2 * Copyright (C) 2004-2012 Kay Sievers <kay@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
4 * Copyright (C) 2009 Canonical Ltd.
5 * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
36 #include <sys/prctl.h>
37 #include <sys/socket.h>
39 #include <sys/signalfd.h>
40 #include <sys/epoll.h>
44 #include <sys/ioctl.h>
45 #include <sys/inotify.h>
46 #include <sys/utsname.h>
49 #include "sd-daemon.h"
50 #include "cgroup-util.h"
51 #include "dev-setup.h"
56 void udev_main_log(struct udev *udev, int priority,
57 const char *file, int line, const char *fn,
58 const char *format, va_list args)
60 log_metav(priority, file, line, fn, format, args);
63 static struct udev_rules *rules;
64 static struct udev_ctrl *udev_ctrl;
65 static struct udev_monitor *monitor;
66 static int worker_watch[2] = { -1, -1 };
67 static int fd_signal = -1;
68 static int fd_ep = -1;
69 static int fd_inotify = -1;
70 static bool stop_exec_queue;
73 static int children_max;
74 static int exec_delay;
75 static sigset_t sigmask_orig;
76 static UDEV_LIST(event_list);
77 static UDEV_LIST(worker_list);
78 static char *udev_cgroup;
79 static bool udev_exit;
88 struct udev_list_node node;
90 struct udev_device *dev;
91 enum event_state state;
93 unsigned long long int delaying_seqnum;
94 unsigned long long int seqnum;
97 const char *devpath_old;
106 static inline struct event *node_to_event(struct udev_list_node *node)
108 return container_of(node, struct event, node);
111 static void event_queue_cleanup(struct udev *udev, enum event_state type);
121 struct udev_list_node node;
125 struct udev_monitor *monitor;
126 enum worker_state state;
128 usec_t event_start_usec;
131 /* passed from worker to main process */
132 struct worker_message {
137 static inline struct worker *node_to_worker(struct udev_list_node *node)
139 return container_of(node, struct worker, node);
142 static void event_queue_delete(struct event *event)
144 udev_list_node_remove(&event->node);
145 udev_device_unref(event->dev);
149 static struct worker *worker_ref(struct worker *worker)
155 static void worker_cleanup(struct worker *worker)
157 udev_list_node_remove(&worker->node);
158 udev_monitor_unref(worker->monitor);
163 static void worker_unref(struct worker *worker)
166 if (worker->refcount > 0)
168 log_debug("worker [%u] cleaned up", worker->pid);
169 worker_cleanup(worker);
172 static void worker_list_cleanup(struct udev *udev)
174 struct udev_list_node *loop, *tmp;
176 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
177 struct worker *worker = node_to_worker(loop);
179 worker_cleanup(worker);
183 static void worker_new(struct event *event)
185 struct udev *udev = event->udev;
186 struct worker *worker;
187 struct udev_monitor *worker_monitor;
190 /* listen for new events */
191 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
192 if (worker_monitor == NULL)
194 /* allow the main daemon netlink address to send devices to the worker */
195 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
196 udev_monitor_enable_receiving(worker_monitor);
198 worker = new0(struct worker, 1);
199 if (worker == NULL) {
200 udev_monitor_unref(worker_monitor);
203 /* worker + event reference */
204 worker->refcount = 2;
210 struct udev_device *dev = NULL;
212 struct epoll_event ep_signal, ep_monitor;
214 int rc = EXIT_SUCCESS;
216 /* take initial device from queue */
221 worker_list_cleanup(udev);
222 event_queue_cleanup(udev, EVENT_UNDEF);
223 udev_monitor_unref(monitor);
224 udev_ctrl_unref(udev_ctrl);
227 close(worker_watch[READ_END]);
230 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
232 log_error("error creating signalfd %m");
237 fd_ep = epoll_create1(EPOLL_CLOEXEC);
239 log_error("error creating epoll fd: %m");
244 memzero(&ep_signal, sizeof(struct epoll_event));
245 ep_signal.events = EPOLLIN;
246 ep_signal.data.fd = fd_signal;
248 fd_monitor = udev_monitor_get_fd(worker_monitor);
249 memzero(&ep_monitor, sizeof(struct epoll_event));
250 ep_monitor.events = EPOLLIN;
251 ep_monitor.data.fd = fd_monitor;
253 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
254 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
255 log_error("fail to add fds to epoll: %m");
260 /* request TERM signal if parent exits */
261 prctl(PR_SET_PDEATHSIG, SIGTERM);
263 /* reset OOM score, we only protect the main daemon */
264 write_string_file("/proc/self/oom_score_adj", "0");
267 struct udev_event *udev_event;
268 struct worker_message msg;
272 log_debug("seq %llu running", udev_device_get_seqnum(dev));
273 udev_event = udev_event_new(dev);
274 if (udev_event == NULL) {
279 /* needed for SIGCHLD/SIGTERM in spawn() */
280 udev_event->fd_signal = fd_signal;
283 udev_event->exec_delay = exec_delay;
286 * Take a "read lock" on the device node; this establishes
287 * a concept of device "ownership" to serialize device
288 * access. External processes holding a "write lock" will
289 * cause udev to skip the event handling; in the case udev
290 * acquired the lock, the external process will block until
291 * udev has finished its event handling.
