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"
53 void udev_main_log(struct udev *udev, int priority,
54 const char *file, int line, const char *fn,
55 const char *format, va_list args)
57 log_metav(priority, file, line, fn, format, args);
60 static struct udev_rules *rules;
61 static struct udev_queue_export *udev_queue_export;
62 static struct udev_ctrl *udev_ctrl;
63 static struct udev_monitor *monitor;
64 static int worker_watch[2] = { -1, -1 };
65 static int fd_signal = -1;
66 static int fd_ep = -1;
67 static int fd_inotify = -1;
68 static bool stop_exec_queue;
71 static int children_max;
72 static int exec_delay;
73 static sigset_t sigmask_orig;
74 static UDEV_LIST(event_list);
75 static UDEV_LIST(worker_list);
77 static bool udev_exit;
86 struct udev_list_node node;
88 struct udev_device *dev;
89 enum event_state state;
91 unsigned long long int delaying_seqnum;
92 unsigned long long int seqnum;
95 const char *devpath_old;
101 static struct event *node_to_event(struct udev_list_node *node)
105 event = (char *)node;
106 event -= offsetof(struct event, node);
107 return (struct event *)event;
110 static void event_queue_cleanup(struct udev *udev, enum event_state type);
120 struct udev_list_node node;
124 struct udev_monitor *monitor;
125 enum worker_state state;
127 unsigned long long event_start_usec;
130 /* passed from worker to main process */
131 struct worker_message {
136 static struct worker *node_to_worker(struct udev_list_node *node)
140 worker = (char *)node;
141 worker -= offsetof(struct worker, node);
142 return (struct worker *)worker;
145 static void event_queue_delete(struct event *event, bool export)
147 udev_list_node_remove(&event->node);
150 udev_queue_export_device_finished(udev_queue_export, event->dev);
151 log_debug("seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
153 udev_device_unref(event->dev);
157 static struct worker *worker_ref(struct worker *worker)
163 static void worker_cleanup(struct worker *worker)
165 udev_list_node_remove(&worker->node);
166 udev_monitor_unref(worker->monitor);
171 static void worker_unref(struct worker *worker)
174 if (worker->refcount > 0)
176 log_debug("worker [%u] cleaned up\n", worker->pid);
177 worker_cleanup(worker);
180 static void worker_list_cleanup(struct udev *udev)
182 struct udev_list_node *loop, *tmp;
184 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
185 struct worker *worker = node_to_worker(loop);
187 worker_cleanup(worker);
191 static void worker_new(struct event *event)
193 struct udev *udev = event->udev;
194 struct worker *worker;
195 struct udev_monitor *worker_monitor;
198 /* listen for new events */
199 worker_monitor = udev_monitor_new_from_netlink(udev, NULL);
200 if (worker_monitor == NULL)
202 /* allow the main daemon netlink address to send devices to the worker */
203 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
204 udev_monitor_enable_receiving(worker_monitor);
206 worker = calloc(1, sizeof(struct worker));
207 if (worker == NULL) {
208 udev_monitor_unref(worker_monitor);
211 /* worker + event reference */
212 worker->refcount = 2;
218 struct udev_device *dev = NULL;
220 struct epoll_event ep_signal, ep_monitor;
222 int rc = EXIT_SUCCESS;
224 /* take initial device from queue */
229 worker_list_cleanup(udev);
230 event_queue_cleanup(udev, EVENT_UNDEF);
231 udev_queue_export_unref(udev_queue_export);
232 udev_monitor_unref(monitor);
233 udev_ctrl_unref(udev_ctrl);
236 close(worker_watch[READ_END]);
239 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
241 log_error("error creating signalfd %m\n");
246 fd_ep = epoll_create1(EPOLL_CLOEXEC);
248 log_error("error creating epoll fd: %m\n");
253 memset(&ep_signal, 0, sizeof(struct epoll_event));
254 ep_signal.events = EPOLLIN;
255 ep_signal.data.fd = fd_signal;
257 fd_monitor = udev_monitor_get_fd(worker_monitor);
258 memset(&ep_monitor, 0, sizeof(struct epoll_event));
