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Merge pull request #6948 from pfl/radv_emit_dns
[thirdparty/systemd.git] / src / core / mount.c
1 /***
2 This file is part of systemd.
3
4 Copyright 2010 Lennart Poettering
5
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
10
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
18 ***/
19
20 #include <errno.h>
21 #include <signal.h>
22 #include <stdio.h>
23 #include <sys/epoll.h>
24
25 #include "sd-messages.h"
26
27 #include "alloc-util.h"
28 #include "dbus-mount.h"
29 #include "escape.h"
30 #include "exit-status.h"
31 #include "format-util.h"
32 #include "fstab-util.h"
33 #include "log.h"
34 #include "manager.h"
35 #include "mkdir.h"
36 #include "mount-setup.h"
37 #include "mount-util.h"
38 #include "mount.h"
39 #include "parse-util.h"
40 #include "path-util.h"
41 #include "process-util.h"
42 #include "special.h"
43 #include "string-table.h"
44 #include "string-util.h"
45 #include "strv.h"
46 #include "unit-name.h"
47 #include "unit.h"
48
49 #define RETRY_UMOUNT_MAX 32
50
51 DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_table*, mnt_free_table);
52 DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_iter*, mnt_free_iter);
53
54 static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = {
55 [MOUNT_DEAD] = UNIT_INACTIVE,
56 [MOUNT_MOUNTING] = UNIT_ACTIVATING,
57 [MOUNT_MOUNTING_DONE] = UNIT_ACTIVE,
58 [MOUNT_MOUNTED] = UNIT_ACTIVE,
59 [MOUNT_REMOUNTING] = UNIT_RELOADING,
60 [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING,
61 [MOUNT_REMOUNTING_SIGTERM] = UNIT_RELOADING,
62 [MOUNT_REMOUNTING_SIGKILL] = UNIT_RELOADING,
63 [MOUNT_UNMOUNTING_SIGTERM] = UNIT_DEACTIVATING,
64 [MOUNT_UNMOUNTING_SIGKILL] = UNIT_DEACTIVATING,
65 [MOUNT_FAILED] = UNIT_FAILED
66 };
67
68 static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
69 static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata);
70
71 static bool MOUNT_STATE_WITH_PROCESS(MountState state) {
72 return IN_SET(state,
73 MOUNT_MOUNTING,
74 MOUNT_MOUNTING_DONE,
75 MOUNT_REMOUNTING,
76 MOUNT_REMOUNTING_SIGTERM,
77 MOUNT_REMOUNTING_SIGKILL,
78 MOUNT_UNMOUNTING,
79 MOUNT_UNMOUNTING_SIGTERM,
80 MOUNT_UNMOUNTING_SIGKILL);
81 }
82
83 static bool mount_needs_network(const char *options, const char *fstype) {
84 if (fstab_test_option(options, "_netdev\0"))
85 return true;
86
87 if (fstype && fstype_is_network(fstype))
88 return true;
89
90 return false;
91 }
92
93 static bool mount_is_network(const MountParameters *p) {
94 assert(p);
95
96 return mount_needs_network(p->options, p->fstype);
97 }
98
99 static bool mount_is_loop(const MountParameters *p) {
100 assert(p);
101
102 if (fstab_test_option(p->options, "loop\0"))
103 return true;
104
105 return false;
106 }
107
108 static bool mount_is_bind(const MountParameters *p) {
109 assert(p);
110
111 if (fstab_test_option(p->options, "bind\0" "rbind\0"))
112 return true;
113
114 if (p->fstype && STR_IN_SET(p->fstype, "bind", "rbind"))
115 return true;
116
117 return false;
118 }
119
120 static bool mount_is_auto(const MountParameters *p) {
121 assert(p);
122
123 return !fstab_test_option(p->options, "noauto\0");
124 }
125
126 static bool mount_is_automount(const MountParameters *p) {
127 assert(p);
128
129 return fstab_test_option(p->options,
130 "comment=systemd.automount\0"
131 "x-systemd.automount\0");
132 }
133
134 static bool mount_is_bound_to_device(const Mount *m) {
135 const MountParameters *p;
136
137 if (m->from_fragment)
138 return true;
139
140 p = &m->parameters_proc_self_mountinfo;
141 return fstab_test_option(p->options, "x-systemd.device-bound\0");
142 }
143
144 static bool needs_quota(const MountParameters *p) {
145 assert(p);
146
147 /* Quotas are not enabled on network filesystems,
148 * but we want them, for example, on storage connected via iscsi */
149 if (p->fstype && fstype_is_network(p->fstype))
150 return false;
151
152 if (mount_is_bind(p))
153 return false;
154
155 return fstab_test_option(p->options,
156 "usrquota\0" "grpquota\0" "quota\0" "usrjquota\0" "grpjquota\0");
157 }
158
159 const char *mount_get_fstype(const Mount *m) {
160 const char *type = NULL;
161
162 assert(m);
163
164 if (m->from_proc_self_mountinfo && m->parameters_proc_self_mountinfo.fstype)
165 type = m->parameters_proc_self_mountinfo.fstype;
166 else if (m->from_fragment && m->parameters_fragment.fstype)
167 type = m->parameters_fragment.fstype;
168 else
169 type = "";
170
171 return type;
172 }
173
174 static void mount_init(Unit *u) {
175 Mount *m = MOUNT(u);
176
177 assert(u);
178 assert(u->load_state == UNIT_STUB);
179
180 m->timeout_usec = u->manager->default_timeout_start_usec;
181 m->directory_mode = 0755;
182
183 /* We need to make sure that /usr/bin/mount is always called
184 * in the same process group as us, so that the autofs kernel
185 * side doesn't send us another mount request while we are
186 * already trying to comply its last one. */
187 m->exec_context.same_pgrp = true;
188
189 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
190
191 u->ignore_on_isolate = true;
192 }
193
194 static int mount_arm_timer(Mount *m, usec_t usec) {
195 int r;
196
197 assert(m);
198
199 if (m->timer_event_source) {
200 r = sd_event_source_set_time(m->timer_event_source, usec);
201 if (r < 0)
202 return r;
203
204 return sd_event_source_set_enabled(m->timer_event_source, SD_EVENT_ONESHOT);
205 }
206
207 if (usec == USEC_INFINITY)
208 return 0;
209
210 r = sd_event_add_time(
211 UNIT(m)->manager->event,
212 &m->timer_event_source,
213 CLOCK_MONOTONIC,
214 usec, 0,
215 mount_dispatch_timer, m);
216 if (r < 0)
217 return r;
218
219 (void) sd_event_source_set_description(m->timer_event_source, "mount-timer");
220
221 return 0;
222 }
223
224 static void mount_unwatch_control_pid(Mount *m) {
225 assert(m);
226
227 if (m->control_pid <= 0)
228 return;
229
230 unit_unwatch_pid(UNIT(m), m->control_pid);
231 m->control_pid = 0;
232 }
233
234 static void mount_parameters_done(MountParameters *p) {
235 assert(p);
236
237 free(p->what);
238 free(p->options);
239 free(p->fstype);
240
241 p->what = p->options = p->fstype = NULL;
242 }
243
244 static void mount_done(Unit *u) {
245 Mount *m = MOUNT(u);
246
247 assert(m);
248
249 m->where = mfree(m->where);
250
251 mount_parameters_done(&m->parameters_proc_self_mountinfo);
252 mount_parameters_done(&m->parameters_fragment);
253
254 m->exec_runtime = exec_runtime_unref(m->exec_runtime);
255 exec_command_done_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX);
256 m->control_command = NULL;
257
258 dynamic_creds_unref(&m->dynamic_creds);
259
260 mount_unwatch_control_pid(m);
261
262 m->timer_event_source = sd_event_source_unref(m->timer_event_source);
263 }
264
265 _pure_ static MountParameters* get_mount_parameters_fragment(Mount *m) {
266 assert(m);
267
268 if (m->from_fragment)
269 return &m->parameters_fragment;
270
271 return NULL;
272 }
273
