- modularize lvm

[projects/geninitrd.git] / mod-lvm.sh

#!/bin/sh
#
# geninitrd mod: LVM

# if we should init LVM at boot
have_lvm=no

# LVM volumes that are needed to activate
# VG for root dev
# @internal
ROOTVG=""

# VG for suspend resume dev
SUSPENDVG=""

VGVOLUMES=""

if [ -x /sbin/lvm ]; then
	USE_LVM=yes
else
	USE_LVM=no
fi

# LVM devices that should not be included in vgscan on initrd.
# @internal
lvm_ignore_devices=''

# return true if node is lvm node
# @param	string $node device node to be examined
# @access	public
is_lvm() {
	local node="$1"

	# LVM not wanted
	if is_no "$USE_LVM"; then
		return 1
	fi

	if [ ! -e "$node" ]; then
		die "check_lvm(): node $node doesn't exist!"
		return 1
	fi

	# block-major-58 is lvm1
	ls -lL "$node" 2> /dev/null | awk '{if (/^b/) { if ($5 == "58,") { exit 0; } else { exit 1; } } else { exit 1; }}'
	rc=$?

	if [ $rc = 0 ]; then
		# is lvm1
		return 0
	fi

	/sbin/lvm lvdisplay "$node" > /dev/null 2>&1
	rc=$?
	if [ $rc -gt 127 ]; then
		# lvdisplay terminated by signal! most likely it segfaulted.
		die "Unexpected exit from 'lvdisplay $node': $rc - are your lvm tools broken?"
	fi

	return $rc
}

# find modules for $devpath
# @param	$devpath	device to be examined
# @access	public
find_modules_lvm() {
	local devpath="$1"

	debug "LVM: $devpath is LVM node"

	if [ ! -f /sbin/initrd-lvm -o ! -x /sbin/lvdisplay -o ! -x /sbin/pvdisplay ]; then
		die "root on LVM but /sbin/initrd-lvm, /sbin/lvdisplay and /sbin/pvdisplay not found. Please install lvm(2) and lvm(2)-initrd package and rerun $PROGRAM."
	fi

	if [ -z "$LVMTOOLSVERSION" ]; then
		LVMTOOLSVERSION=$(/sbin/initrd-lvm vgchange --version 2>/dev/null|head -n 1|awk '{gsub("vgchange: Logical Volume Manager ",NIL); gsub("LVM version:     ",NIL); gsub(/\..*/,NIL); print $1}')
		if [ -z "$LVMTOOLSVERSION" ]; then
			die "Can't determine LVM tools version. Please set LVMTOOLSVERSION and rerun $PROGRAM."
		fi
	fi

	local vg=$(find_lvm_vg "$devpath")
	debug "LVM VG for $devpath: $vg"
	VGVOLUMES=$(echo $VGVOLUMES $vg | tr ' ' '\n' | sort -u)

	local pv=$(find_lvm_pv "$vg")
	debug "LVM PV for $vg: $pv"
	PVDEVICES=$(echo $PVDEVICES $pv | tr ' ' '\n' | sort -u)

	if [ -n "$PVDEVICES" ]; then
		for device in $PVDEVICES; do
			find_modules_for_devpath $device
		done
	else
		die "I wasn't able to find PV (via lvdisplay and pvdisplay). You can try to set PVDEVICES in /etc/sysconfig/geninitrd."
	fi

	if [ "$LVMTOOLSVERSION" = "2" ]; then
		findmodule "-dm-mod"
	elif [ "$LVMTOOLSVERSION" = "1" ]; then
		findmodule "-lvm"
		findmodule "-lvm-mod"
	else
		die "LVM version $LVMTOOLSVERSION is not supported yet."
	fi

	debug "LVM v$LVMTOOLSVERSION enabled"
	have_lvm=yes
}


# generate initrd fragment for lvm
# @access	public
initrd_gen_lvm() {
	debug "Adding LVM support to initrd"
	inst_d /tmp /newroot
	inst_exec /sbin/initrd-lvm /bin/lvm.static

	# always make /dev on tmpfs for LVM2
	if [ "$LVMTOOLSVERSION" = "2" ]; then
		mount_dev
	fi

	if ! is_yes "$dev_mounted"; then
		inst_d /dev/mapper
		mknod $DESTDIR/dev/mapper/control c 10 63
		for device in $PVDEVICES; do
			# if LVM on RAID then device might be copied already in gen_md
			[ -e "$DESTDIR/dev/$(basename $device)" ] && continue
			inst $device /dev
		done
	fi

