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>
45 #define TIMEOUT_USEC (5 * USEC_PER_SEC)
46 #define FINALIZE_ATTEMPTS 50
47 #define pivot_root(new_root,put_old) syscall(SYS_pivot_root,new_root,put_old)
49 static bool ignore_proc(pid_t pid) {
53 /* TODO: add more ignore rules here: device-mapper, etc */
58 static bool is_kernel_thread(pid_t pid)
65 snprintf(buf, sizeof(buf), "/proc/%lu/cmdline", (unsigned long)pid);
68 return true; /* not really, but has the desired effect */
70 count = fread(&c, 1, 1, f);
75 static int killall(int sign) {
78 unsigned int n_processes = 0;
80 if ((dir = opendir("/proc")) == NULL)
83 while ((d = readdir(dir))) {
86 if (parse_pid(d->d_name, &pid) < 0)
89 if (is_kernel_thread(pid))
95 if (kill(pid, sign) == 0)
98 log_warning("Could not kill %d: %m", pid);
106 static void wait_for_children(int n_processes, sigset_t *mask) {
111 until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC;
118 pid_t pid = waitpid(-1, NULL, WNOHANG);
123 if (pid < 0 && errno == ECHILD)
127 if (--n_processes == 0)
131 n = now(CLOCK_MONOTONIC);
135 timespec_store(&ts, until - n);
137 if ((k = sigtimedwait(mask, NULL, &ts)) != SIGCHLD) {
139 if (k < 0 && errno != EAGAIN) {
140 log_error("sigtimedwait() failed: %m");
145 log_warning("sigtimedwait() returned unexpected signal.");
150 static void send_signal(int sign) {
151 sigset_t mask, oldmask;
154 assert_se(sigemptyset(&mask) == 0);
155 assert_se(sigaddset(&mask, SIGCHLD) == 0);
156 assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0);
158 if (kill(-1, SIGSTOP) < 0 && errno != ESRCH)
159 log_warning("kill(-1, SIGSTOP) failed: %m");
161 n_processes = killall(sign);
163 if (kill(-1, SIGCONT) < 0 && errno != ESRCH)
164 log_warning("kill(-1, SIGCONT) failed: %m");
166 if (n_processes <= 0)
169 wait_for_children(n_processes, &mask);
172 sigprocmask(SIG_SETMASK, &oldmask, NULL);
175 static void ultimate_send_signal(int sign) {
176 sigset_t mask, oldmask;
179 assert_se(sigemptyset(&mask) == 0);
180 assert_se(sigaddset(&mask, SIGCHLD) == 0);
181 assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0);
183 if (kill(-1, SIGSTOP) < 0 && errno != ESRCH)
184 log_warning("kill(-1, SIGSTOP) failed: %m");
187 if (r < 0 && errno != ESRCH)
188 log_warning("kill(-1, %s) failed: %m", signal_to_string(sign));
190 if (kill(-1, SIGCONT) < 0 && errno != ESRCH)
191 log_warning("kill(-1, SIGCONT) failed: %m");
196 wait_for_children(0, &mask);
199 sigprocmask(SIG_SETMASK, &oldmask, NULL);
202 static bool prepare_new_root(void) {
204 const char *dirs[] = { "/run/initramfs/oldroot",
205 "/run/initramfs/proc",
206 "/run/initramfs/sys",
207 "/run/initramfs/dev",
208 "/run/initramfs/run",
213 msg = "Failed to mount bind /run/initramfs on /run/initramfs";
214 if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) != 0)
217 msg="Failed to make /run/initramfs private mount %m:";
218 if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) != 0)
221 for (dir = &dirs[0]; *dir != NULL; dir++) {
222 asprintf((char **) &msg, "mkdir %s: %%m", *dir);
223 if (mkdir(*dir, 0755) != 0) {
230 msg = "Failed to mount bind /sys on /run/initramfs/sys";
231 if (mount("/sys", "/run/initramfs/sys", NULL, MS_BIND, NULL) != 0)
233 msg = "Failed to mount bind /proc on /run/initramfs/proc";
234 if (mount("/proc", "/run/initramfs/proc", NULL, MS_BIND, NULL) != 0)
236 msg = "Failed to mount bind /dev on /run/initramfs/dev";
237 if (mount("/dev", "/run/initramfs/dev", NULL, MS_BIND, NULL) != 0)
239 msg = "Failed to mount bind /run on /run/initramfs/run";
240 if (mount("/run", "/run/initramfs/run", NULL, MS_BIND, NULL) != 0)
246 log_error("%s: %m", msg);
250 static bool pivot_to_new_root(void) {
253 chdir("/run/initramfs");
256 In case some evil process made "/" MS_SHARED
257 It works for pivot_root, but the ref count for the root device
258 is not decreasing :-/
260 if (mount(NULL, "/", NULL, MS_PRIVATE, NULL) != 0) {
261 log_error("Failed to make \"/\" private mount %m: ");
265 r = pivot_root(".", "oldroot");
267 log_error("pivot failed: %m");
268 /* only chroot, if pivot root succeded */
272 log_info("pivot rooted");
274 fd = open("dev/console", O_RDONLY);
275 dup2(fd, STDIN_FILENO);
276 close_nointr_nofail(fd);
277 fd = open("dev/console", O_WRONLY);
278 dup2(fd, STDOUT_FILENO);
279 close_nointr_nofail(fd);
280 fd = open("dev/console", O_WRONLY);
281 dup2(fd, STDERR_FILENO);
282 close_nointr_nofail(fd);
286 int main(int argc, char *argv[]) {
289 bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true;
290 bool killed_everbody = false, in_container;
292 log_parse_environment();
293 log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */
297 log_error("Not executed by init (pid 1).");
303 log_error("Invalid number of arguments.");
308 in_container = detect_container(NULL) > 0;
310 if (streq(argv[1], "reboot"))
312 else if (streq(argv[1], "poweroff"))
314 else if (streq(argv[1], "halt"))
315 cmd = RB_HALT_SYSTEM;
316 else if (streq(argv[1], "kexec"))
317 cmd = LINUX_REBOOT_CMD_KEXEC;
319 log_error("Unknown action '%s'.", argv[1]);
324 /* lock us into memory */
325 if (mlockall(MCL_CURRENT|MCL_FUTURE) != 0)
326 log_warning("Cannot lock process memory: %m");
328 log_info("Sending SIGTERM to remaining processes...");
329 send_signal(SIGTERM);
331 log_info("Sending SIGKILL to remaining processes...");
332 send_signal(SIGKILL);
335 need_swapoff = false;
337 /* Unmount all mountpoints, swaps, and loopback devices */
338 for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) {
339 bool changed = false;
342 log_info("Unmounting file systems.");
343 r = umount_all(&changed);
347 log_info("Not all file systems unmounted, %d left.", r);
349 log_error("Failed to unmount file systems: %s", strerror(-r));
353 log_info("Disabling swaps.");
354 r = swapoff_all(&changed);
356 need_swapoff = false;
358 log_info("Not all swaps are turned off, %d left.", r);
360 log_error("Failed to turn off swaps: %s", strerror(-r));
363 if (need_loop_detach) {
364 log_info("Detaching loop devices.");
365 r = loopback_detach_all(&changed);
367 need_loop_detach = false;
369 log_info("Not all loop devices detached, %d left.", r);
371 log_error("Failed to detach loop devices: %s", strerror(-r));
374 if (need_dm_detach) {
375 log_info("Detaching DM devices.");
376 r = dm_detach_all(&changed);
378 need_dm_detach = false;
380 log_warning("Not all DM devices detached, %d left.", r);
382 log_error("Failed to detach DM devices: %s", strerror(-r));
385 if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach)
389 /* If in this iteration we didn't manage to
390 * unmount/deactivate anything, we either kill more
391 * processes, or simply give up */
394 if (killed_everbody) {
395 /* Hmm, we already killed everybody,
396 * let's just give up */
397 log_error("Cannot finalize remaining file systems and devices, giving up.");
401 log_warning("Cannot finalize remaining file systems and devices, trying to kill remaining processes.");
402 ultimate_send_signal(SIGTERM);
403 ultimate_send_signal(SIGKILL);
404 killed_everbody = true;
407 log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1);
410 if (retries >= FINALIZE_ATTEMPTS)
411 log_error("Too many iterations, giving up.");
413 execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, NULL);
415 /* If we are in a container, just exit, this will kill our
416 * container for good. */
418 log_error("Exiting container.");
424 if (access("/run/initramfs/shutdown", X_OK) == 0) {
426 new_argv[0] = strdup(argv[0]);
427 new_argv[1] = strdup(argv[1]);
429 if (prepare_new_root() && pivot_to_new_root()) {
430 execv("/shutdown", new_argv);
431 log_error("Failed to execute shutdown binary: %m");
435 if (cmd == LINUX_REBOOT_CMD_KEXEC) {
436 /* We cheat and exec kexec to avoid doing all its work */
440 log_error("Could not fork: %m. Falling back to normal reboot.");
442 wait_for_terminate_and_warn("kexec", pid);
443 log_warning("kexec failed. Falling back to normal reboot.");
446 const char *args[3] = { "/sbin/kexec", "-e", NULL };
447 execv(args[0], (char * const *) args);
455 log_error("Failed to invoke reboot(): %m");
459 log_error("Critical error while doing system shutdown: %s", strerror(-r));