Use compressed squashfs for kernel (#1418)

* Add squashfs with LZ4 and LZO compression to Barebox

* Add squashfs with LZO compression to U-Boot

* Use squashfs for Linux kernel partition

Generate a squashfs image with LZO compression for the Linux kernel
partition. Adjust the boot scripts to be file system independent commands
to boot from squashfs.

buildroot-external/scripts/hdd-image.sh

@@ -89,14 +89,7 @@ function create_kernel_image() {
 
     # Make image
     rm -f "${kernel_img}"
-    truncate --size="${KERNEL_SIZE}" "${kernel_img}"
-    mkfs.ext4 -L "hassos-kernel" -E lazy_itable_init=0,lazy_journal_init=0 -O ^64bit "${kernel_img}"
-
-    # Mount / init file structs
-    sudo mkdir -p /mnt/data/
-    sudo mount -o loop "${kernel_img}" /mnt/data
-    sudo cp "${kernel}" /mnt/data/
-    sudo umount /mnt/data
+    mksquashfs "${kernel}" "${kernel_img}" -comp lzo
 }
 
 

buildroot-external/scripts/name.sh

@@ -21,7 +21,7 @@ function path_spl_img() {
 }
 
 function path_kernel_img() {
-    echo "${BINARIES_DIR}/kernel.ext4"
+    echo "${BINARIES_DIR}/kernel.img"
 }
 
 function path_boot_img() {

buildroot-external/scripts/ota.sh

@@ -5,7 +5,7 @@ function create_ota_update() {
     local ota_file="$(hassos_image_name raucb)"
     local rauc_folder="${BINARIES_DIR}/rauc"
     local boot="${BINARIES_DIR}/boot.vfat"
-    local kernel="${BINARIES_DIR}/kernel.ext4"
+    local kernel="${BINARIES_DIR}/kernel.img"
     local rootfs="${BINARIES_DIR}/rootfs.squashfs"
     local spl="${BINARIES_DIR}/spl.img"
     local key="/build/key.pem"
@@ -21,7 +21,7 @@ function create_ota_update() {
     rm -rf "${rauc_folder}" "${ota_file}"
     mkdir -p "${rauc_folder}"
 
-    cp -f "${kernel}" "${rauc_folder}/kernel.ext4"
+    cp -f "${kernel}" "${rauc_folder}/kernel.img"
     cp -f "${boot}" "${rauc_folder}/boot.vfat"
     cp -f "${rootfs}" "${rauc_folder}/rootfs.img"
     cp -f "${BR2_EXTERNAL_HASSOS_PATH}/ota/rauc-hook" "${rauc_folder}/hook"
@@ -37,7 +37,7 @@ function create_ota_update() {
         echo "filename=boot.vfat"
         echo "hooks=install"
         echo "[image.kernel]"
-        echo "filename=kernel.ext4"
+        echo "filename=kernel.img"
         echo "[image.rootfs]"
         echo "filename=rootfs.img"
     ) > "${rauc_folder}/manifest.raucm"

buildroot-external/scripts/rauc.sh

@@ -43,7 +43,7 @@ function _write_rauc_system() {
     (
         echo "[slot.kernel.${slot_num}]"
         echo "device=/dev/disk/by-partlabel/hassos-kernel${slot_num}"
-        echo "type=ext4"
+        echo "type=raw"
         echo "bootname=${slot_name}"
 
         echo "[slot.rootfs.${slot_num}]"