Merge branch 'net-ndo_fdb_add-del-have-drivers-report-whether-they-no…

…tified'

Petr Machata says:

====================
net: ndo_fdb_add/del: Have drivers report whether they notified

Currently when FDB entries are added to or deleted from a VXLAN netdevice,
the VXLAN driver emits one notification, including the VXLAN-specific
attributes. The core however always sends a notification as well, a generic
one. Thus two notifications are unnecessarily sent for these operations. A
similar situation comes up with bridge driver, which also emits
notifications on its own.

 # ip link add name vx type vxlan id 1000 dstport 4789
 # bridge monitor fdb &
 [1] 1981693
 # bridge fdb add de:ad:be:ef:13:37 dev vx self dst 192.0.2.1
 de:ad:be:ef:13:37 dev vx dst 192.0.2.1 self permanent
 de:ad:be:ef:13:37 dev vx self permanent

In order to prevent this duplicity, add a parameter, bool *notified, to
ndo_fdb_add and ndo_fdb_del. The flag is primed to false, and if the callee
sends a notification on its own, it sets the flag to true, thus informing
the core that it should not generate another notification.

Patches #1 to #2 are concerned with the above.

In the remaining patches, #3 to #7, add a selftest. This takes place across
several patches. Many of the helpers we would like to use for the test are
in forwarding/lib.sh, whereas net/ is a more suitable place for the test,
so the libraries need to be massaged a bit first.
====================

Link: https://patch.msgid.link/cover.1731589511.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -13095,12 +13095,13 @@ static int i40e_get_phys_port_id(struct net_device *netdev,
  * @addr: the MAC address entry being added
  * @vid: VLAN ID
  * @flags: instructions from stack about fdb operation
+ * @notified: whether notification was emitted
  * @extack: netlink extended ack, unused currently
  */
 static int i40e_ndo_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			    struct net_device *dev,
 			    const unsigned char *addr, u16 vid,
-			    u16 flags,
+			    u16 flags, bool *notified,
 			    struct netlink_ext_ack *extack)
 {
 	struct i40e_netdev_priv *np = netdev_priv(dev);

drivers/net/ethernet/intel/ice/ice_main.c

@@ -6125,12 +6125,14 @@ ice_set_tx_maxrate(struct net_device *netdev, int queue_index, u32 maxrate)
  * @addr: the MAC address entry being added
  * @vid: VLAN ID
  * @flags: instructions from stack about fdb operation
+ * @notified: whether notification was emitted
  * @extack: netlink extended ack
  */
 static int
 ice_fdb_add(struct ndmsg *ndm, struct nlattr __always_unused *tb[],
 	    struct net_device *dev, const unsigned char *addr, u16 vid,
-	    u16 flags, struct netlink_ext_ack __always_unused *extack)
+	    u16 flags, bool *notified,
+	    struct netlink_ext_ack __always_unused *extack)
 {
 	int err;
 
@@ -6164,12 +6166,14 @@ ice_fdb_add(struct ndmsg *ndm, struct nlattr __always_unused *tb[],
  * @dev: the net device pointer
  * @addr: the MAC address entry being added
  * @vid: VLAN ID
+ * @notified: whether notification was emitted
  * @extack: netlink extended ack
  */
 static int
 ice_fdb_del(struct ndmsg *ndm, __always_unused struct nlattr *tb[],
 	    struct net_device *dev, const unsigned char *addr,
-	    __always_unused u16 vid, struct netlink_ext_ack *extack)
+	    __always_unused u16 vid, bool *notified,
+	    struct netlink_ext_ack *extack)
 {
 	int err;
 

drivers/net/ethernet/intel/igb/igb_main.c

@@ -2486,7 +2486,7 @@ static int igb_set_features(struct net_device *netdev,
 static int igb_ndo_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			   struct net_device *dev,
 			   const unsigned char *addr, u16 vid,
-			   u16 flags,
+			   u16 flags, bool *notified,
 			   struct netlink_ext_ack *extack)
 {
 	/* guarantee we can provide a unique filter for the unicast address */

