2 * Copyright (C) 2004-2012 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
4 * Copyright (C) 2009 Canonical Ltd.
5 * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
35 #include <sys/prctl.h>
36 #include <sys/socket.h>
38 #include <sys/signalfd.h>
39 #include <sys/epoll.h>
43 #include <sys/ioctl.h>
44 #include <sys/inotify.h>
45 #include <sys/utsname.h>
48 #include "sd-daemon.h"
49 #include "cgroup-util.h"
50 #include "dev-setup.h"
54 void udev_main_log(struct udev
*udev
, int priority
,
55 const char *file
, int line
, const char *fn
,
56 const char *format
, va_list args
)
58 log_metav(priority
, file
, line
, fn
, format
, args
);
61 static struct udev_rules
*rules
;
62 static struct udev_queue_export
*udev_queue_export
;
63 static struct udev_ctrl
*udev_ctrl
;
64 static struct udev_monitor
*monitor
;
65 static int worker_watch
[2] = { -1, -1 };
66 static int fd_signal
= -1;
67 static int fd_ep
= -1;
68 static int fd_inotify
= -1;
69 static bool stop_exec_queue
;
72 static int children_max
;
73 static int exec_delay
;
74 static sigset_t sigmask_orig
;
75 static UDEV_LIST(event_list
);
76 static UDEV_LIST(worker_list
);
78 static bool udev_exit
;
87 struct udev_list_node node
;
89 struct udev_device
*dev
;
90 enum event_state state
;
92 unsigned long long int delaying_seqnum
;
93 unsigned long long int seqnum
;
96 const char *devpath_old
;
102 static inline struct event
*node_to_event(struct udev_list_node
*node
)
104 return container_of(node
, struct event
, node
);
107 static void event_queue_cleanup(struct udev
*udev
, enum event_state type
);
117 struct udev_list_node node
;
121 struct udev_monitor
*monitor
;
122 enum worker_state state
;
124 unsigned long long event_start_usec
;
127 /* passed from worker to main process */
128 struct worker_message
{
133 static inline struct worker
*node_to_worker(struct udev_list_node
*node
)
135 return container_of(node
, struct worker
, node
);
138 static void event_queue_delete(struct event
*event
, bool export
)
140 udev_list_node_remove(&event
->node
);
143 udev_queue_export_device_finished(udev_queue_export
, event
->dev
);
144 log_debug("seq %llu done with %i\n", udev_device_get_seqnum(event
->dev
), event
->exitcode
);
146 udev_device_unref(event
->dev
);
150 static struct worker
*worker_ref(struct worker
*worker
)
156 static void worker_cleanup(struct worker
*worker
)
158 udev_list_node_remove(&worker
->node
);
159 udev_monitor_unref(worker
->monitor
);
164 static void worker_unref(struct worker
*worker
)
167 if (worker
->refcount
> 0)
169 log_debug("worker [%u] cleaned up\n", worker
->pid
);
170 worker_cleanup(worker
);
173 static void worker_list_cleanup(struct udev
*udev
)
175 struct udev_list_node
*loop
, *tmp
;
177 udev_list_node_foreach_safe(loop
, tmp
, &worker_list
) {
178 struct worker
*worker
= node_to_worker(loop
);
180 worker_cleanup(worker
);
184 static void worker_new(struct event
*event
)
186 struct udev
*udev
= event
->udev
;
187 struct worker
*worker
;
188 struct udev_monitor
*worker_monitor
;
191 /* listen for new events */
192 worker_monitor
= udev_monitor_new_from_netlink(udev
, NULL
);
193 if (worker_monitor
== NULL
)
195 /* allow the main daemon netlink address to send devices to the worker */
196 udev_monitor_allow_unicast_sender(worker_monitor
, monitor
);
197 udev_monitor_enable_receiving(worker_monitor
);
199 worker
= calloc(1, sizeof(struct worker
));
200 if (worker
== NULL
) {
201 udev_monitor_unref(worker_monitor
);
204 /* worker + event reference */
205 worker
->refcount
= 2;
211 struct udev_device
*dev
= NULL
;
213 struct epoll_event ep_signal
, ep_monitor
;
215 int rc
= EXIT_SUCCESS
;
217 /* take initial device from queue */
222 worker_list_cleanup(udev
);
223 event_queue_cleanup(udev
, EVENT_UNDEF
);
224 udev_queue_export_unref(udev_queue_export
);
225 udev_monitor_unref(monitor
);
226 udev_ctrl_unref(udev_ctrl
);
229 close(worker_watch
[READ_END
]);
232 fd_signal
= signalfd(-1, &mask
, SFD_NONBLOCK
|SFD_CLOEXEC
);
234 log_error("error creating signalfd %m\n");
239 fd_ep
= epoll_create1(EPOLL_CLOEXEC
);
241 log_error("error creating epoll fd: %m\n");
246 memset(&ep_signal
, 0, sizeof(struct epoll_event
));
247 ep_signal
.events
= EPOLLIN
;
248 ep_signal
.data
.fd
= fd_signal
;
250 fd_monitor
= udev_monitor_get_fd(worker_monitor
);
251 memset(&ep_monitor
, 0, sizeof(struct epoll_event
));
252 ep_monitor
.events
= EPOLLIN
;
253 ep_monitor
.data
.fd
= fd_monitor
;
255 if (epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_signal
, &ep_signal
) < 0 ||
256 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_monitor
, &ep_monitor
) < 0) {
257 log_error("fail to add fds to epoll: %m\n");
262 /* request TERM signal if parent exits */
263 prctl(PR_SET_PDEATHSIG
, SIGTERM
);
265 /* reset OOM score, we only protect the main daemon */
266 write_one_line_file("/proc/self/oom_score_adj", "0");
269 struct udev_event
*udev_event
;
270 struct worker_message msg
;
273 log_debug("seq %llu running\n", udev_device_get_seqnum(dev
));
274 udev_event
= udev_event_new(dev
);
275 if (udev_event
== NULL
) {
280 /* needed for SIGCHLD/SIGTERM in spawn() */
281 udev_event
->fd_signal
= fd_signal
;
284 udev_event
->exec_delay
= exec_delay
;
286 /* apply rules, create node, symlinks */
287 err
= udev_event_execute_rules(udev_event
, rules
, &sigmask_orig
);
290 udev_event_execute_run(udev_event
, &sigmask_orig
);
292 /* apply/restore inotify watch */
293 if (err
== 0 && udev_event
->inotify_watch
) {
294 udev_watch_begin(udev
, dev
);
295 udev_device_update_db(dev
);
298 /* send processed event back to libudev listeners */
299 udev_monitor_send_device(worker_monitor
, NULL
, dev
);
301 /* send udevd the result of the event execution */
302 memset(&msg
, 0, sizeof(struct worker_message
));
306 send(worker_watch
[WRITE_END
], &msg
, sizeof(struct worker_message
), 0);
308 log_debug("seq %llu processed with %i\n", udev_device_get_seqnum(dev
), err
);
310 udev_device_unref(dev
);
313 if (udev_event
->sigterm
) {
314 udev_event_unref(udev_event
);
318 udev_event_unref(udev_event
);
320 /* wait for more device messages from main udevd, or term signal */
321 while (dev
== NULL
) {
322 struct epoll_event ev
[4];
326 fdcount
= epoll_wait(fd_ep
, ev
, ELEMENTSOF(ev
), -1);
330 log_error("failed to poll: %m\n");
334 for (i
= 0; i
< fdcount
; i
++) {
335 if (ev
[i
].data
.fd
== fd_monitor
&& ev
[i
].events
& EPOLLIN
) {
336 dev
= udev_monitor_receive_device(worker_monitor
);
338 } else if (ev
[i
].data
.fd
== fd_signal
&& ev
[i
].events
& EPOLLIN
) {
339 struct signalfd_siginfo fdsi
;
342 size
= read(fd_signal
, &fdsi
, sizeof(struct signalfd_siginfo
));
343 if (size
!= sizeof(struct signalfd_siginfo
))
345 switch (fdsi
.ssi_signo
) {
354 udev_device_unref(dev
);
360 close(worker_watch
[WRITE_END
]);
361 udev_rules_unref(rules
);
362 udev_builtin_exit(udev
);
363 udev_monitor_unref(worker_monitor
);
369 udev_monitor_unref(worker_monitor
);
370 event
->state
= EVENT_QUEUED
;
372 log_error("fork of child failed: %m\n");
375 /* close monitor, but keep address around */
376 udev_monitor_disconnect(worker_monitor
);
377 worker
->monitor
= worker_monitor
;
379 worker
->state
= WORKER_RUNNING
;
380 worker
->event_start_usec
= now_usec();
381 worker
->event
= event
;
382 event
->state
= EVENT_RUNNING
;
383 udev_list_node_append(&worker
->node
, &worker_list
);
385 log_debug("seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event
->dev
), pid
);
390 static void event_run(struct event
*event
)
392 struct udev_list_node
*loop
;
394 udev_list_node_foreach(loop
, &worker_list
) {
395 struct worker
*worker
= node_to_worker(loop
);
398 if (worker
->state
!= WORKER_IDLE
)
401 count
= udev_monitor_send_device(monitor
, worker
->monitor
, event
->dev
);
403 log_error("worker [%u] did not accept message %zi (%m), kill it\n", worker
->pid
, count
);
404 kill(worker
->pid
, SIGKILL
);
405 worker
->state
= WORKER_KILLED
;
409 worker
->event
= event
;
410 worker
->state
= WORKER_RUNNING
;
411 worker
->event_start_usec
= now_usec();
412 event
->state
= EVENT_RUNNING
;
416 if (children
>= children_max
) {
417 if (children_max
> 1)
418 log_debug("maximum number (%i) of children reached\n", children
);
422 /* start new worker and pass initial device */
426 static int event_queue_insert(struct udev_device
*dev
)
430 event
= calloc(1, sizeof(struct event
));
434 event
->udev
= udev_device_get_udev(dev
);
436 event
->seqnum
= udev_device_get_seqnum(dev
);
437 event
->devpath
= udev_device_get_devpath(dev
);
438 event
->devpath_len
= strlen(event
->devpath
);
439 event
->devpath_old
= udev_device_get_devpath_old(dev
);
440 event
->devnum
= udev_device_get_devnum(dev
);
441 event
->is_block
= (strcmp("block", udev_device_get_subsystem(dev
)) == 0);
442 event
->ifindex
= udev_device_get_ifindex(dev
);
444 udev_queue_export_device_queued(udev_queue_export
, dev
);
445 log_debug("seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev
),
446 udev_device_get_action(dev
), udev_device_get_subsystem(dev
));
448 event
->state
= EVENT_QUEUED
;
449 udev_list_node_append(&event
->node
, &event_list
);
453 static void worker_kill(struct udev
*udev
)
455 struct udev_list_node
*loop
;
457 udev_list_node_foreach(loop
, &worker_list
) {
458 struct worker
*worker
= node_to_worker(loop
);
460 if (worker
->state
== WORKER_KILLED
)
463 worker
->state
= WORKER_KILLED
;
464 kill(worker
->pid
, SIGTERM
);
468 /* lookup event for identical, parent, child device */
469 static bool is_devpath_busy(struct event
*event
)
471 struct udev_list_node
*loop
;
474 /* check if queue contains events we depend on */
475 udev_list_node_foreach(loop
, &event_list
) {
476 struct event
*loop_event
= node_to_event(loop
);
478 /* we already found a later event, earlier can not block us, no need to check again */
479 if (loop_event
->seqnum
< event
->delaying_seqnum
)
482 /* event we checked earlier still exists, no need to check again */
483 if (loop_event
->seqnum
== event
->delaying_seqnum
)
486 /* found ourself, no later event can block us */
487 if (loop_event
->seqnum
>= event
->seqnum
)
490 /* check major/minor */
491 if (major(event
->devnum
) != 0 && event
->devnum
== loop_event
->devnum
&& event
->is_block
== loop_event
->is_block
)
494 /* check network device ifindex */
495 if (event
->ifindex
!= 0 && event
->ifindex
== loop_event
->ifindex
)
498 /* check our old name */
499 if (event
->devpath_old
!= NULL
&& strcmp(loop_event
->devpath
, event
->devpath_old
) == 0) {
500 event
->delaying_seqnum
= loop_event
->seqnum
;
504 /* compare devpath */
505 common
= MIN(loop_event
->devpath_len
, event
->devpath_len
);
507 /* one devpath is contained in the other? */
508 if (memcmp(loop_event
->devpath
, event
->devpath
, common
) != 0)
511 /* identical device event found */
512 if (loop_event
->devpath_len
== event
->devpath_len
) {
513 /* devices names might have changed/swapped in the meantime */
514 if (major(event
->devnum
) != 0 && (event
->devnum
!= loop_event
->devnum
|| event
->is_block
!= loop_event
->is_block
))
516 if (event
->ifindex
!= 0 && event
->ifindex
!= loop_event
->ifindex
)
518 event
->delaying_seqnum
= loop_event
->seqnum
;
522 /* parent device event found */
523 if (event
->devpath
[common
] == '/') {
524 event
->delaying_seqnum
= loop_event
->seqnum
;
528 /* child device event found */
529 if (loop_event
->devpath
[common
] == '/') {
530 event
->delaying_seqnum
= loop_event
->seqnum
;
534 /* no matching device */
541 static void event_queue_start(struct udev
*udev
)
543 struct udev_list_node
*loop
;
545 udev_list_node_foreach(loop
, &event_list
) {
546 struct event
*event
= node_to_event(loop
);
548 if (event
->state
!= EVENT_QUEUED
)
551 /* do not start event if parent or child event is still running */
552 if (is_devpath_busy(event
))
559 static void event_queue_cleanup(struct udev
*udev
, enum event_state match_type
)
561 struct udev_list_node
*loop
, *tmp
;
563 udev_list_node_foreach_safe(loop
, tmp
, &event_list
) {
564 struct event
*event
= node_to_event(loop
);
566 if (match_type
!= EVENT_UNDEF
&& match_type
!= event
->state
)
569 event_queue_delete(event
, false);
573 static void worker_returned(int fd_worker
)
576 struct worker_message msg
;
578 struct udev_list_node
*loop
;
580 size
= recv(fd_worker
, &msg
, sizeof(struct worker_message
), MSG_DONTWAIT
);
581 if (size
!= sizeof(struct worker_message
))
584 /* lookup worker who sent the signal */
585 udev_list_node_foreach(loop
, &worker_list
) {
586 struct worker
*worker
= node_to_worker(loop
);
588 if (worker
->pid
!= msg
.pid
)
591 /* worker returned */
593 worker
->event
->exitcode
= msg
.exitcode
;
594 event_queue_delete(worker
->event
, true);
595 worker
->event
= NULL
;
597 if (worker
->state
!= WORKER_KILLED
