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[thirdparty/systemd.git] / src / core / swap.c
1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4 #include <sys/epoll.h>
5 #include <sys/stat.h>
6 #include <unistd.h>
7
8 #include "sd-device.h"
9
10 #include "alloc-util.h"
11 #include "dbus-swap.h"
12 #include "dbus-unit.h"
13 #include "device-util.h"
14 #include "device.h"
15 #include "escape.h"
16 #include "exit-status.h"
17 #include "fd-util.h"
18 #include "format-util.h"
19 #include "fstab-util.h"
20 #include "parse-util.h"
21 #include "path-util.h"
22 #include "process-util.h"
23 #include "serialize.h"
24 #include "special.h"
25 #include "string-table.h"
26 #include "string-util.h"
27 #include "swap.h"
28 #include "unit-name.h"
29 #include "unit.h"
30 #include "virt.h"
31
32 static const UnitActiveState state_translation_table[_SWAP_STATE_MAX] = {
33 [SWAP_DEAD] = UNIT_INACTIVE,
34 [SWAP_ACTIVATING] = UNIT_ACTIVATING,
35 [SWAP_ACTIVATING_DONE] = UNIT_ACTIVE,
36 [SWAP_ACTIVE] = UNIT_ACTIVE,
37 [SWAP_DEACTIVATING] = UNIT_DEACTIVATING,
38 [SWAP_DEACTIVATING_SIGTERM] = UNIT_DEACTIVATING,
39 [SWAP_DEACTIVATING_SIGKILL] = UNIT_DEACTIVATING,
40 [SWAP_FAILED] = UNIT_FAILED,
41 [SWAP_CLEANING] = UNIT_MAINTENANCE,
42 };
43
44 static int swap_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
45 static int swap_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata);
46 static int swap_process_proc_swaps(Manager *m);
47
48 static bool SWAP_STATE_WITH_PROCESS(SwapState state) {
49 return IN_SET(state,
50 SWAP_ACTIVATING,
51 SWAP_ACTIVATING_DONE,
52 SWAP_DEACTIVATING,
53 SWAP_DEACTIVATING_SIGTERM,
54 SWAP_DEACTIVATING_SIGKILL,
55 SWAP_CLEANING);
56 }
57
58 static UnitActiveState swap_active_state(Unit *u) {
59 assert(u);
60
61 return state_translation_table[SWAP(u)->state];
62 }
63
64 static const char *swap_sub_state_to_string(Unit *u) {
65 assert(u);
66
67 return swap_state_to_string(SWAP(u)->state);
68 }
69
70 static bool swap_may_gc(Unit *u) {
71 Swap *s = SWAP(u);
72
73 assert(s);
74
75 if (s->from_proc_swaps)
76 return false;
77
78 return true;
79 }
80
81 static bool swap_is_extrinsic(Unit *u) {
82 assert(SWAP(u));
83
84 return MANAGER_IS_USER(u->manager);
85 }
86
87 static void swap_unset_proc_swaps(Swap *s) {
88 assert(s);
89
90 if (!s->from_proc_swaps)
91 return;
92
93 s->parameters_proc_swaps.what = mfree(s->parameters_proc_swaps.what);
94 s->from_proc_swaps = false;
95 }
96
97 static int swap_set_devnode(Swap *s, const char *devnode) {
98 Hashmap *swaps;
99 Swap *first;
100 int r;
101
102 assert(s);
103
104 r = hashmap_ensure_allocated(&UNIT(s)->manager->swaps_by_devnode, &path_hash_ops);
105 if (r < 0)
106 return r;
107
108 swaps = UNIT(s)->manager->swaps_by_devnode;
109
110 if (s->devnode) {
111 first = hashmap_get(swaps, s->devnode);
112
113 LIST_REMOVE(same_devnode, first, s);
114 if (first)
115 hashmap_replace(swaps, first->devnode, first);
116 else
117 hashmap_remove(swaps, s->devnode);
118
119 s->devnode = mfree(s->devnode);
120 }
121
122 if (devnode) {
123 s->devnode = strdup(devnode);
124 if (!s->devnode)
125 return -ENOMEM;
126
127 first = hashmap_get(swaps, s->devnode);
128 LIST_PREPEND(same_devnode, first, s);
129
130 return hashmap_replace(swaps, first->devnode, first);
131 }
132
133 return 0;
134 }
135
136 static void swap_init(Unit *u) {
137 Swap *s = SWAP(u);
138
139 assert(s);
140 assert(UNIT(s)->load_state == UNIT_STUB);
141
142 s->timeout_usec = u->manager->default_timeout_start_usec;
143
144 s->exec_context.std_output = u->manager->default_std_output;
145 s->exec_context.std_error = u->manager->default_std_error;
146
147 s->control_pid = PIDREF_NULL;
148 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
149
150 u->ignore_on_isolate = true;
151 }
152
153 static void swap_unwatch_control_pid(Swap *s) {
154 assert(s);
155
156 if (!pidref_is_set(&s->control_pid))
157 return;
158
159 unit_unwatch_pid(UNIT(s), s->control_pid.pid);
160 pidref_done(&s->control_pid);
161 }
162
163 static void swap_done(Unit *u) {
164 Swap *s = SWAP(u);
165
166 assert(s);
167
168 swap_unset_proc_swaps(s);
169 swap_set_devnode(s, NULL);
170
171 s->what = mfree(s->what);
172 s->parameters_fragment.what = mfree(s->parameters_fragment.what);
173 s->parameters_fragment.options = mfree(s->parameters_fragment.options);
174
175 s->exec_runtime = exec_runtime_free(s->exec_runtime);
176 exec_command_done_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
177 s->control_command = NULL;
178
179 swap_unwatch_control_pid(s);
180
181 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
182 }
183
184 static int swap_arm_timer(Swap *s, usec_t usec) {
185 int r;
186
187 assert(s);
188
189 if (s->timer_event_source) {
190 r = sd_event_source_set_time(s->timer_event_source, usec);
191 if (r < 0)
192 return r;
193
194 return sd_event_source_set_enabled(s->timer_event_source, SD_EVENT_ONESHOT);
195 }
196
197 if (usec == USEC_INFINITY)
198 return 0;
199
200 r = sd_event_add_time(
201 UNIT(s)->manager->event,
202 &s->timer_event_source,
203 CLOCK_MONOTONIC,
204 usec, 0,
205 swap_dispatch_timer, s);
206 if (r < 0)
207 return r;
208
209 (void) sd_event_source_set_description(s->timer_event_source, "swap-timer");
210
211 return 0;
212 }
213
214 static SwapParameters* swap_get_parameters(Swap *s) {
215 assert(s);
216
217 if (s->from_proc_swaps)
218 return &s->parameters_proc_swaps;
219
