PCI utils

Some basic PCI utilities, like PCI spec match and
address parser, which will be used by multiple PCI
passthrough functionalities.

bp:pci-passthrough-base

Change-Id: I8a77a49c93edf2699bceb6a52dd7f4ae45d577fe
Signed-off-by: Yongli He <yongli.he@intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

nova/exception.py

@@ -1364,3 +1364,7 @@ class ImageDownloadModuleMetaDataError(ImageDownloadModuleError):
 
 class ImageDownloadModuleConfigurationError(ImageDownloadModuleError):
     msg_fmt = _("The module %(module)s is misconfigured: %(reason)s.")
+
+
+class PciDeviceWrongAddressFormat(NovaException):
+    msg_fmt = _("The PCI address %(address)s has an incorrect format.")

nova/pci/pci_utils.py

@@ -0,0 +1,57 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright (c) 2013 Intel, Inc.
+# 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 re
+
+from nova import exception
+
+
+_PCI_ADDRESS_PATTERN = ("^(hex{4}):(hex{2}):(hex{2}).(oct{1})$".
+                                             replace("hex", "[\da-fA-F]").
+                                             replace("oct", "[0-7]"))
+_PCI_ADDRESS_REGEX = re.compile(_PCI_ADDRESS_PATTERN)
+
+
+def pci_device_prop_match(pci_dev, specs):
+    """Check if the pci_dev meet spec requirement
+
+    Specs is a list of PCI device property requirements.
+    An example of device requirement that the PCI should be either:
+    a) Device with vendor_id as 0x8086 and product_id as 0x8259, or
+    b) Device with vendor_id as 0x10de and product_id as 0x10d8:
+
+    [{"vendor_id":"8086", "product_id":"8259"},
+     {"vendor_id":"10de", "product_id":"10d8"}]
+
+    """
+    def _matching_devices(spec):
+        return all(pci_dev.get(k) == v for k, v in spec.iteritems())
+
+    return any(_matching_devices(spec) for spec in specs)
+
+
+def parse_address(address):
+    """
+    Returns (domain, bus, slot, function) from PCI address that is stored in
+    PciDevice DB table.
+    """
+    m = _PCI_ADDRESS_REGEX.match(address)
+    if not m:
+        raise exception.PciDeviceWrongAddressFormat(address=address)
+    return m.groups()

nova/tests/pci/test_pci_utils.py

@@ -0,0 +1,63 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright (c) 2013 Intel, Inc.
+# 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.
+
+from nova import exception
+from nova.pci import pci_utils
+from nova import test
+
+
+class PciDeviceMatchTestCase(test.TestCase):
+    def setUp(self):
+        super(PciDeviceMatchTestCase, self).setUp()
+        self.fake_pci_1 = {'vendor_id': 'v1',
+                           'device_id': 'd1'}
+
+    def test_single_spec_match(self):
+        self.assertTrue(pci_utils.pci_device_prop_match(
+            self.fake_pci_1, [{'vendor_id': 'v1', 'device_id': 'd1'}]))
+
+    def test_multiple_spec_match(self):
+        self.assertTrue(pci_utils.pci_device_prop_match(
+            self.fake_pci_1,
+            [{'vendor_id': 'v1', 'device_id': 'd1'},
+             {'vendor_id': 'v3', 'device_id': 'd3'}]))
+
+    def test_spec_dismatch(self):
+        self.assertFalse(pci_utils.pci_device_prop_match(
+            self.fake_pci_1,
+            [{'vendor_id': 'v4', 'device_id': 'd4'},
+             {'vendor_id': 'v3', 'device_id': 'd3'}]))
+
+    def test_spec_extra_key(self):
+        self.assertFalse(pci_utils.pci_device_prop_match(
+            self.fake_pci_1,
+            [{'vendor_id': 'v1', 'device_id': 'd1', 'wrong_key': 'k1'}]))
+
+
+class PciDeviceAddressParserTestCase(test.TestCase):
+    def test_parse_address(self):
+        self.parse_result = pci_utils.parse_address("0000:04:12.6")
+        self.assertEqual(self.parse_result, ('0000', '04', '12', '6'))
+
+    def test_parse_address_wrong(self):
+        self.assertRaises(exception.PciDeviceWrongAddressFormat,
+            pci_utils.parse_address, "0000:04.12:6")
+
+    def test_parse_address_invalid_character(self):
+        self.assertRaises(exception.PciDeviceWrongAddressFormat,
+            pci_utils.parse_address, "0000:h4.12:6")