Before this change, four related - but distinct - concepts where named
offload_fwd_mark:

- skb->offload_fwd_mark: Set by the switchdev driver if the underlying
  hardware has already forwarded this frame to the other ports in the
  same hardware domain.

- nbp->offload_fwd_mark: An idetifier used to group ports that share
  the same hardware forwarding domain.

- br->offload_fwd_mark: Counter used to make sure that unique IDs are
  used in cases where a bridge contains ports from multiple hardware
  domains.

- skb->cb->offload_fwd_mark: The hardware domain on which the frame
  ingressed and was forwarded.

Introduce the term "hardware forwarding domain" ("hwdom") in the
bridge to denote a set of ports with the following property:

    If an skb with skb->offload_fwd_mark set, is received on a port
    belonging to hwdom N, that frame has already been forwarded to all
    other ports in hwdom N.

By decoupling the name from "offload_fwd_mark", we can extend the
term's definition in the future - e.g. to add constraints that
describe expected egress behavior - without overloading the meaning of
"offload_fwd_mark".

- nbp->offload_fwd_mark thus becomes nbp->hwdom.

- br->offload_fwd_mark becomes br->last_hwdom.

- skb->cb->offload_fwd_mark becomes skb->cb->src_hwdom. The slight
  change in naming here mandates a slight change in behavior of the
  nbp_switchdev_frame_mark() function. Previously, it only set this
  value in skb->cb for packets with skb->offload_fwd_mark true (ones
  which were forwarded in hardware). Whereas now we always track the
  incoming hwdom for all packets coming from a switchdev (even for the
  packets which weren't forwarded in hardware, such as STP BPDUs, IGMP
  reports etc). As all uses of skb->cb->offload_fwd_mark were already
  gated behind checks of skb->offload_fwd_mark, this will not introduce
  any functional change, but it paves the way for future changes where
  the ingressing hwdom must be known for frames coming from a switchdev
  regardless of whether they were forwarded in hardware or not
  (basically, if the skb comes from a switchdev, skb->cb->src_hwdom now
  always tracks which one).

  A typical example where this is relevant: the switchdev has a fixed
  configuration to trap STP BPDUs, but STP is not running on the bridge
  and the group_fwd_mask allows them to be forwarded. Say we have this
  setup:

        br0
       / | \
      /  |  \
  swp0 swp1 swp2

  A BPDU comes in on swp0 and is trapped to the CPU; the driver does not
  set skb->offload_fwd_mark. The bridge determines that the frame should
  be forwarded to swp{1,2}. It is imperative that forward offloading is
  _not_ allowed in this case, as the source hwdom is already "poisoned".

  Recording the source hwdom allows this case to be handled properly.

v2->v3: added code comments
v3->v6: none
Signed-off-by: NTobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adding bridge multicast context support for host-joined groups is easy
because we only need the proper timer value. We pass the already chosen
context and use its timer value.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Choose the proper bridge multicast context when user-spaces is adding
mdb entries. Currently we require the vlan to be configured on at least
one device (port or bridge) in order to add an mdb entry if vlan
mcast snooping is enabled (vlan snooping implies vlan filtering).
Note that we always allow deleting an entry, regardless of the vlan state.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the recent change to use bridge/port multicast context pointers
instead of bridge/port I missed to convert two locations which pass the
port pointer as-is, but with the new model we need to verify the port
context is non-NULL first and retrieve the port from it. The first
location is when doing querier selection when a query is received, the
second location is when leaving a group. The port context will be null
if the packets originated from the bridge device (i.e. from the host).
The fix is simple just check if the port context exists and retrieve
the port pointer from it.

Fixes: adc47037 ("net: bridge: multicast: use multicast contexts instead of bridge or port")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a new global vlan option which controls whether multicast snooping
is enabled or disabled for a single vlan. It controls the vlan private
flag: BR_VLFLAG_GLOBAL_MCAST_ENABLED.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for global options notifications. They use only RTM_NEWVLAN
since global options can only be set and are contained in a separate
vlan global options attribute. Notifications are compressed in ranges
where possible, i.e. the sequential vlan options are equal.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a new vlan options dump flag which causes only global vlan options
to be dumped. The dumps are done only with bridge devices, ports are
ignored. They support vlan compression if the options in sequential
vlans are equal (currently always true).
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can have two types of vlan options depending on context:
 - per-device vlan options (split in per-bridge and per-port)
 - global vlan options

