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"
52 void udev_main_log(struct udev *udev, int priority,
53 const char *file, int line, const char *fn,
54 const char *format, va_list args)
56 log_metav(priority, file, line, fn, format, args);
59 static struct udev_rules *rules;
60 static struct udev_queue_export *udev_queue_export;
61 static struct udev_ctrl *udev_ctrl;
62 static struct udev_monitor *monitor;
63 static int worker_watch[2] = { -1, -1 };
64 static int fd_signal = -1;
65 static int fd_ep = -1;
66 static int fd_inotify = -1;
67 static bool stop_exec_queue;
70 static int children_max;
71 static int exec_delay;
72 static sigset_t sigmask_orig;
73 static UDEV_LIST(event_list);
74 static UDEV_LIST(worker_list);
75 static bool udev_exit;
84 struct udev_list_node node;
86 struct udev_device *dev;
87 enum event_state state;
89 unsigned long long int delaying_seqnum;
90 unsigned long long int seqnum;
93 const char *devpath_old;
99 static struct event *node_to_event(struct udev_list_node *node)
103 event = (char *)node;
104 event -= offsetof(struct event, node);
105 return (struct event *)event;
108 static void event_queue_cleanup(struct udev *udev, enum event_state type);
118 struct udev_list_node node;
122 struct udev_monitor *monitor;
123 enum worker_state state;
125 unsigned long long event_start_usec;
128 /* passed from worker to main process */
129 struct worker_message {
134 static struct worker *node_to_worker(struct udev_list_node *node)
138 worker = (char *)node;
139 worker -= offsetof(struct worker, node);
140 return (struct worker *)worker;
143 static void event_queue_delete(struct event *event, bool export)
145 udev_list_node_remove(&event->node);
148 udev_queue_export_device_finished(udev_queue_export, event->dev);
149 log_debug("seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
151 udev_device_unref(event->dev);
155 static struct worker *worker_ref(struct worker *worker)
161 static void worker_cleanup(struct worker *worker)
163 udev_list_node_remove(&worker->node);
164 udev_monitor_unref(worker->monitor);
169 static void worker_unref(struct worker *worker)
172 if (worker->refcount > 0)
174 log_debug("worker [%u] cleaned up\n", worker->pid);
175 worker_cleanup(worker);
178 static void worker_list_cleanup(struct udev *udev)
180 struct udev_list_node *loop, *tmp;
182 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
183 struct worker *worker = node_to_worker(loop);
185 worker_cleanup(worker);
189 static void worker_new(struct event *event)
191 struct udev *udev = event->udev;
192 struct worker *worker;
193 struct udev_monitor *worker_monitor;
196 /* listen for new events */
197 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
198 if (worker_monitor == NULL)
200 /* allow the main daemon netlink address to send devices to the worker */
201 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
202 udev_monitor_enable_receiving(worker_monitor);
204 worker = calloc(1, sizeof(struct worker));
205 if (worker == NULL) {
206 udev_monitor_unref(worker_monitor);
209 /* worker + event reference */
210 worker->refcount = 2;
216 struct udev_device *dev = NULL;
218 struct epoll_event ep_signal, ep_monitor;
220 int rc = EXIT_SUCCESS;
222 /* take initial device from queue */
227 worker_list_cleanup(udev);
228 event_queue_cleanup(udev, EVENT_UNDEF);
229 udev_queue_export_unref(udev_queue_export);
230 udev_monitor_unref(monitor);
231 udev_ctrl_unref(udev_ctrl);
234 close(worker_watch[READ_END]);
237 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
239 log_error("error creating signalfd %m\n");
244 fd_ep = epoll_create1(EPOLL_CLOEXEC);
246 log_error("error creating epoll fd: %m\n");
251 memset(&ep_signal, 0, sizeof(struct epoll_event));
252 ep_signal.events = EPOLLIN;
253 ep_signal.data.fd = fd_signal;
255 fd_monitor = udev_monitor_get_fd(worker_monitor);
256 memset(&ep_monitor, 0, sizeof(struct epoll_event));
257 ep_monitor.events = EPOLLIN;
258 ep_monitor.data.fd = fd_monitor;
260 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
261 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
262 log_error("fail to add fds to epoll: %m\n");
267 /* request TERM signal if parent exits */
268 prctl(PR_SET_PDEATHSIG, SIGTERM);
271 struct udev_event *udev_event;
272 struct worker_message msg;
275 log_debug("seq %llu running\n", udev_device_get_seqnum(dev));
276 udev_event = udev_event_new(dev);
277 if (udev_event == NULL) {
282 /* needed for SIGCHLD/SIGTERM in spawn() */
283 udev_event->fd_signal = fd_signal;
286 udev_event->exec_delay = exec_delay;
288 /* apply rules, create node, symlinks */
289 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
292 udev_event_execute_run(udev_event, &sigmask_orig);
294 /* apply/restore inotify watch */
295 if (err == 0 && udev_event->inotify_watch) {
296 udev_watch_begin(udev, dev);
297 udev_device_update_db(dev);
300 /* send processed event back to libudev listeners */
301 udev_monitor_send_device(worker_monitor, NULL, dev);
303 /* send udevd the result of the event execution */
304 memset(&msg, 0, sizeof(struct worker_message));
308 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
310 log_debug("seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
312 udev_device_unref(dev);
315 if (udev_event->sigterm) {
316 udev_event_unref(udev_event);
320 udev_event_unref(udev_event);
322 /* wait for more device messages from main udevd, or term signal */
323 while (dev == NULL) {
324 struct epoll_event ev[4];
328 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
333 log_error("failed to poll: %m\n");
337 for (i = 0; i < fdcount; i++) {
338 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
339 dev = udev_monitor_receive_device(worker_monitor);
341 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
342 struct signalfd_siginfo fdsi;
345 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
346 if (size != sizeof(struct signalfd_siginfo))
348 switch (fdsi.ssi_signo) {
357 udev_device_unref(dev);
363 close(worker_watch[WRITE_END]);
364 udev_rules_unref(rules);
365 udev_builtin_exit(udev);
366 udev_monitor_unref(worker_monitor);
372 udev_monitor_unref(worker_monitor);
373 event->state = EVENT_QUEUED;
375 log_error("fork of child failed: %m\n");
378 /* close monitor, but keep address around */
379 udev_monitor_disconnect(worker_monitor);
380 worker->monitor = worker_monitor;
382 worker->state = WORKER_RUNNING;
383 worker->event_start_usec = now_usec();
384 worker->event = event;
385 event->state = EVENT_RUNNING;
386 udev_list_node_append(&worker->node, &worker_list);
388 log_debug("seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
393 static void event_run(struct event *event)
395 struct udev_list_node *loop;
397 udev_list_node_foreach(loop, &worker_list) {
398 struct worker *worker = node_to_worker(loop);
401 if (worker->state != WORKER_IDLE)
404 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
406 log_error("worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
407 kill(worker->pid, SIGKILL);
408 worker->state = WORKER_KILLED;
412 worker->event = event;
413 worker->state = WORKER_RUNNING;
414 worker->event_start_usec = now_usec();
415 event->state = EVENT_RUNNING;
419 if (children >= children_max) {
420 if (children_max > 1)
421 log_debug("maximum number (%i) of children reached\n", children);
425 /* start new worker and pass initial device */
429 static int event_queue_insert(struct udev_device *dev)
433 event = calloc(1, sizeof(struct event));
437 event->udev = udev_device_get_udev(dev);
439 event->seqnum = udev_device_get_seqnum(dev);
440 event->devpath = udev_device_get_devpath(dev);
441 event->devpath_len = strlen(event->devpath);
442 event->devpath_old = udev_device_get_devpath_old(dev);
443 event->devnum = udev_device_get_devnum(dev);
444 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
445 event->ifindex = udev_device_get_ifindex(dev);
447 udev_queue_export_device_queued(udev_queue_export, dev);
448 log_debug("seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
449 udev_device_get_action(dev), udev_device_get_subsystem(dev));
451 event->state = EVENT_QUEUED;
452 udev_list_node_append(&event->node, &event_list);
456 static void worker_kill(struct udev *udev, int retain)
458 struct udev_list_node *loop;
461 if (children <= retain)
464 max = children - retain;
466 udev_list_node_foreach(loop, &worker_list) {
467 struct worker *worker = node_to_worker(loop);
472 if (worker->state == WORKER_KILLED)
475 worker->state = WORKER_KILLED;
476 kill(worker->pid, SIGTERM);
480 /* lookup event for identical, parent, child device */
481 static bool is_devpath_busy(struct event *event)
483 struct udev_list_node *loop;
486 /* check if queue contains events we depend on */
487 udev_list_node_foreach(loop, &event_list) {
488 struct event *loop_event = node_to_event(loop);
490 /* we already found a later event, earlier can not block us, no need to check again */
491 if (loop_event->seqnum < event->delaying_seqnum)
494 /* event we checked earlier still exists, no need to check again */
495 if (loop_event->seqnum == event->delaying_seqnum)
498 /* found ourself, no later event can block us */
499 if (loop_event->seqnum >= event->seqnum)
502 /* check major/minor */
503 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
506 /* check network device ifindex */
507 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
510 /* check our old name */
511 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
512 event->delaying_seqnum = loop_event->seqnum;
516 /* compare devpath */
517 common = MIN(loop_event->devpath_len, event->devpath_len);
519 /* one devpath is contained in the other? */
520 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
523 /* identical device event found */
524 if (loop_event->devpath_len == event->devpath_len) {
525 /* devices names might have changed/swapped in the meantime */
526 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
528 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
530 event->delaying_seqnum = loop_event->seqnum;
534 /* parent device event found */
535 if (event->devpath[common] == '/') {
536 event->delaying_seqnum = loop_event->seqnum;
540 /* child device event found */
541 if (loop_event->devpath[common] == '/') {
542 event->delaying_seqnum = loop_event->seqnum;
546 /* no matching device */
553 static void event_queue_start(struct udev *udev)
555 struct udev_list_node *loop;
557 udev_list_node_foreach(loop, &event_list) {
558 struct event *event = node_to_event(loop);
560 if (event->state != EVENT_QUEUED)
563 /* do not start event if parent or child event is still running */
564 if (is_devpath_busy(event))
571 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
573 struct udev_list_node *loop, *tmp;
575 udev_list_node_foreach_safe(loop, tmp, &event_list) {
576 struct event *event = node_to_event(loop);
578 if (match_type != EVENT_UNDEF && match_type != event->state)
581 event_queue_delete(event, false);
585 static void worker_returned(int fd_worker)
588 struct worker_message msg;
590 struct udev_list_node *loop;
592 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
593 if (size != sizeof(struct worker_message))
596 /* lookup worker who sent the signal */
597 udev_list_node_foreach(loop, &worker_list) {
598 struct worker *worker = node_to_worker(loop);
600 if (worker->pid != msg.pid)
603 /* worker returned */
605 worker->event->exitcode = msg.exitcode;
606 event_queue_delete(worker->event, true);
607 worker->event = NULL;
609 if (worker->state != WORKER_KILLED)
610 worker->state = WORKER_IDLE;
611 worker_unref(worker);
617 /* receive the udevd message from userspace */
618 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
620 struct udev *udev = udev_ctrl_get_udev(uctrl);
621 struct udev_ctrl_connection *ctrl_conn;
622 struct udev_ctrl_msg *ctrl_msg = NULL;
626 ctrl_conn = udev_ctrl_get_connection(uctrl);
627 if (ctrl_conn == NULL)
630 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
631 if (ctrl_msg == NULL)
634 i = udev_ctrl_get_set_log_level(ctrl_msg);
636 log_debug("udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
