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reload: implement reload/reexec logic
[elogind.git] / mount.c
1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
2
3 /***
4   This file is part of systemd.
5
6   Copyright 2010 Lennart Poettering
7
8   systemd is free software; you can redistribute it and/or modify it
9   under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2 of the License, or
11   (at your option) any later version.
12
13   systemd is distributed in the hope that it will be useful, but
14   WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16   General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
20 ***/
21
22 #include <errno.h>
23 #include <stdio.h>
24 #include <mntent.h>
25 #include <sys/epoll.h>
26 #include <signal.h>
27
28 #include "unit.h"
29 #include "mount.h"
30 #include "load-fragment.h"
31 #include "load-dropin.h"
32 #include "log.h"
33 #include "strv.h"
34 #include "mount-setup.h"
35 #include "unit-name.h"
36 #include "mount.h"
37 #include "dbus-mount.h"
38
39 static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = {
40         [MOUNT_DEAD] = UNIT_INACTIVE,
41         [MOUNT_MOUNTING] = UNIT_ACTIVATING,
42         [MOUNT_MOUNTING_DONE] = UNIT_ACTIVE,
43         [MOUNT_MOUNTED] = UNIT_ACTIVE,
44         [MOUNT_REMOUNTING] = UNIT_ACTIVE_RELOADING,
45         [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING,
46         [MOUNT_MOUNTING_SIGTERM] = UNIT_DEACTIVATING,
47         [MOUNT_MOUNTING_SIGKILL] = UNIT_DEACTIVATING,
48         [MOUNT_REMOUNTING_SIGTERM] = UNIT_ACTIVE_RELOADING,
49         [MOUNT_REMOUNTING_SIGKILL] = UNIT_ACTIVE_RELOADING,
50         [MOUNT_UNMOUNTING_SIGTERM] = UNIT_DEACTIVATING,
51         [MOUNT_UNMOUNTING_SIGKILL] = UNIT_DEACTIVATING,
52         [MOUNT_MAINTAINANCE] = UNIT_INACTIVE,
53 };
54
55 static void mount_init(Unit *u) {
56         Mount *m = MOUNT(u);
57
58         assert(u);
59         assert(u->meta.load_state == UNIT_STUB);
60
61         m->timeout_usec = DEFAULT_TIMEOUT_USEC;
62         exec_context_init(&m->exec_context);
63
64         /* We need to make sure that /bin/mount is always called in
65          * the same process group as us, so that the autofs kernel
66          * side doesn't send us another mount request while we are
67          * already trying to comply its last one. */
68         m->exec_context.no_setsid = true;
69
70         m->timer_watch.type = WATCH_INVALID;
71
72         m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
73 }
74
75 static void mount_unwatch_control_pid(Mount *m) {
76         assert(m);
77
78         if (m->control_pid <= 0)
79                 return;
80
81         unit_unwatch_pid(UNIT(m), m->control_pid);
82         m->control_pid = 0;
83 }
84
85 static void mount_parameters_done(MountParameters *p) {
86         assert(p);
87
88         free(p->what);
89         free(p->options);
90         free(p->fstype);
91
92         p->what = p->options = p->fstype = NULL;
93 }
94
95 static void mount_done(Unit *u) {
96         Mount *m = MOUNT(u);
97
98         assert(m);
99
100         free(m->where);
101         m->where = NULL;
102
103         mount_parameters_done(&m->parameters_etc_fstab);
104         mount_parameters_done(&m->parameters_proc_self_mountinfo);
105         mount_parameters_done(&m->parameters_fragment);
106
107         exec_context_done(&m->exec_context);
108         exec_command_done_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX);
109         m->control_command = NULL;
110
111         mount_unwatch_control_pid(m);
112
113         unit_unwatch_timer(u, &m->timer_watch);
114 }
115
116 static int mount_add_node_links(Mount *m) {
117         Unit *device;
118         char *e;
119         int r;
120         const char *what;
121
122         assert(m);
123
124         /* Adds in links to the device that this node is based on */
125
126         if (m->parameters_fragment.what)
127                 what = m->parameters_fragment.what;
128         else if (m->parameters_etc_fstab.what)
129                 what = m->parameters_etc_fstab.what;
130         else
131                 /* We observe kernel mounts only while they are live,
132                  * hence don't create any links for them */
133                 return 0;
134
135         if (!path_startswith(what, "/dev/"))
136                 return 0;
137
138         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
139                 return -ENOMEM;
140
141         r = manager_load_unit(UNIT(m)->meta.manager, e, NULL, &device);
142         free(e);
143
144         if (r < 0)
145                 return r;
146
147         if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, device)) < 0)
148                 return r;
149
150         if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, device)) < 0)
151                 return r;
152
153         if (UNIT(m)->meta.manager->running_as == MANAGER_INIT ||
154             UNIT(m)->meta.manager->running_as == MANAGER_SYSTEM)
155                 if ((r = unit_add_dependency(device, UNIT_WANTS, UNIT(m))) < 0)
156                         return r;
157
158         return 0;
159 }
160
161 static int mount_add_path_links(Mount *m) {
162         Meta *other;
163         int r;
164
165         assert(m);
166
167         /* Adds in link to other mount points, that might lie below or
168          * above us in the hierarchy */
169
170         LIST_FOREACH(units_per_type, other, UNIT(m)->meta.manager->units_per_type[UNIT_MOUNT]) {
171                 Mount *n;
172
173                 n = (Mount*) other;
174
175                 if (n == m)
176                         continue;
177
178                 if (m->meta.load_state != UNIT_LOADED)
179                         continue;
180
181                 if (path_startswith(m->where, n->where)) {
182
183                         if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, UNIT(other))) < 0)
184                                 return r;
185
186                         if (n->from_etc_fstab || n->from_fragment)
187                                 if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, UNIT(other))) < 0)
188                                         return r;
189
190                 } else if (path_startswith(n->where, m->where)) {
191
