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