1 files changed, 246 insertions, 165 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index fd5f042dbff4..9b4e4833a484 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1,8 +1,8 @@
 /*
  * net/tipc/socket.c: TIPC socket API
  *
- * Copyright (c) 2001-2007, Ericsson AB
- * Copyright (c) 2004-2008, 2010-2011, Wind River Systems
+ * Copyright (c) 2001-2007, 2012 Ericsson AB
+ * Copyright (c) 2004-2008, 2010-2012, Wind River Systems
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -43,7 +43,7 @@
 #define SS_LISTENING	-1	/* socket is listening */
 #define SS_READY	-2	/* socket is connectionless */
 
-#define OVERLOAD_LIMIT_BASE	5000
+#define OVERLOAD_LIMIT_BASE	10000
 #define CONN_TIMEOUT_DEFAULT	8000	/* default connect timeout = 8s */
 
 struct tipc_sock {
@@ -62,6 +62,8 @@ struct tipc_sock {
 static int backlog_rcv(struct sock *sk, struct sk_buff *skb);
 static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf);
 static void wakeupdispatch(struct tipc_port *tport);
+static void tipc_data_ready(struct sock *sk, int len);
+static void tipc_write_space(struct sock *sk);
 
 static const struct proto_ops packet_ops;
 static const struct proto_ops stream_ops;
@@ -71,8 +73,6 @@ static struct proto tipc_proto;
 
 static int sockets_enabled;
 
-static atomic_t tipc_queue_size = ATOMIC_INIT(0);
-
 /*
  * Revised TIPC socket locking policy:
  *
@@ -126,7 +126,6 @@ static atomic_t tipc_queue_size = ATOMIC_INIT(0);
 static void advance_rx_queue(struct sock *sk)
 {
 	kfree_skb(__skb_dequeue(&sk->sk_receive_queue));
-	atomic_dec(&tipc_queue_size);
 }
 
 /**
@@ -138,10 +137,8 @@ static void discard_rx_queue(struct sock *sk)
 {
 	struct sk_buff *buf;
 
-	while ((buf = __skb_dequeue(&sk->sk_receive_queue))) {
-		atomic_dec(&tipc_queue_size);
+	while ((buf = __skb_dequeue(&sk->sk_receive_queue)))
 		kfree_skb(buf);
-	}
 }
 
 /**
@@ -153,10 +150,8 @@ static void reject_rx_queue(struct sock *sk)
 {
 	struct sk_buff *buf;
 
-	while ((buf = __skb_dequeue(&sk->sk_receive_queue))) {
+	while ((buf = __skb_dequeue(&sk->sk_receive_queue)))
 		tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
-		atomic_dec(&tipc_queue_size);
-	}
 }
 
 /**
@@ -221,6 +216,8 @@ static int tipc_create(struct net *net, struct socket *sock, int protocol,
 	sock_init_data(sock, sk);
 	sk->sk_backlog_rcv = backlog_rcv;
 	sk->sk_rcvbuf = TIPC_FLOW_CONTROL_WIN * 2 * TIPC_MAX_USER_MSG_SIZE * 2;
+	sk->sk_data_ready = tipc_data_ready;
+	sk->sk_write_space = tipc_write_space;
 	tipc_sk(sk)->p = tp_ptr;
 	tipc_sk(sk)->conn_timeout = CONN_TIMEOUT_DEFAULT;
 
@@ -276,7 +273,6 @@ static int release(struct socket *sock)
 		buf = __skb_dequeue(&sk->sk_receive_queue);
 		if (buf == NULL)
 			break;
-		atomic_dec(&tipc_queue_size);
 		if (TIPC_SKB_CB(buf)->handle != 0)
 			kfree_skb(buf);
 		else {
@@ -408,7 +404,7 @@ static int get_name(struct socket *sock, struct sockaddr *uaddr,
  * socket state		flags set
  * ------------		---------
  * unconnected		no read flags
- *			no write flags
+ *			POLLOUT if port is not congested
  *
  * connecting		POLLIN/POLLRDNORM if ACK/NACK in rx queue
  *			no write flags
@@ -435,9 +431,13 @@ static unsigned int poll(struct file *file, struct socket *sock,
 	struct sock *sk = sock->sk;
 	u32 mask = 0;
 
