1 files changed, 150 insertions, 145 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index ab9a16530c3..3c6a967e583 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2485,52 +2485,6 @@ static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
 	return 0;
 }
 
-struct dev_gso_cb {
-	void (*destructor)(struct sk_buff *skb);
-};
-
-#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
-
-static void dev_gso_skb_destructor(struct sk_buff *skb)
-{
-	struct dev_gso_cb *cb;
-
-	kfree_skb_list(skb->next);
-	skb->next = NULL;
-
-	cb = DEV_GSO_CB(skb);
-	if (cb->destructor)
-		cb->destructor(skb);
-}
-
-/**
- *	dev_gso_segment - Perform emulated hardware segmentation on skb.
- *	@skb: buffer to segment
- *	@features: device features as applicable to this skb
- *
- *	This function segments the given skb and stores the list of segments
- *	in skb->next.
- */
-static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
-{
-	struct sk_buff *segs;
-
-	segs = skb_gso_segment(skb, features);
-
-	/* Verifying header integrity only. */
-	if (!segs)
-		return 0;
-
-	if (IS_ERR(segs))
-		return PTR_ERR(segs);
-
-	skb->next = segs;
-	DEV_GSO_CB(skb)->destructor = skb->destructor;
-	skb->destructor = dev_gso_skb_destructor;
-
-	return 0;
-}
-
 /* If MPLS offload request, verify we are testing hardware MPLS features
  * instead of standard features for the netdev.
  */
@@ -2605,119 +2559,125 @@ netdev_features_t netif_skb_features(struct sk_buff *skb)
 }
 EXPORT_SYMBOL(netif_skb_features);
 
-int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
-			struct netdev_queue *txq)
+static int xmit_one(struct sk_buff *skb, struct net_device *dev,
+		    struct netdev_queue *txq, bool more)
 {
-	const struct net_device_ops *ops = dev->netdev_ops;
+	unsigned int len;
+	int rc;
+
+	if (!list_empty(&ptype_all))
+		dev_queue_xmit_nit(skb, dev);
+
+	len = skb->len;
+	trace_net_dev_start_xmit(skb, dev);
+	rc = netdev_start_xmit(skb, dev, txq, more);
+	trace_net_dev_xmit(skb, rc, dev, len);
+
+	return rc;
+}
+
+struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
+				    struct netdev_queue *txq, int *ret)
+{
+	struct sk_buff *skb = first;
 	int rc = NETDEV_TX_OK;
-	unsigned int skb_len;
 
-	if (likely(!skb->next)) {
-		netdev_features_t features;
+	while (skb) {
+		struct sk_buff *next = skb->next;
 
-		/*
-		 * If device doesn't need skb->dst, release it right now while
-		 * its hot in this cpu cache
-		 */
-		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
-			skb_dst_drop(skb);
+		skb->next = NULL;
+		rc = xmit_one(skb, dev, txq, next != NULL);
+		if (unlikely(!dev_xmit_complete(rc))) {
+			skb->next = next;
+			goto out;
+		}
 
-		features = netif_skb_features(skb);
+		skb = next;
+		if (netif_xmit_stopped(txq) && skb) {
+			rc = NETDEV_TX_BUSY;
+			break;
+		}
+	}
 
-		if (vlan_tx_tag_present(skb) &&
-		    !vlan_hw_offload_capable(features, skb->vlan_proto)) {
-			skb = __vlan_put_tag(skb, skb->vlan_proto,
-					     vlan_tx_tag_get(skb));
-			if (unlikely(!skb))
-				goto out;
+out:
+	*ret = rc;
+	return skb;
+}
 
+struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, netdev_features_t features)
+{
+	if (vlan_tx_tag_present(skb) &&
+	    !vlan_hw_offload_capable(features, skb->vlan_proto)) {
+		skb = __vlan_put_tag(skb, skb->vlan_proto,
+				     vlan_tx_tag_get(skb));
+		if (skb)
 			skb->vlan_tci = 0;
-		}
+	}
+	return skb;
+}
 
