Systemd/src/shutdown/shutdown.c
Hubert Kario 0b220a5f2a Try stopping MD RAID devices in shutdown too
Currently the systemd-shutdown command attempts to stop swaps, DM
(crypt, LVM2) and loop devices, but it doesn't attempt to stop MD
RAID devices, which means that if the RAID is set up on crypt,
loop, etc. device, it won't be able to stop those underlying devices.

This code extends the shutdown application to also attempt stopping
the MD RAID devices.

Signed-off-by: Hubert Kario <hubert@kario.pl>
2020-09-22 10:41:59 +02:00

626 lines
24 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
Copyright © 2010 ProFUSION embedded systems
***/
#include <errno.h>
#include <getopt.h>
#include <linux/reboot.h>
#include <stdbool.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/reboot.h>
#include <sys/stat.h>
#include <unistd.h>
#include "alloc-util.h"
#include "async.h"
#include "binfmt-util.h"
#include "cgroup-setup.h"
#include "cgroup-util.h"
#include "def.h"
#include "exec-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "killall.h"
#include "log.h"
#include "parse-util.h"
#include "process-util.h"
#include "reboot-util.h"
#include "rlimit-util.h"
#include "signal-util.h"
#include "string-util.h"
#include "switch-root.h"
#include "sysctl-util.h"
#include "terminal-util.h"
#include "umount.h"
#include "util.h"
#include "virt.h"
#include "watchdog.h"
#define SYNC_PROGRESS_ATTEMPTS 3
#define SYNC_TIMEOUT_USEC (10*USEC_PER_SEC)
static char* arg_verb;
static uint8_t arg_exit_code;
static usec_t arg_timeout = DEFAULT_TIMEOUT_USEC;
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_LOG_LEVEL = 0x100,
ARG_LOG_TARGET,
ARG_LOG_COLOR,
ARG_LOG_LOCATION,
ARG_LOG_TIME,
ARG_EXIT_CODE,
ARG_TIMEOUT,
};
static const struct option options[] = {
{ "log-level", required_argument, NULL, ARG_LOG_LEVEL },
{ "log-target", required_argument, NULL, ARG_LOG_TARGET },
{ "log-color", optional_argument, NULL, ARG_LOG_COLOR },
{ "log-location", optional_argument, NULL, ARG_LOG_LOCATION },
{ "log-time", optional_argument, NULL, ARG_LOG_TIME },
{ "exit-code", required_argument, NULL, ARG_EXIT_CODE },
{ "timeout", required_argument, NULL, ARG_TIMEOUT },
{}
};
int c, r;
assert(argc >= 1);
assert(argv);
/* "-" prevents getopt from permuting argv[] and moving the verb away
* from argv[1]. Our interface to initrd promises it'll be there. */
while ((c = getopt_long(argc, argv, "-", options, NULL)) >= 0)
switch (c) {
case ARG_LOG_LEVEL:
r = log_set_max_level_from_string(optarg);
if (r < 0)
log_error_errno(r, "Failed to parse log level %s, ignoring: %m", optarg);
break;
case ARG_LOG_TARGET:
r = log_set_target_from_string(optarg);
if (r < 0)
log_error_errno(r, "Failed to parse log target %s, ignoring: %m", optarg);
break;
case ARG_LOG_COLOR:
if (optarg) {
r = log_show_color_from_string(optarg);
if (r < 0)
log_error_errno(r, "Failed to parse log color setting %s, ignoring: %m", optarg);
} else
log_show_color(true);
break;
case ARG_LOG_LOCATION:
if (optarg) {
r = log_show_location_from_string(optarg);
if (r < 0)
log_error_errno(r, "Failed to parse log location setting %s, ignoring: %m", optarg);
} else
log_show_location(true);
break;
case ARG_LOG_TIME:
if (optarg) {
r = log_show_time_from_string(optarg);
if (r < 0)
log_error_errno(r, "Failed to parse log time setting %s, ignoring: %m", optarg);
} else
log_show_time(true);
break;
case ARG_EXIT_CODE:
r = safe_atou8(optarg, &arg_exit_code);
if (r < 0)
log_error_errno(r, "Failed to parse exit code %s, ignoring: %m", optarg);
break;
case ARG_TIMEOUT:
r = parse_sec(optarg, &arg_timeout);
if (r < 0)
log_error_errno(r, "Failed to parse shutdown timeout %s, ignoring: %m", optarg);
break;
case '\001':
if (!arg_verb)
arg_verb = optarg;
else
log_error("Excess arguments, ignoring");
break;
case '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option code.");
}
if (!arg_verb)
return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
"Verb argument missing.");
return 0;
}
static int switch_root_initramfs(void) {
if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0)
return log_error_errno(errno, "Failed to mount bind /run/initramfs on /run/initramfs: %m");
if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0)
return log_error_errno(errno, "Failed to make /run/initramfs private mount: %m");
/* switch_root with MS_BIND, because there might still be processes lurking around, which have open file descriptors.
* /run/initramfs/shutdown will take care of these.
* Also do not detach the old root, because /run/initramfs/shutdown needs to access it.
*/
return switch_root("/run/initramfs", "/oldroot", false, MS_BIND);
}
/* Read the following fields from /proc/meminfo:
*
* NFS_Unstable
* Writeback
* Dirty
*
* Return true if the sum of these fields is greater than the previous
* value input. For all other issues, report the failure and indicate that
* the sync is not making progress.
*/
static int sync_making_progress(unsigned long long *prev_dirty) {
_cleanup_fclose_ FILE *f = NULL;
unsigned long long val = 0;
int ret;
f = fopen("/proc/meminfo", "re");
if (!f)
return log_warning_errno(errno, "Failed to open /proc/meminfo: %m");
for (;;) {
_cleanup_free_ char *line = NULL;
unsigned long long ull = 0;
int q;
q = read_line(f, LONG_LINE_MAX, &line);
if (q < 0)
return log_warning_errno(q, "Failed to parse /proc/meminfo: %m");
if (q == 0)
break;
if (!first_word(line, "NFS_Unstable:") && !first_word(line, "Writeback:") && !first_word(line, "Dirty:"))
continue;
errno = 0;
if (sscanf(line, "%*s %llu %*s", &ull) != 1) {
if (errno != 0)
log_warning_errno(errno, "Failed to parse /proc/meminfo: %m");
else
log_warning("Failed to parse /proc/meminfo");
return false;
}
val += ull;
}
ret = *prev_dirty > val;
*prev_dirty = val;
return ret;
}
static void sync_with_progress(void) {
unsigned long long dirty = ULLONG_MAX;
unsigned checks;
pid_t pid;
int r;
BLOCK_SIGNALS(SIGCHLD);
/* Due to the possibility of the sync operation hanging, we fork a child process and monitor the progress. If
* the timeout lapses, the assumption is that that particular sync stalled. */
r = asynchronous_sync(&pid);
if (r < 0) {
log_error_errno(r, "Failed to fork sync(): %m");
return;
}
log_info("Syncing filesystems and block devices.");
/* Start monitoring the sync operation. If more than
* SYNC_PROGRESS_ATTEMPTS lapse without progress being made,
* we assume that the sync is stalled */
for (checks = 0; checks < SYNC_PROGRESS_ATTEMPTS; checks++) {
r = wait_for_terminate_with_timeout(pid, SYNC_TIMEOUT_USEC);
if (r == 0)
/* Sync finished without error.
* (The sync itself does not return an error code) */
return;
else if (r == -ETIMEDOUT) {
/* Reset the check counter if the "Dirty" value is
* decreasing */
if (sync_making_progress(&dirty) > 0)
checks = 0;
} else {
log_error_errno(r, "Failed to sync filesystems and block devices: %m");
return;
}
}
/* Only reached in the event of a timeout. We should issue a kill
* to the stray process. */
log_error("Syncing filesystems and block devices - timed out, issuing SIGKILL to PID "PID_FMT".", pid);
(void) kill(pid, SIGKILL);
}
static int read_current_sysctl_printk_log_level(void) {
_cleanup_free_ char *sysctl_printk_vals = NULL, *sysctl_printk_curr = NULL;
int current_lvl;
const char *p;
int r;
r = sysctl_read("kernel/printk", &sysctl_printk_vals);
if (r < 0)
return log_debug_errno(r, "Cannot read sysctl kernel.printk: %m");
p = sysctl_printk_vals;
r = extract_first_word(&p, &sysctl_printk_curr, NULL, 0);
if (r < 0)
return log_debug_errno(r, "Failed to split out kernel printk priority: %m");
if (r == 0)
return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Short read while reading kernel.printk sysctl");
r = safe_atoi(sysctl_printk_curr, &current_lvl);
if (r < 0)
return log_debug_errno(r, "Failed to parse kernel.printk sysctl: %s", sysctl_printk_vals);
return current_lvl;
}
static void bump_sysctl_printk_log_level(int min_level) {
int current_lvl, r;
/* Set the logging level to be able to see messages with log level smaller or equal to min_level */
current_lvl = read_current_sysctl_printk_log_level();
if (current_lvl < 0 || current_lvl >= min_level + 1)
return;
r = sysctl_writef("kernel/printk", "%i", min_level + 1);
if (r < 0)
log_debug_errno(r, "Failed to bump kernel.printk to %i: %m", min_level + 1);
}
int main(int argc, char *argv[]) {
bool need_umount, need_swapoff, need_loop_detach, need_dm_detach, need_md_detach, in_container, use_watchdog = false, can_initrd;
_cleanup_free_ char *cgroup = NULL;
char *arguments[3], *watchdog_device;
int cmd, r, umount_log_level = LOG_INFO;
static const char* const dirs[] = {SYSTEM_SHUTDOWN_PATH, NULL};
/* The log target defaults to console, but the original systemd process will pass its log target in through a
* command line argument, which will override this default. Also, ensure we'll never log to the journal or
* syslog, as these logging daemons are either already dead or will die very soon. */
log_set_target(LOG_TARGET_CONSOLE);
log_set_prohibit_ipc(true);
log_parse_environment();
r = parse_argv(argc, argv);
if (r < 0)
goto error;
log_open();
umask(0022);
if (getpid_cached() != 1) {
log_error("Not executed by init (PID 1).");
r = -EPERM;
goto error;
}
if (streq(arg_verb, "reboot"))
cmd = RB_AUTOBOOT;
else if (streq(arg_verb, "poweroff"))
cmd = RB_POWER_OFF;
else if (streq(arg_verb, "halt"))
cmd = RB_HALT_SYSTEM;
else if (streq(arg_verb, "kexec"))
cmd = LINUX_REBOOT_CMD_KEXEC;
else if (streq(arg_verb, "exit"))
cmd = 0; /* ignored, just checking that arg_verb is valid */
else {
log_error("Unknown action '%s'.", arg_verb);
r = -EINVAL;
goto error;
}
(void) cg_get_root_path(&cgroup);
in_container = detect_container() > 0;
/* If the logging messages are going to KMSG, and if we are not running from a container, then try to
* update the sysctl kernel.printk current value in order to see "info" messages; This current log
* level is not updated if already big enough.
