diff --git a/nova/privsep/xenapi.py b/nova/privsep/xenapi.py
index 023e16f9cee1..d1e470dff525 100644
--- a/nova/privsep/xenapi.py
+++ b/nova/privsep/xenapi.py
@@ -24,3 +24,14 @@ import nova.privsep
 @nova.privsep.sys_admin_pctxt.entrypoint
 def xenstore_read(path):
     return processutils.execute('xenstore-read', path)
+
+
+@nova.privsep.sys_admin_pctxt.entrypoint
+def block_copy(src_path, dst_path, block_size, num_blocks):
+    processutils.execute('dd',
+                         'if=%s' % src_path,
+                         'of=%s' % dst_path,
+                         'bs=%d' % block_size,
+                         'count=%d' % num_blocks,
+                         'iflag=direct,sync',
+                         'oflag=direct,sync')
diff --git a/nova/virt/xenapi/vm_utils.py b/nova/virt/xenapi/vm_utils.py
index 71fe41aee67f..dcf680899cf2 100644
--- a/nova/virt/xenapi/vm_utils.py
+++ b/nova/virt/xenapi/vm_utils.py
@@ -2399,14 +2399,8 @@ def _copy_partition(session, src_ref, dst_ref, partition, virtual_size):
                 _sparse_copy(src_path, dst_path, virtual_size)
             else:
                 num_blocks = virtual_size / SECTOR_SIZE
-                utils.execute('dd',
-                              'if=%s' % src_path,
-                              'of=%s' % dst_path,
-                              'bs=%d' % DD_BLOCKSIZE,
-                              'count=%d' % num_blocks,
-                              'iflag=direct,sync',
-                              'oflag=direct,sync',
-                              run_as_root=True)
+                nova.privsep.xenapi.block_copy(
+                    src_path, dst_path, DD_BLOCKSIZE, num_blocks)
 
 
 def _mount_filesystem(dev_path, mount_point):