293 if (streq_ptr("block", udev_device_get_subsystem(dev))) {
294 struct udev_device *d = dev;
296 if (streq_ptr("partition", udev_device_get_devtype(d)))
297 d = udev_device_get_parent(d);
300 fd_lock = open(udev_device_get_devnode(d), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
301 if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {
302 log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));
309 /* apply rules, create node, symlinks */
310 udev_event_execute_rules(udev_event, rules, &sigmask_orig);
312 udev_event_execute_run(udev_event, &sigmask_orig);
314 /* apply/restore inotify watch */
315 if (err == 0 && udev_event->inotify_watch) {
316 udev_watch_begin(udev, dev);
317 udev_device_update_db(dev);
323 /* send processed event back to libudev listeners */
324 udev_monitor_send_device(worker_monitor, NULL, dev);
327 /* send udevd the result of the event execution */
328 memzero(&msg, sizeof(struct worker_message));
331 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
333 log_debug("seq %llu processed with %i", udev_device_get_seqnum(dev), err);
335 udev_device_unref(dev);
338 if (udev_event->sigterm) {
339 udev_event_unref(udev_event);
343 udev_event_unref(udev_event);
345 /* wait for more device messages from main udevd, or term signal */
346 while (dev == NULL) {
347 struct epoll_event ev[4];
351 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
355 log_error("failed to poll: %m");
359 for (i = 0; i < fdcount; i++) {
360 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
361 dev = udev_monitor_receive_device(worker_monitor);
363 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
364 struct signalfd_siginfo fdsi;
367 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
368 if (size != sizeof(struct signalfd_siginfo))
370 switch (fdsi.ssi_signo) {
379 udev_device_unref(dev);
385 close(worker_watch[WRITE_END]);
386 udev_rules_unref(rules);
387 udev_builtin_exit(udev);
388 udev_monitor_unref(worker_monitor);
394 udev_monitor_unref(worker_monitor);
395 event->state = EVENT_QUEUED;
397 log_error("fork of child failed: %m");
400 /* close monitor, but keep address around */
401 udev_monitor_disconnect(worker_monitor);
402 worker->monitor = worker_monitor;
404 worker->state = WORKER_RUNNING;
405 worker->event_start_usec = now(CLOCK_MONOTONIC);
406 worker->event = event;
407 event->state = EVENT_RUNNING;
408 udev_list_node_append(&worker->node, &worker_list);
410 log_debug("seq %llu forked new worker [%u]", udev_device_get_seqnum(event->dev), pid);
415 static void event_run(struct event *event)
417 struct udev_list_node *loop;
419 udev_list_node_foreach(loop, &worker_list) {
420 struct worker *worker = node_to_worker(loop);
423 if (worker->state != WORKER_IDLE)
426 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
428 log_error("worker [%u] did not accept message %zi (%m), kill it", worker->pid, count);
429 kill(worker->pid, SIGKILL);
430 worker->state = WORKER_KILLED;
434 worker->event = event;
435 worker->state = WORKER_RUNNING;
436 worker->event_start_usec = now(CLOCK_MONOTONIC);
437 event->state = EVENT_RUNNING;
441 if (children >= children_max) {
442 if (children_max > 1)
443 log_debug("maximum number (%i) of children reached", children);
447 /* start new worker and pass initial device */
451 static int event_queue_insert(struct udev_device *dev)
455 event = new0(struct event, 1);
459 event->udev = udev_device_get_udev(dev);
461 event->seqnum = udev_device_get_seqnum(dev);
462 event->devpath = udev_device_get_devpath(dev);
463 event->devpath_len = strlen(event->devpath);
464 event->devpath_old = udev_device_get_devpath_old(dev);
465 event->devnum = udev_device_get_devnum(dev);
466 event->is_block = streq("block", udev_device_get_subsystem(dev));
467 event->ifindex = udev_device_get_ifindex(dev);
469 if (streq(udev_device_get_subsystem(dev), "firmware"))
470 event->nodelay = true;
473 log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),
474 udev_device_get_action(dev), udev_device_get_subsystem(dev));
476 event->state = EVENT_QUEUED;
477 udev_list_node_append(&event->node, &event_list);
481 static void worker_kill(struct udev *udev)
