arm-autonomy, xenguest-manager: Guest creation failure cleanup

When the guest creation process fails, we need to perform a proper
cleanup on the system, like removing configuration files and detaching
the disk previously attached to Xen.

This patch also adds an extra failure condition when the partition
assigned to guests is already formatted with a filesystem and it is not
a lvm partition.

Change-Id: I36087bf95fb8ff093160a6df406920fa5f293e09
Issue-Id: SCM-996
Signed-off-by: Diego Sueiro <diego.sueiro@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-autonomy/recipes-extended/xenguest/files/xenguest-manager

@@ -56,10 +56,14 @@ EOF
 
 function xenguest_volume_init()
 {
+    # Return:
+    # 0 - success
+    # 1 - failure
+
     if [ -z "${XENGUEST_VOLUME_DEVICE:-}" -o \
         ! -b ${XENGUEST_VOLUME_DEVICE:-} ]; then
         echo "${PREF} Invalid volume device in configuration: ${XENGUEST_VOLUME_DEVICE:-}"
-        exit 1
+        return 1
     fi
 
     if [ -z "${XENGUEST_VOLUME_NAME:-}" ]; then
@@ -69,14 +73,26 @@ function xenguest_volume_init()
 
     pvs ${XENGUEST_VOLUME_DEVICE} > /dev/null 2>&1
     if [ $? -ne 0 ]; then
-        echo "${PREF} Initialize lvm on ${XENGUEST_VOLUME_DEVICE}"
+        # Check if there is no filesystem in the block device
-        echo "pvcreate -f ${XENGUEST_VOLUME_DEVICE}" >> ${LOGFILE} 2>&1
+        echo "lsblk -n -o FSTYPE ${XENGUEST_VOLUME_DEVICE}" >> ${LOGFILE} 2>&1
-        pvcreate -f ${XENGUEST_VOLUME_DEVICE} >> ${LOGFILE} 2>&1
+        filesystem=$(lsblk -n -o FSTYPE ${XENGUEST_VOLUME_DEVICE} 2>> ${LOGFILE})
-        if [ $? -ne 0 ]; then
+        if [[ $? -eq 0 && -z "$filesystem" ]]; then
-            echo "${PREF} Error"
+            echo "${PREF} Initialize lvm on ${XENGUEST_VOLUME_DEVICE}"
-            exit 1
+            echo "pvcreate -f ${XENGUEST_VOLUME_DEVICE}" >> ${LOGFILE} 2>&1
+            pvcreate -f ${XENGUEST_VOLUME_DEVICE} >> ${LOGFILE} 2>&1
+            if [ $? -ne 0 ]; then
+                echo "${PREF} Error: initialing lvm on " \
+                     "${XENGUEST_VOLUME_DEVICE} failed." | tee -a ${LOGFILE}
+                return 1
+            fi
+        else
+            [ -z "$filesystem" ] || \
+                echo "${PREF} Error: The ${XENGUEST_VOLUME_DEVICE} is already " \
+                     "formatted as $filesystem." | tee -a ${LOGFILE}
+            return 1
         fi
     fi
+
     vgs ${XENGUEST_VOLUME_NAME} > /dev/null 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Create ${XENGUEST_VOLUME_NAME} volume"
@@ -85,10 +101,13 @@ function xenguest_volume_init()
         vgcreate ${XENGUEST_VOLUME_NAME} ${XENGUEST_VOLUME_DEVICE} \
             >> ${LOGFILE} 2>&1
         if [ $? -ne 0 ]; then
-            echo "${PREF} Error"
+            echo "${PREF} Error: creating ${XENGUEST_VOLUME_NAME} volume " \
-            exit 1
+                 "failed."  | tee -a ${LOGFILE}
+            return 1
         fi
     fi
+
+    return 0
 }
 
 # Detach a disk we attached to xen
@@ -102,12 +121,21 @@ function xenguest_detach_disk()
         >> ${LOGFILE} 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Error detaching partition ${part}"
-        exit 1
+        return 1
     fi
 }
 
 function xenguest_disk_init()
 {
+    # Inputs:
+    # $1 - guestname
+    # $2 - guestfile
+    #
+    # Outputs:
+    # 0 - success
+    # 1 - failed at guest disk preparation
+    # 2 - failed at guest disk creation
+
     guestname="$1"
     guestfile="$2"
     devname="/dev/${XENGUEST_VOLUME_NAME}/${guestname}"
@@ -119,12 +147,16 @@ function xenguest_disk_init()
         return
     fi
 
-    echo "${PREF} Create ${guestname} disk"
+    echo "${PREF} Create ${guestname} disk."
 
