Merge branch 'bridge-sysfs-rtnl-notifications'

Xin Long says:

====================
bridge: support sending rntl info when we set attributes through sysfs/ioctl

This patchset is used to support sending rntl info to user in some places,
and ensure that whenever those attributes change internally or from sysfs,
that a netlink notification is sent out to listeners.

It also make some adjustment in bridge sysfs so that we can implement this
easily.

I've done some tests on this patchset, like:
[br_sysfs]
  1. change all the attribute values of br or brif:
  $ echo $value > /sys/class/net/br0/bridge/{*}
  $ echo $value > /sys/class/net/br0/brif/eth1/{*}

  2. meanwhile, on another terminal to observe the msg:
  $ bridge monitor

[br_ioctl]
  1. in bridge-utils package, do some changes in br_set, let brctl command
  use ioctl to set attribute:
         if ((ret = set_sysfs(path, value)) < 0) { -->
         if (1) {

  $ brctl set*

  2. meanwhile, on another terminal to observe the msg:
  $ bridge monitor

This test covers all the attributes that brctl and sysfs support to set.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_ioctl.c

@@ -112,7 +112,9 @@ static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
 static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 {
 	struct net_bridge *br = netdev_priv(dev);
+	struct net_bridge_port *p = NULL;
 	unsigned long args[4];
+	int ret = -EOPNOTSUPP;
 
 	if (copy_from_user(args, rq->ifr_data, sizeof(args)))
 		return -EFAULT;
@@ -182,25 +184,29 @@ static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
-		return br_set_forward_delay(br, args[1]);
+		ret = br_set_forward_delay(br, args[1]);
+		break;
 
 	case BRCTL_SET_BRIDGE_HELLO_TIME:
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
-		return br_set_hello_time(br, args[1]);
+		ret = br_set_hello_time(br, args[1]);
+		break;
 
 	case BRCTL_SET_BRIDGE_MAX_AGE:
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
-		return br_set_max_age(br, args[1]);
+		ret = br_set_max_age(br, args[1]);
+		break;
 
 	case BRCTL_SET_AGEING_TIME:
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
-		return br_set_ageing_time(br, args[1]);
+		ret = br_set_ageing_time(br, args[1]);
+		break;
 
 	case BRCTL_GET_PORT_INFO:
 	{
@@ -240,20 +246,19 @@ static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 			return -EPERM;
 
 		br_stp_set_enabled(br, args[1]);
-		return 0;
+		ret = 0;
+		break;
 
 	case BRCTL_SET_BRIDGE_PRIORITY:
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
 		br_stp_set_bridge_priority(br, args[1]);
-		return 0;
+		ret = 0;
+		break;
 
 	case BRCTL_SET_PORT_PRIORITY:
 	{
-		struct net_bridge_port *p;
-		int ret;
-
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
@@ -263,14 +268,11 @@ static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 		else
 			ret = br_stp_set_port_priority(p, args[2]);
 		spin_unlock_bh(&br->lock);
-		return ret;
+		break;
 	}
 
 	case BRCTL_SET_PATH_COST:
 	{
-		struct net_bridge_port *p;
-		int ret;
-
 		if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 
@@ -280,8 +282,7 @@ static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 		else
 			ret = br_stp_set_path_cost(p, args[2]);
 		spin_unlock_bh(&br->lock);
-
-		return ret;
+		break;
 	}
 
 	case BRCTL_GET_FDB_ENTRIES:
@@ -289,7 +290,14 @@ static int old_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 				       args[2], args[3]);
 	}
 
-	return -EOPNOTSUPP;
+	if (!ret) {
+		if (p)
+			br_ifinfo_notify(RTM_NEWLINK, p);
+		else
+			netdev_state_change(br->dev);
+	}
+
+	return ret;
 }
 
 static int old_deviceless(struct net *net, void __user *uarg)

net/bridge/br_sysfs_br.c

@@ -43,7 +43,14 @@ static ssize_t store_bridge_parm(struct device *d,
 	if (endp == buf)
 		return -EINVAL;
 
+	if (!rtnl_trylock())
+		return restart_syscall();
+
 	err = (*set)(br, val);
+	if (!err)
+		netdev_state_change(br->dev);
+	rtnl_unlock();
+
 	return err ? err : len;
 }
 
@@ -101,15 +108,7 @@ static ssize_t ageing_time_show(struct device *d,
 
 static int set_ageing_time(struct net_bridge *br, unsigned long val)
 {
-	int ret;
-
-	if (!rtnl_trylock())
-		return restart_syscall();
-
-	ret = br_set_ageing_time(br, val);
-	rtnl_unlock();
-
-	return ret;
+	return br_set_ageing_time(br, val);
 }
 
 static ssize_t ageing_time_store(struct device *d,
@@ -128,27 +127,18 @@ static ssize_t stp_state_show(struct device *d,
 }
 