483 struct udev_list_node *loop;
485 udev_list_node_foreach(loop, &worker_list) {
486 struct worker *worker = node_to_worker(loop);
488 if (worker->state == WORKER_KILLED)
491 worker->state = WORKER_KILLED;
492 kill(worker->pid, SIGTERM);
496 /* lookup event for identical, parent, child device */
497 static bool is_devpath_busy(struct event *event)
499 struct udev_list_node *loop;
502 /* check if queue contains events we depend on */
503 udev_list_node_foreach(loop, &event_list) {
504 struct event *loop_event = node_to_event(loop);
506 /* we already found a later event, earlier can not block us, no need to check again */
507 if (loop_event->seqnum < event->delaying_seqnum)
510 /* event we checked earlier still exists, no need to check again */
511 if (loop_event->seqnum == event->delaying_seqnum)
514 /* found ourself, no later event can block us */
515 if (loop_event->seqnum >= event->seqnum)
518 /* check major/minor */
519 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
522 /* check network device ifindex */
523 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
526 /* check our old name */
527 if (event->devpath_old != NULL && streq(loop_event->devpath, event->devpath_old)) {
528 event->delaying_seqnum = loop_event->seqnum;
532 /* compare devpath */
533 common = MIN(loop_event->devpath_len, event->devpath_len);
535 /* one devpath is contained in the other? */
536 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
539 /* identical device event found */
540 if (loop_event->devpath_len == event->devpath_len) {
541 /* devices names might have changed/swapped in the meantime */
542 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
544 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
546 event->delaying_seqnum = loop_event->seqnum;
551 /* allow to bypass the dependency tracking */
556 /* parent device event found */
557 if (event->devpath[common] == '/') {
558 event->delaying_seqnum = loop_event->seqnum;
562 /* child device event found */
563 if (loop_event->devpath[common] == '/') {
564 event->delaying_seqnum = loop_event->seqnum;
568 /* no matching device */
575 static void event_queue_start(struct udev *udev)
577 struct udev_list_node *loop;
579 udev_list_node_foreach(loop, &event_list) {
580 struct event *event = node_to_event(loop);
582 if (event->state != EVENT_QUEUED)
585 /* do not start event if parent or child event is still running */
586 if (is_devpath_busy(event))
593 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
595 struct udev_list_node *loop, *tmp;
597 udev_list_node_foreach_safe(loop, tmp, &event_list) {
598 struct event *event = node_to_event(loop);
600 if (match_type != EVENT_UNDEF && match_type != event->state)
603 event_queue_delete(event);
607 static void worker_returned(int fd_worker)
610 struct worker_message msg;
612 struct udev_list_node *loop;
614 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
615 if (size != sizeof(struct worker_message))
618 /* lookup worker who sent the signal */
619 udev_list_node_foreach(loop, &worker_list) {
620 struct worker *worker = node_to_worker(loop);
622 if (worker->pid != msg.pid)
625 /* worker returned */
627 worker->event->exitcode = msg.exitcode;
628 event_queue_delete(worker->event);
629 worker->event = NULL;
631 if (worker->state != WORKER_KILLED)
632 worker->state = WORKER_IDLE;
633 worker_unref(worker);
639 /* receive the udevd message from userspace */
640 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
642 struct udev *udev = udev_ctrl_get_udev(uctrl);
643 struct udev_ctrl_connection *ctrl_conn;
644 struct udev_ctrl_msg *ctrl_msg = NULL;
648 ctrl_conn = udev_ctrl_get_connection(uctrl);
649 if (ctrl_conn == NULL)
652 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
653 if (ctrl_msg == NULL)
656 i = udev_ctrl_get_set_log_level(ctrl_msg);
658 log_debug("udevd message (SET_LOG_LEVEL) received, log_priority=%i", i);
659 log_set_max_level(i);
660 udev_set_log_priority(udev, i);
664 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
665 log_debug("udevd message (STOP_EXEC_QUEUE) received");
666 stop_exec_queue = true;
669 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
