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git.ipfire.org Git - thirdparty/systemd.git/blob - src/shutdown.c
1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 ProFUSION embedded systems
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
23 #include <sys/types.h>
24 #include <sys/reboot.h>
25 #include <linux/reboot.h>
27 #include <sys/types.h>
29 #include <sys/mount.h>
30 #include <sys/syscall.h>
46 #define TIMEOUT_USEC (5 * USEC_PER_SEC)
47 #define FINALIZE_ATTEMPTS 50
49 static bool ignore_proc(pid_t pid
) {
57 /* We are PID 1, let's not commit suicide */
61 r
= get_process_uid(pid
, &uid
);
63 return true; /* not really, but better safe than sorry */
65 /* Non-root processes otherwise are always subject to be killed */
69 snprintf(buf
, sizeof(buf
), "/proc/%lu/cmdline", (unsigned long) pid
);
74 return true; /* not really, but has the desired effect */
76 count
= fread(&c
, 1, 1, f
);
79 /* Kernel threads have an empty cmdline */
83 /* Processes with argv[0][0] = '@' we ignore from the killing
86 * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons */
87 if (count
== 1 && c
== '@')
93 static int killall(int sign
) {
96 unsigned int n_processes
= 0;
98 dir
= opendir("/proc");
102 while ((d
= readdir(dir
))) {
105 if (parse_pid(d
->d_name
, &pid
) < 0)
108 if (ignore_proc(pid
))
111 if (kill(pid
, sign
) == 0)
114 log_warning("Could not kill %d: %m", pid
);
122 static void wait_for_children(int n_processes
, sigset_t
*mask
) {
127 until
= now(CLOCK_MONOTONIC
) + TIMEOUT_USEC
;
134 pid_t pid
= waitpid(-1, NULL
, WNOHANG
);
139 if (pid
< 0 && errno
== ECHILD
)
143 if (--n_processes
== 0)
147 n
= now(CLOCK_MONOTONIC
);
151 timespec_store(&ts
, until
- n
);
153 if ((k
= sigtimedwait(mask
, NULL
, &ts
)) != SIGCHLD
) {
155 if (k
< 0 && errno
!= EAGAIN
) {
156 log_error("sigtimedwait() failed: %m");
161 log_warning("sigtimedwait() returned unexpected signal.");
166 static void send_signal(int sign
) {
167 sigset_t mask
, oldmask
;
170 assert_se(sigemptyset(&mask
) == 0);
171 assert_se(sigaddset(&mask
, SIGCHLD
) == 0);
172 assert_se(sigprocmask(SIG_BLOCK
, &mask
, &oldmask
) == 0);
174 if (kill(-1, SIGSTOP
) < 0 && errno
!= ESRCH
)
175 log_warning("kill(-1, SIGSTOP) failed: %m");
177 n_processes
= killall(sign
);
179 if (kill(-1, SIGCONT
) < 0 && errno
!= ESRCH
)
180 log_warning("kill(-1, SIGCONT) failed: %m");
182 if (n_processes
<= 0)
185 wait_for_children(n_processes
, &mask
);
188 sigprocmask(SIG_SETMASK
, &oldmask
, NULL
);
191 static void ultimate_send_signal(int sign
) {
192 sigset_t mask
, oldmask
;
195 assert_se(sigemptyset(&mask
) == 0);
196 assert_se(sigaddset(&mask
, SIGCHLD
) == 0);
197 assert_se(sigprocmask(SIG_BLOCK
, &mask
, &oldmask
) == 0);
199 if (kill(-1, SIGSTOP
) < 0 && errno
!= ESRCH
)
200 log_warning("kill(-1, SIGSTOP) failed: %m");
203 if (r
< 0 && errno
!= ESRCH
)
204 log_warning("kill(-1, %s) failed: %m", signal_to_string(sign
));
206 if (kill(-1, SIGCONT
) < 0 && errno
!= ESRCH
)
207 log_warning("kill(-1, SIGCONT) failed: %m");
212 wait_for_children(0, &mask
);
215 sigprocmask(SIG_SETMASK
, &oldmask
, NULL
);
218 static int prepare_new_root(void) {
219 static const char dirs
[] =
220 "/run/initramfs/oldroot\0"
221 "/run/initramfs/proc\0"
222 "/run/initramfs/sys\0"
223 "/run/initramfs/dev\0"
224 "/run/initramfs/run\0";
228 if (mount("/run/initramfs", "/run/initramfs", NULL
, MS_BIND
, NULL
) < 0) {
229 log_error("Failed to mount bind /run/initramfs on /run/initramfs: %m");
233 if (mount(NULL
, "/run/initramfs", NULL
, MS_PRIVATE
, NULL
) < 0) {
234 log_error("Failed to make /run/initramfs private mount: %m");
238 NULSTR_FOREACH(dir
, dirs
)
239 if (mkdir_p(dir
, 0755) < 0 && errno
!= EEXIST
) {
240 log_error("Failed to mkdir %s: %m", dir
);
244 if (mount("/sys", "/run/initramfs/sys", NULL
, MS_BIND
, NULL
) < 0) {
245 log_error("Failed to mount bind /sys on /run/initramfs/sys: %m");
249 if (mount("/proc", "/run/initramfs/proc", NULL
, MS_BIND
, NULL
) < 0) {
250 log_error("Failed to mount bind /proc on /run/initramfs/proc: %m");
254 if (mount("/dev", "/run/initramfs/dev", NULL
, MS_BIND
, NULL
) < 0) {
255 log_error("Failed to mount bind /dev on /run/initramfs/dev: %m");
259 if (mount("/run", "/run/initramfs/run", NULL
, MS_BIND
, NULL
) < 0) {
260 log_error("Failed to mount bind /run on /run/initramfs/run: %m");
267 static int pivot_to_new_root(void) {
270 chdir("/run/initramfs");
273 In case some evil process made "/" MS_SHARED