259 ep_monitor.events = EPOLLIN;
260 ep_monitor.data.fd = fd_monitor;
262 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
263 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {
264 log_error("fail to add fds to epoll: %m\n");
269 /* request TERM signal if parent exits */
270 prctl(PR_SET_PDEATHSIG, SIGTERM);
273 struct udev_event *udev_event;
274 struct worker_message msg;
277 log_debug("seq %llu running\n", udev_device_get_seqnum(dev));
278 udev_event = udev_event_new(dev);
279 if (udev_event == NULL) {
284 /* needed for SIGCHLD/SIGTERM in spawn() */
285 udev_event->fd_signal = fd_signal;
288 udev_event->exec_delay = exec_delay;
290 /* apply rules, create node, symlinks */
291 err = udev_event_execute_rules(udev_event, rules, &sigmask_orig);
294 udev_event_execute_run(udev_event, &sigmask_orig);
296 /* apply/restore inotify watch */
297 if (err == 0 && udev_event->inotify_watch) {
298 udev_watch_begin(udev, dev);
299 udev_device_update_db(dev);
302 /* send processed event back to libudev listeners */
303 udev_monitor_send_device(worker_monitor, NULL, dev);
305 /* send udevd the result of the event execution */
306 memset(&msg, 0, sizeof(struct worker_message));
310 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
312 log_debug("seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
314 udev_device_unref(dev);
317 if (udev_event->sigterm) {
318 udev_event_unref(udev_event);
322 udev_event_unref(udev_event);
324 /* wait for more device messages from main udevd, or term signal */
325 while (dev == NULL) {
326 struct epoll_event ev[4];
330 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
334 log_error("failed to poll: %m\n");
338 for (i = 0; i < fdcount; i++) {
339 if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {
340 dev = udev_monitor_receive_device(worker_monitor);
342 } else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {
343 struct signalfd_siginfo fdsi;
346 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
347 if (size != sizeof(struct signalfd_siginfo))
349 switch (fdsi.ssi_signo) {
358 udev_device_unref(dev);
364 close(worker_watch[WRITE_END]);
365 udev_rules_unref(rules);
366 udev_builtin_exit(udev);
367 udev_monitor_unref(worker_monitor);
373 udev_monitor_unref(worker_monitor);
374 event->state = EVENT_QUEUED;
376 log_error("fork of child failed: %m\n");
379 /* close monitor, but keep address around */
380 udev_monitor_disconnect(worker_monitor);
381 worker->monitor = worker_monitor;
383 worker->state = WORKER_RUNNING;
384 worker->event_start_usec = now_usec();
385 worker->event = event;
386 event->state = EVENT_RUNNING;
387 udev_list_node_append(&worker->node, &worker_list);
389 log_debug("seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
394 static void event_run(struct event *event)
396 struct udev_list_node *loop;
398 udev_list_node_foreach(loop, &worker_list) {
399 struct worker *worker = node_to_worker(loop);
402 if (worker->state != WORKER_IDLE)
405 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
407 log_error("worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
408 kill(worker->pid, SIGKILL);
409 worker->state = WORKER_KILLED;
413 worker->event = event;
414 worker->state = WORKER_RUNNING;
415 worker->event_start_usec = now_usec();
416 event->state = EVENT_RUNNING;
420 if (children >= children_max) {
421 if (children_max > 1)
422 log_debug("maximum number (%i) of children reached\n", children);
426 /* start new worker and pass initial device */
430 static int event_queue_insert(struct udev_device *dev)
434 event = calloc(1, sizeof(struct event));
438 event->udev = udev_device_get_udev(dev);
440 event->seqnum = udev_device_get_seqnum(dev);
441 event->devpath = udev_device_get_devpath(dev);
442 event->devpath_len = strlen(event->devpath);
443 event->devpath_old = udev_device_get_devpath_old(dev);
444 event->devnum = udev_device_get_devnum(dev);
445 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
446 event->ifindex = udev_device_get_ifindex(dev);
448 udev_queue_export_device_queued(udev_queue_export, dev);
449 log_debug("seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
450 udev_device_get_action(dev), udev_device_get_subsystem(dev));
452 event->state = EVENT_QUEUED;
453 udev_list_node_append(&event->node, &event_list);
457 static void worker_kill(struct udev *udev)
459 struct udev_list_node *loop;
461 udev_list_node_foreach(loop, &worker_list) {
462 struct worker *worker = node_to_worker(loop);
464 if (worker->state == WORKER_KILLED)
467 worker->state = WORKER_KILLED;
468 kill(worker->pid, SIGTERM);
472 /* lookup event for identical, parent, child device */
473 static bool is_devpath_busy(struct event *event)
475 struct udev_list_node *loop;
478 /* check if queue contains events we depend on */
479 udev_list_node_foreach(loop, &event_list) {
480 struct event *loop_event = node_to_event(loop);
482 /* we already found a later event, earlier can not block us, no need to check again */
483 if (loop_event->seqnum < event->delaying_seqnum)
486 /* event we checked earlier still exists, no need to check again */
487 if (loop_event->seqnum == event->delaying_seqnum)
490 /* found ourself, no later event can block us */
491 if (loop_event->seqnum >= event->seqnum)
494 /* check major/minor */
495 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
498 /* check network device ifindex */
499 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
502 /* check our old name */
503 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
504 event->delaying_seqnum = loop_event->seqnum;
508 /* compare devpath */
509 common = MIN(loop_event->devpath_len, event->devpath_len);
511 /* one devpath is contained in the other? */
512 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
515 /* identical device event found */
516 if (loop_event->devpath_len == event->devpath_len) {
517 /* devices names might have changed/swapped in the meantime */
518 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
520 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
522 event->delaying_seqnum = loop_event->seqnum;
526 /* parent device event found */
527 if (event->devpath[common] == '/') {
528 event->delaying_seqnum = loop_event->seqnum;
532 /* child device event found */
533 if (loop_event->devpath[common] == '/') {
534 event->delaying_seqnum = loop_event->seqnum;
538 /* no matching device */
545 static void event_queue_start(struct udev *udev)
547 struct udev_list_node *loop;
549 udev_list_node_foreach(loop, &event_list) {
550 struct event *event = node_to_event(loop);
552 if (event->state != EVENT_QUEUED)
555 /* do not start event if parent or child event is still running */
556 if (is_devpath_busy(event))
563 static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
565 struct udev_list_node *loop, *tmp;
567 udev_list_node_foreach_safe(loop, tmp, &event_list) {
568 struct event *event = node_to_event(loop);
570 if (match_type != EVENT_UNDEF && match_type != event->state)
573 event_queue_delete(event, false);
577 static void worker_returned(int fd_worker)
580 struct worker_message msg;
582 struct udev_list_node *loop;
584 size = recv(fd_worker, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
585 if (size != sizeof(struct worker_message))
588 /* lookup worker who sent the signal */
589 udev_list_node_foreach(loop, &worker_list) {
590 struct worker *worker = node_to_worker(loop);
592 if (worker->pid != msg.pid)
595 /* worker returned */
597 worker->event->exitcode = msg.exitcode;
598 event_queue_delete(worker->event, true);
599 worker->event = NULL;
601 if (worker->state != WORKER_KILLED)
602 worker->state = WORKER_IDLE;
603 worker_unref(worker);
609 /* receive the udevd message from userspace */
610 static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
612 struct udev *udev = udev_ctrl_get_udev(uctrl);
