Added handler for setting virtio block cache to none. (9ad928d3) · Commits · Mirror / cc-node

cloudcontrol/node/hypervisor/init.py

+41 −0

Original line number	Diff line number	Diff line
		@@ -139,6 +139,8 @@ class Handler(HostHandler):
		self.main.reset_handler('drbd_sync_status', self.drbd_sync_status)
		self.main.reset_handler('drbd_shutdown', self.drbd_shutdown)
		self.main.reset_handler('vm_open_console', self.vm_open_console)
		self.main.reset_handler('vm_disable_virtio_cache',
		self.vm_disable_virtio_cache)

		# if everything went fine, unregister the timer
		self.timer.stop()
		@@ -202,6 +204,7 @@ class Handler(HostHandler):
		self.main.remove_handler('drbd_sync_status')
		self.main.remove_handler('drbd_shutdown')
		self.main.remove_handler('vm_open_console')
		self.main.remove_handler('vm_disable_virtio_cache')
		# launch connection timer
		self.timer.start()

		@@ -470,6 +473,44 @@ class Handler(HostHandler):
		proto = conn.create_tunnel(endpoint=endpoint, on_close=on_close)
		return proto.label

		def vm_disable_virtio_cache(self, name):
		"""Set virtio cache to none on VM disks.

		:param name: VM name
		"""
		vm = self.hypervisor.domains[name]

		# get VM XML
		try:
		xml = vm.lv_dom.XMLDesc(0)
		except libvirt.libvirtError:
		logger.exception('Error while getting domain XML from libvirt, %s',
		vm.name)
		raise

		xml_tree = et.ElementTree()
		xml_tree.parse(StringIO(xml))
		for disk in xml_tree.findall('devices/disk'):
		# check that disk is virtio
		target = disk.find('target')
		if target is None or target.get('bus') != 'virtio':
		continue
		# modify cache attr
		driver = disk.find('driver')
		assert driver is not None
		driver.set('cache', 'none')
		logger.debug('Set cache attribute for disk %s of VM %s',
		target.get('dev'), name)

		# write back the XML tree
		out = StringIO()
		xml_tree.write(out) # check encoding is fine
		try:
		self.hypervisor.vir_con.defineXML(out.getvalue())
		except libvirt.libvirtError:
		logger.exception('Cannot update XML file for domain %s', name)
		raise

		def vol_create(self, pool, name, size):
		logger.debug('Volume create %s, pool %s, size %s', name, pool, size)
		try: