base-files: fix and clean up nand sysupgrade code

- Never return from 'nand_do_upgrade', not even in case of errors, as that
  would cause execution of sysupgrade code not intended for NAND devices.
- Unify handling of sysupgrade success and failure.
- Detect and report more error conditions.
- Fix outdated/incorrect/unclear comments.

Signed-off-by: Rodrigo Balerdi <lanchon@gmail.com>

diff --git a/package/base-files/files/lib/upgrade/nand.sh b/package/base-files/files/lib/upgrade/nand.sh
index c9960bf9d44d1d2375b20398e56465cca54e1582..76a984483e0ae47b705a0c59f4e20b23e27ca42e 100644 (file)
--- a/package/base-files/files/lib/upgrade/nand.sh
+++ b/package/base-files/files/lib/upgrade/nand.sh
@@ -231,63 +231,49 @@ nand_upgrade_prepare_ubi() {
        return 0
 }
 
-nand_do_upgrade_success() {
-       local conf_tar="/tmp/sysupgrade.tgz"
-       if { [ ! -f "$conf_tar" ] || nand_restore_config "$conf_tar"; } && sync; then
-               echo "sysupgrade successful"
-       fi
-       umount -a
-       reboot -f
-}
-
-# Flash the UBI image to MTD partition
+# Write the UBI image to MTD ubi partition
 nand_upgrade_ubinized() {
        local ubi_file="$1"
-       local mtdnum="$(find_mtd_index "$CI_UBIPART")"
 
+       local mtdnum="$( find_mtd_index "$CI_UBIPART" )"
        if [ ! "$mtdnum" ]; then
-               echo "cannot find mtd device $CI_UBIPART"
-               umount -a
-               reboot -f
+               echo "cannot find ubi mtd partition $CI_UBIPART"
+               return 1
        fi
 
        local mtddev="/dev/mtd${mtdnum}"
        ubidetach -p "${mtddev}" || :
-       ubiformat "${mtddev}" -y -f "${ubi_file}"
-       ubiattach -p "${mtddev}"
-
-       nand_do_upgrade_success
+       ubiformat "${mtddev}" -y -f "${ubi_file}" && ubiattach -p "${mtddev}"
 }
 
-# Write the UBIFS image to UBI volume
+# Write the UBIFS image to UBI rootfs volume
 nand_upgrade_ubifs() {
        local rootfs_length=$( (cat $1 | wc -c) 2> /dev/null)
 
-       nand_upgrade_prepare_ubi "$rootfs_length" "ubifs" "" ""
+       nand_upgrade_prepare_ubi "$rootfs_length" "ubifs" "" "" || return 1
 
        local ubidev="$( nand_find_ubi "$CI_UBIPART" )"
        local root_ubivol="$(nand_find_volume $ubidev "$CI_ROOTPART")"
        ubiupdatevol /dev/$root_ubivol -s $rootfs_length $1
-
-       nand_do_upgrade_success
 }
 
+# Write the FIT image to UBI kernel volume
 nand_upgrade_fit() {
        local fit_file="$1"
        local fit_length="$(wc -c < "$fit_file")"
 
-       nand_upgrade_prepare_ubi "" "" "$fit_length" "1"
+       nand_upgrade_prepare_ubi "" "" "$fit_length" "1" || return 1
 
        local fit_ubidev="$(nand_find_ubi "$CI_UBIPART")"
        local fit_ubivol="$(nand_find_volume $fit_ubidev "$CI_KERNPART")"
        ubiupdatevol /dev/$fit_ubivol -s $fit_length $fit_file
-
-       nand_do_upgrade_success
 }
 
+# Write images in the TAR file to MTD partitions and/or UBI volumes as required
 nand_upgrade_tar() {
        local tar_file="$1"
 
+       # WARNING: This fails if tar contains more than one 'sysupgrade-*' directory.
        local board_dir="$(tar tf "$tar_file" | grep -m 1 '^sysupgrade-.*/$')"
        board_dir="${board_dir%/}"
 
@@ -315,7 +301,7 @@ nand_upgrade_tar() {
                fi
        fi
        local has_env=0
-       nand_upgrade_prepare_ubi "$rootfs_length" "$rootfs_type" "$ubi_kernel_length" "$has_env"
+       nand_upgrade_prepare_ubi "$rootfs_length" "$rootfs_type" "$ubi_kernel_length" "$has_env" || return 1
 
        local ubidev="$( nand_find_ubi "$CI_UBIPART" )"
        if [ "$rootfs_length" ]; then
@@ -334,16 +320,14 @@ nand_upgrade_tar() {
                fi
        fi
 
-       nand_do_upgrade_success
+       return 0
 }
 
-# Recognize type of passed file and start the upgrade process
-nand_do_upgrade() {
+nand_do_flash_file() {
        local file_type=$(identify "$1")
 
        [ ! "$(find_mtd_index "$CI_UBIPART")" ] && CI_UBIPART=rootfs
 
-       sync
        case "$file_type" in
                "fit")          nand_upgrade_fit "$1";;
                "ubi")          nand_upgrade_ubinized "$1";;
@@ -352,14 +336,34 @@ nand_do_upgrade() {
        esac
 }
 
-# Check if passed file is a valid one for NAND sysupgrade. Currently it accepts
-# 3 types of files:
-# 1) UBI - should contain an ubinized image, header is checked for the proper
-#    MAGIC
-# 2) UBIFS - should contain UBIFS partition that will replace "rootfs" volume,
-#    header is checked for the proper MAGIC
-# 3) TAR - archive has to include "sysupgrade-BOARD" directory with a non-empty
-#    "CONTROL" file (at this point its content isn't verified)
+nand_do_restore_config() {
+       local conf_tar="/tmp/sysupgrade.tgz"
+       [ ! -f "$conf_tar" ] || nand_restore_config "$conf_tar"
+}
+
+# Recognize type of passed file and start the upgrade process
+nand_do_upgrade() {
+       sync
+       if nand_do_flash_file "$1" && nand_do_restore_config && sync; then
+               echo "sysupgrade successful"
+               umount -a
+               reboot -f
+       fi
+
+       sync
+       echo "sysupgrade failed"
+       # Should we reboot or bring up some failsafe mode instead?
+       umount -a
+       reboot -f
+}
+
+# Check if passed file is a valid one for NAND sysupgrade.
+# Currently it accepts 4 types of files:
+# 1) UBI: a ubinized image containing required UBI volumes.
+# 2) UBIFS: a UBIFS rootfs volume image.
+# 3) FIT: a FIT image containing kernel and rootfs.
+# 4) TAR: an archive that includes directory "sysupgrade-${BOARD_NAME}" containing
+#         a non-empty "CONTROL" file and required partition and/or volume images.
 #
 # You usually want to call this function in platform_check_image.
 #