2 * Copyright (C) 2004-2012 Kay Sievers <kay@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/>.
36 #include <sys/prctl.h>
37 #include <sys/socket.h>
39 #include <sys/signalfd.h>
40 #include <sys/epoll.h>
41 #include <sys/mount.h>
45 #include <sys/ioctl.h>
46 #include <sys/inotify.h>
47 #include <sys/utsname.h>
50 #include "udev-util.h"
51 #include "rtnl-util.h"
52 #include "sd-daemon.h"
53 #include "cgroup-util.h"
54 #include "dev-setup.h"
57 static struct udev_rules
*rules
;
58 static struct udev_ctrl
*udev_ctrl
;
59 static struct udev_monitor
*monitor
;
60 static int worker_watch
[2] = { -1, -1 };
61 static int fd_signal
= -1;
62 static int fd_ep
= -1;
63 static int fd_inotify
= -1;
64 static bool stop_exec_queue
;
67 static bool arg_debug
= false;
68 static int arg_daemonize
= false;
69 static int arg_resolve_names
= 1;
70 static int arg_children_max
;
71 static int arg_exec_delay
;
72 static usec_t arg_event_timeout_usec
= 180 * USEC_PER_SEC
;
73 static usec_t arg_event_timeout_warn_usec
= 180 * USEC_PER_SEC
/ 3;
74 static sigset_t sigmask_orig
;
75 static UDEV_LIST(event_list
);
76 static UDEV_LIST(worker_list
);
77 static char *udev_cgroup
;
78 static struct udev_list properties_list
;
79 static bool udev_exit
;
88 struct udev_list_node node
;
90 struct udev_device
*dev
;
91 enum event_state state
;
93 unsigned long long int delaying_seqnum
;
94 unsigned long long int seqnum
;
97 const char *devpath_old
;
103 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 usec_t event_start_usec
;
128 /* passed from worker to main process */
129 struct worker_message
{
134 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
) {
139 udev_list_node_remove(&event
->node
);
140 udev_device_unref(event
->dev
);
144 static struct worker
*worker_ref(struct worker
*worker
) {
149 static void worker_cleanup(struct worker
*worker
) {
150 udev_list_node_remove(&worker
->node
);
151 udev_monitor_unref(worker
->monitor
);
156 static void worker_unref(struct worker
*worker
) {
158 if (worker
->refcount
> 0)
160 log_debug("worker [%u] cleaned up", worker
->pid
);
161 worker_cleanup(worker
);
164 static void worker_list_cleanup(struct udev
*udev
) {
165 struct udev_list_node
*loop
, *tmp
;
167 udev_list_node_foreach_safe(loop
, tmp
, &worker_list
) {
168 struct worker
*worker
= node_to_worker(loop
);
170 worker_cleanup(worker
);
174 static void worker_new(struct event
*event
) {
175 struct udev
*udev
= event
->udev
;
176 struct worker
*worker
;
177 struct udev_monitor
*worker_monitor
;
180 /* listen for new events */
181 worker_monitor
= udev_monitor_new_from_netlink(udev
, NULL
);
182 if (worker_monitor
== NULL
)
184 /* allow the main daemon netlink address to send devices to the worker */
185 udev_monitor_allow_unicast_sender(worker_monitor
, monitor
);
186 udev_monitor_enable_receiving(worker_monitor
);
188 worker
= new0(struct worker
, 1);
189 if (worker
== NULL
) {
190 udev_monitor_unref(worker_monitor
);
193 /* worker + event reference */
194 worker
->refcount
= 2;
200 struct udev_device
*dev
= NULL
;
202 _cleanup_rtnl_unref_ sd_rtnl
*rtnl
= NULL
;
203 struct epoll_event ep_signal
, ep_monitor
;
205 int rc
= EXIT_SUCCESS
;
207 /* take initial device from queue */
212 worker_list_cleanup(udev
);
213 event_queue_cleanup(udev
, EVENT_UNDEF
);
214 udev_monitor_unref(monitor
);
215 udev_ctrl_unref(udev_ctrl
);
218 close(worker_watch
[READ_END
]);
221 fd_signal
= signalfd(-1, &mask
, SFD_NONBLOCK
|SFD_CLOEXEC
);
223 log_error("error creating signalfd %m");
228 fd_ep
= epoll_create1(EPOLL_CLOEXEC
);
230 log_error("error creating epoll fd: %m");
235 memzero(&ep_signal
, sizeof(struct epoll_event
));
236 ep_signal
.events
= EPOLLIN
;
237 ep_signal
.data
.fd
= fd_signal
;
239 fd_monitor
= udev_monitor_get_fd(worker_monitor
);
240 memzero(&ep_monitor
, sizeof(struct epoll_event
));
241 ep_monitor
.events
= EPOLLIN
;
242 ep_monitor
.data
.fd
= fd_monitor
;
244 if (epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_signal
, &ep_signal
) < 0 ||
245 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_monitor
, &ep_monitor
) < 0) {
246 log_error("fail to add fds to epoll: %m");
251 /* request TERM signal if parent exits */
252 prctl(PR_SET_PDEATHSIG
, SIGTERM
);
254 /* reset OOM score, we only protect the main daemon */
255 write_string_file("/proc/self/oom_score_adj", "0");
258 struct udev_event
*udev_event
;
259 struct worker_message msg
;
263 log_debug("seq %llu running", udev_device_get_seqnum(dev
));
264 udev_event
= udev_event_new(dev
);
265 if (udev_event
== NULL
) {
270 /* needed for SIGCHLD/SIGTERM in spawn() */
271 udev_event
->fd_signal
= fd_signal
;
273 if (arg_exec_delay
> 0)
274 udev_event
->exec_delay
= arg_exec_delay
;
277 * Take a shared lock on the device node; this establishes
278 * a concept of device "ownership" to serialize device
279 * access. External processes holding an exclusive lock will
280 * cause udev to skip the event handling; in the case udev
281 * acquired the lock, the external process can block until
282 * udev has finished its event handling.
