# Copyright (c) 2012 OpenStack Foundation
# 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.

import copy

import mock
from oslo_serialization import jsonutils
from oslo_utils.fixture import uuidsentinel

from nova.compute import vm_states
from nova import context
from nova import objects
from nova.objects import fields
from nova.pci import manager
from nova import test
from nova.tests.unit.pci import fakes as pci_fakes


fake_pci = {
    'compute_node_id': 1,
    'address': '0000:00:00.1',
    'product_id': 'p',
    'vendor_id': 'v',
    'request_id': None,
    'status': fields.PciDeviceStatus.AVAILABLE,
    'dev_type': fields.PciDeviceType.STANDARD,
    'parent_addr': None,
    'numa_node': 0}
fake_pci_1 = dict(fake_pci, address='0000:00:00.2',
                  product_id='p1', vendor_id='v1')
fake_pci_2 = dict(fake_pci, address='0000:00:00.3')

fake_pci_3 = dict(fake_pci, address='0000:00:01.1',
                  dev_type=fields.PciDeviceType.SRIOV_PF,
                  vendor_id='v2', product_id='p2', numa_node=None)
fake_pci_4 = dict(fake_pci, address='0000:00:02.1',
                  dev_type=fields.PciDeviceType.SRIOV_VF,
                  parent_addr='0000:00:01.1',
                  vendor_id='v2', product_id='p2', numa_node=None)
fake_pci_5 = dict(fake_pci, address='0000:00:02.2',
                  dev_type=fields.PciDeviceType.SRIOV_VF,
                  parent_addr='0000:00:01.1',
                  vendor_id='v2', product_id='p2', numa_node=None)

fake_db_dev = {
    'created_at': None,
    'updated_at': None,
    'deleted_at': None,
    'deleted': None,
    'id': 1,
    'uuid': uuidsentinel.pci_device1,
    'compute_node_id': 1,
    'address': '0000:00:00.1',
    'vendor_id': 'v',
    'product_id': 'p',
    'numa_node': 1,
    'dev_type': fields.PciDeviceType.STANDARD,
    'status': fields.PciDeviceStatus.AVAILABLE,
    'dev_id': 'i',
    'label': 'l',
    'instance_uuid': None,
    'extra_info': '{}',
    'request_id': None,
    'parent_addr': None,
    }
fake_db_dev_1 = dict(fake_db_dev, vendor_id='v1',
                     uuid=uuidsentinel.pci_device1,
                     product_id='p1', id=2,
                     address='0000:00:00.2',
                     numa_node=0)
fake_db_dev_2 = dict(fake_db_dev, id=3, address='0000:00:00.3',
                     uuid=uuidsentinel.pci_device2,
                     numa_node=None, parent_addr='0000:00:00.1')
fake_db_devs = [fake_db_dev, fake_db_dev_1, fake_db_dev_2]

fake_db_dev_3 = dict(fake_db_dev, id=4, address='0000:00:01.1',
                     uuid=uuidsentinel.pci_device3,
                     vendor_id='v2', product_id='p2',
                     numa_node=None, dev_type=fields.PciDeviceType.SRIOV_PF)
fake_db_dev_4 = dict(fake_db_dev, id=5, address='0000:00:02.1',
                     uuid=uuidsentinel.pci_device4,
                     numa_node=None, dev_type=fields.PciDeviceType.SRIOV_VF,
                     vendor_id='v2', product_id='p2',
                     parent_addr='0000:00:01.1')
fake_db_dev_5 = dict(fake_db_dev, id=6, address='0000:00:02.2',
                     uuid=uuidsentinel.pci_device5,
                     numa_node=None, dev_type=fields.PciDeviceType.SRIOV_VF,
                     vendor_id='v2', product_id='p2',
                     parent_addr='0000:00:01.1')
fake_db_devs_tree = [fake_db_dev_3, fake_db_dev_4, fake_db_dev_5]

fake_pci_requests = [
    {'count': 1,
     'spec': [{'vendor_id': 'v'}]},
    {'count': 1,
     'spec': [{'vendor_id': 'v1'}]}]


class PciDevTrackerTestCase(test.NoDBTestCase):
    def _create_fake_instance(self):
        self.inst = objects.Instance()
        self.inst.uuid = uuidsentinel.instance1
        self.inst.pci_devices = objects.PciDeviceList()
        self.inst.vm_state = vm_states.ACTIVE
        self.inst.task_state = None
        self.inst.numa_topology = None