274 _pure_ static MountParameters* get_mount_parameters(Mount *m) {
275 assert(m);
276
277 if (m->from_proc_self_mountinfo)
278 return &m->parameters_proc_self_mountinfo;
279
280 return get_mount_parameters_fragment(m);
281 }
282
283 static int mount_add_mount_links(Mount *m) {
284 _cleanup_free_ char *parent = NULL;
285 const char *fstype;
286 MountParameters *pm;
287 Unit *other;
288 Iterator i;
289 Set *s;
290 int r;
291
292 assert(m);
293
294 if (!path_equal(m->where, "/")) {
295 /* Adds in links to other mount points that might lie further
296 * up in the hierarchy */
297
298 parent = dirname_malloc(m->where);
299 if (!parent)
300 return -ENOMEM;
301
302 r = unit_require_mounts_for(UNIT(m), parent);
303 if (r < 0)
304 return r;
305 }
306
307 /* Adds in links to other mount points that might be needed
308 * for the source path (if this is a bind mount or a loop mount) to be
309 * available. */
310 pm = get_mount_parameters_fragment(m);
311 if (pm && pm->what &&
312 path_is_absolute(pm->what) &&
313 (mount_is_bind(pm) || mount_is_loop(pm) || !mount_is_network(pm))) {
314
315 r = unit_require_mounts_for(UNIT(m), pm->what);
316 if (r < 0)
317 return r;
318 }
319
320 /* Adds in links to other units that use this path or paths
321 * further down in the hierarchy */
322 s = manager_get_units_requiring_mounts_for(UNIT(m)->manager, m->where);
323 SET_FOREACH(other, s, i) {
324
325 if (other->load_state != UNIT_LOADED)
326 continue;
327
328 if (other == UNIT(m))
329 continue;
330
331 r = unit_add_dependency(other, UNIT_AFTER, UNIT(m), true);
332 if (r < 0)
333 return r;
334
335 if (UNIT(m)->fragment_path) {
336 /* If we have fragment configuration, then make this dependency required */
337 r = unit_add_dependency(other, UNIT_REQUIRES, UNIT(m), true);
338 if (r < 0)
339 return r;
340 }
341 }
342
343 /* If this is a tmpfs mount then we have to unmount it before we try to deactivate swaps */
344 fstype = mount_get_fstype(m);
345 if (streq(fstype, "tmpfs")) {
346 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_SWAP_TARGET, NULL, true);
347 if (r < 0)
348 return r;
349 }
350
351 return 0;
352 }
353
354 static int mount_add_device_links(Mount *m) {
355 MountParameters *p;
356 bool device_wants_mount = false;
357 UnitDependency dep;
358 int r;
359
360 assert(m);
361
362 p = get_mount_parameters(m);
363 if (!p)
364 return 0;
365
366 if (!p->what)
367 return 0;
368
369 if (mount_is_bind(p))
370 return 0;
371
372 if (!is_device_path(p->what))
373 return 0;
374
375 /* /dev/root is a really weird thing, it's not a real device,
376 * but just a path the kernel exports for the root file system
377 * specified on the kernel command line. Ignore it here. */
378 if (path_equal(p->what, "/dev/root"))
379 return 0;
380
381 if (path_equal(m->where, "/"))
382 return 0;
383
384 if (mount_is_auto(p) && !mount_is_automount(p) && MANAGER_IS_SYSTEM(UNIT(m)->manager))
385 device_wants_mount = true;
386
387 /* Mount units from /proc/self/mountinfo are not bound to devices
388 * by default since they're subject to races when devices are
389 * unplugged. But the user can still force this dep with an
390 * appropriate option (or udev property) so the mount units are
391 * automatically stopped when the device disappears suddenly. */
392 dep = mount_is_bound_to_device(m) ? UNIT_BINDS_TO : UNIT_REQUIRES;
393
394 r = unit_add_node_link(UNIT(m), p->what, device_wants_mount, dep);
395 if (r < 0)
396 return r;
397
398 return 0;
399 }
400
401 static int mount_add_quota_links(Mount *m) {
402 int r;
403 MountParameters *p;
404
405 assert(m);
406
407 if (!MANAGER_IS_SYSTEM(UNIT(m)->manager))
408 return 0;
409
410 p = get_mount_parameters_fragment(m);
411 if (!p)
412 return 0;
413
414 if (!needs_quota(p))
415 return 0;
416
417 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTACHECK_SERVICE, NULL, true);
418 if (r < 0)
419 return r;
420
421 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTAON_SERVICE, NULL, true);
422 if (r < 0)
423 return r;
424
425 return 0;
426 }
427
428 static bool mount_is_extrinsic(Mount *m) {
429 MountParameters *p;
430 assert(m);
431
432 /* Returns true for all units that are "magic" and should be excluded from the usual start-up and shutdown
433 * dependencies. We call them "extrinsic" here, as they are generally mounted outside of the systemd dependency
434 * logic. We shouldn't attempt to manage them ourselves but it's fine if the user operates on them with us. */
435
436 if (!MANAGER_IS_SYSTEM(UNIT(m)->manager)) /* We only automatically manage mounts if we are in system mode */
437 return true;
438
439 if (PATH_IN_SET(m->where, /* Don't bother with the OS data itself */
440 "/",
441 "/usr"))
442 return true;
443
444 if (PATH_STARTSWITH_SET(m->where,
445 "/run/initramfs", /* This should stay around from before we boot until after we shutdown */
446 "/proc", /* All of this is API VFS */
447 "/sys", /* … dito … */
448 "/dev")) /* … dito … */
449 return true;
450
451 /* If this is an initrd mount, and we are not in the initrd, then leave this around forever, too. */
452 p = get_mount_parameters(m);
453 if (p && fstab_test_option(p->options, "x-initrd.mount\0") && !in_initrd())
454 return true;
455
456 return false;
457 }
458
459 static int mount_add_default_dependencies(Mount *m) {
460 MountParameters *p;
461 const char *after;
462 int r;
463
464 assert(m);
465
466 if (!UNIT(m)->default_dependencies)
467 return 0;
468
469 /* We do not add any default dependencies to /, /usr or /run/initramfs/, since they are guaranteed to stay
470 * mounted the whole time, since our system is on it. Also, don't bother with anything mounted below virtual
471 * file systems, it's also going to be virtual, and hence not worth the effort. */
472 if (mount_is_extrinsic(m))
473 return 0;
474
475 p = get_mount_parameters(m);
476 if (!p)
477 return 0;
478
479 if (mount_is_network(p)) {
480 /* We order ourselves after network.target. This is
481 * primarily useful at shutdown: services that take
482 * down the network should order themselves before
483 * network.target, so that they are shut down only
484 * after this mount unit is stopped. */
485
486 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_NETWORK_TARGET, NULL, true);
487 if (r < 0)
488 return r;
489
490 /* We pull in network-online.target, and order
491 * ourselves after it. This is useful at start-up to
492 * actively pull in tools that want to be started
493 * before we start mounting network file systems, and
494 * whose purpose it is to delay this until the network
495 * is "up". */
496
497 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_WANTS, UNIT_AFTER, SPECIAL_NETWORK_ONLINE_TARGET, NULL, true);
498 if (r < 0)
499 return r;
500
501 after = SPECIAL_REMOTE_FS_PRE_TARGET;
502 } else
503 after = SPECIAL_LOCAL_FS_PRE_TARGET;
504
505 r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after, NULL, true);
506 if (r < 0)
507 return r;
508
509 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
