1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
23 #include <sys/epoll.h>
28 #include "unit-name.h"
29 #include "dbus-device.h"
31 #include "path-util.h"
32 #include "udev-util.h"
37 static const UnitActiveState state_translation_table[_DEVICE_STATE_MAX] = {
38 [DEVICE_DEAD] = UNIT_INACTIVE,
39 [DEVICE_PLUGGED] = UNIT_ACTIVE
42 static int device_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata);
44 static void device_unset_sysfs(Device *d) {
53 /* Remove this unit from the chain of devices which share the
55 devices = UNIT(d)->manager->devices_by_sysfs;
56 first = hashmap_get(devices, d->sysfs);
57 LIST_REMOVE(same_sysfs, first, d);
60 hashmap_remove_and_replace(devices, d->sysfs, first->sysfs, first);
62 hashmap_remove(devices, d->sysfs);
68 static void device_init(Unit *u) {
69 Device *d = DEVICE(u);
72 assert(UNIT(d)->load_state == UNIT_STUB);
74 /* In contrast to all other unit types we timeout jobs waiting
75 * for devices by default. This is because they otherwise wait
76 * indefinitely for plugged in devices, something which cannot
77 * happen for the other units since their operations time out
79 u->job_timeout = u->manager->default_timeout_start_usec;
81 u->ignore_on_isolate = true;
82 u->ignore_on_snapshot = true;
85 static void device_done(Unit *u) {
86 Device *d = DEVICE(u);
90 device_unset_sysfs(d);
93 static void device_set_state(Device *d, DeviceState state) {
94 DeviceState old_state;
100 if (state != old_state)
101 log_debug_unit(UNIT(d)->id,
102 "%s changed %s -> %s", UNIT(d)->id,
103 device_state_to_string(old_state),
104 device_state_to_string(state));
106 unit_notify(UNIT(d), state_translation_table[old_state], state_translation_table[state], true);
109 static int device_coldplug(Unit *u) {
110 Device *d = DEVICE(u);
113 assert(d->state == DEVICE_DEAD);
116 device_set_state(d, DEVICE_PLUGGED);
121 static void device_dump(Unit *u, FILE *f, const char *prefix) {
122 Device *d = DEVICE(u);
127 "%sDevice State: %s\n"
128 "%sSysfs Path: %s\n",
129 prefix, device_state_to_string(d->state),
130 prefix, strna(d->sysfs));
133 _pure_ static UnitActiveState device_active_state(Unit *u) {
136 return state_translation_table[DEVICE(u)->state];
139 _pure_ static const char *device_sub_state_to_string(Unit *u) {
142 return device_state_to_string(DEVICE(u)->state);
145 static int device_add_escaped_name(Unit *u, const char *dn) {
146 _cleanup_free_ char *e = NULL;
151 assert(dn[0] == '/');
153 e = unit_name_from_path(dn, ".device");
157 r = unit_add_name(u, e);
158 if (r < 0 && r != -EEXIST)
164 static int device_find_escape_name(Manager *m, const char *dn, Unit **_u) {
165 _cleanup_free_ char *e = NULL;
170 assert(dn[0] == '/');
173 e = unit_name_from_path(dn, ".device");
177 u = manager_get_unit(m, e);
186 static int device_update_unit(Manager *m, struct udev_device *dev, const char *path, bool main) {
187 const char *sysfs, *model;
194 sysfs = udev_device_get_syspath(dev);
198 r = device_find_escape_name(m, path, &u);
202 if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs))
208 u = unit_new(m, sizeof(Device));
212 r = device_add_escaped_name(u, path);
216 unit_add_to_load_queue(u);
220 /* If this was created via some dependency and has not
221 * actually been seen yet ->sysfs will not be
222 * initialized. Hence initialize it if necessary. */
224 if (!DEVICE(u)->sysfs) {
227 DEVICE(u)->sysfs = strdup(sysfs);
228 if (!DEVICE(u)->sysfs) {
233 r = hashmap_ensure_allocated(&m->devices_by_sysfs, string_hash_func, string_compare_func);
237 first = hashmap_get(m->devices_by_sysfs, sysfs);
238 LIST_PREPEND(same_sysfs, first, DEVICE(u));
240 r = hashmap_replace(m->devices_by_sysfs, DEVICE(u)->sysfs, first);
245 if ((model = udev_device_get_property_value(dev, "ID_MODEL_FROM_DATABASE")) ||
246 (model = udev_device_get_property_value(dev, "ID_MODEL")))
