Commit d212f87b authored by Stephen Hemminger's avatar Stephen Hemminger Committed by David S. Miller
Browse files

[NET]: IPV6 checksum offloading in network devices 



The existing model for checksum offload does not correctly handle
devices that can offload IPV4 and IPV6 only. The NETIF_F_HW_CSUM flag
implies device can do any arbitrary protocol.

This patch:
 * adds NETIF_F_IPV6_CSUM for those devices
 * fixes bnx2 and tg3 devices that need it
 * add NETIF_F_IPV6_CSUM to ipv6 output (incl GSO)
 * fixes assumptions about NETIF_F_ALL_CSUM in nat
 * adjusts bridge union of checksumming computation

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d3d6dd3a

drivers/net/bnx2.c

+3 −3
Original line number Diff line number Diff line
@@ -6490,10 +6490,10 @@ bnx2_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) 
	memcpy(dev->perm_addr, bp->mac_addr, 6);

	bp->name = board_info[ent->driver_data].name;



	if (CHIP_NUM(bp) == CHIP_NUM_5709)

		dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;

	else

	dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;

	if (CHIP_NUM(bp) == CHIP_NUM_5709)

		dev->features |= NETIF_F_IPV6_CSUM;



#ifdef BCM_VLAN

	dev->features |= NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX;

#endif

drivers/net/tg3.c

+3 −4
Original line number Diff line number Diff line
@@ -11944,12 +11944,11 @@ static int __devinit tg3_init_one(struct pci_dev *pdev, 
	 * checksumming.

	 */

	if ((tp->tg3_flags & TG3_FLAG_BROKEN_CHECKSUMS) == 0) {

		dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;

		if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5755 ||

		    GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5787)

			dev->features |= NETIF_F_HW_CSUM;

		else

			dev->features |= NETIF_F_IP_CSUM;

		dev->features |= NETIF_F_SG;

			dev->features |= NETIF_F_IPV6_CSUM;



		tp->tg3_flags |= TG3_FLAG_RX_CHECKSUMS;

	} else

		tp->tg3_flags &= ~TG3_FLAG_RX_CHECKSUMS;

include/linux/netdevice.h

+6 −2
Original line number Diff line number Diff line
@@ -314,9 +314,10 @@ struct net_device 
	/* Net device features */

	unsigned long		features;

#define NETIF_F_SG		1	/* Scatter/gather IO. */

#define NETIF_F_IP_CSUM		2	/* Can checksum only TCP/UDP over IPv4. */

#define NETIF_F_IP_CSUM		2	/* Can checksum TCP/UDP over IPv4. */

#define NETIF_F_NO_CSUM		4	/* Does not require checksum. F.e. loopack. */

#define NETIF_F_HW_CSUM		8	/* Can checksum all the packets. */

#define NETIF_F_IPV6_CSUM	16	/* Can checksum TCP/UDP over IPV6 */

#define NETIF_F_HIGHDMA		32	/* Can DMA to high memory. */

#define NETIF_F_FRAGLIST	64	/* Scatter/gather IO. */

#define NETIF_F_HW_VLAN_TX	128	/* Transmit VLAN hw acceleration */
@@ -338,8 +339,11 @@ struct net_device 
	/* List of features with software fallbacks. */

#define NETIF_F_GSO_SOFTWARE	(NETIF_F_TSO | NETIF_F_TSO_ECN | NETIF_F_TSO6)





#define NETIF_F_GEN_CSUM	(NETIF_F_NO_CSUM | NETIF_F_HW_CSUM)

#define NETIF_F_ALL_CSUM	(NETIF_F_IP_CSUM | NETIF_F_GEN_CSUM)

#define NETIF_F_V4_CSUM		(NETIF_F_GEN_CSUM | NETIF_F_IP_CSUM)

#define NETIF_F_V6_CSUM		(NETIF_F_GEN_CSUM | NETIF_F_IPV6_CSUM)

#define NETIF_F_ALL_CSUM	(NETIF_F_V4_CSUM | NETIF_F_V6_CSUM)



	struct net_device	*next_sched;

net/bridge/br_if.c

+9 −1
Original line number Diff line number Diff line
@@ -368,10 +368,18 @@ void br_features_recompute(struct net_bridge *br) 
	list_for_each_entry(p, &br->port_list, list) {

		unsigned long feature = p->dev->features;



		/* if device needs checksumming, downgrade to hw checksumming */

		if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM))

			checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;



		/* if device can't do all checksum, downgrade to ipv4/ipv6 */

		if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM))

			checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM;

			checksum ^= NETIF_F_HW_CSUM

				| NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;



		if (checksum & NETIF_F_IPV6_CSUM && !(feature & NETIF_F_IPV6_CSUM))

			checksum &= ~NETIF_F_IPV6_CSUM;



		if (!(feature & NETIF_F_IP_CSUM))

			checksum = 0;

net/core/dev.c

+21 −3
Original line number Diff line number Diff line
@@ -1509,9 +1509,11 @@ int dev_queue_xmit(struct sk_buff *skb) 
		skb_set_transport_header(skb, skb->csum_start -

					      skb_headroom(skb));



		if (!(dev->features & NETIF_F_GEN_CSUM) &&

		    (!(dev->features & NETIF_F_IP_CSUM) ||

		     skb->protocol != htons(ETH_P_IP)))

		if (!(dev->features & NETIF_F_GEN_CSUM)

		    || ((dev->features & NETIF_F_IP_CSUM)

			&& skb->protocol == htons(ETH_P_IP))

		    || ((dev->features & NETIF_F_IPV6_CSUM)

			&& skb->protocol == htons(ETH_P_IPV6)))

			if (skb_checksum_help(skb))

				goto out_kfree_skb;

	}
@@ -3107,6 +3109,22 @@ int register_netdevice(struct net_device *dev) 
		}

	}



	/* Fix illegal checksum combinations */

	if ((dev->features & NETIF_F_HW_CSUM) &&

	    (dev->features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {

		printk(KERN_NOTICE "%s: mixed HW and IP checksum settings.\n",

		       dev->name);

		dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);

	}



	if ((dev->features & NETIF_F_NO_CSUM) &&

	    (dev->features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {

		printk(KERN_NOTICE "%s: mixed no checksumming and other settings.\n",

		       dev->name);

		dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);

	}





	/* Fix illegal SG+CSUM combinations. */

	if ((dev->features & NETIF_F_SG) &&

	    !(dev->features & NETIF_F_ALL_CSUM)) {

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