diff options
| -rw-r--r-- | Makefile.am | 17 | ||||
| -rw-r--r-- | src/shutdown.c | 345 |
2 files changed, 362 insertions, 0 deletions
diff --git a/Makefile.am b/Makefile.am index 4b248c0fc5..a79e94e893 100644 --- a/Makefile.am +++ b/Makefile.am @@ -35,6 +35,7 @@ tmpfilesdir=$(sysconfdir)/tmpfiles.d # And these are the special ones for / rootdir=@rootdir@ rootbindir=$(rootdir)/bin +rootsbindir=$(rootdir)/sbin rootlibexecdir=$(rootdir)/lib/systemd systemunitdir=$(rootdir)/lib/systemd/system @@ -50,9 +51,11 @@ AM_CPPFLAGS = \ -DSESSION_DATA_UNIT_PATH=\"$(sessionunitdir)\" \ -DCGROUP_AGENT_PATH=\"$(rootlibexecdir)/systemd-cgroups-agent\" \ -DSYSTEMD_BINARY_PATH=\"$(rootbindir)/systemd\" \ + -DSYSTEMD_SHUTDOWN_BINARY_PATH=\"$(rootlibexecdir)/systemd-shutdown\" \ -DSYSTEMCTL_BINARY_PATH=\"$(rootbindir)/systemctl\" \ -DRUNTIME_DIR=\"$(localstatedir)/run\" \ -DRANDOM_SEED=\"$(localstatedir)/lib/random-seed\" \ + -DKEXEC_BINARY_PATH=\"$(rootsbindir)/kexec\" \ -I $(top_srcdir)/src if TARGET_GENTOO @@ -96,6 +99,7 @@ rootlibexec_PROGRAMS = \ systemd-update-utmp \ systemd-random-seed \ systemd-shutdownd \ + systemd-shutdown \ systemd-modules-load \ systemd-remount-api-vfs \ systemd-kmsg-syslogd \ @@ -639,6 +643,19 @@ systemd_shutdownd_CFLAGS = \ systemd_shutdownd_LDADD = \ libsystemd-basic.la +systemd_shutdown_SOURCES = \ + src/mount-setup.c \ + src/umount.c \ + src/shutdown.c + +systemd_shutdown_CFLAGS = \ + $(AM_CFLAGS) \ + $(UDEV_CFLAGS) + +systemd_shutdown_LDADD = \ + libsystemd-basic.la \ + $(UDEV_LIBS) + systemd_modules_load_SOURCES = \ src/modules-load.c diff --git a/src/shutdown.c b/src/shutdown.c new file mode 100644 index 0000000000..023648c4cf --- /dev/null +++ b/src/shutdown.c @@ -0,0 +1,345 @@ +/*-*- 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 General Public License as published by + the Free Software Foundation; either version 2 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 + General Public License for more details. + + You should have received a copy of the GNU 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 <dirent.h> +#include <errno.h> +#include <unistd.h> +#include <signal.h> +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> + +#include "log.h" +#include "umount.h" +#include "util.h" + +#define TIMEOUT_USEC (5 * USEC_PER_SEC) +#define FINALIZE_ATTEMPTS 50 +#define FINALIZE_CRITICAL_ATTEMPTS 10 + +_noreturn_ static void freeze(void) { + for (;;) + pause(); +} + +static bool ignore_proc(pid_t pid) { + if (pid == 1) + return true; + + /* TODO: add more ignore rules here: device-mapper, etc */ + + return false; +} + +static bool is_kernel_thread(pid_t pid) +{ + char buf[PATH_MAX]; + FILE *f; + char c; + size_t count; + + snprintf(buf, sizeof(buf), "/proc/%lu/cmdline", (unsigned long)pid); + f = fopen(buf, "re"); + if (!f) + return true; /* not really, but has the desired effect */ + + count = fread(&c, 1, 1, f); + fclose(f); + return count != 1; +} + +static int killall(int sign) { + DIR *dir; + struct dirent *d; + unsigned int processes = 0; + + if ((dir = opendir("/proc")) == NULL) + return -errno; + + while ((d = readdir(dir))) { + pid_t pid; + + if (parse_pid(d->d_name, &pid) < 0) + continue; + + if (is_kernel_thread(pid)) + continue; + + if (ignore_proc(pid)) + continue; + + if (kill(pid, sign) == 0) + processes++; + else + log_warning("Could not kill %d: %m", pid); + } + + closedir(dir); + + return processes; +} + +static int send_signal(int sign) { + sigset_t mask, oldmask; + usec_t until; + int processes; + struct timespec ts; + + assert_se(sigemptyset(&mask) == 0); + assert_se(sigaddset(&mask, SIGCHLD) == 0); + if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) + return -errno; + + if (kill(-1, SIGSTOP) < 0) + log_warning("Failed kill(-1, SIGSTOP): %m"); + + processes = killall(sign); + + if (kill(-1, SIGCONT) < 0) + log_warning("Failed kill(-1, SIGCONT): %m"); + + if (processes <= 0) + goto finish; + + until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; + for (;;) { + usec_t n = now(CLOCK_MONOTONIC); + for (;;) { + pid_t pid = waitpid(-1, NULL, WNOHANG); + if (pid == 0) + break; + else if (pid < 0 && errno == ECHILD) { + processes = 0; + goto finish; + } + + if (--processes == 0) + goto finish; + } + + if (n >= until) + goto finish; + + timespec_store(&ts, until - n); + if (sigtimedwait(&mask, NULL, &ts) != SIGCHLD) + log_warning("Failed: sigtimedwait did not return SIGCHLD: %m"); + } + +finish: + sigprocmask(SIG_SETMASK, &oldmask, NULL); + + return processes; +} + +static int rescue_send_signal(int sign) { + sigset_t mask, oldmask; + usec_t until; + struct timespec ts; + int r; + + sigemptyset(&mask); + sigaddset(&mask, SIGCHLD); + if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) + return -errno; + + if (kill(-1, SIGSTOP) < 0) + log_warning("Failed kill(-1, SIGSTOP): %m"); + + r = kill(-1, sign); + if (r < 0) + log_warning("Failed kill(-1, %d): %m", sign); + + if (kill(-1, SIGCONT) < 0) + log_warning("Failed kill(-1, SIGCONT): %m"); + + if (r < 0) + goto finish; + + until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; + for (;;) { + usec_t n = now(CLOCK_MONOTONIC); + for (;;) { + pid_t pid = waitpid(-1, NULL, WNOHANG); + if (pid == 0) + break; + else if (pid < 0 && errno == ECHILD) + goto finish; + } + + if (n >= until) + goto finish; + + timespec_store(&ts, until - n); + if (sigtimedwait(&mask, NULL, &ts) != SIGCHLD) + log_warning("Failed: sigtimedwait did not return SIGCHLD: %m"); + } + +finish: + sigprocmask(SIG_SETMASK, &oldmask, NULL); + + return r; +} + + +int main(int argc, char *argv[]) { + int cmd, r, retries; + bool need_umount = true, need_swapoff = true, need_loop_detach = true; + + log_parse_environment(); + log_set_target(LOG_TARGET_KMSG); /* syslog will die if not gone yet */ + log_open(); + + 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; + } + + 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; + } + + /* lock us into memory */ + if (mlockall(MCL_CURRENT|MCL_FUTURE) != 0) + log_warning("Cannot lock process memory: %m"); + + log_info("Sending SIGTERM to processes"); + r = send_signal(SIGTERM); + if (r < 0) + log_warning("Cannot send SIGTERM to all process: %s", strerror(r)); + + log_info("Sending SIGKILL to processes"); + r = send_signal(SIGKILL); + if (r < 0) + log_warning("Cannot send SIGKILL to all process: %s", strerror(r)); + + + /* preventing that we won't block umounts */ + if (chdir("/") != 0) + log_warning("Cannot chdir(\"/\"): %m. Unmounts likely to fail."); + + /* umount all mountpoints, swaps, and loopback devices */ + retries = FINALIZE_ATTEMPTS; + while (need_umount || need_swapoff || need_loop_detach) { + if (need_umount) { + log_info("Unmounting filesystems."); + r = umount_all(); + if (r == 0) + need_umount = false; + else if (r > 0) + log_warning("Not all filesystems unmounted, %d left.", r); + else + log_error("Error unmounting filesystems: %s", strerror(-r)); + } + + if (need_swapoff) { + log_info("Disabling swaps."); + r = swapoff_all(); + if (r == 0) + need_swapoff = false; + else if (r > 0) + log_warning("Not all swaps are off, %d left.", r); + else + log_error("Error turning off swaps: %s", strerror(-r)); + } + + if (need_loop_detach) { + log_info("Detaching loop devices."); + r = loopback_detach_all(); + if (r == 0) + need_loop_detach = false; + else if (r > 0) + log_warning("Not all loop devices detached, %d left.", r); + else + log_error("Error detaching loop devices: %s", strerror(-r)); + + } + + if (need_umount || need_swapoff || need_loop_detach) { + retries--; + + if (retries <= FINALIZE_CRITICAL_ATTEMPTS) { + log_warning("Approaching critical level to finalize filesystem and devices, try to kill all processes."); + rescue_send_signal(SIGTERM); + rescue_send_signal(SIGKILL); + } + + if (retries > 0) + log_info("Action still required, %d tries left", retries); + else { + log_error("Tried enough but still action required need_umount=%d, need_swapoff=%d, need_loop_detach=%d", need_umount, need_swapoff, need_loop_detach); + r = -EBUSY; + goto error; + } + } + } + + sync(); + + if (cmd == LINUX_REBOOT_CMD_KEXEC) { + /* 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 reboot."); + cmd = RB_AUTOBOOT; + } else if (pid > 0) { + waitpid(pid, NULL, 0); + log_warning("Failed %s -e -x -f. Falling back to reboot", KEXEC_BINARY_PATH); + cmd = RB_AUTOBOOT; + } else { + const char *args[5] = {KEXEC_BINARY_PATH, "-e", "-f", "-x", NULL}; + execv(args[0], (char * const *) args); + return EXIT_FAILURE; + } + } + + reboot(cmd); + r = errno; + + error: + sync(); + if (r < 0) + r = -r; + log_error("Critical error while doing system shutdown: %s", strerror(r)); + freeze(); + return 0; +} |