diff --git a/overlay/usr/libexec/init-storage b/overlay/usr/libexec/init-storage
index c4685dc..eb87e4f 100755
--- a/overlay/usr/libexec/init-storage
+++ b/overlay/usr/libexec/init-storage
@@ -29,6 +29,22 @@ copy_var() {
 
 format_dev() {
     dev="$1"
+    partno=$(partition_number "${dev}")
+    if [ -n "${partno}" ]; then
+        disk="$(get_disk "${dev}")"
+        if [ -n "${disk}" ]; then
+            printf 'Resizing partition %d on disk %s\n' \
+                "${partno}" \
+                "${disk}" \
+                >&2
+            resize_partition "${disk}" "${partno}"
+        else
+            printf 'Could not find disk for device %s\n' \
+                "${dev}" \
+                >&2
+        fi
+    fi
+
     printf 'Creating BTRFS filesystem on %s\n' "${dev}"
     mkfs.btrfs "${dev}" || exit
 
@@ -41,12 +57,37 @@ format_dev() {
     umount "${dev}" || exit
 }
 
+get_disk() {
+    _syspath=/sys/class/block/${1##*/}
+    [ -d "${_syspath}" ] || return 1
+    if [ ! -f "${_syspath}"/partition ]; then
+        readlink -f "${1}"
+        return $?
+    fi
+    _disk=$(readlink -f "${_syspath}"/..)
+    if [ -n "${_disk}" ]; then
+        printf '/dev/%s\n' "${_disk##*/}"
+        return 0
+    fi
+    return 1
+}
+
 has_fs() {
     dev="$1"
     fstype=$(blkid -o value -s TYPE "${dev}")
     [ -n "${fstype}" ]
 }
 
+last_partition() {
+    cat /sys/class/block/"${1##*/}"/*/partition \
+        | sort -n \
+        | tail -n1
+}
+
+partition_number() {
+    cat /sys/class/block/${1##*/}/partition
+}
+
 relabel_all() {
     selinuxtype=$(. /etc/selinux/config && echo ${SELINUXTYPE})
     find "${tmpdir}" | \
@@ -59,6 +100,29 @@ relabel_all() {
         /etc/selinux/${selinuxtype}/contexts/files/file_contexts
 }
 
+resize_partition() {
+    _disk="${1}"
+    _part="${2}"
+    _lastpart=$(last_partition "${_disk}")
+    if [ "${_part}" -ne "${_lastpart}" ]; then
+        printf 'Cannot resize %s, it is not the last partition on the disk\n' \
+            "${_dev}" \
+            >&2
+        return 1
+    fi
+    _uuid=$(sfdisk --part-uuid "${_disk}" "${_part}") || return $?
+    _type=$(sfdisk --part-type "${_disk}" "${_part}") || return $?
+    _label=$(sfdisk --part-label "${_disk}" "${_part}") || return $?
+    sfdisk --delete "${_disk}" "${_part}" || return $?
+    printf 'type=%s, uuid=%s, name="%s"\n' \
+        "${_type}" \
+        "${_uuid}" \
+        "${_label}" \
+        | sfdisk -N "${_part}" "${_disk}" --force \
+        || return $?
+    partx -u "${_disk}"
+}
+
 setup_etc() {
     dev="$1"