613 struct udev_ctrl_connection *ctrl_conn;
614 struct udev_ctrl_msg *ctrl_msg = NULL;
618 ctrl_conn = udev_ctrl_get_connection(uctrl);
619 if (ctrl_conn == NULL)
622 ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);
623 if (ctrl_msg == NULL)
626 i = udev_ctrl_get_set_log_level(ctrl_msg);
628 log_debug("udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
629 log_set_max_level(i);
630 udev_set_log_priority(udev, i);
634 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
635 log_debug("udevd message (STOP_EXEC_QUEUE) received\n");
636 stop_exec_queue = true;
639 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
640 log_debug("udevd message (START_EXEC_QUEUE) received\n");
641 stop_exec_queue = false;
644 if (udev_ctrl_get_reload(ctrl_msg) > 0) {
645 log_debug("udevd message (RELOAD) received\n");
649 str = udev_ctrl_get_set_env(ctrl_msg);
657 val = strchr(key, '=');
661 if (val[0] == '\0') {
662 log_debug("udevd message (ENV) received, unset '%s'\n", key);
663 udev_add_property(udev, key, NULL);
665 log_debug("udevd message (ENV) received, set '%s=%s'\n", key, val);
666 udev_add_property(udev, key, val);
669 log_error("wrong key format '%s'\n", key);
676 i = udev_ctrl_get_set_children_max(ctrl_msg);
678 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
682 if (udev_ctrl_get_ping(ctrl_msg) > 0)
683 log_debug("udevd message (SYNC) received\n");
685 if (udev_ctrl_get_exit(ctrl_msg) > 0) {
686 log_debug("udevd message (EXIT) received\n");
688 /* keep reference to block the client until we exit */
689 udev_ctrl_connection_ref(ctrl_conn);
692 udev_ctrl_msg_unref(ctrl_msg);
693 return udev_ctrl_connection_unref(ctrl_conn);
696 /* read inotify messages */
697 static int handle_inotify(struct udev *udev)
701 struct inotify_event *ev;
703 if ((ioctl(fd_inotify, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
706 buf = malloc(nbytes);
708 log_error("error getting buffer for inotify\n");
712 nbytes = read(fd_inotify, buf, nbytes);
714 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
715 struct udev_device *dev;
717 ev = (struct inotify_event *)(buf + pos);
718 dev = udev_watch_lookup(udev, ev->wd);
720 log_debug("inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
721 if (ev->mask & IN_CLOSE_WRITE) {
722 char filename[UTIL_PATH_SIZE];
725 log_debug("device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
726 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
727 fd = open(filename, O_WRONLY);
729 if (write(fd, "change", 6) < 0)
730 log_debug("error writing uevent: %m\n");
734 if (ev->mask & IN_IGNORED)
735 udev_watch_end(udev, dev);
737 udev_device_unref(dev);
746 static void handle_signal(struct udev *udev, int signo)
757 struct udev_list_node *loop, *tmp;
759 pid = waitpid(-1, &status, WNOHANG);
763 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
764 struct worker *worker = node_to_worker(loop);
766 if (worker->pid != pid)
768 log_debug("worker [%u] exit\n", pid);
770 if (WIFEXITED(status)) {
771 if (WEXITSTATUS(status) != 0)
772 log_error("worker [%u] exit with return code %i\n", pid, WEXITSTATUS(status));
773 } else if (WIFSIGNALED(status)) {
774 log_error("worker [%u] terminated by signal %i (%s)\n",
775 pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
776 } else if (WIFSTOPPED(status)) {
777 log_error("worker [%u] stopped\n", pid);
778 } else if (WIFCONTINUED(status)) {
779 log_error("worker [%u] continued\n", pid);
781 log_error("worker [%u] exit with status 0x%04x\n", pid, status);
784 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
786 log_error("worker [%u] failed while handling '%s'\n",
787 pid, worker->event->devpath);
788 worker->event->exitcode = -32;
789 event_queue_delete(worker->event, true);
790 /* drop reference taken for state 'running' */
791 worker_unref(worker);
794 worker_unref(worker);
805 static void static_dev_create_from_modules(struct udev *udev)
807 struct utsname kernel;
