[Patch v4 net-next 3/3] net: bridge: mcast: Notify on mdb offload failure

[Joseph Huang]

Notify user space on mdb offload failure if
mdb_offload_fail_notification is enabled.

Signed-off-by: Joseph Huang <joseph.hu...@garmin.com>
Acked-by: Nikolay Aleksandrov <ra...@blackwall.org>
---
 net/bridge/br_mdb.c       | 26 +++++++++++++++++++++-----
 net/bridge/br_private.h   |  9 +++++++++
 net/bridge/br_switchdev.c |  4 ++++
 3 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 0639691cd19b..5f53f387d251 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -519,16 +519,17 @@ static size_t rtnl_mdb_nlmsg_size(const struct 
net_bridge_port_group *pg)
               rtnl_mdb_nlmsg_pg_size(pg);
 }
 
-void br_mdb_notify(struct net_device *dev,
-                  struct net_bridge_mdb_entry *mp,
-                  struct net_bridge_port_group *pg,
-                  int type)
+static void __br_mdb_notify(struct net_device *dev,
+                           struct net_bridge_mdb_entry *mp,
+                           struct net_bridge_port_group *pg,
+                           int type, bool notify_switchdev)
 {
        struct net *net = dev_net(dev);
        struct sk_buff *skb;
        int err = -ENOBUFS;
 
-       br_switchdev_mdb_notify(dev, mp, pg, type);
+       if (notify_switchdev)
+               br_switchdev_mdb_notify(dev, mp, pg, type);
 
        skb = nlmsg_new(rtnl_mdb_nlmsg_size(pg), GFP_ATOMIC);
        if (!skb)
@@ -546,6 +547,21 @@ void br_mdb_notify(struct net_device *dev,
        rtnl_set_sk_err(net, RTNLGRP_MDB, err);
 }
 
+void br_mdb_notify(struct net_device *dev,
+                  struct net_bridge_mdb_entry *mp,
+                  struct net_bridge_port_group *pg,
+                  int type)
+{
+       __br_mdb_notify(dev, mp, pg, type, true);
+}
+
+void br_mdb_flag_change_notify(struct net_device *dev,
+                              struct net_bridge_mdb_entry *mp,
+                              struct net_bridge_port_group *pg)
+{
+       __br_mdb_notify(dev, mp, pg, RTM_NEWMDB, false);
+}
+
 static int nlmsg_populate_rtr_fill(struct sk_buff *skb,
                                   struct net_device *dev,
                                   int ifindex, u16 vid, u32 pid,
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 02188b7ff8e6..fc43ccc06ccb 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1005,6 +1005,8 @@ int br_mdb_hash_init(struct net_bridge *br);
 void br_mdb_hash_fini(struct net_bridge *br);
 void br_mdb_notify(struct net_device *dev, struct net_bridge_mdb_entry *mp,
                   struct net_bridge_port_group *pg, int type);
+void br_mdb_flag_change_notify(struct net_device *dev, struct 
net_bridge_mdb_entry *mp,
+                              struct net_bridge_port_group *pg);
 void br_rtr_notify(struct net_device *dev, struct net_bridge_mcast_port *pmctx,
                   int type);
 void br_multicast_del_pg(struct net_bridge_mdb_entry *mp,
@@ -1354,6 +1356,13 @@ br_multicast_set_pg_offload_flags(struct 
net_bridge_port_group *p,
        p->flags |= (offloaded ? MDB_PG_FLAGS_OFFLOAD :
                MDB_PG_FLAGS_OFFLOAD_FAILED);
 }
+
+static inline bool
+br_mdb_should_notify(const struct net_bridge *br, u8 changed_flags)
+{
+       return br_opt_get(br, BROPT_MDB_OFFLOAD_FAIL_NOTIFICATION) &&
+               (changed_flags & MDB_PG_FLAGS_OFFLOAD_FAILED);
+}
 #else
 static inline int br_multicast_rcv(struct net_bridge_mcast **brmctx,
                                   struct net_bridge_mcast_port **pmctx,
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index 57e1863edf93..bbdf6a3ba941 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -504,6 +504,7 @@ static void br_switchdev_mdb_complete(struct net_device 
*dev, int err, void *pri
        struct net_bridge_mdb_entry *mp;
        struct net_bridge_port *port = data->port;
        struct net_bridge *br = port->br;
+       u8 old_flags;
 
        if (err == -EOPNOTSUPP)
                goto notsupp;
@@ -517,7 +518,10 @@ static void br_switchdev_mdb_complete(struct net_device 
*dev, int err, void *pri
                if (p->key.port != port)
                        continue;
 
+               old_flags = p->flags;
                br_multicast_set_pg_offload_flags(p, !err);
+               if (br_mdb_should_notify(br, old_flags ^ p->flags))
+                       br_mdb_flag_change_notify(br->dev, mp, p);
        }
 out:
        spin_unlock_bh(&br->multicast_lock);
-- 
2.49.0