-	poll_wait(file, sk_sleep(sk), wait);
+	sock_poll_wait(file, sk_sleep(sk), wait);
 
 	switch ((int)sock->state) {
+	case SS_UNCONNECTED:
+		if (!tipc_sk_port(sk)->congested)
+			mask |= POLLOUT;
+		break;
 	case SS_READY:
 	case SS_CONNECTED:
 		if (!tipc_sk_port(sk)->congested)
@@ -775,16 +775,19 @@ exit:
 static int auto_connect(struct socket *sock, struct tipc_msg *msg)
 {
 	struct tipc_sock *tsock = tipc_sk(sock->sk);
-
-	if (msg_errcode(msg)) {
-		sock->state = SS_DISCONNECTING;
-		return -ECONNREFUSED;
-	}
+	struct tipc_port *p_ptr;
 
 	tsock->peer_name.ref = msg_origport(msg);
 	tsock->peer_name.node = msg_orignode(msg);
-	tipc_connect2port(tsock->p->ref, &tsock->peer_name);
-	tipc_set_portimportance(tsock->p->ref, msg_importance(msg));
+	p_ptr = tipc_port_deref(tsock->p->ref);
+	if (!p_ptr)
+		return -EINVAL;
+
+	__tipc_connect(tsock->p->ref, p_ptr, &tsock->peer_name);
+
+	if (msg_importance(msg) > TIPC_CRITICAL_IMPORTANCE)
+		return -EINVAL;
+	msg_set_importance(&p_ptr->phdr, (u32)msg_importance(msg));
 	sock->state = SS_CONNECTED;
 	return 0;
 }
@@ -943,13 +946,6 @@ restart:
 	sz = msg_data_sz(msg);
 	err = msg_errcode(msg);
 
-	/* Complete connection setup for an implied connect */
-	if (unlikely(sock->state == SS_CONNECTING)) {
-		res = auto_connect(sock, msg);
-		if (res)
-			goto exit;
-	}
-
 	/* Discard an empty non-errored message & try again */
 	if ((!sz) && (!err)) {
 		advance_rx_queue(sk);
@@ -1126,6 +1122,39 @@ exit:
 }
 
 /**
+ * tipc_write_space - wake up thread if port congestion is released
+ * @sk: socket
+ */
+static void tipc_write_space(struct sock *sk)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
+						POLLWRNORM | POLLWRBAND);
+	rcu_read_unlock();
+}
+
+/**
+ * tipc_data_ready - wake up threads to indicate messages have been received
+ * @sk: socket
+ * @len: the length of messages
+ */
+static void tipc_data_ready(struct sock *sk, int len)
+{
+	struct socket_wq *wq;
+
+	rcu_read_lock();
+	wq = rcu_dereference(sk->sk_wq);
+	if (wq_has_sleeper(wq))
+		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
+						POLLRDNORM | POLLRDBAND);
+	rcu_read_unlock();
+}
+
+/**
  * rx_queue_full - determine if receive queue can accept another message
  * @msg: message to be added to queue
  * @queue_size: current size of queue
@@ -1154,6 +1183,83 @@ static int rx_queue_full(struct tipc_msg *msg, u32 queue_size, u32 base)
 }
 
