net: dsa: tag_brcm: Prepare for supporting prepended tag
In preparation for supporting the same Broadcom tag format, but instead
of inserted between the MAC SA and EtherType, prepended to the Ethernet
frame, restructure the code a little bit to make that possible and take
an offset parameter.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 9e082ba..771409a 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -59,7 +59,9 @@
#define BRCM_EG_TC_MASK 0x7
#define BRCM_EG_PID_MASK 0x1f
-static struct sk_buff *brcm_tag_xmit(struct sk_buff *skb, struct net_device *dev)
+static struct sk_buff *brcm_tag_xmit_ll(struct sk_buff *skb,
+ struct net_device *dev,
+ unsigned int offset)
{
struct dsa_port *dp = dsa_slave_to_port(dev);
u16 queue = skb_get_queue_mapping(skb);
@@ -70,10 +72,10 @@
skb_push(skb, BRCM_TAG_LEN);
- memmove(skb->data, skb->data + BRCM_TAG_LEN, 2 * ETH_ALEN);
+ if (offset)
+ memmove(skb->data, skb->data + BRCM_TAG_LEN, offset);
- /* Build the tag after the MAC Source Address */
- brcm_tag = skb->data + 2 * ETH_ALEN;
+ brcm_tag = skb->data + offset;
/* Set the ingress opcode, traffic class, tag enforcment is
* deprecated
@@ -94,8 +96,17 @@
return skb;
}
-static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
- struct packet_type *pt)
+static struct sk_buff *brcm_tag_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ /* Build the tag after the MAC Source Address */
+ return brcm_tag_xmit_ll(skb, dev, 2 * ETH_ALEN);
+}
+
+static struct sk_buff *brcm_tag_rcv_ll(struct sk_buff *skb,
+ struct net_device *dev,
+ struct packet_type *pt,
+ unsigned int offset)
{
int source_port;
u8 *brcm_tag;
@@ -103,8 +114,7 @@
if (unlikely(!pskb_may_pull(skb, BRCM_TAG_LEN)))
return NULL;
- /* skb->data points to the EtherType, the tag is right before it */
- brcm_tag = skb->data - 2;
+ brcm_tag = skb->data - offset;
/* The opcode should never be different than 0b000 */
if (unlikely((brcm_tag[0] >> BRCM_OPCODE_SHIFT) & BRCM_OPCODE_MASK))
@@ -126,12 +136,25 @@
/* Remove Broadcom tag and update checksum */
skb_pull_rcsum(skb, BRCM_TAG_LEN);
+ return skb;
+}
+
+static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt)
+{
+ struct sk_buff *nskb;
+
+ /* skb->data points to the EtherType, the tag is right before it */
+ nskb = brcm_tag_rcv_ll(skb, dev, pt, 2);
+ if (!nskb)
+ return nskb;
+
/* Move the Ethernet DA and SA */
- memmove(skb->data - ETH_HLEN,
- skb->data - ETH_HLEN - BRCM_TAG_LEN,
+ memmove(nskb->data - ETH_HLEN,
+ nskb->data - ETH_HLEN - BRCM_TAG_LEN,
2 * ETH_ALEN);
- return skb;
+ return nskb;
}
const struct dsa_device_ops brcm_netdev_ops = {