510 if (r < 0)
511 return r;
512
513 return 0;
514 }
515
516 static int mount_verify(Mount *m) {
517 _cleanup_free_ char *e = NULL;
518 MountParameters *p;
519 int r;
520
521 assert(m);
522
523 if (UNIT(m)->load_state != UNIT_LOADED)
524 return 0;
525
526 if (!m->from_fragment && !m->from_proc_self_mountinfo && !UNIT(m)->perpetual)
527 return -ENOENT;
528
529 r = unit_name_from_path(m->where, ".mount", &e);
530 if (r < 0)
531 return log_unit_error_errno(UNIT(m), r, "Failed to generate unit name from mount path: %m");
532
533 if (!unit_has_name(UNIT(m), e)) {
534 log_unit_error(UNIT(m), "Where= setting doesn't match unit name. Refusing.");
535 return -EINVAL;
536 }
537
538 if (mount_point_is_api(m->where) || mount_point_ignore(m->where)) {
539 log_unit_error(UNIT(m), "Cannot create mount unit for API file system %s. Refusing.", m->where);
540 return -EINVAL;
541 }
542
543 p = get_mount_parameters_fragment(m);
544 if (p && !p->what) {
545 log_unit_error(UNIT(m), "What= setting is missing. Refusing.");
546 return -EBADMSG;
547 }
548
549 if (m->exec_context.pam_name && m->kill_context.kill_mode != KILL_CONTROL_GROUP) {
550 log_unit_error(UNIT(m), "Unit has PAM enabled. Kill mode must be set to control-group'. Refusing.");
551 return -EINVAL;
552 }
553
554 return 0;
555 }
556
557 static int mount_add_extras(Mount *m) {
558 Unit *u = UNIT(m);
559 int r;
560
561 assert(m);
562
563 if (u->fragment_path)
564 m->from_fragment = true;
565
566 if (!m->where) {
567 r = unit_name_to_path(u->id, &m->where);
568 if (r < 0)
569 return r;
570 }
571
572 path_kill_slashes(m->where);
573
574 if (!u->description) {
575 r = unit_set_description(u, m->where);
576 if (r < 0)
577 return r;
578 }
579
580 r = mount_add_device_links(m);
581 if (r < 0)
582 return r;
583
584 r = mount_add_mount_links(m);
585 if (r < 0)
586 return r;
587
588 r = mount_add_quota_links(m);
589 if (r < 0)
590 return r;
591
592 r = unit_patch_contexts(u);
593 if (r < 0)
594 return r;
595
596 r = unit_add_exec_dependencies(u, &m->exec_context);
597 if (r < 0)
598 return r;
599
600 r = unit_set_default_slice(u);
601 if (r < 0)
602 return r;
603
604 r = mount_add_default_dependencies(m);
605 if (r < 0)
606 return r;
607
608 return 0;
609 }
610
611 static int mount_load_root_mount(Unit *u) {
612 assert(u);
613
614 if (!unit_has_name(u, SPECIAL_ROOT_MOUNT))
615 return 0;
616
617 u->perpetual = true;
618 u->default_dependencies = false;
619
620 /* The stdio/kmsg bridge socket is on /, in order to avoid a dep loop, don't use kmsg logging for -.mount */
621 MOUNT(u)->exec_context.std_output = EXEC_OUTPUT_NULL;
622 MOUNT(u)->exec_context.std_input = EXEC_INPUT_NULL;
623
624 if (!u->description)
625 u->description = strdup("Root Mount");
626
627 return 1;
628 }
629
630 static int mount_load(Unit *u) {
631 Mount *m = MOUNT(u);
632 int r;
633
634 assert(u);
635 assert(u->load_state == UNIT_STUB);
636
637 r = mount_load_root_mount(u);
638 if (r < 0)
639 return r;
640
641 if (m->from_proc_self_mountinfo || u->perpetual)
642 r = unit_load_fragment_and_dropin_optional(u);
643 else
644 r = unit_load_fragment_and_dropin(u);
645 if (r < 0)
646 return r;
647
648 /* This is a new unit? Then let's add in some extras */
649 if (u->load_state == UNIT_LOADED) {
650 r = mount_add_extras(m);
651 if (r < 0)
652 return r;
653 }
654
655 return mount_verify(m);
656 }
657
658 static void mount_set_state(Mount *m, MountState state) {
659 MountState old_state;
660 assert(m);
661
662 old_state = m->state;
663 m->state = state;
664
665 if (!MOUNT_STATE_WITH_PROCESS(state)) {
666 m->timer_event_source = sd_event_source_unref(m->timer_event_source);
667 mount_unwatch_control_pid(m);
668 m->control_command = NULL;
669 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
670 }
671
672 if (state != old_state)
673 log_unit_debug(UNIT(m), "Changed %s -> %s", mount_state_to_string(old_state), mount_state_to_string(state));
674
675 unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state], m->reload_result == MOUNT_SUCCESS);
676 }
677
678 static int mount_coldplug(Unit *u) {
679 Mount *m = MOUNT(u);
680 MountState new_state = MOUNT_DEAD;
681 int r;
682
683 assert(m);
684 assert(m->state == MOUNT_DEAD);
685
686 if (m->deserialized_state != m->state)
687 new_state = m->deserialized_state;
688 else if (m->from_proc_self_mountinfo)
689 new_state = MOUNT_MOUNTED;
690
691 if (new_state == m->state)
692 return 0;
693
694 if (m->control_pid > 0 &&
695 pid_is_unwaited(m->control_pid) &&
696 MOUNT_STATE_WITH_PROCESS(new_state)) {
697
698 r = unit_watch_pid(UNIT(m), m->control_pid);
699 if (r < 0)
700 return r;
701
702 r = mount_arm_timer(m, usec_add(u->state_change_timestamp.monotonic, m->timeout_usec));
703 if (r < 0)
704 return r;
705 }
706
707 if (!IN_SET(new_state, MOUNT_DEAD, MOUNT_FAILED))
708 (void) unit_setup_dynamic_creds(u);
709
710 mount_set_state(m, new_state);
711 return 0;
712 }
713
714 static void mount_dump(Unit *u, FILE *f, const char *prefix) {
715 Mount *m = MOUNT(u);
716 MountParameters *p;
717
718 assert(m);
719 assert(f);
720
721 p = get_mount_parameters(m);
722
723 fprintf(f,
724 "%sMount State: %s\n"
725 "%sResult: %s\n"
726 "%sWhere: %s\n"
727 "%sWhat: %s\n"
728 "%sFile System Type: %s\n"
729 "%sOptions: %s\n"
730 "%sFrom /proc/self/mountinfo: %s\n"
731 "%sFrom fragment: %s\n"
732 "%sExtrinsic: %s\n"
733 "%sDirectoryMode: %04o\n"
734 "%sSloppyOptions: %s\n"
735 "%sLazyUnmount: %s\n"
736 "%sForceUnmount: %s\n",
737 prefix, mount_state_to_string(m->state),
738 prefix, mount_result_to_string(m->result),
739 prefix, m->where,
740 prefix, p ? strna(p->what) : "n/a",
741 prefix, p ? strna(p->fstype) : "n/a",
742 prefix, p ? strna(p->options) : "n/a",
743 prefix, yes_no(m->from_proc_self_mountinfo),
744 prefix, yes_no(m->from_fragment),
745 prefix, yes_no(mount_is_extrinsic(m)),
746 prefix, m->directory_mode,
747 prefix, yes_no(m->sloppy_options),
748 prefix, yes_no(m->lazy_unmount),
749 prefix, yes_no(m->force_unmount));
750
751 if (m->control_pid > 0)
752 fprintf(f,
753 "%sControl PID: "PID_FMT"\n",
754 prefix, m->control_pid);
755
756 exec_context_dump(&m->exec_context, f, prefix);
757 kill_context_dump(&m->kill_context, f, prefix);
758 cgroup_context_dump(&m->cgroup_context, f, prefix);
759 }
760
761 static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
762 pid_t pid;
763 int r;
764 ExecParameters exec_params = {
765 .flags = EXEC_APPLY_SANDBOXING|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
766 .stdin_fd = -1,
767 .stdout_fd = -1,
768 .stderr_fd = -1,
769 };
770
771 assert(m);
772 assert(c);
773 assert(_pid);
774
775 (void) unit_realize_cgroup(UNIT(m));
776 if (m->reset_accounting) {
777 (void) unit_reset_cpu_accounting(UNIT(m));
778 (void) unit_reset_ip_accounting(UNIT(m));
779 m->reset_accounting = false;
780 }
781
782 r = unit_setup_exec_runtime(UNIT(m));
783 if (r < 0)
784 return r;
785
786 r = unit_setup_dynamic_creds(UNIT(m));
