devlink: Add packet traps for 802.1X operation

Add packet traps for 802.1X operation. The "eapol" control trap is used
to trap EAPOL packets and is required for the correct operation of the
control plane. The "locked_port" drop trap can be enabled to gain
visibility into packets that were dropped by the device due to the
locked bridge port check.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

documentation: networking: devlink: fix prestera.rst formatting that causes build warnings

Fixes: 66826c43e63d ("documentation: networking: devlink: add prestera switched driver Documentation")

Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

docs: networking: devlink: avoid using ReST :doc:`foo` markup

The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/4553858bc9a5442eba6d71caff8047e84ece4d9b.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

devlink: Add DMAC filter generic packet trap

Add packet trap that can report packets that were dropped due to
destination MAC filtering.

Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

devlink: Add blackhole_nexthop trap

Add a packet trap to report packets that were dropped due to a
blackhole nexthop.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

devlink: add parser error drop packet traps

Add parser error drop packet traps, so that capable device driver could
register them with devlink. The new packet trap group holds any drops of
packets which were marked by the device as erroneous during header
parsing. Add documentation for every added packet trap and packet trap
group.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

devlink: Add early_drop trap

Add the packet trap that can report packets that were ECN marked due to RED
AQM.

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

mlxsw: spectrum: Use different trap group for externally routed packets

Cited commit mistakenly removed the trap group for externally routed
packets (e.g., via the management interface) and grouped locally routed
and externally routed packet traps under the same group, thereby
subjecting them to the same policer.

This can result in problems, for example, when FRR is restarted and
suddenly all transient traffic is trapped to the CPU because of a
default route through the management interface. Locally routed packets
required to re-establish a BGP connection will never reach the CPU and
the routing tables will not be re-populated.

Fix this by using a different trap group for externally routed packets.

Fixes: 8110668ecd9a ("mlxsw: spectrum_trap: Register layer 3 control traps")
Reported-by: Alex Veber <alexve@mellanox.com>
Tested-by: Alex Veber <alexve@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>

devlink: Add ACL control packet traps

Add packet traps for packets that are sampled / trapped by ACLs, so that
capable drivers could register them with devlink. Add documentation for
every added packet trap and packet trap group.

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

devlink: Add layer 3 control packet traps

Add layer 3 control packet traps such as ARP and DHCP, so that capable
device drivers could register them with devlink. Add documentation for
every added packet trap and packet trap group.

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

devlink: Add layer 2 control packet traps

Add layer 2 control packet traps such as STP and IGMP query, so that
capable device drivers could register them with devlink. Add
documentation for every added packet trap and packet trap group.

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

devlink: Add 'control' trap type

This type is used for traps that trap control packets such as ARP
request and IGMP query to the CPU.

Do not report such packets to the kernel's drop monitor as they were not
dropped by the device no encountered an exception during forwarding.

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

devlink: Add 'mirror' trap action

The action is used by control traps such as IGMP query. The packet is
flooded by the device, but also trapped to the CPU in order for the
software bridge to mark the receiving port as a multicast router port.
Such packets are marked with 'skb->offload_fwd_mark = 1' in order to
prevent the software bridge from flooding them again.

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

devlink: Create dedicated trap group for layer 3 exceptions

Packets that hit exceptions during layer 3 forwarding must be trapped to
the CPU for the control plane to function properly. Create a dedicated
group for them, so that user space could choose to assign a different
policer for them.

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

Documentation: devlink: fix broken link warning

At 'make htmldocs' the following warning is thrown:

Documentation/networking/devlink/devlink-trap.rst:302:
WARNING: undefined label: generic-packet-trap-groups

Fixes the warning by setting the label to the specified header,
within the same document.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation: Add description of packet trap policers

Extend devlink-trap documentation with information about packet trap
policers.

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

devlink: add ACL generic packet traps

Add packet traps that can report packets that were dropped during ACL
processing.

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

devlink: Add overlay source MAC is multicast trap

Add packet trap that can report NVE packets that the device decided to
drop because their overlay source MAC is multicast.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

devlink: Add tunnel generic packet traps

Add packet traps that can report packets that were dropped during tunnel
decapsulation.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

devlink: Add non-routable packet trap

Add packet trap that can report packets that reached the router, but are
non-routable. For example, IGMP queries can be flooded by the device in
layer 2 and reach the router. Such packets should not be routed and
instead dropped.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Add irif and erif disabled traps

IRIF_DISABLED and ERIF_DISABLED are driver specific traps. Packets are
dropped for these reasons when they need to be routed through/from
existing router interfaces (RIF) which are disabled.

Add devlink driver-specific traps and mlxsw trap IDs used to report
these traps.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

devlink: rename and expand devlink-trap-netdevsim.rst

Rename the trap-specific netdevimsim.rst file, and expand it to include
documentation of all the devlink features currently implemented by the
netdevsim driver code.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

devlink: move devlink documentation to subfolder

Combine the documentation for devlink into a subfolder, and provide an
index.rst file that can be used to generally describe devlink.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>