284 if (!streq_ptr(udev_device_get_action(dev
), "remove") &&
285 streq_ptr("block", udev_device_get_subsystem(dev
)) &&
286 !startswith(udev_device_get_sysname(dev
), "dm-") &&
287 !startswith(udev_device_get_sysname(dev
), "md")) {
288 struct udev_device
*d
= dev
;
290 if (streq_ptr("partition", udev_device_get_devtype(d
)))
291 d
= udev_device_get_parent(d
);
294 fd_lock
= open(udev_device_get_devnode(d
), O_RDONLY
|O_CLOEXEC
|O_NOFOLLOW
|O_NONBLOCK
);
295 if (fd_lock
>= 0 && flock(fd_lock
, LOCK_SH
|LOCK_NB
) < 0) {
296 log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d
));
298 fd_lock
= safe_close(fd_lock
);
304 /* needed for renaming netifs */
305 udev_event
->rtnl
= rtnl
;
307 /* apply rules, create node, symlinks */
308 udev_event_execute_rules(udev_event
,
309 arg_event_timeout_usec
, arg_event_timeout_warn_usec
,
314 udev_event_execute_run(udev_event
,
315 arg_event_timeout_usec
, arg_event_timeout_warn_usec
,
318 /* in case rtnl was initialized */
319 rtnl
= sd_rtnl_ref(udev_event
->rtnl
);
321 /* apply/restore inotify watch */
322 if (udev_event
->inotify_watch
) {
323 udev_watch_begin(udev
, dev
);
324 udev_device_update_db(dev
);
329 /* send processed event back to libudev listeners */
330 udev_monitor_send_device(worker_monitor
, NULL
, dev
);
333 /* send udevd the result of the event execution */
334 memzero(&msg
, sizeof(struct worker_message
));
337 send(worker_watch
[WRITE_END
], &msg
, sizeof(struct worker_message
), 0);
339 log_debug("seq %llu processed with %i", udev_device_get_seqnum(dev
), err
);
341 udev_device_unref(dev
);
344 if (udev_event
->sigterm
) {
345 udev_event_unref(udev_event
);
349 udev_event_unref(udev_event
);
351 /* wait for more device messages from main udevd, or term signal */
352 while (dev
== NULL
) {
353 struct epoll_event ev
[4];
357 fdcount
= epoll_wait(fd_ep
, ev
, ELEMENTSOF(ev
), -1);
361 log_error("failed to poll: %m");
365 for (i
= 0; i
< fdcount
; i
++) {
366 if (ev
[i
].data
.fd
== fd_monitor
&& ev
[i
].events
& EPOLLIN
) {
367 dev
= udev_monitor_receive_device(worker_monitor
);
369 } else if (ev
[i
].data
.fd
== fd_signal
&& ev
[i
].events
& EPOLLIN
) {
370 struct signalfd_siginfo fdsi
;
373 size
= read(fd_signal
, &fdsi
, sizeof(struct signalfd_siginfo
));
374 if (size
!= sizeof(struct signalfd_siginfo
))
376 switch (fdsi
.ssi_signo
) {
385 udev_device_unref(dev
);
386 safe_close(fd_signal
);
389 close(worker_watch
[WRITE_END
]);
390 udev_rules_unref(rules
);
391 udev_builtin_exit(udev
);
392 udev_monitor_unref(worker_monitor
);
398 udev_monitor_unref(worker_monitor
);
399 event
->state
= EVENT_QUEUED
;
401 log_error("fork of child failed: %m");
404 /* close monitor, but keep address around */
405 udev_monitor_disconnect(worker_monitor
);
406 worker
->monitor
= worker_monitor
;
408 worker
->state
= WORKER_RUNNING
;
409 worker
->event_start_usec
= now(CLOCK_MONOTONIC
);
410 worker
->event_warned
= false;
411 worker
->event
= event
;
412 event
->state
= EVENT_RUNNING
;
413 udev_list_node_append(&worker
->node
, &worker_list
);
415 log_debug("seq %llu forked new worker [%u]", udev_device_get_seqnum(event
->dev
), pid
);
420 static void event_run(struct event
*event
) {
421 struct udev_list_node
*loop
;
423 udev_list_node_foreach(loop
, &worker_list
) {
424 struct worker
*worker
= node_to_worker(loop
);
427 if (worker
->state
!= WORKER_IDLE
)
430 count
= udev_monitor_send_device(monitor
, worker
->monitor
, event
->dev
);
432 log_error("worker [%u] did not accept message %zi (%m), kill it", worker
->pid
, count
);
433 kill(worker
->pid
, SIGKILL
);
434 worker
->state
= WORKER_KILLED
;
438 worker
->event
= event
;
439 worker
->state
= WORKER_RUNNING
;
440 worker
->event_start_usec
= now(CLOCK_MONOTONIC
);
441 worker
->event_warned
= false;
442 event
->state
= EVENT_RUNNING
;
446 if (children
>= arg_children_max
) {
447 if (arg_children_max
> 1)
448 log_debug("maximum number (%i) of children reached", children
);
452 /* start new worker and pass initial device */
