<p dir="ltr">Rob, I'll not judge the merit of keeping the previous position table, but I guess dd might be enough for saving/restore partitions (I guess only msdos is used). dd and /proc/partitions might replace sfdisk.</p>
<br><div class="gmail_quote"><div dir="ltr">Em sáb, 16 de jan de 2016 23:22, Rob Mosher <<a href="mailto:nyt-openwrt@countercultured.net">nyt-openwrt@countercultured.net</a>> escreveu:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">This patch will save the partition table before an upgrade.<br>
If the installed image has not changed the partition structure<br>
the saved table will be restored, ensuring any user created<br>
partitions will be present after the upgrade.<br>
<br>
An option is added to sysupgrade to disable this feature.<br>
<br>
Signed-off-by: Rob Mosher <<a href="mailto:nyt-openwrt@countercultured.net" target="_blank">nyt-openwrt@countercultured.net</a>><br>
---<br>
 package/base-files/files/lib/upgrade/common.sh     |  1 +<br>
 package/base-files/files/sbin/sysupgrade           |  3 ++<br>
 target/linux/x86/Makefile                          |  2 +<br>
 .../linux/x86/base-files/lib/upgrade/platform.sh   | 45 ++++++++++++++++++++++<br>
 4 files changed, 51 insertions(+)<br>
<br>
diff --git a/package/base-files/files/lib/upgrade/common.sh b/package/base-files/files/lib/upgrade/common.sh<br>
index 761b4c1..aed7f8e 100644<br>
--- a/package/base-files/files/lib/upgrade/common.sh<br>
+++ b/package/base-files/files/lib/upgrade/common.sh<br>
@@ -67,6 +67,7 @@ run_ramfs() { # <command> [...]<br>
        install_bin /usr/sbin/ubirsvol<br>
        install_bin /usr/sbin/ubirmvol<br>
        install_bin /usr/sbin/ubimkvol<br>
+       install_bin /usr/sbin/sfdisk<br>
        for file in $RAMFS_COPY_BIN; do<br>
                install_bin ${file//:/ }<br>
        done<br>
diff --git a/package/base-files/files/sbin/sysupgrade b/package/base-files/files/sbin/sysupgrade<br>
index 93f0749..2f441f8 100755<br>
--- a/package/base-files/files/sbin/sysupgrade<br>
+++ b/package/base-files/files/sbin/sysupgrade<br>
@@ -10,6 +10,7 @@ export INTERACTIVE=0<br>
 export VERBOSE=1<br>
 export SAVE_CONFIG=1<br>
 export SAVE_OVERLAY=0<br>
+export SAVE_PARTITIONS=1<br>
 export DELAY=<br>
 export CONF_IMAGE=<br>
 export CONF_BACKUP_LIST=0<br>
@@ -29,6 +30,7 @@ while [ -n "$1" ]; do<br>
                -q) export VERBOSE="$(($VERBOSE - 1))";;<br>
                -n) export SAVE_CONFIG=0;;<br>
                -c) export SAVE_OVERLAY=1;;<br>
+               -p) export SAVE_PARTITIONS=0;;<br>
                -b|--create-backup) export CONF_BACKUP="$2" NEED_IMAGE=1; shift;;<br>
                -r|--restore-backup) export CONF_RESTORE="$2" NEED_IMAGE=1; shift;;<br>
                -l|--list-backup) export CONF_BACKUP_LIST=1; break;;<br>
@@ -62,6 +64,7 @@ upgrade-option:<br>
        -i           interactive mode<br>
        -c           attempt to preserve all changed files in /etc/<br>
        -n           do not save configuration over reflash<br>
+       -p           do not attempt to restore the partition table after flash.<br>
        -T | --test<br>
                     Verify image and config .tar.gz but do not actually flash.<br>
        -F | --force<br>