    def _fake_get_pci_devices(self, ctxt, node_id):
        return self.fake_devs

    def _fake_pci_device_update(self, ctxt, node_id, address, value):
        self.update_called += 1
        self.called_values = value
        fake_return = copy.deepcopy(fake_db_dev)
        return fake_return

    def _fake_pci_device_destroy(self, ctxt, node_id, address):
        self.destroy_called += 1

    def _create_pci_requests_object(self, requests,
                                    instance_uuid=None):
        instance_uuid = instance_uuid or uuidsentinel.instance1
        pci_reqs = []
        for request in requests:
            pci_req_obj = objects.InstancePCIRequest(count=request['count'],
                                                     spec=request['spec'])
            pci_reqs.append(pci_req_obj)
        return objects.InstancePCIRequests(
                instance_uuid=instance_uuid,
                requests=pci_reqs)

    def _create_tracker(self, fake_devs):
        self.fake_devs = fake_devs
        self.tracker = manager.PciDevTracker(
            self.fake_context, objects.ComputeNode(id=1, numa_topology=None))

    def setUp(self):
        super(PciDevTrackerTestCase, self).setUp()
        self.fake_context = context.get_admin_context()
        self.fake_devs = fake_db_devs[:]
        self.stub_out('nova.db.api.pci_device_get_all_by_node',
            self._fake_get_pci_devices)
        # The fake_pci_whitelist must be called before creating the fake
        # devices
        patcher = pci_fakes.fake_pci_whitelist()
        self.addCleanup(patcher.stop)
        self._create_fake_instance()
        self._create_tracker(fake_db_devs[:])

    def test_pcidev_tracker_create(self):
        self.assertEqual(len(self.tracker.pci_devs), 3)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 3)
        self.assertEqual(list(self.tracker.stale), [])
        self.assertEqual(len(self.tracker.stats.pools), 3)
        self.assertEqual(self.tracker.node_id, 1)
        for dev in self.tracker.pci_devs:
            self.assertIsNone(dev.parent_device)
            self.assertEqual(dev.child_devices, [])

    def test_pcidev_tracker_create_device_tree(self):
        self._create_tracker(fake_db_devs_tree)

        self.assertEqual(len(self.tracker.pci_devs), 3)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 3)
        self.assertEqual(list(self.tracker.stale), [])
        self.assertEqual(len(self.tracker.stats.pools), 2)
        self.assertEqual(self.tracker.node_id, 1)
        pf = [dev for dev in self.tracker.pci_devs
              if dev.dev_type == fields.PciDeviceType.SRIOV_PF].pop()
        vfs = [dev for dev in self.tracker.pci_devs
               if dev.dev_type == fields.PciDeviceType.SRIOV_VF]
        self.assertEqual(2, len(vfs))

        # Assert we build the device tree correctly
        self.assertEqual(vfs, pf.child_devices)
        for vf in vfs:
            self.assertEqual(vf.parent_device, pf)

    def test_pcidev_tracker_create_device_tree_pf_only(self):
        self._create_tracker([fake_db_dev_3])

        self.assertEqual(len(self.tracker.pci_devs), 1)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 1)
        self.assertEqual(list(self.tracker.stale), [])
        self.assertEqual(len(self.tracker.stats.pools), 1)
        self.assertEqual(self.tracker.node_id, 1)
        pf = self.tracker.pci_devs[0]
        self.assertIsNone(pf.parent_device)
        self.assertEqual([], pf.child_devices)

    def test_pcidev_tracker_create_device_tree_vf_only(self):
        self._create_tracker([fake_db_dev_4])

        self.assertEqual(len(self.tracker.pci_devs), 1)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 1)
        self.assertEqual(list(self.tracker.stale), [])
        self.assertEqual(len(self.tracker.stats.pools), 1)
        self.assertEqual(self.tracker.node_id, 1)
        vf = self.tracker.pci_devs[0]
        self.assertIsNone(vf.parent_device)
        self.assertEqual([], vf.child_devices)

    @mock.patch('nova.pci.whitelist.Whitelist.device_assignable',
                return_value=True)
    def test_update_devices_from_hypervisor_resources(self, _mock_dev_assign):
        fake_pci_devs = [copy.deepcopy(fake_pci_4), copy.deepcopy(fake_pci_5)]
        fake_pci_devs_json = jsonutils.dumps(fake_pci_devs)
        tracker = manager.PciDevTracker(
            self.fake_context, objects.ComputeNode(id=1, numa_topology=None))
        tracker.update_devices_from_hypervisor_resources(fake_pci_devs_json)
        self.assertEqual(5, len(tracker.pci_devs))