-		/* If encapsulation offload request, verify we are testing
-		 * hardware encapsulation features instead of standard
-		 * features for the netdev
-		 */
-		if (skb->encapsulation)
-			features &= dev->hw_enc_features;
+struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
+{
+	netdev_features_t features;
 
-		if (netif_needs_gso(skb, features)) {
-			if (unlikely(dev_gso_segment(skb, features)))
-				goto out_kfree_skb;
-			if (skb->next)
-				goto gso;
-		} else {
-			if (skb_needs_linearize(skb, features) &&
-			    __skb_linearize(skb))
-				goto out_kfree_skb;
+	if (skb->next)
+		return skb;
 
-			/* If packet is not checksummed and device does not
-			 * support checksumming for this protocol, complete
-			 * checksumming here.
-			 */
-			if (skb->ip_summed == CHECKSUM_PARTIAL) {
-				if (skb->encapsulation)
-					skb_set_inner_transport_header(skb,
-						skb_checksum_start_offset(skb));
-				else
-					skb_set_transport_header(skb,
-						skb_checksum_start_offset(skb));
-				if (!(features & NETIF_F_ALL_CSUM) &&
-				     skb_checksum_help(skb))
-					goto out_kfree_skb;
-			}
-		}
+	/* If device doesn't need skb->dst, release it right now while
+	 * its hot in this cpu cache
+	 */
+	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
+		skb_dst_drop(skb);
 
-		if (!list_empty(&ptype_all))
-			dev_queue_xmit_nit(skb, dev);
+	features = netif_skb_features(skb);
+	skb = validate_xmit_vlan(skb, features);
+	if (unlikely(!skb))
+		goto out_null;
 
-		skb_len = skb->len;
-		trace_net_dev_start_xmit(skb, dev);
-		rc = ops->ndo_start_xmit(skb, dev);
-		trace_net_dev_xmit(skb, rc, dev, skb_len);
-		if (rc == NETDEV_TX_OK)
-			txq_trans_update(txq);
-		return rc;
-	}
+	/* If encapsulation offload request, verify we are testing
+	 * hardware encapsulation features instead of standard
+	 * features for the netdev
+	 */
+	if (skb->encapsulation)
+		features &= dev->hw_enc_features;
 
-gso:
-	do {
-		struct sk_buff *nskb = skb->next;
+	if (netif_needs_gso(skb, features)) {
+		struct sk_buff *segs;
 
-		skb->next = nskb->next;
-		nskb->next = NULL;
+		segs = skb_gso_segment(skb, features);
+		kfree_skb(skb);
+		if (IS_ERR(segs))
+			segs = NULL;
+		skb = segs;
+	} else {
+		if (skb_needs_linearize(skb, features) &&
+		    __skb_linearize(skb))
+			goto out_kfree_skb;
 
-		if (!list_empty(&ptype_all))
-			dev_queue_xmit_nit(nskb, dev);
-
-		skb_len = nskb->len;
-		trace_net_dev_start_xmit(nskb, dev);
-		rc = ops->ndo_start_xmit(nskb, dev);
-		trace_net_dev_xmit(nskb, rc, dev, skb_len);
-		if (unlikely(rc != NETDEV_TX_OK)) {
-			if (rc & ~NETDEV_TX_MASK)
-				goto out_kfree_gso_skb;
-			nskb->next = skb->next;
-			skb->next = nskb;
-			return rc;
+		/* If packet is not checksummed and device does not
+		 * support checksumming for this protocol, complete
+		 * checksumming here.
+		 */
+		if (skb->ip_summed == CHECKSUM_PARTIAL) {
+			if (skb->encapsulation)
+				skb_set_inner_transport_header(skb,
+							       skb_checksum_start_offset(skb));
+			else
+				skb_set_transport_header(skb,
+							 skb_checksum_start_offset(skb));
+			if (!(features & NETIF_F_ALL_CSUM) &&
+			    skb_checksum_help(skb))
+				goto out_kfree_skb;
 		}
-		txq_trans_update(txq);
-		if (unlikely(netif_xmit_stopped(txq) && skb->next))
-			return NETDEV_TX_BUSY;
-	} while (skb->next);
-
-out_kfree_gso_skb:
-	if (likely(skb->next == NULL)) {
-		skb->destructor = DEV_GSO_CB(skb)->destructor;
-		consume_skb(skb);
-		return rc;
 	}
+
+	return skb;
+
 out_kfree_skb:
 	kfree_skb(skb);
-out:
-	return rc;
+out_null:
+	return NULL;
 }
-EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
 
 static void qdisc_pkt_len_init(struct sk_buff *skb)
 {
@@ -2785,7 +2745,8 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 
 		qdisc_bstats_update(q, skb);
 
