use a single partitioned loop device (#641)

export-image/prerun.sh

@@ -33,41 +33,21 @@ if [ "${NO_PRERUN_QCOW2}" = "0" ]; then
 	parted --script "${IMG_FILE}" unit B mkpart primary fat32 "${BOOT_PART_START}" "$((BOOT_PART_START + BOOT_PART_SIZE - 1))"
 	parted --script "${IMG_FILE}" unit B mkpart primary ext4 "${ROOT_PART_START}" "$((ROOT_PART_START + ROOT_PART_SIZE - 1))"
 
-	PARTED_OUT=$(parted -sm "${IMG_FILE}" unit b print)
-	BOOT_OFFSET=$(echo "$PARTED_OUT" | grep -e '^1:' | cut -d':' -f 2 | tr -d B)
-	BOOT_LENGTH=$(echo "$PARTED_OUT" | grep -e '^1:' | cut -d':' -f 4 | tr -d B)
-
-	ROOT_OFFSET=$(echo "$PARTED_OUT" | grep -e '^2:' | cut -d':' -f 2 | tr -d B)
-	ROOT_LENGTH=$(echo "$PARTED_OUT" | grep -e '^2:' | cut -d':' -f 4 | tr -d B)
-
-	echo "Mounting BOOT_DEV..."
-	cnt=0
-	until BOOT_DEV=$(losetup --show -f -o "${BOOT_OFFSET}" --sizelimit "${BOOT_LENGTH}" "${IMG_FILE}"); do
-		if [ $cnt -lt 5 ]; then
-			cnt=$((cnt + 1))
-			echo "Error in losetup for BOOT_DEV.  Retrying..."
-			sleep 5
-		else
-			echo "ERROR: losetup for BOOT_DEV failed; exiting"
-			exit 1
-		fi
-	done
-
-	echo "Mounting ROOT_DEV..."
+	echo "Creating loop device..."
 	cnt=0
-	until ROOT_DEV=$(losetup --show -f -o "${ROOT_OFFSET}" --sizelimit "${ROOT_LENGTH}" "${IMG_FILE}"); do
+	until LOOP_DEV="$(losetup --show --find --partscan "$IMG_FILE")"; do
 		if [ $cnt -lt 5 ]; then
 			cnt=$((cnt + 1))
-			echo "Error in losetup for ROOT_DEV.  Retrying..."
+			echo "Error in losetup.  Retrying..."
 			sleep 5
 		else
-			echo "ERROR: losetup for ROOT_DEV failed; exiting"
+			echo "ERROR: losetup failed; exiting"
 			exit 1
 		fi
 	done
 
-	echo "/boot: offset $BOOT_OFFSET, length $BOOT_LENGTH"
-	echo "/:     offset $ROOT_OFFSET, length $ROOT_LENGTH"
+	BOOT_DEV="${LOOP_DEV}p1"
+	ROOT_DEV="${LOOP_DEV}p2"
 
 	ROOT_FEATURES="^huge_file"
 	for FEATURE in 64bit; do

export-noobs/prerun.sh

@@ -9,41 +9,21 @@ unmount_image "${IMG_FILE}"
 
 rm -rf "${NOOBS_DIR}"
 
-PARTED_OUT=$(parted -sm "${IMG_FILE}" unit b print)
-BOOT_OFFSET=$(echo "$PARTED_OUT" | grep -e '^1:' | cut -d':' -f 2 | tr -d B)
-BOOT_LENGTH=$(echo "$PARTED_OUT" | grep -e '^1:' | cut -d':' -f 4 | tr -d B)
-
-ROOT_OFFSET=$(echo "$PARTED_OUT" | grep -e '^2:' | cut -d':' -f 2 | tr -d B)
-ROOT_LENGTH=$(echo "$PARTED_OUT" | grep -e '^2:' | cut -d':' -f 4 | tr -d B)
-
-echo "Mounting BOOT_DEV..."
-cnt=0
-until BOOT_DEV=$(losetup --show -f -o "${BOOT_OFFSET}" --sizelimit "${BOOT_LENGTH}" "${IMG_FILE}"); do
-	if [ $cnt -lt 5 ]; then
-		cnt=$((cnt + 1))
-		echo "Error in losetup for BOOT_DEV.  Retrying..."
-		sleep 5
-	else
-		echo "ERROR: losetup for BOOT_DEV failed; exiting"
-		exit 1
-	fi
-done
-
-echo "Mounting ROOT_DEV..."
+echo "Creating loop device..."
 cnt=0
-until ROOT_DEV=$(losetup --show -f -o "${ROOT_OFFSET}" --sizelimit "${ROOT_LENGTH}" "${IMG_FILE}"); do
+until LOOP_DEV="$(losetup --show --find --partscan "$IMG_FILE")"; do
 	if [ $cnt -lt 5 ]; then
 		cnt=$((cnt + 1))
-		echo "Error in losetup for ROOT_DEV.  Retrying..."
+		echo "Error in losetup.  Retrying..."
 		sleep 5
 	else
-		echo "ERROR: losetup for ROOT_DEV failed; exiting"
+		echo "ERROR: losetup failed; exiting"
 		exit 1
 	fi
 done
 
-echo "/boot: offset $BOOT_OFFSET, length $BOOT_LENGTH"
-echo "/:     offset $ROOT_OFFSET, length $ROOT_LENGTH"
+BOOT_DEV="${LOOP_DEV}p1"
+ROOT_DEV="${LOOP_DEV}p2"
 
 mkdir -p "${STAGE_WORK_DIR}/rootfs"
 mkdir -p "${NOOBS_DIR}"

scripts/common

@@ -57,19 +57,15 @@ export -f unmount
 unmount_image(){
 	sync
 	sleep 1
-	local LOOP_DEVICES
-	LOOP_DEVICES=$(losetup --list | grep "$(basename "${1}")" | cut -f1 -d' ')
-	for LOOP_DEV in ${LOOP_DEVICES}; do
-		if [ -n "${LOOP_DEV}" ]; then
-			local MOUNTED_DIR
-			MOUNTED_DIR=$(mount | grep "$(basename "${LOOP_DEV}")" | head -n 1 | cut -f 3 -d ' ')
-			if [ -n "${MOUNTED_DIR}" ] && [ "${MOUNTED_DIR}" != "/" ]; then
-				unmount "$(dirname "${MOUNTED_DIR}")"
+	LOOP_DEVICE=$(losetup --list | grep "$1" | cut -f1 -d' ')
+	if [ -n "$LOOP_DEVICE" ]; then
+		for part in "$LOOP_DEVICE"p*; do
+			if DIR=$(findmnt -n -o target -S "$part"); then
+				unmount "$DIR"
 			fi
-			sleep 1
-			losetup -d "${LOOP_DEV}"
-		fi
-	done
+		done
+		losetup -d "$LOOP_DEVICE"
+	fi
 }
 export -f unmount_image