xenapi: pull vm_mode and auto_disk_config from image when rescue.

Updating vmops.py to pull vm_mode and auto_disk_config from the image
during rescue mode to ensure the vm is properly built based on the image
properties in the image_meta dictionary.

Change-Id: I29c89e9a17f9a170dbe61e4fe14672d481c4fb78
Closes-Bug: 1432913

3 files changed, 51 insertions, 21 deletions

diff --git a/nova/tests/unit/virt/xenapi/test_vmops.py b/nova/tests/unit/virt/xenapi/test_vmops.py
index 172881b17c..64578399a8 100644
--- a/nova/tests/unit/virt/xenapi/test_vmops.py
+++ b/nova/tests/unit/virt/xenapi/test_vmops.py
@@ -331,12 +331,13 @@ class SpawnTestCase(VMOpsTestBase):
         self.vmops._ensure_enough_free_mem(instance)
         self.vmops._create_vm_record(context, instance, name_label,
                 di_type, kernel_file,
-                ramdisk_file, image_meta).AndReturn(vm_ref)
+                ramdisk_file, image_meta, rescue).AndReturn(vm_ref)
         step += 1
         self.vmops._update_instance_progress(context, instance, step, steps)
 
-        self.vmops._attach_disks(instance, vm_ref, name_label, vdis, di_type,
-                          network_info, rescue, admin_password, injected_files)
+        self.vmops._attach_disks(instance, image_meta, vm_ref, name_label,
+                            vdis, di_type, network_info, rescue,
+                            admin_password, injected_files)
         if attach_pci_dev:
             fake_dev = {
                 'created_at': None,
@@ -477,14 +478,15 @@ class SpawnTestCase(VMOpsTestBase):
                 instance, name_label).AndReturn((kernel_file, ramdisk_file))
 
         vm_ref = "fake_vm_ref"
+        rescue = False
         self.vmops._create_vm_record(context, instance, name_label,
                 di_type, kernel_file,
-                ramdisk_file, image_meta).AndReturn(vm_ref)
+                ramdisk_file, image_meta, rescue).AndReturn(vm_ref)
 
         if resize_instance:
             self.vmops._resize_up_vdis(instance, vdis)
-        self.vmops._attach_disks(instance, vm_ref, name_label, vdis, di_type,
-                                 network_info, False, None, None)
+        self.vmops._attach_disks(instance, image_meta, vm_ref, name_label,
+                            vdis, di_type, network_info, False, None, None)
         self.vmops._attach_mapped_block_devices(instance, block_device_info)
         pci_manager.get_instance_pci_devs(instance).AndReturn([])
 
@@ -953,13 +955,14 @@ class CreateVMRecordTestCase(VMOpsTestBase):
         device_id = "0002"
         image_properties = {"xenapi_device_id": device_id}
         image_meta = {"properties": image_properties}
+        rescue = False
         session = "session"
         self.vmops._session = session
         mock_get_vm_device_id.return_value = device_id
         mock_determine_vm_mode.return_value = "vm_mode"
 
         self.vmops._create_vm_record(context, instance, name_label,
-            disk_image_type, kernel_file, ramdisk_file, image_meta)
+            disk_image_type, kernel_file, ramdisk_file, image_meta, rescue)
 
         mock_get_vm_device_id.assert_called_with(session, image_properties)
         mock_create_vm.assert_called_with(session, instance, name_label,
diff --git a/nova/tests/unit/virt/xenapi/test_xenapi.py b/nova/tests/unit/virt/xenapi/test_xenapi.py
index 6d0fd5ccbf..5a86156411 100644
--- a/nova/tests/unit/virt/xenapi/test_xenapi.py
+++ b/nova/tests/unit/virt/xenapi/test_xenapi.py
@@ -1279,7 +1279,8 @@ iface eth0 inet6 static
 
         conn = xenapi_conn.XenAPIDriver(fake.FakeVirtAPI(), False)
         image_meta = {'id': IMAGE_VHD,
-                      'disk_format': 'vhd'}
+                      'disk_format': 'vhd',
+                      'properties': {'vm_mode': 'xen'}}
         conn.rescue(self.context, instance, [], image_meta, '')
 
         vm = xenapi_fake.get_record('VM', vm_ref)
@@ -1304,8 +1305,8 @@ iface eth0 inet6 static
         instance = self._create_instance(obj=True)
         session = get_session()
         image_meta = {'id': IMAGE_VHD,
-                      'disk_format': 'vhd'}
-
+                      'disk_format': 'vhd',
+                      'properties': {'vm_mode': 'xen'}}
         vm_ref = vm_utils.lookup(session, instance['name'])
         vdi_ref, vdi_rec = vm_utils.get_vdi_for_vm_safely(session, vm_ref)
 
