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 Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser 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>
49 #define FINALIZE_ATTEMPTS 50
51 static int prepare_new_root(void) {
52 static const char dirs[] =
53 "/run/initramfs/oldroot\0"
54 "/run/initramfs/proc\0"
55 "/run/initramfs/sys\0"
56 "/run/initramfs/dev\0"
57 "/run/initramfs/run\0";
61 if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0) {
62 log_error("Failed to mount bind /run/initramfs on /run/initramfs: %m");
66 if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0) {
67 log_error("Failed to make /run/initramfs private mount: %m");
71 NULSTR_FOREACH(dir, dirs)
72 if (mkdir_p_label(dir, 0755) < 0 && errno != EEXIST) {
73 log_error("Failed to mkdir %s: %m", dir);
77 if (mount("/sys", "/run/initramfs/sys", NULL, MS_BIND, NULL) < 0) {
78 log_error("Failed to mount bind /sys on /run/initramfs/sys: %m");
82 if (mount("/proc", "/run/initramfs/proc", NULL, MS_BIND, NULL) < 0) {
83 log_error("Failed to mount bind /proc on /run/initramfs/proc: %m");
87 if (mount("/dev", "/run/initramfs/dev", NULL, MS_BIND, NULL) < 0) {
88 log_error("Failed to mount bind /dev on /run/initramfs/dev: %m");
92 if (mount("/run", "/run/initramfs/run", NULL, MS_BIND, NULL) < 0) {
93 log_error("Failed to mount bind /run on /run/initramfs/run: %m");
100 static int pivot_to_new_root(void) {
102 if (chdir("/run/initramfs") < 0) {
103 log_error("Failed to change directory to /run/initramfs: %m");
107 /* Work-around for a kernel bug: for some reason the kernel
108 * refuses switching root if any file systems are mounted
109 * MS_SHARED. Hence remount them MS_PRIVATE here as a
112 * https://bugzilla.redhat.com/show_bug.cgi?id=847418 */
113 if (mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) < 0)
114 log_warning("Failed to make \"/\" private mount: %m");
116 if (pivot_root(".", "oldroot") < 0) {
117 log_error("pivot failed: %m");
118 /* only chroot if pivot root succeeded */
125 make_console_stdio();
127 log_info("Successfully changed into root pivot.");
132 int main(int argc, char *argv[]) {
135 bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true;
136 bool in_container, use_watchdog = false;
139 log_parse_environment();
140 log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */
146 log_error("Not executed by init (pid 1).");
152 log_error("Invalid number of arguments.");
157 in_container = detect_container(NULL) > 0;
159 if (streq(argv[1], "reboot"))
161 else if (streq(argv[1], "poweroff"))
163 else if (streq(argv[1], "halt"))
164 cmd = RB_HALT_SYSTEM;
165 else if (streq(argv[1], "kexec"))
166 cmd = LINUX_REBOOT_CMD_KEXEC;
168 log_error("Unknown action '%s'.", argv[1]);
173 use_watchdog = !!getenv("WATCHDOG_USEC");
175 /* lock us into memory */
176 mlockall(MCL_CURRENT|MCL_FUTURE);
178 log_info("Sending SIGTERM to remaining processes...");
179 broadcast_signal(SIGTERM, true);
181 log_info("Sending SIGKILL to remaining processes...");
182 broadcast_signal(SIGKILL, true);
185 need_swapoff = false;
186 need_dm_detach = false;
187 need_loop_detach = false;
190 /* Unmount all mountpoints, swaps, and loopback devices */
191 for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) {
192 bool changed = false;
198 log_info("Unmounting file systems.");
199 r = umount_all(&changed);
203 log_info("Not all file systems unmounted, %d left.", r);
205 log_error("Failed to unmount file systems: %s", strerror(-r));
209 log_info("Disabling swaps.");
210 r = swapoff_all(&changed);
212 need_swapoff = false;
214 log_info("Not all swaps are turned off, %d left.", r);
216 log_error("Failed to turn off swaps: %s", strerror(-r));
219 if (need_loop_detach) {
220 log_info("Detaching loop devices.");
221 r = loopback_detach_all(&changed);
223 need_loop_detach = false;
225 log_info("Not all loop devices detached, %d left.", r);
227 log_error("Failed to detach loop devices: %s", strerror(-r));
230 if (need_dm_detach) {
231 log_info("Detaching DM devices.");
232 r = dm_detach_all(&changed);
234 need_dm_detach = false;
236 log_warning("Not all DM devices detached, %d left.", r);
238 log_error("Failed to detach DM devices: %s", strerror(-r));
241 if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach) {
243 log_info("All filesystems, swaps, loop devices, DM devices detached.");
248 /* If in this iteration we didn't manage to
249 * unmount/deactivate anything, we simply give up */
251 log_error("Cannot finalize remaining file systems and devices, giving up.");
255 log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1);
258 if (retries >= FINALIZE_ATTEMPTS)
259 log_error("Too many iterations, giving up.");
262 arguments[1] = argv[1];
264 execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, arguments);
267 access("/run/initramfs/shutdown", X_OK) == 0) {
269 if (prepare_new_root() >= 0 &&
270 pivot_to_new_root() >= 0) {
271 execv("/shutdown", argv);
272 log_error("Failed to execute shutdown binary: %m");
276 if (cmd == LINUX_REBOOT_CMD_KEXEC) {
279 /* We cheat and exec kexec to avoid doing all its work */
283 log_error("Could not fork: %m. Falling back to normal reboot.");
285 wait_for_terminate_and_warn("kexec", pid);
286 log_warning("kexec failed. Falling back to normal reboot.");
289 const char *args[3] = { "/sbin/kexec", "-e", NULL };
290 execv(args[0], (char * const *) args);
300 if (errno == EPERM && in_container) {
301 /* If we are in a container, and we lacked
302 * CAP_SYS_BOOT just exit, this will kill our
303 * container for good. */
304 log_error("Exiting container.");
308 log_error("Failed to invoke reboot(): %m");
312 log_error("Critical error while doing system shutdown: %s", strerror(-r));