summaryrefslogtreecommitdiff
path: root/src/core/shutdown.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/core/shutdown.c')
-rw-r--r--src/core/shutdown.c316
1 files changed, 316 insertions, 0 deletions
diff --git a/src/core/shutdown.c b/src/core/shutdown.c
new file mode 100644
index 0000000000..cc8c57bd2d
--- /dev/null
+++ b/src/core/shutdown.c
@@ -0,0 +1,316 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 ProFUSION embedded systems
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/reboot.h>
+#include <linux/reboot.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+#include <sys/syscall.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <errno.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "missing.h"
+#include "log.h"
+#include "umount.h"
+#include "util.h"
+#include "mkdir.h"
+#include "virt.h"
+#include "watchdog.h"
+#include "killall.h"
+
+#define FINALIZE_ATTEMPTS 50
+
+static int prepare_new_root(void) {
+ static const char dirs[] =
+ "/run/initramfs/oldroot\0"
+ "/run/initramfs/proc\0"
+ "/run/initramfs/sys\0"
+ "/run/initramfs/dev\0"
+ "/run/initramfs/run\0";
+
+ const char *dir;
+
+ if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0) {
+ log_error("Failed to mount bind /run/initramfs on /run/initramfs: %m");
+ return -errno;
+ }
+
+ if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0) {
+ log_error("Failed to make /run/initramfs private mount: %m");
+ return -errno;
+ }
+
+ NULSTR_FOREACH(dir, dirs)
+ if (mkdir_p_label(dir, 0755) < 0 && errno != EEXIST) {
+ log_error("Failed to mkdir %s: %m", dir);
+ return -errno;
+ }
+
+ if (mount("/sys", "/run/initramfs/sys", NULL, MS_BIND, NULL) < 0) {
+ log_error("Failed to mount bind /sys on /run/initramfs/sys: %m");
+ return -errno;
+ }
+
+ if (mount("/proc", "/run/initramfs/proc", NULL, MS_BIND, NULL) < 0) {
+ log_error("Failed to mount bind /proc on /run/initramfs/proc: %m");
+ return -errno;
+ }
+
+ if (mount("/dev", "/run/initramfs/dev", NULL, MS_BIND, NULL) < 0) {
+ log_error("Failed to mount bind /dev on /run/initramfs/dev: %m");
+ return -errno;
+ }
+
+ if (mount("/run", "/run/initramfs/run", NULL, MS_BIND, NULL) < 0) {
+ log_error("Failed to mount bind /run on /run/initramfs/run: %m");
+ return -errno;
+ }
+
+ return 0;
+}
+
+static int pivot_to_new_root(void) {
+
+ if (chdir("/run/initramfs") < 0) {
+ log_error("Failed to change directory to /run/initramfs: %m");
+ return -errno;
+ }
+
+ /* Work-around for a kernel bug: for some reason the kernel
+ * refuses switching root if any file systems are mounted
+ * MS_SHARED. Hence remount them MS_PRIVATE here as a
+ * work-around.
+ *
+ * https://bugzilla.redhat.com/show_bug.cgi?id=847418 */
+ if (mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) < 0)
+ log_warning("Failed to make \"/\" private mount: %m");
+
+ if (pivot_root(".", "oldroot") < 0) {
+ log_error("pivot failed: %m");
+ /* only chroot if pivot root succeeded */
+ return -errno;
+ }
+
+ chroot(".");
+
+ setsid();
+ make_console_stdio();
+
+ log_info("Successfully changed into root pivot.");
+
+ return 0;
+}
+
+int main(int argc, char *argv[]) {
+ int cmd, r;
+ unsigned retries;
+ bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true;
+ bool in_container, use_watchdog = false;
+ char *arguments[3];
+
+ log_parse_environment();
+ log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */
+ log_open();
+
+ umask(0022);
+
+ if (getpid() != 1) {
+ log_error("Not executed by init (pid 1).");
+ r = -EPERM;
+ goto error;
+ }
+
+ if (argc != 2) {
+ log_error("Invalid number of arguments.");
+ r = -EINVAL;
+ goto error;
+ }
+
+ in_container = detect_container(NULL) > 0;
+
+ if (streq(argv[1], "reboot"))
+ cmd = RB_AUTOBOOT;
+ else if (streq(argv[1], "poweroff"))
+ cmd = RB_POWER_OFF;
+ else if (streq(argv[1], "halt"))
+ cmd = RB_HALT_SYSTEM;