637 log_set_max_level(i);
638 udev_set_log_priority(udev, i);
639 worker_kill(udev, 0);
642 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
643 log_debug("udevd message (STOP_EXEC_QUEUE) received\n");
644 stop_exec_queue = true;
647 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
648 log_debug("udevd message (START_EXEC_QUEUE) received\n");
649 stop_exec_queue = false;
652 if (udev_ctrl_get_reload(ctrl_msg) > 0) {
653 log_debug("udevd message (RELOAD) received\n");
657 str = udev_ctrl_get_set_env(ctrl_msg);
665 val = strchr(key, '=');
669 if (val[0] == '\0') {
670 log_debug("udevd message (ENV) received, unset '%s'\n", key);
671 udev_add_property(udev, key, NULL);
673 log_debug("udevd message (ENV) received, set '%s=%s'\n", key, val);
674 udev_add_property(udev, key, val);
677 log_error("wrong key format '%s'\n", key);
681 worker_kill(udev, 0);
684 i = udev_ctrl_get_set_children_max(ctrl_msg);
686 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
690 if (udev_ctrl_get_ping(ctrl_msg) > 0)
691 log_debug("udevd message (SYNC) received\n");
693 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
694 log_debug("udevd message (EXIT) received\n");
696 /* keep reference to block the client until we exit */
697 udev_ctrl_connection_ref(ctrl_conn);
700 udev_ctrl_msg_unref(ctrl_msg);
701 return udev_ctrl_connection_unref(ctrl_conn);
704 /* read inotify messages */
705 static int handle_inotify(struct udev *udev)
709 struct inotify_event *ev;
711 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
714 buf = malloc(nbytes);
716 log_error("error getting buffer for inotify\n");
720 nbytes = read(fd_inotify, buf, nbytes);
722 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
723 struct udev_device *dev;
725 ev = (struct inotify_event *)(buf + pos);
726 dev = udev_watch_lookup(udev, ev->wd);
728 log_debug("inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
729 if (ev->mask & IN_CLOSE_WRITE) {
730 char filename[UTIL_PATH_SIZE];
733 log_debug("device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
734 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
735 fd = open(filename, O_WRONLY);
737 if (write(fd, "change", 6) < 0)
738 log_debug("error writing uevent: %m\n");
742 if (ev->mask & IN_IGNORED)
743 udev_watch_end(udev, dev);
745 udev_device_unref(dev);
754 static void handle_signal(struct udev *udev, int signo)
765 struct udev_list_node *loop, *tmp;
767 pid = waitpid(-1, &status, WNOHANG);
771 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
772 struct worker *worker = node_to_worker(loop);
774 if (worker->pid != pid)
776 log_debug("worker [%u] exit\n", pid);
778 if (WIFEXITED(status)) {
779 if (WEXITSTATUS(status) != 0)
780 log_error("worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
781 } else if (WIFSIGNALED(status)) {
782 log_error("worker [%u] terminated by signal %i (%s)\n",
783 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
784 } else if (WIFSTOPPED(status)) {
785 log_error("worker [%u] stopped\n", pid);
786 } else if (WIFCONTINUED(status)) {
787 log_error("worker [%u] continued\n", pid);
789 log_error("worker [%u] exit with status 0x%04x\n", pid, status);
792 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
794 log_error("worker [%u] failed while handling '%s'\n",
795 pid, worker->event->devpath);
796 worker->event->exitcode = -32;
797 event_queue_delete(worker->event, true);
798 /* drop reference taken for state 'running' */
799 worker_unref(worker);
802 worker_unref(worker);
813 static void static_dev_create_from_modules(struct udev *udev)
815 struct utsname kernel;
816 char modules[UTIL_PATH_SIZE];
821 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
822 f = fopen(modules, "r");
826 while (fgets(buf, sizeof(buf), f) != NULL) {
834 char filename[UTIL_PATH_SIZE];
840 s = strchr(modname, ' ');
846 s = strchr(devname, ' ');
852 s = strchr(devno, ' ');
854 s = strchr(devno, '\n');
857 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
862 else if (type == 'b')
