x86: generalize partition discovery for sysupgrade

[librecmc/librecmc.git] / target / linux / x86 / base-files / lib / upgrade / platform.sh

diff --git a/target/linux/x86/base-files/lib/upgrade/platform.sh b/target/linux/x86/base-files/lib/upgrade/platform.sh
index 86696aec04de272019f5e16d931b6cd84aeb4d36..c8bc3f7f608fc82ee3afc049b64af3a740fd2c37 100644 (file)
--- a/target/linux/x86/base-files/lib/upgrade/platform.sh
+++ b/target/linux/x86/base-files/lib/upgrade/platform.sh
@@ -1,5 +1,21 @@
-platform_export_bootpart() {
-       local cmdline uuid disk
+platform_export_partdevice() {
+       local var="$1" offset="$2"
+       local uevent MAJOR MINOR DEVNAME DEVTYPE
+
+       for uevent in /sys/class/block/*/uevent; do
+               . "$uevent"
+               if [ $BOOTDEV_MAJOR = $MAJOR -a $(($BOOTDEV_MINOR + $offset)) = $MINOR -a -b "/dev/$DEVNAME" ]; then
+                       export "$var=$DEVNAME"
+                       return 0
+               fi
+       done
+
+       return 1
+}
+
+platform_export_bootdevice() {
+       local cmdline uuid disk uevent
+       local MAJOR MINOR DEVNAME DEVTYPE
 
        if read cmdline < /proc/cmdline; then
                case "$cmdline" in
@@ -17,19 +33,27 @@ platform_export_bootpart() {
                        PARTUUID=[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-02)
                                uuid="${disk#PARTUUID=}"
                                uuid="${uuid%-02}"
-                               for disk in /dev/[hsv]d[a-z]; do
+                               for disk in $(find /dev -type b); do
                                        set -- $(dd if=$disk bs=1 skip=440 count=4 2>/dev/null | hexdump -v -e '4/1 "%02x "')
                                        if [ "$4$3$2$1" = "$uuid" ]; then
-                                               export BOOTPART="${disk}1"
-                                               return 0
+                                               uevent="/sys/class/block/${disk##*/}/uevent"
+                                               break
                                        fi
                                done
                        ;;
                        /dev/*)
-                               export BOOTPART="${disk%[0-9]}1"
-                               return 0
+                               uevent="/sys/class/block/${disk##*/}/uevent"
                        ;;
                esac
+
+               if [ -e "$uevent" ]; then
+                       . "$uevent"
+
+                       export BOOTDEV_MAJOR=$MAJOR
+                       export BOOTDEV_MINOR=$MINOR
+
+                       return 0
+               fi
        fi
 
        return 1
@@ -48,8 +72,10 @@ platform_check_image() {
 }
 
 platform_copy_config() {
-       if [ -b "$BOOTPART" ]; then
-               mount -t ext4 -o rw,noatime "$BOOTPART" /mnt
+       local partdev
+
+       if platform_export_partdevice partdev 1; then
+               mount -t ext4 -o rw,noatime "/dev/$partdev" /mnt
                cp -af "$CONF_TAR" /mnt/
                umount /mnt
        fi
@@ -61,24 +87,44 @@ get_partitions() { # <device> <filename>
 
        if [ -b "$disk" -o -f "$disk" ]; then
                echo "Reading partition table from $filename..."
-               partx -r "$disk" -gbo NR,START,SECTORS > "/tmp/partx.$filename"
+
+               local magic="$(hexdump -v -n 2 -s 0x1FE -e '1/2 "0x%04X"' "$disk")"
+               if [ "$magic" != 0xAA55 ]; then
+                       echo "Invalid partition table on $disk"
+                       exit
+               fi
+
+               rm -f "/tmp/partmap.$filename"
+
+               local part
+               for part in 1 2 3 4; do
+                       set -- $(hexdump -v -n 12 -s "$((0x1B2 + $part * 16))" -e '3/4 "0x%08X "' "$disk")
+
+                       local type="$(($1 % 256))"
+                       local lba="$(($2))"
+                       local num="$(($3))"
+
+                       [ $type -gt 0 ] || continue
+
+                       printf "%2d %5d %7d\n" $part $lba $num >> "/tmp/partmap.$filename"
+               done
        fi
 }
 
 platform_do_upgrade() {
-       platform_export_bootpart
-       disk="${BOOTPART%[0-9]}"
+       local diskdev partdev ibs diff
 
-       if [ -b "$disk" ]; then
+       if platform_export_bootdevice && platform_export_partdevice diskdev 0; then
                sync
                if [ "$SAVE_PARTITIONS" = "1" ]; then
-                       get_partitions "$disk" bootdisk
-
+                       get_partitions "/dev/$diskdev" bootdisk
 
                        #get block size
-                       sectors="$(partx -r $disk -gbo SECTORS --nr 1:1)"
-                       size="$(partx -r $disk -gbo SIZE --nr 1:1)"
-                       ibs="$(($size / $sectors))"
+                       if [ -f "/sys/block/$diskdev/queue/physical_block_size" ]; then
+                               ibs="$(cat "/sys/block/$diskdev/queue/physical_block_size")"
+                       else
+                               ibs=512
+                       fi
 
                        #extract the boot sector from the image
                        get_image "$@" | dd of=/tmp/image.bs count=1 bs=512b
@@ -86,26 +132,30 @@ platform_do_upgrade() {
                        get_partitions /tmp/image.bs image
 
                        #compare tables
-                       diff="$(grep -F -x -v -f /tmp/partx.bootdisk /tmp/partx.image)"
+                       diff="$(grep -F -x -v -f /tmp/partmap.bootdisk /tmp/partmap.image)"
                        if [ -n "$diff" ]; then
                                echo "Partition layout is changed.  Full image will be written."
                                ask_bool 0 "Abort" && exit
 
-                               get_image "$@" | dd of="$disk" bs=4096 conv=fsync
+                               get_image "$@" | dd of="/dev/$diskdev" bs=4096 conv=fsync
                                return 0
                        fi
 
                        #iterate over each partition from the image and write it to the boot disk
                        while read part start size; do
-                       echo "Writing image to $disk$part..."
-                               get_image "$@" | dd of="$disk$part" ibs="$ibs" obs=1M skip="$start" count="$size" conv=fsync
-                       done < /tmp/partx.image
+                               if platform_export_partdevice partdev $part; then
+                                       echo "Writing image to /dev/$partdev..."
+                                       get_image "$@" | dd of="/dev/$partdev" ibs="$ibs" obs=1M skip="$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 $disk$part..."
-                       get_image "$@" | dd of="$disk" bs=1 skip=440 count=4 seek=440 conv=fsync
+                       echo "Writing new UUID to /dev/$diskdev..."
+                       get_image "$@" | dd of="/dev/$diskdev" bs=1 skip=440 count=4 seek=440 conv=fsync
                else
-                       get_image "$@" | dd of="$disk" bs=4096 conv=fsync
+                       get_image "$@" | dd of="/dev/$diskdev" bs=4096 conv=fsync
                fi
 
                sleep 1