /* All boot options need at least a kernel image */
1186                 if (!opt->boot_image || !opt->boot_image->url) {
1187                         pb_log("boot option %s is missing boot image, ignoring\n",
1188                                 opt->option->id);
1189                         talloc_free(opt);
1190                         continue;
1191                 }
1192
1193                 if (boot_option_resolve(opt, handler)) {
1194                         pb_log("boot option %s is resolved, "
1195                                         "sending to clients\n",
1196                                         opt->option->id);
1197                         list_add_tail(&dev->boot_options, &opt->list);
1198                         talloc_steal(dev, opt);
1199                         boot_option_finalise(handler, opt);
1200                         notify_boot_option(handler, opt);
1201                 } else {
1202                         if (!opt->source->resolve_resource) {
1203                                 pb_log("parser %s gave us an unresolved "
1204                                         "resource (%s), but no way to "
1205                                         "resolve it\n",
1206                                         opt->source->name, opt->option->id);
1207                                 talloc_free(opt);
1208                         } else {
1209                                 pb_log("boot option %s is unresolved, "
1210                                                 "adding to queue\n",
1211                                                 opt->option->id);
1212                                 list_add(&handler->unresolved_boot_options,
1213                                                 &opt->list);
1214                                 talloc_steal(handler, opt);
1215                         }
1216                 }
1217         }
1218 }
1219
1220 static void device_handler_update_lang(const char *lang)
1221 {
1222         const char *cur_lang;
1223
1224         if (!lang)
1225                 return;
1226
1227         cur_lang = setlocale(LC_ALL, NULL);
1228         if (cur_lang && !strcmp(cur_lang, lang))
1229                 return;
1230
1231         setlocale(LC_ALL, lang);
1232 }
1233
1234 static int device_handler_init_sources(struct device_handler *handler)
1235 {
1236         /* init our device sources: udev, network and user events */
1237         handler->udev = udev_init(handler, handler->waitset);
1238         if (!handler->udev)
1239                 return -1;
1240
1241         handler->network = network_init(handler, handler->waitset,
1242                         handler->dry_run);
1243         if (!handler->network)
1244                 return -1;
1245
1246         handler->user_event = user_event_init(handler, handler->waitset);
1247         if (!handler->user_event)
1248                 return -1;
1249
1250         return 0;
1251 }
1252
1253 static void device_handler_reinit_sources(struct device_handler *handler)
1254 {
1255         /* if we haven't initialised sources previously (becuase we started in
1256          * safe mode), then init once here. */
1257         if (!(handler->udev || handler->network || handler->user_event)) {
1258                 device_handler_init_sources(handler);
1259                 return;
1260         }
1261
1262         udev_reinit(handler->udev);
1263
1264         network_shutdown(handler->network);
1265         handler->network = network_init(handler, handler->waitset,
1266                         handler->dry_run);
1267 }
1268
1269 static inline const char *get_device_path(struct discover_device *dev)
1270 {
1271         return dev->ramdisk ? dev->ramdisk->snapshot : dev->device_path;
1272 }
1273
1274 static char *check_subvols(struct discover_device *dev)
1275 {
1276         const char *fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1277         struct stat sb;
1278         char *path;
1279         int rc;
1280
1281         if (strncmp(fstype, "btrfs", strlen("btrfs")))
1282                 return dev->mount_path;
1283
1284         /* On btrfs a device's root may be under a subvolume path */
1285         path = join_paths(dev, dev->mount_path, "@");
1286         rc = stat(path, &sb);
1287         if (!rc && S_ISDIR(sb.st_mode)) {
1288                 pb_debug("Using '%s' for btrfs root path\n", path);
1289                 return path;
1290         }
1291
1292         talloc_free(path);
1293         return dev->mount_path;
1294 }
1295
1296 static bool check_existing_mount(struct discover_device *dev)
1297 {
1298         struct stat devstat, mntstat;
1299         const char *device_path;
1300         struct mntent *mnt;
1301         FILE *fp;
1302         int rc;
1303
1304         device_path = get_device_path(dev);
1305
1306         rc = stat(device_path, &devstat);
1307         if (rc) {
1308                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
1309                 return false;
1310         }
1311
1312         if (!S_ISBLK(devstat.st_mode)) {
1313                 pb_debug("%s: %s isn't a block device?\n", __func__,
1314                                 dev->device_path);
1315                 return false;
1316         }
1317
1318         fp = fopen("/proc/self/mounts", "r");
1319
1320         for (;;) {
1321                 mnt = getmntent(fp);
1322                 if (!mnt)
1323                         break;
1324
1325                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
1326                         continue;
1327
1328                 rc = stat(mnt->mnt_fsname, &mntstat);
1329                 if (rc)