247 r = unit_set_description(u, model);
249 r = unit_set_description(u, path);
256 /* The additional systemd udev properties we only
257 * interpret for the main object */
259 wants = udev_device_get_property_value(dev, m->running_as == SYSTEMD_USER ? "SYSTEMD_USER_WANTS" : "SYSTEMD_WANTS");
264 FOREACH_WORD_QUOTED(w, l, wants, state) {
265 _cleanup_free_ char *n = NULL;
271 n = unit_name_mangle(e);
277 r = unit_add_dependency_by_name(u, UNIT_WANTS, n, NULL, true);
284 /* Note that this won't dispatch the load queue, the caller
285 * has to do that if needed and appropriate */
287 unit_add_to_dbus_queue(u);
291 log_warning("Failed to load device unit: %s", strerror(-r));
299 static int device_process_new_device(Manager *m, struct udev_device *dev) {
300 const char *sysfs, *dn, *alias;
301 struct udev_list_entry *item = NULL, *first = NULL;
306 /* Don't pick up devices before udev finished initialization for them */
307 if (!udev_device_get_is_initialized(dev))
310 sysfs = udev_device_get_syspath(dev);
314 /* Add the main unit named after the sysfs path */
315 r = device_update_unit(m, dev, sysfs, true);
319 /* Add an additional unit for the device node */
320 dn = udev_device_get_devnode(dev);
322 device_update_unit(m, dev, dn, false);
324 /* Add additional units for all symlinks */
325 first = udev_device_get_devlinks_list_entry(dev);
326 udev_list_entry_foreach(item, first) {
330 /* Don't bother with the /dev/block links */
331 p = udev_list_entry_get_name(item);
333 if (path_startswith(p, "/dev/block/") ||
334 path_startswith(p, "/dev/char/"))
337 /* Verify that the symlink in the FS actually belongs
338 * to this device. This is useful to deal with
339 * conflicting devices, e.g. when two disks want the
340 * same /dev/disk/by-label/xxx link because they have
341 * the same label. We want to make sure that the same
342 * device that won the symlink wins in systemd, so we
343 * check the device node major/minor*/
344 if (stat(p, &st) >= 0)
345 if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) ||
346 st.st_rdev != udev_device_get_devnum(dev))
349 device_update_unit(m, dev, p, false);
352 /* Add additional units for all explicitly configured
354 alias = udev_device_get_property_value(dev, "SYSTEMD_ALIAS");
359 FOREACH_WORD_QUOTED(w, l, alias, state) {
365 if (path_is_absolute(e))
366 device_update_unit(m, dev, e, false);
368 log_warning("SYSTEMD_ALIAS for %s is not an absolute path, ignoring: %s", sysfs, e);
375 static void device_set_path_plugged(Manager *m, struct udev_device *dev) {
382 sysfs = udev_device_get_syspath(dev);
386 l = hashmap_get(m->devices_by_sysfs, sysfs);
387 LIST_FOREACH(same_sysfs, d, l)
388 device_set_state(d, DEVICE_PLUGGED);
391 static int device_process_removed_device(Manager *m, struct udev_device *dev) {
398 sysfs = udev_device_get_syspath(dev);
402 /* Remove all units of this sysfs path */
403 while ((d = hashmap_get(m->devices_by_sysfs, sysfs))) {
404 device_unset_sysfs(d);
405 device_set_state(d, DEVICE_DEAD);
411 static bool device_is_ready(struct udev_device *dev) {
416 ready = udev_device_get_property_value(dev, "SYSTEMD_READY");
420 return parse_boolean(ready) != 0;
423 static int device_process_new_path(Manager *m, const char *path) {
424 _cleanup_udev_device_unref_ struct udev_device *dev = NULL;
429 dev = udev_device_new_from_syspath(m->udev, path);
433 if (!device_is_ready(dev))
436 return device_process_new_device(m, dev);
439 static Unit *device_following(Unit *u) {
440 Device *d = DEVICE(u);
441 Device *other, *first = NULL;
445 if (startswith(u->id, "sys-"))
448 /* Make everybody follow the unit that's named after the sysfs path */
449 for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
450 if (startswith(UNIT(other)->id, "sys-"))
453 for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev) {
454 if (startswith(UNIT(other)->id, "sys-"))
