fou: Add GRO support

Implement fou_gro_receive and fou_gro_complete, and populate these
in the correponsing udp_offloads for the socket. Added ipproto to
udp_offloads and pass this from UDP to the fou GRO routine in proto
field of napi_gro_cb structure.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 89 insertions, 0 deletions

diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index d44f97b79418..dced89fbe480 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -8,6 +8,7 @@
 #include <linux/kernel.h>
 #include <net/genetlink.h>
 #include <net/ip.h>
+#include <net/protocol.h>
 #include <net/udp.h>
 #include <net/udp_tunnel.h>
 #include <net/xfrm.h>
@@ -21,6 +22,7 @@ struct fou {
         struct socket *sock;
         u8 protocol;
         u16 port;
+        struct udp_offload udp_offloads;
         struct list_head list;
 };
 
@@ -62,6 +64,69 @@ static int fou_udp_recv(struct sock *sk, struct sk_buff *skb)
                                           sizeof(struct udphdr));
 }
 
+static struct sk_buff **fou_gro_receive(struct sk_buff **head,
+                                        struct sk_buff *skb,
+                                        const struct net_offload **offloads)
+{
+        const struct net_offload *ops;
+        struct sk_buff **pp = NULL;
+        u8 proto = NAPI_GRO_CB(skb)->proto;
+
+        rcu_read_lock();
+        ops = rcu_dereference(offloads[proto]);
+        if (!ops || !ops->callbacks.gro_receive)
+                goto out_unlock;
+
+        pp = ops->callbacks.gro_receive(head, skb);
+
+out_unlock:
+        rcu_read_unlock();
+
+        return pp;
+}
+
+static int fou_gro_complete(struct sk_buff *skb, int nhoff,
+                            const struct net_offload **offloads)
+{
+        const struct net_offload *ops;
+        u8 proto = NAPI_GRO_CB(skb)->proto;
+        int err = -ENOSYS;
+
+        rcu_read_lock();
+        ops = rcu_dereference(offloads[proto]);
+        if (WARN_ON(!ops || !ops->callbacks.gro_complete))
+                goto out_unlock;
+
+        err = ops->callbacks.gro_complete(skb, nhoff);
+
+out_unlock:
+        rcu_read_unlock();
+
+        return err;
+}
+
+static struct sk_buff **fou4_gro_receive(struct sk_buff **head,
+                                         struct sk_buff *skb)
+{
+        return fou_gro_receive(head, skb, inet_offloads);
+}
+
+static int fou4_gro_complete(struct sk_buff *skb, int nhoff)
+{
+        return fou_gro_complete(skb, nhoff, inet_offloads);
+}
+
+static struct sk_buff **fou6_gro_receive(struct sk_buff **head,
+                                         struct sk_buff *skb)
+{
+        return fou_gro_receive(head, skb, inet6_offloads);
+}
+
+static int fou6_gro_complete(struct sk_buff *skb, int nhoff)
+{
+        return fou_gro_complete(skb, nhoff, inet6_offloads);
+}
+
 static int fou_add_to_port_list(struct fou *fou)
 {
         struct fou *fout;
@@ -134,6 +199,29 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
 
         sk->sk_allocation = GFP_ATOMIC;
 
+        switch (cfg->udp_config.family) {
+        case AF_INET:
+                fou->udp_offloads.callbacks.gro_receive = fou4_gro_receive;
+                fou->udp_offloads.callbacks.gro_complete = fou4_gro_complete;
+                break;
+        case AF_INET6:
+                fou->udp_offloads.callbacks.gro_receive = fou6_gro_receive;
+                fou->udp_offloads.callbacks.gro_complete = fou6_gro_complete;
+                break;
+        default:
+                err = -EPFNOSUPPORT;
+                goto error;
+        }
+
+        fou->udp_offloads.port = cfg->udp_config.local_udp_port;
+        fou->udp_offloads.ipproto = cfg->protocol;
+
+        if (cfg->udp_config.family == AF_INET) {
+                err = udp_add_offload(&fou->udp_offloads);
+                if (err)
+                        goto error;
+        }
+
         err = fou_add_to_port_list(fou);
         if (err)
                 goto error;
@@ -160,6 +248,7 @@ static int fou_destroy(struct net *net, struct fou_cfg *cfg)
         spin_lock(&fou_lock);
         list_for_each_entry(fou, &fou_list, list) {
                 if (fou->port == port) {
+                        udp_del_offload(&fou->udp_offloads);
                         fou_release(fou);
                         err = 0;
                         break;