1 files changed, 30 insertions, 11 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index a5cbf67517f0..be196e89ab6c 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -110,9 +110,11 @@ do {								\
  * overload it to mean fasync when stored there.
  */
 #define TUN_FASYNC	IFF_ATTACH_QUEUE
+/* High bits in flags field are unused. */
+#define TUN_VNET_LE     0x80000000
 
 #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \
-		      IFF_VNET_LE | IFF_MULTI_QUEUE)
+		      IFF_MULTI_QUEUE)
 #define GOODCOPY_LEN 128
 
 #define FLT_EXACT_COUNT 8
@@ -122,10 +124,9 @@ struct tap_filter {
 	unsigned char	addr[FLT_EXACT_COUNT][ETH_ALEN];
 };
 
-/* DEFAULT_MAX_NUM_RSS_QUEUES were chosen to let the rx/tx queues allocated for
- * the netdevice to be fit in one page. So we can make sure the success of
- * memory allocation. TODO: increase the limit. */
-#define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES
+/* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal
+ * to max number of VCPUs in guest. */
+#define MAX_TAP_QUEUES 256
 #define MAX_TAP_FLOWS  4096
 
 #define TUN_FLOW_EXPIRE (3 * HZ)
@@ -208,12 +209,12 @@ struct tun_struct {
 
 static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val)
 {
-	return __virtio16_to_cpu(tun->flags & IFF_VNET_LE, val);
+	return __virtio16_to_cpu(tun->flags & TUN_VNET_LE, val);
 }
 
 static inline __virtio16 cpu_to_tun16(struct tun_struct *tun, u16 val)
 {
-	return __cpu_to_virtio16(tun->flags & IFF_VNET_LE, val);
+	return __cpu_to_virtio16(tun->flags & TUN_VNET_LE, val);
 }
 
 static inline u32 tun_hashfn(u32 rxhash)
@@ -1259,7 +1260,7 @@ static ssize_t tun_put_user(struct tun_struct *tun,
 	int vlan_hlen = 0;
 	int vnet_hdr_sz = 0;
 
-	if (vlan_tx_tag_present(skb))
+	if (skb_vlan_tag_present(skb))
 		vlan_hlen = VLAN_HLEN;
 
 	if (tun->flags & IFF_VNET_HDR)
@@ -1336,7 +1337,7 @@ static ssize_t tun_put_user(struct tun_struct *tun,
 		} veth;
 
 		veth.h_vlan_proto = skb->vlan_proto;
-		veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
+		veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb));
 
 		vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
 
@@ -1378,7 +1379,7 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
 	skb = __skb_recv_datagram(tfile->socket.sk, noblock ? MSG_DONTWAIT : 0,
 				  &peeked, &off, &err);
 	if (!skb)
-		return 0;
+		return err;
 
 	ret = tun_put_user(tun, tfile, skb, to);
 	if (unlikely(ret < 0))
@@ -1499,7 +1500,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
 		goto out;
 	}
 	ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT);
-	if (ret > total_len) {
+	if (ret > (ssize_t)total_len) {
 		m->msg_flags |= MSG_TRUNC;
 		ret = flags & MSG_TRUNC ? ret : total_len;
 	}
@@ -1843,6 +1844,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 	int sndbuf;
 	int vnet_hdr_sz;
 	unsigned int ifindex;
+	int le;
 	int ret;
 
 	if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) {
@@ -2042,6 +2044,23 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		tun->vnet_hdr_sz = vnet_hdr_sz;
 		break;
 
+	case TUNGETVNETLE:
+		le = !!(tun->flags & TUN_VNET_LE);
+		if (put_user(le, (int __user *)argp))
+			ret = -EFAULT;
+		break;
+
+	case TUNSETVNETLE:
+		if (get_user(le, (int __user *)argp)) {
+			ret = -EFAULT;
+			break;
+		}
+		if (le)
+			tun->flags |= TUN_VNET_LE;
+		else
+			tun->flags &= ~TUN_VNET_LE;
+		break;
+
 	case TUNATTACHFILTER:
 		/* Can be set only for TAPs */
 		ret = -EINVAL;