     # Init our volume
-    xenguest_volume_init
+    xenguest_volume_init ${guestname}
+    if [ $? -ne 0 ]; then
+        return 1
+    fi
 
-    echo "${PREF} Create hard drive for ${guestname}"
+    echo "${PREF} Create hard drive for ${guestname}." \
+         "This might take a while..."
 
 
     # Remove volume if it already exist
@@ -135,7 +167,7 @@ function xenguest_disk_init()
         lvremove -y ${devname} >> ${LOGFILE} 2>&1
         if [ $? -ne 0 ]; then
             echo "${PREF} Error removing volume ${guestname}"
-            exit 1
+            return 1
         fi
     fi
 
@@ -146,7 +178,7 @@ function xenguest_disk_init()
         >> ${LOGFILE} 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Error creating volume ${guestname}"
-        exit 1
+        return 1
     fi
 
     # Add partition table
@@ -154,7 +186,7 @@ function xenguest_disk_init()
     parted -s ${devname} mklabel msdos >> ${LOGFILE} 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Error creating partition table on ${guestname}"
-        exit 1
+        return 1
     fi
 
     # Setup disk name in xen configuration
@@ -164,7 +196,7 @@ function xenguest_disk_init()
         --xen-disk=${devname} >> ${LOGFILE} 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Error setting disk in xen configuration"
-        exit 1
+        return 1
     fi
 
     # Create partitions
@@ -197,7 +229,7 @@ function xenguest_disk_init()
                 ${partend} >> ${LOGFILE} 2>&1
             if [ $? -ne 0 ]; then
                 echo "${PREF} Error adding partition ${part}"
-                exit 1
+                return 1
             fi
 
             # Set next partition start to current partition end
@@ -219,7 +251,7 @@ function xenguest_disk_init()
                     *)
                         echo "${PREF} partition ${part} of ${guestname}" \
                             "fstype is invalid: ${fstype}"
-                        exit 1
+                        return 1
                         ;;
                 esac
             else
@@ -231,7 +263,7 @@ function xenguest_disk_init()
             xl block-attach 0 phy:${devname} xvda w >> ${LOGFILE} 2>&1
             if [ $? -ne 0 ]; then
                 echo "${PREF} Error attaching partition ${part}"
-                exit 1
+                return 1
             fi
 
 
@@ -247,8 +279,7 @@ function xenguest_disk_init()
 
             if [ ! -b /dev/xvda${part} ]; then
                 echo "${PREF} Partition ${part} creation error"
-                xenguest_detach_disk
+                return 2
-                exit 1
             fi
 
             if [ -n "${formatcmd}" ]; then
@@ -256,8 +287,7 @@ function xenguest_disk_init()
                 ${formatcmd} /dev/xvda${part}
                 if [ $? -ne 0 ]; then
                     echo "${PREF} Cannot create partition ${part} FS"
-                    xenguest_detach_disk
+                    return 2
-                    exit 1
                 fi
             fi
 
@@ -277,8 +307,7 @@ function xenguest_disk_init()
                         *)
                             # invalid/unknown compression type
                             echo "${PREF} Invalid file format in disk ${content}"
-                            xenguest_detach_disk
+                            return 2
-                            exit 1
                             ;;
                     esac
                     # dd into partition
@@ -288,8 +317,7 @@ function xenguest_disk_init()
                         | ${decompress} | dd of=/dev/xvda${part} >> ${LOGFILE} 2>&1
                     if [ $? -ne 0 ]; then
                         echo "${PREF} Cannot populate partition ${part}"
-                        xenguest_detach_disk
+                        return 2
-                        exit 1
                     fi
                     ;;
                 *.tar*)
@@ -310,8 +338,7 @@ function xenguest_disk_init()
                         *)
                             # invalid/unknown tar type
                             echo "${PREF} Invalid file format in disk ${content}"
-                            xenguest_detach_disk
+                            return 2
-                            exit 1
                             ;;
                     esac
 
