Add supports_remote_managed_ports capability

In order to support remote-managed ports the following is needed:

* Nova compute driver needs to support this feature;
* For the Libvirt compute driver, a given host needs to have the right
  version of Libvirt - the one which supports PCI VPD (7.9.0
  https://libvirt.org/news.html#v7-9-0-2021-11-01).

Therefore, this change introduces a new capability to track driver
support for remote-managed ports.

Change-Id: I7ea96fd85d2607e0af0f6918b0b45c58e8bec058

nova/pci/stats.py

@@ -110,6 +110,10 @@ class PciDeviceStats(object):
                                 fields.PciDeviceType.SRIOV_PF,
                                 fields.PciDeviceType.VDPA):
             return
+
+        # A tag is added here rather than at the client side to avoid an
+        # issue with having objects without this tag specified during an
+        # upgrade to the first version that supports handling this tag.
         if pool.get(PCI_REMOTE_MANAGED_TAG) is None:
             # NOTE: tags are compared as strings case-insensitively, see
             # pci_device_prop_match in nova/pci/utils.py.

nova/tests/functional/test_servers_provider_tree.py

@@ -45,6 +45,7 @@ class ProviderTreeTests(integrated_helpers.ProviderUsageBaseTestCase):
             os_traits.COMPUTE_VOLUME_EXTEND,
             os_traits.COMPUTE_VOLUME_MULTI_ATTACH,
             os_traits.COMPUTE_TRUSTED_CERTS,
+            os_traits.COMPUTE_REMOTE_MANAGED_PORTS,
         ]
     ])
 

nova/tests/unit/virt/libvirt/test_driver.py

@@ -885,6 +885,22 @@ class LibvirtConnTestCase(test.NoDBTestCase,
         )
         mock_supports.assert_called_once_with()
 
+    @mock.patch.object(
+        libvirt_driver.LibvirtDriver, '_register_instance_machine_type',
+        new=mock.Mock())
+    @mock.patch.object(
+        host.Host, 'supports_remote_managed_ports',
+        new_callable=mock.PropertyMock)
+    def test_driver_capabilities_remote_managed_ports(self, mock_supports):
+        drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), False)
+        drvr.init_host("dummyhost")
+        self.assertTrue(
+            drvr.capabilities['supports_remote_managed_ports'],
+            "Driver capabilities for 'supports_remote_managed_ports' "
+            "is invalid when host should support this feature"
+        )
+        mock_supports.assert_called_once_with()
+
     def test_driver_raises_on_non_linux_platform(self):
         with utils.temporary_mutation(sys, platform='darwin'):
             self.assertRaises(

nova/tests/unit/virt/libvirt/test_host.py

@@ -1816,6 +1816,16 @@ cg /cgroup/memory cg opt1,opt2 0 0
         """
         self.assertTrue(self.host.supports_secure_boot)
 
+    @mock.patch.object(fakelibvirt.virConnect, "getLibVersion")
+    def test_supports_remote_managed_ports__true(self, mock_libversion):
+        mock_libversion.return_value = 7009000
+        self.assertTrue(self.host.supports_remote_managed_ports)
+
+    @mock.patch.object(fakelibvirt.virConnect, "getLibVersion")
+    def test_supports_remote_managed_ports__false(self, mock_libversion):
+        mock_libversion.return_value = 7008000
+        self.assertFalse(self.host.supports_remote_managed_ports)
+
     @mock.patch.object(host.Host, 'loaders', new_callable=mock.PropertyMock)
     @mock.patch.object(host.Host, 'get_canonical_machine_type')
     def test_get_loader(self, mock_get_mtype, mock_loaders):

nova/virt/driver.py

@@ -126,6 +126,7 @@ CAPABILITY_TRAITS_MAP = {
     "supports_secure_boot": os_traits.COMPUTE_SECURITY_UEFI_SECURE_BOOT,
     "supports_socket_pci_numa_affinity":
         os_traits.COMPUTE_SOCKET_PCI_NUMA_AFFINITY,
+    "supports_remote_managed_ports": os_traits.COMPUTE_REMOTE_MANAGED_PORTS,
 }
 
 
@@ -194,6 +195,7 @@ class ComputeDriver(object):
         "supports_vtpm": False,
         "supports_secure_boot": False,
         "supports_socket_pci_numa_affinity": False,
+        "supports_remote_managed_ports": False,
 
         # Image type support flags
         "supports_image_type_aki": False,

nova/virt/fake.py

@@ -116,6 +116,7 @@ class FakeDriver(driver.ComputeDriver):
         "supports_trusted_certs": True,
         "supports_pcpus": False,
         "supports_accelerators": True,
+        "supports_remote_managed_ports": True,
 
         # Supported image types
         "supports_image_type_raw": True,

nova/virt/hyperv/driver.py

@@ -103,6 +103,7 @@ class HyperVDriver(driver.ComputeDriver):
         "supports_pcpus": False,
         "supports_accelerators": False,
         "supports_secure_boot": True,
+        "supports_remote_managed_ports": False,
 
         # Supported image types
         "supports_image_type_vhd": True,

nova/virt/ironic/driver.py

@@ -164,6 +164,7 @@ class IronicDriver(virt_driver.ComputeDriver):
         "supports_trusted_certs": False,
         "supports_pcpus": False,
         "supports_accelerators": False,
+        "supports_remote_managed_ports": False,
 
         # Image type support flags
         "supports_image_type_aki": False,

nova/virt/libvirt/driver.py

@@ -812,6 +812,8 @@ class LibvirtDriver(driver.ComputeDriver):
         # or UEFI bootloader support in this manner
         self.capabilities.update({
             'supports_secure_boot': self._host.supports_secure_boot,
+            'supports_remote_managed_ports':
+            self._host.supports_remote_managed_ports
         })
 
     def _register_instance_machine_type(self):

nova/virt/libvirt/host.py

@@ -1701,6 +1701,23 @@ class Host(object):
         LOG.debug("No AMD SEV support detected for any (arch, machine_type)")
         return self._supports_amd_sev
 
+    @property
+    def supports_remote_managed_ports(self) -> bool:
+        """Determine if the host supports remote managed ports.
+
+        Returns a boolean indicating whether remote managed ports are
+        possible to use on this host.
+
+        The check is based on a Libvirt version which added support for
+        parsing and exposing PCI VPD since a card serial number (if present in
+        the VPD) since the use of remote managed ports depends on this.
+        https://libvirt.org/news.html#v7-9-0-2021-11-01
+
+        The actual presence of a card serial number for a particular device
+        is meant to be checked elsewhere.
+        """
+        return self.has_min_version(lv_ver=(7, 9, 0))
+
     @property
     def loaders(self) -> ty.List[dict]:
         """Retrieve details of loader configuration for the host.

nova/virt/powervm/driver.py

@@ -82,6 +82,7 @@ class PowerVMDriver(driver.ComputeDriver):
             'supports_vtpm': False,
             'supports_secure_boot': False,
             'supports_socket_pci_numa_affinity': False,
+            'supports_remote_managed_ports': False,
 
             # Supported image types
             "supports_image_type_aki": False,

nova/virt/vmwareapi/driver.py

@@ -72,6 +72,7 @@ class VMwareVCDriver(driver.ComputeDriver):
         "supports_trusted_certs": False,
         "supports_pcpus": False,
         "supports_accelerators": False,
+        "supports_remote_managed_ports": False,
 
         # Image type support flags
         "supports_image_type_aki": False,

nova/virt/zvm/driver.py

@@ -46,6 +46,7 @@ class ZVMDriver(driver.ComputeDriver):
     """z/VM implementation of ComputeDriver."""
     capabilities = {
         "supports_pcpus": False,
+        "supports_remote_managed_ports": False,
 
         # Image type support flags
         "supports_image_type_aki": False,