-		if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
+		skb = validate_xmit_skb(skb, dev);
+		if (skb && sch_direct_xmit(skb, q, dev, txq, root_lock)) {
 			if (unlikely(contended)) {
 				spin_unlock(&q->busylock);
 				contended = false;
@@ -2925,11 +2886,15 @@ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
 			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
 				goto recursion_alert;
 
+			skb = validate_xmit_skb(skb, dev);
+			if (!skb)
+				goto drop;
+
 			HARD_TX_LOCK(dev, txq, cpu);
 
 			if (!netif_xmit_stopped(txq)) {
 				__this_cpu_inc(xmit_recursion);
-				rc = dev_hard_start_xmit(skb, dev, txq);
+				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
 				__this_cpu_dec(xmit_recursion);
 				if (dev_xmit_complete(rc)) {
 					HARD_TX_UNLOCK(dev, txq);
@@ -2950,10 +2915,11 @@ recursion_alert:
 	}
 
 	rc = -ENETDOWN;
+drop:
 	rcu_read_unlock_bh();
 
 	atomic_long_inc(&dev->tx_dropped);
-	kfree_skb(skb);
+	kfree_skb_list(skb);
 	return rc;
 out:
 	rcu_read_unlock_bh();
@@ -3130,8 +3096,7 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 	}
 
 	if (map) {
-		tcpu = map->cpus[((u64) hash * map->len) >> 32];
-
+		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
 		if (cpu_online(tcpu)) {
 			cpu = tcpu;
 			goto done;
@@ -3965,11 +3930,10 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 	if (!(skb->dev->features & NETIF_F_GRO))
 		goto normal;
 
-	if (skb_is_gso(skb) || skb_has_frag_list(skb))
+	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
 		goto normal;
 
 	gro_list_prepare(napi, skb);
-	NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(ptype, head, list) {
@@ -3983,6 +3947,22 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 		NAPI_GRO_CB(skb)->free = 0;
 		NAPI_GRO_CB(skb)->udp_mark = 0;
 
+		/* Setup for GRO checksum validation */
+		switch (skb->ip_summed) {
+		case CHECKSUM_COMPLETE:
+			NAPI_GRO_CB(skb)->csum = skb->csum;
+			NAPI_GRO_CB(skb)->csum_valid = 1;
+			NAPI_GRO_CB(skb)->csum_cnt = 0;
+			break;
+		case CHECKSUM_UNNECESSARY:
+			NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
+			NAPI_GRO_CB(skb)->csum_valid = 0;
+			break;
+		default:
+			NAPI_GRO_CB(skb)->csum_cnt = 0;
+			NAPI_GRO_CB(skb)->csum_valid = 0;
+		}
+
 		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
 		break;
 	}
@@ -4212,6 +4192,31 @@ gro_result_t napi_gro_frags(struct napi_struct *napi)
 }
 EXPORT_SYMBOL(napi_gro_frags);
 
+/* Compute the checksum from gro_offset and return the folded value
+ * after adding in any pseudo checksum.
+ */
+__sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
+{
+	__wsum wsum;
+	__sum16 sum;
+
+	wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);
+
+	/* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
+	sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
+	if (likely(!sum)) {
+		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
+		    !skb->csum_complete_sw)
+			netdev_rx_csum_fault(skb->dev);
+	}
+
+	NAPI_GRO_CB(skb)->csum = wsum;
+	NAPI_GRO_CB(skb)->csum_valid = 1;
+
+	return sum;
+}
+EXPORT_SYMBOL(__skb_gro_checksum_complete);
+
 /*
  * net_rps_action_and_irq_enable sends any pending IPI's for rps.
  * Note: called with local irq disabled, but exits with local irq enabled.