tun: remove unused parameter in tun_do_read()

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/tun.c

@@ -1289,8 +1289,7 @@ static ssize_t tun_put_user(struct tun_struct *tun,
 }
 
 static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
-			   struct kiocb *iocb, const struct iovec *iv,
-			   ssize_t len, int noblock)
+			   const struct iovec *iv, ssize_t len, int noblock)
 {
 	DECLARE_WAITQUEUE(wait, current);
 	struct sk_buff *skb;
@@ -1353,7 +1352,7 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
 		goto out;
 	}
 
-	ret = tun_do_read(tun, tfile, iocb, iv, len,
+	ret = tun_do_read(tun, tfile, iv, len,
 			  file->f_flags & O_NONBLOCK);
 	ret = min_t(ssize_t, ret, len);
 out:
@@ -1452,7 +1451,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
 					 SOL_PACKET, TUN_TX_TIMESTAMP);
 		goto out;
 	}
-	ret = tun_do_read(tun, tfile, iocb, m->msg_iov, total_len,
+	ret = tun_do_read(tun, tfile, m->msg_iov, total_len,
 			  flags & MSG_DONTWAIT);
 	if (ret > total_len) {
 		m->msg_flags |= MSG_TRUNC;