787 if (r < 0)
788 return r;
789
790 r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec));
791 if (r < 0)
792 return r;
793
794 manager_set_exec_params(UNIT(m)->manager, &exec_params);
795 unit_set_exec_params(UNIT(m), &exec_params);
796
797 r = exec_spawn(UNIT(m),
798 c,
799 &m->exec_context,
800 &exec_params,
801 m->exec_runtime,
802 &m->dynamic_creds,
803 &pid);
804 if (r < 0)
805 return r;
806
807 r = unit_watch_pid(UNIT(m), pid);
808 if (r < 0)
809 /* FIXME: we need to do something here */
810 return r;
811
812 *_pid = pid;
813
814 return 0;
815 }
816
817 static void mount_enter_dead(Mount *m, MountResult f) {
818 assert(m);
819
820 if (m->result == MOUNT_SUCCESS)
821 m->result = f;
822
823 if (m->result != MOUNT_SUCCESS)
824 log_unit_warning(UNIT(m), "Failed with result '%s'.", mount_result_to_string(m->result));
825
826 mount_set_state(m, m->result != MOUNT_SUCCESS ? MOUNT_FAILED : MOUNT_DEAD);
827
828 exec_runtime_destroy(m->exec_runtime);
829 m->exec_runtime = exec_runtime_unref(m->exec_runtime);
830
831 exec_context_destroy_runtime_directory(&m->exec_context, UNIT(m)->manager->prefix[EXEC_DIRECTORY_RUNTIME]);
832
833 unit_unref_uid_gid(UNIT(m), true);
834
835 dynamic_creds_destroy(&m->dynamic_creds);
836 }
837
838 static void mount_enter_mounted(Mount *m, MountResult f) {
839 assert(m);
840
841 if (m->result == MOUNT_SUCCESS)
842 m->result = f;
843
844 mount_set_state(m, MOUNT_MOUNTED);
845 }
846
847 static void mount_enter_dead_or_mounted(Mount *m, MountResult f) {
848 assert(m);
849
850 /* Enter DEAD or MOUNTED state, depending on what the kernel currently says about the mount point. We use this
851 * whenever we executed an operation, so that our internal state reflects what the kernel says again, after all
852 * ultimately we just mirror the kernel's internal state on this. */
853
854 if (m->from_proc_self_mountinfo)
855 mount_enter_mounted(m, f);
856 else
857 mount_enter_dead(m, f);
858 }
859
860 static int state_to_kill_operation(MountState state) {
861 switch (state) {
862
863 case MOUNT_REMOUNTING_SIGTERM:
864 case MOUNT_UNMOUNTING_SIGTERM:
865 return KILL_TERMINATE;
866
867 case MOUNT_REMOUNTING_SIGKILL:
868 case MOUNT_UNMOUNTING_SIGKILL:
869 return KILL_KILL;
870
871 default:
872 return _KILL_OPERATION_INVALID;
873 }
874 }
875
876 static void mount_enter_signal(Mount *m, MountState state, MountResult f) {
877 int r;
878
879 assert(m);
880
881 if (m->result == MOUNT_SUCCESS)
882 m->result = f;
883
884 r = unit_kill_context(
885 UNIT(m),
886 &m->kill_context,
887 state_to_kill_operation(state),
888 -1,
889 m->control_pid,
890 false);
891 if (r < 0)
892 goto fail;
893
894 if (r > 0) {
895 r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec));
896 if (r < 0)
897 goto fail;
898
899 mount_set_state(m, state);
900 } else if (state == MOUNT_REMOUNTING_SIGTERM && m->kill_context.send_sigkill)
901 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_SUCCESS);
902 else if (IN_SET(state, MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL))
903 mount_enter_mounted(m, MOUNT_SUCCESS);
904 else if (state == MOUNT_UNMOUNTING_SIGTERM && m->kill_context.send_sigkill)
905 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_SUCCESS);
906 else
907 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
908
909 return;
910
911 fail:
912 log_unit_warning_errno(UNIT(m), r, "Failed to kill processes: %m");
913 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
914 }
915
916 static void mount_enter_unmounting(Mount *m) {
917 int r;
918
919 assert(m);
920
921 /* Start counting our attempts */
922 if (!IN_SET(m->state,
923 MOUNT_UNMOUNTING,
924 MOUNT_UNMOUNTING_SIGTERM,
925 MOUNT_UNMOUNTING_SIGKILL))
926 m->n_retry_umount = 0;
927
928 m->control_command_id = MOUNT_EXEC_UNMOUNT;
929 m->control_command = m->exec_command + MOUNT_EXEC_UNMOUNT;
930
931 r = exec_command_set(m->control_command, UMOUNT_PATH, m->where, "-c", NULL);
932 if (r >= 0 && m->lazy_unmount)
933 r = exec_command_append(m->control_command, "-l", NULL);
934 if (r >= 0 && m->force_unmount)
935 r = exec_command_append(m->control_command, "-f", NULL);
936 if (r < 0)
937 goto fail;
938
939 mount_unwatch_control_pid(m);
940
941 r = mount_spawn(m, m->control_command, &m->control_pid);
942 if (r < 0)
943 goto fail;
944
945 mount_set_state(m, MOUNT_UNMOUNTING);
946
947 return;
948
949 fail:
950 log_unit_warning_errno(UNIT(m), r, "Failed to run 'umount' task: %m");
951 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
952 }
953
954 static void mount_enter_mounting(Mount *m) {
955 int r;
956 MountParameters *p;
957
958 assert(m);
959
960 m->control_command_id = MOUNT_EXEC_MOUNT;
961 m->control_command = m->exec_command + MOUNT_EXEC_MOUNT;
962
963 r = unit_fail_if_symlink(UNIT(m), m->where);
964 if (r < 0)
965 goto fail;
966
967 (void) mkdir_p_label(m->where, m->directory_mode);
968
969 unit_warn_if_dir_nonempty(UNIT(m), m->where);
970
971 /* Create the source directory for bind-mounts if needed */
972 p = get_mount_parameters_fragment(m);
973 if (p && mount_is_bind(p))
974 (void) mkdir_p_label(p->what, m->directory_mode);
975
976 if (p) {
977 _cleanup_free_ char *opts = NULL;
978
979 r = fstab_filter_options(p->options, "nofail\0" "noauto\0" "auto\0", NULL, NULL, &opts);
980 if (r < 0)
981 goto fail;
982
983 r = exec_command_set(m->control_command, MOUNT_PATH, p->what, m->where, NULL);
984 if (r >= 0 && m->sloppy_options)
985 r = exec_command_append(m->control_command, "-s", NULL);
986 if (r >= 0 && p->fstype)
987 r = exec_command_append(m->control_command, "-t", p->fstype, NULL);
988 if (r >= 0 && !isempty(opts))
989 r = exec_command_append(m->control_command, "-o", opts, NULL);
990 } else
991 r = -ENOENT;
992 if (r < 0)
993 goto fail;
994
995 mount_unwatch_control_pid(m);
996
997 r = mount_spawn(m, m->control_command, &m->control_pid);
998 if (r < 0)
999 goto fail;
1000
1001 mount_set_state(m, MOUNT_MOUNTING);
1002
1003 return;
1004
1005 fail:
1006 log_unit_warning_errno(UNIT(m), r, "Failed to run 'mount' task: %m");
1007 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_RESOURCES);
1008 }
1009
1010 static void mount_set_reload_result(Mount *m, MountResult result) {
1011 assert(m);
1012
1013 /* Only store the first error we encounter */
1014 if (m->reload_result != MOUNT_SUCCESS)
1015 return;
1016
1017 m->reload_result = result;
1018 }
1019
1020 static void mount_enter_remounting(Mount *m) {
1021 int r;
1022 MountParameters *p;
1023
1024 assert(m);
1025
1026 /* Reset reload result when we are about to start a new remount operation */
1027 m->reload_result = MOUNT_SUCCESS;
1028
1029 m->control_command_id = MOUNT_EXEC_REMOUNT;
1030 m->control_command = m->exec_command + MOUNT_EXEC_REMOUNT;
1031
1032 p = get_mount_parameters_fragment(m);
1033 if (p) {
1034 const char *o;
1035
1036 if (p->options)
1037 o = strjoina("remount,", p->options);
1038 else
1039 o = "remount";
1040