    @mock.patch("nova.pci.manager.LOG.debug")
    def test_update_devices_from_hypervisor_resources_32bit_domain(
            self, mock_debug):
        self.flags(
            group='pci',
            passthrough_whitelist=[
                '{"product_id":"2032", "vendor_id":"8086"}'])
        # There are systems where 32 bit PCI domain is used. See bug 1897528
        # for example. While nova (and qemu) does not support assigning such
        # devices but the existence of such device in the system should not
        # lead to an error.
        fake_pci = {
            'compute_node_id': 1,
            'address': '10000:00:02.0',
            'product_id': '2032',
            'vendor_id': '8086',
            'request_id': None,
            'status': fields.PciDeviceStatus.AVAILABLE,
            'dev_type': fields.PciDeviceType.STANDARD,
            'parent_addr': None,
            'numa_node': 0}

        fake_pci_devs = [fake_pci]
        fake_pci_devs_json = jsonutils.dumps(fake_pci_devs)
        tracker = manager.PciDevTracker(
            self.fake_context, objects.ComputeNode(id=1, numa_topology=None))
        # We expect that the device with 32bit PCI domain is ignored, so we'll
        # have only the 3 original fake devs
        tracker.update_devices_from_hypervisor_resources(fake_pci_devs_json)
        self.assertEqual(3, len(tracker.pci_devs))
        mock_debug.assert_called_once_with(
            'Skipping PCI device %s reported by the hypervisor: %s',
            {'address': '10000:00:02.0', 'parent_addr': None},
            'The property domain (10000) is greater than the maximum '
            'allowable value (FFFF).')

    def test_set_hvdev_new_dev(self):
        fake_pci_3 = dict(fake_pci, address='0000:00:00.4', vendor_id='v2')
        fake_pci_devs = [copy.deepcopy(fake_pci), copy.deepcopy(fake_pci_1),
                         copy.deepcopy(fake_pci_2), copy.deepcopy(fake_pci_3)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.assertEqual(len(self.tracker.pci_devs), 4)
        self.assertEqual(set([dev.address for
                              dev in self.tracker.pci_devs]),
                         set(['0000:00:00.1', '0000:00:00.2',
                              '0000:00:00.3', '0000:00:00.4']))
        self.assertEqual(set([dev.vendor_id for
                              dev in self.tracker.pci_devs]),
                         set(['v', 'v1', 'v2']))

    def test_set_hvdev_new_dev_tree_maintained(self):
        # Make sure the device tree is properly maintained when there are new
        # devices reported by the driver
        self._create_tracker(fake_db_devs_tree)

        fake_new_device = dict(fake_pci_5, id=12, address='0000:00:02.3')
        fake_pci_devs = [copy.deepcopy(fake_pci_3),
                         copy.deepcopy(fake_pci_4),
                         copy.deepcopy(fake_pci_5),
                         copy.deepcopy(fake_new_device)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.assertEqual(len(self.tracker.pci_devs), 4)

        pf = [dev for dev in self.tracker.pci_devs
              if dev.dev_type == fields.PciDeviceType.SRIOV_PF].pop()
        vfs = [dev for dev in self.tracker.pci_devs
               if dev.dev_type == fields.PciDeviceType.SRIOV_VF]
        self.assertEqual(3, len(vfs))

        # Assert we build the device tree correctly
        self.assertEqual(vfs, pf.child_devices)
        for vf in vfs:
            self.assertEqual(vf.parent_device, pf)

    def test_set_hvdev_changed(self):
        fake_pci_v2 = dict(fake_pci, address='0000:00:00.2', vendor_id='v1')
        fake_pci_devs = [copy.deepcopy(fake_pci), copy.deepcopy(fake_pci_2),
                         copy.deepcopy(fake_pci_v2)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.assertEqual(set([dev.vendor_id for
                             dev in self.tracker.pci_devs]),
                         set(['v', 'v1']))

    def test_set_hvdev_remove(self):
        self.tracker._set_hvdevs([fake_pci])
        self.assertEqual(
            len([dev for dev in self.tracker.pci_devs
                 if dev.status == fields.PciDeviceStatus.REMOVED]),
            2)

