systemd/systemd-sleep-grub

205 lines
5.9 KiB
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#!/bin/bash
#
# Copyright (c) 2013 SUSE LINUX Products GmbH, Nuernberg, Germany.
set -x
prepare-parameters()
{
eval `grep LOADER_TYPE= /etc/sysconfig/bootloader`
if [ x"$LOADER_TYPE" = "xgrub2" -o x"$LOADER_TYPE" = "xgrub2-efi" ]; then
GRUBONCE="/usr/sbin/grub2-once"
GRUBDEFAULT="/boot/grub2/grubenv"
GRUB2EDITENV="/usr/bin/grub2-editenv"
GRUB2CONF="/boot/grub2/grub.cfg"
BLKID="/usr/sbin/blkid"
getkernels="getkernels-grub2"
fi
}
#####################################################################
# gets a list of available kernels from /boot/grub2/grub.cfg
# kernels are in the array $KERNELS, output to stdout to be eval-ed.
getkernels-grub2()
{
local I DUMMY MNT ROOTDEV
declare -i I=0 J=-1
# we need the root partition later to decide if this is the kernel to select
while read ROOTDEV MNT DUMMY; do
[ "$ROOTDEV" = "rootfs" ] && continue # not what we are searching for
if [ "$MNT" = "/" ]; then
break
fi
done < /proc/mounts
while read LINE; do
case $LINE in
menuentry\ *)
let J++
;;
set\ default*)
local DEFAULT=${LINE#*default=}
if echo $DEFAULT | grep -q saved_entry ; then
local SAVED=`$GRUB2EDITENV $GRUBDEFAULT list | sed -n s/^saved_entry=//p`
if [ -n "$SAVED" ]; then
DEFAULT_BOOT=$($GRUBONCE --show-mapped "$SAVED")
fi
fi
;;
linux*noresume*|module*xen*noresume*)
echo " Skipping grub entry #${J}, because it has the noresume option" >&2
;;
linux*root=*|module*xen*root=*)
local ROOT
ROOT=${LINE#*root=}
DUMMY=($ROOT)
ROOT=${DUMMY[0]}
if [ x"${ROOT:0:5}" = "xUUID=" ]; then
UUID=${ROOT#UUID=}
if [ -n "$UUID" ]; then
ROOT=$($BLKID -U $UUID)
fi
fi
if [ "$(stat -Lc '%t:%T' $ROOT)" != "$(stat -Lc '%t:%T' $ROOTDEV)" ]; then
echo " Skipping grub entry #${J}, because its root= parameter ($ROOT)" >&2
echo " does not match the current root device ($ROOTDEV)." >&2
continue
fi
DUMMY=($LINE) # kernel (hd0,1)/boot/vmlinuz-ABC root=/dev/hda2
echo "KERNELS[$I]='${DUMMY[1]##*/}'" # vmlinuz-ABC
echo "MENU_ENTRIES[$I]=$J"
# DEBUG "Found kernel entry #${I}: '${DUMMY[1]##*/}'" INFO
let I++
;;
linux*|module*xen*)
# a kernel without "root="? We better skip that one...
echo " Skipping grub entry #${J}, because it has no root= option" >&2
;;
*) ;;
esac
done < "$GRUB2CONF"
}
#############################################################
# runs grubonce from the grub package to select which kernel
# to boot on next startup
grub-once()
{
if [ -x "$GRUBONCE" ]; then
echo " running '$GRUBONCE $1'"
$GRUBONCE $1
else
echo "WARNING: $GRUBONCE not found, not preparing bootloader"
fi
}
#############################################################
# restore grub default after (eventually failed) resume
grub-once-restore()
{
echo "INFO: running grub-once-restore"
prepare-parameters
$GRUB2EDITENV $GRUBDEFAULT unset next_entry
}
#############################################################################
# try to find a kernel image that matches the actually running kernel.
# We need this, if more than one kernel is installed. This works reasonably
# well with grub, if all kernels are named "vmlinuz-`uname -r`" and are
# located in /boot. If they are not, good luck ;-)
find-kernel-entry()
{
NEXT_BOOT=-1
ARCH=`uname -m`
declare -i I=0
# DEBUG "running kernel: $RUNNING" DIAG
while [ -n "${KERNELS[$I]}" ]; do
BOOTING="${KERNELS[$I]}"
if IMAGE=`readlink /boot/$BOOTING` && [ -e "/boot/${IMAGE##*/}" ]; then
# DEBUG "Found kernel symlink $BOOTING => $IMAGE" INFO
BOOTING=$IMAGE
fi
case $ARCH in
ppc*) BOOTING="${BOOTING#*vmlinux-}" ;;
*) BOOTING="${BOOTING#*vmlinuz-}" ;;
esac
if [ "$RUNNING" == "$BOOTING" ]; then
NEXT_BOOT=${MENU_ENTRIES[$I]}
echo " running kernel is grub menu entry $NEXT_BOOT (${KERNELS[$I]})"
break
fi
let I++
done
# if we have not found a kernel, issue a warning.
# if we have found a kernel, we'll do "grub-once" later, after
# prepare_suspend finished.
if [ $NEXT_BOOT -eq -1 ]; then
echo "WARNING: no kernelfile matching the running kernel found"
fi
}
#############################################################################
# if we did not find a kernel (or BOOT_LOADER is not GRUB) check,
# if the running kernel is still the one that will (probably) be booted for
# resume (default entry in menu.lst or, if there is none, the kernel file
# /boot/vmlinuz points to.)
# This will only work, if you use "original" SUSE kernels.
# you can always override with the config variable set to "yes"
prepare-grub()
{
echo "INFO: running prepare-grub"
prepare-parameters
eval `$getkernels`
RUNNING=`uname -r`
find-kernel-entry
RET=0
if [ $NEXT_BOOT -eq -1 ]; then
# which kernel is booted with the default entry?
BOOTING="${KERNELS[$DEFAULT_BOOT]}"
# if there is no default entry (no menu.lst?) we fall back to
# the default of /boot/vmlinuz.
[ -z "$BOOTING" ] && BOOTING="vmlinuz"
if IMAGE=`readlink /boot/$BOOTING` && [ -e "/boot/${IMAGE##*/}" ]; then
BOOTING=$IMAGE
fi
BOOTING="${BOOTING#*vmlinuz-}"
echo "running kernel: '$RUNNING', probably booting kernel: '$BOOTING'"
if [ "$BOOTING" != "$RUNNING" ]; then
echo "ERROR: kernel version mismatch, cannot suspend to disk"
echo "running: $RUNNING booting: $BOOTING" >> $INHIBIT
RET=1
fi
else
# set the bootloader to the running kernel
echo " preparing boot-loader: selecting entry $NEXT_BOOT, kernel /boot/$BOOTING"
T1=`date +"%s%N"`
sync; sync; sync # this is needed to speed up grub-once on reiserfs
T2=`date +"%s%N"`
echo " grub-once: `grub-once $NEXT_BOOT`"
T3=`date +"%s%N"`
S=$(((T2-T1)/100000000)); S="$((S/10)).${S:0-1}"
G=$(((T3-T2)/100000000)); G="$((G/10)).${G:0-1}"
echo " time needed for sync: $S seconds, time needed for grub: $G seconds."
fi
return $RET
}
###### main()
if [ "$1" = pre ] ; then
prepare-grub
fi
if [ "$1" = post ] ; then
grub-once-restore
fi