merge trunk

7 files changed, 480 insertions, 76 deletions

diff --git a/nova/virt/connection.py b/nova/virt/connection.py
index 13181b730..af7001715 100644
--- a/nova/virt/connection.py
+++ b/nova/virt/connection.py
@@ -23,6 +23,8 @@ import sys
 
 from nova import flags
 from nova import log as logging
+from nova import utils
+from nova.virt import driver
 from nova.virt import fake
 from nova.virt import libvirt_conn
 from nova.virt import xenapi_conn
@@ -72,4 +74,4 @@ def get_connection(read_only=False):
     if conn is None:
         LOG.error(_('Failed to open connection to the hypervisor'))
         sys.exit(1)
-    return conn
+    return utils.check_isinstance(conn, driver.ComputeDriver)
diff --git a/nova/virt/driver.py b/nova/virt/driver.py
new file mode 100644
index 000000000..0e3a4aa3b
--- /dev/null
+++ b/nova/virt/driver.py
@@ -0,0 +1,234 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 Justin Santa Barbara
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Driver base-classes:
+
+    (Beginning of) the contract that compute drivers must follow, and shared
+    types that support that contract
+"""
+
+from nova.compute import power_state
+
+
+class InstanceInfo(object):
+    def __init__(self, name, state):
+        self.name = name
+        assert state in power_state.valid_states(), "Bad state: %s" % state
+        self.state = state
+
+
+class ComputeDriver(object):
+    """Base class for compute drivers.
+
+    Lots of documentation is currently on fake.py.
+    """
+
+    def init_host(self, host):
+        """Adopt existing VM's running here"""
+        raise NotImplementedError()
+
+    def get_info(self, instance_name):
+        """Get the current status of an instance, by name (not ID!)
+
+        Returns a dict containing:
+        :state:           the running state, one of the power_state codes
+        :max_mem:         (int) the maximum memory in KBytes allowed
+        :mem:             (int) the memory in KBytes used by the domain
+        :num_cpu:         (int) the number of virtual CPUs for the domain
+        :cpu_time:        (int) the CPU time used in nanoseconds
+        """
+        raise NotImplementedError()
+
+    def list_instances(self):
+        raise NotImplementedError()
+
+    def list_instances_detail(self):
+        """Return a list of InstanceInfo for all registered VMs"""
+        raise NotImplementedError()
+
+    def spawn(self, instance):
+        """Launch a VM for the specified instance"""
+        raise NotImplementedError()
+
+    def destroy(self, instance, cleanup=True):
+        """Shutdown specified VM"""
+        raise NotImplementedError()
+
+    def reboot(self, instance):
+        """Reboot specified VM"""
+        raise NotImplementedError()
+
+    def snapshot_instance(self, context, instance_id, image_id):
+        raise NotImplementedError()
+
+    def get_console_pool_info(self, console_type):
+        """???
+
+        Returns a dict containing:
+        :address:          ???
+        :username:         ???
+        :password:         ???
+        """
+        raise NotImplementedError()
+
+    def get_console_output(self, instance):
+        raise NotImplementedError()
+
+    def get_ajax_console(self, instance):
+        raise NotImplementedError()
+
+    def get_diagnostics(self, instance):
+        """Return data about VM diagnostics"""
+        raise NotImplementedError()
+
+    def get_host_ip_addr(self):
+        raise NotImplementedError()
+
+    def attach_volume(self, context, instance_id, volume_id, mountpoint):
+        raise NotImplementedError()
+
+    def detach_volume(self, context, instance_id, volume_id):
+        raise NotImplementedError()
+
+    def compare_cpu(self, context, cpu_info):
+        raise NotImplementedError()
+
+    def migrate_disk_and_power_off(self, instance, dest):
+        """Transfers the VHD of a running instance to another host, then shuts
+        off the instance copies over the COW disk"""
+        raise NotImplementedError()
+
+    def snapshot(self, instance, image_id):
+        """ Create snapshot from a running VM instance """
+        raise NotImplementedError()
+
+    def finish_resize(self, instance, disk_info):
+        """Completes a resize, turning on the migrated instance"""
+        raise NotImplementedError()
+
+    def revert_resize(self, instance):
+        """Reverts a resize, powering back on the instance"""
+        raise NotImplementedError()
+
+    def pause(self, instance, callback):
+        """Pause VM instance"""
+        raise NotImplementedError()
+
+    def unpause(self, instance, callback):
+        """Unpause paused VM instance"""
+        raise NotImplementedError()
+
+    def suspend(self, instance, callback):
+        """suspend the specified instance"""
+        raise NotImplementedError()
+
+    def resume(self, instance, callback):
+        """resume the specified instance"""
+        raise NotImplementedError()
+
+    def rescue(self, instance, callback):
+        """Rescue the specified instance"""
+        raise NotImplementedError()
+
+    def unrescue(self, instance, callback):
+        """Unrescue the specified instance"""
+        raise NotImplementedError()
+
+    def update_available_resource(self, ctxt, host):
+        """Updates compute manager resource info on ComputeNode table.
+
+        This method is called when nova-compute launches, and
+        whenever admin executes "nova-manage service update_resource".
+
+        :param ctxt: security context
+        :param host: hostname that compute manager is currently running
+
+        """
+        raise NotImplementedError()
+
+    def live_migration(self, ctxt, instance_ref, dest,
+                       post_method, recover_method):
+        """Spawning live_migration operation for distributing high-load.
+
+        :params ctxt: security context
+        :params instance_ref:
+            nova.db.sqlalchemy.models.Instance object
+            instance object that is migrated.
+        :params dest: destination host
+        :params post_method:
+            post operation method.
+            expected nova.compute.manager.post_live_migration.
+        :params recover_method:
+            recovery method when any exception occurs.
+            expected nova.compute.manager.recover_live_migration.
+
+        """
+        raise NotImplementedError()
+
+    def refresh_security_group_rules(self, security_group_id):
+        raise NotImplementedError()
+
+    def refresh_security_group_members(self, security_group_id):
+        raise NotImplementedError()
+
+    def reset_network(self, instance):
+        """reset networking for specified instance"""
+        raise NotImplementedError()
+
+    def ensure_filtering_rules_for_instance(self, instance_ref):
+        """Setting up filtering rules and waiting for its completion.
+
+        To migrate an instance, filtering rules to hypervisors
+        and firewalls are inevitable on destination host.
+        ( Waiting only for filtering rules to hypervisor,
+        since filtering rules to firewall rules can be set faster).
+
+        Concretely, the below method must be called.
+        - setup_basic_filtering (for nova-basic, etc.)
+        - prepare_instance_filter(for nova-instance-instance-xxx, etc.)
+
+        to_xml may have to be called since it defines PROJNET, PROJMASK.
+        but libvirt migrates those value through migrateToURI(),
+        so , no need to be called.
+
+        Don't use thread for this method since migration should
+        not be started when setting-up filtering rules operations
+        are not completed.
+
+        :params instance_ref: nova.db.sqlalchemy.models.Instance object
+
+        """
+        raise NotImplementedError()
+
+    def unfilter_instance(self, instance):
+        """Stop filtering instance"""
+        raise NotImplementedError()
+
+    def set_admin_password(self, context, instance_id, new_pass=None):
+        """Set the root/admin password for an instance on this server."""
+        raise NotImplementedError()
+
+    def inject_file(self, instance, b64_path, b64_contents):
+        """Create a file on the VM instance. The file path and contents
+        should be base64-encoded.
+        """
+        raise NotImplementedError()
+
+    def inject_network_info(self, instance):
+        """inject network info for specified instance"""
+        raise NotImplementedError()
diff --git a/nova/virt/fake.py b/nova/virt/fake.py
index 3a06284a1..5b0fe1877 100644
--- a/nova/virt/fake.py
+++ b/nova/virt/fake.py
@@ -26,7 +26,9 @@ semantics of real hypervisor connections.
 """
 
 from nova import exception
+from nova import utils
 from nova.compute import power_state
+from nova.virt import driver
 
 
 def get_connection(_):
@@ -34,7 +36,14 @@ def get_connection(_):
     return FakeConnection.instance()
 
 
-class FakeConnection(object):
+class FakeInstance(object):
+
+    def __init__(self, name, state):
+        self.name = name
+        self.state = state
+
+
+class FakeConnection(driver.ComputeDriver):
     """
     The interface to this class talks in terms of 'instances' (Amazon EC2 and
     internal Nova terminology), by which we mean 'running virtual machine'
@@ -90,6 +99,17 @@ class FakeConnection(object):
         """
         return self.instances.keys()
 
+    def _map_to_instance_info(self, instance):
+        instance = utils.check_isinstance(instance, FakeInstance)
+        info = driver.InstanceInfo(instance.name, instance.state)
+        return info
+
+    def list_instances_detail(self):
+        info_list = []
+        for instance in self.instances.values():
+            info_list.append(self._map_to_instance_info(instance))
+        return info_list
+
     def spawn(self, instance):
         """
         Create a new instance/VM/domain on the virtualization platform.
@@ -109,9 +129,10 @@ class FakeConnection(object):
         that it was before this call began.
         """
 
-        fake_instance = FakeInstance()
-        self.instances[instance.name] = fake_instance
-        fake_instance._state = power_state.RUNNING
+        name = instance.name
+        state = power_state.RUNNING
+        fake_instance = FakeInstance(name, state)
+        self.instances[name] = fake_instance
 
     def snapshot(self, instance, name):
         """
@@ -270,7 +291,7 @@ class FakeConnection(object):
             raise exception.NotFound(_("Instance %s Not Found")
                                      % instance_name)
         i = self.instances[instance_name]
-        return {'state': i._state,
+        return {'state': i.state,
                 'max_mem': 0,
                 'mem': 0,
                 'num_cpu': 2,
@@ -428,8 +449,6 @@ class FakeConnection(object):
         """This method is supported only by libvirt."""
         raise NotImplementedError('This method is supported only by libvirt.')
 
-
-class FakeInstance(object):
-
-    def __init__(self):
-        self._state = power_state.NOSTATE
+    def test_remove_vm(self, instance_name):
+        """ Removes the named VM, as if it crashed. For testing"""
+        self.instances.pop(instance_name)
diff --git a/nova/virt/hyperv.py b/nova/virt/hyperv.py
index 29d18dac5..a1ed5ebbf 100644
--- a/nova/virt/hyperv.py
+++ b/nova/virt/hyperv.py
@@ -68,6 +68,7 @@ from nova import flags
 from nova import log as logging
 from nova.auth import manager
 from nova.compute import power_state
+from nova.virt import driver
 from nova.virt import images
 
 wmi = None
@@ -108,8 +109,9 @@ def get_connection(_):
     return HyperVConnection()
 
 
-class HyperVConnection(object):
+class HyperVConnection(driver.ComputeDriver):
     def __init__(self):
+        super(HyperVConnection, self).__init__()
         self._conn = wmi.WMI(moniker='//./root/virtualization')
         self._cim_conn = wmi.WMI(moniker='//./root/cimv2')
 
@@ -124,6 +126,19 @@ class HyperVConnection(object):
                 for v in self._conn.Msvm_ComputerSystem(['ElementName'])]
         return vms
 
+    def list_instances_detail(self):
+        # TODO(justinsb): This is a terrible implementation (1+N)
+        instance_infos = []
+        for instance_name in self.list_instances():
+            info = self.get_info(instance_name)
+
+            state = info['state']
+
+            instance_info = driver.InstanceInfo(instance_name, state)
+            instance_infos.append(instance_info)
+
+        return instance_infos
+
     def spawn(self, instance):
         """ Create a new VM and start it."""
         vm = self._lookup(instance.name)
@@ -345,7 +360,7 @@ class HyperVConnection(object):
         newinst = cl.new()
         #Copy the properties from the original.
         for prop in wmi_obj._properties:
-            newinst.Properties_.Item(prop).Value =\
+            newinst.Properties_.Item(prop).Value = \
                     wmi_obj.Properties_.Item(prop).Value
         return newinst
 
@@ -467,3 +482,6 @@ class HyperVConnection(object):
         if vm is None:
             raise exception.NotFound('Cannot detach volume from missing %s '
                     % instance_name)
+
+    def poll_rescued_instances(self, timeout):
+        pass
diff --git a/nova/virt/libvirt_conn.py b/nova/virt/libvirt_conn.py
index f264cf619..e1a0a6f29 100644
--- a/nova/virt/libvirt_conn.py
+++ b/nova/virt/libvirt_conn.py
@@ -42,13 +42,12 @@ import shutil
 import sys
 import random
 import subprocess
-import time
 import uuid
 from xml.dom import minidom
 
 from eventlet import greenthread
 from eventlet import tpool
-from eventlet import semaphore
+
 import IPy
 
 from nova import context
@@ -62,6 +61,7 @@ from nova.auth import manager
 from nova.compute import instance_types
 from nova.compute import power_state
 from nova.virt import disk
+from nova.virt import driver
 from nova.virt import images
 
 libvirt = None
@@ -133,8 +133,8 @@ def get_connection(read_only):
 def _late_load_cheetah():
     global Template
     if Template is None:
-        t = __import__('Cheetah.Template', globals(), locals(), ['Template'],
-                       -1)
+        t = __import__('Cheetah.Template', globals(), locals(),
+                       ['Template'], -1)
         Template = t.Template
 