1041 r = exec_command_set(m->control_command, MOUNT_PATH,
1042 p->what, m->where,
1043 "-o", o, NULL);
1044 if (r >= 0 && m->sloppy_options)
1045 r = exec_command_append(m->control_command, "-s", NULL);
1046 if (r >= 0 && p->fstype)
1047 r = exec_command_append(m->control_command, "-t", p->fstype, NULL);
1048 } else
1049 r = -ENOENT;
1050 if (r < 0)
1051 goto fail;
1052
1053 mount_unwatch_control_pid(m);
1054
1055 r = mount_spawn(m, m->control_command, &m->control_pid);
1056 if (r < 0)
1057 goto fail;
1058
1059 mount_set_state(m, MOUNT_REMOUNTING);
1060
1061 return;
1062
1063 fail:
1064 log_unit_warning_errno(UNIT(m), r, "Failed to run 'remount' task: %m");
1065 mount_set_reload_result(m, MOUNT_FAILURE_RESOURCES);
1066 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1067 }
1068
1069 static int mount_start(Unit *u) {
1070 Mount *m = MOUNT(u);
1071 int r;
1072
1073 assert(m);
1074
1075 /* We cannot fulfill this request right now, try again later
1076 * please! */
1077 if (IN_SET(m->state,
1078 MOUNT_UNMOUNTING,
1079 MOUNT_UNMOUNTING_SIGTERM,
1080 MOUNT_UNMOUNTING_SIGKILL))
1081 return -EAGAIN;
1082
1083 /* Already on it! */
1084 if (m->state == MOUNT_MOUNTING)
1085 return 0;
1086
1087 assert(IN_SET(m->state, MOUNT_DEAD, MOUNT_FAILED));
1088
1089 r = unit_start_limit_test(u);
1090 if (r < 0) {
1091 mount_enter_dead(m, MOUNT_FAILURE_START_LIMIT_HIT);
1092 return r;
1093 }
1094
1095 r = unit_acquire_invocation_id(u);
1096 if (r < 0)
1097 return r;
1098
1099 m->result = MOUNT_SUCCESS;
1100 m->reload_result = MOUNT_SUCCESS;
1101 m->reset_accounting = true;
1102
1103 mount_enter_mounting(m);
1104 return 1;
1105 }
1106
1107 static int mount_stop(Unit *u) {
1108 Mount *m = MOUNT(u);
1109
1110 assert(m);
1111
1112 switch (m->state) {
1113
1114 case MOUNT_UNMOUNTING:
1115 case MOUNT_UNMOUNTING_SIGKILL:
1116 case MOUNT_UNMOUNTING_SIGTERM:
1117 /* Already on it */
1118 return 0;
1119
1120 case MOUNT_MOUNTING:
1121 case MOUNT_MOUNTING_DONE:
1122 case MOUNT_REMOUNTING:
1123 /* If we are still waiting for /bin/mount, we go directly into kill mode. */
1124 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_SUCCESS);
1125 return 0;
1126
1127 case MOUNT_REMOUNTING_SIGTERM:
1128 /* If we are already waiting for a hung remount, convert this to the matching unmounting state */
1129 mount_set_state(m, MOUNT_UNMOUNTING_SIGTERM);
1130 return 0;
1131
1132 case MOUNT_REMOUNTING_SIGKILL:
1133 /* as above */
1134 mount_set_state(m, MOUNT_UNMOUNTING_SIGKILL);
1135 return 0;
1136
1137 case MOUNT_MOUNTED:
1138 mount_enter_unmounting(m);
1139 return 1;
1140
1141 default:
1142 assert_not_reached("Unexpected state.");
1143 }
1144 }
1145
1146 static int mount_reload(Unit *u) {
1147 Mount *m = MOUNT(u);
1148
1149 assert(m);
1150
1151 if (m->state == MOUNT_MOUNTING_DONE) /* not yet ready to reload, try again */
1152 return -EAGAIN;
1153
1154 assert(m->state == MOUNT_MOUNTED);
1155
1156 mount_enter_remounting(m);
1157
1158 return 1;
1159 }
1160
1161 static int mount_serialize(Unit *u, FILE *f, FDSet *fds) {
1162 Mount *m = MOUNT(u);
1163
1164 assert(m);
1165 assert(f);
1166 assert(fds);
1167
1168 unit_serialize_item(u, f, "state", mount_state_to_string(m->state));
1169 unit_serialize_item(u, f, "result", mount_result_to_string(m->result));
1170 unit_serialize_item(u, f, "reload-result", mount_result_to_string(m->reload_result));
1171
1172 if (m->control_pid > 0)
1173 unit_serialize_item_format(u, f, "control-pid", PID_FMT, m->control_pid);
1174
1175 if (m->control_command_id >= 0)
1176 unit_serialize_item(u, f, "control-command", mount_exec_command_to_string(m->control_command_id));
1177
1178 return 0;
1179 }
1180
1181 static int mount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
1182 Mount *m = MOUNT(u);
1183
1184 assert(u);
1185 assert(key);
1186 assert(value);
1187 assert(fds);
1188
1189 if (streq(key, "state")) {
1190 MountState state;
1191
1192 if ((state = mount_state_from_string(value)) < 0)
1193 log_unit_debug(u, "Failed to parse state value: %s", value);
1194 else
1195 m->deserialized_state = state;
1196 } else if (streq(key, "result")) {
1197 MountResult f;
1198
1199 f = mount_result_from_string(value);
1200 if (f < 0)
1201 log_unit_debug(u, "Failed to parse result value: %s", value);
1202 else if (f != MOUNT_SUCCESS)
1203 m->result = f;
1204
1205 } else if (streq(key, "reload-result")) {
1206 MountResult f;
1207
1208 f = mount_result_from_string(value);
1209 if (f < 0)
1210 log_unit_debug(u, "Failed to parse reload result value: %s", value);
1211 else if (f != MOUNT_SUCCESS)
1212 m->reload_result = f;
1213
1214 } else if (streq(key, "control-pid")) {
1215 pid_t pid;
1216
1217 if (parse_pid(value, &pid) < 0)
1218 log_unit_debug(u, "Failed to parse control-pid value: %s", value);
1219 else
1220 m->control_pid = pid;
1221 } else if (streq(key, "control-command")) {
1222 MountExecCommand id;
1223
1224 id = mount_exec_command_from_string(value);
1225 if (id < 0)
1226 log_unit_debug(u, "Failed to parse exec-command value: %s", value);
1227 else {
1228 m->control_command_id = id;
1229 m->control_command = m->exec_command + id;
1230 }
1231 } else
1232 log_unit_debug(u, "Unknown serialization key: %s", key);
1233
1234 return 0;
1235 }
1236
1237 _pure_ static UnitActiveState mount_active_state(Unit *u) {
1238 assert(u);
1239
1240 return state_translation_table[MOUNT(u)->state];
1241 }
1242
1243 _pure_ static const char *mount_sub_state_to_string(Unit *u) {
1244 assert(u);
1245
1246 return mount_state_to_string(MOUNT(u)->state);
1247 }
1248
1249 _pure_ static bool mount_check_gc(Unit *u) {
1250 Mount *m = MOUNT(u);
1251
1252 assert(m);
1253
1254 return m->from_proc_self_mountinfo;
1255 }
1256
1257 static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
1258 Mount *m = MOUNT(u);
1259 MountResult f;
1260
1261 assert(m);
1262 assert(pid >= 0);
1263
1264 if (pid != m->control_pid)
1265 return;
1266
1267 m->control_pid = 0;
1268
1269 if (is_clean_exit(code, status, EXIT_CLEAN_COMMAND, NULL))
1270 f = MOUNT_SUCCESS;
1271 else if (code == CLD_EXITED)
1272 f = MOUNT_FAILURE_EXIT_CODE;
1273 else if (code == CLD_KILLED)
1274 f = MOUNT_FAILURE_SIGNAL;
1275 else if (code == CLD_DUMPED)
1276 f = MOUNT_FAILURE_CORE_DUMP;
1277 else
1278 assert_not_reached("Unknown code");
1279
1280 if (IN_SET(m->state, MOUNT_REMOUNTING, MOUNT_REMOUNTING_SIGKILL, MOUNT_REMOUNTING_SIGTERM))
1281 mount_set_reload_result(m, f);
1282 else if (m->result == MOUNT_SUCCESS)
1283 m->result = f;
1284
1285 if (m->control_command) {
1286 exec_status_exit(&m->control_command->exec_status, &m->exec_context, pid, code, status);
1287
1288 m->control_command = NULL;
1289 m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID;
1290 }
1291
1292 log_unit_full(u, f == MOUNT_SUCCESS ? LOG_DEBUG : LOG_NOTICE, 0,
1293 "Mount process exited, code=%s status=%i", sigchld_code_to_string(code), status);
1294
1295 /* Note that mount(8) returning and the kernel sending us a mount table change event might happen
