selftests: forwarding: Remove duplicated lib.sh content

commit 25ae948b4478 ("selftests/net: add lib.sh") added net/lib.sh to
contain code shared by tests under net/ and net/forwarding/. However, this
caused issues with selftests from directories other than net/forwarding/,
in particular those under drivers/net/. Those issues were avoided in a
simple way by duplicating some content in commit 2114e83381d3 ("selftests:
forwarding: Avoid failures to source net/lib.sh").

In order to remove the duplicated content, restore the inclusion of
net/lib.sh from net/forwarding/lib.sh but with the following changes:

* net/lib.sh is imported through the net_forwarding_dir path
The original expression "source ../lib.sh" would look for lib.sh in the
directory above the script file's one, which did not work for tests under
drivers/net/.

* net/lib.sh is added to TEST_INCLUDES
Since net/forwarding/lib.sh now sources net/lib.sh, both of those files
must be exported along with tests which source net/forwarding/lib.sh.

Suggested-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: dsa: Replace test symlinks by wrapper script

The dsa tests which are symlinks of tests from net/forwarding/ (like
tc_actions.sh) become regular files after export (because `rsync
--copy-unsafe-links` is used) and expect to source lib.sh
(net/forwarding/lib.sh) from the same directory.

In the last patch of this series, net/forwarding/lib.sh will source lib.sh
from its parent directory (ie. net/lib.sh). This would not work for dsa
tests because net/lib.sh is not present under drivers/net/.

Since the tests in net/forwarding/ are not meant to be copied and run from
another directory, as a preparation for that last patch, replace the test
symlinks by a wrapper script which runs the original tests under
net/forwarding/. Following from that, the links to shared library scripts
in dsa/ are no longer used so remove them and add all the original files
needed from parent directories to TEST_INCLUDES.

Suggested-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: dsa: symlink the tc_actions.sh test

This has been validated on the Ocelot/Felix switch family (NXP LS1028A)
and should be relevant to any switch driver that offloads the tc-flower
and/or tc-matchall actions trap, drop, accept, mirred, for which DSA has
operations.

TEST: gact drop and ok (skip_hw) [ OK ]
TEST: mirred egress flower redirect (skip_hw) [ OK ]
TEST: mirred egress flower mirror (skip_hw) [ OK ]
TEST: mirred egress matchall mirror (skip_hw) [ OK ]
TEST: mirred_egress_to_ingress (skip_hw) [ OK ]
TEST: gact drop and ok (skip_sw) [ OK ]
TEST: mirred egress flower redirect (skip_sw) [ OK ]
TEST: mirred egress flower mirror (skip_sw) [ OK ]
TEST: mirred egress matchall mirror (skip_sw) [ OK ]
TEST: trap (skip_sw) [ OK ]
TEST: mirred_egress_to_ingress (skip_sw) [ OK ]

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220831170839.931184-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: net: dsa: Add a Makefile which installs the selftests

Add a Makefile which takes care of installing the selftests in
tools/testing/selftests/drivers/net/dsa. This can be used to install all
DSA specific selftests and forwarding.config using the same approach as
for the selftests in tools/testing/selftests/net/forwarding.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220727191642.480279-1-martin.blumenstingl@googlemail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>