Merge tag 'v3.8-rc4' into irq/core

Merge Linux 3.8-rc4 before pulling in new commits - we were on an old v3.7 base.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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);