2 * Copyright (C) 2004-2012 Kay Sievers <kay.sievers@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/>.
35 #include <sys/prctl.h>
36 #include <sys/socket.h>
38 #include <sys/signalfd.h>
39 #include <sys/epoll.h>
43 #include <sys/ioctl.h>
44 #include <sys/inotify.h>
45 #include <sys/utsname.h>
48 #include "sd-daemon.h"
49 #include "cgroup-util.h"
50 #include "dev-setup.h"
54 void udev_main_log(struct udev *udev, int priority,
55 const char *file, int line, const char *fn,
56 const char *format, va_list args)
58 log_metav(priority, file, line, fn, format, args);
61 static struct udev_rules *rules;
62 static struct udev_queue_export *udev_queue_export;
63 static struct udev_ctrl *udev_ctrl;
64 static struct udev_monitor *monitor;
65 static int worker_watch[2] = { -1, -1 };
66 static int fd_signal = -1;
67 static int fd_ep = -1;
68 static int fd_inotify = -1;
69 static bool stop_exec_queue;
72 static int children_max;
73 static int exec_delay;
74 static sigset_t sigmask_orig;
75 static UDEV_LIST(event_list);
76 static UDEV_LIST(worker_list);
78 static bool udev_exit;
87 struct udev_list_node node;
89 struct udev_device *dev;
90 enum event_state state;
92 unsigned long long int delaying_seqnum;
93 unsigned long long int seqnum;
96 const char *devpath_old;
102 static inline struct event *node_to_event(struct udev_list_node *node)
104 return container_of(node, struct event, node);
107 static void event_queue_cleanup(struct udev *udev, enum event_state type);
117 struct udev_list_node node;
121 struct udev_monitor *monitor;
122 enum worker_state state;
124 unsigned long long event_start_usec;
127 /* passed from worker to main process */
128 struct worker_message {
133 static inline struct worker *node_to_worker(struct udev_list_node *node)
135 return container_of(node, struct worker, node);
138 static void event_queue_delete(struct event *event, bool export)
140 udev_list_node_remove(&event->node);
143 udev_queue_export_device_finished(udev_queue_export, event->dev);
144 log_debug("seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
146 udev_device_unref(event->dev);
150 static struct worker *worker_ref(struct worker *worker)
156 static void worker_cleanup(struct worker *worker)
158 udev_list_node_remove(&worker->node);
159 udev_monitor_unref(worker->monitor);
164 static void worker_unref(struct worker *worker)
167 if (worker->refcount > 0)
169 log_debug("worker [%u] cleaned up\n", worker->pid);
170 worker_cleanup(worker);
173 static void worker_list_cleanup(struct udev *udev)
175 struct udev_list_node *loop, *tmp;
177 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
178 struct worker *worker = node_to_worker(loop);
180 worker_cleanup(worker);
184 static void worker_new(struct event *event)
186 struct udev *udev = event->udev;
187 struct worker *worker;
188 struct udev_monitor *worker_monitor;
191 /* listen for new events */
192 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
193 if (worker_monitor == NULL)
195 /* allow the main daemon netlink address to send devices to the worker */
196 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
197 udev_monitor_enable_receiving(worker_monitor);
199 worker = calloc(1, sizeof(struct worker));
200 if (worker == NULL) {
201 udev_monitor_unref(worker_monitor);
204 /* worker + event reference */
205 worker->refcount = 2;
211 struct udev_device *dev = NULL;
213 struct epoll_event ep_signal, ep_monitor;
215 int rc = EXIT_SUCCESS;
217 /* take initial device from queue */
222 worker_list_cleanup(udev);
223 event_queue_cleanup(udev, EVENT_UNDEF);
224 udev_queue_export_unref(udev_queue_export);
225 udev_monitor_unref(monitor);
226 udev_ctrl_unref(udev_ctrl);
229 close(worker_watch[READ_END]);
232 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
234 log_error("error creating signalfd %m\n");
239 fd_ep = epoll_create1(EPOLL_CLOEXEC);
241 log_error("error creating epoll fd: %m\n");
246 memset(&ep_signal, 0, sizeof(struct epoll_event));