1296 * out-of-order. If an operation succeed we assume the kernel will follow soon too and already change into the
1297 * resulting state. If it fails we check if the kernel still knows about the mount. and change state
1298 * accordingly. */
1299
1300 switch (m->state) {
1301
1302 case MOUNT_MOUNTING:
1303 case MOUNT_MOUNTING_DONE:
1304
1305 if (f == MOUNT_SUCCESS || m->from_proc_self_mountinfo)
1306 /* If /bin/mount returned success, or if we see the mount point in /proc/self/mountinfo we are
1307 * happy. If we see the first condition first, we should see the second condition
1308 * immediately after – or /bin/mount lies to us and is broken. */
1309 mount_enter_mounted(m, f);
1310 else
1311 mount_enter_dead(m, f);
1312 break;
1313
1314 case MOUNT_REMOUNTING:
1315 case MOUNT_REMOUNTING_SIGTERM:
1316 case MOUNT_REMOUNTING_SIGKILL:
1317 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1318 break;
1319
1320 case MOUNT_UNMOUNTING:
1321 case MOUNT_UNMOUNTING_SIGKILL:
1322 case MOUNT_UNMOUNTING_SIGTERM:
1323
1324 if (m->from_proc_self_mountinfo) {
1325
1326 /* Still a mount point? If so, let's try again. Most likely there were multiple mount points
1327 * stacked on top of each other. Note that due to the io event priority logic we can be sure
1328 * the new mountinfo is loaded before we process the SIGCHLD for the mount command. */
1329
1330 if (m->n_retry_umount < RETRY_UMOUNT_MAX) {
1331 log_unit_debug(u, "Mount still present, trying again.");
1332 m->n_retry_umount++;
1333 mount_enter_unmounting(m);
1334 } else {
1335 log_unit_debug(u, "Mount still present after %u attempts to unmount, giving up.", m->n_retry_umount);
1336 mount_enter_mounted(m, f);
1337 }
1338 } else
1339 mount_enter_dead(m, f);
1340
1341 break;
1342
1343 default:
1344 assert_not_reached("Uh, control process died at wrong time.");
1345 }
1346
1347 /* Notify clients about changed exit status */
1348 unit_add_to_dbus_queue(u);
1349 }
1350
1351 static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
1352 Mount *m = MOUNT(userdata);
1353
1354 assert(m);
1355 assert(m->timer_event_source == source);
1356
1357 switch (m->state) {
1358
1359 case MOUNT_MOUNTING:
1360 case MOUNT_MOUNTING_DONE:
1361 log_unit_warning(UNIT(m), "Mounting timed out. Terminating.");
1362 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT);
1363 break;
1364
1365 case MOUNT_REMOUNTING:
1366 log_unit_warning(UNIT(m), "Remounting timed out. Killing remount process.");
1367 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1368 mount_enter_signal(m, MOUNT_REMOUNTING_SIGTERM, MOUNT_SUCCESS);
1369 break;
1370
1371 case MOUNT_REMOUNTING_SIGTERM:
1372 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1373
1374 if (m->kill_context.send_sigkill) {
1375 log_unit_warning(UNIT(m), "Remounting timed out. Killing.");
1376 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_SUCCESS);
1377 } else {
1378 log_unit_warning(UNIT(m), "Remounting timed out. Skipping SIGKILL. Ignoring.");
1379 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1380 }
1381 break;
1382
1383 case MOUNT_REMOUNTING_SIGKILL:
1384 mount_set_reload_result(m, MOUNT_FAILURE_TIMEOUT);
1385
1386 log_unit_warning(UNIT(m), "Mount process still around after SIGKILL. Ignoring.");
1387 mount_enter_dead_or_mounted(m, MOUNT_SUCCESS);
1388 break;
1389
1390 case MOUNT_UNMOUNTING:
1391 log_unit_warning(UNIT(m), "Unmounting timed out. Stopping.");
1392 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT);
1393 break;
1394
1395 case MOUNT_UNMOUNTING_SIGTERM:
1396 if (m->kill_context.send_sigkill) {
1397 log_unit_warning(UNIT(m), "Mount process timed out. Killing.");
1398 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_FAILURE_TIMEOUT);
1399 } else {
1400 log_unit_warning(UNIT(m), "Mount process timed out. Skipping SIGKILL. Ignoring.");
1401 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_TIMEOUT);
1402 }
1403 break;
1404
1405 case MOUNT_UNMOUNTING_SIGKILL:
1406 log_unit_warning(UNIT(m), "Mount process still around after SIGKILL. Ignoring.");
1407 mount_enter_dead_or_mounted(m, MOUNT_FAILURE_TIMEOUT);
1408 break;
1409
1410 default:
1411 assert_not_reached("Timeout at wrong time.");
1412 }
1413
1414 return 0;
1415 }
1416
1417 typedef struct {
1418 bool is_mounted;
1419 bool just_mounted;
1420 bool just_changed;
1421 } MountSetupFlags;
1422
1423 static int mount_setup_new_unit(
1424 Unit *u,
1425 const char *what,
1426 const char *where,
1427 const char *options,
1428 const char *fstype,
1429 MountSetupFlags *flags) {
1430
1431 MountParameters *p;
1432
1433 assert(u);
1434 assert(flags);
1435
1436 u->source_path = strdup("/proc/self/mountinfo");
1437 MOUNT(u)->where = strdup(where);
1438 if (!u->source_path || !MOUNT(u)->where)
1439 return -ENOMEM;
1440
1441 /* Make sure to initialize those fields before mount_is_extrinsic(). */
1442 MOUNT(u)->from_proc_self_mountinfo = true;
1443 p = &MOUNT(u)->parameters_proc_self_mountinfo;
1444
1445 p->what = strdup(what);
1446 p->options = strdup(options);
1447 p->fstype = strdup(fstype);
1448 if (!p->what || !p->options || !p->fstype)
1449 return -ENOMEM;
1450
1451 if (!mount_is_extrinsic(MOUNT(u))) {
1452 const char *target;
1453 int r;
1454
1455 target = mount_is_network(p) ? SPECIAL_REMOTE_FS_TARGET : SPECIAL_LOCAL_FS_TARGET;
1456 r = unit_add_dependency_by_name(u, UNIT_BEFORE, target, NULL, true);
1457 if (r < 0)
1458 return r;
1459
1460 r = unit_add_dependency_by_name(u, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
1461 if (r < 0)
1462 return r;
1463 }
1464
1465 unit_add_to_load_queue(u);
1466 flags->is_mounted = true;
1467 flags->just_mounted = true;
1468 flags->just_changed = true;
1469
1470 return 0;
1471 }
1472
1473 static int mount_setup_existing_unit(
1474 Unit *u,
1475 const char *what,
1476 const char *where,
1477 const char *options,
1478 const char *fstype,
1479 MountSetupFlags *flags) {
1480
1481 MountParameters *p;
1482 bool load_extras = false;
1483 int r1, r2, r3;
1484
1485 assert(u);
1486 assert(flags);
1487
1488 if (!MOUNT(u)->where) {
1489 MOUNT(u)->where = strdup(where);
1490 if (!MOUNT(u)->where)
1491 return -ENOMEM;
1492 }
1493
1494 /* Make sure to initialize those fields before mount_is_extrinsic(). */
1495 p = &MOUNT(u)->parameters_proc_self_mountinfo;
1496
1497 r1 = free_and_strdup(&p->what, what);
1498 r2 = free_and_strdup(&p->options, options);
1499 r3 = free_and_strdup(&p->fstype, fstype);
1500 if (r1 < 0 || r2 < 0 || r3 < 0)
1501 return -ENOMEM;
1502
1503 flags->just_changed = r1 > 0 || r2 > 0 || r3 > 0;
1504 flags->is_mounted = true;
1505 flags->just_mounted = !MOUNT(u)->from_proc_self_mountinfo;
1506
1507 MOUNT(u)->from_proc_self_mountinfo = true;
1508
1509 if (!mount_is_extrinsic(MOUNT(u)) && mount_is_network(p)) {
1510 /* _netdev option may have shown up late, or on a
1511 * remount. Add remote-fs dependencies, even though
1512 * local-fs ones may already be there.