670 log_debug("udevd message (START_EXEC_QUEUE) received");
671 stop_exec_queue = false;
674 if (udev_ctrl_get_reload(ctrl_msg) > 0) {
675 log_debug("udevd message (RELOAD) received");
679 str = udev_ctrl_get_set_env(ctrl_msg);
687 val = strchr(key, '=');
691 if (val[0] == '\0') {
692 log_debug("udevd message (ENV) received, unset '%s'", key);
693 udev_add_property(udev, key, NULL);
695 log_debug("udevd message (ENV) received, set '%s=%s'", key, val);
696 udev_add_property(udev, key, val);
699 log_error("wrong key format '%s'", key);
706 i = udev_ctrl_get_set_children_max(ctrl_msg);
708 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i", i);
712 if (udev_ctrl_get_ping(ctrl_msg) > 0)
713 log_debug("udevd message (SYNC) received");
715 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
716 log_debug("udevd message (EXIT) received");
718 /* keep reference to block the client until we exit */
719 udev_ctrl_connection_ref(ctrl_conn);
722 udev_ctrl_msg_unref(ctrl_msg);
723 return udev_ctrl_connection_unref(ctrl_conn);
726 /* read inotify messages */
727 static int handle_inotify(struct udev *udev)
731 struct inotify_event *ev;
733 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
736 buf = malloc(nbytes);
738 log_error("error getting buffer for inotify");
742 nbytes = read(fd_inotify, buf, nbytes);
744 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
745 struct udev_device *dev;
747 ev = (struct inotify_event *)(buf + pos);
748 dev = udev_watch_lookup(udev, ev->wd);
750 log_debug("inotify event: %x for %s", ev->mask, udev_device_get_devnode(dev));
751 if (ev->mask & IN_CLOSE_WRITE) {
752 char filename[UTIL_PATH_SIZE];
755 log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
756 strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
757 fd = open(filename, O_WRONLY|O_CLOEXEC);
759 if (write(fd, "change", 6) < 0)
760 log_debug("error writing uevent: %m");
764 if (ev->mask & IN_IGNORED)
765 udev_watch_end(udev, dev);
767 udev_device_unref(dev);
776 static void handle_signal(struct udev *udev, int signo)
787 struct udev_list_node *loop, *tmp;
789 pid = waitpid(-1, &status, WNOHANG);
793 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
794 struct worker *worker = node_to_worker(loop);
796 if (worker->pid != pid)
798 log_debug("worker [%u] exit", pid);
800 if (WIFEXITED(status)) {
801 if (WEXITSTATUS(status) != 0)
802 log_error("worker [%u] exit with return code %i",
803 pid, WEXITSTATUS(status));
804 } else if (WIFSIGNALED(status)) {
805 log_error("worker [%u] terminated by signal %i (%s)",
806 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
807 } else if (WIFSTOPPED(status)) {
808 log_error("worker [%u] stopped", pid);
809 } else if (WIFCONTINUED(status)) {
810 log_error("worker [%u] continued", pid);
812 log_error("worker [%u] exit with status 0x%04x", pid, status);
815 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
817 log_error("worker [%u] failed while handling '%s'",
818 pid, worker->event->devpath);
819 worker->event->exitcode = -32;
820 event_queue_delete(worker->event);
822 /* drop reference taken for state 'running' */
823 worker_unref(worker);
826 worker_unref(worker);
837 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
839 int ctrl = -1, netlink = -1;
842 n = sd_listen_fds(true);
846 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
847 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
854 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
864 if (ctrl < 0 || netlink < 0)
867 log_debug("ctrl=%i netlink=%i", ctrl, netlink);
874 * read the kernel commandline, in case we need to get into debug mode
875 * udev.log-priority=<level> syslog priority
876 * udev.children-max=<number of workers> events are fully serialized if set to 1
877 * udev.exec-delay=<number of seconds> delay execution of every executed program
879 static void kernel_cmdline_options(struct udev *udev)
881 _cleanup_free_ char *line = NULL;
886 r = proc_cmdline(&line);
888 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
892 FOREACH_WORD_QUOTED(w, l, line, state) {
899 /* accept the same options for the initrd, prefixed with "rd." */
900 if (in_initrd() && startswith(s, "rd."))
