From 821c0620738888d480819de064d908e5d71a1d23 Mon Sep 17 00:00:00 2001
From: Calin Crisan <ccrisan@gmail.com>
Date: Fri, 1 Feb 2019 23:14:03 +0200
Subject: [PATCH] fwupdate: add root partition relocation support

---
 board/common/overlay/sbin/fwupdate | 87 +++++++++++++++++++++++++++---
 1 file changed, 81 insertions(+), 6 deletions(-)

diff --git a/board/common/overlay/sbin/fwupdate b/board/common/overlay/sbin/fwupdate
index 2bdc879257..e249ff33e0 100755
--- a/board/common/overlay/sbin/fwupdate
+++ b/board/common/overlay/sbin/fwupdate
@@ -34,6 +34,8 @@ fi
 
 #### configuration ####
 
+set -a
+
 SYS_VERSION_FILE=/etc/version
 SYS_BOARD_FILE=/etc/board
 OS_CONF_FILE=/etc/init.d/os_conf
@@ -68,6 +70,7 @@ source ${SYS_VERSION_FILE}
 
 BOOT_DEV=$(mount | grep /boot | cut -d ' ' -f 1)
 ROOT_DEV=${BOOT_DEV:0:-1}2
+DATA_DEV=${BOOT_DEV:0:-1}3
 DISK_DEV=$(mount | grep /boot | cut -d ' ' -f 1)
 if [[ "${ROOT_DEV}" =~ ^([/a-z0-9]+)(p[0-9])$ ]]; then  # e.g. /dev/mmcblk0p2
     DISK_DEV=${BASH_REMATCH[1]}
@@ -78,6 +81,8 @@ else
     exit 1
 fi
 
+set +a
+
 
 #### versions ####
 
@@ -250,19 +255,19 @@ function do_extract() {
     
     # verify available partition space
     
-    fw_boot_info=$(fdisk --bytes -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}1")
+    fw_boot_info=$(fdisk -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}1")
     fw_boot_info=(${fw_boot_info})
     fw_boot_size=${fw_boot_info[3]}
 
-    fw_root_info=$(fdisk --bytes -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}2")
+    fw_root_info=$(fdisk -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}2")
     fw_root_info=(${fw_root_info})
     fw_root_size=${fw_root_info[3]}
     
-    disk_boot_info=$(fdisk --bytes -l -o device,start,end,size ${DISK_DEV} | grep ${BOOT_DEV})
+    disk_boot_info=$(fdisk -l -o device,start,end,size ${DISK_DEV} | grep ${BOOT_DEV})
     disk_boot_info=(${disk_boot_info})
     disk_boot_size=${disk_boot_info[3]}
     
-    disk_root_info=$(fdisk --bytes -l -o device,start,end,size ${DISK_DEV} | grep ${ROOT_DEV})
+    disk_root_info=$(fdisk -l -o device,start,end,size ${DISK_DEV} | grep ${ROOT_DEV})
     disk_root_info=(${disk_root_info})
     disk_root_size=${disk_root_info[3]}
     
@@ -318,12 +323,12 @@ function do_flash_boot() {
     mv /sbin/reboot /sbin/reboot.bak
     ln -s /bin/true /sbin/reboot
     
-    boot_info=$(fdisk --bytes -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}1")
+    boot_info=$(fdisk -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}1")
     boot_info=(${boot_info})
     boot_start=$((${boot_info[1]} / 2048))  # in MB
     boot_size=$((${boot_info[3]} / 1048576))  # in MB
 
-    root_info=$(fdisk --bytes -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}2")
+    root_info=$(fdisk -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}2")
     root_info=(${root_info})
     root_start=$((${root_info[1]} / 2048))  # in MB
     root_size=$((${root_info[3]} / 1048576))  # in MB
@@ -372,7 +377,77 @@ function flash_cleanup() {
 
 #### flash reboot ####
 
+function run_pre_upgrade() {
+    root_start=$(cat ${FW_DIR}/${ROOT_INFO_FILE} | cut -d ' ' -f 1)
+    tmp_mnt="/tmp/fwupdate_root"
+    loop="/dev/loop4"
+    pre_upgrade="${tmp_mnt}/usr/share/pre-upgrade/*"
+    
+    mkdir -p ${tmp_mnt}
+    losetup -o $((root_start * 1024 * 1024)) ${loop} ${FW_DIR}/${FW_FILE_EXTR}
+    mount ${loop} ${tmp_mnt}
+    if [[ -d ${pre_upgrade} ]]; then
+        for script in ${pre_upgrade}/*.sh; do
+            echo "running pre-upgrade script $(basename ${script})"
+            if [[ -x ${script} ]] && ! ${script}; then
+                # non-zero exit status of pre-upgrade script indicates that
+                # the upgrade process must not be continued
+                
+                echo "aborted by pre-upgrade script"
+                return 1
+            fi
+        done
+    fi
+
+    umount ${tmp_mnt}
+    losetup -d ${loop}
+}
+
+function reallocate_root_part() {
+    root_info=$(fdisk -l -o device,start,end,size ${DISK_DEV} | grep "${ROOT_DEV}")
+    root_info=(${root_info})
+
+    data_info=$(fdisk -l -o device,start,end,size ${DISK_DEV} | grep "${DATA_DEV}")
+    data_info=(${data_info})
+
+    fw_root_info=$(fdisk -l -o device,start,end,size ${FW_DIR}/${FW_FILE_EXTR} | grep "${FW_FILE_EXTR}2")
+    fw_root_info=(${fw_root_info})
+
+    if [[ ${root_info[1]} == ${fw_root_info[1]} ]] && 
+       [[ ${root_info[2]} == ${fw_root_info[2]} ]]; then
+
+        return  # all good
+    fi
+    
+    # check overlapping with data partition
+    if [[ ${fw_root_info[2]} -ge ${data_info[1]} ]]; then
+        echo "cannot reallocate root partition: will overlap with data"
+        return 1
+    fi
+
+    fdisk ${DISK_DEV} >/dev/null <<END
+d
+2
+n
+p
+2
+${new_root_info[1]}
+${new_root_info[2]}
+y
+w
+END
+    sync
+}
+
 function do_flash_reboot() {
+    if [[ ! -f ${FW_DIR}/${ROOT_INFO_FILE} ]]; then
+        echo "extracted firmware not present"
+        return 1
+    fi
+    
+    run_pre_upgrade || return 1
+    reallocate_root_part || return 1
+
     echo "preparing for reboot..."
 
     board=$(cat ${SYS_BOARD_FILE})