Right now, skb->tstamp is reset to 0 whenever the skb is forwarded.

If skb->tstamp has the mono delivery_time, clearing it can hurt
the performance when it finally transmits out to fq@phy-dev.

The earlier patch added a skb->mono_delivery_time bit to
flag the skb->tstamp carrying the mono delivery_time.

This patch adds skb_clear_tstamp() helper which keeps
the mono delivery_time and clears everything else.

The delivery_time clearing will be postponed until the stack knows the
skb will be delivered locally.  It will be done in a latter patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Switchdev support can be disabled at compile time, and in that case,
struct sk_buff will not contain the offload_fwd_mark field.

To make the code in br_forward.c work in both cases, we do what is done
in other places and we create a helper function, with an empty shim
definition, that is implemented by the br_switchdev.o translation module.
This is always compiled if and only if CONFIG_NET_SWITCHDEV is y or m.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 472111920f1c ("net: bridge: switchdev: allow the TX data plane forwarding to be offloaded")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Allow switchdevs to forward frames from the CPU in accordance with the
bridge configuration in the same way as is done between bridge
ports. This means that the bridge will only send a single skb towards
one of the ports under the switchdev's control, and expects the driver
to deliver the packet to all eligible ports in its domain.

Primarily this improves the performance of multicast flows with
multiple subscribers, as it allows the hardware to perform the frame
replication.

The basic flow between the driver and the bridge is as follows:

- When joining a bridge port, the switchdev driver calls
  switchdev_bridge_port_offload() with tx_fwd_offload = true.

- The bridge sends offloadable skbs to one of the ports under the
  switchdev's control using skb->offload_fwd_mark = true.

- The switchdev driver checks the skb->offload_fwd_mark field and lets
  its FDB lookup select the destination port mask for this packet.

v1->v2:
- convert br_input_skb_cb::fwd_hwdoms to a plain unsigned long
- introduce a static key "br_switchdev_fwd_offload_used" to minimize the
  impact of the newly introduced feature on all the setups which don't
  have hardware that can make use of it
- introduce a check for nbp->flags & BR_FWD_OFFLOAD to optimize cache
  line access
- reorder nbp_switchdev_frame_mark_accel() and br_handle_vlan() in
  __br_forward()
- do not strip VLAN on egress if forwarding offload on VLAN-aware bridge
  is being used
- propagate errors from .ndo_dfwd_add_station() if not EOPNOTSUPP

v2->v3:
- replace the solution based on .ndo_dfwd_add_station with a solution
  based on switchdev_bridge_port_offload
- rename BR_FWD_OFFLOAD to BR_TX_FWD_OFFLOAD
v3->v4: rebase
v4->v5:
- make sure the static key is decremented on bridge port unoffload
- more function and variable renaming and comments for them:
  br_switchdev_fwd_offload_used to br_switchdev_tx_fwd_offload
  br_switchdev_accels_skb to br_switchdev_frame_uses_tx_fwd_offload
  nbp_switchdev_frame_mark_tx_fwd to nbp_switchdev_frame_mark_tx_fwd_to_hwdom
  nbp_switchdev_frame_mark_accel to nbp_switchdev_frame_mark_tx_fwd_offload
  fwd_accel to tx_fwd_offload

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pass multicast context pointers to multicast functions instead of bridge/port.
This would make it easier later to switch these contexts to their per-vlan
versions. The patch is basically search and replace, no functional changes.

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants and to avoid IPv6 #ifdef clutter later add
two wrapper functions for router node retrieval in the payload
forwarding code.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants, rename the affected variable to the IPv4
version first to avoid some renames in later commits.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace some checks for ETH_P_8021Q and ETH_P_8021AD with
eth_type_vlan().

Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/20210117080950.122761-1-dong.menglong@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

We need to avoid forwarding to ports in MCAST_INCLUDE filter mode when the
mdst entry is a *,G or when the port has the blocked flag.

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

To speedup S,G forward handling we need to be able to quickly find out
if a port is a member of an S,G group. To do that add a global S,G port
rhashtable with key: source addr, group addr, protocol, vid (all br_ip
fields) and port pointer.

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If we make sure that br_allowed_egress is called only when we have
BR_STATE_FORWARDING state then we can avoid a test later when we add
per-vlan state.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>