456 static int event_queue_insert(struct udev_device
*dev
) {
459 event
= new0(struct event
, 1);
463 event
->udev
= udev_device_get_udev(dev
);
465 event
->seqnum
= udev_device_get_seqnum(dev
);
466 event
->devpath
= udev_device_get_devpath(dev
);
467 event
->devpath_len
= strlen(event
->devpath
);
468 event
->devpath_old
= udev_device_get_devpath_old(dev
);
469 event
->devnum
= udev_device_get_devnum(dev
);
470 event
->is_block
= streq("block", udev_device_get_subsystem(dev
));
471 event
->ifindex
= udev_device_get_ifindex(dev
);
473 log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev
),
474 udev_device_get_action(dev
), udev_device_get_subsystem(dev
));
476 event
->state
= EVENT_QUEUED
;
477 udev_list_node_append(&event
->node
, &event_list
);
481 static void worker_kill(struct udev
*udev
) {
482 struct udev_list_node
*loop
;
484 udev_list_node_foreach(loop
, &worker_list
) {
485 struct worker
*worker
= node_to_worker(loop
);
487 if (worker
->state
== WORKER_KILLED
)
490 worker
->state
= WORKER_KILLED
;
491 kill(worker
->pid
, SIGTERM
);
495 /* lookup event for identical, parent, child device */
496 static bool is_devpath_busy(struct event
*event
) {
497 struct udev_list_node
*loop
;
500 /* check if queue contains events we depend on */
501 udev_list_node_foreach(loop
, &event_list
) {
502 struct event
*loop_event
= node_to_event(loop
);
504 /* we already found a later event, earlier can not block us, no need to check again */
505 if (loop_event
->seqnum
< event
->delaying_seqnum
)
508 /* event we checked earlier still exists, no need to check again */
509 if (loop_event
->seqnum
== event
->delaying_seqnum
)
512 /* found ourself, no later event can block us */
513 if (loop_event
->seqnum
>= event
->seqnum
)
516 /* check major/minor */
517 if (major(event
->devnum
) != 0 && event
->devnum
== loop_event
->devnum
&& event
->is_block
== loop_event
->is_block
)
520 /* check network device ifindex */
521 if (event
->ifindex
!= 0 && event
->ifindex
== loop_event
->ifindex
)
524 /* check our old name */
525 if (event
->devpath_old
!= NULL
&& streq(loop_event
->devpath
, event
->devpath_old
)) {
526 event
->delaying_seqnum
= loop_event
->seqnum
;
530 /* compare devpath */
531 common
= MIN(loop_event
->devpath_len
, event
->devpath_len
);
533 /* one devpath is contained in the other? */
534 if (memcmp(loop_event
->devpath
, event
->devpath
, common
) != 0)
537 /* identical device event found */
538 if (loop_event
->devpath_len
== event
->devpath_len
) {
539 /* devices names might have changed/swapped in the meantime */
540 if (major(event
->devnum
) != 0 && (event
->devnum
!= loop_event
->devnum
|| event
->is_block
!= loop_event
->is_block
))
542 if (event
->ifindex
!= 0 && event
->ifindex
!= loop_event
->ifindex
)
544 event
->delaying_seqnum
= loop_event
->seqnum
;
548 /* parent device event found */
549 if (event
->devpath
[common
] == '/') {
550 event
->delaying_seqnum
= loop_event
->seqnum
;
554 /* child device event found */
555 if (loop_event
->devpath
[common
] == '/') {
556 event
->delaying_seqnum
= loop_event
->seqnum
;
560 /* no matching device */
567 static void event_queue_start(struct udev
*udev
) {
568 struct udev_list_node
*loop
;
570 udev_list_node_foreach(loop
, &event_list
) {
571 struct event
*event
= node_to_event(loop
);
573 if (event
->state
!= EVENT_QUEUED
)
576 /* do not start event if parent or child event is still running */
577 if (is_devpath_busy(event
))
584 static void event_queue_cleanup(struct udev
*udev
, enum event_state match_type
) {
585 struct udev_list_node
*loop
, *tmp
;
587 udev_list_node_foreach_safe(loop
, tmp
, &event_list
) {
588 struct event
*event
= node_to_event(loop
);
590 if (match_type
!= EVENT_UNDEF
&& match_type
!= event
->state
)
593 event_queue_delete(event
);
597 static void worker_returned(int fd_worker
) {
599 struct worker_message msg
;
601 struct udev_list_node
*loop
;
603 size
= recv(fd_worker
, &msg
, sizeof(struct worker_message
), MSG_DONTWAIT
);
604 if (size
!= sizeof(struct worker_message
))
607 /* lookup worker who sent the signal */
608 udev_list_node_foreach(loop
, &worker_list
) {
609 struct worker
*worker
= node_to_worker(loop
);
611 if (worker
->pid
!= msg
.pid
)
614 /* worker returned */
616 worker
->event
->exitcode
= msg
.exitcode
;
617 event_queue_delete(worker
->event
);
618 worker
->event
= NULL
;
620 if (worker
->state
!= WORKER_KILLED
)
621 worker
->state
= WORKER_IDLE
;
622 worker_unref(worker
);
628 /* receive the udevd message from userspace */
629 static struct udev_ctrl_connection
*handle_ctrl_msg(struct udev_ctrl
*uctrl
) {
630 struct udev
*udev
= udev_ctrl_get_udev(uctrl
);
631 struct udev_ctrl_connection
*ctrl_conn
;
632 struct udev_ctrl_msg
*ctrl_msg
= NULL
;
636 ctrl_conn
= udev_ctrl_get_connection(uctrl
);
637 if (ctrl_conn
== NULL
)
640 ctrl_msg
= udev_ctrl_receive_msg(ctrl_conn
);
641 if (ctrl_msg
== NULL
)
644 i
= udev_ctrl_get_set_log_level(ctrl_msg
);
646 log_debug("udevd message (SET_LOG_LEVEL) received, log_priority=%i", i
);
647 log_set_max_level(i
);
651 if (udev_ctrl_get_stop_exec_queue(ctrl_msg
) > 0) {
652 log_debug("udevd message (STOP_EXEC_QUEUE) received");
653 stop_exec_queue
= true;
656 if (udev_ctrl_get_start_exec_queue(ctrl_msg
) > 0) {
657 log_debug("udevd message (START_EXEC_QUEUE) received");
658 stop_exec_queue
= false;
661 if (udev_ctrl_get_reload(ctrl_msg
) > 0) {
662 log_debug("udevd message (RELOAD) received");
666 str
= udev_ctrl_get_set_env(ctrl_msg
);
674 val
= strchr(key
, '=');
678 if (val
[0] == '\0') {
679 log_debug("udevd message (ENV) received, unset '%s'", key
);
680 udev_list_entry_add(&properties_list
, key
, NULL
);
682 log_debug("udevd message (ENV) received, set '%s=%s'", key
, val
);
683 udev_list_entry_add(&properties_list
, key
, val
);
686 log_error("wrong key format '%s'", key
);
693 i
= udev_ctrl_get_set_children_max(ctrl_msg
);
695 log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i", i
);
696 arg_children_max
= i
;
699 if (udev_ctrl_get_ping(ctrl_msg
) > 0)
700 log_debug("udevd message (SYNC) received");
702 if (udev_ctrl_get_exit(ctrl_msg
) > 0) {
703 log_debug("udevd message (EXIT) received");
705 /* keep reference to block the client until we exit */
706 udev_ctrl_connection_ref(ctrl_conn
);
709 udev_ctrl_msg_unref(ctrl_msg
);
710 return udev_ctrl_connection_unref(ctrl_conn
);
713 static int synthesize_change(struct udev_device
*dev
) {
714 char filename
[UTIL_PATH_SIZE
];
717 if (streq_ptr("block", udev_device_get_subsystem(dev
)) &&
718 streq_ptr("disk", udev_device_get_devtype(dev
)) &&
719 !startswith(udev_device_get_sysname(dev
), "dm-")) {
720 bool part_table_read
= false;
721 bool has_partitions
= false;
723 struct udev
*udev
= udev_device_get_udev(dev
);
724 _cleanup_udev_enumerate_unref_
struct udev_enumerate
*e
= NULL
;
725 struct udev_list_entry
*item
;
728 * Try to re-read the partition table. This only succeeds if
729 * none of the devices is busy. The kernel returns 0 if no
730 * partition table is found, and we will not get an event for
733 fd
= open(udev_device_get_devnode(dev
), O_RDONLY
|O_CLOEXEC
|O_NOFOLLOW
|O_NONBLOCK
);
735 r
= flock(fd
, LOCK_EX
|LOCK_NB
);
737 r
= ioctl(fd
, BLKRRPART
, 0);
741 part_table_read
= true;
744 /* search for partitions */
745 e
= udev_enumerate_new(udev
);
749 r
= udev_enumerate_add_match_parent(e
, dev
);
753 r
= udev_enumerate_add_match_subsystem(e
, "block");
757 r
= udev_enumerate_scan_devices(e
);
761 udev_list_entry_foreach(item
, udev_enumerate_get_list_entry(e
)) {
762 _cleanup_udev_device_unref_
struct udev_device
*d
= NULL
;
764 d
= udev_device_new_from_syspath(udev
, udev_list_entry_get_name(item
));
768 if (!streq_ptr("partition", udev_device_get_devtype(d
)))
771 has_partitions
= true;
776 * We have partitions and re-read the table, the kernel already sent
777 * out a "change" event for the disk, and "remove/add" for all
780 if (part_table_read
&& has_partitions
)
784 * We have partitions but re-reading the partition table did not
785 * work, synthesize "change" for the disk and all partitions.