905 if (startswith(opt, "udev.log-priority=")) {
908 prio = util_log_priority(opt + 18);
909 log_set_max_level(prio);
910 udev_set_log_priority(udev, prio);
911 } else if (startswith(opt, "udev.children-max=")) {
912 children_max = strtoul(opt + 18, NULL, 0);
913 } else if (startswith(opt, "udev.exec-delay=")) {
914 exec_delay = strtoul(opt + 16, NULL, 0);
921 int main(int argc, char *argv[])
925 int daemonize = false;
926 int resolve_names = 1;
927 static const struct option options[] = {
928 { "daemon", no_argument, NULL, 'd' },
929 { "debug", no_argument, NULL, 'D' },
930 { "children-max", required_argument, NULL, 'c' },
931 { "exec-delay", required_argument, NULL, 'e' },
932 { "resolve-names", required_argument, NULL, 'N' },
933 { "help", no_argument, NULL, 'h' },
934 { "version", no_argument, NULL, 'V' },
940 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
941 struct udev_ctrl_connection *ctrl_conn = NULL;
948 log_set_target(LOG_TARGET_AUTO);
949 log_parse_environment();
952 udev_set_log_fn(udev, udev_main_log);
953 log_set_max_level(udev_get_log_priority(udev));
955 log_debug("version %s", VERSION);
961 option = getopt_long(argc, argv, "c:de:DtN:hV", options, NULL);
970 children_max = strtoul(optarg, NULL, 0);
973 exec_delay = strtoul(optarg, NULL, 0);
977 log_set_max_level(LOG_DEBUG);
978 udev_set_log_priority(udev, LOG_DEBUG);
981 if (streq(optarg, "early")) {
983 } else if (streq(optarg, "late")) {
985 } else if (streq(optarg, "never")) {
988 fprintf(stderr, "resolve-names must be early, late or never\n");
989 log_error("resolve-names must be early, late or never");
994 printf("Usage: udevd OPTIONS\n"
997 " --children-max=<maximum number of workers>\n"
998 " --exec-delay=<seconds to wait before executing RUN=>\n"
999 " --resolve-names=early|late|never\n"
1005 printf("%s\n", VERSION);
1012 kernel_cmdline_options(udev);
1014 if (getuid() != 0) {
1015 fprintf(stderr, "root privileges required\n");
1016 log_error("root privileges required");
1020 /* set umask before creating any file/directory */
1024 mkdir("/run/udev", 0755);
1028 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1032 fd = open("/dev/null", O_RDWR);
1034 if (write(STDOUT_FILENO, 0, 0) < 0)
1035 dup2(fd, STDOUT_FILENO);
1036 if (write(STDERR_FILENO, 0, 0) < 0)
1037 dup2(fd, STDERR_FILENO);
1038 if (fd > STDERR_FILENO)
1041 fprintf(stderr, "cannot open /dev/null\n");
1042 log_error("cannot open /dev/null");
1046 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1047 /* get control and netlink socket from systemd */
1048 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1049 if (udev_ctrl == NULL) {
1050 log_error("error taking over udev control socket");
1055 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1056 if (monitor == NULL) {
1057 log_error("error taking over netlink socket");
1062 /* get our own cgroup, we regularly kill everything udev has left behind */
1063 if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1066 /* open control and netlink socket */
1067 udev_ctrl = udev_ctrl_new(udev);
1068 if (udev_ctrl == NULL) {
1069 fprintf(stderr, "error initializing udev control socket");
1070 log_error("error initializing udev control socket");
1074 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1076 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1077 if (monitor == NULL) {
1078 fprintf(stderr, "error initializing netlink socket\n");
1079 log_error("error initializing netlink socket");
1083 fd_netlink = udev_monitor_get_fd(monitor);
1086 if (udev_monitor_enable_receiving(monitor) < 0) {
1087 fprintf(stderr, "error binding netlink socket\n");
1088 log_error("error binding netlink socket");
1093 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1094 fprintf(stderr, "error binding udev control socket\n");
