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>
30 #include "unit-name.h"
31 #include "dbus-device.h"
33 #include "path-util.h"
35 static const UnitActiveState state_translation_table[_DEVICE_STATE_MAX] = {
36 [DEVICE_DEAD] = UNIT_INACTIVE,
37 [DEVICE_PLUGGED] = UNIT_ACTIVE
40 static void device_unset_sysfs(Device *d) {
48 /* Remove this unit from the chain of devices which share the
50 first = hashmap_get(UNIT(d)->manager->devices_by_sysfs, d->sysfs);
51 LIST_REMOVE(Device, same_sysfs, first, d);
54 hashmap_remove_and_replace(UNIT(d)->manager->devices_by_sysfs, d->sysfs, first->sysfs, first);
56 hashmap_remove(UNIT(d)->manager->devices_by_sysfs, d->sysfs);
62 static void device_init(Unit *u) {
63 Device *d = DEVICE(u);
66 assert(UNIT(d)->load_state == UNIT_STUB);
68 /* In contrast to all other unit types we timeout jobs waiting
69 * for devices by default. This is because they otherwise wait
70 * indefinitely for plugged in devices, something which cannot
71 * happen for the other units since their operations time out
73 UNIT(d)->job_timeout = DEFAULT_TIMEOUT_USEC;
75 UNIT(d)->ignore_on_isolate = true;
76 UNIT(d)->ignore_on_snapshot = true;
79 static void device_done(Unit *u) {
80 Device *d = DEVICE(u);
84 device_unset_sysfs(d);
87 static void device_set_state(Device *d, DeviceState state) {
88 DeviceState old_state;
94 if (state != old_state)
95 log_debug("%s changed %s -> %s",
97 device_state_to_string(old_state),
98 device_state_to_string(state));
100 unit_notify(UNIT(d), state_translation_table[old_state], state_translation_table[state], true);
103 static int device_coldplug(Unit *u) {
104 Device *d = DEVICE(u);
107 assert(d->state == DEVICE_DEAD);
110 device_set_state(d, DEVICE_PLUGGED);
115 static void device_dump(Unit *u, FILE *f, const char *prefix) {
116 Device *d = DEVICE(u);
121 "%sDevice State: %s\n"
122 "%sSysfs Path: %s\n",
123 prefix, device_state_to_string(d->state),
124 prefix, strna(d->sysfs));
127 static UnitActiveState device_active_state(Unit *u) {
130 return state_translation_table[DEVICE(u)->state];
133 static const char *device_sub_state_to_string(Unit *u) {
136 return device_state_to_string(DEVICE(u)->state);
139 static int device_add_escaped_name(Unit *u, const char *dn) {
145 assert(dn[0] == '/');
147 e = unit_name_from_path(dn, ".device");
151 r = unit_add_name(u, e);
154 if (r < 0 && r != -EEXIST)
160 static int device_find_escape_name(Manager *m, const char *dn, Unit **_u) {
166 assert(dn[0] == '/');
169 e = unit_name_from_path(dn, ".device");
173 u = manager_get_unit(m, e);
184 static int device_update_unit(Manager *m, struct udev_device *dev, const char *path, bool main) {
185 const char *sysfs, *model;
192 if (!(sysfs = udev_device_get_syspath(dev)))
195 if ((r = device_find_escape_name(m, path, &u)) < 0)
198 if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs))
204 u = unit_new(m, sizeof(Device));
208 r = device_add_escaped_name(u, path);
212 unit_add_to_load_queue(u);
216 /* If this was created via some dependency and has not
217 * actually been seen yet ->sysfs will not be
218 * initialized. Hence initialize it if necessary. */
220 if (!DEVICE(u)->sysfs) {
223 if (!(DEVICE(u)->sysfs = strdup(sysfs))) {
228 if (!m->devices_by_sysfs)
229 if (!(m->devices_by_sysfs = hashmap_new(string_hash_func, string_compare_func))) {
234 first = hashmap_get(m->devices_by_sysfs, sysfs);
235 LIST_PREPEND(Device, same_sysfs, first, DEVICE(u));
237 if ((r = hashmap_replace(m->devices_by_sysfs, DEVICE(u)->sysfs, first)) < 0)
241 if ((model = udev_device_get_property_value(dev, "ID_MODEL_FROM_DATABASE")) ||
