[PATCH v3 net-next 10/12] net: dsa: replay VLANs installed on port when joining the bridge

Vladimir Oltean
2021-03-20T22:37:53Z

Currently this simple setup:

ip link add br0 type bridge vlan_filtering 1
ip link add bond0 type bond
ip link set bond0 master br0
ip link set swp0 master bond0

will not work because the bridge has created the PVID in br_add_if ->
nbp_vlan_init, and it has notified switchdev of the existence of VLAN 1,
but that was too early, since swp0 was not yet a lower of bond0, so it
had no reason to act upon that notification.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Changes in v3:
Made the br_vlan_replay shim return -EOPNOTSUPP.

include/linux/if_bridge.h | 10 ++++++
net/bridge/br_vlan.c | 71 +++++++++++++++++++++++++++++++++++++++
net/dsa/port.c | 6 ++++
3 files changed, 87 insertions(+)

diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index b564c4486a45..2cc35038a8ca 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -111,6 +111,8 @@ int br_vlan_get_pvid_rcu(const struct net_device *dev, u16 *p_pvid);
int br_vlan_get_proto(const struct net_device *dev, u16 *p_proto);
int br_vlan_get_info(const struct net_device *dev, u16 vid,
struct bridge_vlan_info *p_vinfo);
+int br_vlan_replay(struct net_device *br_dev, struct net_device *dev,
+ struct notifier_block *nb, struct netlink_ext_ack *extack);
#else
static inline bool br_vlan_enabled(const struct net_device *dev)
{
@@ -137,6 +139,14 @@ static inline int br_vlan_get_info(const struct net_device *dev, u16 vid,
{
return -EINVAL;
}
+
+static inline int br_vlan_replay(struct net_device *br_dev,
+ struct net_device *dev,
+ struct notifier_block *nb,
+ struct netlink_ext_ack *extack)
+{
+ return -EOPNOTSUPP;
+}
#endif

#if IS_ENABLED(CONFIG_BRIDGE)
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 8829f621b8ec..45a4eac1b217 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -1751,6 +1751,77 @@ void br_vlan_notify(const struct net_bridge *br,
kfree_skb(skb);
}

+static int br_vlan_replay_one(struct notifier_block *nb,
+ struct net_device *dev,
+ struct switchdev_obj_port_vlan *vlan,
+ struct netlink_ext_ack *extack)
+{
+ struct switchdev_notifier_port_obj_info obj_info = {
+ .info = {
+ .dev = dev,
+ .extack = extack,
+ },
+ .obj = &vlan->obj,
+ };
+ int err;
+
+ err = nb->notifier_call(nb, SWITCHDEV_PORT_OBJ_ADD, &obj_info);
+ return notifier_to_errno(err);
+}
+
+int br_vlan_replay(struct net_device *br_dev, struct net_device *dev,
+ struct notifier_block *nb, struct netlink_ext_ack *extack)
+{
+ struct net_bridge_vlan_group *vg;
+ struct net_bridge_vlan *v;
+ struct net_bridge_port *p;
+ struct net_bridge *br;
+ int err = 0;
+ u16 pvid;
+
+ ASSERT_RTNL();
+
+ if (!netif_is_bridge_master(br_dev))
+ return -EINVAL;
+
+ if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev))
+ return -EINVAL;
+
+ if (netif_is_bridge_master(dev)) {
+ br = netdev_priv(dev);
+ vg = br_vlan_group(br);
+ p = NULL;
+ } else {
+ p = br_port_get_rtnl(dev);
+ if (WARN_ON(!p))
+ return -EINVAL;
+ vg = nbp_vlan_group(p);
+ br = p->br;
+ }
+
+ if (!vg)
+ return 0;
+
+ pvid = br_get_pvid(vg);
+
+ list_for_each_entry(v, &vg->vlan_list, vlist) {
+ struct switchdev_obj_port_vlan vlan = {
+ .obj.orig_dev = dev,
+ .obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
+ .flags = br_vlan_flags(v, pvid),
+ .vid = v->vid,
+ };
+
+ if (!br_vlan_should_use(v))
+ continue;
+
+ br_vlan_replay_one(nb, dev, &vlan, extack);
+ if (err)
+ return err;
+ }
+
+ return err;
+}
/* check if v_curr can enter a range ending in range_end */
bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr,
const struct net_bridge_vlan *range_end)
diff --git a/net/dsa/port.c b/net/dsa/port.c
index d21a511f1e16..84775e253ee8 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -209,6 +209,12 @@ static int dsa_port_switchdev_sync(struct dsa_port *dp,
if (err && err != -EOPNOTSUPP)
return err;

+ err = br_vlan_replay(br, brport_dev,
+ &dsa_slave_switchdev_blocking_notifier,
+ extack);
+ if (err && err != -EOPNOTSUPP)
+ return err;
+
return 0;
}

--
2.25.1