192                         if ((r = unit_add_dependency(UNIT(m), UNIT_BEFORE, UNIT(other))) < 0)
193                                 return r;
194
195                         if (m->from_etc_fstab || m->from_fragment)
196                                 if ((r = unit_add_dependency(UNIT(other), UNIT_REQUIRES, UNIT(m))) < 0)
197                                         return r;
198                 }
199         }
200
201         return 0;
202 }
203
204 static bool mount_test_option(const char *haystack, const char *needle) {
205         struct mntent me;
206
207         assert(needle);
208
209         /* Like glibc's hasmntopt(), but works on a string, not a
210          * struct mntent */
211
212         if (!haystack)
213                 return false;
214
215         zero(me);
216         me.mnt_opts = (char*) haystack;
217
218         return !!hasmntopt(&me, needle);
219 }
220
221 static int mount_add_target_links(Mount *m) {
222         const char *target;
223         MountParameters *p;
224         Unit *tu;
225         int r;
226         bool noauto, handle, automount;
227
228         assert(m);
229
230         if (m->from_fragment)
231                 p = &m->parameters_fragment;
232         else if (m->from_etc_fstab)
233                 p = &m->parameters_etc_fstab;
234         else
235                 return 0;
236
237         noauto = mount_test_option(p->options, MNTOPT_NOAUTO);
238         handle = mount_test_option(p->options, "comment=systemd.mount");
239         automount = mount_test_option(p->options, "comment=systemd.automount");
240
241         if (noauto && !handle && !automount)
242                 return 0;
243
244         if (mount_test_option(p->options, "_netdev") ||
245             fstype_is_network(p->fstype))
246                 target = SPECIAL_REMOTE_FS_TARGET;
247         else
248                 target = SPECIAL_LOCAL_FS_TARGET;
249
250         if ((r = manager_load_unit(UNIT(m)->meta.manager, target, NULL, &tu)) < 0)
251                 return r;
252
253         if (automount) {
254                 Unit *am;
255
256                 if ((r = unit_load_related_unit(UNIT(m), ".automount", &am)) < 0)
257                         return r;
258
259                 if ((r = unit_add_dependency(tu, UNIT_WANTS, UNIT(am))) < 0)
260                         return r;
261
262                 return unit_add_dependency(UNIT(am), UNIT_BEFORE, tu);
263
264         } else {
265
266                 if (handle)
267                         if ((r = unit_add_dependency(tu, UNIT_WANTS, UNIT(m))) < 0)
268                                 return r;
269
270                 return unit_add_dependency(UNIT(m), UNIT_BEFORE, tu);
271         }
272 }
273
274 static int mount_verify(Mount *m) {
275         bool b;
276         char *e;
277         assert(m);
278
279         if (UNIT(m)->meta.load_state != UNIT_LOADED)
280                 return 0;
281
282         if (!(e = unit_name_from_path(m->where, ".mount")))
283                 return -ENOMEM;
284
285         b = unit_has_name(UNIT(m), e);
286         free(e);
287
288         if (!b) {
289                 log_error("%s's Where setting doesn't match unit name. Refusing.", UNIT(m)->meta.id);
290                 return -EINVAL;
291         }
292
293         return 0;
294 }
295
296 static int mount_load(Unit *u) {
297         Mount *m = MOUNT(u);
298         int r;
299
300         assert(u);
301         assert(u->meta.load_state == UNIT_STUB);
302
303         if ((r = unit_load_fragment_and_dropin_optional(u)) < 0)
304                 return r;
305
306         /* This is a new unit? Then let's add in some extras */
307         if (u->meta.load_state == UNIT_LOADED) {
308
309                 if (!m->where)
310                         if (!(m->where = unit_name_to_path(u->meta.id)))
311                                 return -ENOMEM;
312
313                 path_kill_slashes(m->where);
314
315                 /* Minor validity checking */
316                 if ((m->parameters_fragment.options || m->parameters_fragment.fstype) && !m->parameters_fragment.what)
317                         return -EBADMSG;
318
319                 if (m->parameters_fragment.what)
320                         m->from_fragment = true;
321
322                 if ((r = mount_add_node_links(MOUNT(u))) < 0)
323                         return r;
324
325                 if ((r = mount_add_path_links(MOUNT(u))) < 0)
326                         return r;
327
328                 if ((r = mount_add_target_links(MOUNT(u))) < 0)
329                         return r;
330
331                 if ((r = unit_add_default_cgroup(u)) < 0)
332                         return r;
333         }
334
335         return mount_verify(m);
336 }
337
338 static int mount_notify_automount(Mount *m, int status) {
339         Unit *p;
340         int r;
341
342         assert(m);
343
344         if ((r = unit_get_related_unit(UNIT(m), ".automount", &p)) < 0)
345                 return r == -ENOENT ? 0 : r;
346
347         return automount_send_ready(AUTOMOUNT(p), status);
348 }
349
350 static void mount_set_state(Mount *m, MountState state) {
351         MountState old_state;
352         assert(m);
353
354         old_state = m->state;
355         m->state = state;
356
357         if (state != MOUNT_MOUNTING &&
358             state != MOUNT_MOUNTING_DONE &&
359             state != MOUNT_REMOUNTING &&
360             state != MOUNT_UNMOUNTING &&
361             state != MOUNT_MOUNTING_SIGTERM &&
362             state != MOUNT_MOUNTING_SIGKILL &&
363             state != MOUNT_UNMOUNTING_SIGTERM &&
364             state != MOUNT_UNMOUNTING_SIGKILL &&
365             state != MOUNT_REMOUNTING_SIGTERM &&
366             state != MOUNT_REMOUNTING_SIGKILL) {
367                 unit_unwatch_timer(UNIT(m), &m->timer_watch);
368                 mount_unwatch_control_pid(m);
369                 m->control_command = NULL;
370                 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
371         }
372
373         if (state == MOUNT_MOUNTED ||
374             state == MOUNT_REMOUNTING)
375                 mount_notify_automount(m, 0);
376         else if (state == MOUNT_DEAD ||
377                  state == MOUNT_UNMOUNTING ||
378                  state == MOUNT_MOUNTING_SIGTERM ||
