Merge branch 'dsa-fdb-isolation'

Vladimir Oltean says:

====================
DSA FDB isolation

There are use cases which need FDB isolation between standalone ports
and bridged ports, as well as isolation between ports of different
bridges. Most of these use cases are a result of the fact that packets
can now be partially forwarded by the software bridge, so one port might
need to send a packet to the CPU but its FDB lookup will see that it can
forward it directly to a bridge port where that packet was autonomously
learned. So the source port will attempt to shortcircuit the CPU and
forward autonomously, which it can't due to the forwarding isolation we
have in place. So we will have packet drops instead of proper operation.

Additionally, before DSA can implement IFF_UNICAST_FLT for standalone
ports, we must have control over which database we install FDB entries
corresponding to port MAC addresses in. We don't want to hinder the
operation of the bridging layer.

DSA does not have a driver API that encourages FDB isolation, so this
needs to be created. The basis for this is a new struct dsa_db which
annotates each FDB and MDB entry with the database it belongs to.

The sja1105 and felix drivers are modified to observe the dsa_db
argument, and therefore, enforce the FDB isolation.

Compared to the previous RFC patch series from August:
https://patchwork.kernel.org/project/netdevbpf/cover/20210818120150.892647-1-vladimir.oltean@nxp.com/

what is different is that I stopped trying to make SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE
blocking, instead I'm making use of the fact that DSA waits for switchdev FDB work
items to finish before a port leaves the bridge. This is possible since:
https://patchwork.kernel.org/project/netdevbpf/patch/20211024171757.3753288-7-vladimir.oltean@nxp.com/

Additionally, v2 is also rebased over the DSA LAG FDB work.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 70 insertions, 39 deletions

diff --git a/net/dsa/switch.c b/net/dsa/switch.c
index 0c2961cbc105..327d66bf7b47 100644
--- a/net/dsa/switch.c
+++ b/net/dsa/switch.c
@@ -96,7 +96,8 @@ static int dsa_switch_bridge_join(struct dsa_switch *ds,
 			return -EOPNOTSUPP;
 
 		err = ds->ops->port_bridge_join(ds, info->port, info->bridge,
-						&info->tx_fwd_offload);
+						&info->tx_fwd_offload,
+						info->extack);
 		if (err)
 			return err;
 	}
@@ -105,12 +106,13 @@ static int dsa_switch_bridge_join(struct dsa_switch *ds,
 	    ds->ops->crosschip_bridge_join) {
 		err = ds->ops->crosschip_bridge_join(ds, info->tree_index,
 						     info->sw_index,
-						     info->port, info->bridge);
+						     info->port, info->bridge,
+						     info->extack);
 		if (err)
 			return err;
 	}
 
-	return dsa_tag_8021q_bridge_join(ds, info);
+	return 0;
 }
 
 static int dsa_switch_sync_vlan_filtering(struct dsa_switch *ds,
@@ -186,7 +188,7 @@ static int dsa_switch_bridge_leave(struct dsa_switch *ds,
 			return err;
 	}
 
-	return dsa_tag_8021q_bridge_leave(ds, info);
+	return 0;
 }
 
 /* Matches for all upstream-facing ports (the CPU port and all upstream-facing
@@ -210,21 +212,41 @@ static bool dsa_port_host_address_match(struct dsa_port *dp,
 	return false;
 }
 
+static bool dsa_db_equal(const struct dsa_db *a, const struct dsa_db *b)
+{
+	if (a->type != b->type)
+		return false;
+
+	switch (a->type) {
+	case DSA_DB_PORT:
+		return a->dp == b->dp;
+	case DSA_DB_LAG:
+		return a->lag.dev == b->lag.dev;
+	case DSA_DB_BRIDGE:
+		return a->bridge.num == b->bridge.num;
+	default:
+		WARN_ON(1);
+		return false;
+	}
+}
+
 static struct dsa_mac_addr *dsa_mac_addr_find(struct list_head *addr_list,
-					      const unsigned char *addr,
-					      u16 vid)
+					      const unsigned char *addr, u16 vid,
+					      struct dsa_db db)
 {
 	struct dsa_mac_addr *a;
 
 	list_for_each_entry(a, addr_list, list)
-		if (ether_addr_equal(a->addr, addr) && a->vid == vid)
+		if (ether_addr_equal(a->addr, addr) && a->vid == vid &&
+		    dsa_db_equal(&a->db, &db))
 			return a;
 
 	return NULL;
 }
 
 static int dsa_port_do_mdb_add(struct dsa_port *dp,
-			       const struct switchdev_obj_port_mdb *mdb)
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
 {
 	struct dsa_switch *ds = dp->ds;
 	struct dsa_mac_addr *a;
@@ -233,11 +255,11 @@ static int dsa_port_do_mdb_add(struct dsa_port *dp,
 
 	/* No need to bother with refcounting for user ports */
 	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
-		return ds->ops->port_mdb_add(ds, port, mdb);
+		return ds->ops->port_mdb_add(ds, port, mdb, db);
 
 	mutex_lock(&dp->addr_lists_lock);
 
-	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid);
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
 	if (a) {
 		refcount_inc(&a->refcount);
 		goto out;
@@ -249,7 +271,7 @@ static int dsa_port_do_mdb_add(struct dsa_port *dp,
 		goto out;
 	}
 
-	err = ds->ops->port_mdb_add(ds, port, mdb);
+	err = ds->ops->port_mdb_add(ds, port, mdb, db);
 	if (err) {
 		kfree(a);
 		goto out;
@@ -257,6 +279,7 @@ static int dsa_port_do_mdb_add(struct dsa_port *dp,
 
 	ether_addr_copy(a->addr, mdb->addr);
 	a->vid = mdb->vid;
+	a->db = db;
 	refcount_set(&a->refcount, 1);
 	list_add_tail(&a->list, &dp->mdbs);
 
@@ -267,7 +290,8 @@ out:
 }
 
 static int dsa_port_do_mdb_del(struct dsa_port *dp,
-			       const struct switchdev_obj_port_mdb *mdb)
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
 {
 	struct dsa_switch *ds = dp->ds;
 	struct dsa_mac_addr *a;
@@ -276,11 +300,11 @@ static int dsa_port_do_mdb_del(struct dsa_port *dp,
 
 	/* No need to bother with refcounting for user ports */
 	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
-		return ds->ops->port_mdb_del(ds, port, mdb);
+		return ds->ops->port_mdb_del(ds, port, mdb, db);
 
 	mutex_lock(&dp->addr_lists_lock);
 
-	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid);
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
 	if (!a) {
 		err = -ENOENT;
 		goto out;
@@ -289,7 +313,7 @@ static int dsa_port_do_mdb_del(struct dsa_port *dp,
 	if (!refcount_dec_and_test(&a->refcount))
 		goto out;
 
-	err = ds->ops->port_mdb_del(ds, port, mdb);
+	err = ds->ops->port_mdb_del(ds, port, mdb, db);
 	if (err) {
 		refcount_set(&a->refcount, 1);
 		goto out;
@@ -305,7 +329,7 @@ out:
 }
 
 static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
-			       u16 vid)
+			       u16 vid, struct dsa_db db)
 {
 	struct dsa_switch *ds = dp->ds;
 	struct dsa_mac_addr *a;
@@ -314,11 +338,11 @@ static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
 
 	/* No need to bother with refcounting for user ports */
 	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
-		return ds->ops->port_fdb_add(ds, port, addr, vid);
+		return ds->ops->port_fdb_add(ds, port, addr, vid, db);
 
 	mutex_lock(&dp->addr_lists_lock);
 
