qubes-linux-utils/dracut/full-dmroot/qubes_cow_setup.sh
Marek Marczykowski-Górecki b227d01a8a
Fix initramfs scripts on Debian
1. /etc/udev/rules.d needs to be created
2. udev needs to be reloaded explicitly

Fixes QubesOS/qubes-issues#3178
2017-10-16 23:41:21 +02:00

110 lines
2.9 KiB
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#!/bin/sh
#
# This file should be placed in pre-trigger directory in dracut's initramfs, or
# scripts/local-top in case of initramfs-tools
#
# initramfs-tools (Debian) API
PREREQS=""
case "$1" in
prereqs)
# This runs during initramfs creation
echo "$PREREQS"
exit 0
;;
esac
# This runs inside real initramfs
if [ -r /scripts/functions ]; then
# We're running in Debian's initramfs
. /scripts/functions
alias die=panic
alias info=true
alias warn=log_warning_msg
alias log_begin=log_begin_msg
alias log_end=log_end_msg
elif [ -r /lib/dracut-lib.sh ]; then
. /lib/dracut-lib.sh
alias log_begin=info
alias log_end=true
else
die() {
echo "$@"
exit 1
}
alias info=echo
alias warn=echo
alias log_begin=echo
alias log_end=true
fi
info "Qubes initramfs script here:"
if ! grep -q 'root=[^ ]*dmroot' /proc/cmdline; then
warn "dmroot not requested, probably not a Qubes VM"
exit 0
fi
if [ -e /dev/mapper/dmroot ] ; then
die "Qubes: FATAL error: /dev/mapper/dmroot already exists?!"
fi
modprobe xenblk || modprobe xen-blkfront || warn "Qubes: Cannot load Xen Block Frontend..."
log_begin "Waiting for /dev/xvda* devices..."
while ! [ -e /dev/xvda ]; do sleep 0.1; done
log_end
# prefer first partition if exists
if [ -b /dev/xvda1 ]; then
ROOT_DEV=xvda1
else
ROOT_DEV=xvda
fi
SWAP_SIZE=$(( 1024 * 1024 * 2 )) # sectors, 1GB
if [ `cat /sys/class/block/$ROOT_DEV/ro` = 1 ] ; then
log_begin "Qubes: Doing COW setup for AppVM..."
while ! [ -e /dev/xvdc ]; do sleep 0.1; done
VOLATILE_SIZE=$(cat /sys/class/block/xvdc/size) # sectors
ROOT_SIZE=$(cat /sys/class/block/$ROOT_DEV/size) # sectors
if [ $VOLATILE_SIZE -lt $SWAP_SIZE ]; then
die "volatile.img smaller than 1GB, cannot continue"
fi
sfdisk -q --unit S /dev/xvdc >/dev/null <<EOF
1,$SWAP_SIZE,S
,,L
EOF
if [ $? -ne 0 ]; then
die "Qubes: failed to setup partitions on volatile device"
fi
while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
mkswap /dev/xvdc1
while ! [ -e /dev/xvdc2 ]; do sleep 0.1; done
echo "0 `cat /sys/class/block/$ROOT_DEV/size` snapshot /dev/$ROOT_DEV /dev/xvdc2 N 16" | \
dmsetup --noudevsync create dmroot || die "Qubes: FATAL: cannot create dmroot!"
dmsetup mknodes dmroot
log_end
else
log_begin "Qubes: Doing R/W setup for TemplateVM..."
while ! [ -e /dev/xvdc ]; do sleep 0.1; done
sfdisk -q --unit S /dev/xvdc >/dev/null <<EOF
1,$SWAP_SIZE,S
EOF
if [ $? -ne 0 ]; then
die "Qubes: failed to setup partitions on volatile device"
fi
while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
mkswap /dev/xvdc1
mkdir -p /etc/udev/rules.d
printf 'KERNEL=="%s", SYMLINK+="mapper/dmroot"\n' "$ROOT_DEV" >> \
/etc/udev/rules.d/99-root.rules
udevadm control -R
udevadm trigger
log_end
fi