*/
if (!in_container &&
IN_SET(log_get_target(),
LOG_TARGET_AUTO,
LOG_TARGET_JOURNAL_OR_KMSG,
LOG_TARGET_SYSLOG_OR_KMSG,
LOG_TARGET_KMSG))
bump_sysctl_printk_log_level(LOG_WARNING);
use_watchdog = getenv("WATCHDOG_USEC");
watchdog_device = getenv("WATCHDOG_DEVICE");
if (watchdog_device) {
r = watchdog_set_device(watchdog_device);
if (r < 0)
log_warning_errno(r, "Failed to set watchdog device to %s, ignoring: %m",
watchdog_device);
}
/* Lock us into memory */
(void) mlockall(MCL_CURRENT|MCL_FUTURE);
/* Synchronize everything that is not written to disk yet at this point already. This is a good idea so that
* slow IO is processed here already and the final process killing spree is not impacted by processes
* desperately trying to sync IO to disk within their timeout. Do not remove this sync, data corruption will
* result. */
if (!in_container)
sync_with_progress();
disable_coredumps();
disable_binfmt();
log_info("Sending SIGTERM to remaining processes...");
broadcast_signal(SIGTERM, true, true, arg_timeout);
log_info("Sending SIGKILL to remaining processes...");
broadcast_signal(SIGKILL, true, false, arg_timeout);
need_umount = !in_container;
need_swapoff = !in_container;
need_loop_detach = !in_container;
need_dm_detach = !in_container;
need_md_detach = !in_container;
can_initrd = !in_container && !in_initrd() && access("/run/initramfs/shutdown", X_OK) == 0;
/* Unmount all mountpoints, swaps, and loopback devices */
for (;;) {
bool changed = false;
if (use_watchdog)
(void) watchdog_ping();
/* Let's trim the cgroup tree on each iteration so
that we leave an empty cgroup tree around, so that
container managers get a nice notify event when we
are down */
if (cgroup)
(void) cg_trim(SYSTEMD_CGROUP_CONTROLLER, cgroup, false);
if (need_umount) {
log_info("Unmounting file systems.");
r = umount_all(&changed, umount_log_level);
if (r == 0) {
need_umount = false;
log_info("All filesystems unmounted.");
} else if (r > 0)
log_info("Not all file systems unmounted, %d left.", r);
else
log_error_errno(r, "Failed to unmount file systems: %m");
}
if (need_swapoff) {
log_info("Deactivating swaps.");
r = swapoff_all(&changed);
if (r == 0) {
need_swapoff = false;
log_info("All swaps deactivated.");
} else if (r > 0)
log_info("Not all swaps deactivated, %d left.", r);
else
log_error_errno(r, "Failed to deactivate swaps: %m");
}
if (need_loop_detach) {
log_info("Detaching loop devices.");
r = loopback_detach_all(&changed, umount_log_level);
if (r == 0) {
need_loop_detach = false;
log_info("All loop devices detached.");
} else if (r > 0)
log_info("Not all loop devices detached, %d left.", r);
else
log_error_errno(r, "Failed to detach loop devices: %m");
}
if (need_md_detach) {
log_info("Stopping MD devices.");
r = md_detach_all(&changed, umount_log_level);
if (r == 0) {
need_md_detach = false;
log_info("All MD devices stopped.");
} else if (r > 0)
log_info("Not all MD devices stopped, %d left.", r);
else
log_error_errno(r, "Failed to stop MD devices: %m");
}
if (need_dm_detach) {
log_info("Detaching DM devices.");
r = dm_detach_all(&changed, umount_log_level);
if (r == 0) {
need_dm_detach = false;
log_info("All DM devices detached.");
} else if (r > 0)
log_info("Not all DM devices detached, %d left.", r);
else
log_error_errno(r, "Failed to detach DM devices: %m");
}
if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach
&& !need_md_detach) {
log_info("All filesystems, swaps, loop devices, MD devices and DM devices detached.");
/* Yay, done */
break;
}
if (!changed && umount_log_level == LOG_INFO && !can_initrd) {
/* There are things we cannot get rid of. Loop one more time
* with LOG_ERR to inform the user. Note that we don't need
* to do this if there is a initrd to switch to, because that
* one is likely to get rid of the remounting mounts. If not,
* it will log about them. */
umount_log_level = LOG_ERR;
continue;
}
/* If in this iteration we didn't manage to
* unmount/deactivate anything, we simply give up */
if (!changed) {
log_info("Cannot finalize remaining%s%s%s%s%s continuing.",
need_umount ? " file systems," : "",
need_swapoff ? " swap devices," : "",
need_loop_detach ? " loop devices," : "",
need_dm_detach ? " DM devices," : "",
need_md_detach ? " MD devices," : "");
break;
}
log_debug("Couldn't finalize remaining %s%s%s%s%s trying again.",
need_umount ? " file systems," : "",
need_swapoff ? " swap devices," : "",
need_loop_detach ? " loop devices," : "",
need_dm_detach ? " DM devices," : "",
need_md_detach ? " MD devices," : "");
}
/* We're done with the watchdog. */
watchdog_free_device();
arguments[0] = NULL;
arguments[1] = arg_verb;
arguments[2] = NULL;
(void) execute_directories(dirs, DEFAULT_TIMEOUT_USEC, NULL, NULL, arguments, NULL, EXEC_DIR_PARALLEL | EXEC_DIR_IGNORE_ERRORS);
(void) rlimit_nofile_safe();
if (can_initrd) {
r = switch_root_initramfs();
if (r >= 0) {
argv[0] = (char*) "/shutdown";
(void) setsid();
(void) make_console_stdio();
log_info("Successfully changed into root pivot.\n"
"Returning to initrd...");
execv("/shutdown", argv);
log_error_errno(errno, "Failed to execute shutdown binary: %m");
} else
log_error_errno(r, "Failed to switch root to \"/run/initramfs\": %m");
}
if (need_umount || need_swapoff || need_loop_detach || need_dm_detach || need_md_detach)
log_error("Failed to finalize%s%s%s%s%s ignoring.",
need_umount ? " file systems," : "",
need_swapoff ? " swap devices," : "",
need_loop_detach ? " loop devices," : "",
need_dm_detach ? " DM devices," : "",
need_md_detach ? " MD devices," : "");
/* The kernel will automatically flush ATA disks and suchlike on reboot(), but the file systems need to be
* sync'ed explicitly in advance. So let's do this here, but not needlessly slow down containers. Note that we
* sync'ed things already once above, but we did some more work since then which might have caused IO, hence
* let's do it once more. Do not remove this sync, data corruption will result. */
if (!in_container)
sync_with_progress();
if (streq(arg_verb, "exit")) {
if (in_container)
return arg_exit_code;
cmd = RB_POWER_OFF; /* We cannot exit() on the host, fallback on another method. */
}
switch (cmd) {
case LINUX_REBOOT_CMD_KEXEC:
if (!in_container) {
/* We cheat and exec kexec to avoid doing all its work */
log_info("Rebooting with kexec.");
r = safe_fork("(sd-kexec)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_LOG|FORK_WAIT, NULL);
if (r == 0) {
const char * const args[] = {
KEXEC, "-e", NULL
};
/* Child */
execv(args[0], (char * const *) args);
/* execv failed (kexec binary missing?), so try simply reboot(RB_KEXEC) */
(void) reboot(cmd);
_exit(EXIT_FAILURE);
}
/* If we are still running, then the kexec can't have worked, let's fall through */
}
cmd = RB_AUTOBOOT;
_fallthrough_;
case RB_AUTOBOOT:
(void) reboot_with_parameter(REBOOT_LOG);
log_info("Rebooting.");
break;
case RB_POWER_OFF:
log_info("Powering off.");
break;
case RB_HALT_SYSTEM:
log_info("Halting system.");
break;
default:
assert_not_reached("Unknown magic");
}
(void) 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_info("Exiting container.");
return EXIT_SUCCESS;
}
r = log_error_errno(errno, "Failed to invoke reboot(): %m");
error:
log_emergency_errno(r, "Critical error while doing system shutdown: %m");
freeze();
}