1 files changed, 169 insertions, 19 deletions

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index f35eccaa855..546d2d439dd 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -14,6 +14,17 @@
 #include <net/udp.h>
 #include <net/protocol.h>
 
+static DEFINE_SPINLOCK(udp_offload_lock);
+static struct udp_offload_priv __rcu *udp_offload_base __read_mostly;
+
+#define udp_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&udp_offload_lock))
+
+struct udp_offload_priv {
+	struct udp_offload	*offload;
+	struct rcu_head		rcu;
+	struct udp_offload_priv __rcu *next;
+};
+
 static int udp4_ufo_send_check(struct sk_buff *skb)
 {
 	if (!pskb_may_pull(skb, sizeof(struct udphdr)))
@@ -41,6 +52,15 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
 {
 	struct sk_buff *segs = ERR_PTR(-EINVAL);
 	unsigned int mss;
+	int offset;
+	__wsum csum;
+
+	if (skb->encapsulation &&
+	    (skb_shinfo(skb)->gso_type &
+	     (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM))) {
+		segs = skb_udp_tunnel_segment(skb, features);
+		goto out;
+	}
 
 	mss = skb_shinfo(skb)->gso_size;
 	if (unlikely(skb->len <= mss))
@@ -52,7 +72,10 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
 
 		if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY |
 				      SKB_GSO_UDP_TUNNEL |
-				      SKB_GSO_GRE | SKB_GSO_MPLS) ||
+				      SKB_GSO_UDP_TUNNEL_CSUM |
+				      SKB_GSO_IPIP |
+				      SKB_GSO_GRE | SKB_GSO_GRE_CSUM |
+				      SKB_GSO_MPLS) ||
 			     !(type & (SKB_GSO_UDP))))
 			goto out;
 
@@ -62,35 +85,162 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
 		goto out;
 	}
 
+	/* Do software UFO. Complete and fill in the UDP checksum as
+	 * HW cannot do checksum of UDP packets sent as multiple
+	 * IP fragments.
+	 */
+	offset = skb_checksum_start_offset(skb);
+	csum = skb_checksum(skb, offset, skb->len - offset, 0);
+	offset += skb->csum_offset;
+	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
+	skb->ip_summed = CHECKSUM_NONE;
+
 	/* Fragment the skb. IP headers of the fragments are updated in
 	 * inet_gso_segment()
 	 */
-	if (skb->encapsulation && skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL)
-		segs = skb_udp_tunnel_segment(skb, features);
-	else {
-		int offset;
-		__wsum csum;
-
-		/* Do software UFO. Complete and fill in the UDP checksum as
-		 * HW cannot do checksum of UDP packets sent as multiple
-		 * IP fragments.
-		 */
-		offset = skb_checksum_start_offset(skb);
-		csum = skb_checksum(skb, offset, skb->len - offset, 0);
-		offset += skb->csum_offset;
-		*(__sum16 *)(skb->data + offset) = csum_fold(csum);
-		skb->ip_summed = CHECKSUM_NONE;
-
-		segs = skb_segment(skb, features);
-	}
+	segs = skb_segment(skb, features);
 out:
 	return segs;
 }
 
