diff --git a/src/storage/storage_backend_disk.c b/src/storage/storage_backend_disk.c
index 4dc63d753e1e06ed6b305cad2466ac1f1d72f144..c4bd6fe2c501d089b75322c3e1f927d473f7512c 100644
--- a/src/storage/storage_backend_disk.c
+++ b/src/storage/storage_backend_disk.c
@@ -309,7 +309,12 @@ virStorageBackendDiskReadPartitions(virStoragePoolObjPtr pool,
                                pool->def->source.devices[0].path,
                                NULL);
 
-    pool->def->allocation = pool->def->capacity = pool->def->available = 0;
+    /* If a volume is passed, virStorageBackendDiskMakeVol only updates the
+     * pool allocation for that single volume.
+     */
+    if (!vol)
+        pool->def->allocation = 0;
+    pool->def->capacity = pool->def->available = 0;
 
     ret = virCommandRunNul(cmd,
                            6,