From 22853c1974ca1ce50b946290bc7bf9b2dd34b64d Mon Sep 17 00:00:00 2001
From: Dean Troyer <dtroyer@gmail.com>
Date: Mon, 7 Jan 2013 15:18:12 -0600
Subject: [PATCH] Clean up cinder volume group rather than remove it

Removing the cinder volume group breaks devstack installations
that share that volume group with other logical volumes. It also was
leaking loopback devices.

Change-Id: Ice4470e06e08ce49a0e1f82af70abcc015c91c20
---
 lib/cinder | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/lib/cinder b/lib/cinder
index 385a5a2a33..8949cfcccd 100644
--- a/lib/cinder
+++ b/lib/cinder
@@ -48,6 +48,20 @@ fi
 VOLUME_GROUP=${VOLUME_GROUP:-stack-volumes}
 VOLUME_NAME_PREFIX=${VOLUME_NAME_PREFIX:-volume-}
 
+# _clean_volume_group removes all cinder volumes from the specified volume group
+# _clean_volume_group $VOLUME_GROUP $VOLUME_NAME_PREFIX
+function _clean_volume_group() {
+    local vg=$1
+    local vg_prefix=$2
+    # Clean out existing volumes
+    for lv in `sudo lvs --noheadings -o lv_name $vg`; do
+        # vg_prefix prefixes the LVs we want
+        if [[ "${lv#$vg_prefix}" != "$lv" ]]; then
+            sudo lvremove -f $vg/$lv
+        fi
+    done
+}
+
 # cleanup_cinder() - Remove residual data files, anything left over from previous
 # runs that a clean run would need to clean up
 function cleanup_cinder() {
@@ -84,7 +98,8 @@ function cleanup_cinder() {
         stop_service tgtd
     fi
 
-    sudo vgremove -f $VOLUME_GROUP
+    # Campsite rule: leave behind a volume group at least as clean as we found it
+    _clean_volume_group $VOLUME_GROUP $VOLUME_NAME_PREFIX
 }
 
 # configure_cinder() - Set config files, create data dirs, etc
@@ -272,13 +287,8 @@ function init_cinder() {
 
             # 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 out existing volumes
-            for lv in `sudo lvs --noheadings -o lv_name $VOLUME_GROUP`; do
-                # VOLUME_NAME_PREFIX prefixes the LVs we want
-                if [[ "${lv#$VOLUME_NAME_PREFIX}" != "$lv" ]]; then
-                    sudo lvremove -f $VOLUME_GROUP/$lv
-                fi
-            done
+            # Start with a clean volume group
+            _clean_volume_group $VOLUME_GROUP $VOLUME_NAME_PREFIX
         fi
     fi