+int udp_add_offload(struct udp_offload *uo)
+{
+	struct udp_offload_priv *new_offload = kzalloc(sizeof(*new_offload), GFP_ATOMIC);
+
+	if (!new_offload)
+		return -ENOMEM;
+
+	new_offload->offload = uo;
+
+	spin_lock(&udp_offload_lock);
+	new_offload->next = udp_offload_base;
+	rcu_assign_pointer(udp_offload_base, new_offload);
+	spin_unlock(&udp_offload_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(udp_add_offload);
+
+static void udp_offload_free_routine(struct rcu_head *head)
+{
+	struct udp_offload_priv *ou_priv = container_of(head, struct udp_offload_priv, rcu);
+	kfree(ou_priv);
+}
+
+void udp_del_offload(struct udp_offload *uo)
+{
+	struct udp_offload_priv __rcu **head = &udp_offload_base;
+	struct udp_offload_priv *uo_priv;
+
+	spin_lock(&udp_offload_lock);
+
+	uo_priv = udp_deref_protected(*head);
+	for (; uo_priv != NULL;
+	     uo_priv = udp_deref_protected(*head)) {
+		if (uo_priv->offload == uo) {
+			rcu_assign_pointer(*head,
+					   udp_deref_protected(uo_priv->next));
+			goto unlock;
+		}
+		head = &uo_priv->next;
+	}
+	pr_warn("udp_del_offload: didn't find offload for port %d\n", ntohs(uo->port));
+unlock:
+	spin_unlock(&udp_offload_lock);
+	if (uo_priv != NULL)
+		call_rcu(&uo_priv->rcu, udp_offload_free_routine);
+}
+EXPORT_SYMBOL(udp_del_offload);
+
+static struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb)
+{
+	struct udp_offload_priv *uo_priv;
+	struct sk_buff *p, **pp = NULL;
+	struct udphdr *uh, *uh2;
+	unsigned int hlen, off;
+	int flush = 1;
+
+	if (NAPI_GRO_CB(skb)->udp_mark ||
+	    (!skb->encapsulation && skb->ip_summed != CHECKSUM_COMPLETE))
+		goto out;
+
+	/* mark that this skb passed once through the udp gro layer */
+	NAPI_GRO_CB(skb)->udp_mark = 1;
+
+	off  = skb_gro_offset(skb);
+	hlen = off + sizeof(*uh);
+	uh   = skb_gro_header_fast(skb, off);
+	if (skb_gro_header_hard(skb, hlen)) {
+		uh = skb_gro_header_slow(skb, hlen, off);
+		if (unlikely(!uh))
+			goto out;
+	}
+
+	rcu_read_lock();
+	uo_priv = rcu_dereference(udp_offload_base);
+	for (; uo_priv != NULL; uo_priv = rcu_dereference(uo_priv->next)) {
+		if (uo_priv->offload->port == uh->dest &&
+		    uo_priv->offload->callbacks.gro_receive)
+			goto unflush;
+	}
+	goto out_unlock;
+
+unflush:
+	flush = 0;
+
+	for (p = *head; p; p = p->next) {
+		if (!NAPI_GRO_CB(p)->same_flow)
+			continue;
+
+		uh2 = (struct udphdr   *)(p->data + off);
+		if ((*(u32 *)&uh->source != *(u32 *)&uh2->source)) {
+			NAPI_GRO_CB(p)->same_flow = 0;
+			continue;
+		}
+	}
+
+	skb_gro_pull(skb, sizeof(struct udphdr)); /* pull encapsulating udp header */
+	skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr));
+	pp = uo_priv->offload->callbacks.gro_receive(head, skb);
+
+out_unlock:
+	rcu_read_unlock();
+out:
+	NAPI_GRO_CB(skb)->flush |= flush;
+	return pp;
+}
+
+static int udp_gro_complete(struct sk_buff *skb, int nhoff)
+{
+	struct udp_offload_priv *uo_priv;
+	__be16 newlen = htons(skb->len - nhoff);
+	struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
+	int err = -ENOSYS;
+
+	uh->len = newlen;
+
+	rcu_read_lock();
+
+	uo_priv = rcu_dereference(udp_offload_base);
+	for (; uo_priv != NULL; uo_priv = rcu_dereference(uo_priv->next)) {
+		if (uo_priv->offload->port == uh->dest &&
+		    uo_priv->offload->callbacks.gro_complete)
+			break;
+	}
+
+	if (uo_priv != NULL)
+		err = uo_priv->offload->callbacks.gro_complete(skb, nhoff + sizeof(struct udphdr));
+
+	rcu_read_unlock();
+	return err;
+}
+
 static const struct net_offload udpv4_offload = {
 	.callbacks = {
 		.gso_send_check = udp4_ufo_send_check,
 		.gso_segment = udp4_ufo_fragment,
+		.gro_receive  =	udp_gro_receive,
+		.gro_complete =	udp_gro_complete,
 	},
 };