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
SWAP_STATE_WITH_PROCESS(SwapState state)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
swap_active_state(Unit * u)58 _pure_ static UnitActiveState swap_active_state(Unit *u) {
59 assert(u);
60
61 return state_translation_table[SWAP(u)->state];
62 }
63
swap_sub_state_to_string(Unit * u)64 _pure_ 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
swap_may_gc(Unit * u)70 _pure_ 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
swap_is_extrinsic(Unit * u)81 _pure_ static bool swap_is_extrinsic(Unit *u) {
82 assert(SWAP(u));
83
84 return MANAGER_IS_USER(u->manager);
85 }
86
swap_unset_proc_swaps(Swap * s)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
swap_set_devnode(Swap * s,const char * devnode)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
swap_init(Unit * u)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_command_id = _SWAP_EXEC_COMMAND_INVALID;
148
149 u->ignore_on_isolate = true;
150 }
151
swap_unwatch_control_pid(Swap * s)152 static void swap_unwatch_control_pid(Swap *s) {
153 assert(s);
154
155 if (s->control_pid <= 0)
156 return;
157
158 unit_unwatch_pid(UNIT(s), TAKE_PID(s->control_pid));
159 }
160
swap_done(Unit * u)161 static void swap_done(Unit *u) {
162 Swap *s = SWAP(u);
163
164 assert(s);
165
166 swap_unset_proc_swaps(s);
167 swap_set_devnode(s, NULL);
168
169 s->what = mfree(s->what);
170 s->parameters_fragment.what = mfree(s->parameters_fragment.what);
171 s->parameters_fragment.options = mfree(s->parameters_fragment.options);
172
173 s->exec_runtime = exec_runtime_unref(s->exec_runtime, false);
174 exec_command_done_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
175 s->control_command = NULL;
176
177 dynamic_creds_unref(&s->dynamic_creds);
178
179 swap_unwatch_control_pid(s);
180
181 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
182 }
183
swap_arm_timer(Swap * s,usec_t usec)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
swap_get_parameters(Swap * s)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
swap_add_device_dependencies(Swap * s)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
swap_add_default_dependencies(Swap * s)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
swap_verify(Swap * s)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
swap_load_devnode(Swap * s)297 static int swap_load_devnode(Swap *s) {
298 _cleanup_(sd_device_unrefp) sd_device *d = NULL;
299 struct stat st;
300 const char *p;
301 int r;
302
303 assert(s);
304
305 if (stat(s->what, &st) < 0 || !S_ISBLK(st.st_mode))
306 return 0;
307
308 r = sd_device_new_from_stat_rdev(&d, &st);
309 if (r < 0) {
310 log_unit_full_errno(UNIT(s), r == -ENOENT ? LOG_DEBUG : LOG_WARNING, r,
311 "Failed to allocate device for swap %s: %m", s->what);
312 return 0;
313 }
314
315 if (sd_device_get_devname(d, &p) < 0)
316 return 0;
317
318 return swap_set_devnode(s, p);
319 }
320
swap_add_extras(Swap * s)321 static int swap_add_extras(Swap *s) {
322 int r;
323
324 assert(s);
325
326 if (UNIT(s)->fragment_path)
327 s->from_fragment = true;
328
329 if (!s->what) {
330 if (s->parameters_fragment.what)
331 s->what = strdup(s->parameters_fragment.what);
332 else if (s->parameters_proc_swaps.what)
333 s->what = strdup(s->parameters_proc_swaps.what);
334 else {
335 r = unit_name_to_path(UNIT(s)->id, &s->what);
336 if (r < 0)
337 return r;
338 }
339
340 if (!s->what)
341 return -ENOMEM;
342 }
343
344 path_simplify(s->what);
345
346 if (!UNIT(s)->description) {
347 r = unit_set_description(UNIT(s), s->what);
348 if (r < 0)
349 return r;
350 }
351
352 r = unit_require_mounts_for(UNIT(s), s->what, UNIT_DEPENDENCY_IMPLICIT);
353 if (r < 0)
354 return r;
355
356 r = swap_add_device_dependencies(s);
357 if (r < 0)
358 return r;
359
360 r = swap_load_devnode(s);
361 if (r < 0)
362 return r;
363
364 r = unit_patch_contexts(UNIT(s));
365 if (r < 0)
366 return r;
367
368 r = unit_add_exec_dependencies(UNIT(s), &s->exec_context);
369 if (r < 0)
370 return r;
371
372 r = unit_set_default_slice(UNIT(s));
373 if (r < 0)
374 return r;
375
376 r = swap_add_default_dependencies(s);
377 if (r < 0)
378 return r;
379
380 return 0;
381 }
382
swap_load(Unit * u)383 static int swap_load(Unit *u) {
384 Swap *s = SWAP(u);
385 int r, q = 0;
386
387 assert(s);
388 assert(u->load_state == UNIT_STUB);
389
390 /* Load a .swap file */
391 bool fragment_optional = s->from_proc_swaps;
392 r = unit_load_fragment_and_dropin(u, !fragment_optional);
393
394 /* Add in some extras, and do so either when we successfully loaded something or when /proc/swaps is
395 * already active. */
396 if (u->load_state == UNIT_LOADED || s->from_proc_swaps)
397 q = swap_add_extras(s);
398
399 if (r < 0)
400 return r;
401 if (q < 0)
402 return q;
403 if (u->load_state != UNIT_LOADED)
404 return 0;
405
406 return swap_verify(s);
407 }
408
swap_setup_unit(Manager * m,const char * what,const char * what_proc_swaps,int priority,bool set_flags)409 static int swap_setup_unit(