1513 *
1514 * Note: due to a current limitation (we don't track
1515 * in the dependency "Set*" objects who created a
1516 * dependency), we can only add deps, never lose them,
1517 * until the next full daemon-reload. */
1518 unit_add_dependency_by_name(u, UNIT_BEFORE, SPECIAL_REMOTE_FS_TARGET, NULL, true);
1519 load_extras = true;
1520 }
1521
1522 if (u->load_state == UNIT_NOT_FOUND) {
1523 u->load_state = UNIT_LOADED;
1524 u->load_error = 0;
1525
1526 /* Load in the extras later on, after we
1527 * finished initialization of the unit */
1528
1529 /* FIXME: since we're going to load the unit later on, why setting load_extras=true ? */
1530 load_extras = true;
1531 flags->just_changed = true;
1532 }
1533
1534 if (load_extras)
1535 return mount_add_extras(MOUNT(u));
1536
1537 return 0;
1538 }
1539
1540 static int mount_setup_unit(
1541 Manager *m,
1542 const char *what,
1543 const char *where,
1544 const char *options,
1545 const char *fstype,
1546 bool set_flags) {
1547
1548 _cleanup_free_ char *e = NULL;
1549 MountSetupFlags flags;
1550 Unit *u;
1551 int r;
1552
1553 assert(m);
1554 assert(what);
1555 assert(where);
1556 assert(options);
1557 assert(fstype);
1558
1559 /* Ignore API mount points. They should never be referenced in
1560 * dependencies ever. */
1561 if (mount_point_is_api(where) || mount_point_ignore(where))
1562 return 0;
1563
1564 if (streq(fstype, "autofs"))
1565 return 0;
1566
1567 /* probably some kind of swap, ignore */
1568 if (!is_path(where))
1569 return 0;
1570
1571 r = unit_name_from_path(where, ".mount", &e);
1572 if (r < 0)
1573 return r;
1574
1575 u = manager_get_unit(m, e);
1576 if (!u) {
1577 /* First time we see this mount point meaning that it's
1578 * not been initiated by a mount unit but rather by the
1579 * sysadmin having called mount(8) directly. */
1580 r = unit_new_for_name(m, sizeof(Mount), e, &u);
1581 if (r < 0)
1582 goto fail;
1583
1584 r = mount_setup_new_unit(u, what, where, options, fstype, &flags);
1585 if (r < 0)
1586 unit_free(u);
1587 } else
1588 r = mount_setup_existing_unit(u, what, where, options, fstype, &flags);
1589
1590 if (r < 0)
1591 goto fail;
1592
1593 if (set_flags) {
1594 MOUNT(u)->is_mounted = flags.is_mounted;
1595 MOUNT(u)->just_mounted = flags.just_mounted;
1596 MOUNT(u)->just_changed = flags.just_changed;
1597 }
1598
1599 if (flags.just_changed)
1600 unit_add_to_dbus_queue(u);
1601
1602 return 0;
1603 fail:
1604 log_warning_errno(r, "Failed to set up mount unit: %m");
1605 return r;
1606 }
1607
1608 static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) {
1609 _cleanup_(mnt_free_tablep) struct libmnt_table *t = NULL;
1610 _cleanup_(mnt_free_iterp) struct libmnt_iter *i = NULL;
1611 int r = 0;
1612
1613 assert(m);
1614
1615 t = mnt_new_table();
1616 if (!t)
1617 return log_oom();
1618
1619 i = mnt_new_iter(MNT_ITER_FORWARD);
1620 if (!i)
1621 return log_oom();
1622
1623 r = mnt_table_parse_mtab(t, NULL);
1624 if (r < 0)
1625 return log_error_errno(r, "Failed to parse /proc/self/mountinfo: %m");
1626
1627 r = 0;
1628 for (;;) {
1629 const char *device, *path, *options, *fstype;
1630 _cleanup_free_ char *d = NULL, *p = NULL;
1631 struct libmnt_fs *fs;
1632 int k;
1633
1634 k = mnt_table_next_fs(t, i, &fs);
1635 if (k == 1)
1636 break;
1637 if (k < 0)
1638 return log_error_errno(k, "Failed to get next entry from /proc/self/mountinfo: %m");
1639
1640 device = mnt_fs_get_source(fs);
1641 path = mnt_fs_get_target(fs);
1642 options = mnt_fs_get_options(fs);
1643 fstype = mnt_fs_get_fstype(fs);
1644
1645 if (!device || !path)
1646 continue;
1647
1648 if (cunescape(device, UNESCAPE_RELAX, &d) < 0)
1649 return log_oom();
1650
1651 if (cunescape(path, UNESCAPE_RELAX, &p) < 0)
1652 return log_oom();
1653
1654 (void) device_found_node(m, d, true, DEVICE_FOUND_MOUNT, set_flags);
1655
1656 k = mount_setup_unit(m, d, p, options, fstype, set_flags);
1657 if (r == 0 && k < 0)
1658 r = k;
1659 }
1660
1661 return r;
1662 }
1663
1664 static void mount_shutdown(Manager *m) {
1665 assert(m);
1666
1667 m->mount_event_source = sd_event_source_unref(m->mount_event_source);
1668
1669 mnt_unref_monitor(m->mount_monitor);
1670 m->mount_monitor = NULL;
1671 }
1672
1673 static int mount_get_timeout(Unit *u, usec_t *timeout) {
1674 Mount *m = MOUNT(u);
1675 usec_t t;
1676 int r;
1677
1678 if (!m->timer_event_source)
1679 return 0;
1680
1681 r = sd_event_source_get_time(m->timer_event_source, &t);
1682 if (r < 0)
1683 return r;
1684 if (t == USEC_INFINITY)
1685 return 0;
1686
1687 *timeout = t;
1688 return 1;
1689 }
1690
1691 static int synthesize_root_mount(Manager *m) {
1692 Unit *u;
1693 int r;
1694
1695 assert(m);
1696
1697 /* Whatever happens, we know for sure that the root directory is around, and cannot go away. Let's
1698 * unconditionally synthesize it here and mark it as perpetual. */
1699
1700 u = manager_get_unit(m, SPECIAL_ROOT_MOUNT);
1701 if (!u) {
1702 r = unit_new_for_name(m, sizeof(Mount), SPECIAL_ROOT_MOUNT, &u);
1703 if (r < 0)
1704 return log_error_errno(r, "Failed to allocate the special " SPECIAL_ROOT_MOUNT " unit: %m");
1705 }
1706
1707 u->perpetual = true;
1708 MOUNT(u)->deserialized_state = MOUNT_MOUNTED;
1709
1710 unit_add_to_load_queue(u);
1711 unit_add_to_dbus_queue(u);
1712
1713 return 0;
1714 }
1715
1716 static bool mount_is_mounted(Mount *m) {
1717 assert(m);
1718
1719 return UNIT(m)->perpetual || m->is_mounted;
1720 }
1721
1722 static void mount_enumerate(Manager *m) {
1723 int r;
1724
1725 assert(m);
1726
1727 r = synthesize_root_mount(m);
1728 if (r < 0)
1729 goto fail;
1730
1731 mnt_init_debug(0);
1732
1733 if (!m->mount_monitor) {
1734 int fd;
1735
1736 m->mount_monitor = mnt_new_monitor();
1737 if (!m->mount_monitor) {
1738 log_oom();
1739 goto fail;
1740 }
1741
1742 r = mnt_monitor_enable_kernel(m->mount_monitor, 1);
1743 if (r < 0) {
1744 log_error_errno(r, "Failed to enable watching of kernel mount events: %m");
1745 goto fail;
1746 }
1747
1748 r = mnt_monitor_enable_userspace(m->mount_monitor, 1, NULL);
1749 if (r < 0) {
1750 log_error_errno(r, "Failed to enable watching of userspace mount events: %m");
1751 goto fail;
1752 }
1753
1754 /* mnt_unref_monitor() will close the fd */
1755 fd = r = mnt_monitor_get_fd(m->mount_monitor);
1756 if (r < 0) {
1757 log_error_errno(r, "Failed to acquire watch file descriptor: %m");
1758 goto fail;
1759 }
1760
1761 r = sd_event_add_io(m->event, &m->mount_event_source, fd, EPOLLIN, mount_dispatch_io, m);
1762 if (r < 0) {
1763 log_error_errno(r, "Failed to watch mount file descriptor: %m");
1764 goto fail;
1765 }
1766
1767 r = sd_event_source_set_priority(m->mount_event_source, -10);
1768 if (r < 0) {
1769 log_error_errno(r, "Failed to adjust mount watch priority: %m");
1770 goto fail;
1771 }
1772
1773 (void) sd_event_source_set_description(m->mount_event_source, "mount-monitor-dispatch");
1774 }
1775
1776 r = mount_load_proc_self_mountinfo(m, false);
1777 if (r < 0)
1778 goto fail;
1779
1780 return;
1781
1782 fail:
1783 mount_shutdown(m);
1784 }
1785
1786 static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
1787 _cleanup_set_free_ Set *around = NULL, *gone = NULL;
1788 Manager *m = userdata;
1789 const char *what;
1790 Iterator i;
1791 Unit *u;
1792 int r;
1793
1794 assert(m);
1795 assert(revents & EPOLLIN);
1796
1797 if (fd == mnt_monitor_get_fd(m->mount_monitor)) {
1798 bool rescan = false;
1799
1800 /* Drain all events and verify that the event is valid.
