linux/include
Vladimir Oltean ec638740fc net: switchdev: remove lag_mod_cb from switchdev_handle_fdb_event_to_device
When the switchdev_handle_fdb_event_to_device() event replication helper
was created, my original thought was that FDB events on LAG interfaces
should most likely be special-cased, not just replicated towards all
switchdev ports beneath that LAG. So this replication helper currently
does not recurse through switchdev lower interfaces of LAG bridge ports,
but rather calls the lag_mod_cb() if that was provided.

No switchdev driver uses this helper for FDB events on LAG interfaces
yet, so that was an assumption which was yet to be tested. It is
certainly usable for that purpose, as my RFC series shows:

https://patchwork.kernel.org/project/netdevbpf/cover/20220210125201.2859463-1-vladimir.oltean@nxp.com/

however this approach is slightly convoluted because:

- the switchdev driver gets a "dev" that isn't its own net device, but
  rather the LAG net device. It must call switchdev_lower_dev_find(dev)
  in order to get a handle of any of its own net devices (the ones that
  pass check_cb).

- in order for FDB entries on LAG ports to be correctly refcounted per
  the number of switchdev ports beneath that LAG, we haven't escaped the
  need to iterate through the LAG's lower interfaces. Except that is now
  the responsibility of the switchdev driver, because the replication
  helper just stopped half-way.

So, even though yes, FDB events on LAG bridge ports must be
special-cased, in the end it's simpler to let switchdev_handle_fdb_*
just iterate through the LAG port's switchdev lowers, and let the
switchdev driver figure out that those physical ports are under a LAG.

The switchdev_handle_fdb_event_to_device() helper takes a
"foreign_dev_check" callback so it can figure out whether @dev can
autonomously forward to @foreign_dev. DSA fills this method properly:
if the LAG is offloaded by another port in the same tree as @dev, then
it isn't foreign. If it is a software LAG, it is foreign - forwarding
happens in software.

Whether an interface is foreign or not decides whether the replication
helper will go through the LAG's switchdev lowers or not. Since the
lan966x doesn't properly fill this out, FDB events on software LAG
uppers will get called. By changing lan966x_foreign_dev_check(), we can
suppress them.

Whereas DSA will now start receiving FDB events for its offloaded LAG
uppers, so we need to return -EOPNOTSUPP, since we currently don't do
the right thing for them.

Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24 21:31:43 -08:00
..
acpi USB/Thunderbolt changes for 5.17-rc1 2022-01-12 11:27:57 -08:00
asm-generic bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
clocksource
crypto lib/crypto: blake2s: avoid indirect calls to compression function for Clang CFI 2022-02-04 19:22:32 +01:00
drm
dt-bindings Fixes for omaps 2022-02-07 17:42:44 +01:00
keys keys: X.509 public key issuer lookup without AKID 2022-01-09 00:18:42 +02:00
kunit kunit: replace kernel.h with the necessary inclusions 2022-01-20 08:52:54 +02:00
kvm RISCV: 2022-01-16 16:15:14 +02:00
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-02-24 17:54:25 -08:00
math-emu
media
memory
misc
net net: switchdev: remove lag_mod_cb from switchdev_handle_fdb_event_to_device 2022-02-24 21:31:43 -08:00
pcmcia
ras mm/hwpoison: remove MF_MSG_BUDDY_2ND and MF_MSG_POISONED_HUGE 2022-01-15 16:30:31 +02:00
rdma RDMA/core: Calculate UDP source port based on flow label or lqpn/rqpn 2022-01-07 19:34:01 -04:00
scsi Merge branch 'akpm' (patches from Andrew) 2022-01-22 11:28:23 +02:00
soc net: dsa: felix: update destinations of existing traps with ocelot-8021q 2022-02-17 14:06:51 +00:00
sound ASoC: Fixes for v5.17 2022-02-01 16:52:54 +01:00
target
trace net: tcp: use tcp_drop_reason() for tcp_data_queue_ofo() 2022-02-20 13:55:31 +00:00
uapi ethtool: add support to set/get completion queue event size 2022-02-23 20:33:05 -08:00
vdso
video
xen xen: xenbus_dev.h: delete incorrect file name 2022-02-03 08:16:32 +01:00