1330                         continue;
1331
1332                 if (!S_ISBLK(mntstat.st_mode))
1333                         continue;
1334
1335                 if (mntstat.st_rdev == devstat.st_rdev) {
1336                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
1337                         dev->root_path = check_subvols(dev);
1338                         dev->mounted_rw = !!hasmntopt(mnt, "rw");
1339                         dev->mounted = true;
1340                         dev->unmount = false;
1341
1342                         pb_debug("%s: %s is already mounted (r%c) at %s\n",
1343                                         __func__, dev->device_path,
1344                                         dev->mounted_rw ? 'w' : 'o',
1345                                         mnt->mnt_dir);
1346                         break;
1347                 }
1348         }
1349
1350         fclose(fp);
1351
1352         return mnt != NULL;
1353 }
1354
1355 /*
1356  * Attempt to mount a filesystem safely, while handling certain filesytem-
1357  * specific options
1358  */
1359 static int try_mount(const char *device_path, const char *mount_path,
1360                              const char *fstype, unsigned long flags,
1361                              bool have_snapshot)
1362 {
1363         const char *fs, *safe_opts;
1364         int rc;
1365
1366         /* Mount ext3 as ext4 instead so 'norecovery' can be used */
1367         if (strncmp(fstype, "ext3", strlen("ext3")) == 0) {
1368                 pb_debug("Mounting ext3 filesystem as ext4\n");
1369                 fs = "ext4";
1370         } else
1371                 fs = fstype;
1372
1373         if (strncmp(fs, "xfs", strlen("xfs")) == 0 ||
1374             strncmp(fs, "ext4", strlen("ext4")) == 0)
1375                 safe_opts = "norecovery";
1376         else
1377                 safe_opts = NULL;
1378
1379         errno = 0;
1380         /* If no snapshot is available don't attempt recovery */
1381         if (!have_snapshot)
1382                 return mount(device_path, mount_path, fs, flags, safe_opts);
1383
1384         rc = mount(device_path, mount_path, fs, flags, NULL);
1385
1386         if (!rc)
1387                 return rc;
1388
1389         /* Mounting failed; some filesystems will fail to mount if a recovery
1390          * journal exists (eg. cross-endian XFS), so try again with norecovery
1391          * where that option is available.
1392          * If mounting read-write just return the error as norecovery is not a
1393          * valid option */
1394         if ((flags & MS_RDONLY) != MS_RDONLY || !safe_opts)
1395                 return rc;
1396
1397         errno = 0;
1398         return mount(device_path, mount_path, fs, flags, safe_opts);
1399 }
1400
1401 static int mount_device(struct discover_device *dev)
1402 {
1403         const char *fstype, *device_path;
1404         int rc;
1405
1406         if (!dev->device_path)
1407                 return -1;
1408
1409         if (dev->mounted)
1410                 return 0;
1411
1412         if (check_existing_mount(dev))
1413                 return 0;
1414
1415         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1416         if (!fstype)
1417                 return 0;
1418
1419         dev->mount_path = join_paths(dev, mount_base(),
1420                                         dev->device_path);
1421
1422         if (pb_mkdir_recursive(dev->mount_path)) {
1423                 pb_log("couldn't create mount directory %s: %s\n",
1424                                 dev->mount_path, strerror(errno));
1425                 goto err_free;
1426         }
1427
1428         device_path = get_device_path(dev);
1429
1430         pb_log("mounting device %s read-only\n", dev->device_path);
1431         rc = try_mount(device_path, dev->mount_path, fstype,
1432                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1433
1434         if (!rc) {
1435                 dev->mounted = true;
1436                 dev->mounted_rw = false;
1437                 dev->unmount = true;
1438                 dev->root_path = check_subvols(dev);
1439                 return 0;
1440         }
1441
1442         pb_log("couldn't mount device %s: mount failed: %s\n",
1443                         device_path, strerror(errno));
1444
1445         /* If mount fails clean up any snapshot */
1446         devmapper_destroy_snapshot(dev);
1447
1448         pb_rmdir_recursive(mount_base(), dev->mount_path);
1449 err_free:
1450         talloc_free(dev->mount_path);
1451         dev->mount_path = NULL;
1452         return -1;
1453 }
1454
1455 static int umount_device(struct discover_device *dev)
1456 {
1457         const char *device_path;
1458         int rc;
1459
1460         if (!dev->mounted || !dev->unmount)
1461                 return 0;
1462
1463         device_path = get_device_path(dev);
1464
1465         pb_log("unmounting device %s\n", device_path);
1466         rc = umount(dev->mount_path);
1467         if (rc)
1468                 return -1;
1469
1470         dev->mounted = false;
1471         devmapper_destroy_snapshot(dev);
1472
1473         pb_rmdir_recursive(mount_base(), dev->mount_path);
1474
1475         talloc_free(dev->mount_path);
1476         dev->mount_path = NULL;
1477         dev->root_path = NULL;
1478
1479         return 0;
1480 }
1481
1482 int device_request_write(struct discover_device *dev, bool *release)
1483 {
1484         const char *fstype, *device_path;
1485         const struct config *config;
1486         int rc;
1487
1488         *release = false;
1489
