XMLBuilder: Provide default fget and fset impls

This is the first step towards unifying the XML handling split between
parsing and creating from scratch. Demonstrate it with VirtualDisk.iotune
bits.

tests/xmlconfig-xml/boot-many-disks2.xml

@@ -43,11 +43,21 @@
     </disk>
     <disk type="block" device="floppy">
       <target dev="fda" bus="fdc"/>
+      <iotune>
+        <total_bytes_sec>1</total_bytes_sec>
+        <total_iops_sec>2</total_iops_sec>
+      </iotune>
     </disk>
     <disk type="block" device="floppy">
       <driver name="phy" cache="none"/>
       <source dev="/dev/loop0"/>
       <target dev="fdb" bus="fdc"/>
+      <iotune>
+        <read_bytes_sec>5555</read_bytes_sec>
+        <read_iops_sec>1234</read_iops_sec>
+        <write_bytes_sec>3</write_bytes_sec>
+        <write_iops_sec>4</write_iops_sec>
+      </iotune>
     </disk>
     <disk type="block" device="disk">
       <driver name="qemu" type="qcow2" cache="none" io="threads"/>

tests/xmlconfig.py

@@ -550,19 +550,28 @@ class TestXMLConfig(unittest.TestCase):
         g.add_device(VirtualDisk(g.conn, path=None,
                                  device=VirtualDisk.DEVICE_CDROM,
                                  bus="scsi"))
-        g.add_device(VirtualDisk(g.conn, path=None,
-                                 device=VirtualDisk.DEVICE_FLOPPY))
-        d1 = VirtualDisk(g.conn, path="/dev/loop0",
-                         device=VirtualDisk.DEVICE_FLOPPY,
-                         driverName="phy")
-        d1.driver_cache = "none"
-        g.add_device(d1)
-        d2 = VirtualDisk(g.conn, path="/dev/loop0",
-                         bus="virtio", driverName="qemu",
-                         driverType="qcow2")
-        d2.driver_cache = "none"
-        d2.driver_io = "threads"
-        g.add_device(d2)
+        d = VirtualDisk(g.conn, path=None,
+                        device=VirtualDisk.DEVICE_FLOPPY)
+        d.iotune_tbs = 1
+        d.iotune_tis = 2
+        g.add_device(d)
+
+        d = VirtualDisk(g.conn, path="/dev/loop0",
+                        device=VirtualDisk.DEVICE_FLOPPY,
+                        driverName="phy")
+        d.driver_cache = "none"
+        d.iotune_rbs = 5555
+        d.iotune_ris = 1234
+        d.iotune_wbs = 3
+        d.iotune_wis = 4
+        g.add_device(d)
+
+        d = VirtualDisk(g.conn, path="/dev/loop0",
+                        bus="virtio", driverName="qemu",
+                        driverType="qcow2")
+        d.driver_cache = "none"
+        d.driver_io = "threads"
+        g.add_device(d)
 
         self._compare(g, "boot-many-disks2", False)
 

tests/xmlparse-xml/change-disk-in.xml

@@ -45,6 +45,12 @@
     </disk>
     <disk type="block" device="floppy">
       <target dev="fda" bus="fdc"/>
+      <iotune>
+        <read_iops_sec>1</read_iops_sec>
+        <read_bytes_sec>2</read_bytes_sec>
+        <write_iops_sec>3</write_iops_sec>
+        <write_bytes_sec>4</write_bytes_sec>
+      </iotune>
     </disk>
     <disk type="block" device="floppy">
       <driver name="phy" cache="none"/>

tests/xmlparse-xml/change-disk-out.xml

@@ -42,6 +42,10 @@
     </disk>
     <disk type="file" device="floppy">
       <target dev="fda" bus="fdc"/>
+      <iotune>
+        <total_iops_sec>5</total_iops_sec>
+        <total_bytes_sec>6</total_bytes_sec>
+      </iotune>
       <source file="/default-pool/default-vol"/>
       <shareable/>
       <driver cache="writeback" io="native"/>

tests/xmlparse.py

@@ -249,10 +249,10 @@ class XMLParseTest(unittest.TestCase):
         disks = guest.get_devices("disk")
         disk1 = disks[0]
         disk1.size = 1
-        disk2 = disks[2]
-        disk2.size = 1
-        disk3 = disks[5]
+        disk3 = disks[2]
         disk3.size = 1
+        disk6 = disks[5]
+        disk6.size = 1
 
         check = self._make_checker(disk1)
         check("path", "/tmp/test.img", "/dev/loop0")
@@ -260,7 +260,7 @@ class XMLParseTest(unittest.TestCase):
         check("driver_type", None, "raw")
         check("serial", "WD-WMAP9A966149", "frob")
 
-        check = self._make_checker(disk2)
+        check = self._make_checker(disk3)
         check("path", "/dev/loop0", None)
         check("device", "cdrom", "floppy")
         check("read_only", True, False)
@@ -268,12 +268,19 @@ class XMLParseTest(unittest.TestCase):
         check("bus", None, "fdc")
         check("error_policy", "stop", None)
 
-        check = self._make_checker(disk3)
+        check = self._make_checker(disk6)
         check("path", None, "/default-pool/default-vol")
         check("shareable", False, True)
         check("driver_cache", None, "writeback")
         check("driver_io", None, "threads")
         check("driver_io", "threads", "native")
+        check("iotune_ris", 1, 0)
+        check("iotune_rbs", 2, 0)
+        check("iotune_wis", 3, 0)
+        check("iotune_wbs", 4, 0)
+        check("iotune_tis", 0, 5)
+        check("iotune_tbs", 0, 6)
+
 
         self._alter_compare(guest.get_xml_config(), outfile)