)
598 worker
->state
= WORKER_IDLE
;
599 worker_unref(worker
);
605 /* receive the udevd message from userspace */
606 static struct udev_ctrl_connection
*handle_ctrl_msg(struct udev_ctrl
*uctrl
)
608 struct udev
*udev
= udev_ctrl_get_udev(uctrl
);
609 struct udev_ctrl_connection
*ctrl_conn
;
610 struct udev_ctrl_msg
*ctrl_msg
= NULL
;
614 ctrl_conn
= udev_ctrl_get_connection(uctrl
);
615 if (ctrl_conn
== NULL
)
618 ctrl_msg
= udev_ctrl_receive_msg(ctrl_conn
);
619 if (ctrl_msg
== NULL
)
622 i
= udev_ctrl_get_set_log_level(ctrl_msg
);
624 log_debug("udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i
);
625 log_set_max_level(i
);
626 udev_set_log_priority(udev
, i
);
630 if (udev_ctrl_get_stop_exec_queue(ctrl_msg
) > 0) {
631 log_debug("udevd message (STOP_EXEC_QUEUE) received\n");
632 stop_exec_queue
= true;
635 if (udev_ctrl_get_start_exec_queue(ctrl_msg
) > 0) {
636 log_debug("udevd message (START_EXEC_QUEUE) received\n");
637 stop_exec_queue
= false;
640 if (udev_ctrl_get_reload(ctrl_msg
) > 0) {
641 log_debug("udevd message (RELOAD) received\n");
645 str
= udev_ctrl_get_set_env(ctrl_msg
);
653 val
= strchr(key
, '=');
657 if (val
[0] == '\0') {
658 log_debug("udevd message (ENV) received, unset '%s'\n", key
);
659 udev_add_property(udev
, key
, NULL
);
661 log_debug("udevd message (ENV) received, set '%s=%s'\n", key
, val
);
662 udev_add_property(udev
, key
, val
);
665 log_error("wrong key format '%s'\n", key
);
672 i
= udev_ctrl_get_set_children_max(ctrl_msg
);
674 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i\n", i
);
678 if (udev_ctrl_get_ping(ctrl_msg
) > 0)
679 log_debug("udevd message (SYNC) received\n");
681 if (udev_ctrl_get_exit(ctrl_msg
) > 0) {
682 log_debug("udevd message (EXIT) received\n");
684 /* keep reference to block the client until we exit */
685 udev_ctrl_connection_ref(ctrl_conn
);
688 udev_ctrl_msg_unref(ctrl_msg
);
689 return udev_ctrl_connection_unref(ctrl_conn
);
692 /* read inotify messages */
693 static int handle_inotify(struct udev
*udev
)
697 struct inotify_event
*ev
;
699 if ((ioctl(fd_inotify
, FIONREAD
, &nbytes
) < 0) || (nbytes
<= 0))
702 buf
= malloc(nbytes
);
704 log_error("error getting buffer for inotify\n");
708 nbytes
= read(fd_inotify
, buf
, nbytes
);
710 for (pos
= 0; pos
< nbytes
; pos
+= sizeof(struct inotify_event
) + ev
->len
) {
711 struct udev_device
*dev
;
713 ev
= (struct inotify_event
*)(buf
+ pos
);
714 dev
= udev_watch_lookup(udev
, ev
->wd
);
716 log_debug("inotify event: %x for %s\n", ev
->mask
, udev_device_get_devnode(dev
));
717 if (ev
->mask
& IN_CLOSE_WRITE
) {
718 char filename
[UTIL_PATH_SIZE
];
721 log_debug("device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev
));
722 util_strscpyl(filename
, sizeof(filename
), udev_device_get_syspath(dev
), "/uevent", NULL
);
723 fd
= open(filename
, O_WRONLY
);
725 if (write(fd
, "change", 6) < 0)
726 log_debug("error writing uevent: %m\n");
730 if (ev
->mask
& IN_IGNORED
)
731 udev_watch_end(udev
, dev
);
733 udev_device_unref(dev
);
742 static void handle_signal(struct udev
*udev
, int signo
)
753 struct udev_list_node
*loop
, *tmp
;
755 pid
= waitpid(-1, &status
, WNOHANG
);
759 udev_list_node_foreach_safe(loop
, tmp
, &worker_list
) {
760 struct worker
*worker
= node_to_worker(loop
);
762 if (worker
->pid
!= pid
)
764 log_debug("worker [%u] exit\n", pid
);
766 if (WIFEXITED(status
)) {
767 if (WEXITSTATUS(status
) != 0)
768 log_error("worker [%u] exit with return code %i\n", pid
, WEXITSTATUS(status
));
769 } else if (WIFSIGNALED(status
)) {
770 log_error("worker [%u] terminated by signal %i (%s)\n",
771 pid
, WTERMSIG(status
), strsignal(WTERMSIG(status
)));
772 } else if (WIFSTOPPED(status
)) {
773 log_error("worker [%u] stopped\n", pid
);
774 } else if (WIFCONTINUED(status
)) {
775 log_error("worker [%u] continued\n", pid
);
777 log_error("worker [%u] exit with status 0x%04x\n", pid
, status
);
780 if (!WIFEXITED(status
) || WEXITSTATUS(status
) != 0) {
782 log_error("worker [%u] failed while handling '%s'\n",
783 pid
, worker
->event
->devpath
);
784 worker
->event
->exitcode
= -32;
785 event_queue_delete(worker
->event
, true);
786 /* drop reference taken for state 'running' */
787 worker_unref(worker
);
790 worker_unref(worker
);
801 static void static_dev_create_from_modules(struct udev
*udev
)
803 struct utsname kernel
;
804 char modules
[UTIL_PATH_SIZE
];
809 util_strscpyl(modules
, sizeof(modules
), ROOTPREFIX
"/lib/modules/", kernel
.release
, "/modules.devname", NULL
);
810 f
= fopen(modules
, "re");
814 while (fgets(buf
, sizeof(buf
), f
) != NULL
) {
822 char filename
[UTIL_PATH_SIZE
];
828 s
= strchr(modname
, ' ');
834 s
= strchr(devname
, ' ');
840 s
= strchr(devno
, ' ');
842 s
= strchr(devno
, '\n');
845 if (sscanf(devno
, "%c%u:%u", &type
, &maj
, &min
) != 3)
851 else if (type
== 'b')
856 util_strscpyl(filename
, sizeof(filename
), "/dev/", devname
, NULL
);
857 mkdir_parents_label(filename
, 0755);
858 label_context_set(filename
, mode
);
859 log_debug("mknod '%s' %c%u:%u\n", filename
, type
, maj
, min
);
860 if (mknod(filename
, mode
, makedev(maj
, min
)) < 0 && errno
== EEXIST
)
861 utimensat(AT_FDCWD
, filename
, NULL
, 0);
862 label_context_clear();
868 static int mem_size_mb(void)
872 long int memsize
= -1;
874 f
= fopen("/proc/meminfo", "re");
878 while (fgets(buf
, sizeof(buf
), f
) != NULL
) {
881 if (sscanf(buf
, "MemTotal: %ld kB", &value
) == 1) {
882 memsize
= value
/ 1024;
891 static int convert_db(struct udev
*udev
)
893 char filename
[UTIL_PATH_SIZE
];
894 struct udev_enumerate
*udev_enumerate
;
895 struct udev_list_entry
*list_entry
;
897 /* current database */
898 if (access("/run/udev/data", F_OK
) >= 0)
901 /* make sure we do not get here again */
902 mkdir_p("/run/udev/data", 0755);
905 util_strscpyl(filename
, sizeof(filename
), "/dev/.udev/db", NULL
);
906 if (access(filename
, F_OK
) < 0)
909 print_kmsg("converting old udev database\n");
911 udev_enumerate
= udev_enumerate_new(udev
);
912 if (udev_enumerate
== NULL
)
914 udev_enumerate_scan_devices(udev_enumerate
);
915 udev_list_entry_foreach(list_entry
, udev_enumerate_get_list_entry(udev_enumerate
)) {
916 struct udev_device
*device
;
918 device
= udev_device_new_from_syspath(udev
, udev_list_entry_get_name(list_entry
));
922 /* try to find the old database for devices without a current one */
923 if (udev_device_read_db(device
, NULL
) < 0) {
927 char devpath
[UTIL_PATH_SIZE
];
928 char from
[UTIL_PATH_SIZE
];
932 /* find database in old location */
933 id
= udev_device_get_id_filename(device
);
934 util_strscpyl(from
, sizeof(from
), "/dev/.udev/db/", id
, NULL
);
935 if (lstat(from
, &stats
) == 0) {
937 udev_device_read_db(device
, from
);
943 /* find old database with $subsys:$sysname name */
944 util_strscpyl(from
, sizeof(from
), "/dev/.udev/db/",
945 udev_device_get_subsystem(device
), ":", udev_device_get_sysname(device
), NULL
);
946 if (lstat(from
, &stats
) == 0) {
948 udev_device_read_db(device
, from
);
954 /* find old database with the encoded devpath name */
955 util_path_encode(udev_device_get_devpath(device
), devpath
, sizeof(devpath
));
956 util_strscpyl(from
, sizeof(from
), "/dev/.udev/db/", devpath
, NULL
);
957 if (lstat(from
, &stats
) == 0) {
959 udev_device_read_db(device
, from
);
965 /* write out new database */
967 udev_device_update_db(device
);
969 udev_device_unref(device
);
971 udev_enumerate_unref(udev_enumerate
);
975 static int systemd_fds(struct udev
*udev
, int *rctrl
, int *rnetlink
)
977 int ctrl
= -1, netlink
= -1;
980 n
= sd_listen_fds(true);
984 for (fd
= SD_LISTEN_FDS_START
; fd
< n
+ SD_LISTEN_FDS_START
; fd
++) {
985 if (sd_is_socket(fd
, AF_LOCAL
, SOCK_SEQPACKET
, -1)) {
992 if (sd_is_socket(fd
, AF_NETLINK
, SOCK_RAW
, -1)) {
1002 if (ctrl
< 0 || netlink
< 0)
1005 log_debug("ctrl=%i netlink=%i\n", ctrl
, netlink
);
1007 *rnetlink
= netlink
;
1012 * read the kernel commandline, in case we need to get into debug mode
1013 * udev.log-priority=<level> syslog priority
1014 * udev.children-max=<number of workers> events are fully serialized if set to 1
1015 * udev.exec-delay=<number of seconds> delay execution of every executed program
1017 static void kernel_cmdline_options(struct udev
*udev
)
1019 char *line
, *w
, *state
;
1022 if (read_one_line_file("/proc/cmdline", &line
) < 0)
1025 FOREACH_WORD_QUOTED(w
, l
, line
, state
) {
1032 /* accept the same options for the initrd, prefixed with "rd." */
1033 if (in_initrd() && startswith(s
, "rd."))
