Merge tag 'char-misc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregk...

[linux-2.6-microblaze.git] / net / dsa / tag_sja1105.c

diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 5b80a90..c054f48 100644 (file)
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -133,14 +133,44 @@ static struct sk_buff *sja1105_defer_xmit(struct dsa_port *dp,
        return NULL;
 }
 
+/* Send VLAN tags with a TPID that blends in with whatever VLAN protocol a
+ * bridge spanning ports of this switch might have.
+ */
 static u16 sja1105_xmit_tpid(struct dsa_port *dp)
 {
-       struct sja1105_port *sp = dp->priv;
+       struct dsa_switch *ds = dp->ds;
+       struct dsa_port *other_dp;
+       u16 proto;
+
+       /* Since VLAN awareness is global, then if this port is VLAN-unaware,
+        * all ports are. Use the VLAN-unaware TPID used for tag_8021q.
+        */
+       if (!dsa_port_is_vlan_filtering(dp))
+               return ETH_P_SJA1105;
+
+       /* Port is VLAN-aware, so there is a bridge somewhere (a single one,
+        * we're sure about that). It may not be on this port though, so we
+        * need to find it.
+        */
+       list_for_each_entry(other_dp, &ds->dst->ports, list) {
+               if (other_dp->ds != ds)
+                       continue;
+
+               if (!other_dp->bridge_dev)
+                       continue;
+
+               /* Error is returned only if CONFIG_BRIDGE_VLAN_FILTERING,
+                * which seems pointless to handle, as our port cannot become
+                * VLAN-aware in that case.
+                */
+               br_vlan_get_proto(other_dp->bridge_dev, &proto);
+
+               return proto;
+       }
 
-       if (unlikely(!dsa_port_is_sja1105(dp)))
-               return ETH_P_8021Q;
+       WARN_ONCE(1, "Port is VLAN-aware but cannot find associated bridge!\n");
 
-       return sp->xmit_tpid;
+       return ETH_P_SJA1105;
 }
 
 static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb,
@@ -168,6 +198,36 @@ static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb,
        return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), tx_vid);
 }
 
+/* Transform untagged control packets into pvid-tagged control packets so that
+ * all packets sent by this tagger are VLAN-tagged and we can configure the
+ * switch to drop untagged packets coming from the DSA master.
+ */
+static struct sk_buff *sja1105_pvid_tag_control_pkt(struct dsa_port *dp,
+                                                   struct sk_buff *skb, u8 pcp)
+{
+       __be16 xmit_tpid = htons(sja1105_xmit_tpid(dp));
+       struct vlan_ethhdr *hdr;
+
+       /* If VLAN tag is in hwaccel area, move it to the payload
+        * to deal with both cases uniformly and to ensure that
+        * the VLANs are added in the right order.
+        */
+       if (unlikely(skb_vlan_tag_present(skb))) {
+               skb = __vlan_hwaccel_push_inside(skb);
+               if (!skb)
+                       return NULL;
+       }
+
+       hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
+
+       /* If skb is already VLAN-tagged, leave that VLAN ID in place */
+       if (hdr->h_vlan_proto == xmit_tpid)
+               return skb;
+
+       return vlan_insert_tag(skb, xmit_tpid, (pcp << VLAN_PRIO_SHIFT) |
+                              SJA1105_DEFAULT_VLAN);
+}
+
 static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
                                    struct net_device *netdev)
 {
@@ -183,8 +243,13 @@ static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
         * but instead SPI-installed management routes. Part 2 of this
         * is the .port_deferred_xmit driver callback.
         */
-       if (unlikely(sja1105_is_link_local(skb)))
+       if (unlikely(sja1105_is_link_local(skb))) {
+               skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
+               if (!skb)
+                       return NULL;
+
                return sja1105_defer_xmit(dp, skb);
+       }
 
        return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
                             ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
@@ -213,6 +278,10 @@ static struct sk_buff *sja1110_xmit(struct sk_buff *skb,
                return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
                                     ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
 
+       skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
+       if (!skb)
+               return NULL;
+
        skb_push(skb, SJA1110_HEADER_LEN);
 
        dsa_alloc_etype_header(skb, SJA1110_HEADER_LEN);