1 files changed, 69 insertions, 5 deletions

diff --git a/target/linux/mvebu/base-files/lib/upgrade/sdcard.sh b/target/linux/mvebu/base-files/lib/upgrade/sdcard.sh
index 7aa91f463c..28fad31757 100644
--- a/target/linux/mvebu/base-files/lib/upgrade/sdcard.sh
+++ b/target/linux/mvebu/base-files/lib/upgrade/sdcard.sh
@@ -6,7 +6,7 @@ get_magic_at() {
 
 platform_check_image_sdcard() {
 	local file="$1"
-	local magic
+	local magic diskdev partdev diff
 
 	magic=$(get_magic_at "$file" 510)
 	[ "$magic" != "55aa" ] && {
@@ -14,18 +14,82 @@ platform_check_image_sdcard() {
 		return 1
 	}
 
-	return 0;
+	export_bootdevice && export_partdevice diskdev 0 || {
+		echo "Unable to determine upgrade device"
+	return 1
+	}
+
+	get_partitions "/dev/$diskdev" bootdisk
+
+	#extract the boot sector from the image
+	get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b 2>/dev/null
+
+	get_partitions /tmp/image.bs image
+
+	#compare tables
+	diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)"
+
+	rm -f /tmp/image.bs /tmp/partmap.bootdisk /tmp/partmap.image
+
+	if [ -n "$diff" ]; then
+		echo "Partition layout has changed. Full image will be written."
+		ask_bool 0 "Abort" && exit 1
+		return 0
+	fi
 }
 
 platform_do_upgrade_sdcard() {
 	local board=$(board_name)
-	local diskdev
+	local diskdev partdev diff
+
+	export_bootdevice && export_partdevice diskdev 0 || {
+		echo "Unable to determine upgrade device"
+	return 1
+	}
 
 	sync
-	if export_bootdevice && export_partdevice diskdev 0; then
-		get_image "$1" | dd of=/dev/$diskdev bs=2M conv=fsync
+
+	if [ "$SAVE_PARTITIONS" = "1" ]; then
+		get_partitions "/dev/$diskdev" bootdisk
+
+		#extract the boot sector from the image
+		get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b
+
+		get_partitions /tmp/image.bs image
+
+		#compare tables
+		diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)"
+	else
+		diff=1
+	fi
+
+	if [ -n "$diff" ]; then
+		get_image "$@" | dd of="/dev/$diskdev" bs=4096 conv=fsync
+
+		# Separate removal and addtion is necessary; otherwise, partition 1
+		# will be missing if it overlaps with the old partition 2
+		partx -d - "/dev/$diskdev"
+		partx -a - "/dev/$diskdev"
+
+		return 0
 	fi
 
+	#write uboot image
+	get_image "$@" | dd of="$diskdev" bs=512 skip=1 seek=1 count=2048 conv=fsync
+	#iterate over each partition from the image and write it to the boot disk
+	while read part start size; do
+		if export_partdevice partdev $part; then
+			echo "Writing image to /dev/$partdev..."
+			get_image "$@" | dd of="/dev/$partdev" ibs="512" obs=1M skip="$start" count="$size" conv=fsync
+		else
+			echo "Unable to find partition $part device, skipped."
+		fi
+	done < /tmp/partmap.image
+
+	#copy partition uuid
+	echo "Writing new UUID to /dev/$diskdev..."
+	get_image "$@" | dd of="/dev/$diskdev" bs=1 skip=440 count=4 seek=440 conv=fsync
+
 	case "$board" in
 	armada-385-turris-omnia)
 		fw_setenv openwrt_bootargs 'earlyprintk console=ttyS0,115200 root=/dev/mmcblk0p2 rootfstype=auto rootwait'