Merge branch 'dsa-receive-path-simplifications'

Florian Fainelli says:

====================
net: dsa: Receive path simplifications

This patch series does factor the common code found in all tag implementations
into dsa_switch_rcv(). The original motivation was to add GRO support, but this
may be a lot of work with unclear benefits at this point.

Changes in v2:
- take care of tag_mtk.c in the process
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/dsa.h

@@ -124,7 +124,7 @@ struct dsa_switch_tree {
 	 * protocol to use.
 	 */
 	struct net_device	*master_netdev;
-	int			(*rcv)(struct sk_buff *skb,
+	struct sk_buff *	(*rcv)(struct sk_buff *skb,
 				       struct net_device *dev,
 				       struct packet_type *pt,
 				       struct net_device *orig_dev);

net/dsa/dsa.c

@@ -23,6 +23,7 @@
 #include <linux/sysfs.h>
 #include <linux/phy_fixed.h>
 #include <linux/gpio/consumer.h>
+#include <linux/etherdevice.h>
 #include <net/dsa.h>
 #include "dsa_priv.h"
 
@@ -900,13 +901,34 @@ static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
 			  struct packet_type *pt, struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
+	struct sk_buff *nskb = NULL;
 
 	if (unlikely(dst == NULL)) {
 		kfree_skb(skb);
 		return 0;
 	}
 
-	return dst->rcv(skb, dev, pt, orig_dev);
+	skb = skb_unshare(skb, GFP_ATOMIC);
+	if (!skb)
+		return 0;
+
+	nskb = dst->rcv(skb, dev, pt, orig_dev);
+	if (!nskb) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	skb = nskb;
+	skb_push(skb, ETH_HLEN);
+	skb->pkt_type = PACKET_HOST;
+	skb->protocol = eth_type_trans(skb, skb->dev);
+
+	skb->dev->stats.rx_packets++;
+	skb->dev->stats.rx_bytes += skb->len;
+
+	netif_receive_skb(skb);
+
+	return 0;
 }
 
 static struct packet_type dsa_pack_type __read_mostly = {

net/dsa/dsa_priv.h

@@ -17,8 +17,9 @@
 
 struct dsa_device_ops {
 	struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
-	int (*rcv)(struct sk_buff *skb, struct net_device *dev,
-		   struct packet_type *pt, struct net_device *orig_dev);
+	struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev,
+			       struct packet_type *pt,
+			       struct net_device *orig_dev);
 };
 
 struct dsa_slave_priv {

net/dsa/tag_brcm.c

@@ -92,23 +92,17 @@ out_free:
 	return NULL;
 }
 
-static int brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
-			struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
+				    struct packet_type *pt,
+				    struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
 	int source_port;
 	u8 *brcm_tag;
 
-	if (unlikely(dst == NULL))
-		goto out_drop;
-
 	ds = dst->cpu_switch;
 
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (skb == NULL)
-		goto out;
-
 	if (unlikely(!pskb_may_pull(skb, BRCM_TAG_LEN)))
 		goto out_drop;
 
@@ -140,22 +134,12 @@ static int brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 		skb->data - ETH_HLEN - BRCM_TAG_LEN,
 		2 * ETH_ALEN);
 
-	skb_push(skb, ETH_HLEN);
-	skb->pkt_type = PACKET_HOST;
 	skb->dev = ds->ports[source_port].netdev;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops brcm_netdev_ops = {

net/dsa/tag_dsa.c

@@ -68,8 +68,9 @@ out_free:
 	return NULL;
 }
 
-static int dsa_rcv(struct sk_buff *skb, struct net_device *dev,
-		   struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
+			       struct packet_type *pt,
+			       struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
@@ -77,13 +78,6 @@ static int dsa_rcv(struct sk_buff *skb, struct net_device *dev,
 	int source_device;
 	int source_port;
 
-	if (unlikely(dst == NULL))
-		goto out_drop;
-
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (skb == NULL)
-		goto out;
-
 	if (unlikely(!pskb_may_pull(skb, DSA_HLEN)))
 		goto out_drop;
 
