#!/bin/bash
 #

 # 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
 
 

 # Functions
 # ---------

 
 # _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_lvm_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 the lvmetad and tgtd services

     if is_fedora || is_suse; then

         # services is not started by default
         start_service lvm2-lvmetad

         if [ "$CINDER_ISCSI_HELPER" = "tgtadm" ]; then
             start_service tgtd
         fi

     fi
 

     # Start with a clean volume group
     _create_lvm_volume_group $vg $size
 

     # Remove iscsi targets

     if [ "$CINDER_ISCSI_HELPER" = "lioadm" ]; then
         sudo cinder-rtstool get-targets | sudo xargs -rn 1 cinder-rtstool delete
     else
         sudo tgtadm --op show --mode target | grep Target | cut -f3 -d ' ' | sudo xargs -n1 tgt-admin --delete || true
     fi

     _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
 }
 

 # clean_lvm_filter() Remove the filter rule set in set_lvm_filter()
 #
 # Usage: clean_lvm_filter()
 function clean_lvm_filter {
     sudo sed -i "s/^.*# from devstack$//" /etc/lvm/lvm.conf
 }
 

 # set_lvm_filter() Gather all devices configured for LVM and
 # use them to build a global device filter
 # set_lvm_filter() Create a device filter
 # and add to /etc/lvm.conf.  Note this uses
 # all current PV's in use by LVM on the
 # system to build it's filter.
 #
 # Usage: set_lvm_filter()
 function set_lvm_filter {

     local filter_suffix='"r|.*|" ]  # from devstack'

     local filter_string="global_filter = [ "
     local pv
     local vg
     local line
 
     for pv_info in $(sudo pvs --noheadings -o name); do
         pv=$(echo -e "${pv_info}" | sed 's/ //g' | sed 's/\/dev\///g')
         new="\"a|$pv|\", "
         filter_string=$filter_string$new
     done
     filter_string=$filter_string$filter_suffix
 

     clean_lvm_filter

     sudo sed -i "/# global_filter = \[*\]/a\    $global_filter$filter_string" /etc/lvm/lvm.conf
     echo_summary "set lvm.conf device global_filter to: $filter_string"
 }

 # Restore xtrace
 $MY_XTRACE
 
 # mode: shell-script
 # End: