qubes-linux-utils/dracut/simple/init.sh
Marek Marczykowski-Górecki d0fe5e6f9a
initramfs: add support for root.img with partition table
Installing grub on root.img require some space before the filesystem.
Create it by adding partition table to root.img. This commit take care
of assembling dmroot device when such partition table is present, while
preserving compatibility with partition-less images.

QubesOS/qubes-issues#2577
2017-04-08 13:58:33 +02:00

109 lines
3.2 KiB
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#!/bin/sh
echo "Qubes initramfs script here:"
mkdir -p /proc /sys /dev
mount -t proc proc /proc
mount -t sysfs sysfs /sys
mount -t devtmpfs devtmpfs /dev
if [ -e /dev/mapper/dmroot ] ; then
echo "Qubes: FATAL error: /dev/mapper/dmroot already exists?!"
fi
modprobe xenblk || modprobe xen-blkfront || echo "Qubes: Cannot load Xen Block Frontend..."
die() {
echo "$@" >&2
exit 1
}
echo "Waiting for /dev/xvda* devices..."
while ! [ -e /dev/xvda ]; do sleep 0.1; done
# prefer first partition if exists
if [ -b /dev/xvda1 ]; then
ROOT_DEV=xvda1
else
ROOT_DEV=xvda
fi
SWAP_SIZE=$(( 1024 * 1024 * 2 )) # sectors, 1GB
if [ `cat /sys/class/block/$ROOT_DEV/ro` = 1 ] ; then
echo "Qubes: Doing COW setup for AppVM..."
while ! [ -e /dev/xvdc ]; do sleep 0.1; done
VOLATILE_SIZE=$(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 [ $? -ne 0 ]; then
echo "Qubes: failed to setup partitions on volatile device"
exit 1
fi
while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
mkswap /dev/xvdc1
while ! [ -e /dev/xvdc2 ]; do sleep 0.1; done
echo "0 `cat /sys/class/block/$ROOT_DEV/size` snapshot /dev/$ROOT_DEV /dev/xvdc2 N 16" | \
dmsetup create dmroot || { echo "Qubes: FATAL: cannot create dmroot!"; exit 1; }
echo Qubes: done.
else
echo "Qubes: Doing R/W setup for TemplateVM..."
while ! [ -e /dev/xvdc ]; do sleep 0.1; done
sfdisk -q --unit S /dev/xvdc >/dev/null <<EOF
1,$SWAP_SIZE,S
EOF
if [ $? -ne 0 ]; then
die "Qubes: failed to setup partitions on volatile device"
fi
while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
mkswap /dev/xvdc1
if [ "$ROOT_DEV" = "xvda1" ]; then
# grub2-probe for some reason can't parse dm-linear pointing at
# partition device directly, but can when it points at it indirectly
# through base device and offset; lets make life easier for users of
# grub2-install
DM_ROOT="/dev/xvda $(cat /sys/class/block/$ROOT_DEV/start)"
else
DM_ROOT="/dev/$ROOT_DEV 0"
fi
echo "0 `cat /sys/class/block/$ROOT_DEV/size` linear $DM_ROOT" | \
dmsetup create dmroot || { echo "Qubes: FATAL: cannot create dmroot!"; exit 1; }
echo Qubes: done.
fi
dmsetup mknodes dmroot
modprobe ext4
mkdir -p /sysroot
mount /dev/mapper/dmroot /sysroot -o ro
NEWROOT=/sysroot
kver="`uname -r`"
if ! [ -d "$NEWROOT/lib/modules/$kver/kernel" ]; then
echo "Waiting for /dev/xvdd device..."
while ! [ -e /dev/xvdd ]; do sleep 0.1; done
# Mount only `uname -r` subdirectory, to leave the rest of /lib/modules writable
mkdir -p /tmp/modules
mount -n -t ext3 /dev/xvdd /tmp/modules
if ! [ -d "$NEWROOT/lib/modules/$kver" ]; then
mount "$NEWROOT" -o remount,rw
mkdir -p "$NEWROOT/lib/modules/$kver"
mount "$NEWROOT" -o remount,ro
fi
mount --bind "/tmp/modules/$kver" "$NEWROOT/lib/modules/$kver"
umount /tmp/modules
rmdir /tmp/modules
fi
umount /dev /sys /proc
exec switch_root $NEWROOT /sbin/init