GSO: TAP/VHOST use case

Signed-off-by: pmikus <pmikus@cisco.com>
Change-Id: Ibafaaca4438587284d1e255c764f0701002941e8

1 files changed, 70 insertions, 4 deletions

diff --git a/resources/libraries/python/Tap.py b/resources/libraries/python/Tap.py
index 041a774c0b..c729d602b1 100644
--- a/resources/libraries/python/Tap.py
+++ b/resources/libraries/python/Tap.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2019 Cisco and/or its affiliates.
+# Copyright (c) 2021 Cisco and/or its affiliates.
 # 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:
@@ -13,6 +13,8 @@
 
 """Tap utilities library."""
 
+from enum import IntEnum
+
 from robot.api import logger
 
 from resources.libraries.python.Constants import Constants
@@ -22,21 +24,43 @@ from resources.libraries.python.PapiExecutor import PapiSocketExecutor
 from resources.libraries.python.topology import Topology
 
 
+class TapFeaturesFlags(IntEnum):
+    """TAP Features Flags."""
+    TAP_API_FLAG_GSO = 1
+    TAP_API_FLAG_CSUM_OFFLOAD = 2
+    TAP_API_FLAG_PERSIST = 4
+    TAP_API_FLAG_ATTACH = 8
+    TAP_API_FLAG_TUN = 16
+    TAP_API_FLAG_GRO_COALESCE = 32
+    TAP_API_FLAG_PACKED = 64
+    TAP_API_FLAG_IN_ORDER = 128
+
+
 class Tap:
     """Tap utilities."""
 
     @staticmethod
-    def add_tap_interface(node, tap_name, mac=None, num_rx_queues=1):
+    def add_tap_interface(
+            node, tap_name, mac=None, host_namespace=None, num_rx_queues=1,
+            rxq_size=0, txq_size=0, tap_feature_mask=0):
         """Add tap interface with name and optionally with MAC.
 
         :param node: Node to add tap on.
         :param tap_name: Tap interface name for linux tap.
         :param mac: Optional MAC address for VPP tap.
+        :param host_namespace: Namespace.
         :param num_rx_queues: Number of RX queues.
+        :param rxq_size: Size of RXQ (0 = Default API; 256 = Default VPP).
+        :param txq_size: Size of TXQ (0 = Default API; 256 = Default VPP).
+        :param tap_feature_mask: Mask of tap features to be enabled.
         :type node: dict
         :type tap_name: str
         :type mac: str
+        :type host_namespace: str
         :type num_rx_queues: int
+        :type rxq_size: int
+        :type txq_size: int
+        :type tap_feature_mask: int
         :returns: Returns a interface index.
         :rtype: int
         """
@@ -46,16 +70,20 @@ class Tap:
             use_random_mac=bool(mac is None),
             mac_address=L2Util.mac_to_bin(mac) if mac else None,
             num_rx_queues=int(num_rx_queues),
+            tx_ring_sz=int(txq_size),
+            rx_ring_sz=int(rxq_size),
             host_mtu_set=False,
             host_mac_addr_set=False,
             host_ip4_prefix_set=False,
             host_ip6_prefix_set=False,
             host_ip4_gw_set=False,
             host_ip6_gw_set=False,
-            host_namespace_set=False,
+            host_namespace_set=bool(host_namespace),
+            host_namespace=host_namespace,
             host_if_name_set=True,
             host_if_name=tap_name,
-            host_bridge_set=False
+            host_bridge_set=False,
+            tap_flags=tap_feature_mask
         )
         err_msg = f"Failed to create tap interface {tap_name} " \
             f"on host {node[u'host']}"
@@ -152,3 +180,41 @@ class Tap:
 
         logger.debug(f"TAP data:\n{data}")
         return data
+
+
+class TapFeatureMask:
+    """Tap features utilities"""
+
+    @staticmethod
+    def create_tap_feature_mask(**kwargs):
+        """Create tap feature mask with feature bits set according to kwargs.
+        :param kwargs: Key-value pairs of feature names and it's state
+        :type kwargs: dict
+        """
+        tap_feature_mask = 0
+
+        if u"all" in kwargs and kwargs[u"all"] is True:
+            for tap_feature_flag in TapFeaturesFlags:
+                tap_feature_mask |= 1 << (tap_feature_flag.value - 1)
+        else:
+            for feature_name, enabled in kwargs.items():
+                tap_feature_name = u"TAP_API_FLAG_" + feature_name.upper()
+                if tap_feature_name not in TapFeaturesFlags.__members__:
+                    raise ValueError(u"Unsupported tap feature flag name")
+                if enabled:
+                    tap_feature_mask |= \
+                        1 << (TapFeaturesFlags[tap_feature_name].value - 1)
+
+        return tap_feature_mask
+
+    @staticmethod
+    def is_feature_enabled(tap_feature_mask, tap_feature_flag):
+        """Checks if concrete tap feature is enabled within
+         tap_feature_mask
+        :param tap_feature_mask: Mask of enabled tap features
+        :param tap_feature_flag: Checked tap feature
+        :type tap_feature_mask: int
+        :type tap_feature_flag: TapFeaturesFlags
+        """
+        feature_flag_bit = 1 << tap_feature_flag.value
+        return (tap_feature_mask & feature_flag_bit) > 0