	mount_tmp
	if [ "$LVMTOOLSVERSION" = "1" ]; then
		add_linuxrc <<-EOF
			lvm vgscan -T
			for vg in $VGVOLUMES; do
				lvm vgchange -T -a y $vg
			done
		EOF
	else
		echo "cat /etc/lvm.conf > /tmp/lvm.conf" | add_linuxrc
		echo "global {" > "$DESTDIR/etc/lvm.conf"
		echo "	locking_type = 0" >> "$DESTDIR/etc/lvm.conf"
		echo "	locking_dir = \"/tmp\"" >> "$DESTDIR/etc/lvm.conf"
		echo "}" >> "$DESTDIR/etc/lvm.conf"
		echo "devices {" >> "$DESTDIR/etc/lvm.conf"
		echo "	sysfs_scan=0" >> "$DESTDIR/etc/lvm.conf"
		if is_yes "$have_md"; then
			echo "	md_component_detection = 1" >> "$DESTDIR/etc/lvm.conf"
		fi
		if is_yes "$have_dmraid" || is_yes "$have_multipath"; then
			echo '	types = [ "device-mapper", 254 ]' >> "$DESTDIR/etc/lvm.conf"
		fi
		if [ "$lvm_ignore_devices" ]; then
			# TODO: think of merging with lvm dumpconfig output
			echo '	filter = [' >> "$DESTDIR/etc/lvm.conf"
			local dev
			for dev in $lvm_ignore_devices; do
				debug "LVM v2: ignore device $dev"
				printf '  "r|^%s.*|",\n' $dev
			done >> "$DESTDIR/etc/lvm.conf"
			echo ']' >> "$DESTDIR/etc/lvm.conf"
		fi
		# XXX filter= must be on one line!
		lvm dumpconfig | awk '/filter=/' >> "$DESTDIR/etc/lvm.conf"
		echo "}" >> "$DESTDIR/etc/lvm.conf"

		initrd_gen_devices

		add_linuxrc <<-EOF
			export ROOTDEV=$rootdev
			export ROOTVG="$VGVOLUMES"
			export SUSPENDVG=$SUSPENDVG
		EOF
		add_linuxrc <<-'EOF'
			# parse rootdev from kernel commandline if it begins with /
			case "$ROOT" in
				/*)
				if [ "$ROOT" != "$ROOTDEV" ]; then
					ROOTDEV=$ROOT
					echo "LVM: Using 'root=$ROOTDEV' from kernel commandline"
					local tmp=${ROOTDEV#/dev/}
					if [ "$tmp" != "$ROOTDEV" ]; then
						ROOTVG=${tmp%/*}
						echo "LVM: Using Volume Group '$ROOTVG' for rootfs"
					fi
				fi
				;;
			esac

			# skip duplicate VG
			if [ "$SUSPENDVG" = "$ROOTVG" ]; then
				export VGVOLUMES="$ROOTVG"
			else
				export VGVOLUMES="$SUSPENDVG $ROOTVG"
			fi

			# disable noise from LVM accessing devices that aren't ready.
			read printk < /proc/sys/kernel/printk
			if [ ! "$DEBUGINITRD" ]; then
				echo 0 > /proc/sys/kernel/printk
			fi

			export LVM_SYSTEM_DIR=/tmp
			: 'Scanning for Volume Groups'
			lvm.static vgscan --mknodes --ignorelockingfailure 2>/dev/null

			: 'Activating Volume Groups'
			for vol in $VGVOLUMES; do
				lvm.static vgchange --ignorelockingfailure -a y $vol 2>/dev/null
			done

			echo "$printk" > /proc/sys/kernel/printk

			# Find out major/minor
			attrs="$(lvm.static lvdisplay --ignorelockingfailure -c $ROOTDEV 2>/dev/null)"
			if [ "$attrs" ]; then
				majmin="${attrs#*$ROOTDEV*:*:*:*:*:*:*:*:*:*:*:*}"
				if [ "$majmin" != "$attrs" ]; then
					major="${majmin%:*}"
					minor="${majmin#*:}"
				fi
			fi

			if [ "$major" -a "$minor" ]; then
				# Pass it to kernel
				echo $((256 * $major + $minor)) > /proc/sys/kernel/real-root-dev
			else
				echo 2>&1 "Error figuring out real root device for $ROOTDEV!"
				echo 2>&1 "System will not most likely boot up! So dropping you to a shell!"
				echo 2>&1 ""
				sh
			fi
		EOF
	fi
}


# PRIVATE METHODS

# find PV names from given VG name
# @param	string $vg Volume Group name
# @access	private
find_lvm_pv() {
	local vg="$1"

	local pv=$(/sbin/vgdisplay -C --noheadings -o pv_name "$vg")
	echo $pv
}

# find VG name from given devnode
# @param	string $devnode device node to be examined
# @access	private
find_lvm_vg() {
	local devnode="$1"

	local vg=$(/sbin/lvdisplay -C --noheadings -o vg_name "$devnode")
	echo $vg
}