2 * Copyright (C) 2004-2009 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/select.h>
43 #include <sys/ioctl.h>
44 #include <sys/inotify.h>
45 #include <sys/utsname.h>
48 #include "sd-daemon.h"
50 #define UDEVD_PRIORITY -4
51 #define UDEV_PRIORITY -2
55 static void log_fn(struct udev *udev, int priority,
56 const char *file, int line, const char *fn,
57 const char *format, va_list args)
64 vsnprintf(buf, sizeof(buf), format, args);
65 gettimeofday(&tv, &tz);
66 fprintf(stderr, "%llu.%06u [%u] %s: %s",
67 (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
68 (int) getpid(), fn, buf);
70 vsyslog(priority, format, args);
74 static struct udev_rules *rules;
75 static struct udev_queue_export *udev_queue_export;
76 static struct udev_ctrl *udev_ctrl;
77 static struct udev_monitor *monitor;
78 static int worker_watch[2];
79 static pid_t settle_pid;
80 static bool stop_exec_queue;
81 static bool reload_config;
83 static int children_max;
84 static int exec_delay;
85 static sigset_t orig_sigmask;
86 static struct udev_list_node event_list;
87 static struct udev_list_node worker_list;
88 static bool udev_exit;
89 static volatile sig_atomic_t worker_exit;
99 static struct pollfd pfd[] = {
100 [FD_NETLINK] = { .events = POLLIN },
101 [FD_WORKER] = { .events = POLLIN },
102 [FD_SIGNAL] = { .events = POLLIN },
103 [FD_INOTIFY] = { .events = POLLIN },
104 [FD_CONTROL] = { .events = POLLIN },
114 struct udev_list_node node;
116 struct udev_device *dev;
117 enum event_state state;
119 unsigned long long int delaying_seqnum;
120 unsigned long long int seqnum;
123 const char *devpath_old;
129 static struct event *node_to_event(struct udev_list_node *node)
133 event = (char *)node;
134 event -= offsetof(struct event, node);
135 return (struct event *)event;
146 struct udev_list_node node;
150 struct udev_monitor *monitor;
151 enum worker_state state;
155 /* passed from worker to main process */
156 struct worker_message {
161 static struct worker *node_to_worker(struct udev_list_node *node)
165 worker = (char *)node;
166 worker -= offsetof(struct worker, node);
167 return (struct worker *)worker;
170 static void event_queue_delete(struct event *event)
172 udev_list_node_remove(&event->node);
174 /* mark as failed, if "add" event returns non-zero */
175 if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "remove") != 0)
176 udev_queue_export_device_failed(udev_queue_export, event->dev);
178 udev_queue_export_device_finished(udev_queue_export, event->dev);
180 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
181 udev_device_unref(event->dev);
185 static void event_sig_handler(int signum)
197 static struct worker *worker_ref(struct worker *worker)
203 static void worker_unref(struct worker *worker)
206 if (worker->refcount > 0)
209 udev_list_node_remove(&worker->node);
210 udev_monitor_unref(worker->monitor);
212 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
216 static void worker_new(struct event *event)
218 struct worker *worker;
219 struct udev_monitor *worker_monitor;
221 struct sigaction act;
223 /* listen for new events */
224 worker_monitor = udev_monitor_new_from_netlink(event->udev, NULL);
225 if (worker_monitor == NULL)
227 /* allow the main daemon netlink address to send devices to the worker */
228 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
229 udev_monitor_enable_receiving(worker_monitor);
231 worker = calloc(1, sizeof(struct worker));
232 if (worker == NULL) {
233 udev_monitor_unref(worker_monitor);
236 /* worker + event reference */
237 worker->refcount = 2;
238 worker->udev = event->udev;
244 struct udev_device *dev;
245 struct pollfd pmon = {
246 .fd = udev_monitor_get_fd(worker_monitor),
250 udev_queue_export_unref(udev_queue_export);
251 udev_monitor_unref(monitor);
252 udev_ctrl_unref(udev_ctrl);
253 close(pfd[FD_SIGNAL].fd);
254 close(worker_watch[READ_END]);
256 udev_log_init("udevd-work");
257 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
259 /* set signal handlers */
