[SCSI] iscsi_tcp: wake xmit thread when killing session

If the connection is bad, then the xmit thread could
end up waiting a long time (up to sendtmeo seconds) in
tcp_sendpage. This patch has us set the sk_error and
wake up the xmit thread so we can quickly fail.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/iscsi_tcp.c

@@ -584,9 +584,10 @@ static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 	struct iscsi_conn *conn = cls_conn->dd_data;
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+	struct socket *sock = tcp_sw_conn->sock;
 
 	/* userspace may have goofed up and not bound us */
-	if (!tcp_sw_conn->sock)
+	if (!sock)
 		return;
 	/*
 	 * Make sure our recv side is stopped.
@@ -597,6 +598,11 @@ static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 	write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
 
+	if (sock->sk->sk_sleep && waitqueue_active(sock->sk->sk_sleep)) {
+		sock->sk->sk_err = EIO;
+		wake_up_interruptible(sock->sk->sk_sleep);
+	}
+
 	iscsi_conn_stop(cls_conn, flag);
 	iscsi_sw_tcp_release_conn(conn);
 }