220 if (s->from_fragment)
221 return &s->parameters_fragment;
222
223 return NULL;
224 }
225
226 static int swap_add_device_dependencies(Swap *s) {
227 UnitDependencyMask mask;
228 SwapParameters *p;
229 int r;
230
231 assert(s);
232
233 if (!s->what)
234 return 0;
235
236 p = swap_get_parameters(s);
237 if (!p || !p->what)
238 return 0;
239
240 mask = s->from_proc_swaps ? UNIT_DEPENDENCY_PROC_SWAP : UNIT_DEPENDENCY_FILE;
241
242 if (is_device_path(p->what)) {
243 r = unit_add_node_dependency(UNIT(s), p->what, UNIT_REQUIRES, mask);
244 if (r < 0)
245 return r;
246
247 return unit_add_blockdev_dependency(UNIT(s), p->what, mask);
248 }
249
250 /* File based swap devices need to be ordered after systemd-remount-fs.service, since they might need
251 * a writable file system. */
252 return unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, SPECIAL_REMOUNT_FS_SERVICE, true, mask);
253 }
254
255 static int swap_add_default_dependencies(Swap *s) {
256 int r;
257
258 assert(s);
259
260 if (!UNIT(s)->default_dependencies)
261 return 0;
262
263 if (!MANAGER_IS_SYSTEM(UNIT(s)->manager))
264 return 0;
265
266 if (detect_container() > 0)
267 return 0;
268
269 /* swap units generated for the swap dev links are missing the
270 * ordering dep against the swap target. */
271 r = unit_add_dependency_by_name(UNIT(s), UNIT_BEFORE, SPECIAL_SWAP_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
272 if (r < 0)
273 return r;
274
275 return unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, true, UNIT_DEPENDENCY_DEFAULT);
276 }
277
278 static int swap_verify(Swap *s) {
279 _cleanup_free_ char *e = NULL;
280 int r;
281
282 assert(UNIT(s)->load_state == UNIT_LOADED);
283
284 r = unit_name_from_path(s->what, ".swap", &e);
285 if (r < 0)
286 return log_unit_error_errno(UNIT(s), r, "Failed to generate unit name from path: %m");
287
288 if (!unit_has_name(UNIT(s), e))
289 return log_unit_error_errno(UNIT(s), SYNTHETIC_ERRNO(ENOEXEC), "Value of What= and unit name do not match, not loading.");
290
291 if (s->exec_context.pam_name && s->kill_context.kill_mode != KILL_CONTROL_GROUP)
292 return log_unit_error_errno(UNIT(s), SYNTHETIC_ERRNO(ENOEXEC), "Unit has PAM enabled. Kill mode must be set to 'control-group'. Refusing to load.");
293
294 return 0;
295 }
296
297 static int swap_load_devnode(Swap *s) {
298 _cleanup_free_ char *p = NULL;
299 struct stat st;
300 int r;
301
302 assert(s);
303
304 if (stat(s->what, &st) < 0 || !S_ISBLK(st.st_mode))
305 return 0;
306
307 r = devname_from_stat_rdev(&st, &p);
308 if (r < 0) {
309 log_unit_full_errno(UNIT(s), r == -ENOENT ? LOG_DEBUG : LOG_WARNING, r,
310 "Failed to get device node for swap %s: %m", s->what);
311 return 0;
312 }
313
314 return swap_set_devnode(s, p);
315 }
316
317 static int swap_add_extras(Swap *s) {
318 int r;
319
320 assert(s);
321
322 if (UNIT(s)->fragment_path)
323 s->from_fragment = true;
324
325 if (!s->what) {
326 if (s->parameters_fragment.what)
327 s->what = strdup(s->parameters_fragment.what);
328 else if (s->parameters_proc_swaps.what)
329 s->what = strdup(s->parameters_proc_swaps.what);
330 else {
331 r = unit_name_to_path(UNIT(s)->id, &s->what);
332 if (r < 0)
333 return r;
334 }
335
336 if (!s->what)
337 return -ENOMEM;
338 }
339
340 path_simplify(s->what);
341
342 if (!UNIT(s)->description) {
343 r = unit_set_description(UNIT(s), s->what);
344 if (r < 0)
345 return r;
346 }
347
348 r = unit_require_mounts_for(UNIT(s), s->what, UNIT_DEPENDENCY_IMPLICIT);
349 if (r < 0)
350 return r;
351
352 r = swap_add_device_dependencies(s);
353 if (r < 0)
354 return r;
355
356 r = swap_load_devnode(s);
357 if (r < 0)
358 return r;
359
360 r = unit_patch_contexts(UNIT(s));
361 if (r < 0)
362 return r;
363
364 r = unit_add_exec_dependencies(UNIT(s), &s->exec_context);
365 if (r < 0)
366 return r;
367
368 r = unit_set_default_slice(UNIT(s));
369 if (r < 0)
370 return r;
371
372 r = swap_add_default_dependencies(s);
373 if (r < 0)
374 return r;
375
376 return 0;
377 }
378
379 static int swap_load(Unit *u) {
380 Swap *s = SWAP(u);
381 int r, q = 0;
382
383 assert(s);
384 assert(u->load_state == UNIT_STUB);
385
386 /* Load a .swap file */
387 bool fragment_optional = s->from_proc_swaps;
388 r = unit_load_fragment_and_dropin(u, !fragment_optional);
389
390 /* Add in some extras, and do so either when we successfully loaded something or when /proc/swaps is
391 * already active. */
392 if (u->load_state == UNIT_LOADED || s->from_proc_swaps)
393 q = swap_add_extras(s);
394
395 if (r < 0)
396 return r;
397 if (q < 0)
398 return q;
399 if (u->load_state != UNIT_LOADED)
400 return 0;
401
402 return swap_verify(s);
403 }
404
405 static int swap_setup_unit(
406 Manager *m,
407 const char *what,
408 const char *what_proc_swaps,
409 int priority,
410 bool set_flags) {
411
412 _cleanup_free_ char *e = NULL;
413 bool delete = false;
414 Unit *u = NULL;
415 int r;
416 SwapParameters *p;
417
418 assert(m);
419 assert(what);
420 assert(what_proc_swaps);
421
422 r = unit_name_from_path(what, ".swap", &e);
423 if (r < 0)
424 return log_unit_error_errno(u, r, "Failed to generate unit name from path: %m");
425
426 u = manager_get_unit(m, e);
427 if (u &&
428 SWAP(u)->from_proc_swaps &&
429 !path_equal(SWAP(u)->parameters_proc_swaps.what, what_proc_swaps))
430 return log_error_errno(SYNTHETIC_ERRNO(EEXIST),
431 "Swap %s appeared twice with different device paths %s and %s",
432 e, SWAP(u)->parameters_proc_swaps.what, what_proc_swaps);
433
434 if (!u) {
435 delete = true;
436
437 r = unit_new_for_name(m, sizeof(Swap), e, &u);
438 if (r < 0)
439 goto fail;
440
441 SWAP(u)->what = strdup(what);
442 if (!SWAP(u)->what) {
443 r = -ENOMEM;
444 goto fail;
445 }
446
447 unit_add_to_load_queue(u);
448 } else
449 delete = false;
450
451 p = &SWAP(u)->parameters_proc_swaps;
452
453 if (!p->what) {
454 p->what = strdup(what_proc_swaps);
455 if (!p->what) {
456 r = -ENOMEM;
457 goto fail;
458 }
459 }
460
461 /* The unit is definitely around now, mark it as loaded if it was previously referenced but could not be
462 * loaded. After all we can load it now, from the data in /proc/swaps. */
463 if (IN_SET(u->load_state, UNIT_NOT_FOUND, UNIT_BAD_SETTING, UNIT_ERROR)) {
464 u->load_state = UNIT_LOADED;
465 u->load_error = 0;
466 }
467
468 if (set_flags) {
469 SWAP(u)->is_active = true;
470 SWAP(u)->just_activated = !SWAP(u)->from_proc_swaps;
471 }
472
473 SWAP(u)->from_proc_swaps = true;
474
475 p->priority = priority;
476 p->priority_set = true;
477
478 unit_add_to_dbus_queue(u);
479 return 0;
480
481 fail:
482 log_unit_warning_errno(u, r, "Failed to load swap unit: %m");
483
484 if (delete)
485 unit_free(u);
486
487 return r;
488 }
489
490 static void swap_process_new(Manager *m, const char *device, int prio, bool set_flags) {
491 _cleanup_(sd_device_unrefp) sd_device *d = NULL;
492 const char *dn;
493 struct stat st, st_link;
494 int r;
495
496 assert(m);
497
498 if (swap_setup_unit(m, device, device, prio, set_flags) < 0)
499 return;
500
501 /* If this is a block device, then let's add duplicates for
502 * all other names of this block device */
503 if (stat(device, &st) < 0 || !S_ISBLK(st.st_mode))
504 return;
505
506 r = sd_device_new_from_stat_rdev(&d, &st);
507 if (r < 0)
508 return (void) log_full_errno(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, r,
509 "Failed to allocate device for swap %s: %m", device);
510
511 /* Add the main device node */
512 if (sd_device_get_devname(d, &dn) >= 0 && !streq(dn, device))
513 (void) swap_setup_unit(m, dn, device, prio, set_flags);
514
515 /* Add additional units for all symlinks */
516 FOREACH_DEVICE_DEVLINK(d, devlink) {
517
518 /* Don't bother with the /dev/block links */
519 if (streq(devlink, device))
520 continue;
521
522 if (path_startswith(devlink, "/dev/block/"))
523 continue;
524
525 if (stat(devlink, &st_link) >= 0 &&
526 (!S_ISBLK(st_link.st_mode) ||
527 st_link.st_rdev != st.st_rdev))
528 continue;
529
530 (void) swap_setup_unit(m, devlink, device, prio, set_flags);
531 }
532 }
533
534 static void swap_set_state(Swap *s, SwapState state) {
535 SwapState old_state;
536
537 assert(s);
538
539 if (s->state != state)
540 bus_unit_send_pending_change_signal(UNIT(s), false);
541
542 old_state = s->state;
543 s->state = state;
544
545 if (!SWAP_STATE_WITH_PROCESS(state)) {
546 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
547 swap_unwatch_control_pid(s);
548 s->control_command = NULL;
549 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
550 }
551
552 if (state != old_state)
553 log_unit_debug(UNIT(s), "Changed %s -> %s", swap_state_to_string(old_state), swap_state_to_string(state));
554
555 unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], /* reload_success = */ true);
556
557 /* If there other units for the same device node have a job
558 queued it might be worth checking again if it is runnable
559 now. This is necessary, since swap_start() refuses
560 operation with EAGAIN if there's already another job for
561 the same device node queued. */
562 LIST_FOREACH_OTHERS(same_devnode, other, s)
563 if (UNIT(other)->job)
564 job_add_to_run_queue(UNIT(other)->job);
565 }
566
567 static int swap_coldplug(Unit *u) {
568 Swap *s = SWAP(u);
569 SwapState new_state = SWAP_DEAD;
570 int r;
571
572 assert(s);
573 assert(s->state == SWAP_DEAD);
574
575 if (s->deserialized_state != s->state)
576 new_state = s->deserialized_state;
577 else if (s->from_proc_swaps)
578 new_state = SWAP_ACTIVE;
579
580 if (new_state == s->state)
581 return 0;
582
583 if (pidref_is_set(&s->control_pid) &&
584 pid_is_unwaited(s->control_pid.pid) &&
585 SWAP_STATE_WITH_PROCESS(new_state)) {
586
587 r = unit_watch_pid(UNIT(s), s->control_pid.pid, /* exclusive= */ false);
588 if (r < 0)
589 return r;
590
591 r = swap_arm_timer(s, usec_add(u->state_change_timestamp.monotonic, s->timeout_usec));
592 if (r < 0)
593 return r;
594 }
595
596 if (!IN_SET(new_state, SWAP_DEAD, SWAP_FAILED))
597 (void) unit_setup_exec_runtime(u);
598
599 swap_set_state(s, new_state);
600 return 0;
601 }
602
603 static void swap_dump(Unit *u, FILE *f, const char *prefix) {
604 Swap *s = SWAP(u);
605 SwapParameters *p;
606
607 assert(s);
608 assert(f);
609
610 if (s->from_proc_swaps)
611 p = &s->parameters_proc_swaps;
612 else if (s->from_fragment)
613 p = &s->parameters_fragment;
614 else
615 p = NULL;
616
617 fprintf(f,
618 "%sSwap State: %s\n"
619 "%sResult: %s\n"
620 "%sClean Result: %s\n"
621 "%sWhat: %s\n"
622 "%sFrom /proc/swaps: %s\n"
623 "%sFrom fragment: %s\n"
624 "%sExtrinsic: %s\n",
625 prefix, swap_state_to_string(s->state),
626 prefix, swap_result_to_string(s->result),
627 prefix, swap_result_to_string(s->clean_result),
628 prefix, s->what,
629 prefix, yes_no(s->from_proc_swaps),
630 prefix, yes_no(s->from_fragment),
631 prefix, yes_no(swap_is_extrinsic(u)));
632
633 if (s->devnode)
634 fprintf(f, "%sDevice Node: %s\n", prefix, s->devnode);
635
636 if (p)
637 fprintf(f,
638 "%sPriority: %i\n"
639 "%sOptions: %s\n",
640 prefix, p->priority,
641 prefix, strempty(p->options));
642
643 fprintf(f,
644 "%sTimeoutSec: %s\n",
645 prefix, FORMAT_TIMESPAN(s->timeout_usec, USEC_PER_SEC));
646
647 if (pidref_is_set(&s->control_pid))
648 fprintf(f,
649 "%sControl PID: "PID_FMT"\n",
650 prefix, s->control_pid.pid);
651
652 exec_context_dump(&s->exec_context, f, prefix);
653 kill_context_dump(&s->kill_context, f, prefix);
654 cgroup_context_dump(UNIT(s), f, prefix);
655 }
656
657 static int swap_spawn(Swap *s, ExecCommand *c, PidRef *ret_pid) {
658
659 _cleanup_(exec_params_clear) ExecParameters exec_params = {
660 .flags = EXEC_APPLY_SANDBOXING|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
661 .stdin_fd = -EBADF,
662 .stdout_fd = -EBADF,
663 .stderr_fd = -EBADF,
664 .exec_fd = -EBADF,
665 };
666 _cleanup_(pidref_done) PidRef pidref = PIDREF_NULL;
667 pid_t pid;
668 int r;
669
670 assert(s);
671 assert(c);
672 assert(ret_pid);
673
674 r = unit_prepare_exec(UNIT(s));
675 if (r < 0)
676 return r;
677
678 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec));
679 if (r < 0)
680 return r;
681
682 r = unit_set_exec_params(UNIT(s), &exec_params);
683 if (r < 0)
684 return r;
685
686 r = exec_spawn(UNIT(s),
687 c,
688 &s->exec_context,
689 &exec_params,
690 s->exec_runtime,
691 &s->cgroup_context,
692 &pid);
693 if (r < 0)
694 return r;
695
696 r = pidref_set_pid(&pidref, pid);
697 if (r < 0)
698 return r;
699
700 r = unit_watch_pid(UNIT(s), pidref.pid, /* exclusive= */ true);
701 if (r < 0)
702 return r;
703
704 *ret_pid = TAKE_PIDREF(pidref);
705 return 0;
706 }
707
708 static void swap_enter_dead(Swap *s, SwapResult f) {
709 assert(s);
710
711 if (s->result == SWAP_SUCCESS)
712 s->result = f;
713
714 unit_log_result(UNIT(s), s->result == SWAP_SUCCESS, swap_result_to_string(s->result));
715 unit_warn_leftover_processes(UNIT(s), unit_log_leftover_process_stop);
716 swap_set_state(s, s->result != SWAP_SUCCESS ? SWAP_FAILED : SWAP_DEAD);
717
718 s->exec_runtime = exec_runtime_destroy(s->exec_runtime);
719
720 unit_destroy_runtime_data(UNIT(s), &s->exec_context);
721
722 unit_unref_uid_gid(UNIT(s), true);
723 }
724
725 static void swap_enter_active(Swap *s, SwapResult f) {
726 assert(s);
727
728 if (s->result == SWAP_SUCCESS)
729 s->result = f;
730
731 swap_set_state(s, SWAP_ACTIVE);
732 }
733
734 static void swap_enter_dead_or_active(Swap *s, SwapResult f) {
735 assert(s);
736
737 if (s->from_proc_swaps) {
738 swap_enter_active(s, f);
739
740 LIST_FOREACH_OTHERS(same_devnode, other, s)
741 if (UNIT(other)->job)
742 swap_enter_dead_or_active(other, f);
743 } else
744 swap_enter_dead(s, f);
745 }
746
747 static int state_to_kill_operation(Swap *s, SwapState state) {
748 if (state == SWAP_DEACTIVATING_SIGTERM) {
749 if (unit_has_job_type(UNIT(s), JOB_RESTART))
750 return KILL_RESTART;
751 else
752 return KILL_TERMINATE;
753 }
754
755 return KILL_KILL;
756 }
757
758 static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
759 int r;
760
761 assert(s);
762
763 if (s->result == SWAP_SUCCESS)
764 s->result = f;
765
766 r = unit_kill_context(UNIT(s),
767 &s->kill_context,
768 state_to_kill_operation(s, state),
769 -1,
770 s->control_pid.pid,
771 false);
772 if (r < 0)
773 goto fail;
774
775 if (r > 0) {
776 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec));
777 if (r < 0)
778 goto fail;
779
780 swap_set_state(s, state);
781 } else if (state == SWAP_DEACTIVATING_SIGTERM && s->kill_context.send_sigkill)
782 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_SUCCESS);
783 else
784 swap_enter_dead_or_active(s, SWAP_SUCCESS);
785
786 return;
787
788 fail:
789 log_unit_warning_errno(UNIT(s), r, "Failed to kill processes: %m");
790 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
791 }
792
793 static void swap_enter_activating(Swap *s) {
794 _cleanup_free_ char *opts = NULL;
795 int r;
796
797 assert(s);
798
799 unit_warn_leftover_processes(UNIT(s), unit_log_leftover_process_start);
800
801 s->control_command_id = SWAP_EXEC_ACTIVATE;
802 s->control_command = s->exec_command + SWAP_EXEC_ACTIVATE;
803
804 if (s->from_fragment) {
805 int priority = 0;
806
807 r = fstab_find_pri(s->parameters_fragment.options, &priority);
808 if (r < 0)
809 log_unit_warning_errno(UNIT(s), r, "Failed to parse swap priority \"%s\", ignoring: %m", s->parameters_fragment.options);
810 else if (r > 0 && s->parameters_fragment.priority_set)
811 log_unit_warning(UNIT(s), "Duplicate swap priority configuration by Priority= and Options= fields.");
812
813 if (r <= 0 && s->parameters_fragment.priority_set) {
814 if (s->parameters_fragment.options)
815 r = asprintf(&opts, "%s,pri=%i", s->parameters_fragment.options, s->parameters_fragment.priority);
816 else
817 r = asprintf(&opts, "pri=%i", s->parameters_fragment.priority);
818 if (r < 0) {
819 r = -ENOMEM;
820 goto fail;
821 }
822 }
823 }
824
825 r = exec_command_set(s->control_command, "/sbin/swapon", "--fixpgsz", NULL);
826 if (r < 0)
827 goto fail;
828
829 if (s->parameters_fragment.options || opts) {
830 r = exec_command_append(s->control_command, "-o",
831 opts ?: s->parameters_fragment.options, NULL);
832 if (r < 0)
833 goto fail;
834 }
835
836 r = exec_command_append(s->control_command, s->what, NULL);