260 memset(&act, 0x00, sizeof(act));
261 act.sa_handler = event_sig_handler;
262 sigemptyset (&act.sa_mask);
264 sigaction(SIGTERM, &act, NULL);
265 sigaction(SIGALRM, &act, NULL);
267 /* unblock SIGALRM */
268 sigfillset(&sigmask);
269 sigdelset(&sigmask, SIGALRM);
270 sigprocmask(SIG_SETMASK, &sigmask, NULL);
271 /* SIGTERM is unblocked in ppoll() */
272 sigdelset(&sigmask, SIGTERM);
274 /* request TERM signal if parent exits */
275 prctl(PR_SET_PDEATHSIG, SIGTERM);
281 struct udev_event *udev_event;
282 struct worker_message msg = {};
286 info(event->udev, "seq %llu running\n", udev_device_get_seqnum(dev));
287 udev_event = udev_event_new(dev);
288 if (udev_event == NULL)
291 /* set timeout to prevent hanging processes */
292 alarm(UDEV_EVENT_TIMEOUT);
295 udev_event->exec_delay = exec_delay;
297 /* apply rules, create node, symlinks */
298 err = udev_event_execute_rules(udev_event, rules);
300 /* rules may change/disable the timeout */
301 if (udev_device_get_event_timeout(dev) >= 0)
302 alarm(udev_device_get_event_timeout(dev));
305 failed = udev_event_execute_run(udev_event, &orig_sigmask);
309 /* apply/restore inotify watch */
310 if (err == 0 && udev_event->inotify_watch) {
311 udev_watch_begin(udev_event->udev, dev);
312 udev_device_update_db(dev);
315 /* send processed event back to libudev listeners */
316 udev_monitor_send_device(worker_monitor, NULL, dev);
318 /* send udevd the result of the event execution */
321 else if (failed != 0)
322 msg.exitcode = failed;
324 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
326 info(event->udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
327 udev_event_unref(udev_event);
328 udev_device_unref(dev);
331 /* wait for more device messages or signal from udevd */
332 while (!worker_exit) {
335 fdcount = ppoll(&pmon, 1, NULL, &sigmask);
339 if (pmon.revents & POLLIN) {
340 dev = udev_monitor_receive_device(worker_monitor);
345 } while (dev != NULL);
347 udev_monitor_unref(worker_monitor);
352 udev_monitor_unref(worker_monitor);
353 event->state = EVENT_QUEUED;
355 err(event->udev, "fork of child failed: %m\n");
358 /* close monitor, but keep address around */
359 udev_monitor_disconnect(worker_monitor);
360 worker->monitor = worker_monitor;
362 worker->state = WORKER_RUNNING;
363 worker->event = event;
364 event->state = EVENT_RUNNING;
365 udev_list_node_append(&worker->node, &worker_list);
367 info(event->udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
372 static void event_run(struct event *event, bool force)
374 struct udev_list_node *loop;
376 udev_list_node_foreach(loop, &worker_list) {
377 struct worker *worker = node_to_worker(loop);
380 if (worker->state != WORKER_IDLE)
383 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
385 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
386 kill(worker->pid, SIGKILL);
387 worker->state = WORKER_KILLED;
391 worker->event = event;
392 worker->state = WORKER_RUNNING;
393 event->state = EVENT_RUNNING;
397 if (!force && children >= children_max) {
398 if (children_max > 1)
399 info(event->udev, "maximum number (%i) of children reached\n", children);
403 /* start new worker and pass initial device */
407 static int event_queue_insert(struct udev_device *dev)
411 event = calloc(1, sizeof(struct event));
415 event->udev = udev_device_get_udev(dev);
417 event->seqnum = udev_device_get_seqnum(dev);
418 event->devpath = udev_device_get_devpath(dev);
419 event->devpath_len = strlen(event->devpath);
420 event->devpath_old = udev_device_get_devpath_old(dev);
421 event->devnum = udev_device_get_devnum(dev);
422 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
423 event->ifindex = udev_device_get_ifindex(dev);
425 udev_queue_export_device_queued(udev_queue_export, dev);
426 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
427 udev_device_get_action(dev), udev_device_get_subsystem(dev));
429 event->state = EVENT_QUEUED;
430 udev_list_node_append(&event->node, &event_list);
432 /* run all events with a timeout set immediately */
433 if (udev_device_get_timeout(dev) > 0) {
434 event_run(event, true);
441 static void worker_kill(struct udev *udev, int retain)
443 struct udev_list_node *loop;
446 if (children <= retain)
449 max = children - retain;
451 udev_list_node_foreach(loop, &worker_list) {
452 struct worker *worker = node_to_worker(loop);
457 if (worker->state == WORKER_KILLED)
460 worker->state = WORKER_KILLED;
461 kill(worker->pid, SIGTERM);
465 /* lookup event for identical, parent, child device */
466 static bool is_devpath_busy(struct event *event)
468 struct udev_list_node *loop;
471 /* check if queue contains events we depend on */
472 udev_list_node_foreach(loop, &event_list) {
473 struct event *loop_event = node_to_event(loop);
475 /* we already found a later event, earlier can not block us, no need to check again */
476 if (loop_event->seqnum < event->delaying_seqnum)
479 /* event we checked earlier still exists, no need to check again */
480 if (loop_event->seqnum == event->delaying_seqnum)
483 /* found ourself, no later event can block us */
484 if (loop_event->seqnum >= event->seqnum)
487 /* check major/minor */
488 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
491 /* check network device ifindex */
492 if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)
495 /* check our old name */
496 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
497 event->delaying_seqnum = loop_event->seqnum;
501 /* compare devpath */
502 common = MIN(loop_event->devpath_len, event->devpath_len);
504 /* one devpath is contained in the other? */
505 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
508 /* identical device event found */
509 if (loop_event->devpath_len == event->devpath_len) {
510 /* devices names might have changed/swapped in the meantime */
511 if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))
513 if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)
515 event->delaying_seqnum = loop_event->seqnum;
519 /* parent device event found */
520 if (event->devpath[common] == '/') {
521 event->delaying_seqnum = loop_event->seqnum;
525 /* child device event found */
526 if (loop_event->devpath[common] == '/') {
527 event->delaying_seqnum = loop_event->seqnum;
531 /* no matching device */
538 static void events_start(struct udev *udev)
540 struct udev_list_node *loop;
542 udev_list_node_foreach(loop, &event_list) {
543 struct event *event = node_to_event(loop);
545 if (event->state != EVENT_QUEUED)
548 /* do not start event if parent or child event is still running */
549 if (is_devpath_busy(event)) {
550 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
554 event_run(event, false);
558 static void worker_returned(void)
561 struct worker_message msg;
563 struct udev_list_node *loop;
565 size = recv(pfd[FD_WORKER].fd, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
566 if (size != sizeof(struct worker_message))
569 /* lookup worker who sent the signal */
570 udev_list_node_foreach(loop, &worker_list) {
571 struct worker *worker = node_to_worker(loop);
573 if (worker->pid != msg.pid)
576 /* worker returned */
577 worker->event->exitcode = msg.exitcode;
578 event_queue_delete(worker->event);
579 worker->event = NULL;
580 if (worker->state != WORKER_KILLED)
581 worker->state = WORKER_IDLE;
582 worker_unref(worker);
588 /* receive the udevd message from userspace */
589 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
591 struct udev *udev = udev_ctrl_get_udev(uctrl);
592 struct udev_ctrl_msg *ctrl_msg;
596 ctrl_msg = udev_ctrl_receive_msg(uctrl);
597 if (ctrl_msg == NULL)
600 i = udev_ctrl_get_set_log_level(ctrl_msg);
602 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
603 udev_set_log_priority(udev, i);
604 worker_kill(udev, 0);
607 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
608 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
609 stop_exec_queue = true;
612 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
613 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
614 stop_exec_queue = false;
617 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
618 info(udev, "udevd message (RELOAD_RULES) received\n");
619 reload_config = true;
622 str = udev_ctrl_get_set_env(ctrl_msg);
630 val = strchr(key, '=');
634 if (val[0] == '\0') {
635 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
636 udev_add_property(udev, key, NULL);
638 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
639 udev_add_property(udev, key, val);
642 err(udev, "wrong key format '%s'\n", key);
646 worker_kill(udev, 0);
649 i = udev_ctrl_get_set_children_max(ctrl_msg);
651 info(udev, "udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i);
655 settle_pid = udev_ctrl_get_settle(ctrl_msg);
656 if (settle_pid > 0) {
657 info(udev, "udevd message (SETTLE) received\n");
658 kill(settle_pid, SIGUSR1);
661 udev_ctrl_msg_unref(ctrl_msg);
664 /* read inotify messages */
665 static int handle_inotify(struct udev *udev)
669 struct inotify_event *ev;
671 if ((ioctl(pfd[FD_INOTIFY].fd, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
674 buf = malloc(nbytes);
676 err(udev, "error getting buffer for inotify\n");
680 nbytes = read(pfd[FD_INOTIFY].fd, buf, nbytes);
682 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
683 struct udev_device *dev;
685 ev = (struct inotify_event *)(buf + pos);
689 info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
690 s = strstr(ev->name, ".rules");
693 if (strlen(s) != strlen(".rules"))
695 reload_config = true;
699 dev = udev_watch_lookup(udev, ev->wd);
701 info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
702 if (ev->mask & IN_CLOSE_WRITE) {
703 char filename[UTIL_PATH_SIZE];
706 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
707 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
708 fd = open(filename, O_WRONLY);
709 if (fd < 0 || write(fd, "change", 6) < 0)
710 info(udev, "error writing uevent: %m\n");
713 if (ev->mask & IN_IGNORED)
714 udev_watch_end(udev, dev);
716 udev_device_unref(dev);
725 static void handle_signal(struct udev *udev, int signo)
736 struct udev_list_node *loop, *tmp;
738 pid = waitpid(-1, &status, WNOHANG);
742 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
743 struct worker *worker = node_to_worker(loop);
745 if (worker->pid != pid)
748 info(udev, "worker [%u] exit\n", pid);
749 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
750 err(udev, "worker [%u] unexpectedly returned with status 0x%04x\n", pid, status);
751 if (worker->event != NULL) {
752 err(udev, "worker [%u] failed while handling '%s'\n", pid, worker->event->devpath);
753 worker->event->exitcode = -32;
754 event_queue_delete(worker->event);
755 /* drop reference from running event */
756 worker_unref(worker);
759 worker_unref(worker);
765 reload_config = true;
770 static void static_dev_create_from_modules(struct udev *udev)
772 struct utsname kernel;
773 char modules[UTIL_PATH_SIZE];
778 util_strscpyl(modules, sizeof(modules), "/lib/modules/", kernel.release, "/modules.devname", NULL);
779 f = fopen(modules, "r");
783 while (fgets(buf, sizeof(buf), f) != NULL) {
791 char filename[UTIL_PATH_SIZE];
797 s = strchr(modname, ' ');
803 s = strchr(devname, ' ');
809 s = strchr(devno, ' ');
811 s = strchr(devno, '\n');
814 if (sscanf(devno, "%c%u:%u", &type, &maj, &min) != 3)
818 mode = 0600 | S_IFCHR;
819 else if (type == 'b')
820 mode = 0600 | S_IFBLK;
824 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/", devname, NULL);
825 util_create_path(udev, filename);
826 udev_selinux_setfscreatecon(udev, filename, mode);
827 info(udev, "mknod '%s' %c%u:%u\n", filename, type, maj, min);
828 if (mknod(filename, mode, makedev(maj, min)) < 0 && errno == EEXIST)
829 utimensat(AT_FDCWD, filename, NULL, 0);
830 udev_selinux_resetfscreatecon(udev);
836 static int copy_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
840 for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
843 if (dent->d_name[0] == '.')
845 if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
848 if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
849 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
850 if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
851 fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
852 fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
854 utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
856 udev_selinux_resetfscreatecon(udev);
857 } else if (S_ISLNK(stats.st_mode)) {
858 char target[UTIL_PATH_SIZE];
861 len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
862 if (len <= 0 || len == (ssize_t)sizeof(target))
865 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
866 if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
867 utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
868 udev_selinux_resetfscreatecon(udev);
869 } else if (S_ISDIR(stats.st_mode)) {
870 DIR *dir2_from, *dir2_to;
875 udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
876 mkdirat(dirfd(dir_to), dent->d_name, 0755);
877 udev_selinux_resetfscreatecon(udev);
879 dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
883 dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
884 if (dir2_from == NULL) {
889 copy_dir(udev, dir2_from, dir2_to, maxdepth-1);
899 static void static_dev_create_links(struct udev *udev, DIR *dir)
905 static const struct stdlinks stdlinks[] = {
906 { "core", "/proc/kcore" },
907 { "fd", "/proc/self/fd" },
908 { "stdin", "/proc/self/fd/0" },
909 { "stdout", "/proc/self/fd/1" },
910 { "stderr", "/proc/self/fd/2" },
914 for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
917 if (stat(stdlinks[i].target, &sb) == 0) {
918 udev_selinux_setfscreateconat(udev, dirfd(dir), stdlinks[i].link, S_IFLNK);
919 if (symlinkat(stdlinks[i].target, dirfd(dir), stdlinks[i].link) < 0 && errno == EEXIST)
920 utimensat(dirfd(dir), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
921 udev_selinux_resetfscreatecon(udev);
926 static void static_dev_create_from_devices(struct udev *udev, DIR *dir)
930 dir_from = opendir(LIBEXECDIR "/devices");
931 if (dir_from == NULL)
933 copy_dir(udev, dir_from, dir, 8);
937 static void static_dev_create(struct udev *udev)
941 dir = opendir(udev_get_dev_path(udev));
945 static_dev_create_links(udev, dir);
946 static_dev_create_from_devices(udev, dir);
951 static int mem_size_mb(void)
955 long int memsize = -1;
957 f = fopen("/proc/meminfo", "r");
961 while (fgets(buf, sizeof(buf), f) != NULL) {
964 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
965 memsize = value / 1024;
974 int main(int argc, char *argv[])
980 int daemonize = false;
981 int resolve_names = 1;
982 static const struct option options[] = {
983 { "daemon", no_argument, NULL, 'd' },
984 { "debug", no_argument, NULL, 'D' },
985 { "children-max", required_argument, NULL, 'c' },
986 { "exec-delay", required_argument, NULL, 'e' },
987 { "resolve-names", required_argument, NULL, 'N' },
988 { "help", no_argument, NULL, 'h' },
989 { "version", no_argument, NULL, 'V' },
998 udev_log_init("udevd");
999 udev_set_log_fn(udev, log_fn);
1000 info(udev, "version %s\n", VERSION);
1001 udev_selinux_init(udev);
1006 option = getopt_long(argc, argv, "c:deDthV", options, NULL);
1015 children_max = strtoul(optarg, NULL, 0);
1018 exec_delay = strtoul(optarg, NULL, 0);
1022 if (udev_get_log_priority(udev) < LOG_INFO)
1023 udev_set_log_priority(udev, LOG_INFO);
1026 if (strcmp (optarg, "early") == 0) {
1028 } else if (strcmp (optarg, "late") == 0) {
1030 } else if (strcmp (optarg, "never") == 0) {
1033 fprintf(stderr, "resolve-names must be early, late or never\n");
1034 err(udev, "resolve-names must be early, late or never\n");