379                  state == MOUNT_MOUNTING_SIGKILL ||
380                  state == MOUNT_REMOUNTING_SIGTERM ||
381                  state == MOUNT_REMOUNTING_SIGKILL ||
382                  state == MOUNT_UNMOUNTING_SIGTERM ||
383                  state == MOUNT_UNMOUNTING_SIGKILL ||
384                  state == MOUNT_MAINTAINANCE)
385                 mount_notify_automount(m, -ENODEV);
386
387         if (state != old_state)
388                 log_debug("%s changed %s â†’ %s",
389                           UNIT(m)->meta.id,
390                           mount_state_to_string(old_state),
391                           mount_state_to_string(state));
392
393         unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state]);
394 }
395
396 static int mount_coldplug(Unit *u) {
397         Mount *m = MOUNT(u);
398         MountState new_state = MOUNT_DEAD;
399         int r;
400
401         assert(m);
402         assert(m->state == MOUNT_DEAD);
403
404         if (m->deserialized_state != m->state)
405                 new_state = m->deserialized_state;
406         else if (m->from_proc_self_mountinfo)
407                 new_state = MOUNT_MOUNTED;
408
409         if (new_state != m->state) {
410
411                 if (new_state == MOUNT_MOUNTING ||
412                     new_state == MOUNT_MOUNTING_DONE ||
413                     new_state == MOUNT_REMOUNTING ||
414                     new_state == MOUNT_UNMOUNTING ||
415                     new_state == MOUNT_MOUNTING_SIGTERM ||
416                     new_state == MOUNT_MOUNTING_SIGKILL ||
417                     new_state == MOUNT_UNMOUNTING_SIGTERM ||
418                     new_state == MOUNT_UNMOUNTING_SIGKILL ||
419                     new_state == MOUNT_REMOUNTING_SIGTERM ||
420                     new_state == MOUNT_REMOUNTING_SIGKILL) {
421
422                         if (m->control_pid <= 0)
423                                 return -EBADMSG;
424
425                         if ((r = unit_watch_pid(UNIT(m), m->control_pid)) < 0)
426                                 return r;
427
428                         if ((r = unit_watch_timer(UNIT(m), m->timeout_usec, &m->timer_watch)) < 0)
429                                 return r;
430                 }
431
432                 mount_set_state(m, new_state);
433         }
434
435         return 0;
436 }
437
438 static void mount_dump(Unit *u, FILE *f, const char *prefix) {
439         Mount *m = MOUNT(u);
440         MountParameters *p;
441
442         assert(m);
443         assert(f);
444
445         if (m->from_proc_self_mountinfo)
446                 p = &m->parameters_proc_self_mountinfo;
447         else if (m->from_fragment)
448                 p = &m->parameters_fragment;
449         else
450                 p = &m->parameters_etc_fstab;
451
452         fprintf(f,
453                 "%sMount State: %s\n"
454                 "%sWhere: %s\n"
455                 "%sWhat: %s\n"
456                 "%sFile System Type: %s\n"
457                 "%sOptions: %s\n"
458                 "%sFrom /etc/fstab: %s\n"
459                 "%sFrom /proc/self/mountinfo: %s\n"
460                 "%sFrom fragment: %s\n"
461                 "%sKillMode: %s\n",
462                 prefix, mount_state_to_string(m->state),
463                 prefix, m->where,
464                 prefix, strna(p->what),
465                 prefix, strna(p->fstype),
466                 prefix, strna(p->options),
467                 prefix, yes_no(m->from_etc_fstab),
468                 prefix, yes_no(m->from_proc_self_mountinfo),
469                 prefix, yes_no(m->from_fragment),
470                 prefix, kill_mode_to_string(m->kill_mode));
471
472         if (m->control_pid > 0)
473                 fprintf(f,
474                         "%sControl PID: %llu\n",
475                         prefix, (unsigned long long) m->control_pid);
476
477         exec_context_dump(&m->exec_context, f, prefix);
478 }
479
480 static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
481         pid_t pid;
482         int r;
483
484         assert(m);
485         assert(c);
486         assert(_pid);
487
488         if ((r = unit_watch_timer(UNIT(m), m->timeout_usec, &m->timer_watch)) < 0)
489                 goto fail;
490
491         if ((r = exec_spawn(c,
492                             NULL,
493                             &m->exec_context,
494                             NULL, 0,
495                             true,
496                             true,
497                             UNIT(m)->meta.manager->confirm_spawn,
498                             UNIT(m)->meta.cgroup_bondings,
499                             &pid)) < 0)
500                 goto fail;
501
502         if ((r = unit_watch_pid(UNIT(m), pid)) < 0)
503                 /* FIXME: we need to do something here */
504                 goto fail;
505
506         *_pid = pid;
507
508         return 0;
509
510 fail:
511         unit_unwatch_timer(UNIT(m), &m->timer_watch);
512
513         return r;
514 }
515
516 static void mount_enter_dead(Mount *m, bool success) {
517         assert(m);
518
519         if (!success)
520                 m->failure = true;
521
522         mount_set_state(m, m->failure ? MOUNT_MAINTAINANCE : MOUNT_DEAD);
523 }
524
525 static void mount_enter_mounted(Mount *m, bool success) {
526         assert(m);
527
528         if (!success)
529                 m->failure = true;
530
531         mount_set_state(m, MOUNT_MOUNTED);
532 }
533
534 static void mount_enter_signal(Mount *m, MountState state, bool success) {
535         int r;
536         bool sent = false;
537
538         assert(m);
539
540         if (!success)
541                 m->failure = true;
542
543         if (m->kill_mode != KILL_NONE) {
544                 int sig = (state == MOUNT_MOUNTING_SIGTERM ||
545                            state == MOUNT_UNMOUNTING_SIGTERM ||
546                            state == MOUNT_REMOUNTING_SIGTERM) ? SIGTERM : SIGKILL;
547
548                 if (m->kill_mode == KILL_CONTROL_GROUP) {
549
550                         if ((r = cgroup_bonding_kill_list(UNIT(m)->meta.cgroup_bondings, sig)) < 0) {
551                                 if (r != -EAGAIN && r != -ESRCH)