1095 log_error("error binding udev control socket");
1100 udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024);
1110 log_error("fork of daemon failed: %m");
1115 goto exit_daemonize;
1120 write_string_file("/proc/self/oom_score_adj", "-1000");
1122 sd_notify(1, "READY=1");
1125 print_kmsg("starting version " VERSION "\n");
1130 fd = open("/dev/null", O_RDWR);
1132 dup2(fd, STDIN_FILENO);
1133 dup2(fd, STDOUT_FILENO);
1134 dup2(fd, STDERR_FILENO);
1139 fd_inotify = udev_watch_init(udev);
1140 if (fd_inotify < 0) {
1141 fprintf(stderr, "error initializing inotify\n");
1142 log_error("error initializing inotify");
1146 udev_watch_restore(udev);
1148 /* block and listen to all signals on signalfd */
1150 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1151 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1152 if (fd_signal < 0) {
1153 fprintf(stderr, "error creating signalfd\n");
1154 log_error("error creating signalfd");
1159 /* unnamed socket from workers to the main daemon */
1160 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1161 fprintf(stderr, "error creating socketpair\n");
1162 log_error("error creating socketpair");
1166 fd_worker = worker_watch[READ_END];
1168 udev_builtin_init(udev);
1170 rules = udev_rules_new(udev, resolve_names);
1171 if (rules == NULL) {
1172 log_error("error reading rules");
1176 memzero(&ep_ctrl, sizeof(struct epoll_event));
1177 ep_ctrl.events = EPOLLIN;
1178 ep_ctrl.data.fd = fd_ctrl;
1180 memzero(&ep_inotify, sizeof(struct epoll_event));
1181 ep_inotify.events = EPOLLIN;
1182 ep_inotify.data.fd = fd_inotify;
1184 memzero(&ep_signal, sizeof(struct epoll_event));
1185 ep_signal.events = EPOLLIN;
1186 ep_signal.data.fd = fd_signal;
1188 memzero(&ep_netlink, sizeof(struct epoll_event));
1189 ep_netlink.events = EPOLLIN;
1190 ep_netlink.data.fd = fd_netlink;
1192 memzero(&ep_worker, sizeof(struct epoll_event));
1193 ep_worker.events = EPOLLIN;
1194 ep_worker.data.fd = fd_worker;
1196 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1198 log_error("error creating epoll fd: %m");
1201 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1202 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1203 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1204 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1205 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1206 log_error("fail to add fds to epoll: %m");
1210 if (children_max <= 0) {
1215 if (sched_getaffinity(0, sizeof (cpu_set), &cpu_set) == 0) {
1216 children_max += CPU_COUNT(&cpu_set) * 2;
1219 log_debug("set children_max to %u", children_max);
1221 rc = udev_rules_apply_static_dev_perms(rules);
1223 log_error("failed to apply permissions on static device nodes - %s", strerror(-rc));
1225 udev_list_node_init(&event_list);
1226 udev_list_node_init(&worker_list);
1229 static usec_t last_usec;
1230 struct epoll_event ev[8];
1233 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1237 /* close sources of new events and discard buffered events */
1239 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1242 if (monitor != NULL) {
1243 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1244 udev_monitor_unref(monitor);
1247 if (fd_inotify >= 0) {
1248 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1253 /* discard queued events and kill workers */
1254 event_queue_cleanup(udev, EVENT_QUEUED);
1257 /* exit after all has cleaned up */
1258 if (udev_list_node_is_empty(&event_list) && children == 0)
1261 /* timeout at exit for workers to finish */
1262 timeout = 30 * MSEC_PER_SEC;
1263 } else if (udev_list_node_is_empty(&event_list) && children == 0) {
1267 /* cleanup possible left-over processes in our cgroup */
