# lib/lvm

# Configure the default LVM volume group used by Cinder and Nova

# Dependencies:

#

# - ``functions`` file

# - ``cinder`` configurations

# DATA_DIR

# clean_default_volume_group - called from clean()

# configure_default_volume_group - called from configure()

# init_default_volume_group - called from init()

# Save trace setting

MY_XTRACE=$(set +o | grep xtrace)

set +o xtrace

# Defaults

# --------

# Name of the lvm volume groups to use/create for iscsi volumes

# This monkey-motion is for compatibility with icehouse-generation Grenade

# If ``VOLUME_GROUP`` is set, use it, otherwise we'll build a VG name based

# on ``VOLUME_GROUP_NAME`` that includes the backend name

# Grenade doesn't use ``VOLUME_GROUP2`` so it is left out

VOLUME_GROUP_NAME=${VOLUME_GROUP:-${VOLUME_GROUP_NAME:-stack-volumes}}

DEFAULT_VOLUME_GROUP_NAME=$VOLUME_GROUP_NAME-default

# Backing file name is of the form $VOLUME_GROUP$BACKING_FILE_SUFFIX

BACKING_FILE_SUFFIX=-backing-file

# Entry Points

# ------------

# _clean_lvm_volume_group removes all default LVM volumes

#

# Usage: clean_lvm_volume_group $vg

function _clean_lvm_volume_group {

local vg=$1

# Clean out existing volumes

sudo lvremove -f $vg

}

# _clean_lvm_backing_file() removes the backing file of the

# volume group

#

# Usage: _clean_lvm_backing_file() $backing_file

function _clean_lvm_backing_file {

local backing_file=$1

# if the backing physical device is a loop device, it was probably setup by devstack

if [[ -n "$backing_file" ]] && [[ -e "$backing_file" ]]; then

local vg_dev=$(sudo losetup -j $backing_file | awk -F':' '/'$BACKING_FILE_SUFFIX'/ { print $1}')

sudo losetup -d $vg_dev

rm -f $backing_file

fi

}

# clean_lvm_volume_group() cleans up the volume group and removes the

# backing file

#

# Usage: clean_lvm_volume_group $vg

function clean_lvm_volume_group {

local vg=$1

_clean_lvm_volume_group $vg

# if there is no logical volume left, it's safe to attempt a cleanup

# of the backing file

if [[ -z "$(sudo lvs --noheadings -o lv_name $vg 2>/dev/null)" ]]; then

_clean_lvm_backing_file $DATA_DIR/$vg$BACKING_FILE_SUFFIX

fi

}

# _create_volume_group creates default volume group

#

# Usage: _create_lvm_volume_group() $vg $size

function _create_lvm_volume_group {

local vg=$1

local size=$2

local backing_file=$DATA_DIR/$vg$BACKING_FILE_SUFFIX

if ! sudo vgs $vg; then

# Only create if the file doesn't already exists

[[ -f $backing_file ]] || truncate -s $size $backing_file

local vg_dev=`sudo losetup -f --show $backing_file`

# Only create volume group if it doesn't already exist

if ! sudo vgs $vg; then

sudo vgcreate $vg $vg_dev

fi

fi

}

# init_lvm_volume_group() initializes the volume group creating the backing

# file if necessary

#

# Usage: init_lvm_volume_group() $vg

function init_lvm_volume_group {

local vg=$1

local size=$2

# Start with a clean volume group

_create_lvm_volume_group $vg $size

if is_fedora || is_suse; then

# service is not started by default

start_service tgtd

fi

# Remove iscsi targets

sudo tgtadm --op show --mode target | grep Target | cut -f3 -d ' ' | sudo xargs -n1 tgt-admin --delete || true

_clean_lvm_volume_group $vg

}

# Sentinal value to ensure that init of default lvm volume group is

# only performed once across calls of init_default_lvm_volume_group.

_DEFAULT_LVM_INIT=${_DEFAULT_LVM_INIT:-0}

# init_default_lvm_volume_group() initializes a default volume group

# intended to be shared between cinder and nova. It is idempotent;

# the init of the default volume group is guaranteed to be performed

# only once so that either or both of the dependent services can

# safely call this function.

#

# Usage: init_default_lvm_volume_group()

function init_default_lvm_volume_group {

if [[ "$_DEFAULT_LVM_INIT" = "0" ]]; then

init_lvm_volume_group $DEFAULT_VOLUME_GROUP_NAME $VOLUME_BACKING_FILE_SIZE

_DEFAULT_LVM_INIT=1

fi

}

# Restore xtrace

$MY_XTRACE

# mode: shell-script

# End: