VSOCK: use TCP state constants for sk_state

There are two state fields: socket->state and sock->sk_state.  The
socket->state field uses SS_UNCONNECTED, SS_CONNECTED, etc while the
sock->sk_state typically uses values that match TCP state constants
(TCP_CLOSE, TCP_ESTABLISHED).  AF_VSOCK does not follow this convention
and instead uses SS_* constants for both fields.

The sk_state field will be exposed to userspace through the vsock_diag
interface for ss(8), netstat(8), and other programs.

This patch switches sk_state to TCP state constants so that the meaning
of this field is consistent with other address families.  Not just
AF_INET and AF_INET6 use the TCP constants, AF_UNIX and others do too.

The following mapping was used to convert the code:

  SS_FREE -> TCP_CLOSE
  SS_UNCONNECTED -> TCP_CLOSE
  SS_CONNECTING -> TCP_SYN_SENT
  SS_CONNECTED -> TCP_ESTABLISHED
  SS_DISCONNECTING -> TCP_CLOSING
  VSOCK_SS_LISTEN -> TCP_LISTEN

In __vsock_create() the sk_state initialization was dropped because
sock_init_data() already initializes sk_state to TCP_CLOSE.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 27 insertions, 19 deletions

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 9b179a0081b3..98359c19522f 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -36,7 +36,7 @@
  * not support simultaneous connects (two "client" sockets connecting).
  *
  * - "Server" sockets are referred to as listener sockets throughout this
- * implementation because they are in the VSOCK_SS_LISTEN state.  When a
+ * implementation because they are in the TCP_LISTEN state.  When a
  * connection request is received (the second kind of socket mentioned above),
  * we create a new socket and refer to it as a pending socket.  These pending
  * sockets are placed on the pending connection list of the listener socket.
@@ -82,6 +82,15 @@
  * argument, we must ensure the reference count is increased to ensure the
  * socket isn't freed before the function is run; the deferred function will
  * then drop the reference.
+ *
+ * - sk->sk_state uses the TCP state constants because they are widely used by
+ * other address families and exposed to userspace tools like ss(8):
+ *
+ *   TCP_CLOSE - unconnected
+ *   TCP_SYN_SENT - connecting
+ *   TCP_ESTABLISHED - connected
+ *   TCP_CLOSING - disconnecting
+ *   TCP_LISTEN - listening
  */
 
 #include <linux/types.h>
@@ -477,7 +486,7 @@ void vsock_pending_work(struct work_struct *work)
 	if (vsock_in_connected_table(vsk))
 		vsock_remove_connected(vsk);
 
-	sk->sk_state = SS_FREE;
+	sk->sk_state = TCP_CLOSE;
 
 out:
 	release_sock(sk);
@@ -617,7 +626,6 @@ struct sock *__vsock_create(struct net *net,
 
 	sk->sk_destruct = vsock_sk_destruct;
 	sk->sk_backlog_rcv = vsock_queue_rcv_skb;
-	sk->sk_state = 0;
 	sock_reset_flag(sk, SOCK_DONE);
 
 	INIT_LIST_HEAD(&vsk->bound_table);
@@ -891,7 +899,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		/* Listening sockets that have connections in their accept
 		 * queue can be read.
 		 */
-		if (sk->sk_state == VSOCK_SS_LISTEN
+		if (sk->sk_state == TCP_LISTEN
 		    && !vsock_is_accept_queue_empty(sk))
 			mask |= POLLIN | POLLRDNORM;
 
@@ -920,7 +928,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		}
 
 		/* Connected sockets that can produce data can be written. */
-		if (sk->sk_state == SS_CONNECTED) {
+		if (sk->sk_state == TCP_ESTABLISHED) {
 			if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
 				bool space_avail_now = false;
 				int ret = transport->notify_poll_out(
@@ -942,7 +950,7 @@ static unsigned int vsock_poll(struct file *file, struct socket *sock,
 		 * POLLOUT|POLLWRNORM when peer is closed and nothing to read,
 		 * but local send is not shutdown.
 		 */
-		if (sk->sk_state == SS_UNCONNECTED) {
+		if (sk->sk_state == TCP_CLOSE) {
 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 				mask |= POLLOUT | POLLWRNORM;
 
@@ -1112,9 +1120,9 @@ static void vsock_connect_timeout(struct work_struct *work)
 	sk = sk_vsock(vsk);
 
 	lock_sock(sk);
-	if (sk->sk_state == SS_CONNECTING &&
+	if (sk->sk_state == TCP_SYN_SENT &&
 	    (sk->sk_shutdown != SHUTDOWN_MASK)) {
-		sk->sk_state = SS_UNCONNECTED;
+		sk->sk_state = TCP_CLOSE;
 		sk->sk_err = ETIMEDOUT;
 		sk->sk_error_report(sk);
 		cancel = 1;
@@ -1160,7 +1168,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 		err = -EALREADY;
 		break;
 	default:
-		if ((sk->sk_state == VSOCK_SS_LISTEN) ||
+		if ((sk->sk_state == TCP_LISTEN) ||
 		    vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
 			err = -EINVAL;
 			goto out;
@@ -1183,7 +1191,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 		if (err)
 			goto out;
 
-		sk->sk_state = SS_CONNECTING;
+		sk->sk_state = TCP_SYN_SENT;
 
 		err = transport->connect(vsk);
 		if (err < 0)
@@ -1203,7 +1211,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 	timeout = vsk->connect_timeout;
 	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 
-	while (sk->sk_state != SS_CONNECTED && sk->sk_err == 0) {
+	while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
 		if (flags & O_NONBLOCK) {
 			/* If we're not going to block, we schedule a timeout
 			 * function to generate a timeout on the connection
@@ -1226,13 +1234,13 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 
 		if (signal_pending(current)) {
 			err = sock_intr_errno(timeout);
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			sock->state = SS_UNCONNECTED;
 			vsock_transport_cancel_pkt(vsk);
 			goto out_wait;
 		} else if (timeout == 0) {
 			err = -ETIMEDOUT;
-			sk->sk_state = SS_UNCONNECTED;
+			sk->sk_state = TCP_CLOSE;
 			sock->state = SS_UNCONNECTED;
 			vsock_transport_cancel_pkt(vsk);
 			goto out_wait;
@@ -1243,7 +1251,7 @@ static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 
 	if (sk->sk_err) {
 		err = -sk->sk_err;
-		sk->sk_state = SS_UNCONNECTED;
+		sk->sk_state = TCP_CLOSE;
 		sock->state = SS_UNCONNECTED;
 	} else {
 		err = 0;
@@ -1276,7 +1284,7 @@ static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
 		goto out;
 	}
 
-	if (listener->sk_state != VSOCK_SS_LISTEN) {
+	if (listener->sk_state != TCP_LISTEN) {
 		err = -EINVAL;
 		goto out;
 	}
@@ -1366,7 +1374,7 @@ static int vsock_listen(struct socket *sock, int backlog)
 	}
 
 	sk->sk_max_ack_backlog = backlog;
-	sk->sk_state = VSOCK_SS_LISTEN;
+	sk->sk_state = TCP_LISTEN;
 
 	err = 0;
 
@@ -1546,7 +1554,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 
 	/* Callers should not provide a destination with stream sockets. */
 	if (msg->msg_namelen) {
-		err = sk->sk_state == SS_CONNECTED ? -EISCONN : -EOPNOTSUPP;
+		err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
 		goto out;
 	}
 
@@ -1557,7 +1565,7 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 		goto out;
 	}
 
-	if (sk->sk_state != SS_CONNECTED ||
+	if (sk->sk_state != TCP_ESTABLISHED ||
 	    !vsock_addr_bound(&vsk->local_addr)) {
 		err = -ENOTCONN;
 		goto out;
@@ -1681,7 +1689,7 @@ vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 
 	lock_sock(sk);
 
-	if (sk->sk_state != SS_CONNECTED) {
+	if (sk->sk_state != TCP_ESTABLISHED) {
 		/* Recvmsg is supposed to return 0 if a peer performs an
 		 * orderly shutdown. Differentiate between that case and when a
 		 * peer has not connected or a local shutdown occured with the