Merge branch 'bridge_default_pvid'

Vladislav Yasevich says:

====================
bridge: Add vlan filtering support for default pvid

This series adds default pvid support to vlan filtering in the bridge.
VLAN 1 (as recommended by 802.1q spec) is used as default pvid on ports.
Then the user can over-ride this configuration by configuring their
own vlan information.
The user can additionally change the default value through the
sysfs interface (netlink coming shortly).
The user can turn off default pvid functionality by setting default
pvid to 0.
This series changes the default behavior of the bridge when
vlan filtering is turned on.  Currently, ports without any vlan
filtering configured will not recevie any traffic at all.  This patch
changes the behavior of the above ports to receive only untagged traffic.

Since v3:
- allocated 'changed' bitmap on the heap and re-arrange code to clean it up.
- remove extra blank lines.
- Fix patch1 to build by itself.
- Fix error recover to not add vlan 0.
- Restructure nbp_vlan_init to remove uneeded variable.

Since v2:
- Fix handling of invalid values in sysfs interface.
- Add some additional log messages.
- Fix default_pvid handling when vlan filtering is compiled out.
- Fix sparse issues with new code.
- Fix how we located the old default pvid (added a helper function).

Since v1:
- Add ability to turn off default_pvid settings.
- Drop the automiatic filtering support based on configured vlan devices (will
  be its own series)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_device.c

@@ -88,12 +88,17 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 static int br_dev_init(struct net_device *dev)
 {
 	struct net_bridge *br = netdev_priv(dev);
+	int err;
 
 	br->stats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 	if (!br->stats)
 		return -ENOMEM;
 
-	return 0;
+	err = br_vlan_init(br);
+	if (err)
+		free_percpu(br->stats);
+
+	return err;
 }
 
 static int br_dev_open(struct net_device *dev)
@@ -389,5 +394,4 @@ void br_dev_setup(struct net_device *dev)
 	br_netfilter_rtable_init(br);
 	br_stp_timer_init(br);
 	br_multicast_init(br);
-	br_vlan_init(br);
 }

net/bridge/br_if.c

@@ -500,6 +500,9 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
 	if (br_fdb_insert(br, p, dev->dev_addr, 0))
 		netdev_err(dev, "failed insert local address bridge forwarding table\n");
 
+	if (nbp_vlan_init(p))
+		netdev_err(dev, "failed to initialize vlan filtering on this port\n");
+
 	spin_lock_bh(&br->lock);
 	changed_addr = br_stp_recalculate_bridge_id(br);
 

net/bridge/br_private.h

@@ -299,6 +299,7 @@ struct net_bridge
 #ifdef CONFIG_BRIDGE_VLAN_FILTERING
 	u8				vlan_enabled;
 	__be16				vlan_proto;
+	u16				default_pvid;
 	struct net_port_vlans __rcu	*vlan_info;
 #endif
 };
@@ -604,11 +605,13 @@ bool br_vlan_find(struct net_bridge *br, u16 vid);
 void br_recalculate_fwd_mask(struct net_bridge *br);
 int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val);
 int br_vlan_set_proto(struct net_bridge *br, unsigned long val);
-void br_vlan_init(struct net_bridge *br);
+int br_vlan_init(struct net_bridge *br);
+int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val);
 int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags);
 int nbp_vlan_delete(struct net_bridge_port *port, u16 vid);
 void nbp_vlan_flush(struct net_bridge_port *port);
 bool nbp_vlan_find(struct net_bridge_port *port, u16 vid);
+int nbp_vlan_init(struct net_bridge_port *port);
 
 static inline struct net_port_vlans *br_get_vlan_info(
 						const struct net_bridge *br)
@@ -641,11 +644,11 @@ static inline int br_vlan_get_tag(const struct sk_buff *skb, u16 *vid)
 
 static inline u16 br_get_pvid(const struct net_port_vlans *v)
 {
-	/* Return just the VID if it is set, or VLAN_N_VID (invalid vid) if
-	 * vid wasn't set
-	 */
+	if (!v)
+		return 0;
+
 	smp_rmb();
-	return v->pvid ?: VLAN_N_VID;
+	return v->pvid;
 }
 
 static inline int br_vlan_enabled(struct net_bridge *br)
@@ -704,8 +707,9 @@ static inline void br_recalculate_fwd_mask(struct net_bridge *br)
 {
 }
 