787 log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev
));
788 strscpyl(filename
, sizeof(filename
), udev_device_get_syspath(dev
), "/uevent", NULL
);
789 write_string_file(filename
, "change");
791 udev_list_entry_foreach(item
, udev_enumerate_get_list_entry(e
)) {
792 _cleanup_udev_device_unref_
struct udev_device
*d
= NULL
;
794 d
= udev_device_new_from_syspath(udev
, udev_list_entry_get_name(item
));
798 if (!streq_ptr("partition", udev_device_get_devtype(d
)))
801 log_debug("device %s closed, synthesising partition '%s' 'change'",
802 udev_device_get_devnode(dev
), udev_device_get_devnode(d
));
803 strscpyl(filename
, sizeof(filename
), udev_device_get_syspath(d
), "/uevent", NULL
);
804 write_string_file(filename
, "change");
810 log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev
));
811 strscpyl(filename
, sizeof(filename
), udev_device_get_syspath(dev
), "/uevent", NULL
);
812 write_string_file(filename
, "change");
817 static int handle_inotify(struct udev
*udev
) {
820 struct inotify_event
*ev
;
823 r
= ioctl(fd_inotify
, FIONREAD
, &nbytes
);
824 if (r
< 0 || nbytes
<= 0)
827 buf
= malloc(nbytes
);
829 log_error("error getting buffer for inotify");
833 nbytes
= read(fd_inotify
, buf
, nbytes
);
835 for (pos
= 0; pos
< nbytes
; pos
+= sizeof(struct inotify_event
) + ev
->len
) {
836 struct udev_device
*dev
;
838 ev
= (struct inotify_event
*)(buf
+ pos
);
839 dev
= udev_watch_lookup(udev
, ev
->wd
);
843 log_debug("inotify event: %x for %s", ev
->mask
, udev_device_get_devnode(dev
));
844 if (ev
->mask
& IN_CLOSE_WRITE
)
845 synthesize_change(dev
);
846 else if (ev
->mask
& IN_IGNORED
)
847 udev_watch_end(udev
, dev
);
849 udev_device_unref(dev
);
856 static void handle_signal(struct udev
*udev
, int signo
) {
866 struct udev_list_node
*loop
, *tmp
;
868 pid
= waitpid(-1, &status
, WNOHANG
);
872 udev_list_node_foreach_safe(loop
, tmp
, &worker_list
) {
873 struct worker
*worker
= node_to_worker(loop
);
875 if (worker
->pid
!= pid
)
877 log_debug("worker [%u] exit", pid
);
879 if (WIFEXITED(status
)) {
880 if (WEXITSTATUS(status
) != 0)
881 log_error("worker [%u] exit with return code %i",
882 pid
, WEXITSTATUS(status
));
883 } else if (WIFSIGNALED(status
)) {
884 log_error("worker [%u] terminated by signal %i (%s)",
885 pid
, WTERMSIG(status
), strsignal(WTERMSIG(status
)));
886 } else if (WIFSTOPPED(status
)) {
887 log_error("worker [%u] stopped", pid
);
888 } else if (WIFCONTINUED(status
)) {
889 log_error("worker [%u] continued", pid
);
891 log_error("worker [%u] exit with status 0x%04x", pid
, status
);
894 if (!WIFEXITED(status
) || WEXITSTATUS(status
) != 0) {
896 log_error("worker [%u] failed while handling '%s'",
897 pid
, worker
->event
->devpath
);
898 worker
->event
->exitcode
= -32;
899 event_queue_delete(worker
->event
);
901 /* drop reference taken for state 'running' */
902 worker_unref(worker
);
905 worker_unref(worker
);
916 static int systemd_fds(struct udev
*udev
, int *rctrl
, int *rnetlink
) {
917 int ctrl
= -1, netlink
= -1;
920 n
= sd_listen_fds(true);
924 for (fd
= SD_LISTEN_FDS_START
; fd
< n
+ SD_LISTEN_FDS_START
; fd
++) {
925 if (sd_is_socket(fd
, AF_LOCAL
, SOCK_SEQPACKET
, -1)) {
932 if (sd_is_socket(fd
, AF_NETLINK
, SOCK_RAW
, -1)) {
942 if (ctrl
< 0 || netlink
< 0)
945 log_debug("ctrl=%i netlink=%i", ctrl
, netlink
);
952 * read the kernel command line, in case we need to get into debug mode
953 * udev.log-priority=<level> syslog priority
954 * udev.children-max=<number of workers> events are fully serialized if set to 1
955 * udev.exec-delay=<number of seconds> delay execution of every executed program
957 static void kernel_cmdline_options(struct udev
*udev
) {
958 _cleanup_free_
char *line
= NULL
;
959 const char *word
, *state
;
963 r
= proc_cmdline(&line
);
965 log_warning_errno(r
, "Failed to read /proc/cmdline, ignoring: %m");
969 FOREACH_WORD_QUOTED(word
, l
, line
, state
) {
970 char *s
, *opt
, *value
;
972 s
= strndup(word
, l
);
976 /* accept the same options for the initrd, prefixed with "rd." */
977 if (in_initrd() && startswith(s
, "rd."))
