ksft_setup_loopback.sh

  1#!/bin/bash
  2# SPDX-License-Identifier: GPL-2.0
  3
  4# Setup script for running ksft tests over a real interface in loopback mode.
  5# This scripts replaces the historical setup_loopback.sh. It puts
  6# a (presumably) real hardware interface into loopback mode, creates macvlan
  7# interfaces on top and places them in a network namespace for isolation.
  8#
  9# NETIF env variable must be exported to indicate the real target device.
 10# Note that the test will override NETIF with one of the macvlans, the
 11# actual ksft test will only see the macvlans.
 12#
 13# Example use:
 14#   export NETIF=eth0
 15#   ./net/lib/ksft_setup_loopback.sh ./drivers/net/gro.py
 16
 17if [ -z "$NETIF" ]; then
 18    echo "Error: NETIF variable not set"
 19    exit 1
 20fi
 21if ! [ -d "/sys/class/net/$NETIF" ]; then
 22    echo "Error: Can't find $NETIF, invalid netdevice"
 23    exit 1
 24fi
 25
 26# Save original settings for cleanup
 27readonly FLUSH_PATH="/sys/class/net/${NETIF}/gro_flush_timeout"
 28readonly IRQ_PATH="/sys/class/net/${NETIF}/napi_defer_hard_irqs"
 29FLUSH_TIMEOUT="$(< "${FLUSH_PATH}")"
 30readonly FLUSH_TIMEOUT
 31HARD_IRQS="$(< "${IRQ_PATH}")"
 32readonly HARD_IRQS
 33
 34SERVER_NS=$(mktemp -u server-XXXXXXXX)
 35readonly SERVER_NS
 36CLIENT_NS=$(mktemp -u client-XXXXXXXX)
 37readonly CLIENT_NS
 38readonly SERVER_MAC="aa:00:00:00:00:02"
 39readonly CLIENT_MAC="aa:00:00:00:00:01"
 40
 41# ksft expects addresses to communicate with remote
 42export  LOCAL_V6=2001:db8:1::1
 43export REMOTE_V6=2001:db8:1::2
 44
 45cleanup() {
 46    local exit_code=$?
 47
 48    echo "Cleaning up..."
 49
 50    # Remove macvlan interfaces and namespaces
 51    ip -netns "${SERVER_NS}" link del dev server 2>/dev/null || true
 52    ip netns del "${SERVER_NS}" 2>/dev/null || true
 53    ip -netns "${CLIENT_NS}" link del dev client 2>/dev/null || true
 54    ip netns del "${CLIENT_NS}" 2>/dev/null || true
 55
 56    # Disable loopback
 57    ethtool -K "${NETIF}" loopback off 2>/dev/null || true
 58    sleep 1
 59
 60    echo "${FLUSH_TIMEOUT}" >"${FLUSH_PATH}"
 61    echo "${HARD_IRQS}" >"${IRQ_PATH}"
 62
 63    exit $exit_code
 64}
 65
 66trap cleanup EXIT INT TERM
 67
 68# Enable loopback mode
 69echo "Enabling loopback on ${NETIF}..."
 70ethtool -K "${NETIF}" loopback on || {
 71    echo "Failed to enable loopback mode"
 72    exit 1
 73}
 74# The interface may need time to get carrier back, but selftests
 75# will wait for carrier, so no need to wait / sleep here.
 76
 77# Use timer on  host to trigger the network stack
 78# Also disable device interrupt to not depend on NIC interrupt
 79# Reduce test flakiness caused by unexpected interrupts
 80echo 100000 >"${FLUSH_PATH}"
 81echo 50 >"${IRQ_PATH}"
 82
 83# Create server namespace with macvlan
 84ip netns add "${SERVER_NS}"
 85ip link add link "${NETIF}" dev server address "${SERVER_MAC}" type macvlan
 86ip link set dev server netns "${SERVER_NS}"
 87ip -netns "${SERVER_NS}" link set dev server up
 88ip -netns "${SERVER_NS}" addr add $LOCAL_V6/64 dev server
 89ip -netns "${SERVER_NS}" link set dev lo up
 90
 91# Create client namespace with macvlan
 92ip netns add "${CLIENT_NS}"
 93ip link add link "${NETIF}" dev client address "${CLIENT_MAC}" type macvlan
 94ip link set dev client netns "${CLIENT_NS}"
 95ip -netns "${CLIENT_NS}" link set dev client up
 96ip -netns "${CLIENT_NS}" addr add $REMOTE_V6/64 dev client
 97ip -netns "${CLIENT_NS}" link set dev lo up
 98
 99echo "Setup complete!"
100echo "  Device: ${NETIF}"
101echo "  Server NS: ${SERVER_NS}"
102echo "  Client NS: ${CLIENT_NS}"
103echo ""
104
105# Setup environment variables for tests
106export NETIF=server
107export REMOTE_TYPE=netns
108export REMOTE_ARGS="${CLIENT_NS}"
109
110# Run the command
111ip netns exec "${SERVER_NS}" "$@"