Commit f1dacd7a authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller
Browse files

net: dsa: create a helper that strips EtherType DSA headers on RX 



All header taggers open-code a memmove that is fairly not all that
obvious, and we can hide the details behind a helper function, since the
only thing specific to the driver is the length of the header tag.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1a8e628c

net/dsa/dsa_priv.h

+26 −0
Original line number Diff line number Diff line
@@ -452,6 +452,32 @@ static inline void dsa_default_offload_fwd_mark(struct sk_buff *skb) 
	skb->offload_fwd_mark = !!(dp->bridge_dev);

}



/* Helper for removing DSA header tags from packets in the RX path.

 * Must not be called before skb_pull(len).

 *                                                                 skb->data

 *                                                                         |

 *                                                                         v

 * |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |

 * +-----------------------+-----------------------+---------------+-------+

 * |    Destination MAC    |      Source MAC       |  DSA header   | EType |

 * +-----------------------+-----------------------+---------------+-------+

 *                                                 |               |

 * <----- len ----->                               <----- len ----->

 *                 |

 *       >>>>>>>   v

 *       >>>>>>>   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |

 *       >>>>>>>   +-----------------------+-----------------------+-------+

 *       >>>>>>>   |    Destination MAC    |      Source MAC       | EType |

 *                 +-----------------------+-----------------------+-------+

 *                                                                         ^

 *                                                                         |

 *                                                                 skb->data

 */

static inline void dsa_strip_etype_header(struct sk_buff *skb, int len)

{

	memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - len, 2 * ETH_ALEN);

}



/* switch.c */

int dsa_switch_register_notifier(struct dsa_switch *ds);

void dsa_switch_unregister_notifier(struct dsa_switch *ds);

net/dsa/tag_brcm.c

+2 −8
Original line number Diff line number Diff line
@@ -190,10 +190,7 @@ static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev) 
	if (!nskb)

		return nskb;



	/* Move the Ethernet DA and SA */

	memmove(nskb->data - ETH_HLEN,

		nskb->data - ETH_HLEN - BRCM_TAG_LEN,

		2 * ETH_ALEN);

	dsa_strip_etype_header(skb, BRCM_TAG_LEN);



	return nskb;

}
@@ -270,10 +267,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb, 


	dsa_default_offload_fwd_mark(skb);



	/* Move the Ethernet DA and SA */

	memmove(skb->data - ETH_HLEN,

		skb->data - ETH_HLEN - BRCM_LEG_TAG_LEN,

		2 * ETH_ALEN);

	dsa_strip_etype_header(skb, BRCM_LEG_TAG_LEN);



	return skb;

}

net/dsa/tag_dsa.c

+2 −6
Original line number Diff line number Diff line
@@ -312,14 +312,10 @@ static struct sk_buff *dsa_rcv_ll(struct sk_buff *skb, struct net_device *dev, 
		memcpy(dsa_header, new_header, DSA_HLEN);



		if (extra)

			memmove(skb->data - ETH_HLEN,

				skb->data - ETH_HLEN - extra,

				2 * ETH_ALEN);

			dsa_strip_etype_header(skb, extra);

	} else {

		skb_pull_rcsum(skb, DSA_HLEN);

		memmove(skb->data - ETH_HLEN,

			skb->data - ETH_HLEN - DSA_HLEN - extra,

			2 * ETH_ALEN);

		dsa_strip_etype_header(skb, DSA_HLEN + extra);

	}



	return skb;

net/dsa/tag_lan9303.c

+3 −2
Original line number Diff line number Diff line
@@ -112,8 +112,9 @@ static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev) 
	 * and the current ethertype field.

	 */

	skb_pull_rcsum(skb, 2 + 2);

	memmove(skb->data - ETH_HLEN, skb->data - (ETH_HLEN + LAN9303_TAG_LEN),

		2 * ETH_ALEN);



	dsa_strip_etype_header(skb, LAN9303_TAG_LEN);



	if (!(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU))

		dsa_default_offload_fwd_mark(skb);

net/dsa/tag_mtk.c

+1 −3
Original line number Diff line number Diff line
@@ -80,9 +80,7 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev) 
	/* Remove MTK tag and recalculate checksum. */

	skb_pull_rcsum(skb, MTK_HDR_LEN);



	memmove(skb->data - ETH_HLEN,

		skb->data - ETH_HLEN - MTK_HDR_LEN,

		2 * ETH_ALEN);

	dsa_strip_etype_header(skb, MTK_HDR_LEN);



	/* Get source port information */

	port = (hdr & MTK_HDR_RECV_SOURCE_PORT_MASK);