808 char modules[UTIL_PATH_SIZE];
813 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
814 f = fopen(modules, "r");
818 while (fgets(buf, sizeof(buf), f) != NULL) {
826 char filename[UTIL_PATH_SIZE];
832 s = strchr(modname, ' ');
838 s = strchr(devname, ' ');
844 s = strchr(devno, ' ');
846 s = strchr(devno, '\n');
849 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
854 else if (type == 'b')
859 util_strscpyl(filename, sizeof(filename), "/dev/", devname, NULL);
860 util_create_path_selinux(udev, filename);
861 udev_selinux_setfscreatecon(udev, filename, mode);
862 log_debug("mknod '%s' %c%u:%u\n", filename, type, maj, min);
863 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
864 utimensat(AT_FDCWD, filename, NULL, 0);
865 udev_selinux_resetfscreatecon(udev);
871 /* needed for standalone udev operations */
872 static void static_dev_create_links(struct udev *udev)
879 static const struct stdlinks stdlinks[] = {
880 { "core", "/proc/kcore" },
881 { "fd", "/proc/self/fd" },
882 { "stdin", "/proc/self/fd/0" },
883 { "stdout", "/proc/self/fd/1" },
884 { "stderr", "/proc/self/fd/2" },
888 dir = opendir("/dev");
892 for (i = 0; i < ELEMENTSOF(stdlinks); i++) {
895 if (stat(stdlinks[i].target, &sb) == 0) {
896 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
897 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
898 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
899 udev_selinux_resetfscreatecon(udev);
906 static int mem_size_mb(void)
910 long int memsize = -1;
912 f = fopen("/proc/meminfo", "r");
916 while (fgets(buf, sizeof(buf), f) != NULL) {
919 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
920 memsize = value / 1024;
929 static int convert_db(struct udev *udev)
931 char filename[UTIL_PATH_SIZE];
933 struct udev_enumerate *udev_enumerate;
934 struct udev_list_entry *list_entry;
936 /* current database */
937 if (access("/run/udev/data", F_OK) >= 0)
940 /* make sure we do not get here again */
941 util_create_path(udev, "/run/udev/data");
942 mkdir(filename, 0755);
945 util_strscpyl(filename, sizeof(filename), "/dev/.udev/db", NULL);
946 if (access(filename, F_OK) < 0)
949 f = fopen("/dev/kmsg", "w");
951 fprintf(f, "<30>udevd[%u]: converting old udev database\n", getpid());
955 udev_enumerate = udev_enumerate_new(udev);
956 if (udev_enumerate == NULL)
958 udev_enumerate_scan_devices(udev_enumerate);
959 udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
960 struct udev_device *device;
962 device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
966 /* try to find the old database for devices without a current one */
967 if (udev_device_read_db(device, NULL) < 0) {
971 char devpath[UTIL_PATH_SIZE];
972 char from[UTIL_PATH_SIZE];
976 /* find database in old location */
977 id = udev_device_get_id_filename(device);
978 util_strscpyl(from, sizeof(from), "/dev/.udev/db/", id, NULL);
979 if (lstat(from, &stats) == 0) {
981 udev_device_read_db(device, from);
987 /* find old database with $subsys:$sysname name */
988 util_strscpyl(from, sizeof(from), "/dev/.udev/db/",
989 udev_device_get_subsystem(device), ":", udev_device_get_sysname(device), NULL);
990 if (lstat(from, &stats) == 0) {
992 udev_device_read_db(device, from);
998 /* find old database with the encoded devpath name */
999 util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
1000 util_strscpyl(from, sizeof(from), "/dev/.udev/db/", devpath, NULL);
1001 if (lstat(from, &stats) == 0) {
1003 udev_device_read_db(device, from);
1009 /* write out new database */
1011 udev_device_update_db(device);
1013 udev_device_unref(device);
1015 udev_enumerate_unref(udev_enumerate);
1019 static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
1021 int ctrl = -1, netlink = -1;
1024 n = sd_listen_fds(true);
1028 for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
1029 if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
1036 if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
