btrfs-progs: tests: convert misc/006-image-on-missing-device to loopdevs

Signed-off-by: David Sterba <dsterba@suse.com>

tests/misc-tests/006-image-on-missing-device/test.sh

@@ -10,38 +10,8 @@ check_prereq btrfs-image
 check_prereq mkfs.btrfs
 check_prereq btrfs
 
-ndevs=2
-declare -a devs
-dev1=
-dev2=
-
 setup_root_helper
 
-
-# TODO: move the helpers to common
-
-prepare_devices()
-{
-	for i in `seq $ndevs`; do
-		touch img$i
-		chmod a+rw img$i
-		truncate -s0 img$i
-		truncate -s2g img$i
-		devs[$i]=`run_check_stdout $SUDO_HELPER losetup --find --show img$i`
-	done
-}
-
-cleanup_devices()
-{
-	for dev in ${devs[@]}; do
-		run_mayfail $SUDO_HELPER losetup -d $dev
-	done
-	for i in `seq $ndevs`; do
-		truncate -s0 img$i
-	done
-	run_check $SUDO_HELPER losetup --all
-}
-
 test_image_dump()
 {
 	run_check $SUDO_HELPER $TOP/btrfs check $dev1
@@ -65,13 +35,15 @@ test_run()
 	# btrfs-image must not loop
 	run_mayfail wipefs -a $dev2
 	run_check $SUDO_HELPER losetup -d $dev2
+	unset loopdevs[2]
 	run_check $SUDO_HELPER $TOP/btrfs filesystem show $dev1
 
 	test_image_dump
 }
 
-prepare_devices
-dev1=${devs[1]}
-dev2=${devs[2]}
+setup_loopdevs 2
+prepare_loopdevs
+dev1=${loopdevs[1]}
+dev2=${loopdevs[2]}
 test_run
-cleanup_devices
+cleanup_loopdevs