    def test_set_hvdev_remove_tree_maintained(self):
        # Make sure the device tree is properly maintained when there are
        # devices removed from the system (not reported by the driver but known
        # from previous scans)
        self._create_tracker(fake_db_devs_tree)

        fake_pci_devs = [copy.deepcopy(fake_pci_3), copy.deepcopy(fake_pci_4)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.assertEqual(
            2,
            len([dev for dev in self.tracker.pci_devs
                 if dev.status != fields.PciDeviceStatus.REMOVED]))
        pf = [dev for dev in self.tracker.pci_devs
              if dev.dev_type == fields.PciDeviceType.SRIOV_PF].pop()
        vfs = [dev for dev in self.tracker.pci_devs
               if (dev.dev_type == fields.PciDeviceType.SRIOV_VF and
                   dev.status != fields.PciDeviceStatus.REMOVED)]
        self.assertEqual(1, len(vfs))

        self.assertEqual(vfs, pf.child_devices)
        self.assertEqual(vfs[0].parent_device, pf)

    def test_set_hvdev_remove_tree_maintained_with_allocations(self):
        # Make sure the device tree is properly maintained when there are
        # devices removed from the system that are allocated to vms.

        all_devs = fake_db_devs_tree[:]
        self._create_tracker(all_devs)
        # we start with 3 devices
        self.assertEqual(
            3,
            len([dev for dev in self.tracker.pci_devs
                 if dev.status != fields.PciDeviceStatus.REMOVED]))
        # we then allocate one device
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v2'}]}])
        # NOTE(sean-k-mooney): context, pci request, numa topology
        claimed_dev = self.tracker.claim_instance(
            mock.sentinel.context, pci_requests_obj, None)[0]

        self.tracker._set_hvdevs(all_devs)
        # and assert that no devices were removed
        self.assertEqual(
            0,
            len([dev for dev in self.tracker.pci_devs
                 if dev.status == fields.PciDeviceStatus.REMOVED]))
        # we then try to remove the allocated device from the set reported
        # by the driver.
        fake_pci_devs = [dev for dev in all_devs
                         if dev['address'] != claimed_dev.address]
        with mock.patch("nova.pci.manager.LOG.warning") as log:
            self.tracker._set_hvdevs(fake_pci_devs)
            log.assert_called_once()
            args = log.call_args_list[0][0]  # args of first call
            self.assertIn('Unable to remove device with', args[0])
        # and assert no devices are removed from the tracker
        self.assertEqual(
            0,
            len([dev for dev in self.tracker.pci_devs
                 if dev.status == fields.PciDeviceStatus.REMOVED]))
        # free the device that was allocated and update tracker again
        self.tracker._free_device(claimed_dev)
        self.tracker._set_hvdevs(fake_pci_devs)
        # and assert that one device is removed from the tracker
        self.assertEqual(
            1,
            len([dev for dev in self.tracker.pci_devs
                 if dev.status == fields.PciDeviceStatus.REMOVED]))

    def test_set_hvdev_changed_stal(self):
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v1'}]}])
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        fake_pci_3 = dict(fake_pci, address='0000:00:00.2', vendor_id='v2')
        fake_pci_devs = [copy.deepcopy(fake_pci), copy.deepcopy(fake_pci_2),
                         copy.deepcopy(fake_pci_3)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.assertEqual(len(self.tracker.stale), 1)
        self.assertEqual(self.tracker.stale['0000:00:00.2']['vendor_id'], 'v2')

    def test_update_pci_for_instance_active(self):
        pci_requests_obj = self._create_pci_requests_object(fake_pci_requests)
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.assertEqual(len(self.tracker.claims[self.inst['uuid']]), 2)
        self.tracker.update_pci_for_instance(None, self.inst, sign=1)
        self.assertEqual(len(self.tracker.allocations[self.inst['uuid']]), 2)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 1)
        self.assertEqual(free_devs[0].vendor_id, 'v')

    def test_update_pci_for_instance_fail(self):
        pci_requests = copy.deepcopy(fake_pci_requests)
        pci_requests[0]['count'] = 4
        pci_requests_obj = self._create_pci_requests_object(pci_requests)
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.assertEqual(len(self.tracker.claims[self.inst['uuid']]), 0)
        devs = self.tracker.update_pci_for_instance(None,
                                                    self.inst,
                                                    sign=1)
        self.assertEqual(len(self.tracker.allocations[self.inst['uuid']]), 0)
        self.assertIsNone(devs)

