diff --git a/docs/schemas/nodedev.rng b/docs/schemas/nodedev.rng
index 6b063cc225..0498489cfd 100644
--- a/docs/schemas/nodedev.rng
+++ b/docs/schemas/nodedev.rng
@@ -578,6 +578,7 @@
           <text/>
         </element>
       </optional>
+      <ref name='blockData'/>
     </element>
   </define>
 
@@ -585,6 +586,18 @@
     <element name='size'>
       <ref name='unsignedLong'/>
     </element>
+    <ref name='blockData'/>
+  </define>
+
+  <define name='blockData'>
+    <optional>
+      <element name='logical_block_size'>
+        <ref name='unsignedLong'/>
+      </element>
+      <element name='num_blocks'>
+        <ref name='unsignedLong'/>
+      </element>
+    </optional>
   </define>
 
   <define name='capdrm'>
diff --git a/tests/nodedevschemadata/DVD_with_media.xml b/tests/nodedevschemadata/DVD_with_media.xml
index 673e88fd0a..f169885eb1 100644
--- a/tests/nodedevschemadata/DVD_with_media.xml
+++ b/tests/nodedevschemadata/DVD_with_media.xml
@@ -11,6 +11,8 @@
       <media_available>1</media_available>
       <media_size>12345678</media_size>
       <media_label>Windows_XP_Label</media_label>
+      <logical_block_size>2048</logical_block_size>
+      <num_blocks>6028</num_blocks>
     </capability>
   </capability>
 </device>
diff --git a/tests/nodedevschemadata/storage_serial_3600c0ff000d7a2a5d463ff4902000000.xml b/tests/nodedevschemadata/storage_serial_3600c0ff000d7a2a5d463ff4902000000.xml
index d225dca8fa..5bdbb8ac95 100644
--- a/tests/nodedevschemadata/storage_serial_3600c0ff000d7a2a5d463ff4902000000.xml
+++ b/tests/nodedevschemadata/storage_serial_3600c0ff000d7a2a5d463ff4902000000.xml
@@ -13,5 +13,7 @@
     <vendor>HP</vendor>
     <serial>3600c0ff000d7a2a5d463ff4902000000</serial>
     <size>15626928128</size>
+    <logical_block_size>512</logical_block_size>
+    <num_blocks>30521344</num_blocks>
   </capability>
 </device>
diff --git a/tests/nodedevschemadata/storage_serial_SATA_HTS721010G9SA00_MPCZ12Y0GNGWSE.xml b/tests/nodedevschemadata/storage_serial_SATA_HTS721010G9SA00_MPCZ12Y0GNGWSE.xml
index 3595a0baaa..68dbf0be96 100644
--- a/tests/nodedevschemadata/storage_serial_SATA_HTS721010G9SA00_MPCZ12Y0GNGWSE.xml
+++ b/tests/nodedevschemadata/storage_serial_SATA_HTS721010G9SA00_MPCZ12Y0GNGWSE.xml
@@ -8,5 +8,7 @@
     <model>HTS721010G9SA00</model>
     <vendor>ATA</vendor>
     <size>100030242816</size>
+    <logical_block_size>512</logical_block_size>
+    <num_blocks>195371568</num_blocks>
   </capability>
 </device>
diff --git a/tests/nodedevxml2xmltest.c b/tests/nodedevxml2xmltest.c
index 41ed5c01c2..207d97483e 100644
--- a/tests/nodedevxml2xmltest.c
+++ b/tests/nodedevxml2xmltest.c
@@ -23,6 +23,7 @@ testCompareXMLToXMLFiles(const char *xml)
     char *actual = NULL;
     int ret = -1;
     virNodeDeviceDefPtr dev = NULL;
+    virNodeDevCapsDefPtr caps;
 
     if (virTestLoadFile(xml, &xmlData) < 0)
         goto fail;
@@ -30,6 +31,27 @@ testCompareXMLToXMLFiles(const char *xml)
     if (!(dev = virNodeDeviceDefParseString(xmlData, EXISTING_DEVICE, NULL)))
         goto fail;
 
+    /* Calculate some things that are not read in */
+    for (caps = dev->caps; caps; caps = caps->next) {
+        virNodeDevCapDataPtr data = &caps->data;
+
+        if (caps->data.type == VIR_NODE_DEV_CAP_STORAGE) {
+            if (data->storage.flags & VIR_NODE_DEV_CAP_STORAGE_REMOVABLE) {
+                if (data->storage.flags &
+                    VIR_NODE_DEV_CAP_STORAGE_REMOVABLE_MEDIA_AVAILABLE) {
+                    data->storage.logical_block_size = 2048;
+                    data->storage.num_blocks =
+                        data->storage.removable_media_size /
+                        data->storage.logical_block_size;
+                }
+            } else {
+                data->storage.logical_block_size = 512;
+                data->storage.num_blocks = data->storage.size /
+                                           data->storage.logical_block_size;
+            }
+        }
+    }
+
     if (!(actual = virNodeDeviceDefFormat(dev)))
         goto fail;