Commit 4bcb877d authored by Tom Herbert's avatar Tom Herbert Committed by David S. Miller
Browse files

udp: Offload outer UDP tunnel csum if available 



In __skb_udp_tunnel_segment if outer UDP checksums are enabled and
ip_summed is not already CHECKSUM_PARTIAL, set up checksum offload
if device features allow it.

Signed-off-by: default avatarTom Herbert <therbert@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 63487bab

net/ipv4/udp_offload.c

+36 −16
Original line number Original line Diff line number Diff line
@@ -29,7 +29,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, 
	netdev_features_t features,

	netdev_features_t features,

	struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb,

	struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb,

					     netdev_features_t features),

					     netdev_features_t features),

	__be16 new_protocol)

	__be16 new_protocol, bool is_ipv6)

{

{

	struct sk_buff *segs = ERR_PTR(-EINVAL);

	struct sk_buff *segs = ERR_PTR(-EINVAL);

	u16 mac_offset = skb->mac_header;

	u16 mac_offset = skb->mac_header;
@@ -39,7 +39,9 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, 
	netdev_features_t enc_features;

	netdev_features_t enc_features;

	int udp_offset, outer_hlen;

	int udp_offset, outer_hlen;

	unsigned int oldlen;

	unsigned int oldlen;

	bool need_csum;

	bool need_csum = !!(skb_shinfo(skb)->gso_type &

			    SKB_GSO_UDP_TUNNEL_CSUM);

	bool offload_csum = false, dont_encap = need_csum;





	oldlen = (u16)~skb->len;

	oldlen = (u16)~skb->len;
@@ -52,10 +54,12 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, 
	skb_set_network_header(skb, skb_inner_network_offset(skb));

	skb_set_network_header(skb, skb_inner_network_offset(skb));

	skb->mac_len = skb_inner_network_offset(skb);

	skb->mac_len = skb_inner_network_offset(skb);

	skb->protocol = new_protocol;

	skb->protocol = new_protocol;

	skb->encap_hdr_csum = need_csum;





	need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM);

	/* Try to offload checksum if possible */

	if (need_csum)

	offload_csum = !!(need_csum &&

		skb->encap_hdr_csum = 1;

			  (skb->dev->features &

			   (is_ipv6 ? NETIF_F_V6_CSUM : NETIF_F_V4_CSUM)));





	/* segment inner packet. */

	/* segment inner packet. */

	enc_features = skb->dev->hw_enc_features & features;

	enc_features = skb->dev->hw_enc_features & features;
@@ -72,11 +76,21 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, 
	do {

	do {

		struct udphdr *uh;

		struct udphdr *uh;

		int len;

		int len;

		__be32 delta;





		if (dont_encap) {

			skb->encapsulation = 0;

			skb->ip_summed = CHECKSUM_NONE;

		} else {

			/* Only set up inner headers if we might be offloading

			 * inner checksum.

			 */

			skb_reset_inner_headers(skb);

			skb_reset_inner_headers(skb);

			skb->encapsulation = 1;

			skb->encapsulation = 1;

		}





		skb->mac_len = mac_len;

		skb->mac_len = mac_len;

		skb->protocol = protocol;





		skb_push(skb, outer_hlen);

		skb_push(skb, outer_hlen);

		skb_reset_mac_header(skb);

		skb_reset_mac_header(skb);
@@ -86,19 +100,25 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, 
		uh = udp_hdr(skb);

		uh = udp_hdr(skb);

		uh->len = htons(len);

		uh->len = htons(len);





		if (need_csum) {

		if (!need_csum)

			__be32 delta = htonl(oldlen + len);

			continue;



		delta = htonl(oldlen + len);





		uh->check = ~csum_fold((__force __wsum)

		uh->check = ~csum_fold((__force __wsum)

				       ((__force u32)uh->check +

				       ((__force u32)uh->check +

					(__force u32)delta));

					(__force u32)delta));



		if (offload_csum) {

			skb->ip_summed = CHECKSUM_PARTIAL;

			skb->csum_start = skb_transport_header(skb) - skb->head;

			skb->csum_offset = offsetof(struct udphdr, check);

		} else {

			uh->check = gso_make_checksum(skb, ~uh->check);

			uh->check = gso_make_checksum(skb, ~uh->check);





			if (uh->check == 0)

			if (uh->check == 0)

				uh->check = CSUM_MANGLED_0;

				uh->check = CSUM_MANGLED_0;

		}

		}



		skb->protocol = protocol;

	} while ((skb = skb->next));

	} while ((skb = skb->next));

out:

out:

	return segs;

	return segs;
@@ -134,7 +154,7 @@ struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, 
	}

	}





	segs = __skb_udp_tunnel_segment(skb, features, gso_inner_segment,

	segs = __skb_udp_tunnel_segment(skb, features, gso_inner_segment,

					protocol);

					protocol, is_ipv6);





out_unlock:

out_unlock:

	rcu_read_unlock();

	rcu_read_unlock();