Jiri Pirko says:
====================
mlxsw: Enable VRF offload
Ido says:
Packets received from netdevs enslaved to different VRF devices are
forwarded using different FIB tables. In the Spectrum ASIC this is
achieved by binding different router interfaces (RIFs) to different
virtual routers (VRs). Each RIF represents an enslaved netdev and each
VR has its own FIB table according to which packets are forwarded.
The first three patches add an helper to check if a FIB rule is a
default rule and extend the FIB notification chain to include the rule's
info as part of the RULE_{ADD,DEL} events. This allows offloading
drivers to sanitize the rules they don't support and flush their tables.
The fourth patch introduces a small change in the VRF driver to allow
capable drivers to more easily offload VRFs.
Finally, the last patches gradually add support for VRFs in the mlxsw
driver. First, on top of port netdevs, stacked LAG and VLAN devices and
then on top of bridges.
Some limitations I would like to point out:
1) The old model where 'oif' / 'iif' rules were programmed for each L3
master device isn't supported. Upon insertion of these rules the driver
will flush its tables and forwarding will be done by the kernel instead.
It's inferior in every way to the single 'l3mdev' rule, so this shouldn't
be an issue.
2) Inter-VRF routes pointing to a VRF device aren't offloaded. Packets
hitting these routes will be forwarded by the kernel. Inter-VRF routes
pointing to netdevs enslaved to a different VRF are offloaded.
3) There's a small discrepancy between the kernel's datapath and the
device's. By default, packets forwarded by the kernel first do a lookup
in the local table and then in the VRF's table (assuming no match). In
the device, lookup is done only in the VRF's table, which is probably
the intended behavior. Changes in v2 allow user to properly re-order the
default rules without triggering the abort mechanism.
Changes in v3:
* Remove 'l3mdev' from the matchall list, as it's related to the action
and not the selector (David Ahern).
* Use container_of() instead of typecasting (David Ahern).
* Add David's Acked-by to the second patch.
* Add an helper in IPv4 code to check if rule is a default rule (David
Ahern).
Changes in v2:
* Drop default rule indication and allow re-ordering of default rules
(David Ahern).
* Remove ifdef around 'struct fib_rule_notifier_info' and drop redundant
dependency on IP_MULTIPLE_TABLES from rocker and mlxsw.
* Add David's Acked-by to the fourth patch.
* Remove netif_is_vrf_master() and use netif_is_l3_master() instead
(David Ahern).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>