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_unit(UNIT(d)->id,
96 "%s changed %s -> %s", UNIT(d)->id,
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);
272 device_update_unit(m, dev, e, false);
278 wants = udev_device_get_property_value(dev, "SYSTEMD_WANTS");
283 FOREACH_WORD_QUOTED(w, l, wants, state) {
292 r = unit_add_dependency_by_name(u, UNIT_WANTS, e, NULL, true);
300 unit_add_to_dbus_queue(u);
304 log_warning("Failed to load device unit: %s", strerror(-r));
312 static int device_process_new_device(Manager *m, struct udev_device *dev, bool update_state) {
313 const char *sysfs, *dn;
314 struct udev_list_entry *item = NULL, *first = NULL;
318 if (!(sysfs = udev_device_get_syspath(dev)))
321 /* Add the main unit named after the sysfs path */
322 device_update_unit(m, dev, sysfs, true);
324 /* Add an additional unit for the device node */
325 if ((dn = udev_device_get_devnode(dev)))
326 device_update_unit(m, dev, dn, false);
328 /* Add additional units for all symlinks */
329 first = udev_device_get_devlinks_list_entry(dev);
330 udev_list_entry_foreach(item, first) {
334 /* Don't bother with the /dev/block links */
335 p = udev_list_entry_get_name(item);
337 if (path_startswith(p, "/dev/block/") ||
338 path_startswith(p, "/dev/char/"))
341 /* Verify that the symlink in the FS actually belongs
342 * to this device. This is useful to deal with
343 * conflicting devices, e.g. when two disks want the
344 * same /dev/disk/by-label/xxx link because they have
345 * the same label. We want to make sure that the same
346 * device that won the symlink wins in systemd, so we
347 * check the device node major/minor*/
348 if (stat(p, &st) >= 0)
349 if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) ||
350 st.st_rdev != udev_device_get_devnum(dev))
353 device_update_unit(m, dev, p, false);
359 manager_dispatch_load_queue(m);
361 l = hashmap_get(m->devices_by_sysfs, sysfs);
362 LIST_FOREACH(same_sysfs, d, l)
363 device_set_state(d, DEVICE_PLUGGED);
369 static int device_process_path(Manager *m, const char *path, bool update_state) {
371 struct udev_device *dev;
376 if (!(dev = udev_device_new_from_syspath(m->udev, path))) {
377 log_warning("Failed to get udev device object from udev for path %s.", path);
381 r = device_process_new_device(m, dev, update_state);
382 udev_device_unref(dev);
386 static int device_process_removed_device(Manager *m, struct udev_device *dev) {
393 if (!(sysfs = udev_device_get_syspath(dev)))
396 /* Remove all units of this sysfs path */
397 while ((d = hashmap_get(m->devices_by_sysfs, sysfs))) {
398 device_unset_sysfs(d);
399 device_set_state(d, DEVICE_DEAD);
405 static Unit *device_following(Unit *u) {
406 Device *d = DEVICE(u);
407 Device *other, *first = NULL;
411 if (startswith(u->id, "sys-"))
414 /* Make everybody follow the unit that's named after the sysfs path */
415 for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
416 if (startswith(UNIT(other)->id, "sys-"))
419 for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev) {
420 if (startswith(UNIT(other)->id, "sys-"))
429 static int device_following_set(Unit *u, Set **_s) {
430 Device *d = DEVICE(u);
438 if (!d->same_sysfs_prev && !d->same_sysfs_next) {
443 if (!(s = set_new(NULL, NULL)))
446 for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
447 if ((r = set_put(s, other)) < 0)
450 for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev)
451 if ((r = set_put(s, other)) < 0)
462 static void device_shutdown(Manager *m) {
465 if (m->udev_monitor) {
466 udev_monitor_unref(m->udev_monitor);
467 m->udev_monitor = NULL;
475 hashmap_free(m->devices_by_sysfs);
476 m->devices_by_sysfs = NULL;
479 static int device_enumerate(Manager *m) {
480 struct epoll_event ev;
482 struct udev_enumerate *e = NULL;
483 struct udev_list_entry *item = NULL, *first = NULL;
488 if (!(m->udev = udev_new()))
491 if (!(m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev"))) {
496 /* This will fail if we are unprivileged, but that
497 * should not matter much, as user instances won't run
499 udev_monitor_set_receive_buffer_size(m->udev_monitor, 128*1024*1024);
501 if (udev_monitor_filter_add_match_tag(m->udev_monitor, "systemd") < 0) {
506 if (udev_monitor_enable_receiving(m->udev_monitor) < 0) {
511 m->udev_watch.type = WATCH_UDEV;
512 m->udev_watch.fd = udev_monitor_get_fd(m->udev_monitor);
516 ev.data.ptr = &m->udev_watch;
518 if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->udev_watch.fd, &ev) < 0)
522 if (!(e = udev_enumerate_new(m->udev))) {
526 if (udev_enumerate_add_match_tag(e, "systemd") < 0) {
531 if (udev_enumerate_scan_devices(e) < 0) {
536 first = udev_enumerate_get_list_entry(e);
537 udev_list_entry_foreach(item, first)
538 device_process_path(m, udev_list_entry_get_name(item), false);
540 udev_enumerate_unref(e);
545 udev_enumerate_unref(e);
551 void device_fd_event(Manager *m, int events) {
552 struct udev_device *dev;
554 const char *action, *ready;
558 if (events != EPOLLIN) {
559 static RATELIMIT_DEFINE(limit, 10*USEC_PER_SEC, 5);
561 if (!ratelimit_test(&limit))
562 log_error("Failed to get udev event: %m");
563 if (!(events & EPOLLIN))
567 if (!(dev = udev_monitor_receive_device(m->udev_monitor))) {
569 * libudev might filter-out devices which pass the bloom filter,
570 * so getting NULL here is not necessarily an error
575 if (!(action = udev_device_get_action(dev))) {
576 log_error("Failed to get udev action string.");
580 ready = udev_device_get_property_value(dev, "SYSTEMD_READY");
582 if (streq(action, "remove") || (ready && parse_boolean(ready) == 0)) {
583 if ((r = device_process_removed_device(m, dev)) < 0) {
584 log_error("Failed to process udev device event: %s", strerror(-r));
588 if ((r = device_process_new_device(m, dev, true)) < 0) {
589 log_error("Failed to process udev device event: %s", strerror(-r));
595 udev_device_unref(dev);
598 static const char* const device_state_table[_DEVICE_STATE_MAX] = {
599 [DEVICE_DEAD] = "dead",
600 [DEVICE_PLUGGED] = "plugged"
603 DEFINE_STRING_TABLE_LOOKUP(device_state, DeviceState);
605 const UnitVTable device_vtable = {
606 .object_size = sizeof(Device),
612 .no_instances = true,
616 .load = unit_load_fragment_and_dropin_optional,
618 .coldplug = device_coldplug,
622 .active_state = device_active_state,
623 .sub_state_to_string = device_sub_state_to_string,
625 .bus_interface = "org.freedesktop.systemd1.Device",
626 .bus_message_handler = bus_device_message_handler,
627 .bus_invalidating_properties = bus_device_invalidating_properties,
629 .following = device_following,
630 .following_set = device_following_set,
632 .enumerate = device_enumerate,
633 .shutdown = device_shutdown,
635 .status_message_formats = {
636 .starting_stopping = {
637 [0] = "Expecting device %s...",
639 .finished_start_job = {
640 [JOB_DONE] = "Found device %s.",
641 [JOB_TIMEOUT] = "Timed out waiting for device %s.",