867 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
868 util_create_path_selinux(udev, filename);
869 udev_selinux_setfscreatecon(udev, filename, mode);
870 log_debug("mknod '%s' %c%u:%u\n", filename, type, maj, min);
871 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
872 utimensat(AT_FDCWD, filename, NULL, 0);
873 udev_selinux_resetfscreatecon(udev);
879 /* needed for standalone udev operations */
880 static void static_dev_create_links(struct udev *udev)
887 static const struct stdlinks stdlinks[] = {
888 { "core", "/proc/kcore" },
889 { "fd", "/proc/self/fd" },
890 { "stdin", "/proc/self/fd/0" },
891 { "stdout", "/proc/self/fd/1" },
892 { "stderr", "/proc/self/fd/2" },
896 dir = opendir(udev_get_dev_path(udev));
900 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
903 if (stat(stdlinks[i].target, &sb) == 0) {
904 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
905 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
906 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
907 udev_selinux_resetfscreatecon(udev);
914 static int mem_size_mb(void)
918 long int memsize = -1;
920 f = fopen("/proc/meminfo", "r");
924 while (fgets(buf, sizeof(buf), f) != NULL) {
927 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
928 memsize = value / 1024;
937 static int convert_db(struct udev *udev)
939 char filename[UTIL_PATH_SIZE];
941 struct udev_enumerate *udev_enumerate;
942 struct udev_list_entry *list_entry;
944 /* current database */
945 util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/data", NULL);
946 if (access(filename, F_OK) >= 0)
949 /* make sure we do not get here again */
950 util_create_path(udev, filename);
951 mkdir(filename, 0755);
954 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db", NULL);
955 if (access(filename, F_OK) < 0)
958 f = fopen("/dev/kmsg", "w");
960 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
964 udev_enumerate = udev_enumerate_new(udev);
965 if (udev_enumerate == NULL)
967 udev_enumerate_scan_devices(udev_enumerate);
968 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
969 struct udev_device *device;
971 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
975 /* try to find the old database for devices without a current one */
976 if (udev_device_read_db(device, NULL) < 0) {
980 char devpath[UTIL_PATH_SIZE];
981 char from[UTIL_PATH_SIZE];
985 /* find database in old location */
986 id = udev_device_get_id_filename(device);
987 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
988 if (lstat(from, &stats) == 0) {
990 udev_device_read_db(device, from);
996 /* find old database with $subsys:$sysname name */
997 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
998 "/.udev/db/", udev_device_get_subsystem(device), ":",
999 udev_device_get_sysname(device), NULL);
1000 if (lstat(from, &stats) == 0) {
1002 udev_device_read_db(device, from);
1008 /* find old database with the encoded devpath name */
1009 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1010 util_strscpyl(from, sizeof(from), udev_get_dev_path(udev), "/.udev/db/", devpath, NULL);
1011 if (lstat(from, &stats) == 0) {
1013 udev_device_read_db(device, from);
1019 /* write out new database */
1021 udev_device_update_db(device);
1023 udev_device_unref(device);
1025 udev_enumerate_unref(udev_enumerate);
1029 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1031 int ctrl = -1, netlink = -1;
1034 n = sd_listen_fds(true);
1038 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1039 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1046 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1056 if (ctrl < 0 || netlink < 0)
1059 log_debug("ctrl=%i netlink=%i\n", ctrl, netlink);
1061 *rnetlink = netlink;
1065 static bool check_rules_timestamp(struct udev *udev)
1068 unsigned long long *stamp_usec;
1070 bool changed = false;
1072 n = udev_get_rules_path(udev, &p, &stamp_usec);
1073 for (i = 0; i < n; i++) {
1076 if (stat(p[i], &stats) < 0)
1079 if (stamp_usec[i] == ts_usec(&stats.st_mtim))