1046 if (ctrl < 0 || netlink < 0)
1049 log_debug("ctrl=%i netlink=%i\n", ctrl, netlink);
1051 *rnetlink = netlink;
1055 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;
1084 log_parse_environment();
1085 udev_set_log_fn(udev, udev_main_log);
1086 log_debug("version %s\n", VERSION);
1087 udev_selinux_init(udev);
1092 option = getopt_long(argc, argv, "c:deDtN:hV", options, NULL);
1101 children_max = strtoul(optarg, NULL, 0);
1104 exec_delay = strtoul(optarg, NULL, 0);
1108 log_set_max_level(LOG_DEBUG);
1109 udev_set_log_priority(udev, LOG_INFO);
1112 if (strcmp (optarg, "early") == 0) {
1114 } else if (strcmp (optarg, "late") == 0) {
1116 } else if (strcmp (optarg, "never") == 0) {
1119 fprintf(stderr, "resolve-names must be early, late or never\n");
1120 log_error("resolve-names must be early, late or never\n");
1125 printf("Usage: udevd OPTIONS\n"
1128 " --children-max=<maximum number of workers>\n"
1129 " --exec-delay=<seconds to wait before executing RUN=>\n"
1130 " --resolve-names=early|late|never\n"
1136 printf("%s\n", VERSION);
1144 * read the kernel commandline, in case we need to get into debug mode
1145 * udev.log-priority=<level> syslog priority
1146 * udev.children-max=<number of workers> events are fully serialized if set to 1
1149 f = fopen("/proc/cmdline", "r");
1153 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1156 pos = strstr(cmdline, "udev.log-priority=");
1158 pos += strlen("udev.log-priority=");
1159 udev_set_log_priority(udev, util_log_priority(pos));
1162 pos = strstr(cmdline, "udev.children-max=");
1164 pos += strlen("udev.children-max=");
1165 children_max = strtoul(pos, NULL, 0);
1168 pos = strstr(cmdline, "udev.exec-delay=");
1170 pos += strlen("udev.exec-delay=");
1171 exec_delay = strtoul(pos, NULL, 0);
1177 if (getuid() != 0) {
1178 fprintf(stderr, "root privileges required\n");
1179 log_error("root privileges required\n");
1183 /* set umask before creating any file/directory */
1187 mkdir("/run/udev", 0755);
1189 /* create standard links, copy static nodes, create nodes from modules */
1190 static_dev_create_links(udev);
1191 static_dev_create_from_modules(udev);
1193 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1197 fd = open("/dev/null", O_RDWR);
1199 if (write(STDOUT_FILENO, 0, 0) < 0)
1200 dup2(fd, STDOUT_FILENO);
1201 if (write(STDERR_FILENO, 0, 0) < 0)
1202 dup2(fd, STDERR_FILENO);
1203 if (fd > STDERR_FILENO)
1206 fprintf(stderr, "cannot open /dev/null\n");
1207 log_error("cannot open /dev/null\n");
1211 if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
1212 /* get control and netlink socket from from systemd */
1213 udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);
1214 if (udev_ctrl == NULL) {
1215 log_error("error taking over udev control socket");
1220 monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
1221 if (monitor == NULL) {
1222 log_error("error taking over netlink socket\n");
1227 /* get our own cgroup, we regularly kill everything udev has left behind */
1228 if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)
1231 /* open control and netlink socket */
1232 udev_ctrl = udev_ctrl_new(udev);
1233 if (udev_ctrl == NULL) {
1234 fprintf(stderr, "error initializing udev control socket");
1235 log_error("error initializing udev control socket");
1239 fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
1241 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1242 if (monitor == NULL) {
1243 fprintf(stderr, "error initializing netlink socket\n");
1244 log_error("error initializing netlink socket\n");
1248 fd_netlink = udev_monitor_get_fd(monitor);
1251 if (udev_monitor_enable_receiving(monitor) < 0) {
1252 fprintf(stderr, "error binding netlink socket\n");
1253 log_error("error binding netlink socket\n");
1258 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1259 fprintf(stderr, "error binding udev control socket\n");
