devicedisk: Add set_vol_install

And use it in places where we don't need set_create_storage

virtinst/cli.py

@@ -1585,7 +1585,7 @@ class ParserDisk(VirtCLIParser):
             vol_install = VirtualDisk.build_vol_install(
                     self.guest.conn, newvolname, poolobj, size, sparse,
                     fmt=fmt, backing_store=backing_store)
-            inst.set_create_storage(vol_install=vol_install)
+            inst.set_vol_install(vol_install)
 
         if not inst.target:
             skip_targets = [d.target for d in self.guest.get_devices("disk")]

virtinst/devicedisk.py

@@ -509,6 +509,11 @@ class VirtualDisk(VirtualDevice):
         self._change_backend(None, vol_object)
         self._set_xmlpath(self.path)
 
+    def set_vol_install(self, vol_install):
+        self._storage_creator = diskbackend.StorageCreator(self.conn,
+            None, None, vol_install, None, None, None, None, None)
+        self._set_xmlpath(self.path)
+
     def get_vol_object(self):
         return self._storage_backend.get_vol_object()
     def get_vol_install(self):

virtinst/distroinstaller.py

@@ -106,9 +106,6 @@ def _upload_file(conn, meter, destpool, src):
     # Build placeholder volume
     size = os.path.getsize(src)
     basename = os.path.basename(src)
-    xmlobj = StoragePool(conn, parsexml=destpool.XMLDesc(0))
-    poolpath = xmlobj.target_path
-
     name = StorageVolume.find_free_name(destpool, basename)
     if name != basename:
         logging.debug("Generated non-colliding volume name %s", name)
@@ -117,8 +114,7 @@ def _upload_file(conn, meter, destpool, src):
                     (float(size) / 1024.0 / 1024.0 / 1024.0), True)
 
     disk = VirtualDisk(conn)
-    disk.path = os.path.join(poolpath, name)
-    disk.set_create_storage(vol_install=vol_install)
+    disk.set_vol_install(vol_install)
     disk.validate()
 
     disk.setup(meter=meter)