@@ -2316,9 +2317,11 @@ class XenAPIAutoDiskConfigTestCase(stubs.XenAPITestBase):
 
         vdi_uuid = session.call_xenapi('VDI.get_record', vdi_ref)['uuid']
         vdis = {'root': {'uuid': vdi_uuid, 'ref': vdi_ref}}
-
-        self.conn._vmops._attach_disks(instance, vm_ref, instance['name'],
-                                       vdis, disk_image_type, "fake_nw_inf")
+        image_meta = {'id': 'null',
+                      'disk_format': 'vhd',
+                      'properties': {'vm_mode': 'xen'}}
+        self.conn._vmops._attach_disks(instance, image_meta, vm_ref,
+                instance['name'], vdis, disk_image_type, "fake_nw_inf")
 
         self.assertEqual(marker["partition_called"], called)
 
@@ -2433,10 +2436,12 @@ class XenAPIGenerateLocal(stubs.XenAPITestBase):
         if disk_image_type == vm_utils.ImageType.DISK_ISO:
             vdi_key = 'iso'
         vdis = {vdi_key: {'uuid': vdi_uuid, 'ref': vdi_ref}}
-
         self.called = False
-        self.conn._vmops._attach_disks(instance, vm_ref, instance['name'],
-                                       vdis, disk_image_type, "fake_nw_inf")
+        image_meta = {'id': 'null',
+                      'disk_format': 'vhd',
+                      'properties': {'vm_mode': 'xen'}}
+        self.conn._vmops._attach_disks(instance, image_meta, vm_ref,
+                    instance['name'], vdis, disk_image_type, "fake_nw_inf")
         self.assertTrue(self.called)
 
     def test_generate_swap(self):
diff --git a/nova/virt/xenapi/vmops.py b/nova/virt/xenapi/vmops.py
index bb8c1fe33d..85582c21cf 100644
--- a/nova/virt/xenapi/vmops.py
+++ b/nova/virt/xenapi/vmops.py
@@ -457,7 +457,7 @@ class VMOps(object):
             if resize:
                 self._resize_up_vdis(instance, vdis)
 
-            self._attach_disks(instance, vm_ref, name_label, vdis,
+            self._attach_disks(instance, image_meta, vm_ref, name_label, vdis,
                                disk_image_type, network_info, rescue,
                                admin_password, injected_files)
             if not first_boot:
@@ -502,7 +502,7 @@ class VMOps(object):
                                   kernel_file, ramdisk_file):
             vm_ref = self._create_vm_record(context, instance, name_label,
                                             disk_image_type, kernel_file,
-                                            ramdisk_file, image_meta)
+                                            ramdisk_file, image_meta, rescue)
 
             def undo_create_vm():
                 self._destroy(instance, vm_ref, network_info=network_info)
@@ -643,7 +643,7 @@ class VMOps(object):
             raise exception.InsufficientFreeMemory(uuid=instance['uuid'])
 
     def _create_vm_record(self, context, instance, name_label, disk_image_type,
-                          kernel_file, ramdisk_file, image_meta):
+                          kernel_file, ramdisk_file, image_meta, rescue=False):
         """Create the VM record in Xen, making sure that we do not create
         a duplicate name-label.  Also do a rough sanity check on memory
         to try to short-circuit a potential failure later.  (The memory
@@ -651,6 +651,15 @@ class VMOps(object):
         that are in progress.)
         """
         mode = vm_utils.determine_vm_mode(instance, disk_image_type)
+        # NOTE(tpownall): If rescue mode then we should try to pull the vm_mode
+        # value from the image properties to ensure the vm is built properly.
+        if rescue:
+            rescue_vm_mode = image_meta['properties'].get('vm_mode', None)
+            if rescue_vm_mode is None:
+                LOG.debug("Failed to pull vm_mode from rescue_image_ref.")
+            else:
+                mode = vm_mode.canonicalize(rescue_vm_mode)
+
         if instance.vm_mode != mode:
             # Update database with normalized (or determined) value
             instance.vm_mode = mode
@@ -665,7 +674,7 @@ class VMOps(object):
                                     use_pv_kernel, device_id)
         return vm_ref
 
-    def _attach_disks(self, instance, vm_ref, name_label, vdis,
+    def _attach_disks(self, instance, image_meta, vm_ref, name_label, vdis,
                       disk_image_type, network_info, rescue=False,
                       admin_password=None, files=None):
         flavor = instance.get_flavor()
@@ -684,7 +693,20 @@ class VMOps(object):
         else:
             root_vdi = vdis['root']
 
-            if instance['auto_disk_config']:
+            auto_disk_config = instance['auto_disk_config']
+            # NOTE(tpownall): If rescue mode we need to ensure that we're
+            # pulling the auto_disk_config value from the image properties so
+            # that we can pull it from the rescue_image_ref.
+            if rescue:
+                rescue_auto_disk_config = image_meta['properties'].get(
+                                                'auto_disk_config', None)
+                if rescue_auto_disk_config is None:
+                    LOG.debug("Failed to pull auto_disk_config value from"
+                              "image.")
+                else:
+                    auto_disk_config = rescue_auto_disk_config
+
+            if auto_disk_config:
                 LOG.debug("Auto configuring disk, attempting to "
                           "resize root disk...", instance=instance)
                 vm_utils.try_auto_configure_disk(self._session,