 
@@ -153,9 +153,10 @@ def _get_ip_version(cidr):
         return int(net.version())
 
 
-class LibvirtConnection(object):
+class LibvirtConnection(driver.ComputeDriver):
 
     def __init__(self, read_only):
+        super(LibvirtConnection, self).__init__()
         self.libvirt_uri = self.get_uri()
 
         self.libvirt_xml = open(FLAGS.libvirt_xml_template).read()
@@ -235,6 +236,29 @@ class LibvirtConnection(object):
         return [self._conn.lookupByID(x).name()
                 for x in self._conn.listDomainsID()]
 
+    def _map_to_instance_info(self, domain):
+        """Gets info from a virsh domain object into an InstanceInfo"""
+
+        # domain.info() returns a list of:
+        #    state:       one of the state values (virDomainState)
+        #    maxMemory:   the maximum memory used by the domain
+        #    memory:      the current amount of memory used by the domain
+        #    nbVirtCPU:   the number of virtual CPU
+        #    puTime:      the time used by the domain in nanoseconds
+
+        (state, _max_mem, _mem, _num_cpu, _cpu_time) = domain.info()
+        name = domain.name()
+
+        return driver.InstanceInfo(name, state)
+
+    def list_instances_detail(self):
+        infos = []
+        for domain_id in self._conn.listDomainsID():
+            domain = self._conn.lookupByID(domain_id)
+            info = self._map_to_instance_info(domain)
+            infos.append(info)
+        return infos
+
     def destroy(self, instance, cleanup=True):
         try:
             virt_dom = self._conn.lookupByName(instance['name'])
@@ -417,6 +441,10 @@ class LibvirtConnection(object):
         self.reboot(instance)
 
     @exception.wrap_exception
+    def poll_rescued_instances(self, timeout):
+        pass
+
+    @exception.wrap_exception
     def spawn(self, instance):
         xml = self.to_xml(instance)
         db.instance_set_state(context.get_admin_context(),
@@ -556,13 +584,12 @@ class LibvirtConnection(object):
                 os.mkdir(base_dir)
             base = os.path.join(base_dir, fname)
 
-            if fname not in LibvirtConnection._image_sems:
-                LibvirtConnection._image_sems[fname] = semaphore.Semaphore()
-            with LibvirtConnection._image_sems[fname]:
+            @utils.synchronized(fname)
+            def call_if_not_exists(base, fn, *args, **kwargs):
                 if not os.path.exists(base):
                     fn(target=base, *args, **kwargs)
-            if not LibvirtConnection._image_sems[fname].locked():
-                del LibvirtConnection._image_sems[fname]
+
+            call_if_not_exists(base, fn, *args, **kwargs)
 
             if cow:
                 utils.execute('qemu-img', 'create', '-f', 'qcow2', '-o',
@@ -1144,7 +1171,8 @@ class LibvirtConnection(object):
 
         return
 
-    def ensure_filtering_rules_for_instance(self, instance_ref):
+    def ensure_filtering_rules_for_instance(self, instance_ref,
+                                            time=None):
         """Setting up filtering rules and waiting for its completion.
 
         To migrate an instance, filtering rules to hypervisors
@@ -1168,6 +1196,9 @@ class LibvirtConnection(object):
 
         """
 
+        if not time:
+            time = greenthread
+
         # If any instances never launch at destination host,
         # basic-filtering must be set here.
         self.firewall_driver.setup_basic_filtering(instance_ref)
@@ -1780,15 +1811,15 @@ class IptablesFirewallDriver(FirewallDriver):
         pass
 
     def refresh_security_group_rules(self, security_group):
-        # We use the semaphore to make sure noone applies the rule set
-        # after we've yanked the existing rules but before we've put in
-        # the new ones.
-        with self.iptables.semaphore:
-            for instance in self.instances.values():
-                self.remove_filters_for_instance(instance)
-                self.add_filters_for_instance(instance)
+        self.do_refresh_security_group_rules(security_group)
         self.iptables.apply()
 
