bridge: mrp: Add support for role MRA

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>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 0162c1370ecb..caa6914a3e53 100644
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -222,6 +222,7 @@ enum {
 	IFLA_BRIDGE_MRP_START_TEST_INTERVAL,
 	IFLA_BRIDGE_MRP_START_TEST_MAX_MISS,
 	IFLA_BRIDGE_MRP_START_TEST_PERIOD,
+	IFLA_BRIDGE_MRP_START_TEST_MONITOR,
 	__IFLA_BRIDGE_MRP_START_TEST_MAX,
 };
 
@@ -249,6 +250,7 @@ struct br_mrp_start_test {
 	__u32 interval;
 	__u32 max_miss;
 	__u32 period;
+	__u32 monitor;
 };
 
 struct bridge_stp_xstats {