410 Manager *m,
411 const char *what,
412 const char *what_proc_swaps,
413 int priority,
414 bool set_flags) {
415
416 _cleanup_free_ char *e = NULL;
417 bool delete = false;
418 Unit *u = NULL;
419 int r;
420 SwapParameters *p;
421
422 assert(m);
423 assert(what);
424 assert(what_proc_swaps);
425
426 r = unit_name_from_path(what, ".swap", &e);
427 if (r < 0)
428 return log_unit_error_errno(u, r, "Failed to generate unit name from path: %m");
429
430 u = manager_get_unit(m, e);
431 if (u &&
432 SWAP(u)->from_proc_swaps &&
433 !path_equal(SWAP(u)->parameters_proc_swaps.what, what_proc_swaps))
434 return log_error_errno(SYNTHETIC_ERRNO(EEXIST),
435 "Swap %s appeared twice with different device paths %s and %s",
436 e, SWAP(u)->parameters_proc_swaps.what, what_proc_swaps);
437
438 if (!u) {
439 delete = true;
440
441 r = unit_new_for_name(m, sizeof(Swap), e, &u);
442 if (r < 0)
443 goto fail;
444
445 SWAP(u)->what = strdup(what);
446 if (!SWAP(u)->what) {
447 r = -ENOMEM;
448 goto fail;
449 }
450
451 unit_add_to_load_queue(u);
452 } else
453 delete = false;
454
455 p = &SWAP(u)->parameters_proc_swaps;
456
457 if (!p->what) {
458 p->what = strdup(what_proc_swaps);
459 if (!p->what) {
460 r = -ENOMEM;
461 goto fail;
462 }
463 }
464
465 /* The unit is definitely around now, mark it as loaded if it was previously referenced but could not be
466 * loaded. After all we can load it now, from the data in /proc/swaps. */
467 if (IN_SET(u->load_state, UNIT_NOT_FOUND, UNIT_BAD_SETTING, UNIT_ERROR)) {
468 u->load_state = UNIT_LOADED;
469 u->load_error = 0;
470 }
471
472 if (set_flags) {
473 SWAP(u)->is_active = true;
474 SWAP(u)->just_activated = !SWAP(u)->from_proc_swaps;
475 }
476
477 SWAP(u)->from_proc_swaps = true;
478
479 p->priority = priority;
480 p->priority_set = true;
481
482 unit_add_to_dbus_queue(u);
483 return 0;
484
485 fail:
486 log_unit_warning_errno(u, r, "Failed to load swap unit: %m");
487
488 if (delete)
489 unit_free(u);
490
491 return r;
492 }
493
swap_process_new(Manager * m,const char * device,int prio,bool set_flags)494 static void swap_process_new(Manager *m, const char *device, int prio, bool set_flags) {
495 _cleanup_(sd_device_unrefp) sd_device *d = NULL;
496 const char *dn, *devlink;
497 struct stat st, st_link;
498 int r;
499
500 assert(m);
501
502 if (swap_setup_unit(m, device, device, prio, set_flags) < 0)
503 return;
504
505 /* If this is a block device, then let's add duplicates for
506 * all other names of this block device */
507 if (stat(device, &st) < 0 || !S_ISBLK(st.st_mode))
508 return;
509
510 r = sd_device_new_from_stat_rdev(&d, &st);
511 if (r < 0)
512 return (void) log_full_errno(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, r,
513 "Failed to allocate device for swap %s: %m", device);
514
515 /* Add the main device node */
516 if (sd_device_get_devname(d, &dn) >= 0 && !streq(dn, device))
517 (void) swap_setup_unit(m, dn, device, prio, set_flags);
518
519 /* Add additional units for all symlinks */
520 FOREACH_DEVICE_DEVLINK(d, devlink) {
521
522 /* Don't bother with the /dev/block links */
523 if (streq(devlink, device))
524 continue;
525
526 if (path_startswith(devlink, "/dev/block/"))
527 continue;
528
529 if (stat(devlink, &st_link) >= 0 &&
530 (!S_ISBLK(st_link.st_mode) ||
531 st_link.st_rdev != st.st_rdev))
532 continue;
533
534 (void) swap_setup_unit(m, devlink, device, prio, set_flags);
535 }
536 }
537
swap_set_state(Swap * s,SwapState state)538 static void swap_set_state(Swap *s, SwapState state) {
539 SwapState old_state;
540
541 assert(s);
542
543 if (s->state != state)
544 bus_unit_send_pending_change_signal(UNIT(s), false);
545
546 old_state = s->state;
547 s->state = state;
548
549 if (!SWAP_STATE_WITH_PROCESS(state)) {
550 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
551 swap_unwatch_control_pid(s);
552 s->control_command = NULL;
553 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
554 }
555
556 if (state != old_state)
557 log_unit_debug(UNIT(s), "Changed %s -> %s", swap_state_to_string(old_state), swap_state_to_string(state));
558
559 unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], 0);
560
561 /* If there other units for the same device node have a job
562 queued it might be worth checking again if it is runnable
563 now. This is necessary, since swap_start() refuses
564 operation with EAGAIN if there's already another job for
565 the same device node queued. */
566 LIST_FOREACH_OTHERS(same_devnode, other, s)
567 if (UNIT(other)->job)
568 job_add_to_run_queue(UNIT(other)->job);
569 }
570
swap_coldplug(Unit * u)571 static int swap_coldplug(Unit *u) {
572 Swap *s = SWAP(u);
573 SwapState new_state = SWAP_DEAD;
574 int r;
575
576 assert(s);
577 assert(s->state == SWAP_DEAD);
578
579 if (s->deserialized_state != s->state)
580 new_state = s->deserialized_state;
581 else if (s->from_proc_swaps)