463 static int device_following_set(Unit *u, Set **_set) {
464 Device *d = DEVICE(u), *other;
471 if (LIST_JUST_US(same_sysfs, d)) {
476 set = set_new(NULL, NULL);
480 LIST_FOREACH_AFTER(same_sysfs, other, d) {
481 r = set_put(set, other);
486 LIST_FOREACH_BEFORE(same_sysfs, other, d) {
487 r = set_put(set, other);
500 static void device_shutdown(Manager *m) {
503 m->udev_event_source = sd_event_source_unref(m->udev_event_source);
505 if (m->udev_monitor) {
506 udev_monitor_unref(m->udev_monitor);
507 m->udev_monitor = NULL;
510 hashmap_free(m->devices_by_sysfs);
511 m->devices_by_sysfs = NULL;
514 static int device_enumerate(Manager *m) {
515 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
516 struct udev_list_entry *item = NULL, *first = NULL;
521 if (!m->udev_monitor) {
522 m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev");
523 if (!m->udev_monitor) {
528 /* This will fail if we are unprivileged, but that
529 * should not matter much, as user instances won't run
531 udev_monitor_set_receive_buffer_size(m->udev_monitor, 128*1024*1024);
533 r = udev_monitor_filter_add_match_tag(m->udev_monitor, "systemd");
537 r = udev_monitor_enable_receiving(m->udev_monitor);
541 r = sd_event_add_io(m->event, udev_monitor_get_fd(m->udev_monitor), EPOLLIN, device_dispatch_io, m, &m->udev_event_source);
546 e = udev_enumerate_new(m->udev);
552 r = udev_enumerate_add_match_tag(e, "systemd");
556 r = udev_enumerate_scan_devices(e);
560 first = udev_enumerate_get_list_entry(e);
561 udev_list_entry_foreach(item, first)
562 device_process_new_path(m, udev_list_entry_get_name(item));
571 static int device_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
572 _cleanup_udev_device_unref_ struct udev_device *dev = NULL;
573 Manager *m = userdata;
579 if (revents != EPOLLIN) {
580 static RATELIMIT_DEFINE(limit, 10*USEC_PER_SEC, 5);
582 if (!ratelimit_test(&limit))
583 log_error("Failed to get udev event: %m");
584 if (!(revents & EPOLLIN))
589 * libudev might filter-out devices which pass the bloom
590 * filter, so getting NULL here is not necessarily an error.
592 dev = udev_monitor_receive_device(m->udev_monitor);
596 action = udev_device_get_action(dev);
598 log_error("Failed to get udev action string.");
602 if (streq(action, "remove") || !device_is_ready(dev)) {
603 r = device_process_removed_device(m, dev);
605 log_error("Failed to process device remove event: %s", strerror(-r));
607 r = swap_process_removed_device(m, dev);
609 log_error("Failed to process swap device remove event: %s", strerror(-r));
612 r = device_process_new_device(m, dev);
614 log_error("Failed to process device new event: %s", strerror(-r));
616 r = swap_process_new_device(m, dev);
618 log_error("Failed to process swap device new event: %s", strerror(-r));
620 manager_dispatch_load_queue(m);
622 device_set_path_plugged(m, dev);
628 static const char* const device_state_table[_DEVICE_STATE_MAX] = {
629 [DEVICE_DEAD] = "dead",
630 [DEVICE_PLUGGED] = "plugged"
633 DEFINE_STRING_TABLE_LOOKUP(device_state, DeviceState);
635 const UnitVTable device_vtable = {
636 .object_size = sizeof(Device),
642 .no_instances = true,
646 .load = unit_load_fragment_and_dropin_optional,
648 .coldplug = device_coldplug,
652 .active_state = device_active_state,
653 .sub_state_to_string = device_sub_state_to_string,
655 .bus_interface = "org.freedesktop.systemd1.Device",
656 .bus_changing_properties = bus_device_changing_properties,
657 .bus_vtable = bus_device_vtable,
659 .following = device_following,
660 .following_set = device_following_set,
662 .enumerate = device_enumerate,
663 .shutdown = device_shutdown,
665 .status_message_formats = {
666 .starting_stopping = {
667 [0] = "Expecting device %s...",
669 .finished_start_job = {
670 [JOB_DONE] = "Found device %s.",
671 [JOB_TIMEOUT] = "Timed out waiting for device %s.",