[kexec-reboot] fast reboot via kexec

bound to ctrl-alt-del on ttys
TODO enable Xorg support

9 files changed, 124 insertions, 0 deletions

diff --git a/core/modules/kexec-reboot/data/etc/systemd/system/ctrl-alt-del.target b/core/modules/kexec-reboot/data/etc/systemd/system/ctrl-alt-del.target
new file mode 120000
index 00000000..b1da000b
--- /dev/null
+++ b/core/modules/kexec-reboot/data/etc/systemd/system/ctrl-alt-del.target
@@ -0,0 +1 @@
+kexec.target
\ No newline at end of file
diff --git a/core/modules/kexec-reboot/data/etc/systemd/system/kexec-load.service b/core/modules/kexec-reboot/data/etc/systemd/system/kexec-load.service
new file mode 100644
index 00000000..4fcebd66
--- /dev/null
+++ b/core/modules/kexec-reboot/data/etc/systemd/system/kexec-load.service
@@ -0,0 +1,12 @@
+[Unit]
+Description=Reload the kernel/initramfs via kexec
+Documentation=man:kexec(8)
+DefaultDependencies=no
+Before=shutdown.target final.target
+
+[Service]
+Type=oneshot
+ExecStart=/opt/openslx/scripts/systemd-kexec_load
+
+[Install]
+WantedBy=kexec.target
diff --git a/core/modules/kexec-reboot/data/etc/systemd/system/kexec.service b/core/modules/kexec-reboot/data/etc/systemd/system/kexec.service
new file mode 100644
index 00000000..45c117ad
--- /dev/null
+++ b/core/modules/kexec-reboot/data/etc/systemd/system/kexec.service
@@ -0,0 +1,15 @@
+[Unit]
+Description=Reboot via kexec
+Documentation=man:kexec(8)
+DefaultDependencies=no
+Wants=kexec-load.service
+After=kexec-load.service
+Requires=shutdown.target final.target
+Before=shutdown.target final.target
+
+[Service]
+Type=oneshot
+ExecStart=/opt/openslx/scripts/systemd-kexec_exec
+
+[Install]
+WantedBy=kexec.target
diff --git a/core/modules/kexec-reboot/data/etc/systemd/system/kexec.target b/core/modules/kexec-reboot/data/etc/systemd/system/kexec.target
new file mode 100644
index 00000000..5be5b8c5
--- /dev/null
+++ b/core/modules/kexec-reboot/data/etc/systemd/system/kexec.target
@@ -0,0 +1,19 @@
+#  SPDX-License-Identifier: LGPL-2.1+
+#
+#  This file is part of systemd.
+#
+#  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.
+
+[Unit]
+Description=Reboot via kexec
+Documentation=man:systemd.special(7)
+DefaultDependencies=no
+Requires=kexec.service
+After=kexec.service
+AllowIsolate=yes
+
+[Install]
+Alias=ctrl-alt-del.target
diff --git a/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_exec b/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_exec
new file mode 100755
index 00000000..d5ff3e57
--- /dev/null
+++ b/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_exec
@@ -0,0 +1,12 @@
+#!/bin/ash
+
+# check if kernel sees a preloaded kernel for kexec
+if which kexec 2>/dev/null && [ "x$(cat /sys/kernel/kexec_loaded)" = "x1" ]; then
+	kexec -e
+fi
+
+# enable sysrq and trigger reboot
+echo 1 > /proc/sys/kernel/sysrq
+echo b > /proc/sysrq-trigger
+
+# TODO start fbsplash or something
diff --git a/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_load b/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_load
new file mode 100755
index 00000000..ca092b3e
--- /dev/null
+++ b/core/modules/kexec-reboot/data/opt/openslx/scripts/systemd-kexec_load
@@ -0,0 +1,40 @@
+#!/bin/ash
+
+kexec=$(which kexec 2>/dev/null)
+if [ -z "$kexec" ]; then
+	echo "Failed to find kexec binary in PATH. Exiting."
+	exit 1
+fi
+
+# download_retry <url> <path>
+download_retry() {
+	[ $# -ne 2 ] && return 1
+	for TIMEOUT in 1 1 2 3 END; do
+		[ "x$TIMEOUT" = "xEND" ] && break
+		if wget -T 2 -O "$2" "$1"; then
+			return 0
+			break
+		fi
+		sleep $TIMEOUT
+	done
+	return 1
+}
+
+kexec_load() {
+	. /opt/openslx/config
+	local DIR="$(mktemp -d)"
+
+	for FILE in kernel initramfs-stage31; do
+		if ! download_retry "http://${SLX_KCL_SERVERS}/${SLX_BASE_PATH}/${FILE}" "${DIR}/${FILE}" ; then
+			echo "Failed to download ${FILE}."
+			exit 1
+		fi
+	done
+
+	if ! kexec -l "${DIR}/kernel" --initrd "${DIR}/initramfs-stage31" --reuse-cmdline; then
+		echo "Failed to load kernel/initrd from ${DIR}"
+		exit 1
+	fi
+}
+
+kexec_load
diff --git a/core/modules/kexec-reboot/module.build b/core/modules/kexec-reboot/module.build
new file mode 100644
index 00000000..fa7038b8
--- /dev/null
+++ b/core/modules/kexec-reboot/module.build
@@ -0,0 +1,19 @@
+#!/bin/bash
+fetch_source() {
+	:
+}
+
+build() {
+
+	local BIN_LOCATION="$(which kexec)"
+	[ ! -z "${BIN_LOCATION}" ] && BIN_LOCATION=$(readlink -f "$BIN_LOCATION")
+	if [ ! -z "${BIN_LOCATION}" -a -e "${BIN_LOCATION}" ]; then
+		tarcopy "${BIN_LOCATION}" "${MODULE_BUILD_DIR}"
+	else
+		perror "'kexec' not found on the system! Please install it."
+	fi
+}
+
+post_copy() {
+	:
+}
diff --git a/core/modules/kexec-reboot/module.conf b/core/modules/kexec-reboot/module.conf
new file mode 100644
index 00000000..d6ea23f4
--- /dev/null
+++ b/core/modules/kexec-reboot/module.conf
@@ -0,0 +1,3 @@
+REQUIRED_BINARIES="
+	kexec
+"
diff --git a/core/modules/kexec-reboot/module.conf.ubuntu b/core/modules/kexec-reboot/module.conf.ubuntu
new file mode 100644
index 00000000..efc88ea8
--- /dev/null
+++ b/core/modules/kexec-reboot/module.conf.ubuntu
@@ -0,0 +1,3 @@
+REQUIRED_INSTALLED_PACKAGES="
+	kexec-tools
+"