Fix detach SR-IOV when using LibvirtConfigGuestHostdevPCI

This patch fixes an issue which was introduced by this
change If3edc1965c01a077eb61984a442e0d778d870d75.
Usually the vif config is of type LibvirtConfigGuestInterface,
but some vif use LibvirtConfigGuestHostdevPCI config
(e.g.  the ib_hostdev). The difference is that
LibvirtConfigGuestInterface keeps the pci address in source_dev
while LibvirtConfigGuestHostdevPCI has domain, bus, slot and
function, instead of relying on the vif config type we can take the
pci address for the neutron port.

Closes-Bug: #1560860

Change-Id: I62a7ff16f1c9c5da923451520fbeeabb5cc0c5c6
(cherry picked from commit f15d9a9693b19393fcde84cf4bc6f044d39ffdca)

2 files changed, 27 insertions, 24 deletions

diff --git a/nova/tests/unit/virt/libvirt/test_driver.py b/nova/tests/unit/virt/libvirt/test_driver.py
index 2857264170..0dc459190b 100644
--- a/nova/tests/unit/virt/libvirt/test_driver.py
+++ b/nova/tests/unit/virt/libvirt/test_driver.py
@@ -10357,15 +10357,11 @@ class LibvirtConnTestCase(test.NoDBTestCase):
 
     @mock.patch.object(host.Host,
                        'has_min_version', return_value=True)
-    @mock.patch.object(FakeVirtDomain, 'detachDeviceFlags')
-    @mock.patch.object(utils, 'get_image_from_system_metadata',
-                       return_value=None)
-    def test_detach_sriov_ports(self,
-                                mock_get_image_metadata,
-                                mock_detachDeviceFlags,
-                                mock_has_min_version):
+    def _test_detach_sriov_ports(self,
+                                 mock_has_min_version, vif_type):
         instance = objects.Instance(**self.test_instance)
 
+        expeted_pci_slot = "0000:00:00.0"
         network_info = _fake_network_info(self, 1)
         network_info[0]['vnic_type'] = network_model.VNIC_TYPE_DIRECT
         # some more adjustments for the fake network_info so that
@@ -10374,27 +10370,37 @@ class LibvirtConnTestCase(test.NoDBTestCase):
         # and most importantly the pci_slot which is translated to
         # cfg.source_dev, then to PciDevice.address and sent to
         # _detach_pci_devices
-        network_info[0]['profile'] = dict(pci_slot="0000:00:00.0")
-        network_info[0]['type'] = "hw_veb"
+        network_info[0]['profile'] = dict(pci_slot=expeted_pci_slot)
+        network_info[0]['type'] = vif_type
         network_info[0]['details'] = dict(vlan="2145")
         instance.info_cache = objects.InstanceInfoCache(
             network_info=network_info)
         # fill the pci_devices of the instance so that
         # pci_manager.get_instance_pci_devs will not return an empty list
         # which will eventually fail the assertion for detachDeviceFlags
+        expected_pci_device_obj = (
+            objects.PciDevice(address=expeted_pci_slot, request_id=None))
         instance.pci_devices = objects.PciDeviceList()
-        instance.pci_devices.objects = [
-            objects.PciDevice(address='0000:00:00.0', request_id=None)
-        ]
+        instance.pci_devices.objects = [expected_pci_device_obj]
 
         domain = FakeVirtDomain()
         drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
         guest = libvirt_guest.Guest(domain)
 
-        drvr._detach_sriov_ports(self.context, instance, guest)
-        mock_get_image_metadata.assert_called_once_with(
-            instance.system_metadata)
-        self.assertTrue(mock_detachDeviceFlags.called)
+        with mock.patch.object(drvr, '_detach_pci_devices') as mock_detach_pci:
+            drvr._detach_sriov_ports(self.context, instance, guest)
+            mock_detach_pci.assert_called_once_with(
+                guest, [expected_pci_device_obj])
+
+    def test_detach_sriov_ports_interface_interface_hostdev(self):
+        # Note: test detach_sriov_ports method for vif with config
+        # LibvirtConfigGuestInterface
+        self._test_detach_sriov_ports(vif_type="hw_veb")
+
+    def test_detach_sriov_ports_interface_pci_hostdev(self):
+        # Note: test detach_sriov_ports method for vif with config
+        # LibvirtConfigGuestHostdevPCI
+        self._test_detach_sriov_ports(vif_type="ib_hostdev")
 
     @mock.patch.object(host.Host, 'has_min_version', return_value=True)
     @mock.patch.object(FakeVirtDomain, 'detachDeviceFlags')
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index f48184a26d..3dce6593f2 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -3413,16 +3413,13 @@ class LibvirtDriver(driver.ComputeDriver):
                 raise exception.PciDeviceDetachFailed(reason=reason,
                                                       dev=network_info)
 
-            image_meta = objects.ImageMeta.from_instance(instance)
+            # In case of SR-IOV vif types we create pci request per SR-IOV port
+            # Therefore we can trust that pci_slot value in the vif is correct.
             sriov_pci_addresses = [
-                self.vif_driver.get_config(instance,
-                                           vif,
-                                           image_meta,
-                                           instance.flavor,
-                                           CONF.libvirt.virt_type,
-                                           self._host).source_dev
+                vif['profile']['pci_slot']
                 for vif in network_info
-                if vif['vnic_type'] in network_model.VNIC_TYPES_SRIOV
+                if vif['vnic_type'] in network_model.VNIC_TYPES_SRIOV and
+                   vif['profile'].get('pci_slot') is not None
             ]
 
             # use detach_pci_devices to avoid failure in case of