Commit ef3f72fe authored by Christian Eggers's avatar Christian Eggers Committed by Jakub Kicinski
Browse files

net: dsa: trailer: 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 88fda8ee

net/dsa/tag_trailer.c

+2 −29
Original line number Diff line number Diff line
@@ -13,42 +13,15 @@ 
static struct sk_buff *trailer_xmit(struct sk_buff *skb, struct net_device *dev)

{

	struct dsa_port *dp = dsa_slave_to_port(dev);

	struct sk_buff *nskb;

	int padlen;

	u8 *trailer;



	/*

	 * We have to make sure that the trailer ends up as the very

	 * last 4 bytes of the packet.  This means that we have to pad

	 * the packet to the minimum ethernet frame size, if necessary,

	 * before adding the trailer.

	 */

	padlen = 0;

	if (skb->len < 60)

		padlen = 60 - skb->len;



	nskb = alloc_skb(NET_IP_ALIGN + skb->len + padlen + 4, 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));

	consume_skb(skb);



	if (padlen) {

		skb_put_zero(nskb, padlen);

	}



	trailer = skb_put(nskb, 4);

	trailer = skb_put(skb, 4);

	trailer[0] = 0x80;

	trailer[1] = 1 << dp->index;

	trailer[2] = 0x10;

	trailer[3] = 0x00;



	return nskb;

	return skb;

}



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

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