-static inline void br_vlan_init(struct net_bridge *br)
+static inline int br_vlan_init(struct net_bridge *br)
 {
+	return 0;
 }
 
 static inline int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags)
@@ -738,13 +742,18 @@ static inline bool nbp_vlan_find(struct net_bridge_port *port, u16 vid)
 	return false;
 }
 
+static inline int nbp_vlan_init(struct net_bridge_port *port)
+{
+	return 0;
+}
+
 static inline u16 br_vlan_get_tag(const struct sk_buff *skb, u16 *tag)
 {
 	return 0;
 }
 static inline u16 br_get_pvid(const struct net_port_vlans *v)
 {
-	return VLAN_N_VID;	/* Returns invalid vid */
+	return 0;
 }
 
 static inline int br_vlan_enabled(struct net_bridge *br)

net/bridge/br_sysfs_br.c

@@ -725,6 +725,22 @@ static ssize_t vlan_protocol_store(struct device *d,
 	return store_bridge_parm(d, buf, len, br_vlan_set_proto);
 }
 static DEVICE_ATTR_RW(vlan_protocol);
+
+static ssize_t default_pvid_show(struct device *d,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct net_bridge *br = to_bridge(d);
+	return sprintf(buf, "%d\n", br->default_pvid);
+}
+
+static ssize_t default_pvid_store(struct device *d,
+				  struct device_attribute *attr,
+				  const char *buf, size_t len)
+{
+	return store_bridge_parm(d, buf, len, br_vlan_set_default_pvid);
+}
+static DEVICE_ATTR_RW(default_pvid);
 #endif
 
 static struct attribute *bridge_attrs[] = {
@@ -771,6 +787,7 @@ static struct attribute *bridge_attrs[] = {
 #ifdef CONFIG_BRIDGE_VLAN_FILTERING
 	&dev_attr_vlan_filtering.attr,
 	&dev_attr_vlan_protocol.attr,
+	&dev_attr_default_pvid.attr,
 #endif
 	NULL
 };

net/bridge/br_vlan.c

@@ -223,7 +223,7 @@ bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
 		 * See if pvid is set on this port.  That tells us which
 		 * vlan untagged or priority-tagged traffic belongs to.
 		 */
-		if (pvid == VLAN_N_VID)
+		if (!pvid)
 			goto drop;
 
 		/* PVID is set on this port.  Any untagged or priority-tagged
@@ -292,7 +292,7 @@ bool br_should_learn(struct net_bridge_port *p, struct sk_buff *skb, u16 *vid)
 
 	if (!*vid) {
 		*vid = br_get_pvid(v);
-		if (*vid == VLAN_N_VID)
+		if (!*vid)
 			return false;
 
 		return true;
@@ -499,9 +499,141 @@ int br_vlan_set_proto(struct net_bridge *br, unsigned long val)
 	goto unlock;
 }
 