247 ep_signal.events = EPOLLIN;
248 ep_signal.data.fd = fd_signal;
250 fd_monitor = udev_monitor_get_fd(worker_monitor);
251 memset(&ep_monitor, 0, sizeof(struct epoll_event));
252 ep_monitor.events = EPOLLIN;
253 ep_monitor.data.fd = fd_monitor;
255 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
256 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
257 log_error("fail to add fds to epoll: %m\n");
262 /* request TERM signal if parent exits */
263 prctl(PR_SET_PDEATHSIG, SIGTERM);
265 /* reset OOM score, we only protect the main daemon */
266 write_one_line_file("/proc/self/oom_score_adj", "0");
269 struct udev_event *udev_event;
270 struct worker_message msg;
273 log_debug("seq %llu running\n", udev_device_get_seqnum(dev));
274 udev_event = udev_event_new(dev);
275 if (udev_event == NULL) {
280 /* needed for SIGCHLD/SIGTERM in spawn() */
281 udev_event->fd_signal = fd_signal;
284 udev_event->exec_delay = exec_delay;
286 /* apply rules, create node, symlinks */
287 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
290 udev_event_execute_run(udev_event, &sigmask_orig);
292 /* apply/restore inotify watch */
293 if (err == 0 && udev_event->inotify_watch) {
294 udev_watch_begin(udev, dev);
295 udev_device_update_db(dev);
298 /* send processed event back to libudev listeners */
299 udev_monitor_send_device(worker_monitor, NULL, dev);
301 /* send udevd the result of the event execution */
302 memset(&msg, 0, sizeof(struct worker_message));
306 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
308 log_debug("seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
310 udev_device_unref(dev);
313 if (udev_event->sigterm) {
314 udev_event_unref(udev_event);
318 udev_event_unref(udev_event);
320 /* wait for more device messages from main udevd, or term signal */
321 while (dev == NULL) {
322 struct epoll_event ev[4];
326 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
330 log_error("failed to poll: %m\n");
334 for (i = 0; i < fdcount; i++) {
335 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
336 dev = udev_monitor_receive_device(worker_monitor);
338 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
339 struct signalfd_siginfo fdsi;
342 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
343 if (size != sizeof(struct signalfd_siginfo))
345 switch (fdsi.ssi_signo) {
354 udev_device_unref(dev);
360 close(worker_watch[WRITE_END]);
361 udev_rules_unref(rules);
362 udev_builtin_exit(udev);
363 udev_monitor_unref(worker_monitor);
369 udev_monitor_unref(worker_monitor);
370 event->state = EVENT_QUEUED;
372 log_error("fork of child failed: %m\n");
375 /* close monitor, but keep address around */
376 udev_monitor_disconnect(worker_monitor);
377 worker->monitor = worker_monitor;
379 worker->state = WORKER_RUNNING;
380 worker->event_start_usec = now_usec();
381 worker->event = event;
382 event->state = EVENT_RUNNING;
383 udev_list_node_append(&worker->node, &worker_list);
385 log_debug("seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
390 static void event_run(struct event *event)
392 struct udev_list_node *loop;
394 udev_list_node_foreach(loop, &worker_list) {
395 struct worker *worker = node_to_worker(loop);
398 if (worker->state != WORKER_IDLE)
401 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
403 log_error("worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
404 kill(worker->pid, SIGKILL);
405 worker->state = WORKER_KILLED;
409 worker->event = event;
410 worker->state = WORKER_RUNNING;
411 worker->event_start_usec = now_usec();
412 event->state = EVENT_RUNNING;
416 if (children >= children_max) {
417 if (children_max > 1)
418 log_debug("maximum number (%i) of children reached\n", children);
422 /* start new worker and pass initial device */
426 static int event_queue_insert(struct udev_device *dev)
430 event = calloc(1, sizeof(struct event));
434 event->udev = udev_device_get_udev(dev);
436 event->seqnum = udev_device_get_seqnum(dev);
