openwrt/target/linux/generic/patches-3.18/051-02-bridge-allow-setting-hash_max-multicast_router-if-in.patch

From 6ae4ae8e512bd229f806c22f8a2cd751e4f987c2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>
Date: Sat, 23 May 2015 03:12:34 +0200
Subject: [PATCH] bridge: allow setting hash_max + multicast_router if
 interface is down
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Network managers like netifd (used in OpenWRT for instance) try to
configure interface options after creation but before setting the
interface up.

Unfortunately the sysfs / bridge currently only allows to configure the
hash_max and multicast_router options when the bridge interface is up.
But since br_multicast_init() doesn't start any timers and only sets
default values and initializes timers it should be save to reconfigure
the default values after that, before things actually get active after
the bridge is set up.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/bridge/br_multicast.c |   24 +++---------------------
 1 file changed, 3 insertions(+), 21 deletions(-)

--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1948,11 +1948,9 @@ out:
 
 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
 {
-	int err = -ENOENT;
+	int err = -EINVAL;
 
 	spin_lock_bh(&br->multicast_lock);
-	if (!netif_running(br->dev))
-		goto unlock;
 
 	switch (val) {
 	case 0:
@@ -1963,13 +1961,8 @@ int br_multicast_set_router(struct net_b
 		br->multicast_router = val;
 		err = 0;
 		break;
-
-	default:
-		err = -EINVAL;
-		break;
 	}
 
-unlock:
 	spin_unlock_bh(&br->multicast_lock);
 
 	return err;
@@ -1978,11 +1971,9 @@ unlock:
 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
 {
 	struct net_bridge *br = p->br;
-	int err = -ENOENT;
+	int err = -EINVAL;
 
 	spin_lock(&br->multicast_lock);
-	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
-		goto unlock;
 
 	switch (val) {
 	case 0:
@@ -2004,13 +1995,8 @@ int br_multicast_set_port_router(struct
 
 		br_multicast_add_router(br, p);
 		break;
-
-	default:
-		err = -EINVAL;
-		break;
 	}
 
-unlock:
 	spin_unlock(&br->multicast_lock);
 
 	return err;
@@ -2115,15 +2101,11 @@ unlock:
 
 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
 {
-	int err = -ENOENT;
+	int err = -EINVAL;
 	u32 old;
 	struct net_bridge_mdb_htable *mdb;
 
 	spin_lock_bh(&br->multicast_lock);
-	if (!netif_running(br->dev))
-		goto unlock;
-
-	err = -EINVAL;
 	if (!is_power_of_2(val))
 		goto unlock;