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -9954,7 +9954,7 @@ static int ixgbe_set_features(struct net_device *netdev,
 static int ixgbe_ndo_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			     struct net_device *dev,
 			     const unsigned char *addr, u16 vid,
-			     u16 flags,
+			     u16 flags, bool *notified,
 			     struct netlink_ext_ack *extack)
 {
 	/* guarantee we can provide a unique filter for the unicast address */

drivers/net/ethernet/mscc/ocelot_net.c

@@ -730,7 +730,7 @@ static void ocelot_get_stats64(struct net_device *dev,
 static int ocelot_port_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			       struct net_device *dev,
 			       const unsigned char *addr,
-			       u16 vid, u16 flags,
+			       u16 vid, u16 flags, bool *notified,
 			       struct netlink_ext_ack *extack)
 {
 	struct ocelot_port_private *priv = netdev_priv(dev);
@@ -744,7 +744,7 @@ static int ocelot_port_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 static int ocelot_port_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
 			       struct net_device *dev,
 			       const unsigned char *addr, u16 vid,
-			       struct netlink_ext_ack *extack)
+			       bool *notified, struct netlink_ext_ack *extack)
 {
 	struct ocelot_port_private *priv = netdev_priv(dev);
 	struct ocelot_port *ocelot_port = &priv->port;

drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c

@@ -367,7 +367,7 @@ static int qlcnic_set_mac(struct net_device *netdev, void *p)
 
 static int qlcnic_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
 			struct net_device *netdev,
-			const unsigned char *addr, u16 vid,
+			const unsigned char *addr, u16 vid, bool *notified,
 			struct netlink_ext_ack *extack)
 {
 	struct qlcnic_adapter *adapter = netdev_priv(netdev);
@@ -394,7 +394,7 @@ static int qlcnic_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
 static int qlcnic_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			struct net_device *netdev,
 			const unsigned char *addr, u16 vid, u16 flags,
-			struct netlink_ext_ack *extack)
+			bool *notified, struct netlink_ext_ack *extack)
 {
 	struct qlcnic_adapter *adapter = netdev_priv(netdev);
 	int err = 0;

drivers/net/macvlan.c

@@ -1024,7 +1024,7 @@ static int macvlan_vlan_rx_kill_vid(struct net_device *dev,
 static int macvlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			   struct net_device *dev,
 			   const unsigned char *addr, u16 vid,
-			   u16 flags,
+			   u16 flags, bool *notified,
 			   struct netlink_ext_ack *extack)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
@@ -1049,7 +1049,7 @@ static int macvlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 
 static int macvlan_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
 			   struct net_device *dev,
-			   const unsigned char *addr, u16 vid,
+			   const unsigned char *addr, u16 vid, bool *notified,
 			   struct netlink_ext_ack *extack)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);

drivers/net/vxlan/vxlan_core.c

@@ -1241,7 +1241,7 @@ static int vxlan_fdb_parse(struct nlattr *tb[], struct vxlan_dev *vxlan,
 static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			 struct net_device *dev,
 			 const unsigned char *addr, u16 vid, u16 flags,
-			 struct netlink_ext_ack *extack)
+			 bool *notified, struct netlink_ext_ack *extack)
 {
 	struct vxlan_dev *vxlan = netdev_priv(dev);
 	/* struct net *net = dev_net(vxlan->dev); */
@@ -1277,6 +1277,9 @@ static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			       nhid, true, extack);
 	spin_unlock_bh(&vxlan->hash_lock[hash_index]);
 
+	if (!err)
+		*notified = true;
+
 	return err;
 }
 
@@ -1316,7 +1319,7 @@ int __vxlan_fdb_delete(struct vxlan_dev *vxlan,
 /* Delete entry (via netlink) */
 static int vxlan_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 			    struct net_device *dev,
-			    const unsigned char *addr, u16 vid,
+			    const unsigned char *addr, u16 vid, bool *notified,
 			    struct netlink_ext_ack *extack)
 {
 	struct vxlan_dev *vxlan = netdev_priv(dev);
@@ -1338,6 +1341,9 @@ static int vxlan_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 				 true);
 	spin_unlock_bh(&vxlan->hash_lock[hash_index]);
 
+	if (!err)
+		*notified = true;
+
 	return err;
 }
 

include/linux/netdevice.h

@@ -1248,12 +1248,17 @@ struct netdev_net_notifier {
  * int (*ndo_fdb_add)(struct ndmsg *ndm, struct nlattr *tb[],
  *		      struct net_device *dev,
  *		      const unsigned char *addr, u16 vid, u16 flags,
- *		      struct netlink_ext_ack *extack);
+ *		      bool *notified, struct netlink_ext_ack *extack);
  *	Adds an FDB entry to dev for addr.
+ *	Callee shall set *notified to true if it sent any appropriate
+ *	notification(s). Otherwise core will send a generic one.
  * int (*ndo_fdb_del)(struct ndmsg *ndm, struct nlattr *tb[],
  *		      struct net_device *dev,
- *		      const unsigned char *addr, u16 vid)
+ *		      const unsigned char *addr, u16 vid
+ *		      bool *notified, struct netlink_ext_ack *extack);
  *	Deletes the FDB entry from dev corresponding to addr.
+ *	Callee shall set *notified to true if it sent any appropriate
+ *	notification(s). Otherwise core will send a generic one.
  * int (*ndo_fdb_del_bulk)(struct nlmsghdr *nlh, struct net_device *dev,
  *			   struct netlink_ext_ack *extack);
  * int (*ndo_fdb_dump)(struct sk_buff *skb, struct netlink_callback *cb,
@@ -1525,12 +1530,15 @@ struct net_device_ops {
 					       const unsigned char *addr,
 					       u16 vid,
 					       u16 flags,
+					       bool *notified,
 					       struct netlink_ext_ack *extack);
 	int			(*ndo_fdb_del)(struct ndmsg *ndm,
 					       struct nlattr *tb[],
 					       struct net_device *dev,
 					       const unsigned char *addr,
-					       u16 vid, struct netlink_ext_ack *extack);
+					       u16 vid,
+					       bool *notified,
+					       struct netlink_ext_ack *extack);
 	int			(*ndo_fdb_del_bulk)(struct nlmsghdr *nlh,
 						    struct net_device *dev,
 						    struct netlink_ext_ack *extack);

net/bridge/br_fdb.c

@@ -1152,7 +1152,7 @@ static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
 			struct net_bridge_port *p, const unsigned char *addr,
 			u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
-			struct netlink_ext_ack *extack)
+			bool *notified, struct netlink_ext_ack *extack)
 {
 	int err = 0;
 
@@ -1183,6 +1183,8 @@ static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
 		spin_unlock_bh(&br->hash_lock);
 	}
 
+	if (!err)
+		*notified = true;
 	return err;
 }
 
@@ -1195,7 +1197,7 @@ static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 	       struct net_device *dev,
 	       const unsigned char *addr, u16 vid, u16 nlh_flags,
-	       struct netlink_ext_ack *extack)
+	       bool *notified, struct netlink_ext_ack *extack)
 {
 	struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
 	struct net_bridge_vlan_group *vg;
@@ -1258,10 +1260,10 @@ int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 
 		/* VID was specified, so use it. */
 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
-				   extack);
+				   notified, extack);
 	} else {
 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
-				   extack);
+				   notified, extack);
 		if (err || !vg || !vg->num_vlans)
 			goto out;
 
@@ -1273,7 +1275,7 @@ int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 			if (!br_vlan_should_use(v))
 				continue;
 			err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
-					   nfea_tb, extack);
+					   nfea_tb, notified, extack);
 			if (err)
 				goto out;
 		}
@@ -1285,7 +1287,7 @@ int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 
 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
 				       const struct net_bridge_port *p,
-				       const u8 *addr, u16 vlan)
+				       const u8 *addr, u16 vlan, bool *notified)
 {
 	struct net_bridge_fdb_entry *fdb;
 
@@ -1294,18 +1296,19 @@ static int fdb_delete_by_addr_and_port(struct net_bridge *br,
 		return -ENOENT;
 
 	fdb_delete(br, fdb, true);
+	*notified = true;
 
 	return 0;
 }
 
 static int __br_fdb_delete(struct net_bridge *br,
 			   const struct net_bridge_port *p,
-			   const unsigned char *addr, u16 vid)
+			   const unsigned char *addr, u16 vid, bool *notified)
 {
 	int err;
 
 	spin_lock_bh(&br->hash_lock);
-	err = fdb_delete_by_addr_and_port(br, p, addr, vid);
+	err = fdb_delete_by_addr_and_port(br, p, addr, vid, notified);
 	spin_unlock_bh(&br->hash_lock);
 
 	return err;
@@ -1314,7 +1317,7 @@ static int __br_fdb_delete(struct net_bridge *br,
 /* Remove neighbor entry with RTM_DELNEIGH */
 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 		  struct net_device *dev,
-		  const unsigned char *addr, u16 vid,
+		  const unsigned char *addr, u16 vid, bool *notified,
 		  struct netlink_ext_ack *extack)
 {
 	struct net_bridge_vlan_group *vg;
@@ -1337,19 +1340,19 @@ int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 	}
 