+ else if (streq(argv[1], "kexec"))
+ cmd = LINUX_REBOOT_CMD_KEXEC;
+ else {
+ log_error("Unknown action '%s'.", argv[1]);
+ r = -EINVAL;
+ goto error;
+ }
+
+ use_watchdog = !!getenv("WATCHDOG_USEC");
+
+ /* lock us into memory */
+ mlockall(MCL_CURRENT|MCL_FUTURE);
+
+ log_info("Sending SIGTERM to remaining processes...");
+ broadcast_signal(SIGTERM, true);
+
+ log_info("Sending SIGKILL to remaining processes...");
+ broadcast_signal(SIGKILL, true);
+
+ if (in_container) {
+ need_swapoff = false;
+ need_dm_detach = false;
+ need_loop_detach = false;
+ }
+
+ /* Unmount all mountpoints, swaps, and loopback devices */
+ for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) {
+ bool changed = false;
+
+ if (use_watchdog)
+ watchdog_ping();
+
+ if (need_umount) {
+ log_info("Unmounting file systems.");
+ r = umount_all(&changed);
+ if (r == 0)
+ need_umount = false;
+ else if (r > 0)
+ log_info("Not all file systems unmounted, %d left.", r);
+ else
+ log_error("Failed to unmount file systems: %s", strerror(-r));
+ }
+
+ if (need_swapoff) {
+ log_info("Disabling swaps.");
+ r = swapoff_all(&changed);
+ if (r == 0)
+ need_swapoff = false;
+ else if (r > 0)
+ log_info("Not all swaps are turned off, %d left.", r);
+ else
+ log_error("Failed to turn off swaps: %s", strerror(-r));
+ }
+
+ if (need_loop_detach) {
+ log_info("Detaching loop devices.");
+ r = loopback_detach_all(&changed);
+ if (r == 0)
+ need_loop_detach = false;
+ else if (r > 0)
+ log_info("Not all loop devices detached, %d left.", r);
+ else
+ log_error("Failed to detach loop devices: %s", strerror(-r));
+ }
+
+ if (need_dm_detach) {
+ log_info("Detaching DM devices.");
+ r = dm_detach_all(&changed);
+ if (r == 0)
+ need_dm_detach = false;
+ else if (r > 0)
+ log_warning("Not all DM devices detached, %d left.", r);
+ else
+ log_error("Failed to detach DM devices: %s", strerror(-r));
+ }
+
+ if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach) {
+ if (retries > 0)
+ log_info("All filesystems, swaps, loop devices, DM devices detached.");
+ /* Yay, done */
+ break;
+ }
+
+ /* If in this iteration we didn't manage to
+ * unmount/deactivate anything, we simply give up */
+ if (!changed) {
+ log_error("Cannot finalize remaining file systems and devices, giving up.");
+ break;
+ }
+
+ log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1);
+ }
+
+ if (retries >= FINALIZE_ATTEMPTS)
+ log_error("Too many iterations, giving up.");
+
+ arguments[0] = NULL;
+ arguments[1] = argv[1];
+ arguments[2] = NULL;
+ execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, arguments);
+
+ if (!in_container &&
+ access("/run/initramfs/shutdown", X_OK) == 0) {
+
+ if (prepare_new_root() >= 0 &&
+ pivot_to_new_root() >= 0) {
+ execv("/shutdown", argv);
+ log_error("Failed to execute shutdown binary: %m");
+ }
+ }
+
+ if (cmd == LINUX_REBOOT_CMD_KEXEC) {
+
+ if (!in_container) {
+ /* We cheat and exec kexec to avoid doing all its work */
+ pid_t pid = fork();
+
+ if (pid < 0)
+ log_error("Could not fork: %m. Falling back to normal reboot.");
+ else if (pid > 0) {
+ wait_for_terminate_and_warn("kexec", pid);
+ log_warning("kexec failed. Falling back to normal reboot.");
+ } else {
+ /* Child */
+ const char *args[3] = { "/sbin/kexec", "-e", NULL };
+ execv(args[0], (char * const *) args);
+ return EXIT_FAILURE;
+ }
+ }
+
+ cmd = RB_AUTOBOOT;
+ }
+
+ reboot(cmd);
+
+ if (errno == EPERM && in_container) {
+ /* If we are in a container, and we lacked
+ * CAP_SYS_BOOT just exit, this will kill our
+ * container for good. */
+ log_error("Exiting container.");
+ exit(0);
+ }
+
+ log_error("Failed to invoke reboot(): %m");
+ r = -errno;
+
+ error:
+ log_error("Critical error while doing system shutdown: %s", strerror(-r));
+
+ freeze();
+ return EXIT_FAILURE;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-07 03:18:54 +0000