 /**
+ * filter_connect - Handle all incoming messages for a connection-based socket
+ * @tsock: TIPC socket
+ * @msg: message
+ *
+ * Returns TIPC error status code and socket error status code
+ * once it encounters some errors
+ */
+static u32 filter_connect(struct tipc_sock *tsock, struct sk_buff **buf)
+{
+	struct socket *sock = tsock->sk.sk_socket;
+	struct tipc_msg *msg = buf_msg(*buf);
+	struct sock *sk = &tsock->sk;
+	u32 retval = TIPC_ERR_NO_PORT;
+	int res;
+
+	if (msg_mcast(msg))
+		return retval;
+
+	switch ((int)sock->state) {
+	case SS_CONNECTED:
+		/* Accept only connection-based messages sent by peer */
+		if (msg_connected(msg) && tipc_port_peer_msg(tsock->p, msg)) {
+			if (unlikely(msg_errcode(msg))) {
+				sock->state = SS_DISCONNECTING;
+				__tipc_disconnect(tsock->p);
+			}
+			retval = TIPC_OK;
+		}
+		break;
+	case SS_CONNECTING:
+		/* Accept only ACK or NACK message */
+		if (unlikely(msg_errcode(msg))) {
+			sock->state = SS_DISCONNECTING;
+			sk->sk_err = -ECONNREFUSED;
+			retval = TIPC_OK;
+			break;
+		}
+
+		if (unlikely(!msg_connected(msg)))
+			break;
+
+		res = auto_connect(sock, msg);
+		if (res) {
+			sock->state = SS_DISCONNECTING;
+			sk->sk_err = res;
+			retval = TIPC_OK;
+			break;
+		}
+
+		/* If an incoming message is an 'ACK-', it should be
+		 * discarded here because it doesn't contain useful
+		 * data. In addition, we should try to wake up
+		 * connect() routine if sleeping.
+		 */
+		if (msg_data_sz(msg) == 0) {
+			kfree_skb(*buf);
+			*buf = NULL;
+			if (waitqueue_active(sk_sleep(sk)))
+				wake_up_interruptible(sk_sleep(sk));
+		}
+		retval = TIPC_OK;
+		break;
+	case SS_LISTENING:
+	case SS_UNCONNECTED:
+		/* Accept only SYN message */
+		if (!msg_connected(msg) && !(msg_errcode(msg)))
+			retval = TIPC_OK;
+		break;
+	case SS_DISCONNECTING:
+		break;
+	default:
+		pr_err("Unknown socket state %u\n", sock->state);
+	}
+	return retval;
+}
+
+/**
  * filter_rcv - validate incoming message
  * @sk: socket
  * @buf: message
@@ -1170,6 +1276,7 @@ static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
 	struct socket *sock = sk->sk_socket;
 	struct tipc_msg *msg = buf_msg(buf);
 	u32 recv_q_len;
+	u32 res = TIPC_OK;
 
 	/* Reject message if it is wrong sort of message for socket */
 	if (msg_type(msg) > TIPC_DIRECT_MSG)
@@ -1179,32 +1286,12 @@ static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
 		if (msg_connected(msg))
 			return TIPC_ERR_NO_PORT;
 	} else {
-		if (msg_mcast(msg))
-			return TIPC_ERR_NO_PORT;
-		if (sock->state == SS_CONNECTED) {
-			if (!msg_connected(msg) ||
-			    !tipc_port_peer_msg(tipc_sk_port(sk), msg))
-				return TIPC_ERR_NO_PORT;
-		} else if (sock->state == SS_CONNECTING) {
-			if (!msg_connected(msg) && (msg_errcode(msg) == 0))
-				return TIPC_ERR_NO_PORT;
-		} else if (sock->state == SS_LISTENING) {
-			if (msg_connected(msg) || msg_errcode(msg))
-				return TIPC_ERR_NO_PORT;
-		} else if (sock->state == SS_DISCONNECTING) {
-			return TIPC_ERR_NO_PORT;
-		} else /* (sock->state == SS_UNCONNECTED) */ {
-			if (msg_connected(msg) || msg_errcode(msg))
-				return TIPC_ERR_NO_PORT;
-		}
+		res = filter_connect(tipc_sk(sk), &buf);
+		if (res != TIPC_OK || buf == NULL)
+			return res;
 	}
 