    def test_pci_claim_instance_with_numa(self):
        fake_db_dev_3 = dict(fake_db_dev_1, id=4, address='0000:00:00.4')
        fake_devs_numa = copy.deepcopy(fake_db_devs)
        fake_devs_numa.append(fake_db_dev_3)
        self.tracker = manager.PciDevTracker(
            mock.sentinel.context,
            objects.ComputeNode(id=1, numa_topology=None))
        self.tracker._set_hvdevs(fake_devs_numa)
        pci_requests = copy.deepcopy(fake_pci_requests)[:1]
        pci_requests[0]['count'] = 2
        pci_requests_obj = self._create_pci_requests_object(pci_requests)
        self.inst.numa_topology = objects.InstanceNUMATopology(
                    cells=[objects.InstanceNUMACell(
                        id=1, cpuset=set([1, 2]), memory=512)])
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj,
                                    self.inst.numa_topology)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(2, len(free_devs))
        self.assertEqual('v1', free_devs[0].vendor_id)
        self.assertEqual('v1', free_devs[1].vendor_id)

    def test_pci_claim_instance_with_numa_fail(self):
        pci_requests_obj = self._create_pci_requests_object(fake_pci_requests)
        self.inst.numa_topology = objects.InstanceNUMATopology(
                    cells=[objects.InstanceNUMACell(
                        id=1, cpuset=set([1, 2]), memory=512)])
        self.assertIsNone(self.tracker.claim_instance(
                            mock.sentinel.context,
                            pci_requests_obj,
                            self.inst.numa_topology))

    def test_update_pci_for_instance_deleted(self):
        pci_requests_obj = self._create_pci_requests_object(fake_pci_requests)
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 1)
        self.inst.vm_state = vm_states.DELETED
        self.tracker.update_pci_for_instance(None, self.inst, -1)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 3)
        self.assertEqual(set([dev.vendor_id for
                              dev in self.tracker.pci_devs]),
                         set(['v', 'v1']))

    @mock.patch.object(objects.PciDevice, 'should_migrate_data',
                       return_value=False)
    def test_save(self, migrate_mock):
        self.stub_out(
                'nova.db.api.pci_device_update',
                self._fake_pci_device_update)
        fake_pci_v3 = dict(fake_pci, address='0000:00:00.2', vendor_id='v3')
        fake_pci_devs = [copy.deepcopy(fake_pci), copy.deepcopy(fake_pci_2),
                         copy.deepcopy(fake_pci_v3)]
        self.tracker._set_hvdevs(fake_pci_devs)
        self.update_called = 0
        self.tracker.save(self.fake_context)
        self.assertEqual(self.update_called, 3)

    def test_save_removed(self):
        self.stub_out(
                'nova.db.api.pci_device_update',
                self._fake_pci_device_update)
        self.stub_out(
                'nova.db.api.pci_device_destroy',
                self._fake_pci_device_destroy)
        self.destroy_called = 0
        self.assertEqual(len(self.tracker.pci_devs), 3)
        dev = self.tracker.pci_devs[0]
        self.update_called = 0
        dev.remove()
        self.tracker.save(self.fake_context)
        self.assertEqual(len(self.tracker.pci_devs), 2)
        self.assertEqual(self.destroy_called, 1)

    def test_clean_usage(self):
        inst_2 = copy.copy(self.inst)
        inst_2.uuid = uuidsentinel.instance2
        migr = {'instance_uuid': 'uuid2', 'vm_state': vm_states.BUILDING}

        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v'}]}])
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.tracker.update_pci_for_instance(None, self.inst, sign=1)
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v1'}]}],
            instance_uuid=inst_2.uuid)
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.tracker.update_pci_for_instance(None, inst_2, sign=1)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 1)
        self.assertEqual(free_devs[0].vendor_id, 'v')

        self.tracker.clean_usage([self.inst], [migr])
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 2)
        self.assertEqual(
            set([dev.vendor_id for dev in free_devs]),
            set(['v', 'v1']))

    def test_clean_usage_no_request_match_no_claims(self):
        # Tests the case that there is no match for the request so the
        # claims mapping is set to None for the instance when the tracker
        # calls clean_usage.
        self.tracker.update_pci_for_instance(None, self.inst, sign=1)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(3, len(free_devs))
        self.tracker.clean_usage([], [])
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(3, len(free_devs))
        self.assertEqual(
            set([dev.address for dev in free_devs]),
            set(['0000:00:00.1', '0000:00:00.2', '0000:00:00.3']))

    def test_free_devices(self):
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v'}]}])
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.tracker.update_pci_for_instance(None, self.inst, sign=1)

