1 files changed, 66 insertions, 58 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index f5e9ac00a07..71f3d1a35b7 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -123,6 +123,9 @@ struct tun_struct {
 	gid_t			group;
 
 	struct net_device	*dev;
+	u32			set_features;
+#define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
+			  NETIF_F_TSO6|NETIF_F_UFO)
 	struct fasync_struct	*fasync;
 
 	struct tap_filter       txflt;
@@ -451,12 +454,39 @@ tun_net_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
+static u32 tun_net_fix_features(struct net_device *dev, u32 features)
+{
+	struct tun_struct *tun = netdev_priv(dev);
+
+	return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
+}
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void tun_poll_controller(struct net_device *dev)
+{
+	/*
+	 * Tun only receives frames when:
+	 * 1) the char device endpoint gets data from user space
+	 * 2) the tun socket gets a sendmsg call from user space
+	 * Since both of those are syncronous operations, we are guaranteed
+	 * never to have pending data when we poll for it
+	 * so theres nothing to do here but return.
+	 * We need this though so netpoll recognizes us as an interface that
+	 * supports polling, which enables bridge devices in virt setups to
+	 * still use netconsole
+	 */
+	return;
+}
+#endif
 static const struct net_device_ops tun_netdev_ops = {
 	.ndo_uninit		= tun_net_uninit,
 	.ndo_open		= tun_net_open,
 	.ndo_stop		= tun_net_close,
 	.ndo_start_xmit		= tun_net_xmit,
 	.ndo_change_mtu		= tun_net_change_mtu,
+	.ndo_fix_features	= tun_net_fix_features,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= tun_poll_controller,
+#endif
 };
 
 static const struct net_device_ops tap_netdev_ops = {
@@ -465,9 +495,13 @@ static const struct net_device_ops tap_netdev_ops = {
 	.ndo_stop		= tun_net_close,
 	.ndo_start_xmit		= tun_net_xmit,
 	.ndo_change_mtu		= tun_net_change_mtu,
+	.ndo_fix_features	= tun_net_fix_features,
 	.ndo_set_multicast_list	= tun_net_mclist,
 	.ndo_set_mac_address	= eth_mac_addr,
 	.ndo_validate_addr	= eth_validate_addr,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= tun_poll_controller,
+#endif
 };
 
 /* Initialize net device. */
@@ -494,6 +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);
 
@@ -538,9 +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;
@@ -566,13 +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;
 
@@ -602,7 +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;
@@ -628,8 +663,7 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
 			kfree_skb(skb);
 			return -EINVAL;
 		}
-	} else if (tun->flags & TUN_NOCHECKSUM)
-		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	}
 
 	switch (tun->flags & TUN_TYPE_MASK) {
 	case TUN_TUN_DEV:
@@ -655,7 +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");
@@ -718,9 +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;
@@ -777,6 +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,
@@ -806,7 +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;
 
@@ -837,7 +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;
 }
@@ -1088,11 +1126,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 
 		tun_net_init(dev);
 
-		if (strchr(dev->name, '%')) {
-			err = dev_alloc_name(dev, dev->name);
-			if (err < 0)
-				goto err_free_sk;
-		}
+		dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST |
+			TUN_USER_FEATURES;
+		dev->features = dev->hw_features;
 
 		err = register_netdevice(tun->dev);
 		if (err < 0)
@@ -1158,18 +1194,12 @@ static int tun_get_iff(struct net *net, struct tun_struct *tun,
 
 /* This is like a cut-down ethtool ops, except done via tun fd so no
  * privs required. */
-static int set_offload(struct net_device *dev, unsigned long arg)
+static int set_offload(struct tun_struct *tun, unsigned long arg)
 {
-	u32 old_features, features;
-
-	old_features = dev->features;
-	/* Unset features, set them as we chew on the arg. */
-	features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
-				    |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6
-				    |NETIF_F_UFO));
+	u32 features = 0;
 
 	if (arg & TUN_F_CSUM) {
-		features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
+		features |= NETIF_F_HW_CSUM;
 		arg &= ~TUN_F_CSUM;
 
 		if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
@@ -1195,9 +1225,8 @@ static int set_offload(struct net_device *dev, unsigned long arg)
 	if (arg)
 		return -EINVAL;
 
-	dev->features = features;
-	if (old_features != dev->features)
-		netdev_features_change(dev);
+	tun->set_features = features;
+	netdev_update_features(tun->dev);
 
 	return 0;
 }
@@ -1262,12 +1291,9 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 
 	case TUNSETNOCSUM:
 		/* Disable/Enable checksum */
-		if (arg)
-			tun->flags |= TUN_NOCHECKSUM;
-		else
-			tun->flags &= ~TUN_NOCHECKSUM;
 
-		tun_debug(KERN_INFO, tun, "checksum %s\n",
+		/* [unimplemented] */
+		tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n",
 			  arg ? "disabled" : "enabled");
 		break;
 
@@ -1316,7 +1342,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		break;
 #endif
 	case TUNSETOFFLOAD:
-		ret = set_offload(tun->dev, arg);
+		ret = set_offload(tun, arg);
 		break;
 
 	case TUNSETTXFILTER:
@@ -1548,7 +1574,7 @@ static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 {
 	cmd->supported		= 0;
 	cmd->advertising	= 0;
-	cmd->speed		= SPEED_10;
+	ethtool_cmd_speed_set(cmd, SPEED_10);
 	cmd->duplex		= DUPLEX_FULL;
 	cmd->port		= PORT_TP;
 	cmd->phy_address	= 0;
@@ -1595,30 +1621,12 @@ static void tun_set_msglevel(struct net_device *dev, u32 value)
 #endif
 }
 
-static u32 tun_get_rx_csum(struct net_device *dev)
-{
-	struct tun_struct *tun = netdev_priv(dev);
-	return (tun->flags & TUN_NOCHECKSUM) == 0;
-}
-
-static int tun_set_rx_csum(struct net_device *dev, u32 data)
-{
-	struct tun_struct *tun = netdev_priv(dev);
-	if (data)
-		tun->flags &= ~TUN_NOCHECKSUM;
-	else
-		tun->flags |= TUN_NOCHECKSUM;
-	return 0;
-}
-
 static const struct ethtool_ops tun_ethtool_ops = {
 	.get_settings	= tun_get_settings,
 	.get_drvinfo	= tun_get_drvinfo,
 	.get_msglevel	= tun_get_msglevel,
 	.set_msglevel	= tun_set_msglevel,
 	.get_link	= ethtool_op_get_link,
-	.get_rx_csum	= tun_get_rx_csum,
-	.set_rx_csum	= tun_set_rx_csum
 };