net: bridge: switchdev: differentiate new VLANs from changed ones

br_switchdev_port_vlan_add() currently emits a SWITCHDEV_PORT_OBJ_ADD
event with a SWITCHDEV_OBJ_ID_PORT_VLAN for 2 distinct cases:

- a struct net_bridge_vlan got created
- an existing struct net_bridge_vlan was modified

This makes it impossible for switchdev drivers to properly balance
PORT_OBJ_ADD with PORT_OBJ_DEL events, so if we want to allow that to
happen, we must provide a way for drivers to distinguish between a
VLAN with changed flags and a new one.

Annotate struct switchdev_obj_port_vlan with a "bool changed" that
distinguishes the 2 cases above.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index d353793..92cc763 100644 (file)
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h
@@ -81,6 +81,13 @@ struct switchdev_obj_port_vlan {
        struct switchdev_obj obj;
        u16 flags;
        u16 vid;
+       /* If set, the notifier signifies a change of one of the following
+        * flags for a VLAN that already exists:
+        * - BRIDGE_VLAN_INFO_PVID
+        * - BRIDGE_VLAN_INFO_UNTAGGED
+        * Entries with BRIDGE_VLAN_INFO_BRENTRY unset are not notified at all.
+        */
+       bool changed;
 };
 
 #define SWITCHDEV_OBJ_PORT_VLAN(OBJ) \

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 2661dda..48bc61e 100644 (file)
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1985,7 +1985,7 @@ void br_switchdev_mdb_notify(struct net_device *dev,
                             struct net_bridge_port_group *pg,
                             int type);
 int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
-                              struct netlink_ext_ack *extack);
+                              bool changed, struct netlink_ext_ack *extack);
 int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid);
 void br_switchdev_init(struct net_bridge *br);
 
@@ -2052,8 +2052,8 @@ static inline int br_switchdev_set_port_flag(struct net_bridge_port *p,
        return 0;
 }
 
-static inline int br_switchdev_port_vlan_add(struct net_device *dev,
-                                            u16 vid, u16 flags,
+static inline int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid,
+                                            u16 flags, bool changed,
                                             struct netlink_ext_ack *extack)
 {
        return -EOPNOTSUPP;

diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index f8fbaaa..fb51153 100644 (file)
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -160,13 +160,14 @@ br_switchdev_fdb_notify(struct net_bridge *br,
 }
 
 int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
-                              struct netlink_ext_ack *extack)
+                              bool changed, struct netlink_ext_ack *extack)
 {
        struct switchdev_obj_port_vlan v = {
                .obj.orig_dev = dev,
                .obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
                .flags = flags,
                .vid = vid,
+               .changed = changed,
        };
 
        return switchdev_port_obj_add(dev, &v.obj, extack);

diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 0ad55a1..7557e90 100644 (file)
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -109,7 +109,7 @@ static int __vlan_vid_add(struct net_device *dev, struct net_bridge *br,
        /* Try switchdev op first. In case it is not supported, fallback to
         * 8021q add.
         */
-       err = br_switchdev_port_vlan_add(dev, v->vid, flags, extack);
+       err = br_switchdev_port_vlan_add(dev, v->vid, flags, false, extack);
        if (err == -EOPNOTSUPP)
                return vlan_vid_add(dev, br->vlan_proto, v->vid);
        v->priv_flags |= BR_VLFLAG_ADDED_BY_SWITCHDEV;
@@ -303,7 +303,7 @@ static int __vlan_add(struct net_bridge_vlan *v, u16 flags,
        } else {
                if (br_vlan_should_use(v)) {
                        err = br_switchdev_port_vlan_add(dev, v->vid, flags,
-                                                        extack);
+                                                        false, extack);
                        if (err && err != -EOPNOTSUPP)
                                goto out;
                }
@@ -714,7 +714,7 @@ static int br_vlan_add_existing(struct net_bridge *br,
         */
        if (becomes_brentry || would_change) {
                err = br_switchdev_port_vlan_add(br->dev, vlan->vid, flags,
-                                                extack);
+                                                would_change, extack);
                if (err && err != -EOPNOTSUPP)
                        return err;
        }
@@ -1289,8 +1289,8 @@ int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags,
 
                if (would_change) {
                        /* Pass the flags to the hardware bridge */
-                       ret = br_switchdev_port_vlan_add(port->dev, vid,
-                                                        flags, extack);
+                       ret = br_switchdev_port_vlan_add(port->dev, vid, flags,
+                                                        true, extack);
                        if (ret && ret != -EOPNOTSUPP)
                                return ret;
                }