1801 *
1802 * Note that libmount also monitors /run/mount mkdir if the
1803 * directory does not exist yet. The mkdir may generate event
1804 * which is irrelevant for us.
1805 *
1806 * error: r < 0; valid: r == 0, false positive: rc == 1 */
1807 do {
1808 r = mnt_monitor_next_change(m->mount_monitor, NULL, NULL);
1809 if (r == 0)
1810 rescan = true;
1811 else if (r < 0)
1812 return log_error_errno(r, "Failed to drain libmount events");
1813 } while (r == 0);
1814
1815 log_debug("libmount event [rescan: %s]", yes_no(rescan));
1816 if (!rescan)
1817 return 0;
1818 }
1819
1820 r = mount_load_proc_self_mountinfo(m, true);
1821 if (r < 0) {
1822 /* Reset flags, just in case, for later calls */
1823 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) {
1824 Mount *mount = MOUNT(u);
1825
1826 mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1827 }
1828
1829 return 0;
1830 }
1831
1832 manager_dispatch_load_queue(m);
1833
1834 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) {
1835 Mount *mount = MOUNT(u);
1836
1837 if (!mount_is_mounted(mount)) {
1838
1839 /* A mount point is not around right now. It
1840 * might be gone, or might never have
1841 * existed. */
1842
1843 if (mount->from_proc_self_mountinfo &&
1844 mount->parameters_proc_self_mountinfo.what) {
1845
1846 /* Remember that this device might just have disappeared */
1847 if (set_ensure_allocated(&gone, &string_hash_ops) < 0 ||
1848 set_put(gone, mount->parameters_proc_self_mountinfo.what) < 0)
1849 log_oom(); /* we don't care too much about OOM here... */
1850 }
1851
1852 mount->from_proc_self_mountinfo = false;
1853
1854 switch (mount->state) {
1855
1856 case MOUNT_MOUNTED:
1857 /* This has just been unmounted by
1858 * somebody else, follow the state
1859 * change. */
1860 mount->result = MOUNT_SUCCESS; /* make sure we forget any earlier umount failures */
1861 mount_enter_dead(mount, MOUNT_SUCCESS);
1862 break;
1863
1864 default:
1865 break;
1866 }
1867
1868 } else if (mount->just_mounted || mount->just_changed) {
1869
1870 /* A mount point was added or changed */
1871
1872 switch (mount->state) {
1873
1874 case MOUNT_DEAD:
1875 case MOUNT_FAILED:
1876
1877 /* This has just been mounted by somebody else, follow the state change, but let's
1878 * generate a new invocation ID for this implicitly and automatically. */
1879 (void) unit_acquire_invocation_id(UNIT(mount));
1880 mount_enter_mounted(mount, MOUNT_SUCCESS);
1881 break;
1882
1883 case MOUNT_MOUNTING:
1884 mount_set_state(mount, MOUNT_MOUNTING_DONE);
1885 break;
1886
1887 default:
1888 /* Nothing really changed, but let's
1889 * issue an notification call
1890 * nonetheless, in case somebody is
1891 * waiting for this. (e.g. file system
1892 * ro/rw remounts.) */
1893 mount_set_state(mount, mount->state);
1894 break;
1895 }
1896 }
1897
1898 if (mount_is_mounted(mount) &&
1899 mount->from_proc_self_mountinfo &&
1900 mount->parameters_proc_self_mountinfo.what) {
1901
1902 if (set_ensure_allocated(&around, &string_hash_ops) < 0 ||
1903 set_put(around, mount->parameters_proc_self_mountinfo.what) < 0)
1904 log_oom();
1905 }
1906
1907 /* Reset the flags for later calls */
1908 mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1909 }
1910
1911 SET_FOREACH(what, gone, i) {
1912 if (set_contains(around, what))
1913 continue;
1914
1915 /* Let the device units know that the device is no longer mounted */
1916 (void) device_found_node(m, what, false, DEVICE_FOUND_MOUNT, true);
1917 }
1918
1919 return 0;
1920 }
1921
1922 static void mount_reset_failed(Unit *u) {
1923 Mount *m = MOUNT(u);
1924
1925 assert(m);
1926
1927 if (m->state == MOUNT_FAILED)
1928 mount_set_state(m, MOUNT_DEAD);
1929
1930 m->result = MOUNT_SUCCESS;
1931 m->reload_result = MOUNT_SUCCESS;
1932 }
1933
1934 static int mount_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
1935 Mount *m = MOUNT(u);
1936
1937 assert(m);
1938
1939 return unit_kill_common(u, who, signo, -1, MOUNT(u)->control_pid, error);
1940 }
1941
1942 static int mount_control_pid(Unit *u) {
1943 Mount *m = MOUNT(u);
1944
1945 assert(m);
1946
1947 return m->control_pid;
1948 }
1949
1950 static const char* const mount_exec_command_table[_MOUNT_EXEC_COMMAND_MAX] = {
1951 [MOUNT_EXEC_MOUNT] = "ExecMount",
1952 [MOUNT_EXEC_UNMOUNT] = "ExecUnmount",
1953 [MOUNT_EXEC_REMOUNT] = "ExecRemount",
1954 };
1955
1956 DEFINE_STRING_TABLE_LOOKUP(mount_exec_command, MountExecCommand);
1957
1958 static const char* const mount_result_table[_MOUNT_RESULT_MAX] = {
1959 [MOUNT_SUCCESS] = "success",
1960 [MOUNT_FAILURE_RESOURCES] = "resources",
1961 [MOUNT_FAILURE_TIMEOUT] = "timeout",
1962 [MOUNT_FAILURE_EXIT_CODE] = "exit-code",
1963 [MOUNT_FAILURE_SIGNAL] = "signal",
1964 [MOUNT_FAILURE_CORE_DUMP] = "core-dump",
1965 [MOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1966 };
1967
1968 DEFINE_STRING_TABLE_LOOKUP(mount_result, MountResult);
1969
1970 const UnitVTable mount_vtable = {
1971 .object_size = sizeof(Mount),
1972 .exec_context_offset = offsetof(Mount, exec_context),
1973 .cgroup_context_offset = offsetof(Mount, cgroup_context),
1974 .kill_context_offset = offsetof(Mount, kill_context),
1975 .exec_runtime_offset = offsetof(Mount, exec_runtime),
1976 .dynamic_creds_offset = offsetof(Mount, dynamic_creds),
1977
1978 .sections =
1979 "Unit\0"
1980 "Mount\0"
1981 "Install\0",
1982 .private_section = "Mount",
1983
1984 .init = mount_init,
1985 .load = mount_load,
1986 .done = mount_done,
1987
1988 .coldplug = mount_coldplug,
1989
1990 .dump = mount_dump,
1991
1992 .start = mount_start,
1993 .stop = mount_stop,
1994 .reload = mount_reload,
1995
1996 .kill = mount_kill,
1997
1998 .serialize = mount_serialize,
1999 .deserialize_item = mount_deserialize_item,
2000
2001 .active_state = mount_active_state,
2002 .sub_state_to_string = mount_sub_state_to_string,
2003
2004 .check_gc = mount_check_gc,
2005
2006 .sigchld_event = mount_sigchld_event,
2007
2008 .reset_failed = mount_reset_failed,
2009
2010 .control_pid = mount_control_pid,
2011
2012 .bus_vtable = bus_mount_vtable,
2013 .bus_set_property = bus_mount_set_property,
2014 .bus_commit_properties = bus_mount_commit_properties,
2015
2016 .get_timeout = mount_get_timeout,
2017
2018 .can_transient = true,
2019
2020 .enumerate = mount_enumerate,
2021 .shutdown = mount_shutdown,
2022
2023 .status_message_formats = {
2024 .starting_stopping = {
2025 [0] = "Mounting %s...",
2026 [1] = "Unmounting %s...",
2027 },
2028 .finished_start_job = {
2029 [JOB_DONE] = "Mounted %s.",
2030 [JOB_FAILED] = "Failed to mount %s.",
2031 [JOB_TIMEOUT] = "Timed out mounting %s.",
2032 },
2033 .finished_stop_job = {
2034 [JOB_DONE] = "Unmounted %s.",
2035 [JOB_FAILED] = "Failed unmounting %s.",
2036 [JOB_TIMEOUT] = "Timed out unmounting %s.",
2037 },
2038 },
2039 };
Unnamed repository; edit this file 'description' to name the repository.