1 files changed, 19 insertions, 14 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 5235f48be1b..71f3d1a35b7 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -528,6 +528,7 @@ static void tun_net_init(struct net_device *dev)
 		dev->netdev_ops = &tap_netdev_ops;
 		/* Ethernet TAP Device */
 		ether_setup(dev);
+		dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 
 		random_ether_addr(dev->dev_addr);
 
@@ -572,9 +573,9 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
 
 /* prepad is the amount to reserve at front.  len is length after that.
  * linear is a hint as to how much to copy (usually headers). */
-static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
-					    size_t prepad, size_t len,
-					    size_t linear, int noblock)
+static struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
+				     size_t prepad, size_t len,
+				     size_t linear, int noblock)
 {
 	struct sock *sk = tun->socket.sk;
 	struct sk_buff *skb;
@@ -600,13 +601,13 @@ static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
 }
 
 /* Get packet from user space buffer */
-static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
-				       const struct iovec *iv, size_t count,
-				       int noblock)
+static ssize_t tun_get_user(struct tun_struct *tun,
+			    const struct iovec *iv, size_t count,
+			    int noblock)
 {
 	struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
 	struct sk_buff *skb;
-	size_t len = count, align = 0;
+	size_t len = count, align = NET_SKB_PAD;
 	struct virtio_net_hdr gso = { 0 };
 	int offset = 0;
 
@@ -636,7 +637,7 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
 	}
 
 	if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
-		align = NET_IP_ALIGN;
+		align += NET_IP_ALIGN;
 		if (unlikely(len < ETH_HLEN ||
 			     (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
 			return -EINVAL;
@@ -688,7 +689,7 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
 	case TUN_TAP_DEV:
 		skb->protocol = eth_type_trans(skb, tun->dev);
 		break;
-	};
+	}
 
 	if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 		pr_debug("GSO!\n");
@@ -751,9 +752,9 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
 }
 
 /* Put packet to the user space buffer */
-static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
-				       struct sk_buff *skb,
-				       const struct iovec *iv, int len)
+static ssize_t tun_put_user(struct tun_struct *tun,
+			    struct sk_buff *skb,
+			    const struct iovec *iv, int len)
 {
 	struct tun_pi pi = { 0, skb->protocol };
 	ssize_t total = 0;
@@ -810,6 +811,8 @@ static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
 			gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 			gso.csum_start = skb_checksum_start_offset(skb);
 			gso.csum_offset = skb->csum_offset;
+		} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
+			gso.flags = VIRTIO_NET_HDR_F_DATA_VALID;
 		} /* else everything is zero */
 
 		if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
@@ -839,7 +842,8 @@ static ssize_t tun_do_read(struct tun_struct *tun,
 
 	tun_debug(KERN_INFO, tun, "tun_chr_read\n");
 
-	add_wait_queue(&tun->wq.wait, &wait);
+	if (unlikely(!noblock))
+		add_wait_queue(&tun->wq.wait, &wait);
 	while (len) {
 		current->state = TASK_INTERRUPTIBLE;
 
@@ -870,7 +874,8 @@ static ssize_t tun_do_read(struct tun_struct *tun,
 	}
 
 	current->state = TASK_RUNNING;
-	remove_wait_queue(&tun->wq.wait, &wait);
+	if (unlikely(!noblock))
+		remove_wait_queue(&tun->wq.wait, &wait);
 
 	return ret;
 }