1039 printf("Usage: udevd OPTIONS\n"
1042 " --children-max=<maximum number of workers>\n"
1043 " --exec-delay=<seconds to wait before executing RUN=>\n"
1044 " --resolve-names=early|late|never\n"
1050 printf("%s\n", VERSION);
1058 * read the kernel commandline, in case we need to get into debug mode
1059 * udev.log-priority=<level> syslog priority
1060 * udev.children-max=<number of workers> events are fully serialized if set to 1
1063 f = fopen("/proc/cmdline", "r");
1067 if (fgets(cmdline, sizeof(cmdline), f) != NULL) {
1070 pos = strstr(cmdline, "udev.log-priority=");
1072 pos += strlen("udev.log-priority=");
1073 udev_set_log_priority(udev, util_log_priority(pos));
1076 pos = strstr(cmdline, "udev.children-max=");
1078 pos += strlen("udev.children-max=");
1079 children_max = strtoul(pos, NULL, 0);
1082 pos = strstr(cmdline, "udev.exec-delay=");
1084 pos += strlen("udev.exec-delay=");
1085 exec_delay = strtoul(pos, NULL, 0);
1091 if (getuid() != 0) {
1092 fprintf(stderr, "root privileges required\n");
1093 err(udev, "root privileges required\n");
1097 /* set umask before creating any file/directory */
1101 /* create standard links, copy static nodes, create nodes from modules */
1102 static_dev_create(udev);
1103 static_dev_create_from_modules(udev);
1105 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1106 fd = open("/dev/null", O_RDWR);
1108 fprintf(stderr, "cannot open /dev/null\n");
1109 err(udev, "cannot open /dev/null\n");
1111 if (write(STDOUT_FILENO, 0, 0) < 0)
1112 dup2(fd, STDOUT_FILENO);
1113 if (write(STDERR_FILENO, 0, 0) < 0)
1114 dup2(fd, STDERR_FILENO);
1116 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
1117 if (udev_ctrl == NULL) {
1118 fprintf(stderr, "error initializing control socket");
1119 err(udev, "error initializing udevd socket");
1123 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
1124 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
1125 err(udev, "error binding control socket, seems udevd is already running\n");
1129 pfd[FD_CONTROL].fd = udev_ctrl_get_fd(udev_ctrl);
1131 monitor = udev_monitor_new_from_netlink(udev, "kernel");
1132 if (monitor == NULL || udev_monitor_enable_receiving(monitor) < 0) {
1133 fprintf(stderr, "error initializing netlink socket\n");
1134 err(udev, "error initializing netlink socket\n");
1138 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
1139 pfd[FD_NETLINK].fd = udev_monitor_get_fd(monitor);
1141 pfd[FD_INOTIFY].fd = udev_watch_init(udev);
1142 if (pfd[FD_INOTIFY].fd < 0) {
1143 fprintf(stderr, "error initializing inotify\n");
1144 err(udev, "error initializing inotify\n");
1149 if (udev_get_rules_path(udev) != NULL) {
1150 inotify_add_watch(pfd[FD_INOTIFY].fd, udev_get_rules_path(udev),
1151 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1153 char filename[UTIL_PATH_SIZE];
1154 struct stat statbuf;
1156 inotify_add_watch(pfd[FD_INOTIFY].fd, LIBEXECDIR "/rules.d",
1157 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1158 inotify_add_watch(pfd[FD_INOTIFY].fd, SYSCONFDIR "/udev/rules.d",
1159 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1161 /* watch dynamic rules directory */
1162 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/rules.d", NULL);
1163 if (stat(filename, &statbuf) != 0) {
1164 util_create_path(udev, filename);
1165 udev_selinux_setfscreatecon(udev, filename, S_IFDIR|0755);
1166 mkdir(filename, 0755);
1167 udev_selinux_resetfscreatecon(udev);
1169 inotify_add_watch(pfd[FD_INOTIFY].fd, filename,
1170 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1172 udev_watch_restore(udev);
1174 /* block and listen to all signals on signalfd */
1176 sigprocmask(SIG_SETMASK, &mask, &orig_sigmask);
1177 pfd[FD_SIGNAL].fd = signalfd(-1, &mask, 0);
1178 if (pfd[FD_SIGNAL].fd < 0) {
1179 fprintf(stderr, "error getting signalfd\n");
1180 err(udev, "error getting signalfd\n");
1185 /* unnamed socket from workers to the main daemon */
1186 if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
1187 fprintf(stderr, "error getting socketpair\n");
1188 err(udev, "error getting socketpair\n");
1192 pfd[FD_WORKER].fd = worker_watch[READ_END];
1194 rules = udev_rules_new(udev, resolve_names);
1195 if (rules == NULL) {
1196 err(udev, "error reading rules\n");
1200 udev_queue_export = udev_queue_export_new(udev);
1201 if (udev_queue_export == NULL) {
1202 err(udev, "error creating queue file\n");
1207 dup2(fd, STDIN_FILENO);
1208 dup2(fd, STDOUT_FILENO);
1209 dup2(fd, STDERR_FILENO);
1211 if (fd > STDERR_FILENO)
1222 err(udev, "fork of daemon failed: %m\n");
1230 sd_notify(1, "READY=1");
1233 /* set scheduling priority for the main daemon process */
1234 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
1238 f = fopen("/dev/kmsg", "w");
1240 fprintf(f, "<6>udev[%u]: starting version " VERSION "\n", getpid());
1244 fd = open("/proc/self/oom_score_adj", O_RDWR);
1246 /* Fallback to old interface */
1247 fd = open("/proc/self/oom_adj", O_RDWR);
1249 err(udev, "error disabling OOM: %m\n");
1251 /* OOM_DISABLE == -17 */
1252 write(fd, "-17", 3);
1256 write(fd, "-1000", 5);
1260 if (children_max <= 0) {
1261 int memsize = mem_size_mb();
1263 /* set value depending on the amount of RAM */
1265 children_max = 128 + (memsize / 8);
1269 info(udev, "set children_max to %u\n", children_max);
1271 udev_rules_apply_static_dev_perms(rules);
1273 udev_list_init(&event_list);
1274 udev_list_init(&worker_list);
1276 while (!udev_exit) {
1280 /* set timeout to kill idle workers */
1281 if (udev_list_is_empty(&event_list) && children > 2)
1285 /* wait for events */
1286 fdcount = poll(pfd, ARRAY_SIZE(pfd), timeout);
1290 /* timeout - kill idle workers */
1292 worker_kill(udev, 2);
1294 /* event has finished */
1295 if (pfd[FD_WORKER].revents & POLLIN)
1298 /* get kernel uevent */
1299 if (pfd[FD_NETLINK].revents & POLLIN) {
1300 struct udev_device *dev;
1302 dev = udev_monitor_receive_device(monitor);
1304 if (event_queue_insert(dev) < 0)
1305 udev_device_unref(dev);
1308 /* start new events */
1309 if (!udev_list_is_empty(&event_list) && !stop_exec_queue)
1313 if (pfd[FD_SIGNAL].revents & POLLIN) {
1314 struct signalfd_siginfo fdsi;
1317 size = read(pfd[FD_SIGNAL].fd, &fdsi, sizeof(struct signalfd_siginfo));
1318 if (size == sizeof(struct signalfd_siginfo))
1319 handle_signal(udev, fdsi.ssi_signo);
1322 /* device node and rules directory inotify watch */
1323 if (pfd[FD_INOTIFY].revents & POLLIN)
1324 handle_inotify(udev);
1327 * get control message
1329 * This needs to be after the inotify handling, to make sure,
1330 * that the settle signal is send back after the possibly generated
1331 * "change" events by the inotify device node watch.
1333 if (pfd[FD_CONTROL].revents & POLLIN)
1334 handle_ctrl_msg(udev_ctrl);
1336 /* rules changed, set by inotify or a HUP signal */
1337 if (reload_config) {
1338 struct udev_rules *rules_new;
1340 worker_kill(udev, 0);
1341 rules_new = udev_rules_new(udev, resolve_names);
1342 if (rules_new != NULL) {
1343 udev_rules_unref(rules);
1350 udev_queue_export_cleanup(udev_queue_export);
1353 udev_queue_export_unref(udev_queue_export);
1354 udev_rules_unref(rules);
1355 udev_ctrl_unref(udev_ctrl);
1356 if (pfd[FD_SIGNAL].fd >= 0)
1357 close(pfd[FD_SIGNAL].fd);
1358 if (worker_watch[READ_END] >= 0)
1359 close(worker_watch[READ_END]);
1360 if (worker_watch[WRITE_END] >= 0)
1361 close(worker_watch[WRITE_END]);
1362 udev_monitor_unref(monitor);
1363 udev_selinux_exit(udev);