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authorTom Herbert <therbert@google.com>2014-11-04 09:06:52 -0800
committerDavid S. Miller <davem@davemloft.net>2014-11-05 16:30:03 -0500
commit4bcb877d257c87298aedead1ffeaba0d5df1991d (patch)
tree00b616716253b6bed2510505e38f345b1a165efa /net/ipv4/udp_offload.c
parent63487babf08d6d67483c67ed21d8cea6674a44ec (diff)
downloadlinux-4bcb877d257c87298aedead1ffeaba0d5df1991d.tar.bz2
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: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/udp_offload.c')
-rw-r--r--net/ipv4/udp_offload.c52
1 files changed, 36 insertions, 16 deletions
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 6480cea7aa53..a774711a88b9 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -29,7 +29,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
netdev_features_t features,
struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb,
netdev_features_t features),
- __be16 new_protocol)
+ __be16 new_protocol, bool is_ipv6)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
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;
int udp_offset, outer_hlen;
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;
@@ -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->mac_len = skb_inner_network_offset(skb);
skb->protocol = new_protocol;
+ skb->encap_hdr_csum = need_csum;
- need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM);
- if (need_csum)
- skb->encap_hdr_csum = 1;
+ /* Try to offload checksum if possible */
+ offload_csum = !!(need_csum &&
+ (skb->dev->features &
+ (is_ipv6 ? NETIF_F_V6_CSUM : NETIF_F_V4_CSUM)));
/* segment inner packet. */
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 {
struct udphdr *uh;
int len;
-
- skb_reset_inner_headers(skb);
- skb->encapsulation = 1;
+ __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->encapsulation = 1;
+ }
skb->mac_len = mac_len;
+ skb->protocol = protocol;
skb_push(skb, outer_hlen);
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->len = htons(len);
- if (need_csum) {
- __be32 delta = htonl(oldlen + len);
+ if (!need_csum)
+ continue;
+
+ delta = htonl(oldlen + len);
+
+ uh->check = ~csum_fold((__force __wsum)
+ ((__force u32)uh->check +
+ (__force u32)delta));
- uh->check = ~csum_fold((__force __wsum)
- ((__force u32)uh->check +
- (__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);
if (uh->check == 0)
uh->check = CSUM_MANGLED_0;
}
-
- skb->protocol = protocol;
} while ((skb = skb->next));
out:
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,
- protocol);
+ protocol, is_ipv6);
out_unlock:
rcu_read_unlock();