1490         config = config_get();
1491         if (!config->allow_writes)
1492                 return -1;
1493
1494         if (!dev->mounted)
1495                 return -1;
1496
1497         if (dev->mounted_rw)
1498                 return 0;
1499
1500         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1501
1502         device_path = get_device_path(dev);
1503
1504         pb_log("remounting device %s read-write\n", device_path);
1505
1506         rc = umount(dev->mount_path);
1507         if (rc) {
1508                 pb_log("Failed to unmount %s: %s\n",
1509                        dev->mount_path, strerror(errno));
1510                 return -1;
1511         }
1512
1513         rc = try_mount(device_path, dev->mount_path, fstype,
1514                        MS_SILENT, dev->ramdisk);
1515         if (rc)
1516                 goto mount_ro;
1517
1518         dev->mounted_rw = true;
1519         *release = true;
1520         return 0;
1521
1522 mount_ro:
1523         pb_log("Unable to remount device %s read-write: %s\n",
1524                device_path, strerror(errno));
1525         rc = try_mount(device_path, dev->mount_path, fstype,
1526                        MS_RDONLY | MS_SILENT, dev->ramdisk);
1527         if (rc)
1528                 pb_log("Unable to recover mount for %s: %s\n",
1529                        device_path, strerror(errno));
1530         return -1;
1531 }
1532
1533 void device_release_write(struct discover_device *dev, bool release)
1534 {
1535         const char *fstype, *device_path;
1536
1537         if (!release)
1538                 return;
1539
1540         device_path = get_device_path(dev);
1541
1542         fstype = discover_device_get_param(dev, "ID_FS_TYPE");
1543
1544         pb_log("remounting device %s read-only\n", device_path);
1545
1546         if (umount(dev->mount_path)) {
1547                 pb_log("Failed to unmount %s\n", dev->mount_path);
1548                 return;
1549         }
1550         dev->mounted_rw = dev->mounted = false;
1551
1552         if (dev->ramdisk) {
1553                 devmapper_merge_snapshot(dev);
1554                 /* device_path becomes stale after merge */
1555                 device_path = get_device_path(dev);
1556         }
1557
1558         if (try_mount(device_path, dev->mount_path, fstype,
1559                        MS_RDONLY | MS_SILENT, dev->ramdisk))
1560                 pb_log("Failed to remount %s read-only: %s\n",
1561                        device_path, strerror(errno));
1562         else
1563                 dev->mounted = true;
1564 }
1565
1566 void device_sync_snapshots(struct device_handler *handler, const char *device)
1567 {
1568         struct discover_device *dev = NULL;
1569         unsigned int i;
1570
1571         if (device) {
1572                 /* Find matching device and sync */
1573                 dev = device_lookup_by_name(handler, device);
1574                 if (!dev) {
1575                         pb_log("%s: device name '%s' unrecognised\n",
1576                                 __func__, device);
1577                         return;
1578                 }
1579                 if (dev->ramdisk)
1580                         device_release_write(dev, true);
1581                 else
1582                         pb_log("%s has no snapshot to merge, skipping\n",
1583                                 dev->device->id);
1584                 return;
1585         }
1586
1587         /* Otherwise sync all relevant devices */
1588         for (i = 0; i < handler->n_devices; i++) {
1589                 dev = handler->devices[i];
1590                 if (dev->device->type != DEVICE_TYPE_DISK &&
1591                         dev->device->type != DEVICE_TYPE_USB)
1592                         continue;
1593                 if (dev->ramdisk)
1594                         device_release_write(dev, true);
1595                 else
1596                         pb_log("%s has no snapshot to merge, skipping\n",
1597                                 dev->device->id);
1598         }
1599 }
1600
1601 #else
1602
1603 void device_handler_discover_context_commit(
1604                 struct device_handler *handler __attribute__((unused)),
1605                 struct discover_context *ctx __attribute__((unused)))
1606 {
1607         pb_log("%s stubbed out for test cases\n", __func__);
1608 }
1609
1610 static void device_handler_update_lang(const char *lang __attribute__((unused)))
1611 {
1612 }
1613
1614 static int device_handler_init_sources(
1615                 struct device_handler *handler __attribute__((unused)))
1616 {
1617         return 0;
1618 }
1619
1620 static void device_handler_reinit_sources(
1621                 struct device_handler *handler __attribute__((unused)))
1622 {
1623 }
1624
1625 static int umount_device(struct discover_device *dev __attribute__((unused)))
1626 {
1627         return 0;
1628 }
1629
1630 static int __attribute__((unused)) mount_device(
1631                 struct discover_device *dev __attribute__((unused)))
1632 {
1633         return 0;
1634 }
1635
1636 int device_request_write(struct discover_device *dev __attribute__((unused)),
1637                 bool *release)
1638 {
1639         *release = true;
1640         return 0;
1641 }
1642
1643 void device_release_write(struct discover_device *dev __attribute__((unused)),
1644         bool release __attribute__((unused)))
1645 {
1646 }
1647
1648 void device_sync_snapshots(
1649                 struct device_handler *handler __attribute__((unused)),
1650                 const char *device __attribute__((unused)))
1651 {
1652 }
1653
1654 #endif