-	a = dsa_mac_addr_find(&dp->fdbs, addr, vid);
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
 	if (a) {
 		refcount_inc(&a->refcount);
 		goto out;
@@ -330,7 +354,7 @@ static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
 		goto out;
 	}
 
-	err = ds->ops->port_fdb_add(ds, port, addr, vid);
+	err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
 	if (err) {
 		kfree(a);
 		goto out;
@@ -338,6 +362,7 @@ static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
 
 	ether_addr_copy(a->addr, addr);
 	a->vid = vid;
+	a->db = db;
 	refcount_set(&a->refcount, 1);
 	list_add_tail(&a->list, &dp->fdbs);
 
@@ -348,7 +373,7 @@ out:
 }
 
 static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
-			       u16 vid)
+			       u16 vid, struct dsa_db db)
 {
 	struct dsa_switch *ds = dp->ds;
 	struct dsa_mac_addr *a;
@@ -357,11 +382,11 @@ static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
 
 	/* No need to bother with refcounting for user ports */
 	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp)))
-		return ds->ops->port_fdb_del(ds, port, addr, vid);
+		return ds->ops->port_fdb_del(ds, port, addr, vid, db);
 
 	mutex_lock(&dp->addr_lists_lock);
 
-	a = dsa_mac_addr_find(&dp->fdbs, addr, vid);
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
 	if (!a) {
 		err = -ENOENT;
 		goto out;
@@ -370,7 +395,7 @@ static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
 	if (!refcount_dec_and_test(&a->refcount))
 		goto out;
 
-	err = ds->ops->port_fdb_del(ds, port, addr, vid);
+	err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
 	if (err) {
 		refcount_set(&a->refcount, 1);
 		goto out;
@@ -386,14 +411,15 @@ out:
 }
 
 static int dsa_switch_do_lag_fdb_add(struct dsa_switch *ds, struct dsa_lag *lag,
-				     const unsigned char *addr, u16 vid)
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
 {
 	struct dsa_mac_addr *a;
 	int err = 0;
 
 	mutex_lock(&lag->fdb_lock);
 
-	a = dsa_mac_addr_find(&lag->fdbs, addr, vid);
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
 	if (a) {
 		refcount_inc(&a->refcount);
 		goto out;
@@ -405,7 +431,7 @@ static int dsa_switch_do_lag_fdb_add(struct dsa_switch *ds, struct dsa_lag *lag,
 		goto out;
 	}
 
-	err = ds->ops->lag_fdb_add(ds, *lag, addr, vid);
+	err = ds->ops->lag_fdb_add(ds, *lag, addr, vid, db);
 	if (err) {
 		kfree(a);
 		goto out;
@@ -423,14 +449,15 @@ out:
 }
 
 static int dsa_switch_do_lag_fdb_del(struct dsa_switch *ds, struct dsa_lag *lag,
-				     const unsigned char *addr, u16 vid)
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
 {
 	struct dsa_mac_addr *a;
 	int err = 0;
 
 	mutex_lock(&lag->fdb_lock);
 
-	a = dsa_mac_addr_find(&lag->fdbs, addr, vid);
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
 	if (!a) {
 		err = -ENOENT;
 		goto out;
@@ -439,7 +466,7 @@ static int dsa_switch_do_lag_fdb_del(struct dsa_switch *ds, struct dsa_lag *lag,
 	if (!refcount_dec_and_test(&a->refcount))
 		goto out;
 
