From 5e770591377a595bbea995effbd3e41e125d4e29 Mon Sep 17 00:00:00 2001
From: devrandom <c1.github@niftybox.net>
Date: Sun, 22 Apr 2012 10:42:18 -0700
Subject: [PATCH] Using backing image instead of copy for qemu image.  From
 lukejr.

---
 libexec/make-clean-vm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libexec/make-clean-vm b/libexec/make-clean-vm
index 5c66a27..2e4a633 100755
--- a/libexec/make-clean-vm
+++ b/libexec/make-clean-vm
@@ -45,7 +45,7 @@ BASE=base-$SUITE-$ARCH-root
 OUT=target-$SUITE-$ARCH-root
 
 if [ -z "$USE_LXC" ]; then
-    cp $BASE.qcow2 $OUT.qcow2
+    qemu-img create -f qcow2 -o backing_file="$BASE.qcow2" "$OUT.qcow2"
 else
     sudo rm -rf $OUT
     sudo cp -a $BASE $OUT