1 files changed, 7 insertions, 20 deletions

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 66c4b0c8d108..5993c7e2d723 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -238,9 +238,6 @@ void netvsc_xmit_completion(void *context)
 	struct sk_buff *skb = (struct sk_buff *)
 		(unsigned long)packet->send_completion_tid;
 
-	if (!packet->part_of_skb)
-		kfree(packet);
-
 	if (skb)
 		dev_kfree_skb_any(skb);
 }
@@ -392,7 +389,6 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 	u32 net_trans_info;
 	u32 hash;
 	u32 skb_length;
-	u32 head_room;
 	u32 pkt_sz;
 	struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
 
@@ -405,7 +401,6 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 
 check_size:
 	skb_length = skb->len;
-	head_room = skb_headroom(skb);
 	num_data_pgs = netvsc_get_slots(skb) + 2;
 	if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
 		net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
@@ -424,20 +419,14 @@ check_size:
 
 	pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE;
 
-	if (head_room < pkt_sz) {
-		packet = kmalloc(pkt_sz, GFP_ATOMIC);
-		if (!packet) {
-			/* out of memory, drop packet */
-			netdev_err(net, "unable to alloc hv_netvsc_packet\n");
-			ret = -ENOMEM;
-			goto drop;
-		}
-		packet->part_of_skb = false;
-	} else {
-		/* Use the headroom for building up the packet */
-		packet = (struct hv_netvsc_packet *)skb->head;
-		packet->part_of_skb = true;
+	ret = skb_cow_head(skb, pkt_sz);
+	if (ret) {
+		netdev_err(net, "unable to alloc hv_netvsc_packet\n");
+		ret = -ENOMEM;
+		goto drop;
 	}
+	/* Use the headroom for building up the packet */
+	packet = (struct hv_netvsc_packet *)skb->head;
 
 	packet->status = 0;
 	packet->xmit_more = skb->xmit_more;
@@ -594,8 +583,6 @@ drop:
 		net->stats.tx_bytes += skb_length;
 		net->stats.tx_packets++;
 	} else {
-		if (packet && !packet->part_of_skb)
-			kfree(packet);
 		if (ret != -EAGAIN) {
 			dev_kfree_skb_any(skb);
 			net->stats.tx_dropped++;