982 if ((value
= startswith(opt
, "udev.log-priority="))) {
985 prio
= util_log_priority(value
);
986 log_set_max_level(prio
);
987 } else if ((value
= startswith(opt
, "udev.children-max="))) {
988 r
= safe_atoi(value
, &arg_children_max
);
990 log_warning("Invalid udev.children-max ignored: %s", value
);
991 } else if ((value
= startswith(opt
, "udev.exec-delay="))) {
992 r
= safe_atoi(value
, &arg_exec_delay
);
994 log_warning("Invalid udev.exec-delay ignored: %s", value
);
995 } else if ((value
= startswith(opt
, "udev.event-timeout="))) {
996 r
= safe_atou64(value
, &arg_event_timeout_usec
);
998 log_warning("Invalid udev.event-timeout ignored: %s", value
);
1001 arg_event_timeout_usec
*= USEC_PER_SEC
;
1002 arg_event_timeout_warn_usec
= (arg_event_timeout_usec
/ 3) ? : 1;
1009 static void help(void) {
1010 printf("%s [OPTIONS...]\n\n"
1011 "Manages devices.\n\n"
1014 " --children-max=<maximum number of workers>\n"
1015 " --exec-delay=<seconds to wait before executing RUN=>\n"
1016 " --event-timeout=<seconds to wait before terminating an event>\n"
1017 " --resolve-names=early|late|never\n"
1020 , program_invocation_short_name
);
1023 static int parse_argv(int argc
, char *argv
[]) {
1024 static const struct option options
[] = {
1025 { "daemon", no_argument
, NULL
, 'd' },
1026 { "debug", no_argument
, NULL
, 'D' },
1027 { "children-max", required_argument
, NULL
, 'c' },
1028 { "exec-delay", required_argument
, NULL
, 'e' },
1029 { "event-timeout", required_argument
, NULL
, 't' },
1030 { "resolve-names", required_argument
, NULL
, 'N' },
1031 { "help", no_argument
, NULL
, 'h' },
1032 { "version", no_argument
, NULL
, 'V' },
1041 while ((c
= getopt_long(argc
, argv
, "c:de:DtN:hV", options
, NULL
)) >= 0) {
1047 arg_daemonize
= true;
1050 r
= safe_atoi(optarg
, &arg_children_max
);
1052 log_warning("Invalid --children-max ignored: %s", optarg
);
1055 r
= safe_atoi(optarg
, &arg_exec_delay
);
1057 log_warning("Invalid --exec-delay ignored: %s", optarg
);
1060 r
= safe_atou64(optarg
, &arg_event_timeout_usec
);
1062 log_warning("Invalid --event-timeout ignored: %s", optarg
);
1064 arg_event_timeout_usec
*= USEC_PER_SEC
;
1065 arg_event_timeout_warn_usec
= (arg_event_timeout_usec
/ 3) ? : 1;
1072 if (streq(optarg
, "early")) {
1073 arg_resolve_names
= 1;
1074 } else if (streq(optarg
, "late")) {
1075 arg_resolve_names
= 0;
1076 } else if (streq(optarg
, "never")) {
1077 arg_resolve_names
= -1;
1079 log_error("resolve-names must be early, late or never");
1087 printf("%s\n", VERSION
);
1092 assert_not_reached("Unhandled option");
1100 int main(int argc
, char *argv
[]) {
1104 int fd_netlink
= -1;
1106 struct epoll_event ep_ctrl
= { .events
= EPOLLIN
};
1107 struct epoll_event ep_inotify
= { .events
= EPOLLIN
};
1108 struct epoll_event ep_signal
= { .events
= EPOLLIN
};
1109 struct epoll_event ep_netlink
= { .events
= EPOLLIN
};
1110 struct epoll_event ep_worker
= { .events
= EPOLLIN
};
1111 struct udev_ctrl_connection
*ctrl_conn
= NULL
;
1118 log_set_target(LOG_TARGET_AUTO
);
1119 log_parse_environment();
1122 r
= parse_argv(argc
, argv
);
1126 kernel_cmdline_options(udev
);
1129 log_set_max_level(LOG_DEBUG
);
1131 if (getuid() != 0) {
1132 log_error("root privileges required");
1136 r
= mac_selinux_init("/dev");
1138 log_error_errno(r
, "could not initialize labelling: %m");
1142 /* set umask before creating any file/directory */
1145 log_error("could not change dir to /: %m");
1151 udev_list_init(udev
, &properties_list
, true);
1153 r
= mkdir("/run/udev", 0755);
1154 if (r
< 0 && errno
!= EEXIST
) {
1155 log_error("could not create /run/udev: %m");
1161 /* before opening new files, make sure std{in,out,err} fds are in a sane state */
1162 if (arg_daemonize
) {
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 log_error("cannot open /dev/null");
1178 if (systemd_fds(udev
, &fd_ctrl
, &fd_netlink
) >= 0) {
1179 /* get control and netlink socket from systemd */
1180 udev_ctrl
= udev_ctrl_new_from_fd(udev
, fd_ctrl
);
1181 if (udev_ctrl
== NULL
) {
1182 log_error("error taking over udev control socket");
1187 monitor
= udev_monitor_new_from_netlink_fd(udev
, "kernel", fd_netlink
);
1188 if (monitor
== NULL
) {
1189 log_error("error taking over netlink socket");
1194 /* get our own cgroup, we regularly kill everything udev has left behind */
1195 if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER
, 0, &udev_cgroup
) < 0)
1198 /* open control and netlink socket */
1199 udev_ctrl
= udev_ctrl_new(udev
);
1200 if (udev_ctrl
== NULL
) {
1201 log_error("error initializing udev control socket");
1205 fd_ctrl
= udev_ctrl_get_fd(udev_ctrl
);
1207 monitor
= udev_monitor_new_from_netlink(udev
, "kernel");
1208 if (monitor
== NULL
) {
1209 log_error("error initializing netlink socket");
1213 fd_netlink
= udev_monitor_get_fd(monitor
);
1216 if (udev_monitor_enable_receiving(monitor
) < 0) {
1217 log_error("error binding netlink socket");
1222 if (udev_ctrl_enable_receiving(udev_ctrl
) < 0) {
1223 log_error("error binding udev control socket");
1228 udev_monitor_set_receive_buffer_size(monitor
, 128 * 1024 * 1024);
1230 log_info("starting version " VERSION
);
1232 udev_builtin_init(udev
);
1234 rules
= udev_rules_new(udev
, arg_resolve_names
);
1235 if (rules
== NULL
) {
1236 log_error("error reading rules");
1240 rc
= udev_rules_apply_static_dev_perms(rules
);
1242 log_error_errno(rc
, "failed to apply permissions on static device nodes - %m");
1244 if (arg_daemonize
) {
1252 log_error("fork of daemon failed: %m");
1257 goto exit_daemonize
;
1262 write_string_file("/proc/self/oom_score_adj", "-1000");
1264 sd_notify(1, "READY=1");
1267 if (arg_children_max
<= 0) {
1270 arg_children_max
= 8;
1272 if (sched_getaffinity(0, sizeof (cpu_set
), &cpu_set
) == 0) {
1273 arg_children_max
+= CPU_COUNT(&cpu_set
) * 2;
1276 log_debug("set children_max to %u", arg_children_max
);
1278 udev_list_node_init(&event_list
);
1279 udev_list_node_init(&worker_list
);
1281 fd_inotify
= udev_watch_init(udev
);
1282 if (fd_inotify
< 0) {
1283 log_error("error initializing inotify");
1287 udev_watch_restore(udev
);
1289 /* block and listen to all signals on signalfd */
1291 sigprocmask(SIG_SETMASK
, &mask
, &sigmask_orig
);
1292 fd_signal
= signalfd(-1, &mask
, SFD_NONBLOCK
|SFD_CLOEXEC
);
1293 if (fd_signal
< 0) {
1294 log_error("error creating signalfd");
1299 /* unnamed socket from workers to the main daemon */
1300 if (socketpair(AF_LOCAL
, SOCK_DGRAM
|SOCK_CLOEXEC
, 0, worker_watch
) < 0) {
1301 log_error("error creating socketpair");
1305 fd_worker
= worker_watch
[READ_END
];
1307 ep_ctrl
.data
.fd
= fd_ctrl
;
1308 ep_inotify
.data
.fd
= fd_inotify
;
1309 ep_signal
.data
.fd
= fd_signal
;
1310 ep_netlink
.data
.fd
= fd_netlink
;
1311 ep_worker
.data
.fd
= fd_worker
;
1313 fd_ep
= epoll_create1(EPOLL_CLOEXEC
);
1315 log_error("error creating epoll fd: %m");
1318 if (epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_ctrl
, &ep_ctrl
) < 0 ||
1319 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_inotify
, &ep_inotify
) < 0 ||
1320 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_signal
, &ep_signal
) < 0 ||
1321 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_netlink
, &ep_netlink
) < 0 ||
1322 epoll_ctl(fd_ep
, EPOLL_CTL_ADD
, fd_worker
, &ep_worker
) < 0) {
1323 log_error("fail to add fds to epoll: %m");
1328 static usec_t last_usec
;
1329 struct epoll_event ev
[8];
1332 bool is_worker
, is_signal
, is_inotify
, is_netlink
, is_ctrl
;
1336 /* close sources of new events and discard buffered events */
1338 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_ctrl
, NULL
);
1341 if (monitor
!= NULL
) {
1342 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_netlink
, NULL
);
1343 udev_monitor_unref(monitor
);
1346 if (fd_inotify
>= 0) {
1347 epoll_ctl(fd_ep
, EPOLL_CTL_DEL
, fd_inotify
, NULL
);
1352 /* discard queued events and kill workers */
1353 event_queue_cleanup(udev
, EVENT_QUEUED
);
1356 /* exit after all has cleaned up */
1357 if (udev_list_node_is_empty(&event_list
) && children
== 0)
1360 /* timeout at exit for workers to finish */
1361 timeout
= 30 * MSEC_PER_SEC
;
1362 } else if (udev_list_node_is_empty(&event_list
) && children
== 0) {
1366 /* cleanup possible left-over processes in our cgroup */
1368 cg_kill(SYSTEMD_CGROUP_CONTROLLER
, udev_cgroup
, SIGKILL
, false, true, NULL
);
1370 /* kill idle or hanging workers */
1371 timeout
