A node that has the MRA role, it can behave as MRM or MRC.

Initially it starts as MRM and sends MRP_Test frames on both ring ports.
If it detects that there are MRP_Test send by another MRM, then it
checks if these frames have a lower priority than itself. In this case
it would send MRP_Nack frames to notify the other node that it needs to
stop sending MRP_Test frames.
If it receives a MRP_Nack frame then it stops sending MRP_Test frames
and starts to behave as a MRC but it would continue to monitor the
MRP_Test frames send by MRM. If at a point the MRM stops to send
MRP_Test frames it would get the MRM role and start to send MRP_Test
frames.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Each MRP instance has a priority, a lower value means a higher priority.
The priority of MRP instance is stored in MRP_Test frame in this way
all the MRP nodes in the ring can see other nodes priority.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch reworks the MRP netlink interface. Before, each attribute
represented a binary structure which made it hard to be extended.
Therefore update the MRP netlink interface such that each existing
attribute to be a nested attribute which contains the fields of the
binary structures.
In this way the MRP netlink interface can be extended without breaking
the backwards compatibility. It is also using strict checking for
attributes under the MRP top attribute.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add new nested netlink attribute to configure the MRP. These attributes are used
by the userspace to add/delete/configure MRP instances and by the kernel to
notify the userspace when the MRP ring gets open/closed. MRP nested attribute
has the following attributes:

IFLA_BRIDGE_MRP_INSTANCE - the parameter type is br_mrp_instance which contains
  the instance id, and the ifindex of the two ports. The ports can't be part of
  multiple instances. This is used to create/delete MRP instances.

IFLA_BRIDGE_MRP_PORT_STATE - the parameter type is u32. Which can be forwarding,
  blocking or disabled.

IFLA_BRIDGE_MRP_PORT_ROLE - the parameter type is br_mrp_port_role which
  contains the instance id and the role. The role can be primary or secondary.

IFLA_BRIDGE_MRP_RING_STATE - the parameter type is br_mrp_ring_state which
  contains the instance id and the state. The state can be open or closed.

IFLA_BRIDGE_MRP_RING_ROLE - the parameter type is br_mrp_ring_role which
  contains the instance id and the ring role. The role can be MRM or MRC.

IFLA_BRIDGE_MRP_START_TEST - the parameter type is br_mrp_start_test which
  contains the instance id, the interval at which to send the MRP_Test frames,
  how many test frames can be missed before declaring the ring open and the
  period which represent for how long to send the test frames.

Also add the file include/uapi/linux/mrp_bridge.h which defines all the types
used by MRP that are also needed by the userpace.

Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that we have a nested tunnel info attribute we can add a separate
one for the tunnel command and require it explicitly from user-space. It
must be one of RTM_SETLINK/DELLINK. Only RTM_SETLINK requires a valid
tunnel id, DELLINK just removes it if it was set before. This allows us
to have all tunnel attributes and control in one place, thus removing
the need for an outside vlan info flag.

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

While discussing the new API, Roopa mentioned that we'll be adding more
tunnel attributes and options in the future, so it's better to make it a
nested attribute, since this is still in net-next we can easily change it
and nest the tunnel id attribute under BRIDGE_VLANDB_ENTRY_TUNNEL_INFO.

The new format is:
 [BRIDGE_VLANDB_ENTRY]
     [BRIDGE_VLANDB_ENTRY_TUNNEL_INFO]
         [BRIDGE_VLANDB_TINFO_ID]

Any new tunnel attributes can be nested under
BRIDGE_VLANDB_ENTRY_TUNNEL_INFO.

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

This patch adds support for vlan stats to be included when dumping vlan
information. We have to dump them only when explicitly requested (thus the
flag below) because that disables the vlan range compression and will make
the dump significantly larger. In order to request the stats to be
included we add a new dump attribute called BRIDGE_VLANDB_DUMP_FLAGS which
can affect dumps with the following first flag:
  - BRIDGE_VLANDB_DUMPF_STATS
The stats are intentionally nested and put into separate attributes to make
it easier for extending later since we plan to add per-vlan mcast stats,
drop stats and possibly STP stats. This is the last missing piece from the
new vlan API which makes the dumped vlan information complete.

A dump request which should include stats looks like:
 [BRIDGE_VLANDB_DUMP_FLAGS] |= BRIDGE_VLANDB_DUMPF_STATS

A vlandb entry attribute with stats looks like:
 [BRIDGE_VLANDB_ENTRY] = {
     [BRIDGE_VLANDB_ENTRY_STATS] = {
         [BRIDGE_VLANDB_STATS_RX_BYTES]
         [BRIDGE_VLANDB_STATS_RX_PACKETS]
         ...
     }
 }

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

This patch adds support for manipulating vlan/tunnel mappings. The
tunnel ids are globally unique and are one per-vlan. There were two
trickier issues - first in order to support vlan ranges we have to
compute the current tunnel id in the following way:
 - base tunnel id (attr) + current vlan id - starting vlan id
This is in line how the old API does vlan/tunnel mapping with ranges. We
already have the vlan range present, so it's redundant to add another
attribute for the tunnel range end. It's simply base tunnel id + vlan
range. And second to support removing mappings we need an out-of-band way
to tell the option manipulating function because there are no
special/reserved tunnel id values, so we use a vlan flag to denote the
operation is tunnel mapping removal.

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

Add a new option - BRIDGE_VLANDB_ENTRY_TUNNEL_ID which is used to dump
the tunnel id mapping. Since they're unique per vlan they can enter a
vlan range if they're consecutive, thus we can calculate the tunnel id
range map simply as: vlan range end id - vlan range start id. The
starting point is the tunnel id in BRIDGE_VLANDB_ENTRY_TUNNEL_ID. This
is similar to how the tunnel entries can be created in a range via the
old API (a vlan range maps to a tunnel range).

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

The first per-vlan option added is state, it is needed for EVPN and for
per-vlan STP. The state allows to control the forwarding on per-vlan
basis. The vlan state is considered only if the port state is forwarding
in order to avoid conflicts and be consistent. br_allowed_egress is
called only when the state is forwarding, but the ingress case is a bit
more complicated due to the fact that we may have the transition between
port:BR_STATE_FORWARDING -> vlan:BR_STATE_LEARNING which should still
allow the bridge to learn from the packet after vlan filtering and it will
be dropped after that. Also to optimize the pvid state check we keep a
copy in the vlan group to avoid one lookup. The state members are
modified with *_ONCE() to annotate the lockless access.

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