437 event->devpath = udev_device_get_devpath(dev);
438 event->devpath_len = strlen(event->devpath);
439 event->devpath_old = udev_device_get_devpath_old(dev);
440 event->devnum = udev_device_get_devnum(dev);
441 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
442 event->ifindex = udev_device_get_ifindex(dev);
444 udev_queue_export_device_queued(udev_queue_export, dev);
445 log_debug("seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
446 udev_device_get_action(dev), udev_device_get_subsystem(dev));
448 event->state = EVENT_QUEUED;
449 udev_list_node_append(&event->node, &event_list);
453 static void worker_kill(struct udev *udev)
455 struct udev_list_node *loop;
457 udev_list_node_foreach(loop, &worker_list) {
458 struct worker *worker = node_to_worker(loop);
460 if (worker->state == WORKER_KILLED)
463 worker->state = WORKER_KILLED;
464 kill(worker->pid, SIGTERM);
468 /* lookup event for identical, parent, child device */
469 static bool is_devpath_busy(struct event *event)
471 struct udev_list_node *loop;
474 /* check if queue contains events we depend on */
475 udev_list_node_foreach(loop, &event_list) {
476 struct event *loop_event = node_to_event(loop);
478 /* we already found a later event, earlier can not block us, no need to check again */
479 if (loop_event->seqnum < event->delaying_seqnum)
482 /* event we checked earlier still exists, no need to check again */
483 if (loop_event->seqnum == event->delaying_seqnum)
486 /* found ourself, no later event can block us */
487 if (loop_event->seqnum >= event->seqnum)
490 /* check major/minor */
491 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
494 /* check network device ifindex */
495 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
498 /* check our old name */
499 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
500 event->delaying_seqnum = loop_event->seqnum;
504 /* compare devpath */
505 common = MIN(loop_event->devpath_len, event->devpath_len);
507 /* one devpath is contained in the other? */
508 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
511 /* identical device event found */
512 if (loop_event->devpath_len == event->devpath_len) {
513 /* devices names might have changed/swapped in the meantime */
514 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
516 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
518 event->delaying_seqnum = loop_event->seqnum;
522 /* parent device event found */
523 if (event->devpath[common] == '/') {
524 event->delaying_seqnum = loop_event->seqnum;
528 /* child device event found */
529 if (loop_event->devpath[common] == '/') {
530 event->delaying_seqnum = loop_event->seqnum;
534 /* no matching device */
541 static void event_queue_start(struct udev *udev)
543 struct udev_list_node *loop;
545 udev_list_node_foreach(loop, &event_list) {
546 struct event *event = node_to_event(loop);
548 if (event->state != EVENT_QUEUED)
551 /* do not start event if parent or child event is still running */
552 if (is_devpath_busy(event))
559 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
561 struct udev_list_node *loop, *tmp;
563 udev_list_node_foreach_safe(loop, tmp, &event_list) {
564 struct event *event = node_to_event(loop);
566 if (match_type != EVENT_UNDEF && match_type != event->state)
569 event_queue_delete(event, false);
573 static void worker_returned(int fd_worker)
576 struct worker_message msg;
578 struct udev_list_node *loop;
580 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
581 if (size != sizeof(struct worker_message))
584 /* lookup worker who sent the signal */
585 udev_list_node_foreach(loop, &worker_list) {
586 struct worker *worker = node_to_worker(loop);
588 if (worker->pid != msg.pid)
591 /* worker returned */
593 worker->event->exitcode = msg.exitcode;
594 event_queue_delete(worker->event, true);
595 worker->event = NULL;
597 if (worker->state != WORKER_KILLED)
598 worker->state = WORKER_IDLE;
599 worker_unref(worker);
605 /* receive the udevd message from userspace */
