The Xen driver supports running instances in PV or HVM modes, but the method it uses to determine which to use is complicated and doesn't work in all cases. The result is that images that need to use HVM mode (such as FreeBSD 64-bit) end up setting a property named 'os' set to 'windows'.

This branch adds checks for a new property called 'vm_mode'. This can be set to 'pv' or 'hvm' and select the appropriate mode. If the property doesn't exist, the existing logic is still used to determine which mode to use.

4 files changed, 69 insertions, 4 deletions

diff --git a/nova/compute/api.py b/nova/compute/api.py
index 55de5cbce..e2c4cf8d7 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -165,6 +165,9 @@ class API(base.Base):
         os_type = None
         if 'properties' in image and 'os_type' in image['properties']:
             os_type = image['properties']['os_type']
+        vm_mode = None
+        if 'properties' in image and 'vm_mode' in image['properties']:
+            vm_mode = image['properties']['vm_mode']
 
         if kernel_id is None:
             kernel_id = image['properties'].get('kernel_id', None)
@@ -226,7 +229,8 @@ class API(base.Base):
             'locked': False,
             'metadata': metadata,
             'availability_zone': availability_zone,
-            'os_type': os_type}
+            'os_type': os_type,
+            'vm_mode': vm_mode}
 
         return (num_instances, base_options, security_groups)
 
diff --git a/nova/db/sqlalchemy/migrate_repo/versions/023_add_vm_mode_to_instances.py b/nova/db/sqlalchemy/migrate_repo/versions/023_add_vm_mode_to_instances.py
new file mode 100644
index 000000000..0c587f569
--- /dev/null
+++ b/nova/db/sqlalchemy/migrate_repo/versions/023_add_vm_mode_to_instances.py
@@ -0,0 +1,45 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack LLC.
+#
+#    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.
+
+from sqlalchemy import Column, Integer, MetaData, String, Table
+
+meta = MetaData()
+
+instances_vm_mode = Column('vm_mode',
+                           String(length=255, convert_unicode=False,
+                                  assert_unicode=None, unicode_error=None,
+                                  _warn_on_bytestring=False),
+                           nullable=True)
+
+
+def upgrade(migrate_engine):
+    # Upgrade operations go here. Don't create your own engine;
+    # bind migrate_engine to your metadata
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True,
+                      autoload_with=migrate_engine)
+
+    instances.create_column(instances_vm_mode)
+
+
+def downgrade(migrate_engine):
+    meta.bind = migrate_engine
+
+    instances = Table('instances', meta, autoload=True,
+                      autoload_with=migrate_engine)
+
+    instances.drop_column('vm_mode')
diff --git a/nova/db/sqlalchemy/models.py b/nova/db/sqlalchemy/models.py
index 239f6e96a..612ccc93f 100644
--- a/nova/db/sqlalchemy/models.py
+++ b/nova/db/sqlalchemy/models.py
@@ -232,6 +232,7 @@ class Instance(BASE, NovaBase):
     locked = Column(Boolean)
 
     os_type = Column(String(255))
+    vm_mode = Column(String(255))
 
     # TODO(vish): see Ewan's email about state improvements, probably
     #             should be in a driver base class or some such
diff --git a/nova/virt/xenapi/vmops.py b/nova/virt/xenapi/vmops.py
index c6d2b0936..d105cf300 100644
--- a/nova/virt/xenapi/vmops.py
+++ b/nova/virt/xenapi/vmops.py
@@ -160,9 +160,24 @@ class VMOps(object):
         # Create the VM ref and attach the first disk
         first_vdi_ref = self._session.call_xenapi('VDI.get_by_uuid',
                 vdis[0]['vdi_uuid'])
-        use_pv_kernel = VMHelper.determine_is_pv(self._session,
-                instance.id, first_vdi_ref, disk_image_type,
-                instance.os_type)
+
+        vm_mode = instance.vm_mode and instance.vm_mode.lower()
+        if vm_mode == 'pv':
+            use_pv_kernel = True
+        elif vm_mode in ('hv', 'hvm'):
+            use_pv_kernel = False
+            vm_mode = 'hvm'  # Normalize
+        else:
+            use_pv_kernel = VMHelper.determine_is_pv(self._session,
+                    instance.id, first_vdi_ref, disk_image_type,
+                    instance.os_type)
+            vm_mode = use_pv_kernel and 'pv' or 'hvm'
+
+        if instance.vm_mode != vm_mode:
+            # Update database with normalized (or determined) value
+            db.instance_update(context.get_admin_context(),
+                               instance['id'], {'vm_mode': vm_mode})
+
         vm_ref = VMHelper.create_vm(self._session, instance,
                 kernel, ramdisk, use_pv_kernel)
         VMHelper.create_vbd(session=self._session, vm_ref=vm_ref,