837 if (r < 0)
838 goto fail;
839
840 swap_unwatch_control_pid(s);
841
842 r = swap_spawn(s, s->control_command, &s->control_pid);
843 if (r < 0)
844 goto fail;
845
846 swap_set_state(s, SWAP_ACTIVATING);
847 return;
848
849 fail:
850 log_unit_warning_errno(UNIT(s), r, "Failed to run 'swapon' task: %m");
851 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
852 }
853
854 static void swap_enter_deactivating(Swap *s) {
855 int r;
856
857 assert(s);
858
859 s->control_command_id = SWAP_EXEC_DEACTIVATE;
860 s->control_command = s->exec_command + SWAP_EXEC_DEACTIVATE;
861
862 r = exec_command_set(s->control_command,
863 "/sbin/swapoff",
864 s->what,
865 NULL);
866 if (r < 0)
867 goto fail;
868
869 swap_unwatch_control_pid(s);
870
871 r = swap_spawn(s, s->control_command, &s->control_pid);
872 if (r < 0)
873 goto fail;
874
875 swap_set_state(s, SWAP_DEACTIVATING);
876
877 return;
878
879 fail:
880 log_unit_warning_errno(UNIT(s), r, "Failed to run 'swapoff' task: %m");
881 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
882 }
883
884 static void swap_cycle_clear(Swap *s) {
885 assert(s);
886
887 s->result = SWAP_SUCCESS;
888 exec_command_reset_status_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
889 UNIT(s)->reset_accounting = true;
890 }
891
892 static int swap_start(Unit *u) {
893 Swap *s = SWAP(u);
894 int r;
895
896 assert(s);
897
898 /* We cannot fulfill this request right now, try again later please! */
899 if (IN_SET(s->state,
900 SWAP_DEACTIVATING,
901 SWAP_DEACTIVATING_SIGTERM,
902 SWAP_DEACTIVATING_SIGKILL,
903 SWAP_CLEANING))
904 return -EAGAIN;
905
906 /* Already on it! */
907 if (s->state == SWAP_ACTIVATING)
908 return 0;
909
910 assert(IN_SET(s->state, SWAP_DEAD, SWAP_FAILED));
911
912 if (detect_container() > 0)
913 return -EPERM;
914
915 /* If there's a job for another swap unit for the same node
916 * running, then let's not dispatch this one for now, and wait
917 * until that other job has finished. */
918 LIST_FOREACH_OTHERS(same_devnode, other, s)
919 if (UNIT(other)->job && UNIT(other)->job->state == JOB_RUNNING)
920 return -EAGAIN;
921
922 r = unit_acquire_invocation_id(u);
923 if (r < 0)
924 return r;
925
926 swap_cycle_clear(s);
927 swap_enter_activating(s);
928 return 1;
929 }
930
931 static int swap_stop(Unit *u) {
932 Swap *s = SWAP(u);
933
934 assert(s);
935
936 switch (s->state) {
937
938 case SWAP_DEACTIVATING:
939 case SWAP_DEACTIVATING_SIGTERM:
940 case SWAP_DEACTIVATING_SIGKILL:
941 /* Already on it */
942 return 0;
943
944 case SWAP_ACTIVATING:
945 case SWAP_ACTIVATING_DONE:
946 /* There's a control process pending, directly enter kill mode */
947 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_SUCCESS);
948 return 0;
949
950 case SWAP_ACTIVE:
951 if (detect_container() > 0)
952 return -EPERM;
953
954 swap_enter_deactivating(s);
955 return 1;
956
957 case SWAP_CLEANING:
958 /* If we are currently cleaning, then abort it, brutally. */
959 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_SUCCESS);
960 return 0;
961
962 default:
963 assert_not_reached();
964 }
965 }
966
967 static int swap_serialize(Unit *u, FILE *f, FDSet *fds) {
968 Swap *s = SWAP(u);
969
970 assert(s);
971 assert(f);
972 assert(fds);
973
974 (void) serialize_item(f, "state", swap_state_to_string(s->state));
975 (void) serialize_item(f, "result", swap_result_to_string(s->result));
976
977 if (pidref_is_set(&s->control_pid))
978 (void) serialize_item_format(f, "control-pid", PID_FMT, s->control_pid.pid);
979
980 if (s->control_command_id >= 0)
981 (void) serialize_item(f, "control-command", swap_exec_command_to_string(s->control_command_id));
982
983 return 0;
984 }
985
986 static int swap_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
987 Swap *s = SWAP(u);
988 int r;
989
990 assert(s);
991 assert(fds);
992
993 if (streq(key, "state")) {
994 SwapState state;
995
996 state = swap_state_from_string(value);
997 if (state < 0)
998 log_unit_debug(u, "Failed to parse state value: %s", value);
999 else
1000 s->deserialized_state = state;
1001 } else if (streq(key, "result")) {
1002 SwapResult f;
1003
1004 f = swap_result_from_string(value);
1005 if (f < 0)
1006 log_unit_debug(u, "Failed to parse result value: %s", value);
1007 else if (f != SWAP_SUCCESS)
1008 s->result = f;
1009 } else if (streq(key, "control-pid")) {
1010
1011 pidref_done(&s->control_pid);
1012 r = pidref_set_pidstr(&s->control_pid, value);
1013 if (r < 0)
1014 log_debug_errno(r, "Failed to pin control PID '%s', ignoring: %m", value);
1015
1016 } else if (streq(key, "control-command")) {
1017 SwapExecCommand id;
1018
1019 id = swap_exec_command_from_string(value);
1020 if (id < 0)
1021 log_unit_debug(u, "Failed to parse exec-command value: %s", value);
1022 else {
1023 s->control_command_id = id;
1024 s->control_command = s->exec_command + id;
1025 }
1026 } else
1027 log_unit_debug(u, "Unknown serialization key: %s", key);
1028
1029 return 0;
1030 }
1031
1032 static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
1033 Swap *s = SWAP(u);
1034 SwapResult f;
1035
1036 assert(s);
1037 assert(pid >= 0);
1038
1039 if (pid != s->control_pid.pid)
1040 return;
1041
1042 /* Let's scan /proc/swaps before we process SIGCHLD. For the reasoning see the similar code in
1043 * mount.c */
1044 (void) swap_process_proc_swaps(u->manager);
1045
1046 pidref_done(&s->control_pid);
1047