 
+static int set_stp_state(struct net_bridge *br, unsigned long val)
+{
+	br_stp_set_enabled(br, val);
+
+	return 0;
+}
+
 static ssize_t stp_state_store(struct device *d,
 			       struct device_attribute *attr, const char *buf,
 			       size_t len)
 {
-	struct net_bridge *br = to_bridge(d);
-	char *endp;
-	unsigned long val;
-
-	if (!ns_capable(dev_net(br->dev)->user_ns, CAP_NET_ADMIN))
-		return -EPERM;
-
-	val = simple_strtoul(buf, &endp, 0);
-	if (endp == buf)
-		return -EINVAL;
-
-	if (!rtnl_trylock())
-		return restart_syscall();
-	br_stp_set_enabled(br, val);
-	rtnl_unlock();
-
-	return len;
+	return store_bridge_parm(d, buf, len, set_stp_state);
 }
 static DEVICE_ATTR_RW(stp_state);
 
@@ -160,29 +150,22 @@ static ssize_t group_fwd_mask_show(struct device *d,
 	return sprintf(buf, "%#x\n", br->group_fwd_mask);
 }
 
-
-static ssize_t group_fwd_mask_store(struct device *d,
-				    struct device_attribute *attr,
-				    const char *buf,
-				    size_t len)
+static int set_group_fwd_mask(struct net_bridge *br, unsigned long val)
 {
-	struct net_bridge *br = to_bridge(d);
-	char *endp;
-	unsigned long val;
-
-	if (!ns_capable(dev_net(br->dev)->user_ns, CAP_NET_ADMIN))
-		return -EPERM;
-
-	val = simple_strtoul(buf, &endp, 0);
-	if (endp == buf)
-		return -EINVAL;
-
 	if (val & BR_GROUPFWD_RESTRICTED)
 		return -EINVAL;
 
 	br->group_fwd_mask = val;
 
-	return len;
+	return 0;
+}
+
+static ssize_t group_fwd_mask_store(struct device *d,
+				    struct device_attribute *attr,
+				    const char *buf,
+				    size_t len)
+{
+	return store_bridge_parm(d, buf, len, set_group_fwd_mask);
 }
 static DEVICE_ATTR_RW(group_fwd_mask);
 
@@ -328,6 +311,7 @@ static ssize_t group_addr_store(struct device *d,
 
 	br->group_addr_set = true;
 	br_recalculate_fwd_mask(br);
+	netdev_state_change(br->dev);
 
 	rtnl_unlock();
 
@@ -336,17 +320,17 @@ static ssize_t group_addr_store(struct device *d,
 
 static DEVICE_ATTR_RW(group_addr);
 
+static int set_flush(struct net_bridge *br, unsigned long val)
+{
+	br_fdb_flush(br);
+	return 0;
+}
+
 static ssize_t flush_store(struct device *d,
 			   struct device_attribute *attr,
 			   const char *buf, size_t len)
 {
-	struct net_bridge *br = to_bridge(d);
-
-	if (!ns_capable(dev_net(br->dev)->user_ns, CAP_NET_ADMIN))
-		return -EPERM;
-
-	br_fdb_flush(br);
-	return len;
+	return store_bridge_parm(d, buf, len, set_flush);
 }
 static DEVICE_ATTR_WO(flush);
 

net/bridge/br_sysfs_if.c

@@ -61,7 +61,6 @@ static int store_flag(struct net_bridge_port *p, unsigned long v,
 	if (flags != p->flags) {
 		p->flags = flags;
 		br_port_flags_change(p, mask);
-		br_ifinfo_notify(RTM_NEWLINK, p);
 	}
 	return 0;
 }
@@ -253,8 +252,10 @@ static ssize_t brport_store(struct kobject *kobj,
 			spin_lock_bh(&p->br->lock);
 			ret = brport_attr->store(p, val);
 			spin_unlock_bh(&p->br->lock);
-			if (ret == 0)
+			if (!ret) {
+				br_ifinfo_notify(RTM_NEWLINK, p);
 				ret = count;
+			}
 		}
 		rtnl_unlock();
 	}

net/bridge/br_vlan.c

@@ -651,15 +651,7 @@ int __br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
 
 int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
 {
-	int err;
-
-	if (!rtnl_trylock())
-		return restart_syscall();
-
-	err = __br_vlan_filter_toggle(br, val);
-	rtnl_unlock();
-
-	return err;
+	return __br_vlan_filter_toggle(br, val);
 }
 
 int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
@@ -713,18 +705,10 @@ int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
 
 int br_vlan_set_proto(struct net_bridge *br, unsigned long val)
 {
-	int err;
-
 	if (val != ETH_P_8021Q && val != ETH_P_8021AD)
 		return -EPROTONOSUPPORT;
 
-	if (!rtnl_trylock())
-		return restart_syscall();
-
-	err = __br_vlan_set_proto(br, htons(val));
-	rtnl_unlock();
-
-	return err;
+	return __br_vlan_set_proto(br, htons(val));
 }
 
 static bool vlan_default_pvid(struct net_bridge_vlan_group *vg, u16 vid)
@@ -855,21 +839,17 @@ int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
 	if (val >= VLAN_VID_MASK)
 		return -EINVAL;
 
-	if (!rtnl_trylock())
-		return restart_syscall();
-
 	if (pvid == br->default_pvid)
-		goto unlock;
+		goto out;
 
 	/* Only allow default pvid change when filtering is disabled */
 	if (br->vlan_enabled) {
 		pr_info_once("Please disable vlan filtering to change default_pvid\n");
 		err = -EPERM;
-		goto unlock;
+		goto out;
 	}
 	err = __br_vlan_set_default_pvid(br, pvid);
-unlock:
-	rtnl_unlock();
+out:
 	return err;
 }