-void br_vlan_init(struct net_bridge *br)
+static bool vlan_default_pvid(struct net_port_vlans *pv, u16 vid)
+{
+	return pv && vid == pv->pvid && test_bit(vid, pv->untagged_bitmap);
+}
+
+static void br_vlan_disable_default_pvid(struct net_bridge *br)
+{
+	struct net_bridge_port *p;
+	u16 pvid = br->default_pvid;
+
+	/* Disable default_pvid on all ports where it is still
+	 * configured.
+	 */
+	if (vlan_default_pvid(br_get_vlan_info(br), pvid))
+		br_vlan_delete(br, pvid);
+
+	list_for_each_entry(p, &br->port_list, list) {
+		if (vlan_default_pvid(nbp_get_vlan_info(p), pvid))
+			nbp_vlan_delete(p, pvid);
+	}
+
+	br->default_pvid = 0;
+}
+
+static int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid)
+{
+	struct net_bridge_port *p;
+	u16 old_pvid;
+	int err = 0;
+	unsigned long *changed;
+
+	changed = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
+			  GFP_KERNEL);
+	if (!changed)
+		return -ENOMEM;
+
+	old_pvid = br->default_pvid;
+
+	/* Update default_pvid config only if we do not conflict with
+	 * user configuration.
+	 */
+	if ((!old_pvid || vlan_default_pvid(br_get_vlan_info(br), old_pvid)) &&
+	    !br_vlan_find(br, pvid)) {
+		err = br_vlan_add(br, pvid,
+				  BRIDGE_VLAN_INFO_PVID |
+				  BRIDGE_VLAN_INFO_UNTAGGED);
+		if (err)
+			goto out;
+		br_vlan_delete(br, old_pvid);
+		set_bit(0, changed);
+	}
+
+	list_for_each_entry(p, &br->port_list, list) {
+		/* Update default_pvid config only if we do not conflict with
+		 * user configuration.
+		 */
+		if ((old_pvid &&
+		     !vlan_default_pvid(nbp_get_vlan_info(p), old_pvid)) ||
+		    nbp_vlan_find(p, pvid))
+			continue;
+
+		err = nbp_vlan_add(p, pvid,
+				   BRIDGE_VLAN_INFO_PVID |
+				   BRIDGE_VLAN_INFO_UNTAGGED);
+		if (err)
+			goto err_port;
+		nbp_vlan_delete(p, old_pvid);
+		set_bit(p->port_no, changed);
+	}
+
+	br->default_pvid = pvid;
+
+out:
+	kfree(changed);
+	return err;
+
+err_port:
+	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
+		if (!test_bit(p->port_no, changed))
+			continue;
+
+		if (old_pvid)
+			nbp_vlan_add(p, old_pvid,
+				     BRIDGE_VLAN_INFO_PVID |
+				     BRIDGE_VLAN_INFO_UNTAGGED);
+		nbp_vlan_delete(p, pvid);
+	}
+
+	if (test_bit(0, changed)) {
+		if (old_pvid)
+			br_vlan_add(br, old_pvid,
+				    BRIDGE_VLAN_INFO_PVID |
+				    BRIDGE_VLAN_INFO_UNTAGGED);
+		br_vlan_delete(br, pvid);
+	}
+	goto out;
+}
+
+int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
+{
+	u16 pvid = val;
+	int err = 0;
+
+	if (val >= VLAN_VID_MASK)
+		return -EINVAL;
+
+	if (!rtnl_trylock())
+		return restart_syscall();
+
+	if (pvid == br->default_pvid)
+		goto unlock;
+
+	/* 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;
+	}
+
+	if (!pvid)
+		br_vlan_disable_default_pvid(br);
+	else
+		err = __br_vlan_set_default_pvid(br, pvid);
+
+unlock:
+	rtnl_unlock();
+	return err;
+}
+
+int br_vlan_init(struct net_bridge *br)
 {
 	br->vlan_proto = htons(ETH_P_8021Q);
+	br->default_pvid = 1;
+	return br_vlan_add(br, 1,
+			   BRIDGE_VLAN_INFO_PVID | BRIDGE_VLAN_INFO_UNTAGGED);
 }
 
 /* Must be protected by RTNL.
@@ -593,3 +725,12 @@ bool nbp_vlan_find(struct net_bridge_port *port, u16 vid)
 	rcu_read_unlock();
 	return found;
 }
+
+int nbp_vlan_init(struct net_bridge_port *p)
+{
+	return p->br->default_pvid ?
+			nbp_vlan_add(p, p->br->default_pvid,
+				     BRIDGE_VLAN_INFO_PVID |
+				     BRIDGE_VLAN_INFO_UNTAGGED) :
+			0;
+}