net: dsa: tag_8021q: refactor RX VLAN parsing into a dedicated function

The added value of this function is that it can deal with both the case
where the VLAN header is in the skb head, as well as in the offload field.
This is something I was not able to do using other functions in the
network stack.

Since both ocelot-8021q and sja1105 need to do the same stuff, let's
make it a common service provided by tag_8021q.

This is done as refactoring for the new SJA1110 tagger, which partly
uses tag_8021q as well (just like SJA1105), and will be the third caller.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 16 deletions

diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
index 663b74793cfc..85ac85c3af8c 100644
--- a/net/dsa/tag_ocelot_8021q.c
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -41,29 +41,15 @@ static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
 				  struct net_device *netdev,
 				  struct packet_type *pt)
 {
-	int src_port, switch_id, qos_class;
-	u16 vid, tci;
+	int src_port, switch_id, subvlan;
 
-	skb_push_rcsum(skb, ETH_HLEN);
-	if (skb_vlan_tag_present(skb)) {
-		tci = skb_vlan_tag_get(skb);
-		__vlan_hwaccel_clear_tag(skb);
-	} else {
-		__skb_vlan_pop(skb, &tci);
-	}
-	skb_pull_rcsum(skb, ETH_HLEN);
-
-	vid = tci & VLAN_VID_MASK;
-	src_port = dsa_8021q_rx_source_port(vid);
-	switch_id = dsa_8021q_rx_switch_id(vid);
-	qos_class = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
+	dsa_8021q_rcv(skb, &src_port, &switch_id, &subvlan);
 
 	skb->dev = dsa_master_find_slave(netdev, switch_id, src_port);
 	if (!skb->dev)
 		return NULL;
 
 	skb->offload_fwd_mark = 1;
-	skb->priority = qos_class;
 
 	return skb;
 }