606 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
608 struct udev *udev = udev_ctrl_get_udev(uctrl);
609 struct udev_ctrl_connection *ctrl_conn;
610 struct udev_ctrl_msg *ctrl_msg = NULL;
614 ctrl_conn = udev_ctrl_get_connection(uctrl);
615 if (ctrl_conn == NULL)
618 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
619 if (ctrl_msg == NULL)
622 i = udev_ctrl_get_set_log_level(ctrl_msg);
624 log_debug("udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
625 log_set_max_level(i);
626 udev_set_log_priority(udev, i);
630 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
631 log_debug("udevd message (STOP_EXEC_QUEUE) received\n");
632 stop_exec_queue = true;
635 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
636 log_debug("udevd message (START_EXEC_QUEUE) received\n");
637 stop_exec_queue = false;
640 if (udev_ctrl_get_reload(ctrl_msg) > 0) {
641 log_debug("udevd message (RELOAD) received\n");
645 str = udev_ctrl_get_set_env(ctrl_msg);
653 val = strchr(key, '=');
657 if (val[0] == '\0') {
658 log_debug("udevd message (ENV) received, unset '%s'\n", key);
659 udev_add_property(udev, key, NULL);
661 log_debug("udevd message (ENV) received, set '%s=%s'\n", key, val);
662 udev_add_property(udev, key, val);
665 log_error("wrong key format '%s'\n", key);
672 i = udev_ctrl_get_set_children_max(ctrl_msg);
674 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
678 if (udev_ctrl_get_ping(ctrl_msg) > 0)
679 log_debug("udevd message (SYNC) received\n");
681 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
682 log_debug("udevd message (EXIT) received\n");
684 /* keep reference to block the client until we exit */
685 udev_ctrl_connection_ref(ctrl_conn);
688 udev_ctrl_msg_unref(ctrl_msg);
689 return udev_ctrl_connection_unref(ctrl_conn);
692 /* read inotify messages */
693 static int handle_inotify(struct udev *udev)
697 struct inotify_event *ev;
699 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
702 buf = malloc(nbytes);
704 log_error("error getting buffer for inotify\n");
708 nbytes = read(fd_inotify, buf, nbytes);
710 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
711 struct udev_device *dev;
713 ev = (struct inotify_event *)(buf + pos);
714 dev = udev_watch_lookup(udev, ev->wd);
716 log_debug("inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
717 if (ev->mask & IN_CLOSE_WRITE) {
718 char filename[UTIL_PATH_SIZE];
721 log_debug("device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
722 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
723 fd = open(filename, O_WRONLY);
725 if (write(fd, "change", 6) < 0)
726 log_debug("error writing uevent: %m\n");
730 if (ev->mask & IN_IGNORED)
731 udev_watch_end(udev, dev);
733 udev_device_unref(dev);
742 static void handle_signal(struct udev *udev, int signo)
753 struct udev_list_node *loop, *tmp;
755 pid = waitpid(-1, &status, WNOHANG);
759 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
760 struct worker *worker = node_to_worker(loop);
762 if (worker->pid != pid)
764 log_debug("worker [%u] exit\n", pid);
766 if (WIFEXITED(status)) {
767 if (WEXITSTATUS(status) != 0)
768 log_error("worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
769 } else if (WIFSIGNALED(status)) {
770 log_error("worker [%u] terminated by signal %i (%s)\n",
771 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
772 } else if (WIFSTOPPED(status)) {
773 log_error("worker [%u] stopped\n", pid);
774 } else if (WIFCONTINUED(status)) {
775 log_error("worker [%u] continued\n", pid);
777 log_error("worker [%u] exit with status 0x%04x\n", pid, status);
780 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
782 log_error("worker [%u] failed while handling '%s'\n",
783 pid, worker->event->devpath);
784 worker->event->exitcode = -32;
785 event_queue_delete(worker->event, true);
786 /* drop reference taken for state 'running' */
787 worker_unref(worker);
790 worker_unref(worker);