1083 if (stamp_usec[i] != 0) {
1084 log_debug("reload - timestamp of '%s' changed\n", p[i]);
1088 /* update timestamp */
1089 stamp_usec[i] = ts_usec(&stats.st_mtim);
1095 int main(int argc, char *argv[])
1100 int daemonize = false;
1101 int resolve_names = 1;
1102 static const struct option options[] = {
1103 { "daemon", no_argument, NULL, 'd' },
1104 { "debug", no_argument, NULL, 'D' },
1105 { "children-max", required_argument, NULL, 'c' },
1106 { "exec-delay", required_argument, NULL, 'e' },
1107 { "resolve-names", required_argument, NULL, 'N' },
1108 { "help", no_argument, NULL, 'h' },
1109 { "version", no_argument, NULL, 'V' },
1113 int fd_netlink = -1;
1115 struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
1116 struct udev_ctrl_connection *ctrl_conn = NULL;
1124 log_parse_environment();
1125 udev_set_log_fn(udev, udev_main_log);
1126 log_debug("version %s\n", VERSION);
1127 udev_selinux_init(udev);
1132 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1141 children_max = strtoul(optarg, NULL, 0);
1144 exec_delay = strtoul(optarg, NULL, 0);
1148 if (udev_get_log_priority(udev) < LOG_INFO)
1149 udev_set_log_priority(udev, LOG_INFO);
1152 if (strcmp (optarg, "early") == 0) {
1154 } else if (strcmp (optarg, "late") == 0) {
1156 } else if (strcmp (optarg, "never") == 0) {
1159 fprintf(stderr, "resolve-names must be early, late or never\n");
1160 log_error("resolve-names must be early, late or never\n");
1165 printf("Usage: udevd OPTIONS\n"
1168 " --children-max=<maximum number of workers>\n"
1169 " --exec-delay=<seconds to wait before executing RUN=>\n"
1170 " --resolve-names=early|late|never\n"
1176 printf("%s\n", VERSION);
1184 * read the kernel commandline, in case we need to get into debug mode
1185 * udev.log-priority=<level> syslog priority
1186 * udev.children-max=<number of workers> events are fully serialized if set to 1
1189 f = fopen("/proc/cmdline", "r");
1193 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1196 pos = strstr(cmdline, "udev.log-priority=");
1198 pos += strlen("udev.log-priority=");
1199 udev_set_log_priority(udev, util_log_priority(pos));
1202 pos = strstr(cmdline, "udev.children-max=");
1204 pos += strlen("udev.children-max=");
1205 children_max = strtoul(pos, NULL, 0);
1208 pos = strstr(cmdline, "udev.exec-delay=");
1210 pos += strlen("udev.exec-delay=");
1211 exec_delay = strtoul(pos, NULL, 0);
1217 if (getuid() != 0) {
1218 fprintf(stderr, "root privileges required\n");
1219 log_error("root privileges required\n");
1223 /* set umask before creating any file/directory */
1228 mkdir(udev_get_run_path(udev), 0755);
1230 /* create standard links, copy static nodes, create nodes from modules */
1231 static_dev_create_links(udev);
1232 static_dev_create_from_modules(udev);
1234 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1238 fd = open("/dev/null", O_RDWR);
1240 if (write(STDOUT_FILENO, 0, 0) < 0)
1241 dup2(fd, STDOUT_FILENO);
1242 if (write(STDERR_FILENO, 0, 0) < 0)
1243 dup2(fd, STDERR_FILENO);
1244 if (fd > STDERR_FILENO)
1247 fprintf(stderr, "cannot open /dev/null\n");
1248 log_error("cannot open /dev/null\n");
1252 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1253 /* get control and netlink socket from from systemd */
1254 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1255 if (udev_ctrl == NULL) {
1256 log_error("error taking over udev control socket");
1261 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1262 if (monitor == NULL) {
1263 log_error("error taking over netlink socket\n");
1268 /* open control and netlink socket */
1269 udev_ctrl = udev_ctrl_new(udev);
1270 if (udev_ctrl == NULL) {
1271 fprintf(stderr, "error initializing udev control socket");
1272 log_error("error initializing udev control socket");
1276 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1278 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1279 if (monitor == NULL) {
1280 fprintf(stderr, "error initializing netlink socket\n");
1281 log_error("error initializing netlink socket\n");
