target/linux/x86/base-files/lib/upgrade/platform.sh

   1 platform_export_bootpart() {
   2         local cmdline uuid disk
   3
   4         if read cmdline < /proc/cmdline; then
   5                 case "$cmdline" in
   6                         *block2mtd=*)
   7                                 disk="${cmdline##*block2mtd=}"
   8                                 disk="${disk%%,*}"
   9                         ;;
  10                         *root=*)
  11                                 disk="${cmdline##*root=}"
  12                                 disk="${disk%% *}"
  13                         ;;
  14                 esac
  15
  16                 case "$disk" in
  17                         PARTUUID=[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-02)
  18                                 uuid="${disk#PARTUUID=}"
  19                                 uuid="${uuid%-02}"
  20                                 for disk in /dev/[hsv]d[a-z]; do
  21                                         set -- $(dd if=$disk bs=1 skip=440 count=4 2>/dev/null | hexdump -v -e '4/1 "%02x "')
  22                                         if [ "$4$3$2$1" = "$uuid" ]; then
  23                                                 export BOOTPART="${disk}1"
  24                                                 return 0
  25                                         fi
  26                                 done
  27                         ;;
  28                         /dev/*)
  29                                 export BOOTPART="${disk%[0-9]}1"
  30                                 return 0
  31                         ;;
  32                 esac
  33         fi
  34
  35         return 1
  36 }
  37
  38 platform_check_image() {
  39         [ "$#" -gt 1 ] && return 1
  40
  41         case "$(get_magic_word "$1")" in
  42                 eb48|eb63) return 0;;
  43                 *)
  44                         echo "Invalid image type"
  45                         return 1
  46                 ;;
  47         esac
  48 }
  49
  50 platform_copy_config() {
  51         if [ -b "$BOOTPART" ]; then
  52                 mount -t ext4 -o rw,noatime "$BOOTPART" /mnt
  53                 cp -af "$CONF_TAR" /mnt/
  54                 umount /mnt
  55         fi
  56 }
  57
  58 get_partitions() { # <device> <filename>
  59         local disk="$1"
  60         local filename="$2"
  61
  62         if [ -b "$disk" -o -f "$disk" ]; then
  63                 echo "Reading partition table from $filename..."
  64                 partx -r "$disk" -gbo NR,START,SECTORS > "/tmp/partx.$filename"
  65         fi
  66 }
  67
  68 platform_do_upgrade() {
  69         platform_export_bootpart
  70         disk="${BOOTPART%[0-9]}"
  71
  72         if [ -b "$disk" ]; then
  73                 sync
  74                 if [ "$SAVE_PARTITIONS" = "1" ]; then
  75                         get_partitions "$disk" bootdisk
  76
  77
  78                         #get block size
  79                         sectors="$(partx -r $disk -gbo SECTORS --nr 1:1)"
  80                         size="$(partx -r $disk -gbo SIZE --nr 1:1)"
  81                         ibs="$(($size / $sectors))"
  82
  83                         #extract the boot sector from the image
  84                         get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b
  85
  86                         get_partitions /tmp/image.bs image
  87
  88                         #compare tables
  89                         diff="$(grep -F -x -v -f /tmp/partx.bootdisk /tmp/partx.image)"
  90                         if [ -n "$diff" ]; then
  91                                 echo "Partition layout is changed.  Full image will be written."
  92                                 ask_bool 0 "Abort" && exit
  93
  94                                 get_image "$@" | dd of="$disk" bs=4096 conv=fsync
  95                                 return 0
  96                         fi
  97
  98                         #iterate over each partition from the image and write it to the boot disk
  99                         while read part start size; do
 100                         echo "Writing image to $disk$part..."
 101                                 get_image "$@" | dd of="$disk$part" ibs="$ibs" obs=1M skip="$start" count="$size" conv=fsync
 102                         done < /tmp/partx.image
 103
 104                         #copy partition uuid
 105                         echo "Writing new UUID to $disk$part..."
 106                         get_image "$@" | dd of="$disk" bs=1 skip=440 count=4 seek=440 conv=fsync
 107                 else
 108                         get_image "$@" | dd of="$disk" bs=4096 conv=fsync
 109                 fi
 110
 111                 sleep 1
 112         fi
 113 }