801 static void static_dev_create_from_modules(struct udev *udev)
803 struct utsname kernel;
804 char modules[UTIL_PATH_SIZE];
809 util_strscpyl(modules, sizeof(modules), ROOTPREFIX "/lib/modules/", kernel.release, "/modules.devname", NULL);
810 f = fopen(modules, "re");
814 while (fgets(buf, sizeof(buf), f) != NULL) {
822 char filename[UTIL_PATH_SIZE];
828 s = strchr(modname, ' ');
834 s = strchr(devname, ' ');
840 s = strchr(devno, ' ');
842 s = strchr(devno, '\n');
845 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
851 else if (type == 'b')
856 util_strscpyl(filename, sizeof(filename), "/dev/", devname, NULL);
857 mkdir_parents_label(filename, 0755);
858 label_context_set(filename, mode);
859 log_debug("mknod '%s' %c%u:%u\n", filename, type, maj, min);
860 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
861 utimensat(AT_FDCWD, filename, NULL, 0);
862 label_context_clear();
868 static int mem_size_mb(void)
872 long int memsize = -1;
874 f = fopen("/proc/meminfo", "re");
878 while (fgets(buf, sizeof(buf), f) != NULL) {
881 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
882 memsize = value / 1024;
891 static int convert_db(struct udev *udev)
893 char filename[UTIL_PATH_SIZE];
894 struct udev_enumerate *udev_enumerate;
895 struct udev_list_entry *list_entry;
897 /* current database */
898 if (access("/run/udev/data", F_OK) >= 0)
901 /* make sure we do not get here again */
902 mkdir_p("/run/udev/data", 0755);
905 util_strscpyl(filename, sizeof(filename), "/dev/.udev/db", NULL);
906 if (access(filename, F_OK) < 0)
909 print_kmsg("converting old udev database\n");
911 udev_enumerate = udev_enumerate_new(udev);
912 if (udev_enumerate == NULL)
914 udev_enumerate_scan_devices(udev_enumerate);
915 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
916 struct udev_device *device;
918 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
922 /* try to find the old database for devices without a current one */
923 if (udev_device_read_db(device, NULL) < 0) {
927 char devpath[UTIL_PATH_SIZE];
928 char from[UTIL_PATH_SIZE];
932 /* find database in old location */
933 id = udev_device_get_id_filename(device);
934 util_strscpyl(from, sizeof(from), "/dev/.udev/db/", id, NULL);
935 if (lstat(from, &stats) == 0) {
937 udev_device_read_db(device, from);
943 /* find old database with $subsys:$sysname name */
944 util_strscpyl(from, sizeof(from), "/dev/.udev/db/",
945 udev_device_get_subsystem(device), ":", udev_device_get_sysname(device), NULL);
946 if (lstat(from, &stats) == 0) {
948 udev_device_read_db(device, from);
954 /* find old database with the encoded devpath name */
955 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
956 util_strscpyl(from, sizeof(from), "/dev/.udev/db/", devpath, NULL);
957 if (lstat(from, &stats) == 0) {
959 udev_device_read_db(device, from);
965 /* write out new database */
967 udev_device_update_db(device);
969 udev_device_unref(device);
971 udev_enumerate_unref(udev_enumerate);
975 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
977 int ctrl = -1, netlink = -1;
980 n = sd_listen_fds(true);
984 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
985 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
992 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1002 if (ctrl < 0 || netlink < 0)
1005 log_debug("ctrl=%i netlink=%i\n", ctrl, netlink);
1007 *rnetlink = netlink;
1012 * read the kernel commandline, in case we need to get into debug mode
1013 * udev.log-priority=<level> syslog priority
1014 * udev.children-max=<number of workers> events are fully serialized if set to 1
1015 * udev.exec-delay=<number of seconds> delay execution of every executed program
1017 static void kernel_cmdline_options(struct udev *udev)
1019 char *line, *w, *state;
1022 if (read_one_line_file("/proc/cmdline", &line) < 0)
1025 FOREACH_WORD_QUOTED(w, l, line, state) {
1032 /* accept the same options for the initrd, prefixed with "rd." */
1033 if (in_initrd() && startswith(s, "rd."))
