Support multiple Cinder backend types
This is the first step in supporting multiple Cinder backend types at
once. It initially converts the existing hard-coded multi-lvm support
to a new cinder_backends driver form. Eventually the cinder_plugins
will be converted to this form so they can be enabled more than just
one at a time using CINDER_ENABLED_BACKENDS.
The default configuration should be identical to the previous defaults,
including for both True and False values of CINDER_MULTI_LVM_BACKEND.
The existing cinder_plugins are expected to be removed when this is
complete. They should continue to work until they have been converted.
Add wait for c-api to ensure it is started before continuing.
Change-Id: I93b8ef32832269d730c76a6dc24ddb4f20c6d9df
diff --git a/lib/cinder_backends/lvm b/lib/cinder_backends/lvm
new file mode 100644
index 0000000..324c323
--- /dev/null
+++ b/lib/cinder_backends/lvm
@@ -0,0 +1,179 @@
+# lib/cinder_backends/lvm
+# Configure the LVM backend
+
+# Enable with:
+#
+# CINDER_ENABLED_BACKENDS+=,lvm:lvmname
+
+# Dependencies:
+#
+# - ``functions`` file
+# - ``cinder`` configurations
+
+# CINDER_CONF
+# DATA_DIR
+
+# clean_cinder_backend_lvm - called from clean_cinder()
+# configure_cinder_backend_lvm - called from configure_cinder()
+# init_cinder_backend_lvm - called from init_cinder()
+
+
+# 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:-${VOLUME_GROUP_NAME:-stack-volumes}}
+
+# TODO: resurrect backing device...need to know how to set values
+#VOLUME_BACKING_DEVICE=${VOLUME_BACKING_DEVICE:-}
+
+VOLUME_NAME_PREFIX=${VOLUME_NAME_PREFIX:-volume-}
+
+
+# Entry Points
+# ------------
+
+# Compatibility for getting a volume group name from either ``VOLUME_GROUP``
+# or from ``VOLUME_GROUP_NAME`` plus the backend name
+function get_volume_group_name {
+ local be_name=$1
+
+ # Again with the icehouse-generation compatibility
+ local volume_group_name=$VOLUME_GROUP_NAME
+ if [[ -z $VOLUME_GROUP ]]; then
+ volume_group_name+="-$be_name"
+ fi
+ echo $volume_group_name
+}
+
+function cleanup_cinder_backend_lvm {
+ local be_name=$1
+
+ # Again with the icehouse-generation compatibility
+ local volume_group_name=$(get_volume_group_name $be_name)
+
+ # Campsite rule: leave behind a volume group at least as clean as we found it
+ _clean_lvm_lv ${volume_group_name} $VOLUME_NAME_PREFIX
+ _clean_lvm_backing_file ${volume_group_name} $DATA_DIR/${volume_group_name}-backing-file
+}
+
+# configure_cinder_backend_lvm - Set config files, create data dirs, etc
+# configure_cinder_backend_lvm $name
+function configure_cinder_backend_lvm {
+ local be_name=$1
+
+ # Again with the icehouse-generation compatibility
+ local volume_group_name=$(get_volume_group_name $be_name)
+
+ iniset $CINDER_CONF $be_name volume_backend_name $be_name
+ iniset $CINDER_CONF $be_name volume_driver "cinder.volume.drivers.lvm.LVMISCSIDriver"
+ iniset $CINDER_CONF $be_name volume_group $volume_group_name
+
+ if [[ "$CINDER_SECURE_DELETE" == "False" ]]; then
+ iniset $CINDER_CONF $be_name volume_clear none
+ fi
+}
+
+
+function init_cinder_backend_lvm {
+ local be_name=$1
+
+ # Again with the icehouse-generation compatibility
+ local volume_group_name=$(get_volume_group_name $be_name)
+
+ # Start with a clean volume group
+ _create_cinder_volume_group ${volume_group_name} $DATA_DIR/${volume_group_name}-backing-file
+
+ 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 $VOLUME_NAME_PREFIX | grep Target | cut -f3 -d ' ' | sudo xargs -n1 tgt-admin --delete || true
+ _clean_lvm_lv ${volume_group_name} $VOLUME_NAME_PREFIX
+}
+
+
+# _clean_lvm_lv removes all cinder LVM volumes
+#
+# Usage: _clean_lvm_lv volume-group-name $VOLUME_NAME_PREFIX
+function _clean_lvm_lv {
+ local vg=$1
+ local lv_prefix=$2
+
+ # Clean out existing volumes
+ for lv in $(sudo lvs --noheadings -o lv_name $vg 2>/dev/null); do
+ # lv_prefix prefixes the LVs we want
+ if [[ "${lv#$lv_prefix}" != "$lv" ]]; then
+ sudo lvremove -f $vg/$lv
+ fi
+ done
+}
+
+# _clean_lvm_backing_file() removes the backing file of the
+# volume group used by cinder
+#
+# Usage: _clean_lvm_backing_file() volume-group-name backing-file-name
+function _clean_lvm_backing_file {
+ local vg=$1
+ local backing_file=$2
+
+ # if there is no logical volume left, it's safe to attempt a cleanup
+ # of the backing file
+ if [[ -z "$(sudo lvs --noheadings -o lv_name $vg 2>/dev/null)" ]]; then
+ # if the backing physical device is a loop device, it was probably setup by devstack
+ VG_DEV=$(sudo losetup -j $backing_file | awk -F':' '/backing-file/ { print $1}')
+ if [[ -n "$VG_DEV" ]] && [[ -e "$VG_DEV" ]]; then
+ sudo losetup -d $VG_DEV
+ rm -f $backing_file
+ fi
+ fi
+}
+
+# _create_cinder_volume_group volume-group-name backing-file-name
+function _create_cinder_volume_group {
+ # According to the ``CINDER_MULTI_LVM_BACKEND`` value, configure one or two default volumes
+ # group called ``stack-volumes`` (and ``stack-volumes2``) for the volume
+ # service if it (they) does (do) not yet exist. If you don't wish to use a
+ # file backed volume group, create your own volume group called ``stack-volumes``
+ # and ``stack-volumes2`` before invoking ``stack.sh``.
+ #
+ # The two backing files are ``VOLUME_BACKING_FILE_SIZE`` in size, and they are stored in
+ # the ``DATA_DIR``.
+
+ local vg_name=$1
+ local backing_file=$2
+
+ if ! sudo vgs $vg_name; then
+ # TODO: fix device handling
+ if [ -z "$VOLUME_BACKING_DEVICE" ]; then
+ # Only create if the file doesn't already exists
+ [[ -f $backing_file ]] || truncate -s $VOLUME_BACKING_FILE_SIZE $backing_file
+ DEV=`sudo losetup -f --show $backing_file`
+
+ # Only create if the loopback device doesn't contain $VOLUME_GROUP
+ if ! sudo vgs $vg_name; then
+ sudo vgcreate $vg_name $DEV
+ fi
+ else
+ sudo vgcreate $vg_name $VOLUME_BACKING_DEVICE
+ fi
+ fi
+}
+
+
+# Restore xtrace
+$MY_XTRACE
+
+# mode: shell-script
+# End: