bridge: add sysfs hook to flush forwarding table

The RSTP daemon needs to be able to flush all dynamic forwarding
entries in the case of topology change.

This is a temporary interface. It will change to a netlink interface
before RSTP daemon is officially released.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index 0bc2aef8f9f3..2da22927d8dd 100644
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -137,6 +137,13 @@ static ssize_t show_hold_timer(struct net_bridge_port *p,
 }
 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 
+static ssize_t store_flush(struct net_bridge_port *p, unsigned long v)
+{
+        br_fdb_delete_by_port(p->br, p, 0); // Don't delete local entry
+        return 0;
+}
+static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
+
 static struct brport_attribute *brport_attrs[] = {
         &brport_attr_path_cost,
         &brport_attr_priority,
@@ -152,6 +159,7 @@ static struct brport_attribute *brport_attrs[] = {
         &brport_attr_message_age_timer,
         &brport_attr_forward_delay_timer,
         &brport_attr_hold_timer,
+        &brport_attr_flush,
         NULL
 };