create-initrd

#!/bin/bash
#
# Copyright (c) 2015 SUSE Linux GmbH
#
# This file is part of the kernel-ci project and licensed under the GNU GPLv2
#

DEFPROGRAMS=(sh cp rm mkdir cat chroot echo insmod modprobe mount sleep)
#MODULES=('efivarfs.ko' 'mcb.ko' 'mcb-pci.ko')

DEFROOT="/dev/vda3"
O=$(pwd)

#
# $1 program
copy_libs_for_prog()
{
	local prog libs
	prog=$1

	libs=$(ldd ${prog} | cut -d '>' -f 2 | cut -d ' ' -f 2 | grep ^/)
	for l in ${libs}; do
		cp $l lib64
	done
}

usage()
{
	echo "Usage: $1 [-f '<file[ <file>][...]'] [-i init] [-k kdir ] [-m '<module[ <module>][...]'] [-o <outdir>] [-r root]" >&2
	echo "" >&2
	echo "  -f Space separated list of files to include in initrd" >&2
	echo "     image." >&2
	echo "  -i bin/init source." >&2
	echo "  -k Directory having the kernel sources." >&2
	echo "  -m Space separated list of kernel modules to include" >&2
	echo "     in initrd image." >&2
	echo "  -p Space separated list of programs to include in" >&2
	echo "     initrd image." >&2
	echo "  -o <outdir> generate everything into <outdir>" >&2
	echo "  -r root= kernel option (default $DEFROOT)."  >&2
	exit 1
}

program=$(basename $0)
while getopts "f:i:hk:m:p:o:r:?" flag; do
	case ${flag} in
		f)
			FILES=${OPTARG}
			;;
		i)
			INIT_SRC=${OPTARG}
			;;
		k)
			KDIR=${OPTARG}
			;;
		m)
			MODULES=(${OPTARG})
			;;
		p)
			PROGRAMS=(${OPTARG})
			;;
		o)
			O=${OPTARG}
			;;
		r)
			ROOT=${OPTARG}
			;;
		[?h])
			usage ${program}
			exit 1
			;;
		*)
			echo "invalid option"
			usage ${program}
			exit 1
			;;
	esac
done

if [ x"$ROOT" == "x" ]; then
	ROOT=$DEFROOT
fi

if [ x"$PROGRAMS" == "x" ]; then
	PROGRAMS=("${DEFPROGRAMS[@]}")
fi

# set to CWD in case we're called in the kernel build dir
if [ x"$KDIR" == "x" ]; then
	KDIR=$(pwd)
fi

krel=$(make -s -C "$KDIR" kernelrelease)
O=$(cd "$O"; pwd)
TMPDIR=$(mktemp -qd)
mkdir -p $TMPDIR/initrd/{bin,dev,etc,lib/modules,lib64,proc,sys,sysroot,root}
pushd $TMPDIR/initrd >/dev/null
ln -s bin sbin

if [ x"$INIT_SRC" == "x" ]; then
	echo "#!/bin/sh" >> bin/init

	for mod in "${MODULES[@]}"; do
		echo "echo \"Loading ${mod}\"" >> bin/init
		echo "modprobe ${mod%.ko}" >> bin/init
	done

	cat >> bin/init << __EOF__

echo "Mounting /proc, /dev and /sys"
mount -t proc /proc /proc
mount -t sysfs /sys /sys
mount -t devtmpfs /dev /dev

# Mount rootfs to /sysroot
mount $ROOT /sysroot

echo "Copying kernel modules to new root"
mkdir /sysroot/lib/modules/$krel
cp /lib/modules/$krel/* /sysroot/lib/modules/$krel/
# Disable the JeOS wizard
rm -f /sysroot/usr/lib/systemd/system/sysinit.target.wants/jeos-firstboot.service
echo "Switching to new root"
cd /sysroot
exec chroot . sh -c 'exec /sbin/init'

__EOF__
else
	cp ${INIT_SRC} bin/init
fi

chmod 755 bin/init

if [ -x /usr/bin/busybox-static ]; then
	cp /usr/bin/busybox-static bin/busybox
	for prog in "${PROGRAMS[@]}"; do
		ln -s busybox "bin/$prog"
	done
else
	LD_2=`rpm -ql glibc | grep ld-2`
	LD_LINUX=`rpm -ql glibc | grep ld-linux`
	for lib in ${LD_2} ${LD_LINUX}; do
		cp ${lib} lib64/
	done

	for prog in ${PROGRAMS[@]}; do
		absprog=$(which ${prog})
		if [ -z ${absprog} ]; then
			if [ ! -f /sbin/${prog} ]; then
				echo "${prog} not found, skipping.."
			else
				absprog=/sbin/${prog}
			fi
			continue
		fi
		cp ${absprog} bin/
		copy_libs_for_prog ${absprog}
	done
fi

if [ x"$KDIR" != "x" ]; then
	KDIR=$(realpath $KDIR)
	mkdir -p "lib/modules/$krel"
	cp "$KDIR/modules.order" "$KDIR/modules.builtin" "lib/modules/$krel" 2>/dev/null
	set -- "${MODULES[@]}"
	while test $# -gt 0; do
		# This is not a noop: it replaces [-_] with a literal [-_] to
		# use with find(1), because module names use - and _
		# interchangeably
		mod=${1//[-_]/[-_]}
		shift
		if find "lib/modules/$krel" -name "$mod" | grep -q .; then
			continue
		fi
		file=$(find $KDIR -name "$mod.ko")
		if test -z "$file"; then
			echo "warning: module $mod not found"
			continue
		fi
		for f in "${file[@]}"; do
			cp "$f" "lib/modules/$krel"
		done
		for dep in $(/sbin/modinfo -F depends "$file" | sed 's/,/ /g'); do
			set -- "$@" "$dep"
		done
	done
	/sbin/depmod -F "$KDIR/System.map" -e -b "$PWD" "$krel"
fi

if [ "x$FILES" != "x" ]; then
	for file in ${FILES}; do
		cp ${file} root/
	done
fi

find ./ | cpio --quiet -H newc -o > $O/initrd.cpio
popd >/dev/null

gzip -9 -c $O/initrd.cpio > $O/initrd.img
rm -rf $O/initrd.cpio

if [[ ! -d /lib/firmware/amd-ucode && ! -d /lib/firmware/intel-ucode ]]; then
	rm -rf $TMPDIR
	exit 0
fi

# microcode
UCODE_DIR=$TMPDIR/kernel/x86/microcode

mkdir -p $UCODE_DIR

if [ -d /lib/firmware/amd-ucode ]; then
	cat /lib/firmware/amd-ucode/microcode_amd*.bin > $UCODE_DIR/AuthenticAMD.bin
fi

if [ -d /lib/firmware/intel-ucode ]; then
	cat /lib/firmware/intel-ucode/* > $UCODE_DIR/GenuineIntel.bin
fi

cd $TMPDIR
find . | cpio --quiet -H newc -o > $O/microcode.cpio
cat $O/microcode.cpio $O/initrd.img > $O/initrd.microcode.img
mv -f $O/initrd.microcode.img $O/initrd.img

rm -rf $O/microcode.cpio
rm -rf $TMPDIR