552                                         goto fail;
553                         } else
554                                 sent = true;
555                 }
556
557                 if (!sent && m->control_pid > 0)
558                         if (kill(m->kill_mode == KILL_PROCESS ? m->control_pid : -m->control_pid, sig) < 0 && errno != ESRCH) {
559                                 r = -errno;
560                                 goto fail;
561                         }
562         }
563
564         if (sent) {
565                 if ((r = unit_watch_timer(UNIT(m), m->timeout_usec, &m->timer_watch)) < 0)
566                         goto fail;
567
568                 mount_set_state(m, state);
569         } else if (state == MOUNT_REMOUNTING_SIGTERM || state == MOUNT_REMOUNTING_SIGKILL)
570                 mount_enter_mounted(m, true);
571         else
572                 mount_enter_dead(m, true);
573
574         return;
575
576 fail:
577         log_warning("%s failed to kill processes: %s", UNIT(m)->meta.id, strerror(-r));
578
579         if (state == MOUNT_REMOUNTING_SIGTERM || state == MOUNT_REMOUNTING_SIGKILL)
580                 mount_enter_mounted(m, false);
581         else
582                 mount_enter_dead(m, false);
583 }
584
585 static void mount_enter_unmounting(Mount *m, bool success) {
586         int r;
587
588         assert(m);
589
590         if (!success)
591                 m->failure = true;
592
593         m->control_command_id = MOUNT_EXEC_UNMOUNT;
594         m->control_command = m->exec_command + MOUNT_EXEC_UNMOUNT;
595
596         if ((r = exec_command_set(
597                              m->control_command,
598                              "/bin/umount",
599                              m->where,
600                              NULL)) < 0)
601                 goto fail;
602
603         mount_unwatch_control_pid(m);
604
605         if ((r = mount_spawn(m, m->control_command, &m->control_pid)) < 0)
606                 goto fail;
607
608         mount_set_state(m, MOUNT_UNMOUNTING);
609
610         return;
611
612 fail:
613         log_warning("%s failed to run umount exectuable: %s", UNIT(m)->meta.id, strerror(-r));
614         mount_enter_mounted(m, false);
615 }
616
617 static void mount_enter_mounting(Mount *m) {
618         int r;
619
620         assert(m);
621
622         m->control_command_id = MOUNT_EXEC_MOUNT;
623         m->control_command = m->exec_command + MOUNT_EXEC_MOUNT;
624
625         if (m->from_fragment)
626                 r = exec_command_set(
627                                 m->control_command,
628                                 "/bin/mount",
629                                 m->parameters_fragment.what,
630                                 m->where,
631                                 "-t", m->parameters_fragment.fstype,
632                                 m->parameters_fragment.options ? "-o" : NULL, m->parameters_fragment.options,
633                                 NULL);
634         else if (m->from_etc_fstab)
635                 r = exec_command_set(
636                                 m->control_command,
637                                 "/bin/mount",
638                                 m->where,
639                                 NULL);
640         else
641                 r = -ENOENT;
642
643         if (r < 0)
644                 goto fail;
645
646         mount_unwatch_control_pid(m);
647
648         if ((r = mount_spawn(m, m->control_command, &m->control_pid)) < 0)
649                 goto fail;
650
651         mount_set_state(m, MOUNT_MOUNTING);
652
653         return;
654
655 fail:
656         log_warning("%s failed to run mount exectuable: %s", UNIT(m)->meta.id, strerror(-r));
657         mount_enter_dead(m, false);
658 }
659
660 static void mount_enter_mounting_done(Mount *m) {
661         assert(m);
662
663         mount_set_state(m, MOUNT_MOUNTING_DONE);
664 }
665
666 static void mount_enter_remounting(Mount *m, bool success) {
667         int r;
668
669         assert(m);
670
671         if (!success)
672                 m->failure = true;
673
674         m->control_command_id = MOUNT_EXEC_REMOUNT;
675         m->control_command = m->exec_command + MOUNT_EXEC_REMOUNT;
676
677         if (m->from_fragment) {
678                 char *buf = NULL;
679                 const char *o;
680
681                 if (m->parameters_fragment.options) {
682                         if (!(buf = strappend("remount,", m->parameters_fragment.options))) {
683                                 r = -ENOMEM;
684                                 goto fail;
685                         }
686
687                         o = buf;
688                 } else
689                         o = "remount";
690
691                 r = exec_command_set(
692                                 m->control_command,
693                                 "/bin/mount",
694                                 m->parameters_fragment.what,
695                                 m->where,
696                                 "-t", m->parameters_fragment.fstype,
697                                 "-o", o,
698                                 NULL);
699
700                 free(buf);
701         } else if (m->from_etc_fstab)
702                 r = exec_command_set(
703                                 m->control_command,
704                                 "/bin/mount",
705                                 m->where,
706                                 "-o", "remount",
707                                 NULL);
708         else
709                 r = -ENOENT;
710
711         if (r < 0) {
712                 r = -ENOMEM;
713                 goto fail;
714         }
715
716         mount_unwatch_control_pid(m);
717
718         if ((r = mount_spawn(m, m->control_command, &m->control_pid)) < 0)
719                 goto fail;
720
721         mount_set_state(m, MOUNT_REMOUNTING);
722
723         return;
724
725 fail:
726         mount_enter_mounted(m, false);
727 }
728
729 static int mount_start(Unit *u) {
730         Mount *m = MOUNT(u);
731
732         assert(m);
733
734         /* We cannot fulfill this request right now, try again later
735          * please! */
736         if (m->state == MOUNT_UNMOUNTING ||
737             m->state == MOUNT_UNMOUNTING_SIGTERM ||