The second type wasn't supported in the bridge until now, but we need
them for per-vlan multicast support, per-vlan STP support and other
options which require global vlan context. They are contained in the global
bridge vlan context even if the vlan is not configured on the bridge device
itself. This patch adds initial netlink attributes and support for setting
these global vlan options, they can only be set (RTM_NEWVLAN) and the
operation must use the bridge device. Since there are no such options yet
it shouldn't have any functional effect.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the port multicast context to check if the router port is a vlan and
in case it is include its vlan id in the notification.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add basic vlan context querier support, if the contexts passed to
multicast_alloc_query are vlan then the query will be tagged. Also
handle querier start/stop of vlan contexts.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add helpers which check if the current bridge/port multicast context
should be used (i.e. they're not disabled) and use them for Rx IGMP/MLD
processing, timers and new group addition. It is important for vlans to
disable processing of timer/packet after the multicast_lock is obtained
if the vlan context doesn't have BR_VLFLAG_MCAST_ENABLED. There are two
cases when that flag is missing:
 - if the vlan is getting destroyed it will be removed and timers will
   be stopped
 - if the vlan mcast snooping is being disabled
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to use the new port group to port context helper in places where
we cannot pass down the proper context (i.e. functions that can be
called by timers or outside the packet snooping paths).
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add br_multicast_pg_to_port_ctx() which returns the proper port multicast
context from either port or vlan based on bridge option and vlan flags.
As the comment inside explains the locking is a bit tricky, we rely on
the fact that BR_VLFLAG_MCAST_ENABLED requires multicast_lock to change
and we also require it to be held to call that helper. If we find the
vlan under rcu and it still has the flag then we can be sure it will be
alive until we unlock multicast_lock which should be enough.
Note that the context might change from vlan to bridge between different
calls to this helper as the mcast vlan knob requires only rtnl so it should
be used carefully and for read-only/check purposes.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a global knob that controls if vlan multicast snooping is enabled.
The proper contexts (vlan or bridge-wide) will be chosen based on the knob
when processing packets and changing bridge device state. Note that
vlans have their individual mcast snooping enabled by default, but this
knob is needed to turn on bridge vlan snooping. It is disabled by
default. To enable the knob vlan filtering must also be enabled, it
doesn't make sense to have vlan mcast snooping without vlan filtering
since that would lead to inconsistencies. Disabling vlan filtering will
also automatically disable vlan mcast snooping.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add helpers to enable/disable vlan multicast based on its flags, we need
two flags because we need to know if the vlan has multicast enabled
globally (user-controlled) and if it has it enabled on the specific device
(bridge or port). The new private vlan flags are:
 - BR_VLFLAG_MCAST_ENABLED: locally enabled multicast on the device, used
   when removing a vlan, toggling vlan mcast snooping and controlling
   single vlan (kernel-controlled, valid under RTNL and multicast_lock)
 - BR_VLFLAG_GLOBAL_MCAST_ENABLED: globally enabled multicast for the
   vlan, used to control the bridge-wide vlan mcast snooping for a
   single vlan (user-controlled, can be checked under any context)

Bridge vlan contexts are created with multicast snooping enabled by
default to be in line with the current bridge snooping defaults. In
order to actually activate per vlan snooping and context usage a
bridge-wide knob will be added later which will default to disabled.
If that knob is enabled then automatically all vlan snooping will be
enabled. All vlan contexts are initialized with the current bridge
multicast context defaults.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add global and per-port vlan multicast context, only initialized but
still not used. No functional changes intended.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid 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: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Factor out the bridge's global multicast context into a separate
structure which will later be used for per-vlan global context.
No functional changes intended.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Factor out the port's multicast context into a separate structure which
will later be shared for per-port,vlan context. No functional changes
intended. We need the structure even if bridge multicast is not defined
to pass down as pointer to forwarding functions.
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When an MRD advertisement is received on a bridge port with multicast
snooping enabled, we mark it as a router port automatically, that
includes adding that port to the router port list. The multicast lock
protects that list, but it is not acquired in the MRD advertisement case
leading to a race condition, we need to take it to fix the race.

Cc: stable@vger.kernel.org
Cc: linus.luessing@c0d3.blue
Fixes: 4b3087c7 ("bridge: Snoop Multicast Router Advertisements")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a PIM hello packet is received on a bridge port with multicast
snooping enabled, we mark it as a router port automatically, that
includes adding that port the router port list. The multicast lock
protects that list, but it is not acquired in the PIM message case
leading to a race condition, we need to take it to fix the race.

Cc: stable@vger.kernel.org
Fixes: 91b02d3d ("bridge: mcast: add router port on PIM hello message")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 2796d0c6 ("bridge: Automatically manage
port promiscuous mode.")
bridges with `vlan_filtering 1` and only 1 auto-port don't
set IFF_PROMISC for unicast-filtering-capable ports.

Normally on port changes `br_manage_promisc` is called to
update the promisc flags and unicast filters if necessary,
but it cannot distinguish between *new* ports and ones
losing their promisc flag, and new ports end up not
receiving the MAC address list.

Fix this by calling `br_fdb_sync_static` in `br_add_if`
after the port promisc flags are updated and the unicast
filter was supposed to have been filled.

Fixes: 2796d0c6 ("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: NWolfgang Bumiller <w.bumiller@proxmox.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a port joins a bridge which already has local FDB entries pointing
to the bridge device itself, we would like to offload those, so allow
the "dev" argument to be equal to the bridge too. The code already does
what we need in that case.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Treat addresses added to the bridge itself in the same way as regular
ports and send out a notification so that drivers may sync it down to
the hardware FDB.
Signed-off-by: NTobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Annotate the writer side of fdb->dst:

- fdb_create()
- br_fdb_update()
- fdb_add_entry()
- br_fdb_external_learn_add()

with WRITE_ONCE() and the reader side:

- br_fdb_test_addr()
- br_fdb_update()
- fdb_fill_info()
- fdb_add_entry()
- fdb_delete_by_addr_and_port()
- br_fdb_external_learn_add()
- br_switchdev_fdb_notify()

with compiler barriers such that the readers do not attempt to reload
fdb->dst multiple times, leading to potentially different destination
ports when the fdb entry is updated concurrently.

This is especially important in read-side sections where fdb->dst is
used more than once, but let's convert all accesses for the sake of
uniformity.
Suggested-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to the standard IEC 62439-2, in case the node behaves as MRA
and needs to send Test frames on ring ports, then these Test frames need
to have an Option TLV and a Sub-Option TLV which has the type AUTO_MGR.
Signed-off-by: NHoratiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a switchdev port leaves a LAG that is a bridge port, the switchdev
objects and port attributes offloaded to that port are not removed:

ip link add br0 type bridge
ip link add bond0 type bond mode 802.3ad
ip link set swp0 master bond0
ip link set bond0 master br0
bridge vlan add dev bond0 vid 100
ip link set swp0 nomaster

VLAN 100 will remain installed on swp0 despite it going into standalone
mode, because as far as the bridge is concerned, nothing ever happened
to its bridge port.

Let's extend the bridge vlan, fdb and mdb replay functions to take a
'bool adding' argument, and make DSA and ocelot call the replay
functions with 'adding' as false from the switchdev unsync path, for the
switch port that leaves the bridge.

Note that this patch in itself does not salvage anything, because in the
current pull mode of operation, DSA still needs to call the replay
helpers with adding=false. This will be done in another patch.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some of the arguments and local variables for the newly added switchdev
replay helpers can be const, so let's make them so.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a slight inconvenience in the switchdev replay helpers added
recently, and this is when:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set bond0 master br0
bridge vlan add dev bond0 vid 100
ip link set swp0 master bond0
ip link set swp1 master bond0

Since the underlying driver (currently only DSA) asks for a replay of
VLANs when swp0 and swp1 join the LAG because it is bridged, what will
happen is that DSA will try to react twice on the VLAN event for swp0.
This is not really a huge problem right now, because most drivers accept
duplicates since the bridge itself does, but it will become a problem
when we add support for replaying switchdev object deletions.

Let's fix this by adding a blank void *ctx in the replay helpers, which
will be passed on by the bridge in the switchdev notifications. If the
context is NULL, everything is the same as before. But if the context is
populated with a valid pointer, the underlying switchdev driver
(currently DSA) can use the pointer to 'see through' the bridge port
(which in the example above is bond0) and 'know' that the event is only
for a particular physical port offloading that bridge port, and not for
all of them.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 2c4eca3e ("net: bridge: switchdev: include local flag
in FDB notifications"), the bridge emits SWITCHDEV_FDB_ADD_TO_DEVICE
events with the is_local flag populated (but we ignore it nonetheless).

We would like DSA to start treating this bit, but it is still not
populated by the replay helper, so add it there too.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Return statements are not needed in Void function.
Signed-off-by: Ngushengxian <gushengxian@yulong.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The continue statement at the end of a for-loop has no effect,
invert the if expression and remove the continue.

Addresses-Coverity: ("Continue has no effect")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The egress tunnel code uses dst_clone() and directly sets the result
which is wrong because the entry might have 0 refcnt or be already deleted,
causing number of problems. It also triggers the WARN_ON() in dst_hold()[1]
when a refcnt couldn't be taken. Fix it by using dst_hold_safe() and
checking if a reference was actually taken before setting the dst.

[1] dmesg WARN_ON log and following refcnt errors
 WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net
 CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G        W         5.13.0-rc3+ #360
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49
 RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0
 RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001
 R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000
 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401
 FS:  0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0
 Call Trace:
  br_handle_vlan+0xbc/0xca [bridge]
  __br_forward+0x23/0x164 [bridge]
  deliver_clone+0x41/0x48 [bridge]
  br_handle_frame_finish+0x36f/0x3aa [bridge]
  ? skb_dst+0x2e/0x38 [bridge]
  ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge]
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  br_handle_frame+0x2c3/0x377 [bridge]
  ? __skb_pull+0x33/0x51
  ? vlan_do_receive+0x4f/0x36a
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  __netif_receive_skb_core+0x539/0x7c6
  ? __list_del_entry_valid+0x16e/0x1c2
  __netif_receive_skb_list_core+0x6d/0xd6
  netif_receive_skb_list_internal+0x1d9/0x1fa
  gro_normal_list+0x22/0x3e
  dev_gro_receive+0x55b/0x600
  ? detach_buf_split+0x58/0x140
  napi_gro_receive+0x94/0x12e
  virtnet_poll+0x15d/0x315 [virtio_net]
  __napi_poll+0x2c/0x1c9
  net_rx_action+0xe6/0x1fb
  __do_softirq+0x115/0x2d8
  run_ksoftirqd+0x18/0x20
  smpboot_thread_fn+0x183/0x19c
  ? smpboot_unregister_percpu_thread+0x66/0x66
  kthread+0x10a/0x10f
  ? kthread_mod_delayed_work+0xb6/0xb6
  ret_from_fork+0x22/0x30
 ---[ end trace 49f61b07f775fd2b ]---
 dst_release: dst:00000000c02d677a refcnt:-1
 dst_release underflow

Cc: stable@vger.kernel.org
Fixes: 11538d03 ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a tunnel_dst null pointer dereference due to lockless
access in the tunnel egress path. When deleting a vlan tunnel the
tunnel_dst pointer is set to NULL without waiting a grace period (i.e.
while it's still usable) and packets egressing are dereferencing it
without checking. Use READ/WRITE_ONCE to annotate the lockless use of
tunnel_id, use RCU for accessing tunnel_dst and make sure it is read
only once and checked in the egress path. The dst is already properly RCU
protected so we don't need to do anything fancy than to make sure
tunnel_id and tunnel_dst are read only once and checked in the egress path.

Cc: stable@vger.kernel.org
Fixes: 11538d03 ("bridge: vlan dst_metadata hooks in ingress and egress paths")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to the standard IEC 62439-2, the number of transitions needs
to be counted for each transition 'between' ring state open and ring
state closed and not from open state to closed state.

Therefore fix this for both ring and interconnect ring.
Signed-off-by: NHoratiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The variable br is assigned a value that is not being read after
exiting case IFLA_STATS_LINK_XSTATS_SLAVE. The assignment is
redundant and can be removed.

Addresses-Coverity ("Unused value")
Signed-off-by: NNigel Christian <nigel.l.christian@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The br_ip6_multicast_add_router() prototype is defined only when
CONFIG_IPV6 is enabled, but the function is always referenced, so there
is this build error with CONFIG_IPV6 not defined:

net/bridge/br_multicast.c: In function ‘__br_multicast_enable_port’:
net/bridge/br_multicast.c:1743:3: error: implicit declaration of function ‘br_ip6_multicast_add_router’; did you mean ‘br_ip4_multicast_add_router’? [-Werror=implicit-function-declaration]
 1743 |   br_ip6_multicast_add_router(br, port);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~
      |   br_ip4_multicast_add_router
net/bridge/br_multicast.c: At top level:
net/bridge/br_multicast.c:2804:13: warning: conflicting types for ‘br_ip6_multicast_add_router’
 2804 | static void br_ip6_multicast_add_router(struct net_bridge *br,
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~
net/bridge/br_multicast.c:2804:13: error: static declaration of ‘br_ip6_multicast_add_router’ follows non-static declaration
net/bridge/br_multicast.c:1743:3: note: previous implicit declaration of ‘br_ip6_multicast_add_router’ was here
 1743 |   br_ip6_multicast_add_router(br, port);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~

Fix this build error by moving the definition out of the #ifdef.

Fixes: a3c02e76 ("net: bridge: mcast: split multicast router state for IPv4 and IPv6")
Signed-off-by: NMatteo Croce <mcroce@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

br_multicast_is_router takes two arguments when bridge IGMP is enabled
and just one when it's disabled, fix the stub to take two as well.

Fixes: 1a3065a2 ("net: bridge: mcast: prepare is-router function for mcast router split")
Signed-off-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To properly support routable multicast addresses in batman-adv in a
group-aware way, a batman-adv node needs to know if it serves multicast
routers.

This adds a function to the bridge to export this so that batman-adv
can then make full use of the Multicast Router Discovery capability of
the bridge.
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have split the multicast router state into two, one for IPv4
and one for IPv6, also add individual timers to the mdb netlink router
port dump. Leaving the old timer attribute for backwards compatibility.
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>