+    @utils.synchronized('iptables', external=True)
+    def do_refresh_security_group_rules(self, security_group):
+        for instance in self.instances.values():
+            self.remove_filters_for_instance(instance)
+            self.add_filters_for_instance(instance)
+
     def _security_group_chain_name(self, security_group_id):
         return 'nova-sg-%s' % (security_group_id,)
 
diff --git a/nova/virt/xenapi/vmops.py b/nova/virt/xenapi/vmops.py
index df6d3747f..c2c173b6f 100644
--- a/nova/virt/xenapi/vmops.py
+++ b/nova/virt/xenapi/vmops.py
@@ -37,6 +37,7 @@ from nova import utils
 
 from nova.auth.manager import AuthManager
 from nova.compute import power_state
+from nova.virt import driver
 from nova.virt.xenapi.network_utils import NetworkHelper
 from nova.virt.xenapi.vm_utils import VMHelper
 from nova.virt.xenapi.vm_utils import ImageType
@@ -52,11 +53,14 @@ class VMOps(object):
     def __init__(self, session):
         self.XenAPI = session.get_imported_xenapi()
         self._session = session
+        self.poll_rescue_last_ran = None
 
         VMHelper.XenAPI = self.XenAPI
 
     def list_instances(self):
         """List VM instances"""
+        # TODO(justinsb): Should we just always use the details method?
+        #  Seems to be the same number of API calls..
         vm_refs = []
         for vm_ref in self._session.get_xenapi().VM.get_all():
             vm_rec = self._session.get_xenapi().VM.get_record(vm_ref)
@@ -64,6 +68,33 @@ class VMOps(object):
                 vm_refs.append(vm_rec["name_label"])
         return vm_refs
 
+    def list_instances_detail(self):
+        """List VM instances, returning InstanceInfo objects"""
+        instance_infos = []
+        for vm_ref in self._session.get_xenapi().VM.get_all():
+            vm_rec = self._session.get_xenapi().VM.get_record(vm_ref)
+            if not vm_rec["is_a_template"] and not vm_rec["is_control_domain"]:
+                name = vm_rec["name_label"]
+
+                # TODO(justinsb): This a roundabout way to map the state
+                openstack_format = VMHelper.compile_info(vm_rec)
+                state = openstack_format['state']
+
+                instance_info = driver.InstanceInfo(name, state)
+                instance_infos.append(instance_info)
+        return instance_infos
+
+    def revert_resize(self, instance):
+        vm_ref = VMHelper.lookup(self._session, instance.name)
+        self._start(instance, vm_ref)
+
+    def finish_resize(self, instance, disk_info):
+        vdi_uuid = self.link_disks(instance, disk_info['base_copy'],
+                disk_info['cow'])
+        vm_ref = self._create_vm(instance, vdi_uuid)
+        self.resize_instance(instance, vdi_uuid)
+        self._spawn(instance, vm_ref)
+
     def _start(self, instance, vm_ref=None):
         """Power on a VM instance"""
         if not vm_ref:
@@ -74,7 +105,7 @@ class VMOps(object):
         LOG.debug(_("Starting instance %s"), instance.name)
         self._session.call_xenapi('VM.start', vm_ref, False, False)
 
-    def create_disk(self, instance):
+    def _create_disk(self, instance):
         user = AuthManager().get_user(instance.user_id)
         project = AuthManager().get_project(instance.project_id)
         disk_image_type = VMHelper.determine_disk_image_type(instance)
@@ -86,8 +117,9 @@ class VMOps(object):
     def spawn(self, instance, network_info=None):
         try:
             vdi_uuid = disk_image_type = None
-            (vdi_uuid, disk_image_type) = self.create_disk(instance)
-            self._spawn_with_disk(instance, vdi_uuid, network_info)
+            (vdi_uuid, disk_image_type) = self._create_disk(instance)
+            vm_ref = self._create_vm(instance, vdi_uuid, network_info)
+            self._spawn(instance, vm_ref)
         except (self.XenAPI.Failure, OSError, IOError) as spawn_error:
 
             LOG.exception(_("instance %s: Failed to spawn"),
@@ -98,7 +130,7 @@ class VMOps(object):
             #re-throw the error
             raise spawn_error
 