1285 fd_netlink = udev_monitor_get_fd(monitor);
1288 if (udev_monitor_enable_receiving(monitor) < 0) {
1289 fprintf(stderr, "error binding netlink socket\n");
1290 log_error("error binding netlink socket\n");
1295 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1296 fprintf(stderr, "error binding udev control socket\n");
1297 log_error("error binding udev control socket\n");
1302 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1304 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1305 udev_queue_export = udev_queue_export_new(udev);
1306 if (udev_queue_export == NULL) {
1307 log_error("error creating queue file\n");
1320 log_error("fork of daemon failed: %m\n");
1325 goto exit_daemonize;
1330 fd = open("/proc/self/oom_score_adj", O_RDWR);
1332 /* Fallback to old interface */
1333 fd = open("/proc/self/oom_adj", O_RDWR);
1335 log_error("error disabling OOM: %m\n");
1337 /* OOM_DISABLE == -17 */
1338 write(fd, "-17", 3);
1342 write(fd, "-1000", 5);
1346 sd_notify(1, "READY=1");
1349 f = fopen("/dev/kmsg", "w");
1351 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1358 fd = open("/dev/null", O_RDWR);
1360 dup2(fd, STDIN_FILENO);
1361 dup2(fd, STDOUT_FILENO);
1362 dup2(fd, STDERR_FILENO);
1367 fd_inotify = udev_watch_init(udev);
1368 if (fd_inotify < 0) {
1369 fprintf(stderr, "error initializing inotify\n");
1370 log_error("error initializing inotify\n");
1374 udev_watch_restore(udev);
1376 /* block and listen to all signals on signalfd */
1378 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1379 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1380 if (fd_signal < 0) {
1381 fprintf(stderr, "error creating signalfd\n");
1382 log_error("error creating signalfd\n");
1387 /* unnamed socket from workers to the main daemon */
1388 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1389 fprintf(stderr, "error creating socketpair\n");
1390 log_error("error creating socketpair\n");
1394 fd_worker = worker_watch[READ_END];
1396 udev_builtin_init(udev);
1398 rules = udev_rules_new(udev, resolve_names);
1399 if (rules == NULL) {
1400 log_error("error reading rules\n");
1404 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1405 ep_ctrl.events = EPOLLIN;
1406 ep_ctrl.data.fd = fd_ctrl;
1408 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1409 ep_inotify.events = EPOLLIN;
1410 ep_inotify.data.fd = fd_inotify;
1412 memset(&ep_signal, 0, sizeof(struct epoll_event));
1413 ep_signal.events = EPOLLIN;
1414 ep_signal.data.fd = fd_signal;
1416 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1417 ep_netlink.events = EPOLLIN;
1418 ep_netlink.data.fd = fd_netlink;
1420 memset(&ep_worker, 0, sizeof(struct epoll_event));
1421 ep_worker.events = EPOLLIN;
1422 ep_worker.data.fd = fd_worker;
1424 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1426 log_error("error creating epoll fd: %m\n");
1429 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1430 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1431 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1432 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1433 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1434 log_error("fail to add fds to epoll: %m\n");
1438 /* if needed, convert old database from earlier udev version */
1441 if (children_max <= 0) {
1442 int memsize = mem_size_mb();
1444 /* set value depending on the amount of RAM */
1446 children_max = 128 + (memsize / 8);
1450 log_debug("set children_max to %u\n", children_max);
1452 udev_rules_apply_static_dev_perms(rules);
1454 udev_list_node_init(&event_list);
1455 udev_list_node_init(&worker_list);
1458 static unsigned long long last_usec;
1459 struct epoll_event ev[8];
1462 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1466 /* close sources of new events and discard buffered events */
1468 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1471 if (monitor != NULL) {
1472 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1473 udev_monitor_unref(monitor);
1476 if (fd_inotify >= 0) {