1038 if (startswith(opt, "udev.log-priority=")) {
1041 prio = util_log_priority(opt + 18);
1042 log_set_max_level(prio);
1043 udev_set_log_priority(udev, prio);
1044 } else if (startswith(opt, "udev.children-max=")) {
1045 children_max = strtoul(opt + 18, NULL, 0);
1046 } else if (startswith(opt, "udev.exec-delay=")) {
1047 exec_delay = strtoul(opt + 16, NULL, 0);
1056 int main(int argc, char *argv[])
1060 int daemonize = false;
1061 int resolve_names = 1;
1062 static const struct option options[] = {
1063 { "daemon", no_argument, NULL, 'd' },
1064 { "debug", no_argument, NULL, 'D' },
1065 { "children-max", required_argument, NULL, 'c' },
1066 { "exec-delay", required_argument, NULL, 'e' },
1067 { "resolve-names", required_argument, NULL, 'N' },
1068 { "help", no_argument, NULL, 'h' },
1069 { "version", no_argument, NULL, 'V' },
1073 int fd_netlink = -1;
1075 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1076 struct udev_ctrl_connection *ctrl_conn = NULL;
1083 log_set_target(LOG_TARGET_AUTO);
1084 log_parse_environment();
1086 udev_set_log_fn(udev, udev_main_log);
1087 log_debug("version %s\n", VERSION);
1093 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1102 children_max = strtoul(optarg, NULL, 0);
1105 exec_delay = strtoul(optarg, NULL, 0);
1109 log_set_max_level(LOG_DEBUG);
1110 udev_set_log_priority(udev, LOG_DEBUG);
1113 if (strcmp (optarg, "early") == 0) {
1115 } else if (strcmp (optarg, "late") == 0) {
1117 } else if (strcmp (optarg, "never") == 0) {
1120 fprintf(stderr, "resolve-names must be early, late or never\n");
1121 log_error("resolve-names must be early, late or never\n");
1126 printf("Usage: udevd OPTIONS\n"
1129 " --children-max=<maximum number of workers>\n"
1130 " --exec-delay=<seconds to wait before executing RUN=>\n"
1131 " --resolve-names=early|late|never\n"
1137 printf("%s\n", VERSION);
1144 kernel_cmdline_options(udev);
1146 if (getuid() != 0) {
1147 fprintf(stderr, "root privileges required\n");
1148 log_error("root privileges required\n");
1152 /* set umask before creating any file/directory */
1156 mkdir("/run/udev", 0755);
1159 static_dev_create_from_modules(udev);
1161 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1165 fd = open("/dev/null", O_RDWR);
1167 if (write(STDOUT_FILENO, 0, 0) < 0)
1168 dup2(fd, STDOUT_FILENO);
1169 if (write(STDERR_FILENO, 0, 0) < 0)
1170 dup2(fd, STDERR_FILENO);
1171 if (fd > STDERR_FILENO)
1174 fprintf(stderr, "cannot open /dev/null\n");
1175 log_error("cannot open /dev/null\n");
1179 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1180 /* get control and netlink socket from systemd */
1181 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1182 if (udev_ctrl == NULL) {
1183 log_error("error taking over udev control socket");
1188 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1189 if (monitor == NULL) {
1190 log_error("error taking over netlink socket\n");
1195 /* get our own cgroup, we regularly kill everything udev has left behind */
1196 if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1199 /* open control and netlink socket */
1200 udev_ctrl = udev_ctrl_new(udev);
1201 if (udev_ctrl == NULL) {
1202 fprintf(stderr, "error initializing udev control socket");
1203 log_error("error initializing udev control socket");
1207 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1209 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1210 if (monitor == NULL) {
1211 fprintf(stderr, "error initializing netlink socket\n");
1212 log_error("error initializing netlink socket\n");
1216 fd_netlink = udev_monitor_get_fd(monitor);
1219 if (udev_monitor_enable_receiving(monitor) < 0) {
1220 fprintf(stderr, "error binding netlink socket\n");
1221 log_error("error binding netlink socket\n");
1226 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1227 fprintf(stderr, "error binding udev control socket\n");
1228 log_error("error binding udev control socket\n");
1233 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1235 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1236 udev_queue_export = udev_queue_export_new(udev);
1237 if (udev_queue_export == NULL) {
1238 log_error("error creating queue file\n");
1250 log_error("fork of daemon failed: %m\n");
1255 goto exit_daemonize;
1260 write_one_line_file("/proc/self/oom_score_adj", "-1000");
1262 sd_notify(1, "READY=1");
1265 print_kmsg("starting version " VERSION "\n");
1270 fd = open("/dev/null", O_RDWR);
1272 dup2(fd, STDIN_FILENO);
1273 dup2(fd, STDOUT_FILENO);
1274 dup2(fd, STDERR_FILENO);
1279 fd_inotify = udev_watch_init(udev);
1280 if (fd_inotify < 0) {
1281 fprintf(stderr, "error initializing inotify\n");
1282 log_error("error initializing inotify\n");
1286 udev_watch_restore(udev);
1288 /* block and listen to all signals on signalfd */
1290 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1291 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1292 if (fd_signal < 0) {
1293 fprintf(stderr, "error creating signalfd\n");
1294 log_error("error creating signalfd\n");
1299 /* unnamed socket from workers to the main daemon */
1300 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1301 fprintf(stderr, "error creating socketpair\n");
1302 log_error("error creating socketpair\n");
1306 fd_worker = worker_watch[READ_END];
1308 udev_builtin_init(udev);
1310 rules = udev_rules_new(udev, resolve_names);
1311 if (rules == NULL) {
1312 log_error("error reading rules\n");
1316 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1317 ep_ctrl.events = EPOLLIN;
1318 ep_ctrl.data.fd = fd_ctrl;
1320 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1321 ep_inotify.events = EPOLLIN;
1322 ep_inotify.data.fd = fd_inotify;
1324 memset(&ep_signal, 0, sizeof(struct epoll_event));
1325 ep_signal.events = EPOLLIN;
1326 ep_signal.data.fd = fd_signal;
1328 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1329 ep_netlink.events = EPOLLIN;
1330 ep_netlink.data.fd = fd_netlink;
1332 memset(&ep_worker, 0, sizeof(struct epoll_event));
1333 ep_worker.events = EPOLLIN;
1334 ep_worker.data.fd = fd_worker;
1336 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1338 log_error("error creating epoll fd: %m\n");
1341 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1342 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1343 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1344 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1345 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1346 log_error("fail to add fds to epoll: %m\n");
1350 /* if needed, convert old database from earlier udev version */
1353 if (children_max <= 0) {
1354 int memsize = mem_size_mb();
1356 /* set value depending on the amount of RAM */
1358 children_max = 16 + (memsize / 8);
1362 log_debug("set children_max to %u\n", children_max);
1364 udev_rules_apply_static_dev_perms(rules);
1366 udev_list_node_init(&event_list);
1367 udev_list_node_init(&worker_list);
1370 static unsigned long long last_usec;
1371 struct epoll_event ev[8];
1374 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1378 /* close sources of new events and discard buffered events */
1380 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1383 if (monitor != NULL) {
1384 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1385 udev_monitor_unref(monitor);
1388 if (fd_inotify >= 0) {
1389 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1394 /* discard queued events and kill workers */
1395 event_queue_cleanup(udev, EVENT_QUEUED);
1398 /* exit after all has cleaned up */
1399 if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list))