-    def _spawn_with_disk(self, instance, vdi_uuid, network_info=None):
+    def _create_vm(self, instance, vdi_uuid, network_info=None):
         """Create VM instance"""
         instance_name = instance.name
         vm_ref = VMHelper.lookup(self._session, instance_name)
@@ -164,16 +196,19 @@ class VMOps(object):
         VMHelper.create_vbd(session=self._session, vm_ref=vm_ref,
                 vdi_ref=vdi_ref, userdevice=0, bootable=True)
 
-        # inject_network_info and create vifs
         # TODO(tr3buchet) - check to make sure we have network info, otherwise
         # create it now. This goes away once nova-multi-nic hits.
         if network_info is None:
             network_info = self._get_network_info(instance)
         self.create_vifs(vm_ref, network_info)
         self.inject_network_info(instance, vm_ref, network_info)
+        return vm_ref
 
+    def _spawn(self, instance, vm_ref):
+        """Spawn a new instance"""
         LOG.debug(_('Starting VM %s...'), vm_ref)
         self._start(instance, vm_ref)
+        instance_name = instance.name
         LOG.info(_('Spawning VM %(instance_name)s created %(vm_ref)s.')
                  % locals())
 
@@ -380,7 +415,7 @@ class VMOps(object):
         try:
             # transfer the base copy
             template_vm_ref, template_vdi_uuids = self._get_snapshot(instance)
-            base_copy_uuid = template_vdi_uuids[1]
+            base_copy_uuid = template_vdi_uuids['image']
             vdi_ref, vm_vdi_rec = \
                     VMHelper.get_vdi_for_vm_safely(self._session, vm_ref)
             cow_uuid = vm_vdi_rec['uuid']
@@ -395,7 +430,7 @@ class VMOps(object):
             self._session.wait_for_task(task, instance.id)
 
             # Now power down the instance and transfer the COW VHD
-            self._shutdown(instance, vm_ref, method='clean')
+            self._shutdown(instance, vm_ref, hard=False)
 
             params = {'host': dest,
                       'vdi_uuid': cow_uuid,
@@ -415,7 +450,7 @@ class VMOps(object):
         # sensible so we don't need to blindly pass around dictionaries
         return {'base_copy': base_copy_uuid, 'cow': cow_uuid}
 
-    def attach_disk(self, instance, base_copy_uuid, cow_uuid):
+    def link_disks(self, instance, base_copy_uuid, cow_uuid):
         """Links the base copy VHD to the COW via the XAPI plugin"""
         vm_ref = VMHelper.lookup(self._session, instance.name)
         new_base_copy_uuid = str(uuid.uuid4())
@@ -436,9 +471,19 @@ class VMOps(object):
 
         return new_cow_uuid
 
-    def resize(self, instance, flavor):
+    def resize_instance(self, instance, vdi_uuid):
         """Resize a running instance by changing it's RAM and disk size """
-        raise NotImplementedError()
+        #TODO(mdietz): this will need to be adjusted for swap later
+        #The new disk size must be in bytes
+
+        new_disk_size = str(instance.local_gb * 1024 * 1024 * 1024)
+        instance_name = instance.name
+        instance_local_gb = instance.local_gb
+        LOG.debug(_("Resizing VDI %(vdi_uuid)s for instance %(instance_name)s."
+                " Expanding to %(instance_local_gb)d GB") % locals())
+        vdi_ref = self._session.call_xenapi('VDI.get_by_uuid', vdi_uuid)
+        self._session.call_xenapi('VDI.resize_online', vdi_ref, new_disk_size)
+        LOG.debug(_("Resize instance %s complete") % (instance.name))
 
     def reboot(self, instance):
         """Reboot VM instance"""
@@ -513,8 +558,9 @@ class VMOps(object):
         """Shutdown an instance"""
         state = self.get_info(instance['name'])['state']
         if state == power_state.SHUTDOWN:
-            LOG.warn(_("VM %(vm)s already halted, skipping shutdown...") %
-                     locals())
+            instance_name = instance.name
+            LOG.warn(_("VM %(instance_name)s already halted,"
+                    "skipping shutdown...") % locals())
             return
 
         instance_id = instance.id
@@ -532,6 +578,10 @@ class VMOps(object):
         except self.XenAPI.Failure, exc:
             LOG.exception(exc)
 
+    def _shutdown_rescue(self, rescue_vm_ref):
+        """Shutdown a rescue instance"""
+        self._session.call_xenapi("Async.VM.hard_shutdown", rescue_vm_ref)
+
     def _destroy_vdis(self, instance, vm_ref):
         """Destroys all VDIs associated with a VM"""
         instance_id = instance.id
@@ -549,6 +599,24 @@ class VMOps(object):
             except self.XenAPI.Failure, exc:
                 LOG.exception(exc)
 