738             m->state == MOUNT_UNMOUNTING_SIGKILL)
739                 return -EAGAIN;
740
741         /* Already on it! */
742         if (m->state == MOUNT_MOUNTING ||
743             m->state == MOUNT_MOUNTING_SIGTERM ||
744             m->state == MOUNT_MOUNTING_SIGKILL)
745                 return 0;
746
747         assert(m->state == MOUNT_DEAD || m->state == MOUNT_MAINTAINANCE);
748
749         m->failure = false;
750         mount_enter_mounting(m);
751         return 0;
752 }
753
754 static int mount_stop(Unit *u) {
755         Mount *m = MOUNT(u);
756
757         assert(m);
758
759         /* Cann't do this right now. */
760         if (m->state == MOUNT_MOUNTING ||
761             m->state == MOUNT_MOUNTING_DONE ||
762             m->state == MOUNT_MOUNTING_SIGTERM ||
763             m->state == MOUNT_MOUNTING_SIGKILL ||
764             m->state == MOUNT_REMOUNTING ||
765             m->state == MOUNT_REMOUNTING_SIGTERM ||
766             m->state == MOUNT_REMOUNTING_SIGKILL)
767                 return -EAGAIN;
768
769         /* Already on it */
770         if (m->state == MOUNT_UNMOUNTING ||
771             m->state == MOUNT_UNMOUNTING_SIGKILL ||
772             m->state == MOUNT_UNMOUNTING_SIGTERM)
773                 return 0;
774
775         assert(m->state == MOUNT_MOUNTED);
776
777         mount_enter_unmounting(m, true);
778         return 0;
779 }
780
781 static int mount_reload(Unit *u) {
782         Mount *m = MOUNT(u);
783
784         assert(m);
785
786         if (m->state == MOUNT_MOUNTING_DONE)
787                 return -EAGAIN;
788
789         assert(m->state == MOUNT_MOUNTED);
790
791         mount_enter_remounting(m, true);
792         return 0;
793 }
794
795 static int mount_serialize(Unit *u, FILE *f, FDSet *fds) {
796         Mount *m = MOUNT(u);
797
798         assert(m);
799         assert(f);
800         assert(fds);
801
802         unit_serialize_item(u, f, "state", mount_state_to_string(m->state));
803         unit_serialize_item(u, f, "failure", yes_no(m->failure));
804
805         if (m->control_pid > 0)
806                 unit_serialize_item_format(u, f, "control-pid", "%u", (unsigned) m->control_pid);
807
808         if (m->control_command_id >= 0)
809                 unit_serialize_item(u, f, "control-command", mount_exec_command_to_string(m->control_command_id));
810
811         return 0;
812 }
813
814 static int mount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
815         Mount *m = MOUNT(u);
816         int r;
817
818         assert(u);
819         assert(key);
820         assert(value);
821         assert(fds);
822
823         if (streq(key, "state")) {
824                 MountState state;
825
826                 if ((state = mount_state_from_string(value)) < 0)
827                         log_debug("Failed to parse state value %s", value);
828                 else
829                         m->deserialized_state = state;
830         } else if (streq(key, "failure")) {
831                 int b;
832
833                 if ((b = parse_boolean(value)) < 0)
834                         log_debug("Failed to parse failure value %s", value);
835                 else
836                         m->failure = b || m->failure;
837
838         } else if (streq(key, "control-pid")) {
839                 unsigned pid;
840
841                 if ((r = safe_atou(value, &pid)) < 0 || pid <= 0)
842                         log_debug("Failed to parse control-pid value %s", value);
843                 else
844                         m->control_pid = (pid_t) pid;
845         } else if (streq(key, "control-command")) {
846                 MountExecCommand id;
847
848                 if ((id = mount_exec_command_from_string(value)) < 0)
849                         log_debug("Failed to parse exec-command value %s", value);
850                 else {
851                         m->control_command_id = id;
852                         m->control_command = m->exec_command + id;
853                 }
854
855         } else
856                 log_debug("Unknown serialization key '%s'", key);
857
858         return 0;
859 }
860
861 static UnitActiveState mount_active_state(Unit *u) {
862         assert(u);
863
864         return state_translation_table[MOUNT(u)->state];
865 }
866
867 static const char *mount_sub_state_to_string(Unit *u) {
868         assert(u);
869
870         return mount_state_to_string(MOUNT(u)->state);
871 }
872
873 static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
874         Mount *m = MOUNT(u);
875         bool success;
876
877         assert(m);
878         assert(pid >= 0);
879
880         success = code == CLD_EXITED && status == 0;
881         m->failure = m->failure || !success;
882
883         assert(m->control_pid == pid);
884         m->control_pid = 0;
885
886         if (m->control_command) {
887                 exec_status_fill(&m->control_command->exec_status, pid, code, status);
888                 m->control_command = NULL;
889                 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
890         }
891
892         log_debug("%s control process exited, code=%s status=%i", u->meta.id, sigchld_code_to_string(code), status);
893
894         /* Note that mount(8) returning and the kernel sending us a
895          * mount table change event might happen out-of-order. If an
896          * operation succeed we assume the kernel will follow soon too
897          * and already change into the resulting state.  If it fails
898          * we check if the kernel still knows about the mount. and
899          * change state accordingly. */
900
901         switch (m->state) {
902
903         case MOUNT_MOUNTING:
904         case MOUNT_MOUNTING_DONE:
905         case MOUNT_MOUNTING_SIGKILL:
906         case MOUNT_MOUNTING_SIGTERM:
907         case MOUNT_REMOUNTING:
908         case MOUNT_REMOUNTING_SIGKILL:
909         case MOUNT_REMOUNTING_SIGTERM:
910
911                 if (success && m->from_proc_self_mountinfo)
912                         mount_enter_mounted(m, true);
913                 else if (m->from_proc_self_mountinfo)
914                         mount_enter_mounted(m, false);
915                 else
916                         mount_enter_dead(m, false);
917                 break;