 	/* Reject message if there isn't room to queue it */
-	recv_q_len = (u32)atomic_read(&tipc_queue_size);
-	if (unlikely(recv_q_len >= OVERLOAD_LIMIT_BASE)) {
-		if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE))
-			return TIPC_ERR_OVERLOAD;
-	}
 	recv_q_len = skb_queue_len(&sk->sk_receive_queue);
 	if (unlikely(recv_q_len >= (OVERLOAD_LIMIT_BASE / 2))) {
 		if (rx_queue_full(msg, recv_q_len, OVERLOAD_LIMIT_BASE / 2))
@@ -1213,17 +1300,9 @@ static u32 filter_rcv(struct sock *sk, struct sk_buff *buf)
 
 	/* Enqueue message (finally!) */
 	TIPC_SKB_CB(buf)->handle = 0;
-	atomic_inc(&tipc_queue_size);
 	__skb_queue_tail(&sk->sk_receive_queue, buf);
 
-	/* Initiate connection termination for an incoming 'FIN' */
-	if (unlikely(msg_errcode(msg) && (sock->state == SS_CONNECTED))) {
-		sock->state = SS_DISCONNECTING;
-		tipc_disconnect_port(tipc_sk_port(sk));
-	}
-
-	if (waitqueue_active(sk_sleep(sk)))
-		wake_up_interruptible(sk_sleep(sk));
+	sk->sk_data_ready(sk, 0);
 	return TIPC_OK;
 }
 
@@ -1290,8 +1369,7 @@ static void wakeupdispatch(struct tipc_port *tport)
 {
 	struct sock *sk = (struct sock *)tport->usr_handle;
 
-	if (waitqueue_active(sk_sleep(sk)))
-		wake_up_interruptible(sk_sleep(sk));
+	sk->sk_write_space(sk);
 }
 
 /**
@@ -1309,8 +1387,6 @@ static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
 	struct sock *sk = sock->sk;
 	struct sockaddr_tipc *dst = (struct sockaddr_tipc *)dest;
 	struct msghdr m = {NULL,};
-	struct sk_buff *buf;
-	struct tipc_msg *msg;
 	unsigned int timeout;
 	int res;
 
@@ -1322,26 +1398,6 @@ static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
 		goto exit;
 	}
 
-	/* For now, TIPC does not support the non-blocking form of connect() */
-	if (flags & O_NONBLOCK) {
-		res = -EOPNOTSUPP;
-		goto exit;
-	}
-
-	/* Issue Posix-compliant error code if socket is in the wrong state */
-	if (sock->state == SS_LISTENING) {
-		res = -EOPNOTSUPP;
-		goto exit;
-	}
-	if (sock->state == SS_CONNECTING) {
-		res = -EALREADY;
-		goto exit;
-	}
-	if (sock->state != SS_UNCONNECTED) {
-		res = -EISCONN;
-		goto exit;
-	}
-
 	/*
 	 * Reject connection attempt using multicast address
 	 *
@@ -1353,49 +1409,66 @@ static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
 		goto exit;
 	}
 
-	/* Reject any messages already in receive queue (very unlikely) */
-	reject_rx_queue(sk);
+	timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout;
 
-	/* Send a 'SYN-' to destination */
-	m.msg_name = dest;
-	m.msg_namelen = destlen;
-	res = send_msg(NULL, sock, &m, 0);
-	if (res < 0)
+	switch (sock->state) {
+	case SS_UNCONNECTED:
+		/* Send a 'SYN-' to destination */
+		m.msg_name = dest;
+		m.msg_namelen = destlen;
+
+		/* If connect is in non-blocking case, set MSG_DONTWAIT to
+		 * indicate send_msg() is never blocked.
+		 */
+		if (!timeout)
+			m.msg_flags = MSG_DONTWAIT;
+
+		res = send_msg(NULL, sock, &m, 0);
+		if ((res < 0) && (res != -EWOULDBLOCK))
+			goto exit;
+
+		/* Just entered SS_CONNECTING state; the only
+		 * difference is that return value in non-blocking
+		 * case is EINPROGRESS, rather than EALREADY.
+		 */
+		res = -EINPROGRESS;
+		break;
+	case SS_CONNECTING:
+		res = -EALREADY;
+		break;
+	case SS_CONNECTED:
+		res = -EISCONN;
+		break;
+	default:
+		res = -EINVAL;
 		goto exit;
+	}
 