+    def _destroy_rescue_vdis(self, rescue_vm_ref):
+        """Destroys all VDIs associated with a rescued VM"""
+        vdi_refs = VMHelper.lookup_vm_vdis(self._session, rescue_vm_ref)
+        for vdi_ref in vdi_refs:
+            try:
+                self._session.call_xenapi("Async.VDI.destroy", vdi_ref)
+            except self.XenAPI.Failure:
+                continue
+
+    def _destroy_rescue_vbds(self, rescue_vm_ref):
+        """Destroys all VBDs tied to a rescue VM"""
+        vbd_refs = self._session.get_xenapi().VM.get_VBDs(rescue_vm_ref)
+        for vbd_ref in vbd_refs:
+            vbd_rec = self._session.get_xenapi().VBD.get_record(vbd_ref)
+            if vbd_rec["userdevice"] == "1":  # primary VBD is always 1
+                VMHelper.unplug_vbd(self._session, vbd_ref)
+                VMHelper.destroy_vbd(self._session, vbd_ref)
+
     def _destroy_kernel_ramdisk_plugin_call(self, kernel, ramdisk):
         args = {}
         if kernel:
@@ -603,6 +671,14 @@ class VMOps(object):
 
         LOG.debug(_("Instance %(instance_id)s VM destroyed") % locals())
 
+    def _destroy_rescue_instance(self, rescue_vm_ref):
+        """Destroy a rescue instance"""
+        self._destroy_rescue_vbds(rescue_vm_ref)
+        self._shutdown_rescue(rescue_vm_ref)
+        self._destroy_rescue_vdis(rescue_vm_ref)
+
+        self._session.call_xenapi("Async.VM.destroy", rescue_vm_ref)
+
     def destroy(self, instance):
         """
         Destroy VM instance
@@ -706,40 +782,56 @@ class VMOps(object):
 
         """
         rescue_vm_ref = VMHelper.lookup(self._session,
-                                    instance.name + "-rescue")
+                                        instance.name + "-rescue")
 
         if not rescue_vm_ref:
             raise exception.NotFound(_(
                 "Instance is not in Rescue Mode: %s" % instance.name))
 
         original_vm_ref = self._get_vm_opaque_ref(instance)
-        vbd_refs = self._session.get_xenapi().VM.get_VBDs(rescue_vm_ref)
-
         instance._rescue = False
 
-        for vbd_ref in vbd_refs:
-            _vbd_ref = self._session.get_xenapi().VBD.get_record(vbd_ref)
-            if _vbd_ref["userdevice"] == "1":
-                VMHelper.unplug_vbd(self._session, vbd_ref)
-                VMHelper.destroy_vbd(self._session, vbd_ref)
+        self._destroy_rescue_instance(rescue_vm_ref)
+        self._release_bootlock(original_vm_ref)
+        self._start(instance, original_vm_ref)
+
+    def poll_rescued_instances(self, timeout):
+        """Look for expirable rescued instances
+            - forcibly exit rescue mode for any instances that have been
+              in rescue mode for >= the provided timeout
+        """
+        last_ran = self.poll_rescue_last_ran
+        if last_ran:
+            if not utils.is_older_than(last_ran, timeout):
+                # Do not run. Let's bail.
+                return
+            else:
+                # Update the time tracker and proceed.
+                self.poll_rescue_last_ran = utils.utcnow()
+        else:
+            # We need a base time to start tracking.
+            self.poll_rescue_last_ran = utils.utcnow()
+            return
 
-        task1 = self._session.call_xenapi("Async.VM.hard_shutdown",
-                                          rescue_vm_ref)
-        self._session.wait_for_task(task1, instance.id)
+        rescue_vms = []
+        for instance in self.list_instances():
+            if instance.endswith("-rescue"):
+                rescue_vms.append(dict(name=instance,
+                                  vm_ref=VMHelper.lookup(self._session,
+                                                         instance)))
 
-        vdi_refs = VMHelper.lookup_vm_vdis(self._session, rescue_vm_ref)
-        for vdi_ref in vdi_refs:
-            try:
-                task = self._session.call_xenapi('Async.VDI.destroy', vdi_ref)
-                self._session.wait_for_task(task, instance.id)
-            except self.XenAPI.Failure:
-                continue
+        for vm in rescue_vms:
+            rescue_name = vm["name"]
+            rescue_vm_ref = vm["vm_ref"]
 