= 3 * MSEC_PER_SEC
;
1374 /* tell settle that we are busy or idle */
1375 if (!udev_list_node_is_empty(&event_list
)) {
1378 fd
= open("/run/udev/queue", O_WRONLY
|O_CREAT
|O_CLOEXEC
|O_TRUNC
|O_NOFOLLOW
, 0444);
1382 unlink("/run/udev/queue");
1385 fdcount
= epoll_wait(fd_ep
, ev
, ELEMENTSOF(ev
), timeout
);
1390 struct udev_list_node
*loop
;
1394 log_error("timeout, giving up waiting for workers to finish");
1398 /* kill idle workers */
1399 if (udev_list_node_is_empty(&event_list
)) {
1400 log_debug("cleanup idle workers");
1404 /* check for hanging events */
1405 udev_list_node_foreach(loop
, &worker_list
) {
1406 struct worker
*worker
= node_to_worker(loop
);
1409 if (worker
->state
!= WORKER_RUNNING
)
1412 ts
= now(CLOCK_MONOTONIC
);
1414 if ((ts
- worker
->event_start_usec
) > arg_event_timeout_warn_usec
) {
1415 if ((ts
- worker
->event_start_usec
) > arg_event_timeout_usec
) {
1416 log_error("worker [%u] %s timeout; kill it", worker
->pid
, worker
->event
->devpath
);
1417 kill(worker
->pid
, SIGKILL
);
1418 worker
->state
= WORKER_KILLED
;
1420 /* drop reference taken for state 'running' */
1421 worker_unref(worker
);
1422 log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker
->event
->dev
), worker
->event
->devpath
);
1423 worker
->event
->exitcode
= -64;
1424 event_queue_delete(worker
->event
);
1425 worker
->event
= NULL
;
1426 } else if (!worker
->event_warned
) {
1427 log_warning("worker [%u] %s is taking a long time", worker
->pid
, worker
->event
->devpath
);
1428 worker
->event_warned
= true;
1435 is_worker
= is_signal
= is_inotify
= is_netlink
= is_ctrl
= false;
1436 for (i
= 0; i
< fdcount
; i
++) {
1437 if (ev
[i
].data
.fd
== fd_worker
&& ev
[i
].events
& EPOLLIN
)
1439 else if (ev
[i
].data
.fd
== fd_netlink
&& ev
[i
].events
& EPOLLIN
)
1441 else if (ev
[i
].data
.fd
== fd_signal
&& ev
[i
].events
& EPOLLIN
)
1443 else if (ev
[i
].data
.fd
== fd_inotify
&& ev
[i
].events
& EPOLLIN
)
1445 else if (ev
[i
].data
.fd
== fd_ctrl
&& ev
[i
].events
& EPOLLIN
)
1449 /* check for changed config, every 3 seconds at most */
1450 if ((now(CLOCK_MONOTONIC
) - last_usec
) > 3 * USEC_PER_SEC
) {
1451 if (udev_rules_check_timestamp(rules
))
1453 if (udev_builtin_validate(udev
))
1456 last_usec
= now(CLOCK_MONOTONIC
);
1459 /* reload requested, HUP signal received, rules changed, builtin changed */
1462 rules
= udev_rules_unref(rules
);
1463 udev_builtin_exit(udev
);
1467 /* event has finished */
1469 worker_returned(fd_worker
);
1472 struct udev_device
*dev
;
1474 dev
= udev_monitor_receive_device(monitor
);
1476 udev_device_set_usec_initialized(dev
, now(CLOCK_MONOTONIC
));
1477 if (event_queue_insert(dev
) < 0)
1478 udev_device_unref(dev
);
1482 /* start new events */
1483 if (!udev_list_node_is_empty(&event_list
) && !udev_exit
&& !stop_exec_queue
) {
1484 udev_builtin_init(udev
);
1486 rules
= udev_rules_new(udev
, arg_resolve_names
);
1488 event_queue_start(udev
);
1492 struct signalfd_siginfo fdsi
;
1495 size
= read(fd_signal
, &fdsi
, sizeof(struct signalfd_siginfo
));
1496 if (size
== sizeof(struct signalfd_siginfo
))
1497 handle_signal(udev
, fdsi
.ssi_signo
);
1500 /* we are shutting down, the events below are not handled anymore */
1504 /* device node watch */
1506 handle_inotify(udev
);
1509 * This needs to be after the inotify handling, to make sure,
1510 * that the ping is send back after the possibly generated
1511 * "change" events by the inotify device node watch.
1513 * A single time we may receive a client connection which we need to
1514 * keep open to block the client. It will be closed right before we
1518 ctrl_conn
= handle_ctrl_msg(udev_ctrl
);
1523 udev_ctrl_cleanup(udev_ctrl
);
1524 unlink("/run/udev/queue");
1528 worker_list_cleanup(udev
);
1529 event_queue_cleanup(udev
, EVENT_UNDEF
);
1530 udev_rules_unref(rules
);
1531 udev_builtin_exit(udev
);
1534 if (worker_watch
[READ_END
] >= 0)
1535 close(worker_watch
[READ_END
]);
1536 if (worker_watch
[WRITE_END
] >= 0)
1537 close(worker_watch
[WRITE_END
]);
1538 udev_monitor_unref(monitor
);
1539 udev_ctrl_connection_unref(ctrl_conn
);
1540 udev_ctrl_unref(udev_ctrl
);
1541 udev_list_cleanup(&properties_list
);
1542 mac_selinux_finish();