Commit 88fda8ee authored by Christian Eggers's avatar Christian Eggers Committed by Jakub Kicinski
Browse files

net: dsa: tag_ksz: don't allocate additional memory for padding/tagging 



The caller (dsa_slave_xmit) guarantees that the frame length is at least
ETH_ZLEN and that enough memory for tail tagging is available.

Signed-off-by: default avatarChristian Eggers <ceggers@arri.de>
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent a3b0b647

net/dsa/tag_ksz.c

+9 −64
Original line number Original line Diff line number Diff line
@@ -14,46 +14,6 @@ 
#define KSZ_EGRESS_TAG_LEN		1

#define KSZ_EGRESS_TAG_LEN		1

#define KSZ_INGRESS_TAG_LEN		1

#define KSZ_INGRESS_TAG_LEN		1





static struct sk_buff *ksz_common_xmit(struct sk_buff *skb,

				       struct net_device *dev, int len)

{

	struct sk_buff *nskb;

	int padlen;



	padlen = (skb->len >= ETH_ZLEN) ? 0 : ETH_ZLEN - skb->len;



	if (skb_tailroom(skb) >= padlen + len) {

		/* Let dsa_slave_xmit() free skb */

		if (__skb_put_padto(skb, skb->len + padlen, false))

			return NULL;



		nskb = skb;

	} else {

		nskb = alloc_skb(NET_IP_ALIGN + skb->len +

				 padlen + len, GFP_ATOMIC);

		if (!nskb)

			return NULL;

		skb_reserve(nskb, NET_IP_ALIGN);



		skb_reset_mac_header(nskb);

		skb_set_network_header(nskb,

				       skb_network_header(skb) - skb->head);

		skb_set_transport_header(nskb,

					 skb_transport_header(skb) - skb->head);

		skb_copy_and_csum_dev(skb, skb_put(nskb, skb->len));



		/* Let skb_put_padto() free nskb, and let dsa_slave_xmit() free

		 * skb

		 */

		if (skb_put_padto(nskb, nskb->len + padlen))

			return NULL;



		consume_skb(skb);

	}



	return nskb;

}



static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,

static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,

				      struct net_device *dev,

				      struct net_device *dev,

				      unsigned int port, unsigned int len)

				      unsigned int port, unsigned int len)
@@ -90,23 +50,18 @@ static struct sk_buff *ksz_common_rcv(struct sk_buff *skb, 
static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)

static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)

{

{

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct sk_buff *nskb;

	u8 *tag;

	u8 *tag;

	u8 *addr;

	u8 *addr;





	nskb = ksz_common_xmit(skb, dev, KSZ_INGRESS_TAG_LEN);

	if (!nskb)

		return NULL;



	/* Tag encoding */

	/* Tag encoding */

	tag = skb_put(nskb, KSZ_INGRESS_TAG_LEN);

	tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);

	addr = skb_mac_header(nskb);

	addr = skb_mac_header(skb);





	*tag = 1 << dp->index;

	*tag = 1 << dp->index;

	if (is_link_local_ether_addr(addr))

	if (is_link_local_ether_addr(addr))

		*tag |= KSZ8795_TAIL_TAG_OVERRIDE;

		*tag |= KSZ8795_TAIL_TAG_OVERRIDE;





	return nskb;

	return skb;

}

}





static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev,

static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev,
@@ -156,18 +111,13 @@ static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, 
				    struct net_device *dev)

				    struct net_device *dev)

{

{

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct sk_buff *nskb;

	__be16 *tag;

	__be16 *tag;

	u8 *addr;

	u8 *addr;

	u16 val;

	u16 val;





	nskb = ksz_common_xmit(skb, dev, KSZ9477_INGRESS_TAG_LEN);

	if (!nskb)

		return NULL;



	/* Tag encoding */

	/* Tag encoding */

	tag = skb_put(nskb, KSZ9477_INGRESS_TAG_LEN);

	tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);

	addr = skb_mac_header(nskb);

	addr = skb_mac_header(skb);





	val = BIT(dp->index);

	val = BIT(dp->index);
@@ -176,7 +126,7 @@ static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, 




	*tag = cpu_to_be16(val);

	*tag = cpu_to_be16(val);





	return nskb;

	return skb;

}

}





static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev,

static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev,
@@ -213,24 +163,19 @@ static struct sk_buff *ksz9893_xmit(struct sk_buff *skb, 
				    struct net_device *dev)

				    struct net_device *dev)

{

{

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct sk_buff *nskb;

	u8 *addr;

	u8 *addr;

	u8 *tag;

	u8 *tag;





	nskb = ksz_common_xmit(skb, dev, KSZ_INGRESS_TAG_LEN);

	if (!nskb)

		return NULL;



	/* Tag encoding */

	/* Tag encoding */

	tag = skb_put(nskb, KSZ_INGRESS_TAG_LEN);

	tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);

	addr = skb_mac_header(nskb);

	addr = skb_mac_header(skb);





	*tag = BIT(dp->index);

	*tag = BIT(dp->index);





	if (is_link_local_ether_addr(addr))

	if (is_link_local_ether_addr(addr))

		*tag |= KSZ9893_TAIL_TAG_OVERRIDE;

		*tag |= KSZ9893_TAIL_TAG_OVERRIDE;





	return nskb;

	return skb;

}

}





static const struct dsa_device_ops ksz9893_netdev_ops = {

static const struct dsa_device_ops ksz9893_netdev_ops = {