 	if (vid) {
-		err = __br_fdb_delete(br, p, addr, vid);
+		err = __br_fdb_delete(br, p, addr, vid, notified);
 	} else {
 		struct net_bridge_vlan *v;
 
 		err = -ENOENT;
-		err &= __br_fdb_delete(br, p, addr, 0);
+		err &= __br_fdb_delete(br, p, addr, 0, notified);
 		if (!vg || !vg->num_vlans)
 			return err;
 
 		list_for_each_entry(v, &vg->vlan_list, vlist) {
 			if (!br_vlan_should_use(v))
 				continue;
-			err &= __br_fdb_delete(br, p, addr, v->vid);
+			err &= __br_fdb_delete(br, p, addr, v->vid, notified);
 		}
 	}
 

net/bridge/br_private.h

@@ -853,12 +853,12 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 
 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 		  struct net_device *dev, const unsigned char *addr, u16 vid,
-		  struct netlink_ext_ack *extack);
+		  bool *notified, struct netlink_ext_ack *extack);
 int br_fdb_delete_bulk(struct nlmsghdr *nlh, struct net_device *dev,
 		       struct netlink_ext_ack *extack);
 int br_fdb_add(struct ndmsg *nlh, struct nlattr *tb[], struct net_device *dev,
 	       const unsigned char *addr, u16 vid, u16 nlh_flags,
-	       struct netlink_ext_ack *extack);
+	       bool *notified, struct netlink_ext_ack *extack);
 int br_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
 		struct net_device *dev, struct net_device *fdev, int *idx);
 int br_fdb_get(struct sk_buff *skb, struct nlattr *tb[], struct net_device *dev,

net/core/rtnetlink.c

@@ -4578,9 +4578,10 @@ static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
 	    netif_is_bridge_port(dev)) {
 		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
 		const struct net_device_ops *ops = br_dev->netdev_ops;
+		bool notified = false;
 
 		err = ops->ndo_fdb_add(ndm, tb, dev, addr, vid,
-				       nlh->nlmsg_flags, extack);
+				       nlh->nlmsg_flags, &notified, extack);
 		if (err)
 			goto out;
 		else
@@ -4589,16 +4590,18 @@ static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	/* Embedded bridge, macvlan, and any other device support */
 	if ((ndm->ndm_flags & NTF_SELF)) {
+		bool notified = false;
+
 		if (dev->netdev_ops->ndo_fdb_add)
 			err = dev->netdev_ops->ndo_fdb_add(ndm, tb, dev, addr,
 							   vid,
 							   nlh->nlmsg_flags,
-							   extack);
+							   &notified, extack);
 		else
 			err = ndo_dflt_fdb_add(ndm, tb, dev, addr, vid,
 					       nlh->nlmsg_flags);
 
-		if (!err) {
+		if (!err && !notified) {
 			rtnl_fdb_notify(dev, addr, vid, RTM_NEWNEIGH,
 					ndm->ndm_state);
 			ndm->ndm_flags &= ~NTF_SELF;
@@ -4698,11 +4701,13 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if ((!ndm->ndm_flags || ndm->ndm_flags & NTF_MASTER) &&
 	    netif_is_bridge_port(dev)) {
 		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
+		bool notified = false;
 
 		ops = br_dev->netdev_ops;
 		if (!del_bulk) {
 			if (ops->ndo_fdb_del)
-				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid, extack);
+				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid,
+						       &notified, extack);
 		} else {
 			if (ops->ndo_fdb_del_bulk)
 				err = ops->ndo_fdb_del_bulk(nlh, dev, extack);
@@ -4716,10 +4721,13 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	/* Embedded bridge, macvlan, and any other device support */
 	if (ndm->ndm_flags & NTF_SELF) {
+		bool notified = false;
+
 		ops = dev->netdev_ops;
 		if (!del_bulk) {
 			if (ops->ndo_fdb_del)
-				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid, extack);
+				err = ops->ndo_fdb_del(ndm, tb, dev, addr, vid,
+						       &notified, extack);
 			else
 				err = ndo_dflt_fdb_del(ndm, tb, dev, addr, vid);
 		} else {
@@ -4730,7 +4738,7 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
 		}
 
 		if (!err) {
-			if (!del_bulk)
+			if (!del_bulk && !notified)
 				rtnl_fdb_notify(dev, addr, vid, RTM_DELNEIGH,
 						ndm->ndm_state);
 			ndm->ndm_flags &= ~NTF_SELF;