1402 /* timeout at exit for workers to finish */
1403 timeout = 30 * 1000;
1404 } else if (udev_list_node_is_empty(&event_list) && !children) {
1408 /* cleanup possible left-over processes in our cgroup */
1410 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1412 /* kill idle or hanging workers */
1415 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1420 struct udev_list_node *loop;
1424 log_error("timeout, giving up waiting for workers to finish\n");
1428 /* kill idle workers */
1429 if (udev_list_node_is_empty(&event_list)) {
1430 log_debug("cleanup idle workers\n");
1434 /* check for hanging events */
1435 udev_list_node_foreach(loop, &worker_list) {
1436 struct worker *worker = node_to_worker(loop);
1438 if (worker->state != WORKER_RUNNING)
1441 if ((now_usec() - worker->event_start_usec) > 30 * 1000 * 1000) {
1442 log_error("worker [%u] %s timeout; kill it\n", worker->pid,
1443 worker->event ? worker->event->devpath : "<idle>");
1444 kill(worker->pid, SIGKILL);
1445 worker->state = WORKER_KILLED;
1446 /* drop reference taken for state 'running' */
1447 worker_unref(worker);
1448 if (worker->event) {
1449 log_error("seq %llu '%s' killed\n",
1450 udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1451 worker->event->exitcode = -64;
1452 event_queue_delete(worker->event, true);
1453 worker->event = NULL;
1460 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1461 for (i = 0; i < fdcount; i++) {
1462 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1464 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1466 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1468 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1470 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1474 /* check for changed config, every 3 seconds at most */
1475 if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
1476 if (udev_rules_check_timestamp(rules))
1478 if (udev_builtin_validate(udev))
1481 last_usec = now_usec();
1484 /* reload requested, HUP signal received, rules changed, builtin changed */
1487 rules = udev_rules_unref(rules);
1488 udev_builtin_exit(udev);
1492 /* event has finished */
1494 worker_returned(fd_worker);
1497 struct udev_device *dev;
1499 dev = udev_monitor_receive_device(monitor);
1501 udev_device_set_usec_initialized(dev, now_usec());
1502 if (event_queue_insert(dev) < 0)
1503 udev_device_unref(dev);
1507 /* start new events */
1508 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1509 udev_builtin_init(udev);
1511 rules = udev_rules_new(udev, resolve_names);
1513 event_queue_start(udev);
1517 struct signalfd_siginfo fdsi;
1520 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1521 if (size == sizeof(struct signalfd_siginfo))
1522 handle_signal(udev, fdsi.ssi_signo);
1525 /* we are shutting down, the events below are not handled anymore */
1529 /* device node watch */
1531 handle_inotify(udev);
1534 * This needs to be after the inotify handling, to make sure,
1535 * that the ping is send back after the possibly generated
1536 * "change" events by the inotify device node watch.
1538 * A single time we may receive a client connection which we need to
1539 * keep open to block the client. It will be closed right before we
1543 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1548 udev_queue_export_cleanup(udev_queue_export);
1549 udev_ctrl_cleanup(udev_ctrl);
1553 worker_list_cleanup(udev);
1554 event_queue_cleanup(udev, EVENT_UNDEF);
1555 udev_rules_unref(rules);
1556 udev_builtin_exit(udev);
1559 if (worker_watch[READ_END] >= 0)
1560 close(worker_watch[READ_END]);
1561 if (worker_watch[WRITE_END] >= 0)
1562 close(worker_watch[WRITE_END]);
1563 udev_monitor_unref(monitor);
1564 udev_queue_export_unref(udev_queue_export);
1565 udev_ctrl_connection_unref(ctrl_conn);
1566 udev_ctrl_unref(udev_ctrl);