X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=datapath%2Factions.c;h=4fc0a4a4405929c2a7c6acb30e4499a75dfa7a5d;hb=7dab847a19503f537c57c2215748f0b50b94f51e;hp=53bf3efd3e8dce99adcf8622345844ab86fbcc28;hpb=00ba5f3b155003640875b780d0f4ccd9274158c6;p=openvswitch

diff --git a/datapath/actions.c b/datapath/actions.c
index 53bf3efd..4fc0a4a4 100644
--- a/datapath/actions.c
+++ b/datapath/actions.c
@@ -213,10 +213,43 @@ static void update_csum(__sum16 *sum, struct sk_buff *skb,
 			__be32 from, __be32 to, int pseudohdr)
 {
 	__be32 diff[] = { ~from, to };
-	if (skb->ip_summed != CHECKSUM_PARTIAL) {
+
+/* On older kernels, CHECKSUM_PARTIAL and CHECKSUM_COMPLETE are both defined
+ * as CHECKSUM_HW.  However, we can make some inferences so that we can update
+ * the checksums appropriately. */
+	enum {
+		CSUM_PARTIAL,	/* Partial checksum, skb->csum undefined. */
+		CSUM_PACKET,	/* In-packet checksum, skb->csum undefined. */
+		CSUM_COMPLETE,	/* In-packet checksum, skb->csum valid. */
+	} csum_type;
+
+	csum_type = CSUM_PACKET;
+#ifndef CHECKSUM_HW
+	/* Newer kernel, just map between kernel types and ours. */
+	if (skb->ip_summed == CHECKSUM_PARTIAL)
+		csum_type = CSUM_PARTIAL;
+	else if (skb->ip_summed == CHECKSUM_COMPLETE)
+		csum_type = CSUM_COMPLETE;
+#else
+	/* In theory this could be either CHECKSUM_PARTIAL or CHECKSUM_COMPLETE.
+	 * However, we should only get CHECKSUM_PARTIAL packets from Xen, which
+	 * uses some special fields to represent this (see below).  Since we
+	 * can only make one type work, pick the one that actually happens in
+	 * practice. */
+	if (skb->ip_summed == CHECKSUM_HW)
+		csum_type = CSUM_COMPLETE;
+#endif
+#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID)
+	/* Xen has a special way of representing CHECKSUM_PARTIAL on older
+	 * kernels. */
+	if (skb->proto_csum_blank)
+		csum_type = CSUM_PARTIAL;
+#endif
+
+	if (csum_type != CSUM_PARTIAL) {
 		*sum = csum_fold(csum_partial((char *)diff, sizeof(diff),
 				~csum_unfold(*sum)));
-		if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+		if (csum_type == CSUM_COMPLETE && pseudohdr)
 			skb->csum = ~csum_partial((char *)diff, sizeof(diff),
 						~skb->csum);
 	} else if (pseudohdr)
@@ -367,6 +400,28 @@ output_control(struct datapath *dp, struct sk_buff *skb, u32 arg, gfp_t gfp)
 	return dp_output_control(dp, skb, _ODPL_ACTION_NR, arg);
 }
 
+/* Send a copy of this packet up to the sFlow agent, along with extra
+ * information about what happened to it. */
+static void sflow_sample(struct datapath *dp, struct sk_buff *skb,
+			 const union odp_action *a, int n_actions,
+			 gfp_t gfp, struct net_bridge_port *nbp)
+{
+	struct odp_sflow_sample_header *hdr;
+	unsigned int actlen = n_actions * sizeof(union odp_action);
+	unsigned int hdrlen = sizeof(struct odp_sflow_sample_header);
+	struct sk_buff *nskb;
+
+	nskb = skb_copy_expand(skb, actlen + hdrlen, 0, gfp);
+	if (!nskb)
+		return;
+
+	memcpy(__skb_push(nskb, actlen), a, actlen);
+	hdr = (struct odp_sflow_sample_header*)__skb_push(nskb, hdrlen);
+	hdr->n_actions = n_actions;
+	hdr->sample_pool = atomic_read(&nbp->sflow_pool);
+	dp_output_control(dp, nskb, _ODPL_SFLOW_NR, 0);
+}
+
 /* Execute a list of actions against 'skb'. */
 int execute_actions(struct datapath *dp, struct sk_buff *skb,
 		    struct odp_flow_key *key,
@@ -379,6 +434,17 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 	 * is slightly obscure just to avoid that. */
 	int prev_port = -1;
 	int err;
+
+	if (dp->sflow_probability) {
+		struct net_bridge_port *p = skb->dev->br_port;
+		if (p) {
+			atomic_inc(&p->sflow_pool);
+			if (dp->sflow_probability == UINT_MAX ||
+			    net_random() < dp->sflow_probability)
+				sflow_sample(dp, skb, a, n_actions, gfp, p);
+		}
+	}
+
 	for (; n_actions > 0; a++, n_actions--) {
 		WARN_ON_ONCE(skb_shared(skb));
 		if (prev_port != -1) {