582 new_state = SWAP_ACTIVE;
583
584 if (new_state == s->state)
585 return 0;
586
587 if (s->control_pid > 0 &&
588 pid_is_unwaited(s->control_pid) &&
589 SWAP_STATE_WITH_PROCESS(new_state)) {
590
591 r = unit_watch_pid(UNIT(s), s->control_pid, false);
592 if (r < 0)
593 return r;
594
595 r = swap_arm_timer(s, usec_add(u->state_change_timestamp.monotonic, s->timeout_usec));
596 if (r < 0)
597 return r;
598 }
599
600 if (!IN_SET(new_state, SWAP_DEAD, SWAP_FAILED)) {
601 (void) unit_setup_dynamic_creds(u);
602 (void) unit_setup_exec_runtime(u);
603 }
604
605 swap_set_state(s, new_state);
606 return 0;
607 }
608
swap_dump(Unit * u,FILE * f,const char * prefix)609 static void swap_dump(Unit *u, FILE *f, const char *prefix) {
610 Swap *s = SWAP(u);
611 SwapParameters *p;
612
613 assert(s);
614 assert(f);
615
616 if (s->from_proc_swaps)
617 p = &s->parameters_proc_swaps;
618 else if (s->from_fragment)
619 p = &s->parameters_fragment;
620 else
621 p = NULL;
622
623 fprintf(f,
624 "%sSwap State: %s\n"
625 "%sResult: %s\n"
626 "%sClean Result: %s\n"
627 "%sWhat: %s\n"
628 "%sFrom /proc/swaps: %s\n"
629 "%sFrom fragment: %s\n"
630 "%sExtrinsic: %s\n",
631 prefix, swap_state_to_string(s->state),
632 prefix, swap_result_to_string(s->result),
633 prefix, swap_result_to_string(s->clean_result),
634 prefix, s->what,
635 prefix, yes_no(s->from_proc_swaps),
636 prefix, yes_no(s->from_fragment),
637 prefix, yes_no(swap_is_extrinsic(u)));
638
639 if (s->devnode)
640 fprintf(f, "%sDevice Node: %s\n", prefix, s->devnode);
641
642 if (p)
643 fprintf(f,
644 "%sPriority: %i\n"
645 "%sOptions: %s\n",
646 prefix, p->priority,
647 prefix, strempty(p->options));
648
649 fprintf(f,
650 "%sTimeoutSec: %s\n",
651 prefix, FORMAT_TIMESPAN(s->timeout_usec, USEC_PER_SEC));
652
653 if (s->control_pid > 0)
654 fprintf(f,
655 "%sControl PID: "PID_FMT"\n",
656 prefix, s->control_pid);
657
658 exec_context_dump(&s->exec_context, f, prefix);
659 kill_context_dump(&s->kill_context, f, prefix);
660 cgroup_context_dump(UNIT(s), f, prefix);
661 }
662
swap_spawn(Swap * s,ExecCommand * c,pid_t * _pid)663 static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
664
665 _cleanup_(exec_params_clear) ExecParameters exec_params = {
666 .flags = EXEC_APPLY_SANDBOXING|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
667 .stdin_fd = -1,
668 .stdout_fd = -1,
669 .stderr_fd = -1,
670 .exec_fd = -1,
671 };
672 pid_t pid;
673 int r;
674
675 assert(s);
676 assert(c);
677 assert(_pid);
678
679 r = unit_prepare_exec(UNIT(s));
680 if (r < 0)
681 return r;
682
683 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec));
684 if (r < 0)
685 goto fail;
686
687 r = unit_set_exec_params(UNIT(s), &exec_params);
688 if (r < 0)
689 goto fail;
690
691 r = exec_spawn(UNIT(s),
692 c,
693 &s->exec_context,
694 &exec_params,
695 s->exec_runtime,
696 &s->dynamic_creds,
697 &pid);
698 if (r < 0)
699 goto fail;
700
701 r = unit_watch_pid(UNIT(s), pid, true);
702 if (r < 0)
703 goto fail;
704
705 *_pid = pid;
706
707 return 0;
708
709 fail:
710 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
711
712 return r;
713 }
714
swap_enter_dead(Swap * s,SwapResult f)715 static void swap_enter_dead(Swap *s, SwapResult f) {
716 assert(s);
717
718 if (s->result == SWAP_SUCCESS)
719 s->result = f;
720
721 unit_log_result(UNIT(s), s->result == SWAP_SUCCESS, swap_result_to_string(s->result));
722 unit_warn_leftover_processes(UNIT(s), unit_log_leftover_process_stop);
723 swap_set_state(s, s->result != SWAP_SUCCESS ? SWAP_FAILED : SWAP_DEAD);
724
725 s->exec_runtime = exec_runtime_unref(s->exec_runtime, true);
726
727 unit_destroy_runtime_data(UNIT(s), &s->exec_context);
728
729 unit_unref_uid_gid(UNIT(s), true);
730
731 dynamic_creds_destroy(&s->dynamic_creds);
732 }
733
swap_enter_active(Swap * s,SwapResult f)734 static void swap_enter_active(Swap *s, SwapResult f) {
735 assert(s);
736
737 if (s->result == SWAP_SUCCESS)
738 s->result = f;
739
740 swap_set_state(s, SWAP_ACTIVE);
741 }
742
swap_enter_dead_or_active(Swap * s,SwapResult f)743 static void swap_enter_dead_or_active(Swap *s, SwapResult f) {
744 assert(s);
745
746 if (s->from_proc_swaps) {
747 swap_enter_active(s, f);
748
749 LIST_FOREACH_OTHERS(same_devnode, other, s)
750 if (UNIT(other)->job)
751 swap_enter_dead_or_active(other, f);
752 } else
753 swap_enter_dead(s, f);
754 }
755
state_to_kill_operation(Swap * s,SwapState state)756 static int state_to_kill_operation(Swap *s, SwapState state) {
757 if (state == SWAP_DEACTIVATING_SIGTERM) {
758 if (unit_has_job_type(UNIT(s), JOB_RESTART))
759 return KILL_RESTART;
760 else
761 return KILL_TERMINATE;
762 }
763
764 return KILL_KILL;
765 }
766
swap_enter_signal(Swap * s,SwapState state,SwapResult f)767 static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
768 int r;
769
770 assert(s);
771
772 if (s->result == SWAP_SUCCESS)
773 s->result = f;
774
775 r = unit_kill_context(UNIT(s),
776 &s->kill_context,
777 state_to_kill_operation(s, state),
778 -1,
779 s->control_pid,
780 false);
781 if (r < 0)
782 goto fail;
783
784 if (r > 0) {
785 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec));
786 if (r < 0)
787 goto fail;
788
789 swap_set_state(s, state);
790 } else if (state == SWAP_DEACTIVATING_SIGTERM && s->kill_context.send_sigkill)
791 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_SUCCESS);
792 else
793 swap_enter_dead_or_active(s, SWAP_SUCCESS);
794
795 return;
796
797 fail:
798 log_unit_warning_errno(UNIT(s), r, "Failed to kill processes: %m");
799 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
800 }
801
swap_enter_activating(Swap * s)802 static void swap_enter_activating(Swap *s) {
803 _cleanup_free_ char *opts = NULL;
804 int r;
805
806 assert(s);
807
808 unit_warn_leftover_processes(UNIT(s), unit_log_leftover_process_start);
809
810 s->control_command_id = SWAP_EXEC_ACTIVATE;
811 s->control_command = s->exec_command + SWAP_EXEC_ACTIVATE;
812
813 if (s->from_fragment) {
814 int priority = 0;
815
816 r = fstab_find_pri(s->parameters_fragment.options, &priority);
817 if (r < 0)
818 log_unit_warning_errno(UNIT(s), r, "Failed to parse swap priority \"%s\", ignoring: %m", s->parameters_fragment.options);
819 else if (r > 0 && s->parameters_fragment.priority_set)
820 log_unit_warning(UNIT(s), "Duplicate swap priority configuration by Priority= and Options= fields.");
821
822 if (r <= 0 && s->parameters_fragment.priority_set) {
823 if (s->parameters_fragment.options)
824 r = asprintf(&opts, "%s,pri=%i", s->parameters_fragment.options, s->parameters_fragment.priority);
825 else
826 r = asprintf(&opts, "pri=%i", s->parameters_fragment.priority);
827 if (r < 0) {
828 r = -ENOMEM;
829 goto fail;
830 }
831 }
832 }
833
834 r = exec_command_set(s->control_command, "/sbin/swapon", NULL);
835 if (r < 0)
836 goto fail;
837
838 if (s->parameters_fragment.options || opts) {
839 r = exec_command_append(s->control_command, "-o",
840 opts ?: s->parameters_fragment.options, NULL);
841 if (r < 0)
842 goto fail;
843 }
844
845 r = exec_command_append(s->control_command, s->what, NULL);
846 if (r < 0)
847 goto fail;
848
849 swap_unwatch_control_pid(s);
850
851 r = swap_spawn(s, s->control_command, &s->control_pid);
852 if (r < 0)
853 goto fail;
854
855 swap_set_state(s, SWAP_ACTIVATING);
856 return;
857
858 fail:
859 log_unit_warning_errno(UNIT(s), r, "Failed to run 'swapon' task: %m");
860 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
861 }
862
swap_enter_deactivating(Swap * s)863 static void swap_enter_deactivating(Swap *s) {
864 int r;
865
866 assert(s);
867
868 s->control_command_id = SWAP_EXEC_DEACTIVATE;
869 s->control_command = s->exec_command + SWAP_EXEC_DEACTIVATE;
870
871 r = exec_command_set(s->control_command,
872 "/sbin/swapoff",
873 s->what,
874 NULL);
875 if (r < 0)
876 goto fail;
877
878 swap_unwatch_control_pid(s);
879
880 r = swap_spawn(s, s->control_command, &s->control_pid);
881 if (r < 0)
882 goto fail;
883
884 swap_set_state(s, SWAP_DEACTIVATING);
885
886 return;
887
888 fail:
889 log_unit_warning_errno(UNIT(s), r, "Failed to run 'swapoff' task: %m");
890 swap_enter_dead_or_active(s, SWAP_FAILURE_RESOURCES);
891 }
892
swap_cycle_clear(Swap * s)893 static void swap_cycle_clear(Swap *s) {
894 assert(s);
895
896 s->result = SWAP_SUCCESS;
897 exec_command_reset_status_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
898 UNIT(s)->reset_accounting = true;
899 }
900
swap_start(Unit * u)901 static int swap_start(Unit *u) {
902 Swap *s = SWAP(u);
903 int r;
904
905 assert(s);
906
907 /* We cannot fulfill this request right now, try again later please! */
908 if (IN_SET(s->state,
909 SWAP_DEACTIVATING,
910 SWAP_DEACTIVATING_SIGTERM,
911 SWAP_DEACTIVATING_SIGKILL,
912 SWAP_CLEANING))
913 return -EAGAIN;
914
915 /* Already on it! */
916 if (s->state == SWAP_ACTIVATING)
917 return 0;
918
919 assert(IN_SET(s->state, SWAP_DEAD, SWAP_FAILED));
920
921 if (detect_container() > 0)
922 return -EPERM;
923
924 /* If there's a job for another swap unit for the same node
925 * running, then let's not dispatch this one for now, and wait
926 * until that other job has finished. */
927 LIST_FOREACH_OTHERS(same_devnode, other, s)
928 if (UNIT(other)->job && UNIT(other)->job->state == JOB_RUNNING)
929 return -EAGAIN;
930
931 r = unit_acquire_invocation_id(u);
932 if (r < 0)
933 return r;
934
935 swap_cycle_clear(s);
936 swap_enter_activating(s);
937 return 1;
938 }
939
swap_stop(Unit * u)940 static int swap_stop(Unit *u) {
941 Swap *s = SWAP(u);
942
943 assert(s);
944
945 switch (s->state) {
946
947 case SWAP_DEACTIVATING:
948 case SWAP_DEACTIVATING_SIGTERM:
949 case SWAP_DEACTIVATING_SIGKILL:
950 /* Already on it */
951 return 0;
952
953 case SWAP_ACTIVATING:
954 case SWAP_ACTIVATING_DONE:
955 /* There's a control process pending, directly enter kill mode */
956 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_SUCCESS);