242 (model = udev_device_get_property_value(dev, "ID_MODEL"))) {
243 if ((r = unit_set_description(u, model)) < 0)
246 if ((r = unit_set_description(u, path)) < 0)
250 /* The additional systemd udev properties we only
251 * interpret for the main object */
252 const char *wants, *alias;
254 alias = udev_device_get_property_value(dev, "SYSTEMD_ALIAS");
259 FOREACH_WORD_QUOTED(w, l, alias, state) {
269 log_warning("SYSTEMD_ALIAS for %s is not a path, ignoring: %s", sysfs, e);
273 r = device_add_escaped_name(u, e);
281 wants = udev_device_get_property_value(dev, "SYSTEMD_WANTS");
286 FOREACH_WORD_QUOTED(w, l, wants, state) {
295 r = unit_add_dependency_by_name(u, UNIT_WANTS, e, NULL, true);
303 unit_add_to_dbus_queue(u);
307 log_warning("Failed to load device unit: %s", strerror(-r));
315 static int device_process_new_device(Manager *m, struct udev_device *dev, bool update_state) {
316 const char *sysfs, *dn;
317 struct udev_list_entry *item = NULL, *first = NULL;
321 if (!(sysfs = udev_device_get_syspath(dev)))
324 /* Add the main unit named after the sysfs path */
325 device_update_unit(m, dev, sysfs, true);
327 /* Add an additional unit for the device node */
328 if ((dn = udev_device_get_devnode(dev)))
329 device_update_unit(m, dev, dn, false);
331 /* Add additional units for all symlinks */
332 first = udev_device_get_devlinks_list_entry(dev);
333 udev_list_entry_foreach(item, first) {
337 /* Don't bother with the /dev/block links */
338 p = udev_list_entry_get_name(item);
340 if (path_startswith(p, "/dev/block/") ||
341 path_startswith(p, "/dev/char/"))
344 /* Verify that the symlink in the FS actually belongs
345 * to this device. This is useful to deal with
346 * conflicting devices, e.g. when two disks want the
347 * same /dev/disk/by-label/xxx link because they have
348 * the same label. We want to make sure that the same
349 * device that won the symlink wins in systemd, so we
350 * check the device node major/minor*/
351 if (stat(p, &st) >= 0)
352 if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) ||
353 st.st_rdev != udev_device_get_devnum(dev))
356 device_update_unit(m, dev, p, false);
362 manager_dispatch_load_queue(m);
364 l = hashmap_get(m->devices_by_sysfs, sysfs);
365 LIST_FOREACH(same_sysfs, d, l)
366 device_set_state(d, DEVICE_PLUGGED);
372 static int device_process_path(Manager *m, const char *path, bool update_state) {
374 struct udev_device *dev;
379 if (!(dev = udev_device_new_from_syspath(m->udev, path))) {
380 log_warning("Failed to get udev device object from udev for path %s.", path);
384 r = device_process_new_device(m, dev, update_state);
385 udev_device_unref(dev);
389 static int device_process_removed_device(Manager *m, struct udev_device *dev) {
396 if (!(sysfs = udev_device_get_syspath(dev)))
399 /* Remove all units of this sysfs path */
400 while ((d = hashmap_get(m->devices_by_sysfs, sysfs))) {
401 device_unset_sysfs(d);
402 device_set_state(d, DEVICE_DEAD);
408 static Unit *device_following(Unit *u) {
409 Device *d = DEVICE(u);
410 Device *other, *first = NULL;
414 if (startswith(u->id, "sys-"))
417 /* Make everybody follow the unit that's named after the sysfs path */
418 for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
419 if (startswith(UNIT(other)->id, "sys-"))
422 for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev) {
423 if (startswith(UNIT(other)->id, "sys-"))
432 static int device_following_set(Unit *u, Set **_s) {
433 Device *d = DEVICE(u);
441 if (!d->same_sysfs_prev && !d->same_sysfs_next) {
446 if (!(s = set_new(NULL, NULL)))
449 for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
