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