diff --git a/functions b/functions
index ca8ef80..cd9e078 100644
--- a/functions
+++ b/functions
@@ -546,6 +546,40 @@
     }
 fi
 
+
+# create_disk - Create backing disk
+function create_disk {
+    local node_number
+    local disk_image=${1}
+    local storage_data_dir=${2}
+    local loopback_disk_size=${3}
+
+    # Create a loopback disk and format it to XFS.
+    if [[ -e ${disk_image} ]]; then
+        if egrep -q ${storage_data_dir} /proc/mounts; then
+            sudo umount ${storage_data_dir}/drives/sdb1
+            sudo rm -f ${disk_image}
+        fi
+    fi
+
+    sudo mkdir -p ${storage_data_dir}/drives/images
+
+    sudo truncate -s ${loopback_disk_size} ${disk_image}
+
+    # Make a fresh XFS filesystem. Use bigger inodes so xattr can fit in
+    # a single inode. Keeping the default inode size (256) will result in multiple
+    # inodes being used to store xattr. Retrieving the xattr will be slower
+    # since we have to read multiple inodes. This statement is true for both
+    # Swift and Ceph.
+    sudo mkfs.xfs -f -i size=1024 ${disk_image}
+
+    # Mount the disk with mount options to make it as efficient as possible
+    if ! egrep -q ${storage_data_dir} /proc/mounts; then
+        sudo mount -t xfs -o loop,noatime,nodiratime,nobarrier,logbufs=8  \
+            ${disk_image} ${storage_data_dir}
+    fi
+}
+
 # Restore xtrace
 $XTRACE