1048 if (is_clean_exit(code, status, EXIT_CLEAN_COMMAND, NULL))
1049 f = SWAP_SUCCESS;
1050 else if (code == CLD_EXITED)
1051 f = SWAP_FAILURE_EXIT_CODE;
1052 else if (code == CLD_KILLED)
1053 f = SWAP_FAILURE_SIGNAL;
1054 else if (code == CLD_DUMPED)
1055 f = SWAP_FAILURE_CORE_DUMP;
1056 else
1057 assert_not_reached();
1058
1059 if (s->result == SWAP_SUCCESS)
1060 s->result = f;
1061
1062 if (s->control_command) {
1063 exec_status_exit(&s->control_command->exec_status, &s->exec_context, pid, code, status);
1064
1065 s->control_command = NULL;
1066 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
1067 }
1068
1069 unit_log_process_exit(
1070 u,
1071 "Swap process",
1072 swap_exec_command_to_string(s->control_command_id),
1073 f == SWAP_SUCCESS,
1074 code, status);
1075
1076 switch (s->state) {
1077
1078 case SWAP_ACTIVATING:
1079 case SWAP_ACTIVATING_DONE:
1080
1081 if (f == SWAP_SUCCESS || s->from_proc_swaps)
1082 swap_enter_active(s, f);
1083 else
1084 swap_enter_dead(s, f);
1085 break;
1086
1087 case SWAP_DEACTIVATING:
1088 case SWAP_DEACTIVATING_SIGKILL:
1089 case SWAP_DEACTIVATING_SIGTERM:
1090
1091 swap_enter_dead_or_active(s, f);
1092 break;
1093
1094 case SWAP_CLEANING:
1095 if (s->clean_result == SWAP_SUCCESS)
1096 s->clean_result = f;
1097
1098 swap_enter_dead(s, SWAP_SUCCESS);
1099 break;
1100
1101 default:
1102 assert_not_reached();
1103 }
1104
1105 /* Notify clients about changed exit status */
1106 unit_add_to_dbus_queue(u);
1107 }
1108
1109 static int swap_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
1110 Swap *s = SWAP(userdata);
1111
1112 assert(s);
1113 assert(s->timer_event_source == source);
1114
1115 switch (s->state) {
1116
1117 case SWAP_ACTIVATING:
1118 case SWAP_ACTIVATING_DONE:
1119 log_unit_warning(UNIT(s), "Activation timed out. Stopping.");
1120 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
1121 break;
1122
1123 case SWAP_DEACTIVATING:
1124 log_unit_warning(UNIT(s), "Deactivation timed out. Stopping.");
1125 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
1126 break;
1127
1128 case SWAP_DEACTIVATING_SIGTERM:
1129 if (s->kill_context.send_sigkill) {
1130 log_unit_warning(UNIT(s), "Swap process timed out. Killing.");
1131 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
1132 } else {
1133 log_unit_warning(UNIT(s), "Swap process timed out. Skipping SIGKILL. Ignoring.");
1134 swap_enter_dead_or_active(s, SWAP_FAILURE_TIMEOUT);
1135 }
1136 break;
1137
1138 case SWAP_DEACTIVATING_SIGKILL:
1139 log_unit_warning(UNIT(s), "Swap process still around after SIGKILL. Ignoring.");
1140 swap_enter_dead_or_active(s, SWAP_FAILURE_TIMEOUT);
1141 break;
1142
1143 case SWAP_CLEANING:
1144 log_unit_warning(UNIT(s), "Cleaning timed out. killing.");
1145
1146 if (s->clean_result == SWAP_SUCCESS)
1147 s->clean_result = SWAP_FAILURE_TIMEOUT;
1148
1149 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, 0);
1150 break;
1151
1152 default:
1153 assert_not_reached();
1154 }
1155
1156 return 0;
1157 }
1158
1159 static int swap_load_proc_swaps(Manager *m, bool set_flags) {
1160 assert(m);
1161
1162 rewind(m->proc_swaps);
1163
1164 (void) fscanf(m->proc_swaps, "%*s %*s %*s %*s %*s\n");
1165
1166 for (unsigned i = 1;; i++) {
1167 _cleanup_free_ char *dev = NULL, *d = NULL;
1168 int prio = 0, k;
1169
1170 k = fscanf(m->proc_swaps,
1171 "%ms " /* device/file */
1172 "%*s " /* type of swap */
1173 "%*s " /* swap size */
1174 "%*s " /* used */
1175 "%i\n", /* priority */
1176 &dev, &prio);
1177 if (k != 2) {
1178 if (k == EOF)
1179 break;
1180
1181 log_warning("Failed to parse /proc/swaps:%u.", i);
1182 continue;
1183 }
1184
1185 ssize_t l = cunescape(dev, UNESCAPE_RELAX, &d);
1186 if (l < 0)
1187 return log_error_errno(l, "Failed to unescape device path: %m");
1188
1189 device_found_node(m, d, DEVICE_FOUND_SWAP, DEVICE_FOUND_SWAP);
1190
1191 (void) swap_process_new(m, d, prio, set_flags);
1192 }
1193
1194 return 0;
1195 }
1196
1197 static int swap_process_proc_swaps(Manager *m) {
1198 int r;
1199
1200 assert(m);
1201
1202 r = swap_load_proc_swaps(m, true);
1203 if (r < 0) {
1204 log_error_errno(r, "Failed to reread /proc/swaps: %m");
1205
1206 /* Reset flags, just in case, for late calls */
1207 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
1208 Swap *swap = SWAP(u);
1209
1210 assert(swap);
1211
1212 swap->is_active = swap->just_activated = false;
1213 }
1214
1215 return 0;
1216 }
1217
1218 manager_dispatch_load_queue(m);
1219
1220 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
1221 Swap *swap = SWAP(u);
1222
1223 assert(swap);
1224
1225 if (!swap->is_active) {
1226
1227 swap_unset_proc_swaps(swap);
1228
1229 switch (swap->state) {
1230
1231 case SWAP_ACTIVE:
1232 /* This has just been deactivated */
1233 swap_enter_dead(swap, SWAP_SUCCESS);
1234 break;
1235
1236 default:
1237 /* Fire again */
1238 swap_set_state(swap, swap->state);
1239 break;
1240 }
1241
1242 if (swap->what)
1243 device_found_node(m, swap->what, DEVICE_NOT_FOUND, DEVICE_FOUND_SWAP);
1244
1245 } else if (swap->just_activated) {
1246
1247 /* New swap entry */
1248
1249 switch (swap->state) {
1250
1251 case SWAP_DEAD:
1252 case SWAP_FAILED:
1253 (void) unit_acquire_invocation_id(u);
1254 swap_cycle_clear(swap);
1255 swap_enter_active(swap, SWAP_SUCCESS);
1256 break;
1257
1258 case SWAP_ACTIVATING:
1259 swap_set_state(swap, SWAP_ACTIVATING_DONE);
1260 break;
1261
1262 default:
1263 /* Nothing really changed, but let's
1264 * issue an notification call
1265 * nonetheless, in case somebody is
1266 * waiting for this. */
1267 swap_set_state(swap, swap->state);
1268 break;
1269 }
1270 }
1271
1272 /* Reset the flags for later calls */
1273 swap->is_active = swap->just_activated = false;
1274 }
1275
1276 return 1;
1277 }
1278
1279 static int swap_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
1280 Manager *m = ASSERT_PTR(userdata);
1281
1282 assert(revents & EPOLLPRI);
1283
1284 return swap_process_proc_swaps(m);
1285 }
1286
1287 static Unit *swap_following(Unit *u) {
1288 Swap *s = SWAP(u);
1289 Swap *first = NULL;
1290
1291 assert(s);
1292
1293 /* If the user configured the swap through /etc/fstab or
1294 * a device unit, follow that. */
1295
1296 if (s->from_fragment)
1297 return NULL;
1298
1299 LIST_FOREACH_OTHERS(same_devnode, other, s)
1300 if (other->from_fragment)
1301 return UNIT(other);
1302
1303 /* Otherwise, make everybody follow the unit that's named after
1304 * the swap device in the kernel */
1305
1306 if (streq_ptr(s->what, s->devnode))
1307 return NULL;
1308
1309 LIST_FOREACH(same_devnode, other, s->same_devnode_next)
1310 if (streq_ptr(other->what, other->devnode))
1311 return UNIT(other);
1312
1313 LIST_FOREACH_BACKWARDS(same_devnode, other, s->same_devnode_prev) {
1314 if (streq_ptr(other->what, other->devnode))
1315 return UNIT(other);
1316
1317 first = other;
1318 }
1319
1320 /* Fall back to the first on the list */
1321 return UNIT(first);
1322 }
1323
1324 static int swap_following_set(Unit *u, Set **_set) {
1325 Swap *s = SWAP(u);
1326 _cleanup_set_free_ Set *set = NULL;
1327 int r;
1328
1329 assert(s);
1330 assert(_set);
1331
1332 if (LIST_JUST_US(same_devnode, s)) {
1333 *_set = NULL;
1334 return 0;
1335 }
1336
1337 set = set_new(NULL);
1338 if (!set)
1339 return -ENOMEM;
1340
1341 LIST_FOREACH_OTHERS(same_devnode, other, s) {
1342 r = set_put(set, other);
1343 if (r < 0)
1344 return r;
1345 }
1346
1347 *_set = TAKE_PTR(set);
1348 return 1;
1349 }
1350
1351 static void swap_shutdown(Manager *m) {
1352 assert(m);
1353
1354 m->swap_event_source = sd_event_source_disable_unref(m->swap_event_source);
1355 m->proc_swaps = safe_fclose(m->proc_swaps);
1356 m->swaps_by_devnode = hashmap_free(m->swaps_by_devnode);
1357 }
1358
1359 static void swap_enumerate(Manager *m) {
1360 int r;
1361
1362 assert(m);
1363
1364 if (!m->proc_swaps) {
1365 m->proc_swaps = fopen("/proc/swaps", "re");
1366 if (!m->proc_swaps) {
1367 if (errno == ENOENT)
1368 log_debug_errno(errno, "Not swap enabled, skipping enumeration.");
1369 else
1370 log_warning_errno(errno, "Failed to open /proc/swaps, ignoring: %m");
1371
1372 return;
1373 }
1374
1375 r = sd_event_add_io(m->event, &m->swap_event_source, fileno(m->proc_swaps), EPOLLPRI, swap_dispatch_io, m);
1376 if (r < 0) {
1377 log_error_errno(r, "Failed to watch /proc/swaps: %m");
1378 goto fail;
1379 }
1380
1381 /* Dispatch this before we dispatch SIGCHLD, so that
1382 * we always get the events from /proc/swaps before
1383 * the SIGCHLD of /sbin/swapon. */
1384 r = sd_event_source_set_priority(m->swap_event_source, SD_EVENT_PRIORITY_NORMAL-10);
1385 if (r < 0) {
1386 log_error_errno(r, "Failed to change /proc/swaps priority: %m");
1387 goto fail;
1388 }
1389
1390 (void) sd_event_source_set_description(m->swap_event_source, "swap-proc");
1391 }
1392
1393 r = swap_load_proc_swaps(m, false);
1394 if (r < 0)
1395 goto fail;
1396
1397 return;
1398
1399 fail:
1400 swap_shutdown(m);
1401 }
1402
1403 int swap_process_device_new(Manager *m, sd_device *dev) {
1404 _cleanup_free_ char *e = NULL;
1405 const char *dn;
1406 Unit *u;
1407 int r;
1408
1409 assert(m);
1410 assert(dev);
1411
1412 if (sd_device_get_devname(dev, &dn) < 0)
1413 return 0;
1414
1415 r = unit_name_from_path(dn, ".swap", &e);
1416 if (r < 0) {
1417 log_debug_errno(r, "Cannot convert device name '%s' to unit name, ignoring: %m", dn);
1418 return 0;
1419 }
1420
1421 u = manager_get_unit(m, e);
1422 if (u)
1423 r = swap_set_devnode(SWAP(u), dn);
1424
1425 FOREACH_DEVICE_DEVLINK(dev, devlink) {
1426 _cleanup_free_ char *n = NULL;
1427 int q;
1428
1429 q = unit_name_from_path(devlink, ".swap", &n);
1430 if (q == -EINVAL) /* If the name is not convertible to unit name, we can't manage it */
1431 continue;
1432 if (q < 0)
1433 return q;
1434
1435 u = manager_get_unit(m, n);
1436 if (u) {
1437 q = swap_set_devnode(SWAP(u), dn);
1438 if (q < 0)
1439 r = q;
1440 }
1441 }
1442
1443 return r;
1444 }
1445
1446 int swap_process_device_remove(Manager *m, sd_device *dev) {
1447 const char *dn;
1448 int r;
1449 Swap *s;
1450
1451 r = sd_device_get_devname(dev, &dn);
1452 if (r < 0)
1453 return 0;
1454
1455 while ((s = hashmap_get(m->swaps_by_devnode, dn))) {
1456 int q;
1457
1458 q = swap_set_devnode(s, NULL);
1459 if (q < 0)
1460 r = q;
1461 }
1462
1463 return r;
1464 }
1465
1466 static void swap_reset_failed(Unit *u) {
1467 Swap *s = SWAP(u);
1468
1469 assert(s);
1470
1471 if (s->state == SWAP_FAILED)
1472 swap_set_state(s, SWAP_DEAD);
1473
1474 s->result = SWAP_SUCCESS;
1475 s->clean_result = SWAP_SUCCESS;
1476 }
1477
1478 static int swap_kill(Unit *u, KillWho who, int signo, int code, int value, sd_bus_error *error) {
1479 return unit_kill_common(u, who, signo, code, value, -1, SWAP(u)->control_pid.pid, error);
1480 }
1481
1482 static int swap_get_timeout(Unit *u, usec_t *timeout) {