957 return 0;
958
959 case SWAP_ACTIVE:
960 if (detect_container() > 0)
961 return -EPERM;
962
963 swap_enter_deactivating(s);
964 return 1;
965
966 case SWAP_CLEANING:
967 /* If we are currently cleaning, then abort it, brutally. */
968 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_SUCCESS);
969 return 0;
970
971 default:
972 assert_not_reached();
973 }
974 }
975
swap_serialize(Unit * u,FILE * f,FDSet * fds)976 static int swap_serialize(Unit *u, FILE *f, FDSet *fds) {
977 Swap *s = SWAP(u);
978
979 assert(s);
980 assert(f);
981 assert(fds);
982
983 (void) serialize_item(f, "state", swap_state_to_string(s->state));
984 (void) serialize_item(f, "result", swap_result_to_string(s->result));
985
986 if (s->control_pid > 0)
987 (void) serialize_item_format(f, "control-pid", PID_FMT, s->control_pid);
988
989 if (s->control_command_id >= 0)
990 (void) serialize_item(f, "control-command", swap_exec_command_to_string(s->control_command_id));
991
992 return 0;
993 }
994
swap_deserialize_item(Unit * u,const char * key,const char * value,FDSet * fds)995 static int swap_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
996 Swap *s = SWAP(u);
997
998 assert(s);
999 assert(fds);
1000
1001 if (streq(key, "state")) {
1002 SwapState state;
1003
1004 state = swap_state_from_string(value);
1005 if (state < 0)
1006 log_unit_debug(u, "Failed to parse state value: %s", value);
1007 else
1008 s->deserialized_state = state;
1009 } else if (streq(key, "result")) {
1010 SwapResult f;
1011
1012 f = swap_result_from_string(value);
1013 if (f < 0)
1014 log_unit_debug(u, "Failed to parse result value: %s", value);
1015 else if (f != SWAP_SUCCESS)
1016 s->result = f;
1017 } else if (streq(key, "control-pid")) {
1018 pid_t pid;
1019
1020 if (parse_pid(value, &pid) < 0)
1021 log_unit_debug(u, "Failed to parse control-pid value: %s", value);
1022 else
1023 s->control_pid = pid;
1024
1025 } else if (streq(key, "control-command")) {
1026 SwapExecCommand id;
1027
1028 id = swap_exec_command_from_string(value);
1029 if (id < 0)
1030 log_unit_debug(u, "Failed to parse exec-command value: %s", value);
1031 else {
1032 s->control_command_id = id;
1033 s->control_command = s->exec_command + id;
1034 }
1035 } else
1036 log_unit_debug(u, "Unknown serialization key: %s", key);
1037
1038 return 0;
1039 }
1040
swap_sigchld_event(Unit * u,pid_t pid,int code,int status)1041 static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
1042 Swap *s = SWAP(u);
1043 SwapResult f;
1044
1045 assert(s);
1046 assert(pid >= 0);
1047
1048 if (pid != s->control_pid)
1049 return;
1050
1051 /* Let's scan /proc/swaps before we process SIGCHLD. For the reasoning see the similar code in
1052 * mount.c */
1053 (void) swap_process_proc_swaps(u->manager);
1054
1055 s->control_pid = 0;
1056
1057 if (is_clean_exit(code, status, EXIT_CLEAN_COMMAND, NULL))
1058 f = SWAP_SUCCESS;
1059 else if (code == CLD_EXITED)
1060 f = SWAP_FAILURE_EXIT_CODE;
1061 else if (code == CLD_KILLED)
1062 f = SWAP_FAILURE_SIGNAL;
1063 else if (code == CLD_DUMPED)
1064 f = SWAP_FAILURE_CORE_DUMP;
1065 else
1066 assert_not_reached();
1067
1068 if (s->result == SWAP_SUCCESS)
1069 s->result = f;
1070
1071 if (s->control_command) {
1072 exec_status_exit(&s->control_command->exec_status, &s->exec_context, pid, code, status);
1073
1074 s->control_command = NULL;
1075 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
1076 }
1077
1078 unit_log_process_exit(
1079 u,
1080 "Swap process",
1081 swap_exec_command_to_string(s->control_command_id),
1082 f == SWAP_SUCCESS,
1083 code, status);
1084
1085 switch (s->state) {
1086
1087 case SWAP_ACTIVATING:
1088 case SWAP_ACTIVATING_DONE:
1089
1090 if (f == SWAP_SUCCESS || s->from_proc_swaps)
1091 swap_enter_active(s, f);
1092 else
1093 swap_enter_dead(s, f);
1094 break;
1095
1096 case SWAP_DEACTIVATING:
1097 case SWAP_DEACTIVATING_SIGKILL:
1098 case SWAP_DEACTIVATING_SIGTERM:
1099
1100 swap_enter_dead_or_active(s, f);
1101 break;
1102
1103 case SWAP_CLEANING:
1104 if (s->clean_result == SWAP_SUCCESS)
1105 s->clean_result = f;
1106
1107 swap_enter_dead(s, SWAP_SUCCESS);
1108 break;
1109
1110 default:
1111 assert_not_reached();
1112 }
1113
1114 /* Notify clients about changed exit status */
1115 unit_add_to_dbus_queue(u);
1116 }
1117
swap_dispatch_timer(sd_event_source * source,usec_t usec,void * userdata)1118 static int swap_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
1119 Swap *s = SWAP(userdata);
1120
1121 assert(s);
1122 assert(s->timer_event_source == source);
1123
1124 switch (s->state) {
1125
1126 case SWAP_ACTIVATING:
1127 case SWAP_ACTIVATING_DONE:
1128 log_unit_warning(UNIT(s), "Activation timed out. Stopping.");
1129 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
1130 break;
1131
1132 case SWAP_DEACTIVATING:
1133 log_unit_warning(UNIT(s), "Deactivation timed out. Stopping.");
1134 swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
1135 break;
1136
1137 case SWAP_DEACTIVATING_SIGTERM:
1138 if (s->kill_context.send_sigkill) {
1139 log_unit_warning(UNIT(s), "Swap process timed out. Killing.");
1140 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
1141 } else {
1142 log_unit_warning(UNIT(s), "Swap process timed out. Skipping SIGKILL. Ignoring.");
1143 swap_enter_dead_or_active(s, SWAP_FAILURE_TIMEOUT);
1144 }
1145 break;
1146
1147 case SWAP_DEACTIVATING_SIGKILL:
1148 log_unit_warning(UNIT(s), "Swap process still around after SIGKILL. Ignoring.");
1149 swap_enter_dead_or_active(s, SWAP_FAILURE_TIMEOUT);
1150 break;
1151
1152 case SWAP_CLEANING:
1153 log_unit_warning(UNIT(s), "Cleaning timed out. killing.");
1154
1155 if (s->clean_result == SWAP_SUCCESS)
1156 s->clean_result = SWAP_FAILURE_TIMEOUT;
1157
1158 swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, 0);
1159 break;
1160
1161 default:
1162 assert_not_reached();
1163 }
1164
1165 return 0;
1166 }
1167
swap_load_proc_swaps(Manager * m,bool set_flags)1168 static int swap_load_proc_swaps(Manager *m, bool set_flags) {
1169 assert(m);
1170
1171 rewind(m->proc_swaps);
1172
1173 (void) fscanf(m->proc_swaps, "%*s %*s %*s %*s %*s\n");
1174
1175 for (unsigned i = 1;; i++) {
1176 _cleanup_free_ char *dev = NULL, *d = NULL;
1177 int prio = 0, k;
1178
1179 k = fscanf(m->proc_swaps,
1180 "%ms " /* device/file */
1181 "%*s " /* type of swap */
1182 "%*s " /* swap size */
1183 "%*s " /* used */
1184 "%i\n", /* priority */
1185 &dev, &prio);
1186 if (k != 2) {
1187 if (k == EOF)
1188 break;
1189
1190 log_warning("Failed to parse /proc/swaps:%u.", i);
1191 continue;
1192 }
1193
1194 ssize_t l = cunescape(dev, UNESCAPE_RELAX, &d);
1195 if (l < 0)
1196 return log_error_errno(l, "Failed to unescape device path: %m");
1197
1198 device_found_node(m, d, DEVICE_FOUND_SWAP, DEVICE_FOUND_SWAP);
1199
1200 (void) swap_process_new(m, d, prio, set_flags);
1201 }
1202
1203 return 0;
1204 }
1205
swap_process_proc_swaps(Manager * m)1206 static int swap_process_proc_swaps(Manager *m) {
1207 int r;
1208
1209 assert(m);
1210
1211 r = swap_load_proc_swaps(m, true);
1212 if (r < 0) {
1213 log_error_errno(r, "Failed to reread /proc/swaps: %m");
1214
1215 /* Reset flags, just in case, for late calls */
1216 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
1217 Swap *swap = SWAP(u);
1218
1219 assert(swap);
1220
1221 swap->is_active = swap->just_activated = false;
1222 }
1223
1224 return 0;
1225 }
1226
1227 manager_dispatch_load_queue(m);
1228
1229 LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
1230 Swap *swap = SWAP(u);
1231
1232 assert(swap);
1233
1234 if (!swap->is_active) {
1235
1236 swap_unset_proc_swaps(swap);
1237
1238 switch (swap->state) {
1239
1240 case SWAP_ACTIVE:
1241 /* This has just been deactivated */
1242 swap_enter_dead(swap, SWAP_SUCCESS);
1243 break;
1244
1245 default:
1246 /* Fire again */
1247 swap_set_state(swap, swap->state);
1248 break;
1249 }
1250
1251 if (swap->what)
1252 device_found_node(m, swap->what, DEVICE_NOT_FOUND, DEVICE_FOUND_SWAP);
1253
1254 } else if (swap->just_activated) {
1255
1256 /* New swap entry */
1257
1258 switch (swap->state) {
1259
1260 case SWAP_DEAD:
1261 case SWAP_FAILED:
1262 (void) unit_acquire_invocation_id(u);
1263 swap_cycle_clear(swap);
1264 swap_enter_active(swap, SWAP_SUCCESS);
1265 break;
1266
1267 case SWAP_ACTIVATING:
1268 swap_set_state(swap, SWAP_ACTIVATING_DONE);
1269 break;
1270
1271 default:
1272 /* Nothing really changed, but let's
1273 * issue an notification call
1274 * nonetheless, in case somebody is
1275 * waiting for this. */
1276 swap_set_state(swap, swap->state);
1277 break;
1278 }
1279 }
1280
1281 /* Reset the flags for later calls */
1282 swap->is_active = swap->just_activated = false;
1283 }
1284
1285 return 1;
1286 }
1287
swap_dispatch_io(sd_event_source * source,int fd,uint32_t revents,void * userdata)1288 static int swap_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
1289 Manager *m = userdata;
1290
1291 assert(m);
1292 assert(revents & EPOLLPRI);
1293
1294 return swap_process_proc_swaps(m);
1295 }
1296
swap_following(Unit * u)1297 static Unit *swap_following(Unit *u) {
1298 Swap *s = SWAP(u);
1299 Swap *first = NULL;
1300
1301 assert(s);
1302
1303 /* If the user configured the swap through /etc/fstab or
1304 * a device unit, follow that. */
1305
1306 if (s->from_fragment)
1307 return NULL;
1308
1309 LIST_FOREACH_OTHERS(same_devnode, other, s)
1310 if (other->from_fragment)
1311 return UNIT(other);
1312
1313 /* Otherwise, make everybody follow the unit that's named after
1314 * the swap device in the kernel */
1315
1316 if (streq_ptr(s->what, s->devnode))
1317 return NULL;
1318
1319 LIST_FOREACH(same_devnode, other, s->same_devnode_next)
1320 if (streq_ptr(other->what, other->devnode))
1321 return UNIT(other);
1322
1323 LIST_FOREACH_BACKWARDS(same_devnode, other, s->same_devnode_prev) {
1324 if (streq_ptr(other->what, other->devnode))
1325 return UNIT(other);