1477 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1482 /* discard queued events and kill workers */
1483 event_queue_cleanup(udev, EVENT_QUEUED);
1484 worker_kill(udev, 0);
1486 /* exit after all has cleaned up */
1487 if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list))
1490 /* timeout at exit for workers to finish */
1491 timeout = 30 * 1000;
1492 } else if (udev_list_node_is_empty(&event_list) && children <= 2) {
1496 /* kill idle or hanging workers */
1499 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
1504 struct udev_list_node *loop;
1508 log_error("timeout, giving up waiting for workers to finish\n");
1512 /* kill idle workers */
1513 if (udev_list_node_is_empty(&event_list)) {
1514 log_debug("cleanup idle workers\n");
1515 worker_kill(udev, 2);
1518 /* check for hanging events */
1519 udev_list_node_foreach(loop, &worker_list) {
1520 struct worker *worker = node_to_worker(loop);
1522 if (worker->state != WORKER_RUNNING)
1525 if ((now_usec() - worker->event_start_usec) > 30 * 1000 * 1000) {
1526 log_error("worker [%u] %s timeout; kill it\n", worker->pid,
1527 worker->event ? worker->event->devpath : "<idle>");
1528 kill(worker->pid, SIGKILL);
1529 worker->state = WORKER_KILLED;
1530 /* drop reference taken for state 'running' */
1531 worker_unref(worker);
1532 if (worker->event) {
1533 log_error("seq %llu '%s' killed\n",
1534 udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1535 worker->event->exitcode = -64;
1536 event_queue_delete(worker->event, true);
1537 worker->event = NULL;
1544 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1545 for (i = 0; i < fdcount; i++) {
1546 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1548 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1550 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1552 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1554 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1558 /* check for changed config, every 3 seconds at most */
1559 if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
1560 if (check_rules_timestamp(udev))
1562 if (udev_builtin_validate(udev))
1565 last_usec = now_usec();
1568 /* reload requested, HUP signal received, rules changed, builtin changed */
1570 worker_kill(udev, 0);
1571 rules = udev_rules_unref(rules);
1572 udev_builtin_exit(udev);
1576 /* event has finished */
1578 worker_returned(fd_worker);
1581 struct udev_device *dev;
1583 dev = udev_monitor_receive_device(monitor);
1585 udev_device_set_usec_initialized(dev, now_usec());
1586 if (event_queue_insert(dev) < 0)
1587 udev_device_unref(dev);
1591 /* start new events */
1592 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1594 rules = udev_rules_new(udev, resolve_names);
1596 event_queue_start(udev);
1600 struct signalfd_siginfo fdsi;
1603 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1604 if (size == sizeof(struct signalfd_siginfo))
1605 handle_signal(udev, fdsi.ssi_signo);
1608 /* we are shutting down, the events below are not handled anymore */
1612 /* device node watch */
1614 handle_inotify(udev);
1617 * This needs to be after the inotify handling, to make sure,
1618 * that the ping is send back after the possibly generated
1619 * "change" events by the inotify device node watch.
1621 * A single time we may receive a client connection which we need to
1622 * keep open to block the client. It will be closed right before we
1626 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1631 udev_queue_export_cleanup(udev_queue_export);
1632 udev_ctrl_cleanup(udev_ctrl);
1636 worker_list_cleanup(udev);
1637 event_queue_cleanup(udev, EVENT_UNDEF);
1638 udev_rules_unref(rules);
1639 udev_builtin_exit(udev);
1642 if (worker_watch[READ_END] >= 0)
1643 close(worker_watch[READ_END]);
1644 if (worker_watch[WRITE_END] >= 0)
1645 close(worker_watch[WRITE_END]);
1646 udev_monitor_unref(monitor);
1647 udev_queue_export_unref(udev_queue_export);
1648 udev_ctrl_connection_unref(ctrl_conn);
1649 udev_ctrl_unref(udev_ctrl);
1650 udev_selinux_exit(udev);