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/*; do
  21                                         [ -b "$disk" ] || continue
  22                                         set -- $(dd if=$disk bs=1 skip=440 count=4 2>/dev/null | hexdump -v -e '4/1 "%02x "')
  23                                         if [ "$4$3$2$1" = "$uuid" ]; then
  24                                                 export BOOTPART="${disk}1"
  25                                                 return 0
  26                                         fi
  27                                 done
  28                         ;;
  29                         /dev/*)
  30                                 export BOOTPART="${disk%[0-9]}1"
  31                                 return 0
  32                         ;;
  33                 esac
  34         fi
  35
  36         return 1
  37 }
  38
  39 platform_check_image() {
  40         [ "$#" -gt 1 ] && return 1
  41
  42         case "$(get_magic_word "$1")" in
  43                 eb48|eb63) return 0;;
  44                 *)
  45                         echo "Invalid image type"
  46                         return 1
  47                 ;;
  48         esac
  49 }
  50
  51 platform_copy_config() {
  52         if [ -b "$BOOTPART" ]; then
  53                 mount -t ext4 -o rw,noatime "$BOOTPART" /mnt
  54                 cp -af "$CONF_TAR" /mnt/
  55                 umount /mnt
  56         fi
  57 }
  58
  59 get_partitions() { # <device> <filename>
  60         local disk="$1"
  61         local filename="$2"
  62
  63         if [ -b "$disk" -o -f "$disk" ]; then
  64                 echo "Reading partition table from $filename..."
  65
  66                 local magic="$(hexdump -v -n 2 -s 0x1FE -e '1/2 "0x%04X"' "$disk")"
  67                 if [ "$magic" != 0xAA55 ]; then
  68                         echo "Invalid partition table on $disk"
  69                         exit
  70                 fi
  71
  72                 rm -f "/tmp/partmap.$filename"
  73
  74                 local part
  75                 for part in 1 2 3 4; do
  76                         set -- $(hexdump -v -n 12 -s "$((0x1B2 + $part * 16))" -e '3/4 "0x%08X "' "$disk")
  77
  78                         local type="$(($1 % 256))"
  79                         local lba="$(($2))"
  80                         local num="$(($3))"
  81
  82                         [ $type -gt 0 ] || continue
  83
  84                         printf "%2d %5d %7d\n" $part $lba $num >> "/tmp/partmap.$filename"
  85                 done
  86         fi
  87 }
  88
  89 platform_do_upgrade() {
  90         platform_export_bootpart
  91         disk="${BOOTPART%[0-9]}"
  92
  93         if [ -b "$disk" ]; then
  94                 sync
  95                 if [ "$SAVE_PARTITIONS" = "1" ]; then
  96                         get_partitions "$disk" bootdisk
  97
  98
  99                         #get block size
 100                         if [ -f "/sys/block/${disk##*/}/queue/physical_block_size" ]; then
 101                                 ibs="$(cat "/sys/block/${disk##*/}/queue/physical_block_size")"
 102                         else
 103                                 ibs=512
 104                         fi
 105
 106                         #extract the boot sector from the image
 107                         get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b
 108
 109                         get_partitions /tmp/image.bs image
 110
 111                         #compare tables
 112                         diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)"
 113                         if [ -n "$diff" ]; then
 114                                 echo "Partition layout is changed.  Full image will be written."
 115                                 ask_bool 0 "Abort" && exit
 116
 117                                 get_image "$@" | dd of="$disk" bs=4096 conv=fsync
 118                                 return 0
 119                         fi
 120
 121                         #iterate over each partition from the image and write it to the boot disk
 122                         while read part start size; do
 123                         echo "Writing image to $disk$part..."
 124                                 get_image "$@" | dd of="$disk$part" ibs="$ibs" obs=1M skip="$start" count="$size" conv=fsync
 125                         done < /tmp/partmap.image
 126
 127                         #copy partition uuid
 128                         echo "Writing new UUID to $disk$part..."
 129                         get_image "$@" | dd of="$disk" bs=1 skip=440 count=4 seek=440 conv=fsync
 130                 else
 131                         get_image "$@" | dd of="$disk" bs=4096 conv=fsync
 132                 fi
 133
 134                 sleep 1
 135         fi
 136 }