-	/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
-	timeout = tipc_sk(sk)->conn_timeout;
-	release_sock(sk);
-	res = wait_event_interruptible_timeout(*sk_sleep(sk),
-			(!skb_queue_empty(&sk->sk_receive_queue) ||
-			(sock->state != SS_CONNECTING)),
-			timeout ? (long)msecs_to_jiffies(timeout)
-				: MAX_SCHEDULE_TIMEOUT);
-	lock_sock(sk);
+	if (sock->state == SS_CONNECTING) {
+		if (!timeout)
+			goto exit;
 
-	if (res > 0) {
-		buf = skb_peek(&sk->sk_receive_queue);
-		if (buf != NULL) {
-			msg = buf_msg(buf);
-			res = auto_connect(sock, msg);
-			if (!res) {
-				if (!msg_data_sz(msg))
-					advance_rx_queue(sk);
-			}
-		} else {
-			if (sock->state == SS_CONNECTED)
-				res = -EISCONN;
+		/* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
+		release_sock(sk);
+		res = wait_event_interruptible_timeout(*sk_sleep(sk),
+				sock->state != SS_CONNECTING,
+				timeout ? (long)msecs_to_jiffies(timeout)
+					: MAX_SCHEDULE_TIMEOUT);
+		lock_sock(sk);
+		if (res <= 0) {
+			if (res == 0)
+				res = -ETIMEDOUT;
 			else
-				res = -ECONNREFUSED;
+				; /* leave "res" unchanged */
+			goto exit;
 		}
-	} else {
-		if (res == 0)
-			res = -ETIMEDOUT;
-		else
-			; /* leave "res" unchanged */
-		sock->state = SS_DISCONNECTING;
 	}
 
+	if (unlikely(sock->state == SS_DISCONNECTING))
+		res = sock_error(sk);
+	else
+		res = 0;
+
 exit:
 	release_sock(sk);
 	return res;
@@ -1436,8 +1509,13 @@ static int listen(struct socket *sock, int len)
  */
 static int accept(struct socket *sock, struct socket *new_sock, int flags)
 {
-	struct sock *sk = sock->sk;
+	struct sock *new_sk, *sk = sock->sk;
 	struct sk_buff *buf;
+	struct tipc_sock *new_tsock;
+	struct tipc_port *new_tport;
+	struct tipc_msg *msg;
+	u32 new_ref;
+
 	int res;
 
 	lock_sock(sk);
@@ -1463,48 +1541,51 @@ static int accept(struct socket *sock, struct socket *new_sock, int flags)
 	buf = skb_peek(&sk->sk_receive_queue);
 
 	res = tipc_create(sock_net(sock->sk), new_sock, 0, 0);
-	if (!res) {
-		struct sock *new_sk = new_sock->sk;
-		struct tipc_sock *new_tsock = tipc_sk(new_sk);
-		struct tipc_port *new_tport = new_tsock->p;
-		u32 new_ref = new_tport->ref;
-		struct tipc_msg *msg = buf_msg(buf);
-
-		lock_sock(new_sk);
-
-		/*
-		 * Reject any stray messages received by new socket
-		 * before the socket lock was taken (very, very unlikely)
-		 */
-		reject_rx_queue(new_sk);
-
-		/* Connect new socket to it's peer */
-		new_tsock->peer_name.ref = msg_origport(msg);
-		new_tsock->peer_name.node = msg_orignode(msg);
-		tipc_connect2port(new_ref, &new_tsock->peer_name);
-		new_sock->state = SS_CONNECTED;
-
-		tipc_set_portimportance(new_ref, msg_importance(msg));
-		if (msg_named(msg)) {
-			new_tport->conn_type = msg_nametype(msg);
-			new_tport->conn_instance = msg_nameinst(msg);
-		}
+	if (res)
+		goto exit;
 