1269 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1271 /* kill idle or hanging workers */
1272 timeout = 3 * MSEC_PER_SEC;
1275 /* tell settle that we are busy or idle */
1276 if (!udev_list_node_is_empty(&event_list)) {
1279 fd = open("/run/udev/queue", O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
1283 unlink("/run/udev/queue");
1286 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1291 struct udev_list_node *loop;
1295 log_error("timeout, giving up waiting for workers to finish");
1299 /* kill idle workers */
1300 if (udev_list_node_is_empty(&event_list)) {
1301 log_debug("cleanup idle workers");
1305 /* check for hanging events */
1306 udev_list_node_foreach(loop, &worker_list) {
1307 struct worker *worker = node_to_worker(loop);
1309 if (worker->state != WORKER_RUNNING)
1312 if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * USEC_PER_SEC) {
1313 log_error("worker [%u] %s timeout; kill it", worker->pid,
1314 worker->event ? worker->event->devpath : "<idle>");
1315 kill(worker->pid, SIGKILL);
1316 worker->state = WORKER_KILLED;
1318 /* drop reference taken for state 'running' */
1319 worker_unref(worker);
1320 if (worker->event) {
1321 log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1322 worker->event->exitcode = -64;
1323 event_queue_delete(worker->event);
1324 worker->event = NULL;
1331 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1332 for (i = 0; i < fdcount; i++) {
1333 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1335 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1337 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1339 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1341 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1345 /* check for changed config, every 3 seconds at most */
1346 if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) {
1347 if (udev_rules_check_timestamp(rules))
1349 if (udev_builtin_validate(udev))
1352 last_usec = now(CLOCK_MONOTONIC);
1355 /* reload requested, HUP signal received, rules changed, builtin changed */
1358 rules = udev_rules_unref(rules);
1359 udev_builtin_exit(udev);
1363 /* event has finished */
1365 worker_returned(fd_worker);
1368 struct udev_device *dev;
1370 dev = udev_monitor_receive_device(monitor);
1372 udev_device_set_usec_initialized(dev, now(CLOCK_MONOTONIC));
1373 if (event_queue_insert(dev) < 0)
1374 udev_device_unref(dev);
1378 /* start new events */
1379 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1380 udev_builtin_init(udev);
1382 rules = udev_rules_new(udev, resolve_names);
1384 event_queue_start(udev);
1388 struct signalfd_siginfo fdsi;
1391 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1392 if (size == sizeof(struct signalfd_siginfo))
1393 handle_signal(udev, fdsi.ssi_signo);
1396 /* we are shutting down, the events below are not handled anymore */
1400 /* device node watch */
1402 handle_inotify(udev);
1405 * This needs to be after the inotify handling, to make sure,
1406 * that the ping is send back after the possibly generated
1407 * "change" events by the inotify device node watch.
1409 * A single time we may receive a client connection which we need to
1410 * keep open to block the client. It will be closed right before we
1414 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1419 udev_ctrl_cleanup(udev_ctrl);
1420 unlink("/run/udev/queue");
1424 worker_list_cleanup(udev);
1425 event_queue_cleanup(udev, EVENT_UNDEF);
1426 udev_rules_unref(rules);
1427 udev_builtin_exit(udev);
1430 if (worker_watch[READ_END] >= 0)
1431 close(worker_watch[READ_END]);
1432 if (worker_watch[WRITE_END] >= 0)
1433 close(worker_watch[WRITE_END]);
1434 udev_monitor_unref(monitor);
1435 udev_ctrl_connection_unref(ctrl_conn);
1436 udev_ctrl_unref(udev_ctrl);