@@ -321,9 +348,8 @@ function xenguest_disk_init()
                     mount /dev/xvda${part} ${mntdir} >> ${LOGFILE} 2>&1
                     if [ $? -ne 0 ]; then
                         echo "${PREF} Cannot mount partition ${part}"
-                        xenguest_detach_disk
                         rm -rf ${mntdir}
-                        exit 1
+                        return 2
                     fi
 
                     # tar and unmount
@@ -336,16 +362,14 @@ function xenguest_disk_init()
                         echo "${PREF} Cannot populate partition ${part}"
                         umount ${mntdir}
                         rm -rf ${mntdir}
-                        xenguest_detach_disk
+                        return 2
-                        exit 1
                     fi
                     echo "umount ${mntdir}" >> ${LOGFILE} 2>&1
                     umount ${mntdir} >> ${LOGFILE} 2>&1
                     if [ $? -ne 0 ]; then
                         echo "${PREF} Error unmounting ${part}"
-                        xenguest_detach_disk
                         rm -rf ${mntdir}
-                        exit 1
+                        return 2
                     fi
                     rm -rf ${mntdir}
                     ;;
@@ -356,6 +380,9 @@ function xenguest_disk_init()
 
             # Detach disk
             xenguest_detach_disk
+            if [ $? -ne 0 ]; then
+                return 1
+            fi
         fi
     done
 
@@ -392,10 +419,21 @@ function xenguest_guest_create()
         --xen-name=${guestname} >> ${LOGFILE} 2>&1
     if [ $? -ne 0 ]; then
         echo "${PREF} Error setting guest name"
+        xenguest_guest_remove ${guestname}
         exit 1
     fi
 
     xenguest_disk_init ${guestname} ${guestfile}
+    disk_init_status=$?
+    if [ $disk_init_status -ne 0 ]; then
+        echo "${PREF} Error: ${guestname} disk creation failed."
+        if [ $disk_init_status -eq 2 ]; then
+            xenguest_detach_disk
+        fi
+        xenguest_guest_remove ${guestname}
+        exit 1
+    fi
+
 }
 
 function xenguest_guest_remove()
@@ -408,6 +446,7 @@ function xenguest_guest_remove()
     lvs ${XENGUEST_VOLUME_NAME}/${guestname} >> ${LOGFILE} 2>&1
     if [ $? -eq 0 ]; then
         # Remove guest volume
+        echo "${PREF} Removing ${guestname} volume. This might take a while..."
         echo "lvremove -y ${devname}" >> ${LOGFILE} 2>&1
         lvremove -y ${devname} >> ${LOGFILE} 2>&1
         if [ $? -ne 0 ]; then
@@ -417,6 +456,7 @@ function xenguest_guest_remove()
     fi
 
     # remove guest files
+    echo "${PREF} Removing ${guestname} configuration files."
     rm -rf ${XENGUEST_CONF_BASE}/guests/${guestname}
 }
 
@@ -602,6 +642,7 @@ case ${cmd} in
         fi
 
         xenguest_guest_create ${guestfile} ${guestname}
+        echo "${PREF} ${guestname} created."
         ;;
     remove)
         guestname="${arg1:-}"
@@ -619,6 +660,7 @@ case ${cmd} in
             fi
         fi
         xenguest_guest_remove ${guestname}
+        echo "${PREF} ${guestname} removed."
         ;;
     start)
         guestname="${arg1:-}"

meta-arm-autonomy/recipes-extended/xenguest/xenguest-manager.bb

@@ -46,7 +46,7 @@ do_install() {
 }
 
 # Things that we need on the target
-RDEPENDS_${PN} += "bash tar xenguest-mkimage lvm2 xen-tools parted e2fsprogs"
+RDEPENDS_${PN} += "bash tar xenguest-mkimage lvm2 xen-tools parted e2fsprogs dosfstools"
 
 FILES_${PN} += "${bindir}/xenguest-manager \
                ${sysconfdir}/xenguest"