setup.sh: detect a free loop device rather than using /dev/loop0

In particular this makes it work in XenServer dom0.

Signed-off-by: David Scott <[email protected]>

Author: David Scott

cleanup.sh

@@ -4,11 +4,11 @@ if [ "$EUID" -ne "0" ]; then
   echo "Please run me as uid 0. I need to create a loop device and device mapper devices"
   exit 1
 fi
-
+LOOP=$(losetup -j bigdisk | cut -f 1 -d ':')
 ./xenvm.native lvchange -an /dev/djstest/live || true
 #./xenvm.native shutdown /dev/djstest
 killall xenvmd.native
 dmsetup remove_all
-dd if=/dev/zero of=/dev/loop0 bs=1M count=128
-losetup -d /dev/loop0
+dd if=/dev/zero of=$LOOP bs=1M count=128
+losetup -d $LOOP
 rm -f localJournal bigdisk *.out

setup.sh

@@ -15,16 +15,18 @@ fi
 # Making a 1G disk
 rm -f bigdisk _build/xenvm*.out
 dd if=/dev/zero of=bigdisk bs=1 seek=256G count=0
-echo Using /dev/loop0
-losetup /dev/loop0 bigdisk
-cat test.xenvmd.conf.in | sed -r "s|@BIGDISK@|/dev/loop0|g" > test.xenvmd.conf
+
+LOOP=$(losetup -f)
+echo Using $LOOP
+losetup $LOOP bigdisk
+cat test.xenvmd.conf.in | sed -r "s|@BIGDISK@|$LOOP|g" > test.xenvmd.conf
 mkdir -p /etc/xenvm.d
-BISECT_FILE=_build/xenvm.coverage ./xenvm.native format /dev/loop0 --vg djstest
+BISECT_FILE=_build/xenvm.coverage ./xenvm.native format $LOOP --vg djstest
 BISECT_FILE=_build/xenvmd.coverage ./xenvmd.native --config ./test.xenvmd.conf --daemon
 
 export BISECT_FILE=_build/xenvm.coverage
 
-./xenvm.native set-vg-info --pvpath /dev/loop0 -S /tmp/xenvmd djstest --local-allocator-path /tmp/xenvm-local-allocator --uri file://local/services/xenvmd/djstest
+./xenvm.native set-vg-info --pvpath $LOOP -S /tmp/xenvmd djstest --local-allocator-path /tmp/xenvm-local-allocator --uri file://local/services/xenvmd/djstest
 
 ./xenvm.native lvcreate -n live -L 4 djstest
 ./xenvm.native lvchange -ay /dev/djstest/live