apm821xx: use x86's upgrade scripts for MyBook Live
authorChristian Lamparter <chunkeey@gmail.com>
Fri, 1 Dec 2017 21:41:11 +0000 (22:41 +0100)
committerJohn Crispin <john@phrozen.org>
Thu, 14 Dec 2017 08:29:30 +0000 (09:29 +0100)
Advantages:
 - preserves existing partition layout. On the hard-drive.
   Only the boot and rootfs partition will be overwritten.

Disadvantages:
 - The upgrade process takes much longer to run.
   from 2-3 seconds to 15-25 seconds.

Please note that sysupgrade will refuse to upgrade, if the existing
installation has an incompatible partition layout. Future changes
to the bootfs and/or rootfs partition size will likely cause breakage
to the sysupgrade procedure. In these cases, the ext4-rootfs.img.gz
has to be written manually onto the disk. Please don't forget to backup
your configuration in this cases.

Note2: This patch requires
"base-files: upgrade: make get_partitions() endian agnostic"

Note3: If your current installation does not host the two
changes, sysupgrading will wipe the existing partition
layout. Don't forget to backup your data!

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
target/linux/apm821xx/base-files/lib/upgrade/platform.sh
target/linux/apm821xx/base-files/lib/upgrade/wdbook.sh

index 55f8ffa..8c716bf 100755 (executable)
@@ -9,7 +9,7 @@ platform_check_image() {
 
        case "$board" in
        mbl)
-               mbl_do_platform_check $board "$1"
+               mbl_do_platform_check "$1"
                return $?;
                ;;
 
index d734751..2287e06 100644 (file)
@@ -1,36 +1,99 @@
 . /lib/functions.sh
 
-get_magic_at() {
-       local file="$1"
-       local pos="$2"
-       get_image "$file" | dd bs=1 count=2 skip="$pos" 2>/dev/null | hexdump -v -n 2 -e '1/1 "%02x"'
-}
+# copied from x86's platform.sh
 
 mbl_do_platform_check() {
-       local board="$1"
-       local file="$2"
-       local magic
+       local diskdev partdev diff
 
-       magic=$(get_magic_at "$file" 510)
+       [ "$#" -gt 1 ] && return 1
 
-       [ "$magic" != "55aa" ] && {
-               echo "Failed to verify MBR boot signature."
+       export_bootdevice && export_partdevice diskdev -2 || {
+               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
+
        return 0;
 }
 
 mbl_do_upgrade() {
+       local diskdev partdev diff
+
+       export_bootdevice && export_partdevice diskdev -2 || {
+               echo "Unable to determine upgrade device"
+               return 1
+       }
+
        sync
-       get_image "$1" | dd of=/dev/sda bs=2M conv=fsync
-       sleep 1
+
+       if [ "$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
+
+       #iterate over each partition from the image and write it to the boot disk
+       while read part start size; do
+               # root is /dev/sd[a|b]2 and not /dev/sd[a|b] this causes some problem
+               # one of which is this offset, I'm not sure what's the best fix, so
+               # here's a WA.
+               let part=$((part - 2))
+               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
 }
 
 mbl_copy_config() {
-       mkdir -p /boot
-       [ -f /boot/uImage ] || mount -t ext4 -o rw,noatime /dev/sda1 /boot
-       cp -af "$CONF_TAR" /boot/
-       sync
-       umount /boot
+       local partdev
+
+       # Same as above /dev/sd[a|b]2 is root, so /boot is -1
+       if export_partdevice partdev -1; then
+               mount -t ext4 -o rw,noatime "/dev/$partdev" /mnt
+               cp -af "$CONF_TAR" /mnt/
+               umount /mnt
+       fi
 }