1038 if (startswith(opt
, "udev.log-priority=")) {
1041 prio
= util_log_priority(opt
+ 18);
1042 log_set_max_level(prio
);
1043 udev_set_log_priority(udev
, prio
);
1044 } else if (startswith(opt
, "udev.children-max=")) {
1045 children_max
= strtoul(opt
+ 18, NULL
, 0);
1046 } else if (startswith(opt
, "udev.exec-delay=")) {
1047 exec_delay
= strtoul(opt
+ 16, NULL
, 0);
1056 int main(int argc
, char *argv
[])
1060 int daemonize
= false;
1061 int resolve_names
= 1;
1062 static const struct option options
[] = {
1063 { "daemon", no_argument
, NULL
, 'd' },
1064 { "debug", no_argument
, NULL
, 'D' },
1065 { "children-max", required_argument
, NULL
, 'c' },
1066 { "exec-delay", required_argument
, NULL
, 'e' },
1067 { "resolve-names", required_argument
, NULL
, 'N' },
1068 { "help", no_argument
, NULL
, 'h' },
1069 { "version", no_argument
, NULL
, 'V' },
1073 int fd_netlink
= -1;
1075 struct epoll_event ep_ctrl
, ep_inotify
, ep_signal
, ep_netlink
, ep_worker
;
1076 struct udev_ctrl_connection
*ctrl_conn
= NULL
;
1083 log_set_target(LOG_TARGET_AUTO
);
1084 log_parse_environment();
1086 udev_set_log_fn(udev
, udev_main_log
);
1087 log_debug("version %s\n", VERSION
);
1093 option
= getopt_long(argc
, argv
, "c:deDtN:hV", options
, NULL
);
1102 children_max
= strtoul(optarg
, NULL
, 0);
1105 exec_delay
= strtoul(optarg
, NULL
, 0);
1109 log_set_max_level(LOG_DEBUG
);
1110 udev_set_log_priority(udev
, LOG_DEBUG
);
1113 if (strcmp (optarg
, "early") == 0) {
1115 } else if (strcmp (optarg
, "late") == 0) {
1117 } else if (strcmp (optarg
, "never") == 0) {
1120 fprintf(stderr
, "resolve-names must be early, late or never\n");
1121 log_error("resolve-names must be early, late or never\n");
1126 printf("Usage: udevd OPTIONS\n"
1129 " --children-max=<maximum number of workers>\n"
1130 " --exec-delay=<seconds to wait before executing RUN=>\n"
1131 " --resolve-names=early|late|never\n"
1137 printf("%s\n", VERSION
);
1144 kernel_cmdline_options(udev
);
1146 if (getuid() != 0) {
1147 fprintf(stderr
, "root privileges required\n");
1148 log_error("root privileges required\n");
1152 /* set umask before creating any file/directory */
1156 mkdir("/run/udev", 0755);
1159 static_dev_create_from_modules(udev
);
1161 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1165 fd
= open("/dev/null", O_RDWR
);
1167 if (write(STDOUT_FILENO
, 0, 0) < 0)
1168 dup2(fd
, STDOUT_FILENO
);
1169 if (write(STDERR_FILENO
, 0, 0) < 0)
1170 dup2(fd
, STDERR_FILENO
);
1171 if (fd
> STDERR_FILENO
)
1174 fprintf(stderr
, "cannot open /dev/null\n");
1175 log_error("cannot open /dev/null\n");
1179 if (systemd_fds(udev
, &fd_ctrl
, &fd_netlink
) >= 0) {
1180 /* get control and netlink socket from from systemd */
1181 udev_ctrl
= udev_ctrl_new_from_fd(udev
, fd_ctrl
);
1182 if (udev_ctrl
== NULL
) {
1183 log_error("error taking over udev control socket");
1188 monitor
= udev_monitor_new_from_netlink_fd(udev
, "kernel", fd_netlink
);
1189 if (monitor
== NULL
) {
1190 log_error("error taking over netlink socket\n");
1195 /* get our own cgroup, we regularly kill everything udev has left behind */
1196 if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER
, 0, &udev_cgroup
) < 0)
1199 /* open control and netlink socket */
1200 udev_ctrl
= udev_ctrl_new(udev
);
1201 if (udev_ctrl
== NULL
) {
1202 fprintf(stderr
, "error initializing udev control socket");
1203 log_error("error initializing udev control socket");
1207 fd_ctrl
= udev_ctrl_get_fd(udev_ctrl
);
1209 monitor
= udev_monitor_new_from_netlink(udev
, "kernel");
1210 if (monitor
== NULL
) {
1211 fprintf(stderr
, "error initializing netlink socket\n");
1212 log_error("error initializing netlink socket\n");
1216 fd_netlink
= udev_monitor_get_fd(monitor
);
1219 if (udev_monitor_enable_receiving(monitor
) < 0) {
1220 fprintf(stderr
, "error binding netlink socket\n");
1221 log_error("error binding netlink socket\n");
1226 if (udev_ctrl_enable_receiving(udev_ctrl
) < 0) {
1227 fprintf(stderr
, "error binding udev control socket\n");
1228 log_error("error binding udev control socket\n");
1233 udev_monitor_set_receive_buffer_size(monitor
, 128*1024*1024);
1235 /* create queue file before signalling 'ready', to make sure we block 'settle' */
1236 udev_queue_export
= udev_queue_export_new(udev
);
1237 if (udev_queue_export
== NULL
) {
1238 log_error("error creating queue file\n");
1250 log_error("fork of daemon failed: %m\n");
1255 goto exit_daemonize
;
1260 write_one_line_file("/proc/self/oom_score_adj", "-1000");
1262 sd_notify(1, "READY=1");
1265 print_kmsg("starting version " VERSION
"\n");
1270 fd
= open("/dev/null", O_RDWR
);
1272 dup2(fd
, STDIN_FILENO
);
1273 dup2(fd
, STDOUT_FILENO
);
1274 dup2(fd
, STDERR_FILENO
);
1279 fd_inotify
= udev_watch_init(udev
);
1280 if (fd_inotify
< 0) {
1281 fprintf(stderr
, "error initializing inotify\n");
1282 log_error("error initializing inotify\n");
1286 udev_watch_restore(udev
);
1288 /* block and listen to all signals on signalfd */
1290 sigprocmask(SIG_SETMASK
, &mask
, &sigmask_orig
);
1291 fd_signal
= signalfd(-1, &mask
, SFD_NONBLOCK
|SFD_CLOEXEC
);
1292 if (fd_signal
< 0) {
1293 fprintf(stderr
, "error creating signalfd\n");
1294 log_error("error creating signalfd\n");
1299 /* unnamed socket from workers to the main daemon */
1300 if (socketpair(AF_LOCAL
, SOCK_DGRAM
|SOCK_CLOEXEC
, 0, worker_watch
) < 0) {
1301 fprintf(stderr
, "error creating socketpair\n");
1302 log_error("error creating socketpair\n");
1306 fd_worker
= worker_watch
[READ_END
];
1308 udev_builtin_init(udev
);
1310 rules
= udev_rules_new(udev
, resolve_names
);
1311 if (rules
== NULL
) {
1312 log_error("error reading rules\n");
1316 memset(&ep_ctrl
, 0, sizeof(struct epoll_event
));
1317 ep_ctrl
.events
= EPOLLIN
;
1318 ep_ctrl
.data
.fd
= fd_ctrl
;
1320 memset(&ep_inotify
, 0, sizeof(struct epoll_event
));
1321 ep_inotify
.events
= EPOLLIN
;
1322 ep_inotify
.data
.fd
= fd_inotify
;
1324 memset(&ep_signal
, 0, sizeof(struct epoll_event
));
1325 ep_signal
.events
= EPOLLIN
;
1326 ep_signal
.data
.fd
= fd_signal
;
1328 memset(&ep_netlink
, 0, sizeof(struct epoll_event
));
1329 ep_netlink
.events
= EPOLLIN
;
1330 ep_netlink
.data
.fd
= fd_netlink
;
1332 memset(&ep_worker
, 0, sizeof(struct epoll_event
));
1333 ep_worker
.events
= EPOLLIN
;
1334 ep_worker
.data
.fd
= fd_worker
;
1336 fd_ep
= epoll_create1(EPOLL_CLOEXEC
);
1338 log_error("error creating epoll fd: %m\n");
1341 if (epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_ctrl
, &ep_ctrl
) < 0 ||
1342 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_inotify
, &ep_inotify
) < 0 ||
1343 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_signal
, &ep_signal
) < 0 ||
1344 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_netlink
, &ep_netlink
) < 0 ||
1345 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_worker
, &ep_worker
) < 0) {
1346 log_error("fail to add fds to epoll: %m\n");
1350 /* if needed, convert old database from earlier udev version */
1353 if (children_max
<= 0) {
1354 int memsize
= mem_size_mb();
1356 /* set value depending on the amount of RAM */
1358 children_max
= 16 + (memsize
/ 8);
1362 log_debug("set children_max to %u\n", children_max
);
1364 udev_rules_apply_static_dev_perms(rules
);
1366 udev_list_node_init(&event_list
);
1367 udev_list_node_init(&worker_list
);
1370 static unsigned long long last_usec
;
1371 struct epoll_event ev
[8];
1374 bool is_worker
, is_signal
, is_inotify
, is_netlink
, is_ctrl
;
1378 /* close sources of new events and discard buffered events */
1380 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_ctrl
, NULL
);
1383 if (monitor
!= NULL
) {
1384 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_netlink
, NULL
);
1385 udev_monitor_unref(monitor
);
1388 if (fd_inotify
>= 0) {
1389 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_inotify
, NULL
);
1394 /* discard queued events and kill workers */
1395 event_queue_cleanup(udev
, EVENT_QUEUED
);
1398 /* exit after all has cleaned up */
1399 if (udev_list_node_is_empty(&event_list
) && udev_list_node_is_empty(&worker_list
))
1402 /* timeout at exit for workers to finish */
1403 timeout
= 30 * 1000;
1404 } else if (udev_list_node_is_empty(&event_list
) && !children
) {
1408 /* cleanup possible left-over processes in our cgroup */
1410 cg_kill(SYSTEMD_CGROUP_CONTROLLER
, udev_cgroup
, SIGKILL
, false, true, NULL
);
1412 /* kill idle or hanging workers */
1415 fdcount
= epoll_wait(fd_ep
, ev
, ELEMENTSOF(ev
), timeout
);
1420 struct udev_list_node
*loop
;
1424 log_error("timeout, giving up waiting for workers to finish\n");
1428 /* kill idle workers */
1429 if (udev_list_node_is_empty(&event_list
)) {
1430 log_debug("cleanup idle workers\n");
1434 /* check for hanging events */
1435 udev_list_node_foreach(loop
, &worker_list
) {
1436 struct worker
*worker
= node_to_worker(loop
);
1438 if (worker
->state
!= WORKER_RUNNING
)
1441 if ((now_usec() - worker
->event_start_usec
) > 30 * 1000 * 1000) {
1442 log_error("worker [%u] %s timeout; kill it\n", worker
->pid
,
1443 worker
->event
? worker
->event
->devpath
: "<idle>");
1444 kill(worker
->pid
, SIGKILL
);
1445 worker
->state
= WORKER_KILLED
;
1446 /* drop reference taken for state 'running' */
1447 worker_unref(worker
);
1448 if (worker
->event
) {
1449 log_error("seq %llu '%s' killed\n",
1450 udev_device_get_seqnum(worker
->event
->dev
), worker
->event
->devpath
);
1451 worker
->event
->exitcode
= -64;
1452 event_queue_delete(worker
->event
, true);
1453 worker
->event
= NULL
;
1460 is_worker
= is_signal
= is_inotify
= is_netlink
= is_ctrl
= false;
1461 for (i
= 0; i
< fdcount
; i
++) {
1462 if (ev
[i
].data
.fd
== fd_worker
&& ev
[i
].events
& EPOLLIN
)
1464 else if (ev
[i
].data
.fd
== fd_netlink
&& ev
[i
].events
& EPOLLIN
)
1466 else if (ev
[i
].data
.fd
== fd_signal
&& ev
[i
].events
& EPOLLIN
)
1468 else if (ev
[i
].data
.fd
== fd_inotify
&& ev
[i
].events
& EPOLLIN
)
1470 else if (ev
[i
].data
.fd
== fd_ctrl
&& ev
[i
].events
& EPOLLIN
)
1474 /* check for changed config, every 3 seconds at most */
1475 if ((now_usec() - last_usec
) > 3 * 1000 * 1000) {
1476 if (udev_rules_check_timestamp(rules
))
1478 if (udev_builtin_validate(udev
))
1481 last_usec
= now_usec();
1484 /* reload requested, HUP signal received, rules changed, builtin changed */
1487 rules
= udev_rules_unref(rules
);
1488 udev_builtin_exit(udev
);
1492 /* event has finished */
1494 worker_returned(fd_worker
);
1497 struct udev_device
*dev
;
1499 dev
= udev_monitor_receive_device(monitor
);
1501 udev_device_set_usec_initialized(dev
, now_usec());
1502 if (event_queue_insert(dev
) < 0)
1503 udev_device_unref(dev
);
1507 /* start new events */
1508 if (!udev_list_node_is_empty(&event_list
) && !udev_exit
&& !stop_exec_queue
) {
1509 udev_builtin_init(udev
);
1511 rules
= udev_rules_new(udev
, resolve_names
);
1513 event_queue_start(udev
);
1517 struct signalfd_siginfo fdsi
;
1520 size
= read(fd_signal
, &fdsi
, sizeof(struct signalfd_siginfo
));
1521 if (size
== sizeof(struct signalfd_siginfo
))
1522 handle_signal(udev
, fdsi
.ssi_signo
);
1525 /* we are shutting down, the events below are not handled anymore */
1529 /* device node watch */
1531 handle_inotify(udev
);
1534 * This needs to be after the inotify handling, to make sure,
1535 * that the ping is send back after the possibly generated
1536 * "change" events by the inotify device node watch.
1538 * A single time we may receive a client connection which we need to
1539 * keep open to block the client. It will be closed right before we
1543 ctrl_conn
= handle_ctrl_msg(udev_ctrl
);
1548 udev_queue_export_cleanup(udev_queue_export
);
1549 udev_ctrl_cleanup(udev_ctrl
);
1553 worker_list_cleanup(udev
);
1554 event_queue_cleanup(udev
, EVENT_UNDEF
);
1555 udev_rules_unref(rules
);
1556 udev_builtin_exit(udev
);
1559 if (worker_watch
[READ_END
] >= 0)
1560 close(worker_watch
[READ_END
]);
1561 if (worker_watch
[WRITE_END
] >= 0)
1562 close(worker_watch
[WRITE_END
]);
1563 udev_monitor_unref(monitor
);
1564 udev_queue_export_unref(udev_queue_export
);
1565 udev_ctrl_connection_unref(ctrl_conn
);
1566 udev_ctrl_unref(udev_ctrl
);