-        task2 = self._session.call_xenapi('Async.VM.destroy', rescue_vm_ref)
-        self._session.wait_for_task(task2, instance.id)
+            self._destroy_rescue_instance(rescue_vm_ref)
 
-        self._release_bootlock(original_vm_ref)
-        self._start(instance, original_vm_ref)
+            original_name = vm["name"].split("-rescue", 1)[0]
+            original_vm_ref = VMHelper.lookup(self._session, original_name)
+
+            self._release_bootlock(original_vm_ref)
+            self._session.call_xenapi("VM.start", original_vm_ref, False,
+                                      False)
 
     def get_info(self, instance):
         """Return data about VM instance"""
@@ -797,8 +889,9 @@ class VMOps(object):
                 'mac': instance.mac_address,
                 'rxtx_cap': flavor['rxtx_cap'],
                 'dns': [network['dns']],
-                'ips': [ip_dict(ip) for ip in network_IPs],
-                'ip6s': [ip6_dict(ip) for ip in network_IPs]}
+                'ips': [ip_dict(ip) for ip in network_IPs]}
+            if network['cidr_v6']:
+                info['ip6s'] = [ip6_dict(ip) for ip in network_IPs]
             network_info.append((network, info))
         return network_info
 
@@ -989,7 +1082,7 @@ class VMOps(object):
         """
         vm_ref = self._get_vm_opaque_ref(instance_or_vm)
         data = self._session.call_xenapi_request('VM.get_xenstore_data',
-                (vm_ref, ))
+                (vm_ref,))
         ret = {}
         if keys is None:
             keys = data.keys()
diff --git a/nova/virt/xenapi_conn.py b/nova/virt/xenapi_conn.py
index 58640fba5..c7e94c508 100644
--- a/nova/virt/xenapi_conn.py
+++ b/nova/virt/xenapi_conn.py
@@ -69,6 +69,7 @@ from nova import db
 from nova import utils
 from nova import flags
 from nova import log as logging
+from nova.virt import driver
 from nova.virt.xenapi.vmops import VMOps
 from nova.virt.xenapi.volumeops import VolumeOps
 
@@ -141,10 +142,11 @@ def get_connection(_):
     return XenAPIConnection(url, username, password)
 
 
-class XenAPIConnection(object):
+class XenAPIConnection(driver.ComputeDriver):
     """A connection to XenServer or Xen Cloud Platform"""
 
     def __init__(self, url, user, pw):
+        super(XenAPIConnection, self).__init__()
         session = XenAPISession(url, user, pw)
         self._vmops = VMOps(session)
         self._volumeops = VolumeOps(session)
@@ -160,24 +162,25 @@ class XenAPIConnection(object):
         """List VM instances"""
         return self._vmops.list_instances()
 
+    def list_instances_detail(self):
+        return self._vmops.list_instances_detail()
+
     def spawn(self, instance):
         """Create VM instance"""
         self._vmops.spawn(instance)
 
+    def revert_resize(self, instance):
+        """Reverts a resize, powering back on the instance"""
+        self._vmops.revert_resize(instance)
+
     def finish_resize(self, instance, disk_info):
         """Completes a resize, turning on the migrated instance"""
-        vdi_uuid = self._vmops.attach_disk(instance, disk_info['base_copy'],
-                disk_info['cow'])
-        self._vmops._spawn_with_disk(instance, vdi_uuid)
+        self._vmops.finish_resize(instance, disk_info)
 
     def snapshot(self, instance, image_id):
         """ Create snapshot from a running VM instance """
         self._vmops.snapshot(instance, image_id)
 
-    def resize(self, instance, flavor):
-        """Resize a VM instance"""
-        raise NotImplementedError()
-
     def reboot(self, instance):
         """Reboot VM instance"""
         self._vmops.reboot(instance)
@@ -225,6 +228,10 @@ class XenAPIConnection(object):
         """Unrescue the specified instance"""
         self._vmops.unrescue(instance, callback)
 
+    def poll_rescued_instances(self, timeout):
+        """Poll for rescued instances"""
+        self._vmops.poll_rescued_instances(timeout)
+
     def reset_network(self, instance):
         """reset networking for specified instance"""
         self._vmops.reset_network(instance)