1260 log_error("error binding udev control socket\n");
1265 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1267 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1268 udev_queue_export = udev_queue_export_new(udev);
1269 if (udev_queue_export == NULL) {
1270 log_error("error creating queue file\n");
1283 log_error("fork of daemon failed: %m\n");
1288 goto exit_daemonize;
1293 fd = open("/proc/self/oom_score_adj", O_RDWR);
1295 /* Fallback to old interface */
1296 fd = open("/proc/self/oom_adj", O_RDWR);
1298 log_error("error disabling OOM: %m\n");
1300 /* OOM_DISABLE == -17 */
1301 write(fd, "-17", 3);
1305 write(fd, "-1000", 5);
1309 sd_notify(1, "READY=1");
1312 f = fopen("/dev/kmsg", "w");
1314 fprintf(f, "<30>udevd[%u]: starting version " VERSION "\n", getpid());
1321 fd = open("/dev/null", O_RDWR);
1323 dup2(fd, STDIN_FILENO);
1324 dup2(fd, STDOUT_FILENO);
1325 dup2(fd, STDERR_FILENO);
1330 fd_inotify = udev_watch_init(udev);
1331 if (fd_inotify < 0) {
1332 fprintf(stderr, "error initializing inotify\n");
1333 log_error("error initializing inotify\n");
1337 udev_watch_restore(udev);
1339 /* block and listen to all signals on signalfd */
1341 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);
1342 fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
1343 if (fd_signal < 0) {
1344 fprintf(stderr, "error creating signalfd\n");
1345 log_error("error creating signalfd\n");
1350 /* unnamed socket from workers to the main daemon */
1351 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1352 fprintf(stderr, "error creating socketpair\n");
1353 log_error("error creating socketpair\n");
1357 fd_worker = worker_watch[READ_END];
1359 udev_builtin_init(udev);
1361 rules = udev_rules_new(udev, resolve_names);
1362 if (rules == NULL) {
1363 log_error("error reading rules\n");
1367 memset(&ep_ctrl, 0, sizeof(struct epoll_event));
1368 ep_ctrl.events = EPOLLIN;
1369 ep_ctrl.data.fd = fd_ctrl;
1371 memset(&ep_inotify, 0, sizeof(struct epoll_event));
1372 ep_inotify.events = EPOLLIN;
1373 ep_inotify.data.fd = fd_inotify;
1375 memset(&ep_signal, 0, sizeof(struct epoll_event));
1376 ep_signal.events = EPOLLIN;
1377 ep_signal.data.fd = fd_signal;
1379 memset(&ep_netlink, 0, sizeof(struct epoll_event));
1380 ep_netlink.events = EPOLLIN;
1381 ep_netlink.data.fd = fd_netlink;
1383 memset(&ep_worker, 0, sizeof(struct epoll_event));
1384 ep_worker.events = EPOLLIN;
1385 ep_worker.data.fd = fd_worker;
1387 fd_ep = epoll_create1(EPOLL_CLOEXEC);
1389 log_error("error creating epoll fd: %m\n");
1392 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||
1393 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||
1394 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||
1395 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||
1396 epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {
1397 log_error("fail to add fds to epoll: %m\n");
1401 /* if needed, convert old database from earlier udev version */
1404 if (children_max <= 0) {
1405 int memsize = mem_size_mb();
1407 /* set value depending on the amount of RAM */
1409 children_max = 128 + (memsize / 8);
1413 log_debug("set children_max to %u\n", children_max);
1415 udev_rules_apply_static_dev_perms(rules);
1417 udev_list_node_init(&event_list);
1418 udev_list_node_init(&worker_list);
1421 static unsigned long long last_usec;
1422 struct epoll_event ev[8];
1425 bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;
1429 /* close sources of new events and discard buffered events */
1431 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);
1434 if (monitor != NULL) {
1435 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);
1436 udev_monitor_unref(monitor);
1439 if (fd_inotify >= 0) {
1440 epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);
1445 /* discard queued events and kill workers */
1446 event_queue_cleanup(udev, EVENT_QUEUED);
1449 /* exit after all has cleaned up */
1450 if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list))
1453 /* timeout at exit for workers to finish */
1454 timeout = 30 * 1000;
1455 } else if (udev_list_node_is_empty(&event_list) && !children) {
1459 /* cleanup possible left-over processes in our cgroup */
1461 cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);
1463 /* kill idle or hanging workers */
1466 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
1471 struct udev_list_node *loop;
1475 log_error("timeout, giving up waiting for workers to finish\n");
1479 /* kill idle workers */
1480 if (udev_list_node_is_empty(&event_list)) {
1481 log_debug("cleanup idle workers\n");
1485 /* check for hanging events */
1486 udev_list_node_foreach(loop, &worker_list) {
1487 struct worker *worker = node_to_worker(loop);
1489 if (worker->state != WORKER_RUNNING)
1492 if ((now_usec() - worker->event_start_usec) > 30 * 1000 * 1000) {
1493 log_error("worker [%u] %s timeout; kill it\n", worker->pid,
1494 worker->event ? worker->event->devpath : "<idle>");
1495 kill(worker->pid, SIGKILL);
1496 worker->state = WORKER_KILLED;
1497 /* drop reference taken for state 'running' */
1498 worker_unref(worker);
1499 if (worker->event) {
1500 log_error("seq %llu '%s' killed\n",
1501 udev_device_get_seqnum(worker->event->dev), worker->event->devpath);
1502 worker->event->exitcode = -64;
1503 event_queue_delete(worker->event, true);
1504 worker->event = NULL;
1511 is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;
1512 for (i = 0; i < fdcount; i++) {
1513 if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)
1515 else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)
1517 else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)
1519 else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)
1521 else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)
1525 /* check for changed config, every 3 seconds at most */
1526 if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
1527 if (udev_rules_check_timestamp(rules))
1529 if (udev_builtin_validate(udev))
1532 last_usec = now_usec();
1535 /* reload requested, HUP signal received, rules changed, builtin changed */
1538 rules = udev_rules_unref(rules);
1539 udev_builtin_exit(udev);
1543 /* event has finished */
1545 worker_returned(fd_worker);
1548 struct udev_device *dev;
1550 dev = udev_monitor_receive_device(monitor);
1552 udev_device_set_usec_initialized(dev, now_usec());
1553 if (event_queue_insert(dev) < 0)
1554 udev_device_unref(dev);
1558 /* start new events */
1559 if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {
1561 rules = udev_rules_new(udev, resolve_names);
1563 event_queue_start(udev);
1567 struct signalfd_siginfo fdsi;
1570 size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
1571 if (size == sizeof(struct signalfd_siginfo))
1572 handle_signal(udev, fdsi.ssi_signo);
1575 /* we are shutting down, the events below are not handled anymore */
1579 /* device node watch */
1581 handle_inotify(udev);
1584 * This needs to be after the inotify handling, to make sure,
1585 * that the ping is send back after the possibly generated
1586 * "change" events by the inotify device node watch.
1588 * A single time we may receive a client connection which we need to
1589 * keep open to block the client. It will be closed right before we
1593 ctrl_conn = handle_ctrl_msg(udev_ctrl);
1598 udev_queue_export_cleanup(udev_queue_export);
1599 udev_ctrl_cleanup(udev_ctrl);
1603 worker_list_cleanup(udev);
1604 event_queue_cleanup(udev, EVENT_UNDEF);
1605 udev_rules_unref(rules);
1606 udev_builtin_exit(udev);
1609 if (worker_watch[READ_END] >= 0)
1610 close(worker_watch[READ_END]);
1611 if (worker_watch[WRITE_END] >= 0)
1612 close(worker_watch[WRITE_END]);
1613 udev_monitor_unref(monitor);
1614 udev_queue_export_unref(udev_queue_export);
1615 udev_ctrl_connection_unref(ctrl_conn);
1616 udev_ctrl_unref(udev_ctrl);
1617 udev_selinux_exit(udev);