diff --git a/target/linux/x86/Makefile b/target/linux/x86/Makefile<br>
index e4bc0d9..e5b4378 100644<br>
--- a/target/linux/x86/Makefile<br>
+++ b/target/linux/x86/Makefile<br>
@@ -13,6 +13,8 @@ FEATURES:=squashfs ext4 vdi vmdk pcmcia targz<br>
 SUBTARGETS=generic xen_domu ep80579 geode kvm_guest 64<br>
 MAINTAINER:=Felix Fietkau <<a href="mailto:nbd@openwrt.org" target="_blank">nbd@openwrt.org</a>><br>
<br>
+DEFAULT_PACKAGES += sfdisk<br>
+<br>
 KERNEL_PATCHVER:=4.4<br>
<br>
 KERNELNAME:=bzImage<br>
diff --git a/target/linux/x86/base-files/lib/upgrade/platform.sh b/target/linux/x86/base-files/lib/upgrade/platform.sh<br>
index 73ab5ef..7f5a2b1 100644<br>
--- a/target/linux/x86/base-files/lib/upgrade/platform.sh<br>
+++ b/target/linux/x86/base-files/lib/upgrade/platform.sh<br>
@@ -55,12 +55,57 @@ platform_copy_config() {<br>
        fi<br>
 }<br>
<br>
+save_bootparts() {<br>
+       disk=${BOOTPART%[0-9]}<br>
+       if [ -b $disk ]; then<br>
+               echo "Backing up partition table..."<br>
+               sfdisk -d $disk > /tmp/sfdisk.before<br>
+               grep size= /tmp/sfdisk.before | grep -E -v 'size=\s+0,' > /tmp/sfdisk.before.nonempty<br>
+       fi<br>
+}<br>
+<br>
+restore_bootparts() {<br>
+       disk=${BOOTPART%[0-9]}<br>
+       if [ -b $disk ]; then<br>
+               sfdisk -d $disk > /tmp/sfdisk.after<br>
+               grep size= /tmp/sfdisk.after | grep -E -v 'size=\s+0,' > /tmp/sfdisk.after.nonempty<br>
+               before=$(cat /tmp/sfdisk.before.nonempty)<br>
+               after=$(cat /tmp/sfdisk.after.nonempty)<br>
+<br>
+               #ensure we have both partition tables<br>
+               if [ -z "$before" -o -z "$after" ]; then<br>
+                       echo "Could not read partition table"<br>
+                       return 1<br>
+               fi<br>
+<br>
+               #if nothing changed, we do not need to restore<br>
+               if [ "$before" = "$after" ]; then<br>
+                       echo "Parition layout unchanged"<br>
+                       return 0<br>
+               fi<br>
+<br>
+               diff=$(grep -F -x -v -f /tmp/sfdisk.before.nonempty /tmp/sfdisk.after.nonempty)<br>
+<br>
+               #if partition layout changed, do not restore<br>
+               if [ -n "$diff" ]; then<br>
+                       echo "Partition layout changed, not restoring."<br>
+                       return 1<br>
+               fi<br>
+<br>
+               echo "Restoring partition table..."<br>
+               sfdisk $disk --force < /tmp/sfdisk.before >&/dev/null<br>
+       fi<br>
+}<br>
+<br>
 platform_do_upgrade() {<br>
        platform_export_bootpart<br>
<br>
        if [ -b "${BOOTPART%[0-9]}" ]; then<br>
                sync<br>
+               [ $SAVE_PARTITIONS = "1" ] && save_bootparts<br>
                get_image "$@" | dd of="${BOOTPART%[0-9]}" bs=4096 conv=fsync<br>
                sleep 1<br>
+               [ $SAVE_PARTITIONS = "1" ] && restore_bootparts<br>
        fi<br>
 }<br>
+<br>
--<br>
2.1.4<br>
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</blockquote></div><div dir="ltr">-- <br></div><p dir="ltr">Luiz Angelo Daros de Luca<br>
<a href="mailto:luizluca@gmail.com">luizluca@gmail.com</a></p>