450 if ((r = set_put(s, other)) < 0)
453 for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev)
454 if ((r = set_put(s, other)) < 0)
465 static void device_shutdown(Manager *m) {
468 if (m->udev_monitor) {
469 udev_monitor_unref(m->udev_monitor);
470 m->udev_monitor = NULL;
478 hashmap_free(m->devices_by_sysfs);
479 m->devices_by_sysfs = NULL;
482 static int device_enumerate(Manager *m) {
483 struct epoll_event ev;
485 struct udev_enumerate *e = NULL;
486 struct udev_list_entry *item = NULL, *first = NULL;
491 if (!(m->udev = udev_new()))
494 if (!(m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev"))) {
499 /* This will fail if we are unprivileged, but that
500 * should not matter much, as user instances won't run
502 udev_monitor_set_receive_buffer_size(m->udev_monitor, 128*1024*1024);
504 if (udev_monitor_filter_add_match_tag(m->udev_monitor, "systemd") < 0) {
509 if (udev_monitor_enable_receiving(m->udev_monitor) < 0) {
514 m->udev_watch.type = WATCH_UDEV;
515 m->udev_watch.fd = udev_monitor_get_fd(m->udev_monitor);
519 ev.data.ptr = &m->udev_watch;
521 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->udev_watch.fd, &ev) < 0)
525 if (!(e = udev_enumerate_new(m->udev))) {
529 if (udev_enumerate_add_match_tag(e, "systemd") < 0) {
534 if (udev_enumerate_scan_devices(e) < 0) {
539 first = udev_enumerate_get_list_entry(e);
540 udev_list_entry_foreach(item, first)
541 device_process_path(m, udev_list_entry_get_name(item), false);
543 udev_enumerate_unref(e);
548 udev_enumerate_unref(e);
554 void device_fd_event(Manager *m, int events) {
555 struct udev_device *dev;
557 const char *action, *ready;
561 if (events != EPOLLIN) {
562 static RATELIMIT_DEFINE(limit, 10*USEC_PER_SEC, 5);
564 if (!ratelimit_test(&limit))
565 log_error("Failed to get udev event: %m");
566 if (!(events & EPOLLIN))
570 if (!(dev = udev_monitor_receive_device(m->udev_monitor))) {
572 * libudev might filter-out devices which pass the bloom filter,
573 * so getting NULL here is not necessarily an error
578 if (!(action = udev_device_get_action(dev))) {
579 log_error("Failed to get udev action string.");
583 ready = udev_device_get_property_value(dev, "SYSTEMD_READY");
585 if (streq(action, "remove") || (ready && parse_boolean(ready) == 0)) {
586 if ((r = device_process_removed_device(m, dev)) < 0) {
587 log_error("Failed to process udev device event: %s", strerror(-r));
591 if ((r = device_process_new_device(m, dev, true)) < 0) {
592 log_error("Failed to process udev device event: %s", strerror(-r));
598 udev_device_unref(dev);
601 static const char* const device_state_table[_DEVICE_STATE_MAX] = {
602 [DEVICE_DEAD] = "dead",
603 [DEVICE_PLUGGED] = "plugged"
606 DEFINE_STRING_TABLE_LOOKUP(device_state, DeviceState);
608 const UnitVTable device_vtable = {
609 .object_size = sizeof(Device),
615 .no_instances = true,
619 .load = unit_load_fragment_and_dropin_optional,
621 .coldplug = device_coldplug,
625 .active_state = device_active_state,
626 .sub_state_to_string = device_sub_state_to_string,
628 .bus_interface = "org.freedesktop.systemd1.Device",
629 .bus_message_handler = bus_device_message_handler,
630 .bus_invalidating_properties = bus_device_invalidating_properties,
632 .following = device_following,
633 .following_set = device_following_set,
635 .enumerate = device_enumerate,
636 .shutdown = device_shutdown,
638 .status_message_formats = {
639 .starting_stopping = {
640 [0] = "Expecting device %s...",
642 .finished_start_job = {
643 [JOB_DONE] = "Found device %s.",
644 [JOB_TIMEOUT] = "Timed out waiting for device %s.",