918
919         case MOUNT_UNMOUNTING:
920         case MOUNT_UNMOUNTING_SIGKILL:
921         case MOUNT_UNMOUNTING_SIGTERM:
922
923                 if (success)
924                         mount_enter_dead(m, true);
925                 else if (m->from_proc_self_mountinfo)
926                         mount_enter_mounted(m, false);
927                 else
928                         mount_enter_dead(m, false);
929                 break;
930
931         default:
932                 assert_not_reached("Uh, control process died at wrong time.");
933         }
934 }
935
936 static void mount_timer_event(Unit *u, uint64_t elapsed, Watch *w) {
937         Mount *m = MOUNT(u);
938
939         assert(m);
940         assert(elapsed == 1);
941         assert(w == &m->timer_watch);
942
943         switch (m->state) {
944
945         case MOUNT_MOUNTING:
946         case MOUNT_MOUNTING_DONE:
947                 log_warning("%s mounting timed out. Stopping.", u->meta.id);
948                 mount_enter_signal(m, MOUNT_MOUNTING_SIGTERM, false);
949                 break;
950
951         case MOUNT_REMOUNTING:
952                 log_warning("%s remounting timed out. Stopping.", u->meta.id);
953                 mount_enter_signal(m, MOUNT_REMOUNTING_SIGTERM, false);
954                 break;
955
956         case MOUNT_UNMOUNTING:
957                 log_warning("%s unmounting timed out. Stopping.", u->meta.id);
958                 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, false);
959                 break;
960
961         case MOUNT_MOUNTING_SIGTERM:
962                 log_warning("%s mounting timed out. Killing.", u->meta.id);
963                 mount_enter_signal(m, MOUNT_MOUNTING_SIGKILL, false);
964                 break;
965
966         case MOUNT_REMOUNTING_SIGTERM:
967                 log_warning("%s remounting timed out. Killing.", u->meta.id);
968                 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, false);
969                 break;
970
971         case MOUNT_UNMOUNTING_SIGTERM:
972                 log_warning("%s unmounting timed out. Killing.", u->meta.id);
973                 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, false);
974                 break;
975
976         case MOUNT_MOUNTING_SIGKILL:
977         case MOUNT_REMOUNTING_SIGKILL:
978         case MOUNT_UNMOUNTING_SIGKILL:
979                 log_warning("%s mount process still around after SIGKILL. Ignoring.", u->meta.id);
980
981                 if (m->from_proc_self_mountinfo)
982                         mount_enter_mounted(m, false);
983                 else
984                         mount_enter_dead(m, false);
985                 break;
986
987         default:
988                 assert_not_reached("Timeout at wrong time.");
989         }
990 }
991
992 static int mount_add_one(
993                 Manager *m,
994                 const char *what,
995                 const char *where,
996                 const char *options,
997                 const char *fstype,
998                 bool from_proc_self_mountinfo,
999                 bool set_flags) {
1000         int r;
1001         Unit *u;
1002         bool delete;
1003         char *e, *w = NULL, *o = NULL, *f = NULL;
1004         MountParameters *mp;
1005
1006         assert(m);
1007         assert(what);
1008         assert(where);
1009         assert(options);
1010         assert(fstype);
1011
1012         assert(!set_flags || from_proc_self_mountinfo);
1013
1014         /* Ignore API mount points. They should never be referenced in
1015          * dependencies ever. */
1016         if (mount_point_is_api(where))
1017                 return 0;
1018
1019         if (streq(fstype, "autofs"))
1020                 return 0;
1021
1022         /* probably some kind of swap, which we don't cover for now */
1023         if (where[0] != '/')
1024                 return 0;
1025
1026         if (!(e = unit_name_from_path(where, ".mount")))
1027                 return -ENOMEM;
1028
1029         if (!(u = manager_get_unit(m, e))) {
1030                 delete = true;
1031
1032                 if (!(u = unit_new(m))) {
1033                         free(e);
1034                         return -ENOMEM;
1035                 }
1036
1037                 r = unit_add_name(u, e);
1038                 free(e);
1039
1040                 if (r < 0)
1041                         goto fail;
1042
1043                 if (!(MOUNT(u)->where = strdup(where))) {
1044                             r = -ENOMEM;
1045                             goto fail;
1046                     }
1047
1048                 if ((r = unit_set_description(u, where)) < 0)
1049                         goto fail;
1050
1051                 unit_add_to_load_queue(u);
1052         } else {
1053                 delete = false;
1054                 free(e);
1055         }
1056
1057         if (!(w = strdup(what)) ||
1058             !(o = strdup(options)) ||
1059             !(f = strdup(fstype))) {
1060                 r = -ENOMEM;
1061                 goto fail;
1062         }
1063
1064         if (from_proc_self_mountinfo) {
1065                 mp = &MOUNT(u)->parameters_proc_self_mountinfo;
1066
1067                 if (set_flags) {
1068                         MOUNT(u)->is_mounted = true;
1069                         MOUNT(u)->just_mounted = !MOUNT(u)->from_proc_self_mountinfo;
1070                         MOUNT(u)->just_changed = !streq_ptr(MOUNT(u)->parameters_proc_self_mountinfo.options, o);
1071                 }
1072
1073                 MOUNT(u)->from_proc_self_mountinfo = true;
1074
1075         } else {
1076                 mp = &MOUNT(u)->parameters_etc_fstab;
1077
1078                 MOUNT(u)->from_etc_fstab = true;
1079         }
1080
1081         free(mp->what);
1082         mp->what = w;
1083
1084         free(mp->options);
1085         mp->options = o;
1086
1087         free(mp->fstype);
1088         mp->fstype = f;
1089
1090         unit_add_to_dbus_queue(u);
1091
1092         return 0;
1093
1094 fail:
1095         free(w);
1096         free(o);
1097         free(f);
1098
1099         if (delete && u)
1100                 unit_free(u);
1101
1102         return 0;
1103 }
1104
1105 static char *fstab_node_to_udev_node(char *p) {
