[NET]: Add software TSOv4
This patch adds the GSO implementation for IPv4 TCP.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 0a27745..461216b 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -68,6 +68,7 @@
*/
#include <linux/config.h>
+#include <linux/err.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
@@ -1096,6 +1097,54 @@
EXPORT_SYMBOL(inet_sk_rebuild_header);
+static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int sg)
+{
+ struct sk_buff *segs = ERR_PTR(-EINVAL);
+ struct iphdr *iph;
+ struct net_protocol *ops;
+ int proto;
+ int ihl;
+ int id;
+
+ if (!pskb_may_pull(skb, sizeof(*iph)))
+ goto out;
+
+ iph = skb->nh.iph;
+ ihl = iph->ihl * 4;
+ if (ihl < sizeof(*iph))
+ goto out;
+
+ if (!pskb_may_pull(skb, ihl))
+ goto out;
+
+ skb->h.raw = __skb_pull(skb, ihl);
+ iph = skb->nh.iph;
+ id = ntohs(iph->id);
+ proto = iph->protocol & (MAX_INET_PROTOS - 1);
+ segs = ERR_PTR(-EPROTONOSUPPORT);
+
+ rcu_read_lock();
+ ops = rcu_dereference(inet_protos[proto]);
+ if (ops && ops->gso_segment)
+ segs = ops->gso_segment(skb, sg);
+ rcu_read_unlock();
+
+ if (IS_ERR(segs))
+ goto out;
+
+ skb = segs;
+ do {
+ iph = skb->nh.iph;
+ iph->id = htons(id++);
+ iph->tot_len = htons(skb->len - skb->mac_len);
+ iph->check = 0;
+ iph->check = ip_fast_csum(skb->nh.raw, iph->ihl);
+ } while ((skb = skb->next));
+
+out:
+ return segs;
+}
+
#ifdef CONFIG_IP_MULTICAST
static struct net_protocol igmp_protocol = {
.handler = igmp_rcv,
@@ -1105,6 +1154,7 @@
static struct net_protocol tcp_protocol = {
.handler = tcp_v4_rcv,
.err_handler = tcp_v4_err,
+ .gso_segment = tcp_tso_segment,
.no_policy = 1,
};
@@ -1150,6 +1200,7 @@
static struct packet_type ip_packet_type = {
.type = __constant_htons(ETH_P_IP),
.func = ip_rcv,
+ .gso_segment = inet_gso_segment,
};
static int __init inet_init(void)