selftests: drivers: dsa: add a subset of forwarding selftests

This adds an initial subset of forwarding selftests which I considered
to be relevant for DSA drivers, along with a forwarding.config that
makes it easier to run them (disables veth pair creation, makes sure MAC
addresses are unique and stable).

The intention is to request driver writers to run these selftests during
review and make sure that the tests pass, or at least that the problems
are known.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: bridge: Parameterize ageing timeout

Allow the ageing timeout that is set on bridges to be customized from
forwarding.config. This allows the tests to be run on hardware which
does not support a 10s timeout (e.g. mv88e6xxx).

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: forwarding: Allow running specific tests

Similar to commit a511858c7536 ("selftests: fib_tests: Allow user to run
a specific test"), allow user to run only a subset of the tests using
the TESTS environment variable.

This is useful when not all the tests can pass on a given system.

Example:
# export TESTS="ping_ipv4 ping_ipv6"
# ./bridge_vlan_aware.sh
TEST: ping [PASS]
TEST: ping6 [PASS]

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: forwarding: Add a test for VLAN-unaware bridge

Similar to the VLAN-aware bridge test, test the VLAN-unaware bridge and
make sure that ping, FDB learning and flooding work as expected.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>