1106         char *dn, *t;
1107         int r;
1108
1109         /* FIXME: to follow udev's logic 100% we need to leave valid
1110          * UTF8 chars unescaped */
1111
1112         if (startswith(p, "LABEL=")) {
1113
1114                 if (!(t = xescape(p+6, "/ ")))
1115                         return NULL;
1116
1117                 r = asprintf(&dn, "/dev/disk/by-label/%s", t);
1118                 free(t);
1119
1120                 if (r < 0)
1121                         return NULL;
1122
1123                 return dn;
1124         }
1125
1126         if (startswith(p, "UUID=")) {
1127
1128                 if (!(t = xescape(p+5, "/ ")))
1129                         return NULL;
1130
1131                 r = asprintf(&dn, "/dev/disk/by-uuid/%s", ascii_strlower(t));
1132                 free(t);
1133
1134                 if (r < 0)
1135                         return NULL;
1136
1137                 return dn;
1138         }
1139
1140         return strdup(p);
1141 }
1142
1143 static int mount_load_etc_fstab(Manager *m) {
1144         FILE *f;
1145         int r;
1146         struct mntent* me;
1147
1148         assert(m);
1149
1150         errno = 0;
1151         if (!(f = setmntent("/etc/fstab", "r")))
1152                 return -errno;
1153
1154         while ((me = getmntent(f))) {
1155                 char *where, *what;
1156
1157                 if (!(what = fstab_node_to_udev_node(me->mnt_fsname))) {
1158                         r = -ENOMEM;
1159                         goto finish;
1160                 }
1161
1162                 if (!(where = strdup(me->mnt_dir))) {
1163                         free(what);
1164                         r = -ENOMEM;
1165                         goto finish;
1166                 }
1167
1168                 if (what[0] == '/')
1169                         path_kill_slashes(what);
1170
1171                 if (where[0] == '/')
1172                         path_kill_slashes(where);
1173
1174                 r = mount_add_one(m, what, where, me->mnt_opts, me->mnt_type, false, false);
1175                 free(what);
1176                 free(where);
1177
1178                 if (r < 0)
1179                         goto finish;
1180         }
1181
1182         r = 0;
1183 finish:
1184
1185         endmntent(f);
1186         return r;
1187 }
1188
1189 static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) {
1190         int r;
1191         char *device, *path, *options, *fstype, *d, *p;
1192
1193         assert(m);
1194
1195         rewind(m->proc_self_mountinfo);
1196
1197         for (;;) {
1198                 int k;
1199
1200                 device = path = options = fstype = d = p = NULL;
1201
1202                 if ((k = fscanf(m->proc_self_mountinfo,
1203                                 "%*s "       /* (1) mount id */
1204                                 "%*s "       /* (2) parent id */
1205                                 "%*s "       /* (3) major:minor */
1206                                 "%*s "       /* (4) root */
1207                                 "%ms "       /* (5) mount point */
1208                                 "%ms"        /* (6) mount options */
1209                                 "%*[^-]"     /* (7) optional fields */
1210                                 "- "         /* (8) seperator */
1211                                 "%ms "       /* (9) file system type */
1212                                 "%ms"        /* (10) mount source */
1213                                 "%*[^\n]",   /* some rubbish at the end */
1214                                 &path,
1215                                 &options,
1216                                 &fstype,
1217                                 &device)) != 4) {
1218
1219                         if (k == EOF)
1220                                 break;
1221
1222                         r = -EBADMSG;
1223                         goto finish;
1224                 }
1225
1226                 if (!(d = cunescape(device)) ||
1227                     !(p = cunescape(path))) {
1228                         r = -ENOMEM;
1229                         goto finish;
1230                 }
1231
1232                 if ((r = mount_add_one(m, d, p, options, fstype, true, set_flags)) < 0)
1233                         goto finish;
1234
1235                 free(device);
1236                 free(path);
1237                 free(options);
1238                 free(fstype);
1239                 free(d);
1240                 free(p);
1241         }
1242
1243         r = 0;
1244
1245 finish:
1246         free(device);
1247         free(path);
1248         free(options);
1249         free(fstype);
1250         free(d);
1251         free(p);
1252
1253         return r;
1254 }
1255
1256 static void mount_shutdown(Manager *m) {
1257         assert(m);
1258
1259         if (m->proc_self_mountinfo) {
1260                 fclose(m->proc_self_mountinfo);
1261                 m->proc_self_mountinfo = NULL;
1262         }
1263 }
1264
1265 static int mount_enumerate(Manager *m) {
1266         int r;
1267         struct epoll_event ev;
1268         assert(m);
1269
1270         if (!m->proc_self_mountinfo) {
1271                 if (!(m->proc_self_mountinfo = fopen("/proc/self/mountinfo", "re")))
1272                         return -errno;
1273
1274                 m->mount_watch.type = WATCH_MOUNT;
1275                 m->mount_watch.fd = fileno(m->proc_self_mountinfo);
1276
1277                 zero(ev);
1278                 ev.events = EPOLLERR;
1279                 ev.data.ptr = &m->mount_watch;
1280
1281                 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->mount_watch.fd, &ev) < 0)
1282                         return -errno;
1283         }
1284
1285         if ((r = mount_load_etc_fstab(m)) < 0)
1286                 goto fail;
1287
1288         if ((r = mount_load_proc_self_mountinfo(m, false)) < 0)
1289                 goto fail;
1290
1291         return 0;
1292
1293 fail:
1294         mount_shutdown(m);
1295         return r;
1296 }
1297
1298 void mount_fd_event(Manager *m, int events) {
1299         Meta *meta;
1300         int r;
1301
1302         assert(m);
1303         assert(events == EPOLLERR);
1304
1305         /* The manager calls this for every fd event happening on the
1306          * /proc/self/mountinfo file, which informs us about mounting
1307          * table changes */
1308
1309         if ((r = mount_load_proc_self_mountinfo(m, true)) < 0) {
1310                 log_error("Failed to reread /proc/self/mountinfo: %s", strerror(-errno));
1311
1312                 /* Reset flags, just in case, for later calls */
1313                 LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_MOUNT]) {
1314                         Mount *mount = (Mount*) meta;
1315
1316                         mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1317                 }
1318
1319                 return;
1320         }
1321
1322         manager_dispatch_load_queue(m);
1323
1324         LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_MOUNT]) {
1325                 Mount *mount = (Mount*) meta;
1326
1327                 if (!mount->is_mounted) {
1328                         /* This has just been unmounted. */
1329
1330                         mount->from_proc_self_mountinfo = false;
1331
1332                         switch (mount->state) {
1333
1334                         case MOUNT_MOUNTED:
1335                                 mount_enter_dead(mount, true);
1336                                 break;
1337
1338                         default:
1339                                 mount_set_state(mount, mount->state);
1340                                 break;
1341
1342                         }
1343
1344                 } else if (mount->just_mounted || mount->just_changed) {
1345
1346                         /* New or changed entrymount */
1347
1348                         switch (mount->state) {
1349
1350                         case MOUNT_DEAD:
1351                         case MOUNT_MAINTAINANCE:
1352                                 mount_enter_mounted(mount, true);
1353                                 break;
1354
1355                         case MOUNT_MOUNTING:
1356                                 mount_enter_mounting_done(mount);
1357                                 break;
1358
1359                         default:
1360                                 /* Nothing really changed, but let's
1361                                  * issue an notification call
1362                                  * nonetheless, in case somebody is
1363                                  * waiting for this. (e.g. file system
1364                                  * ro/rw remounts.) */
1365                                 mount_set_state(mount, mount->state);
1366                                 break;
1367                         }
1368                 }
1369
1370                 /* Reset the flags for later calls */
1371                 mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1372         }
1373 }
1374
1375 int mount_path_is_mounted(Manager *m, const char* path) {
1376         char *t;
1377         int r;
1378
1379         assert(m);
1380         assert(path);
1381
1382         if (path[0] != '/')
1383                 return 1;
1384
1385         if (!(t = strdup(path)))
1386                 return -ENOMEM;
1387
1388         path_kill_slashes(t);
1389
1390         for (;;) {
1391                 char *e, *slash;
1392                 Unit *u;
1393
1394                 if (!(e = unit_name_from_path(t, ".mount"))) {
1395                         r = -ENOMEM;
1396                         goto finish;
1397                 }
1398
1399                 u = manager_get_unit(m, e);
1400                 free(e);
1401
1402                 if (u &&
1403                     (MOUNT(u)->from_etc_fstab || MOUNT(u)->from_fragment) &&
1404                     MOUNT(u)->state != MOUNT_MOUNTED) {
1405                         r = 0;
1406                         goto finish;
1407                 }
1408
1409                 assert_se(slash = strrchr(t, '/'));
1410
1411                 if (slash == t) {
1412                         r = 1;
1413                         goto finish;
1414                 }
1415
1416                 *slash = 0;
1417         }
1418
1419         r = 1;
1420
1421 finish:
1422         free(t);
1423         return r;
1424 }
1425
1426 static const char* const mount_state_table[_MOUNT_STATE_MAX] = {
1427         [MOUNT_DEAD] = "dead",
1428         [MOUNT_MOUNTING] = "mounting",
1429         [MOUNT_MOUNTING_DONE] = "mounting-done",
1430         [MOUNT_MOUNTED] = "mounted",
1431         [MOUNT_REMOUNTING] = "remounting",
1432         [MOUNT_UNMOUNTING] = "unmounting",
1433         [MOUNT_MOUNTING_SIGTERM] = "mounting-sigterm",
1434         [MOUNT_MOUNTING_SIGKILL] = "mounting-sigkill",
1435         [MOUNT_REMOUNTING_SIGTERM] = "remounting-sigterm",
1436         [MOUNT_REMOUNTING_SIGKILL] = "remounting-sigkill",
1437         [MOUNT_UNMOUNTING_SIGTERM] = "unmounting-sigterm",
1438         [MOUNT_UNMOUNTING_SIGKILL] = "unmounting-sigkill",
1439         [MOUNT_MAINTAINANCE] = "maintainance"
1440 };
1441
1442 DEFINE_STRING_TABLE_LOOKUP(mount_state, MountState);
1443
1444 static const char* const mount_exec_command_table[_MOUNT_EXEC_COMMAND_MAX] = {
1445         [MOUNT_EXEC_MOUNT] = "ExecMount",
1446         [MOUNT_EXEC_UNMOUNT] = "ExecUnmount",
1447         [MOUNT_EXEC_REMOUNT] = "ExecRemount",
1448 };
1449
1450 DEFINE_STRING_TABLE_LOOKUP(mount_exec_command, MountExecCommand);
1451
1452 const UnitVTable mount_vtable = {
1453         .suffix = ".mount",
1454
1455         .no_alias = true,
1456         .no_instances = true,
1457
1458         .init = mount_init,
1459         .load = mount_load,
1460         .done = mount_done,
1461
1462         .coldplug = mount_coldplug,
1463
1464         .dump = mount_dump,
1465
1466         .start = mount_start,
1467         .stop = mount_stop,
1468         .reload = mount_reload,
1469
1470         .serialize = mount_serialize,
1471         .deserialize_item = mount_deserialize_item,
1472
1473         .active_state = mount_active_state,
1474         .sub_state_to_string = mount_sub_state_to_string,
1475
1476         .sigchld_event = mount_sigchld_event,
1477         .timer_event = mount_timer_event,
1478
1479         .bus_message_handler = bus_mount_message_handler,
1480
1481         .enumerate = mount_enumerate,
1482         .shutdown = mount_shutdown
1483 };