-	err = ds->ops->lag_fdb_del(ds, *lag, addr, vid);
+	err = ds->ops->lag_fdb_del(ds, *lag, addr, vid, db);
 	if (err) {
 		refcount_set(&a->refcount, 1);
 		goto out;
@@ -466,7 +493,8 @@ static int dsa_switch_host_fdb_add(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds) {
 		if (dsa_port_host_address_match(dp, info->sw_index,
 						info->port)) {
-			err = dsa_port_do_fdb_add(dp, info->addr, info->vid);
+			err = dsa_port_do_fdb_add(dp, info->addr, info->vid,
+						  info->db);
 			if (err)
 				break;
 		}
@@ -487,7 +515,8 @@ static int dsa_switch_host_fdb_del(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds) {
 		if (dsa_port_host_address_match(dp, info->sw_index,
 						info->port)) {
-			err = dsa_port_do_fdb_del(dp, info->addr, info->vid);
+			err = dsa_port_do_fdb_del(dp, info->addr, info->vid,
+						  info->db);
 			if (err)
 				break;
 		}
@@ -505,7 +534,7 @@ static int dsa_switch_fdb_add(struct dsa_switch *ds,
 	if (!ds->ops->port_fdb_add)
 		return -EOPNOTSUPP;
 
-	return dsa_port_do_fdb_add(dp, info->addr, info->vid);
+	return dsa_port_do_fdb_add(dp, info->addr, info->vid, info->db);
 }
 
 static int dsa_switch_fdb_del(struct dsa_switch *ds,
@@ -517,7 +546,7 @@ static int dsa_switch_fdb_del(struct dsa_switch *ds,
 	if (!ds->ops->port_fdb_del)
 		return -EOPNOTSUPP;
 
-	return dsa_port_do_fdb_del(dp, info->addr, info->vid);
+	return dsa_port_do_fdb_del(dp, info->addr, info->vid, info->db);
 }
 
 static int dsa_switch_lag_fdb_add(struct dsa_switch *ds,
@@ -532,7 +561,8 @@ static int dsa_switch_lag_fdb_add(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds)
 		if (dsa_port_offloads_lag(dp, info->lag))
 			return dsa_switch_do_lag_fdb_add(ds, info->lag,
-							 info->addr, info->vid);
+							 info->addr, info->vid,
+							 info->db);
 
 	return 0;
 }
@@ -549,7 +579,8 @@ static int dsa_switch_lag_fdb_del(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds)
 		if (dsa_port_offloads_lag(dp, info->lag))
 			return dsa_switch_do_lag_fdb_del(ds, info->lag,
-							 info->addr, info->vid);
+							 info->addr, info->vid,
+							 info->db);
 
 	return 0;
 }
@@ -604,7 +635,7 @@ static int dsa_switch_mdb_add(struct dsa_switch *ds,
 	if (!ds->ops->port_mdb_add)
 		return -EOPNOTSUPP;
 
-	return dsa_port_do_mdb_add(dp, info->mdb);
+	return dsa_port_do_mdb_add(dp, info->mdb, info->db);
 }
 
 static int dsa_switch_mdb_del(struct dsa_switch *ds,
@@ -616,7 +647,7 @@ static int dsa_switch_mdb_del(struct dsa_switch *ds,
 	if (!ds->ops->port_mdb_del)
 		return -EOPNOTSUPP;
 
-	return dsa_port_do_mdb_del(dp, info->mdb);
+	return dsa_port_do_mdb_del(dp, info->mdb, info->db);
 }
 
 static int dsa_switch_host_mdb_add(struct dsa_switch *ds,
@@ -631,7 +662,7 @@ static int dsa_switch_host_mdb_add(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds) {
 		if (dsa_port_host_address_match(dp, info->sw_index,
 						info->port)) {
-			err = dsa_port_do_mdb_add(dp, info->mdb);
+			err = dsa_port_do_mdb_add(dp, info->mdb, info->db);
 			if (err)
 				break;
 		}
@@ -652,7 +683,7 @@ static int dsa_switch_host_mdb_del(struct dsa_switch *ds,
 	dsa_switch_for_each_port(dp, ds) {
 		if (dsa_port_host_address_match(dp, info->sw_index,
 						info->port)) {
-			err = dsa_port_do_mdb_del(dp, info->mdb);
+			err = dsa_port_do_mdb_del(dp, info->mdb, info->db);
 			if (err)
 				break;
 		}