        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 2)

        self.tracker.free_instance(None, self.inst)
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(free_devs), 3)

    def test_free_device(self):
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v'}]}])
        self.tracker.claim_instance(mock.sentinel.context,
                                    pci_requests_obj, None)
        self.tracker.update_pci_for_instance(None, self.inst, sign=1)
        free_pci_device_ids = (
            [dev.id for dev in self.tracker.pci_stats.get_free_devs()])
        self.assertEqual(2, len(free_pci_device_ids))
        allocated_devs = manager.get_instance_pci_devs(self.inst)
        pci_device = allocated_devs[0]
        self.assertNotIn(pci_device.id, free_pci_device_ids)
        instance_uuid = self.inst['uuid']
        self.assertIn(pci_device, self.tracker.allocations[instance_uuid])
        self.tracker.free_device(pci_device, self.inst)
        free_pci_device_ids = (
            [dev.id for dev in self.tracker.pci_stats.get_free_devs()])
        self.assertEqual(3, len(free_pci_device_ids))
        self.assertIn(pci_device.id, free_pci_device_ids)
        self.assertIsNone(self.tracker.allocations.get(instance_uuid))

    def test_free_instance_claims(self):
        # Create an InstancePCIRequest object
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v'}]}])

        # Claim a single PCI device
        claimed_devs = self.tracker.claim_instance(mock.sentinel.context,
                                                   pci_requests_obj, None)

        # Assert we have exactly one claimed device for the given instance.
        claimed_dev = claimed_devs[0]
        instance_uuid = self.inst['uuid']
        self.assertEqual(1, len(self.tracker.claims.get(instance_uuid)))
        self.assertIn(claimed_dev.id,
                      [pci_dev.id for pci_dev in
                       self.tracker.claims.get(instance_uuid)])
        self.assertIsNone(self.tracker.allocations.get(instance_uuid))

        # Free instance claims
        self.tracker.free_instance_claims(mock.sentinel.context, self.inst)

        # Assert no claims for instance and all PCI devices are free
        self.assertIsNone(self.tracker.claims.get(instance_uuid))
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(fake_db_devs), len(free_devs))

    def test_free_instance_allocations(self):
        # Create an InstancePCIRequest object
        pci_requests_obj = self._create_pci_requests_object(
            [{'count': 1, 'spec': [{'vendor_id': 'v'}]}])
        # Allocate a single PCI device
        allocated_devs = self.tracker.claim_instance(mock.sentinel.context,
                                                     pci_requests_obj, None)
        self.tracker.allocate_instance(self.inst)

        # Assert we have exactly one allocated device for the given instance.
        allocated_dev = allocated_devs[0]
        instance_uuid = self.inst['uuid']
        self.assertIsNone(self.tracker.claims.get(instance_uuid))
        self.assertEqual(1, len(self.tracker.allocations.get(instance_uuid)))
        self.assertIn(allocated_dev.id,
                      [pci_dev.id for pci_dev in
                       self.tracker.allocations.get(instance_uuid)])

        # Free instance allocations and assert claims did not change
        self.tracker.free_instance_allocations(mock.sentinel.context,
                                               self.inst)
        # Assert all PCI devices are free.
        self.assertIsNone(self.tracker.allocations.get(instance_uuid))
        free_devs = self.tracker.pci_stats.get_free_devs()
        self.assertEqual(len(fake_db_devs), len(free_devs))


class PciGetInstanceDevs(test.NoDBTestCase):

    def test_get_devs_object(self):
        def _fake_obj_load_attr(foo, attrname):
            if attrname == 'pci_devices':
                self.load_attr_called = True
                foo.pci_devices = objects.PciDeviceList()

        self.stub_out(
                'nova.objects.Instance.obj_load_attr',
                _fake_obj_load_attr)

        self.load_attr_called = False
        manager.get_instance_pci_devs(objects.Instance())
        self.assertTrue(self.load_attr_called)

    def test_get_devs_no_pci_devices(self):
        inst = objects.Instance(pci_devices=None)
        self.assertEqual([], manager.get_instance_pci_devs(inst))