@@ -165,21 +159,11 @@ static int dsa_rcv(struct sk_buff *skb, struct net_device *dev,
 	}
 
 	skb->dev = ds->ports[source_port].netdev;
-	skb_push(skb, ETH_HLEN);
-	skb->pkt_type = PACKET_HOST;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops dsa_netdev_ops = {

net/dsa/tag_edsa.c

@@ -81,8 +81,9 @@ out_free:
 	return NULL;
 }
 
-static int edsa_rcv(struct sk_buff *skb, struct net_device *dev,
-		    struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *edsa_rcv(struct sk_buff *skb, struct net_device *dev,
+				struct packet_type *pt,
+				struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
@@ -90,13 +91,6 @@ static int edsa_rcv(struct sk_buff *skb, struct net_device *dev,
 	int source_device;
 	int source_port;
 
-	if (unlikely(dst == NULL))
-		goto out_drop;
-
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (skb == NULL)
-		goto out;
-
 	if (unlikely(!pskb_may_pull(skb, EDSA_HLEN)))
 		goto out_drop;
 
@@ -184,21 +178,11 @@ static int edsa_rcv(struct sk_buff *skb, struct net_device *dev,
 	}
 
 	skb->dev = ds->ports[source_port].netdev;
-	skb_push(skb, ETH_HLEN);
-	skb->pkt_type = PACKET_HOST;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops edsa_netdev_ops = {

net/dsa/tag_mtk.c

@@ -47,21 +47,15 @@ out_free:
 	return NULL;
 }
 
-static int mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
-		       struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
+				   struct packet_type *pt,
+				   struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
 	int port;
 	__be16 *phdr, hdr;
 
-	if (unlikely(!dst))
-		goto out_drop;
-
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (!skb)
-		goto out;
-
 	if (unlikely(!pskb_may_pull(skb, MTK_HDR_LEN)))
 		goto out_drop;
 
@@ -92,24 +86,12 @@ static int mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 	if (!ds->ports[port].netdev)
 		goto out_drop;
 
-	/* Update skb & forward the frame accordingly */
-	skb_push(skb, ETH_HLEN);
-
-	skb->pkt_type = PACKET_HOST;
 	skb->dev = ds->ports[port].netdev;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops mtk_netdev_ops = {

net/dsa/tag_qca.c

@@ -66,8 +66,9 @@ out_free:
 	return NULL;
 }
 
-static int qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
-		       struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
+				   struct packet_type *pt,
+				   struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
@@ -75,13 +76,6 @@ static int qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 	int port;
 	__be16 *phdr, hdr;
 
-	if (unlikely(!dst))
-		goto out_drop;
-
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (!skb)
-		goto out;
-
 	if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN)))
 		goto out_drop;
 
@@ -115,22 +109,12 @@ static int qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 		goto out_drop;
 
 	/* Update skb & forward the frame accordingly */
-	skb_push(skb, ETH_HLEN);
-	skb->pkt_type = PACKET_HOST;
 	skb->dev = ds->ports[port].netdev;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops qca_netdev_ops = {

net/dsa/tag_trailer.c

@@ -58,22 +58,17 @@ static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev)
 	return nskb;
 }
 
-static int trailer_rcv(struct sk_buff *skb, struct net_device *dev,
-		       struct packet_type *pt, struct net_device *orig_dev)
+static struct sk_buff *trailer_rcv(struct sk_buff *skb, struct net_device *dev,
+				   struct packet_type *pt,
+				   struct net_device *orig_dev)
 {
 	struct dsa_switch_tree *dst = dev->dsa_ptr;
 	struct dsa_switch *ds;
 	u8 *trailer;
 	int source_port;
 
-	if (unlikely(dst == NULL))
-		goto out_drop;
 	ds = dst->cpu_switch;
 
-	skb = skb_unshare(skb, GFP_ATOMIC);
-	if (skb == NULL)
-		goto out;
-
 	if (skb_linearize(skb))
 		goto out_drop;
 
@@ -89,21 +84,11 @@ static int trailer_rcv(struct sk_buff *skb, struct net_device *dev,
 	pskb_trim_rcsum(skb, skb->len - 4);
 
 	skb->dev = ds->ports[source_port].netdev;
-	skb_push(skb, ETH_HLEN);
-	skb->pkt_type = PACKET_HOST;
-	skb->protocol = eth_type_trans(skb, skb->dev);
-
-	skb->dev->stats.rx_packets++;
-	skb->dev->stats.rx_bytes += skb->len;
 
-	netif_receive_skb(skb);
-
-	return 0;
+	return skb;
 
 out_drop:
-	kfree_skb(skb);
-out:
-	return 0;
+	return NULL;
 }
 
 const struct dsa_device_ops trailer_netdev_ops = {