-		/*
-		 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
-		 * Respond to 'SYN+' by queuing it on new socket.
-		 */
-		if (!msg_data_sz(msg)) {
-			struct msghdr m = {NULL,};
+	new_sk = new_sock->sk;
+	new_tsock = tipc_sk(new_sk);
+	new_tport = new_tsock->p;
+	new_ref = new_tport->ref;
+	msg = buf_msg(buf);
 
-			advance_rx_queue(sk);
-			send_packet(NULL, new_sock, &m, 0);
-		} else {
-			__skb_dequeue(&sk->sk_receive_queue);
-			__skb_queue_head(&new_sk->sk_receive_queue, buf);
-		}
-		release_sock(new_sk);
+	/* we lock on new_sk; but lockdep sees the lock on sk */
+	lock_sock_nested(new_sk, SINGLE_DEPTH_NESTING);
+
+	/*
+	 * Reject any stray messages received by new socket
+	 * before the socket lock was taken (very, very unlikely)
+	 */
+	reject_rx_queue(new_sk);
+
+	/* Connect new socket to it's peer */
+	new_tsock->peer_name.ref = msg_origport(msg);
+	new_tsock->peer_name.node = msg_orignode(msg);
+	tipc_connect(new_ref, &new_tsock->peer_name);
+	new_sock->state = SS_CONNECTED;
+
+	tipc_set_portimportance(new_ref, msg_importance(msg));
+	if (msg_named(msg)) {
+		new_tport->conn_type = msg_nametype(msg);
+		new_tport->conn_instance = msg_nameinst(msg);
 	}
+
+	/*
+	 * Respond to 'SYN-' by discarding it & returning 'ACK'-.
+	 * Respond to 'SYN+' by queuing it on new socket.
+	 */
+	if (!msg_data_sz(msg)) {
+		struct msghdr m = {NULL,};
+
+		advance_rx_queue(sk);
+		send_packet(NULL, new_sock, &m, 0);
+	} else {
+		__skb_dequeue(&sk->sk_receive_queue);
+		__skb_queue_head(&new_sk->sk_receive_queue, buf);
+	}
+	release_sock(new_sk);
+
 exit:
 	release_sock(sk);
 	return res;
@@ -1539,7 +1620,6 @@ restart:
 		/* Disconnect and send a 'FIN+' or 'FIN-' message to peer */
 		buf = __skb_dequeue(&sk->sk_receive_queue);
 		if (buf) {
-			atomic_dec(&tipc_queue_size);
 			if (TIPC_SKB_CB(buf)->handle != 0) {
 				kfree_skb(buf);
 				goto restart;
@@ -1556,10 +1636,11 @@ restart:
 
 	case SS_DISCONNECTING:
 
-		/* Discard any unreceived messages; wake up sleeping tasks */
+		/* Discard any unreceived messages */
 		discard_rx_queue(sk);
-		if (waitqueue_active(sk_sleep(sk)))
-			wake_up_interruptible(sk_sleep(sk));
+
+		/* Wake up anyone sleeping in poll */
+		sk->sk_state_change(sk);
 		res = 0;
 		break;
 
@@ -1677,7 +1758,7 @@ static int getsockopt(struct socket *sock,
 		/* no need to set "res", since already 0 at this point */
 		break;
 	case TIPC_NODE_RECVQ_DEPTH:
-		value = (u32)atomic_read(&tipc_queue_size);
+		value = 0; /* was tipc_queue_size, now obsolete */
 		break;
 	case TIPC_SOCK_RECVQ_DEPTH:
 		value = skb_queue_len(&sk->sk_receive_queue);