274 It works for pivot_root, but the ref count for the root device
275 is not decreasing :-/
277 if (mount(NULL
, "/", NULL
, MS_PRIVATE
, NULL
) < 0) {
278 log_error("Failed to make \"/\" private mount %m");
282 if (pivot_root(".", "oldroot") < 0) {
283 log_error("pivot failed: %m");
284 /* only chroot if pivot root succeded */
289 log_info("Successfully changed into root pivot.");
291 fd
= open("/dev/console", O_RDWR
);
293 log_error("Failed to open /dev/console: %m");
297 /* Initialize the controlling terminal */
299 ioctl(STDIN_FILENO
, TIOCSCTTY
, NULL
);
305 int main(int argc
, char *argv
[]) {
308 bool need_umount
= true, need_swapoff
= true, need_loop_detach
= true, need_dm_detach
= true;
309 bool killed_everbody
= false, in_container
;
311 log_parse_environment();
312 log_set_target(LOG_TARGET_CONSOLE
); /* syslog will die if not gone yet */
318 log_error("Not executed by init (pid 1).");
324 log_error("Invalid number of arguments.");
329 in_container
= detect_container(NULL
) > 0;
331 if (streq(argv
[1], "reboot"))
333 else if (streq(argv
[1], "poweroff"))
335 else if (streq(argv
[1], "halt"))
336 cmd
= RB_HALT_SYSTEM
;
337 else if (streq(argv
[1], "kexec"))
338 cmd
= LINUX_REBOOT_CMD_KEXEC
;
340 log_error("Unknown action '%s'.", argv
[1]);
345 /* lock us into memory */
346 if (mlockall(MCL_CURRENT
|MCL_FUTURE
) != 0)
347 log_warning("Cannot lock process memory: %m");
349 log_info("Sending SIGTERM to remaining processes...");
350 send_signal(SIGTERM
);
352 log_info("Sending SIGKILL to remaining processes...");
353 send_signal(SIGKILL
);
356 need_swapoff
= false;
358 /* Unmount all mountpoints, swaps, and loopback devices */
359 for (retries
= 0; retries
< FINALIZE_ATTEMPTS
; retries
++) {
360 bool changed
= false;
363 log_info("Unmounting file systems.");
364 r
= umount_all(&changed
);
368 log_info("Not all file systems unmounted, %d left.", r
);
370 log_error("Failed to unmount file systems: %s", strerror(-r
));
374 log_info("Disabling swaps.");
375 r
= swapoff_all(&changed
);
377 need_swapoff
= false;
379 log_info("Not all swaps are turned off, %d left.", r
);
381 log_error("Failed to turn off swaps: %s", strerror(-r
));
384 if (need_loop_detach
) {
385 log_info("Detaching loop devices.");
386 r
= loopback_detach_all(&changed
);
388 need_loop_detach
= false;
390 log_info("Not all loop devices detached, %d left.", r
);
392 log_error("Failed to detach loop devices: %s", strerror(-r
));
395 if (need_dm_detach
) {
396 log_info("Detaching DM devices.");
397 r
= dm_detach_all(&changed
);
399 need_dm_detach
= false;
401 log_warning("Not all DM devices detached, %d left.", r
);
403 log_error("Failed to detach DM devices: %s", strerror(-r
));
406 if (!need_umount
&& !need_swapoff
&& !need_loop_detach
&& !need_dm_detach
) {
408 log_info("All filesystems, swaps, loop devices, DM devices detached.");
413 /* If in this iteration we didn't manage to
414 * unmount/deactivate anything, we either kill more
415 * processes, or simply give up */
418 if (killed_everbody
) {
419 /* Hmm, we already killed everybody,
420 * let's just give up */
421 log_error("Cannot finalize remaining file systems and devices, giving up.");
425 log_warning("Cannot finalize remaining file systems and devices, trying to kill remaining processes.");
426 ultimate_send_signal(SIGTERM
);
427 ultimate_send_signal(SIGKILL
);
428 killed_everbody
= true;
431 log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries
+1);
434 if (retries
>= FINALIZE_ATTEMPTS
)
435 log_error("Too many iterations, giving up.");
437 execute_directory(SYSTEM_SHUTDOWN_PATH
, NULL
, NULL
);
439 /* If we are in a container, just exit, this will kill our
440 * container for good. */
442 log_error("Exiting container.");
446 if (access("/run/initramfs/shutdown", X_OK
) == 0) {
448 if (prepare_new_root() >= 0 &&
449 pivot_to_new_root() >= 0) {
450 execv("/shutdown", argv
);
451 log_error("Failed to execute shutdown binary: %m");
457 if (cmd
== LINUX_REBOOT_CMD_KEXEC
) {
458 /* We cheat and exec kexec to avoid doing all its work */
462 log_error("Could not fork: %m. Falling back to normal reboot.");
464 wait_for_terminate_and_warn("kexec", pid
);
465 log_warning("kexec failed. Falling back to normal reboot.");
468 const char *args
[3] = { "/sbin/kexec", "-e", NULL
};
469 execv(args
[0], (char * const *) args
);
477 log_error("Failed to invoke reboot(): %m");
481 log_error("Critical error while doing system shutdown: %s", strerror(-r
));