1483 Swap *s = SWAP(u);
1484 usec_t t;
1485 int r;
1486
1487 assert(s);
1488 assert(u);
1489
1490 if (!s->timer_event_source)
1491 return 0;
1492
1493 r = sd_event_source_get_time(s->timer_event_source, &t);
1494 if (r < 0)
1495 return r;
1496 if (t == USEC_INFINITY)
1497 return 0;
1498
1499 *timeout = t;
1500 return 1;
1501 }
1502
1503 static bool swap_supported(void) {
1504 static int supported = -1;
1505
1506 /* If swap support is not available in the kernel, or we are
1507 * running in a container we don't support swap units, and any
1508 * attempts to starting one should fail immediately. */
1509
1510 if (supported < 0)
1511 supported =
1512 access("/proc/swaps", F_OK) >= 0 &&
1513 detect_container() <= 0;
1514
1515 return supported;
1516 }
1517
1518 static int swap_control_pid(Unit *u) {
1519 Swap *s = SWAP(u);
1520
1521 assert(s);
1522
1523 return s->control_pid.pid;
1524 }
1525
1526 static int swap_clean(Unit *u, ExecCleanMask mask) {
1527 _cleanup_strv_free_ char **l = NULL;
1528 Swap *s = SWAP(u);
1529 pid_t pid;
1530 int r;
1531
1532 assert(s);
1533 assert(mask != 0);
1534
1535 if (s->state != SWAP_DEAD)
1536 return -EBUSY;
1537
1538 r = exec_context_get_clean_directories(&s->exec_context, u->manager->prefix, mask, &l);
1539 if (r < 0)
1540 return r;
1541
1542 if (strv_isempty(l))
1543 return -EUNATCH;
1544
1545 swap_unwatch_control_pid(s);
1546 s->clean_result = SWAP_SUCCESS;
1547 s->control_command = NULL;
1548 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
1549
1550 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->exec_context.timeout_clean_usec));
1551 if (r < 0)
1552 goto fail;
1553
1554 r = unit_fork_and_watch_rm_rf(u, l, &pid);
1555 if (r < 0)
1556 goto fail;
1557
1558 r = pidref_set_pid(&s->control_pid, pid);
1559 if (r < 0)
1560 goto fail;
1561
1562 swap_set_state(s, SWAP_CLEANING);
1563 return 0;
1564
1565 fail:
1566 log_unit_warning_errno(u, r, "Failed to initiate cleaning: %m");
1567 s->clean_result = SWAP_FAILURE_RESOURCES;
1568 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
1569 return r;
1570 }
1571
1572 static int swap_can_clean(Unit *u, ExecCleanMask *ret) {
1573 Swap *s = SWAP(u);
1574
1575 assert(s);
1576
1577 return exec_context_get_clean_mask(&s->exec_context, ret);
1578 }
1579
1580 static int swap_can_start(Unit *u) {
1581 Swap *s = SWAP(u);
1582 int r;
1583
1584 assert(s);
1585
1586 r = unit_test_start_limit(u);
1587 if (r < 0) {
1588 swap_enter_dead(s, SWAP_FAILURE_START_LIMIT_HIT);
1589 return r;
1590 }
1591
1592 return 1;
1593 }
1594
1595 static const char* const swap_exec_command_table[_SWAP_EXEC_COMMAND_MAX] = {
1596 [SWAP_EXEC_ACTIVATE] = "ExecActivate",
1597 [SWAP_EXEC_DEACTIVATE] = "ExecDeactivate",
1598 };
1599
1600 DEFINE_STRING_TABLE_LOOKUP(swap_exec_command, SwapExecCommand);
1601
1602 static const char* const swap_result_table[_SWAP_RESULT_MAX] = {
1603 [SWAP_SUCCESS] = "success",
1604 [SWAP_FAILURE_RESOURCES] = "resources",
1605 [SWAP_FAILURE_TIMEOUT] = "timeout",
1606 [SWAP_FAILURE_EXIT_CODE] = "exit-code",
1607 [SWAP_FAILURE_SIGNAL] = "signal",
1608 [SWAP_FAILURE_CORE_DUMP] = "core-dump",
1609 [SWAP_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1610 };
1611
1612 DEFINE_STRING_TABLE_LOOKUP(swap_result, SwapResult);
1613
1614 const UnitVTable swap_vtable = {
1615 .object_size = sizeof(Swap),
1616 .exec_context_offset = offsetof(Swap, exec_context),
1617 .cgroup_context_offset = offsetof(Swap, cgroup_context),
1618 .kill_context_offset = offsetof(Swap, kill_context),
1619 .exec_runtime_offset = offsetof(Swap, exec_runtime),
1620
1621 .sections =
1622 "Unit\0"
1623 "Swap\0"
1624 "Install\0",
1625 .private_section = "Swap",
1626
1627 .can_fail = true,
1628
1629 .init = swap_init,
1630 .load = swap_load,
1631 .done = swap_done,
1632
1633 .coldplug = swap_coldplug,
1634
1635 .dump = swap_dump,
1636
1637 .start = swap_start,
1638 .stop = swap_stop,
1639
1640 .kill = swap_kill,
1641 .clean = swap_clean,
1642 .can_clean = swap_can_clean,
1643
1644 .get_timeout = swap_get_timeout,
1645
1646 .serialize = swap_serialize,
1647 .deserialize_item = swap_deserialize_item,
1648
1649 .active_state = swap_active_state,
1650 .sub_state_to_string = swap_sub_state_to_string,
1651
1652 .will_restart = unit_will_restart_default,
1653
1654 .may_gc = swap_may_gc,
1655 .is_extrinsic = swap_is_extrinsic,
1656
1657 .sigchld_event = swap_sigchld_event,
1658
1659 .reset_failed = swap_reset_failed,
1660
1661 .control_pid = swap_control_pid,
1662
1663 .bus_set_property = bus_swap_set_property,
1664 .bus_commit_properties = bus_swap_commit_properties,
1665
1666 .following = swap_following,
1667 .following_set = swap_following_set,
1668
1669 .enumerate = swap_enumerate,
1670 .shutdown = swap_shutdown,
1671 .supported = swap_supported,
1672
1673 .status_message_formats = {
1674 .starting_stopping = {
1675 [0] = "Activating swap %s...",
1676 [1] = "Deactivating swap %s...",
1677 },
1678 .finished_start_job = {
1679 [JOB_DONE] = "Activated swap %s.",
1680 [JOB_FAILED] = "Failed to activate swap %s.",
1681 [JOB_TIMEOUT] = "Timed out activating swap %s.",
1682 },
1683 .finished_stop_job = {
1684 [JOB_DONE] = "Deactivated swap %s.",
1685 [JOB_FAILED] = "Failed deactivating swap %s.",
1686 [JOB_TIMEOUT] = "Timed out deactivating swap %s.",
1687 },
1688 },
1689
1690 .can_start = swap_can_start,
1691
1692 .notify_plymouth = true,
1693 };