1326
1327 first = other;
1328 }
1329
1330 /* Fall back to the first on the list */
1331 return UNIT(first);
1332 }
1333
swap_following_set(Unit * u,Set ** _set)1334 static int swap_following_set(Unit *u, Set **_set) {
1335 Swap *s = SWAP(u);
1336 _cleanup_set_free_ Set *set = NULL;
1337 int r;
1338
1339 assert(s);
1340 assert(_set);
1341
1342 if (LIST_JUST_US(same_devnode, s)) {
1343 *_set = NULL;
1344 return 0;
1345 }
1346
1347 set = set_new(NULL);
1348 if (!set)
1349 return -ENOMEM;
1350
1351 LIST_FOREACH_OTHERS(same_devnode, other, s) {
1352 r = set_put(set, other);
1353 if (r < 0)
1354 return r;
1355 }
1356
1357 *_set = TAKE_PTR(set);
1358 return 1;
1359 }
1360
swap_shutdown(Manager * m)1361 static void swap_shutdown(Manager *m) {
1362 assert(m);
1363
1364 m->swap_event_source = sd_event_source_disable_unref(m->swap_event_source);
1365 m->proc_swaps = safe_fclose(m->proc_swaps);
1366 m->swaps_by_devnode = hashmap_free(m->swaps_by_devnode);
1367 }
1368
swap_enumerate(Manager * m)1369 static void swap_enumerate(Manager *m) {
1370 int r;
1371
1372 assert(m);
1373
1374 if (!m->proc_swaps) {
1375 m->proc_swaps = fopen("/proc/swaps", "re");
1376 if (!m->proc_swaps) {
1377 if (errno == ENOENT)
1378 log_debug_errno(errno, "Not swap enabled, skipping enumeration.");
1379 else
1380 log_warning_errno(errno, "Failed to open /proc/swaps, ignoring: %m");
1381
1382 return;
1383 }
1384
1385 r = sd_event_add_io(m->event, &m->swap_event_source, fileno(m->proc_swaps), EPOLLPRI, swap_dispatch_io, m);
1386 if (r < 0) {
1387 log_error_errno(r, "Failed to watch /proc/swaps: %m");
1388 goto fail;
1389 }
1390
1391 /* Dispatch this before we dispatch SIGCHLD, so that
1392 * we always get the events from /proc/swaps before
1393 * the SIGCHLD of /sbin/swapon. */
1394 r = sd_event_source_set_priority(m->swap_event_source, SD_EVENT_PRIORITY_NORMAL-10);
1395 if (r < 0) {
1396 log_error_errno(r, "Failed to change /proc/swaps priority: %m");
1397 goto fail;
1398 }
1399
1400 (void) sd_event_source_set_description(m->swap_event_source, "swap-proc");
1401 }
1402
1403 r = swap_load_proc_swaps(m, false);
1404 if (r < 0)
1405 goto fail;
1406
1407 return;
1408
1409 fail:
1410 swap_shutdown(m);
1411 }
1412
swap_process_device_new(Manager * m,sd_device * dev)1413 int swap_process_device_new(Manager *m, sd_device *dev) {
1414 _cleanup_free_ char *e = NULL;
1415 const char *dn, *devlink;
1416 Unit *u;
1417 int r;
1418
1419 assert(m);
1420 assert(dev);
1421
1422 if (sd_device_get_devname(dev, &dn) < 0)
1423 return 0;
1424
1425 r = unit_name_from_path(dn, ".swap", &e);
1426 if (r < 0) {
1427 log_debug_errno(r, "Cannot convert device name '%s' to unit name, ignoring: %m", dn);
1428 return 0;
1429 }
1430
1431 u = manager_get_unit(m, e);
1432 if (u)
1433 r = swap_set_devnode(SWAP(u), dn);
1434
1435 FOREACH_DEVICE_DEVLINK(dev, devlink) {
1436 _cleanup_free_ char *n = NULL;
1437 int q;
1438
1439 q = unit_name_from_path(devlink, ".swap", &n);
1440 if (IN_SET(q, -EINVAL, -ENAMETOOLONG)) /* If name too long or otherwise not convertible to
1441 * unit name, we can't manage it */
1442 continue;
1443 if (q < 0)
1444 return q;
1445
1446 u = manager_get_unit(m, n);
1447 if (u) {
1448 q = swap_set_devnode(SWAP(u), dn);
1449 if (q < 0)
1450 r = q;
1451 }
1452 }
1453
1454 return r;
1455 }
1456
swap_process_device_remove(Manager * m,sd_device * dev)1457 int swap_process_device_remove(Manager *m, sd_device *dev) {
1458 const char *dn;
1459 int r;
1460 Swap *s;
1461
1462 r = sd_device_get_devname(dev, &dn);
1463 if (r < 0)
1464 return 0;
1465
1466 while ((s = hashmap_get(m->swaps_by_devnode, dn))) {
1467 int q;
1468
1469 q = swap_set_devnode(s, NULL);
1470 if (q < 0)
1471 r = q;
1472 }
1473
1474 return r;
1475 }
1476
swap_reset_failed(Unit * u)1477 static void swap_reset_failed(Unit *u) {
1478 Swap *s = SWAP(u);
1479
1480 assert(s);
1481
1482 if (s->state == SWAP_FAILED)
1483 swap_set_state(s, SWAP_DEAD);
1484
1485 s->result = SWAP_SUCCESS;
1486 s->clean_result = SWAP_SUCCESS;
1487 }
1488
swap_kill(Unit * u,KillWho who,int signo,sd_bus_error * error)1489 static int swap_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
1490 return unit_kill_common(u, who, signo, -1, SWAP(u)->control_pid, error);
1491 }
1492
swap_get_timeout(Unit * u,usec_t * timeout)1493 static int swap_get_timeout(Unit *u, usec_t *timeout) {
1494 Swap *s = SWAP(u);
1495 usec_t t;
1496 int r;
1497
1498 assert(s);
1499 assert(u);
1500
1501 if (!s->timer_event_source)
1502 return 0;
1503
1504 r = sd_event_source_get_time(s->timer_event_source, &t);
1505 if (r < 0)
1506 return r;
1507 if (t == USEC_INFINITY)
1508 return 0;
1509
1510 *timeout = t;
1511 return 1;
1512 }
1513
swap_supported(void)1514 static bool swap_supported(void) {
1515 static int supported = -1;
1516
1517 /* If swap support is not available in the kernel, or we are
1518 * running in a container we don't support swap units, and any
