1 files changed, 69 insertions, 3 deletions

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index f785d24fcf23..f71d31d3aab4 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -1409,6 +1409,75 @@ static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
 	return 0;
 }
 
+static int dsa_slave_restore_vlan(struct net_device *vdev, int vid, void *arg)
+{
+	__be16 proto = vdev ? vlan_dev_vlan_proto(vdev) : htons(ETH_P_8021Q);
+
+	return dsa_slave_vlan_rx_add_vid(arg, proto, vid);
+}
+
+static int dsa_slave_clear_vlan(struct net_device *vdev, int vid, void *arg)
+{
+	__be16 proto = vdev ? vlan_dev_vlan_proto(vdev) : htons(ETH_P_8021Q);
+
+	return dsa_slave_vlan_rx_kill_vid(arg, proto, vid);
+}
+
+/* Keep the VLAN RX filtering list in sync with the hardware only if VLAN
+ * filtering is enabled. The baseline is that only ports that offload a
+ * VLAN-aware bridge are VLAN-aware, and standalone ports are VLAN-unaware,
+ * but there are exceptions for quirky hardware.
+ *
+ * If ds->vlan_filtering_is_global = true, then standalone ports which share
+ * the same switch with other ports that offload a VLAN-aware bridge are also
+ * inevitably VLAN-aware.
+ *
+ * To summarize, a DSA switch port offloads:
+ *
+ * - If standalone (this includes software bridge, software LAG):
+ *     - if ds->vlan_filtering_is_global = true AND there are bridges spanning
+ *       this switch chip which have vlan_filtering=1:
+ *         - the 8021q upper VLANs
+ *     - else (VLAN filtering is not global, or it is, but no port is under a
+ *       VLAN-aware bridge):
+ *         - no VLAN (any 8021q upper is a software VLAN)
+ *
+ * - If under a vlan_filtering=0 bridge which it offload:
+ *     - if ds->configure_vlan_while_not_filtering = true (default):
+ *         - the bridge VLANs. These VLANs are committed to hardware but inactive.
+ *     - else (deprecated):
+ *         - no VLAN. The bridge VLANs are not restored when VLAN awareness is
+ *           enabled, so this behavior is broken and discouraged.
+ *
+ * - If under a vlan_filtering=1 bridge which it offload:
+ *     - the bridge VLANs
+ *     - the 8021q upper VLANs
+ */
+int dsa_slave_manage_vlan_filtering(struct net_device *slave,
+				    bool vlan_filtering)
+{
+	int err;
+
+	if (vlan_filtering) {
+		slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+
+		err = vlan_for_each(slave, dsa_slave_restore_vlan, slave);
+		if (err) {
+			vlan_for_each(slave, dsa_slave_clear_vlan, slave);
+			slave->features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
+			return err;
+		}
+	} else {
+		err = vlan_for_each(slave, dsa_slave_clear_vlan, slave);
+		if (err)
+			return err;
+
+		slave->features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
+	}
+
+	return 0;
+}
+
 struct dsa_hw_port {
 	struct list_head list;
 	struct net_device *dev;
@@ -1802,7 +1871,6 @@ void dsa_slave_setup_tagger(struct net_device *slave)
 	struct dsa_slave_priv *p = netdev_priv(slave);
 	const struct dsa_port *cpu_dp = dp->cpu_dp;
 	struct net_device *master = cpu_dp->master;
-	const struct dsa_switch *ds = dp->ds;
 
 	slave->needed_headroom = cpu_dp->tag_ops->needed_headroom;
 	slave->needed_tailroom = cpu_dp->tag_ops->needed_tailroom;
@@ -1816,8 +1884,6 @@ void dsa_slave_setup_tagger(struct net_device *slave)
 	p->xmit = cpu_dp->tag_ops->xmit;
 
 	slave->features = master->vlan_features | NETIF_F_HW_TC;
-	if (ds->ops->port_vlan_add && ds->ops->port_vlan_del)
-		slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
 	slave->hw_features |= NETIF_F_HW_TC;
 	slave->features |= NETIF_F_LLTX;
 	if (slave->needed_tailroom)