1519 * attempts to starting one should fail immediately. */
1520
1521 if (supported < 0)
1522 supported =
1523 access("/proc/swaps", F_OK) >= 0 &&
1524 detect_container() <= 0;
1525
1526 return supported;
1527 }
1528
swap_control_pid(Unit * u)1529 static int swap_control_pid(Unit *u) {
1530 Swap *s = SWAP(u);
1531
1532 assert(s);
1533
1534 return s->control_pid;
1535 }
1536
swap_clean(Unit * u,ExecCleanMask mask)1537 static int swap_clean(Unit *u, ExecCleanMask mask) {
1538 _cleanup_strv_free_ char **l = NULL;
1539 Swap *s = SWAP(u);
1540 int r;
1541
1542 assert(s);
1543 assert(mask != 0);
1544
1545 if (s->state != SWAP_DEAD)
1546 return -EBUSY;
1547
1548 r = exec_context_get_clean_directories(&s->exec_context, u->manager->prefix, mask, &l);
1549 if (r < 0)
1550 return r;
1551
1552 if (strv_isempty(l))
1553 return -EUNATCH;
1554
1555 swap_unwatch_control_pid(s);
1556 s->clean_result = SWAP_SUCCESS;
1557 s->control_command = NULL;
1558 s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
1559
1560 r = swap_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->exec_context.timeout_clean_usec));
1561 if (r < 0)
1562 goto fail;
1563
1564 r = unit_fork_and_watch_rm_rf(u, l, &s->control_pid);
1565 if (r < 0)
1566 goto fail;
1567
1568 swap_set_state(s, SWAP_CLEANING);
1569
1570 return 0;
1571
1572 fail:
1573 log_unit_warning_errno(u, r, "Failed to initiate cleaning: %m");
1574 s->clean_result = SWAP_FAILURE_RESOURCES;
1575 s->timer_event_source = sd_event_source_disable_unref(s->timer_event_source);
1576 return r;
1577 }
1578
swap_can_clean(Unit * u,ExecCleanMask * ret)1579 static int swap_can_clean(Unit *u, ExecCleanMask *ret) {
1580 Swap *s = SWAP(u);
1581
1582 assert(s);
1583
1584 return exec_context_get_clean_mask(&s->exec_context, ret);
1585 }
1586
swap_can_start(Unit * u)1587 static int swap_can_start(Unit *u) {
1588 Swap *s = SWAP(u);
1589 int r;
1590
1591 assert(s);
1592
1593 r = unit_test_start_limit(u);
1594 if (r < 0) {
1595 swap_enter_dead(s, SWAP_FAILURE_START_LIMIT_HIT);
1596 return r;
1597 }
1598
1599 return 1;
1600 }
1601
1602 static const char* const swap_exec_command_table[_SWAP_EXEC_COMMAND_MAX] = {
1603 [SWAP_EXEC_ACTIVATE] = "ExecActivate",
1604 [SWAP_EXEC_DEACTIVATE] = "ExecDeactivate",
1605 };
1606
1607 DEFINE_STRING_TABLE_LOOKUP(swap_exec_command, SwapExecCommand);
1608
1609 static const char* const swap_result_table[_SWAP_RESULT_MAX] = {
1610 [SWAP_SUCCESS] = "success",
1611 [SWAP_FAILURE_RESOURCES] = "resources",
1612 [SWAP_FAILURE_TIMEOUT] = "timeout",
1613 [SWAP_FAILURE_EXIT_CODE] = "exit-code",
1614 [SWAP_FAILURE_SIGNAL] = "signal",
1615 [SWAP_FAILURE_CORE_DUMP] = "core-dump",
1616 [SWAP_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
1617 };
1618
1619 DEFINE_STRING_TABLE_LOOKUP(swap_result, SwapResult);
1620
1621 const UnitVTable swap_vtable = {
1622 .object_size = sizeof(Swap),
1623 .exec_context_offset = offsetof(Swap, exec_context),
1624 .cgroup_context_offset = offsetof(Swap, cgroup_context),
1625 .kill_context_offset = offsetof(Swap, kill_context),
1626 .exec_runtime_offset = offsetof(Swap, exec_runtime),
1627 .dynamic_creds_offset = offsetof(Swap, dynamic_creds),
1628
1629 .sections =
1630 "Unit\0"
1631 "Swap\0"
1632 "Install\0",
1633 .private_section = "Swap",
1634
1635 .can_fail = true,
1636
1637 .init = swap_init,
1638 .load = swap_load,
1639 .done = swap_done,
1640
1641 .coldplug = swap_coldplug,
1642
1643 .dump = swap_dump,
1644
1645 .start = swap_start,
1646 .stop = swap_stop,
1647
1648 .kill = swap_kill,
1649 .clean = swap_clean,
1650 .can_clean = swap_can_clean,
1651
1652 .get_timeout = swap_get_timeout,
1653
1654 .serialize = swap_serialize,
1655 .deserialize_item = swap_deserialize_item,
1656
1657 .active_state = swap_active_state,
1658 .sub_state_to_string = swap_sub_state_to_string,
1659
1660 .will_restart = unit_will_restart_default,
1661
1662 .may_gc = swap_may_gc,
1663 .is_extrinsic = swap_is_extrinsic,
1664
1665 .sigchld_event = swap_sigchld_event,
1666
1667 .reset_failed = swap_reset_failed,
1668
1669 .control_pid = swap_control_pid,
1670
1671 .bus_set_property = bus_swap_set_property,
1672 .bus_commit_properties = bus_swap_commit_properties,
1673
1674 .following = swap_following,
1675 .following_set = swap_following_set,
1676
1677 .enumerate = swap_enumerate,
1678 .shutdown = swap_shutdown,
1679 .supported = swap_supported,
1680
1681 .status_message_formats = {
1682 .starting_stopping = {
1683 [0] = "Activating swap %s...",
1684 [1] = "Deactivating swap %s...",
1685 },
1686 .finished_start_job = {
1687 [JOB_DONE] = "Activated swap %s.",
1688 [JOB_FAILED] = "Failed to activate swap %s.",
1689 [JOB_TIMEOUT] = "Timed out activating swap %s.",
1690 },
1691 .finished_stop_job = {
1692 [JOB_DONE] = "Deactivated swap %s.",
1693 [JOB_FAILED] = "Failed deactivating swap %s.",
1694 [JOB_TIMEOUT] = "Timed out deactivating swap %s.",
1695 },
1696 },
1697
1698 .can_start = swap_can_start,
1699 };
1700