1 files changed, 197 insertions, 141 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index e741416d1d24..0ed0eaa62f29 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -55,9 +55,6 @@ struct tipc_sock {
 #define tipc_sk(sk) ((struct tipc_sock *)(sk))
 #define tipc_sk_port(sk) (tipc_sk(sk)->p)
 
-#define tipc_rx_ready(sock) (!skb_queue_empty(&sock->sk->sk_receive_queue) || \
-                        (sock->state == SS_DISCONNECTING))
-
 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);
@@ -73,8 +70,6 @@ static const struct proto_ops msg_ops;
 static struct proto tipc_proto;
 static struct proto tipc_proto_kern;
 
-static int sockets_enabled;
-
 /*
  * Revised TIPC socket locking policy:
  *
@@ -239,7 +234,6 @@ static int tipc_sk_create(struct net *net, struct socket *sock, int protocol,
 int tipc_sock_create_local(int type, struct socket **res)
 {
         int rc;
-        struct sock *sk;
 
         rc = sock_create_lite(AF_TIPC, type, 0, res);
         if (rc < 0) {
@@ -248,8 +242,6 @@ int tipc_sock_create_local(int type, struct socket **res)
         }
         tipc_sk_create(&init_net, *res, 0, 1);
 
-        sk = (*res)->sk;
-
         return 0;
 }
 
@@ -570,6 +562,31 @@ static int dest_name_check(struct sockaddr_tipc *dest, struct msghdr *m)
         return 0;
 }
 
+static int tipc_wait_for_sndmsg(struct socket *sock, long *timeo_p)
+{
+        struct sock *sk = sock->sk;
+        struct tipc_port *tport = tipc_sk_port(sk);
+        DEFINE_WAIT(wait);
+        int done;
+
+        do {
+                int err = sock_error(sk);
+                if (err)
+                        return err;
+                if (sock->state == SS_DISCONNECTING)
+                        return -EPIPE;
+                if (!*timeo_p)
+                        return -EAGAIN;
+                if (signal_pending(current))
+                        return sock_intr_errno(*timeo_p);
+
+                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+                done = sk_wait_event(sk, timeo_p, !tport->congested);
+                finish_wait(sk_sleep(sk), &wait);
+        } while (!done);
+        return 0;
+}
+
 /**
  * send_msg - send message in connectionless manner
  * @iocb: if NULL, indicates that socket lock is already held
@@ -589,9 +606,9 @@ static int send_msg(struct kiocb *iocb, struct socket *sock,
 {
         struct sock *sk = sock->sk;
         struct tipc_port *tport = tipc_sk_port(sk);
-        struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
+        DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
         int needs_conn;
-        long timeout_val;
+        long timeo;
         int res = -EINVAL;
 
         if (unlikely(!dest))
@@ -628,8 +645,7 @@ static int send_msg(struct kiocb *iocb, struct socket *sock,
                 reject_rx_queue(sk);
         }
 
-        timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
-
+        timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
         do {
                 if (dest->addrtype == TIPC_ADDR_NAME) {
                         res = dest_name_check(dest, m);
@@ -663,14 +679,9 @@ static int send_msg(struct kiocb *iocb, struct socket *sock,
                                 sock->state = SS_CONNECTING;
                         break;
                 }
-                if (timeout_val <= 0L) {
-                        res = timeout_val ? timeout_val : -EWOULDBLOCK;
+                res = tipc_wait_for_sndmsg(sock, &timeo);
+                if (res)
                         break;
-                }
-                release_sock(sk);
-                timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk),
-                                               !tport->congested, timeout_val);
-                lock_sock(sk);
         } while (1);
 
 exit:
@@ -679,6 +690,34 @@ exit:
         return res;
 }
 
+static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p)
+{
+        struct sock *sk = sock->sk;
+        struct tipc_port *tport = tipc_sk_port(sk);
+        DEFINE_WAIT(wait);
+        int done;
+
+        do {
+                int err = sock_error(sk);
+                if (err)
+                        return err;
+                if (sock->state == SS_DISCONNECTING)
+                        return -EPIPE;
+                else if (sock->state != SS_CONNECTED)
+                        return -ENOTCONN;
+                if (!*timeo_p)
+                        return -EAGAIN;
+                if (signal_pending(current))
+                        return sock_intr_errno(*timeo_p);
+
+                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+                done = sk_wait_event(sk, timeo_p,
+                                     (!tport->congested || !tport->connected));
+                finish_wait(sk_sleep(sk), &wait);
+        } while (!done);
+        return 0;
+}
+
 /**
  * send_packet - send a connection-oriented message
  * @iocb: if NULL, indicates that socket lock is already held
@@ -695,9 +734,9 @@ static int send_packet(struct kiocb *iocb, struct socket *sock,
 {
         struct sock *sk = sock->sk;
         struct tipc_port *tport = tipc_sk_port(sk);
-        struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
-        long timeout_val;
-        int res;
+        DECLARE_SOCKADDR(struct sockaddr_tipc *, dest, m->msg_name);
+        int res = -EINVAL;
+        long timeo;
 
         /* Handle implied connection establishment */
         if (unlikely(dest))
@@ -709,30 +748,24 @@ static int send_packet(struct kiocb *iocb, struct socket *sock,
         if (iocb)
                 lock_sock(sk);
 
-        timeout_val = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
+        if (unlikely(sock->state != SS_CONNECTED)) {
+                if (sock->state == SS_DISCONNECTING)
+                        res = -EPIPE;
+                else
+                        res = -ENOTCONN;
+                goto exit;
+        }
 
+        timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
         do {
-                if (unlikely(sock->state != SS_CONNECTED)) {
-                        if (sock->state == SS_DISCONNECTING)
-                                res = -EPIPE;
-                        else
-                                res = -ENOTCONN;
-                        break;
-                }
-
                 res = tipc_send(tport->ref, m->msg_iov, total_len);
                 if (likely(res != -ELINKCONG))
                         break;
-                if (timeout_val <= 0L) {
-                        res = timeout_val ? timeout_val : -EWOULDBLOCK;
+                res = tipc_wait_for_sndpkt(sock, &timeo);
+                if (res)
                         break;
-                }
-                release_sock(sk);
-                timeout_val = wait_event_interruptible_timeout(*sk_sleep(sk),
-                        (!tport->congested || !tport->connected), timeout_val);
-                lock_sock(sk);
         } while (1);
-
+exit:
         if (iocb)
                 release_sock(sk);
         return res;
@@ -770,16 +803,11 @@ static int send_stream(struct kiocb *iocb, struct socket *sock,
 
         /* Handle special cases where there is no connection */
         if (unlikely(sock->state != SS_CONNECTED)) {
-                if (sock->state == SS_UNCONNECTED) {
+                if (sock->state == SS_UNCONNECTED)
                         res = send_packet(NULL, sock, m, total_len);
-                        goto exit;
-                } else if (sock->state == SS_DISCONNECTING) {
-                        res = -EPIPE;
-                        goto exit;
-                } else {
-                        res = -ENOTCONN;
-                        goto exit;
-                }
+                else
+                        res = sock->state == SS_DISCONNECTING ? -EPIPE : -ENOTCONN;
+                goto exit;
         }
 
         if (unlikely(m->msg_name)) {
@@ -876,7 +904,7 @@ static int auto_connect(struct socket *sock, struct tipc_msg *msg)
  */
 static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg)
 {
-        struct sockaddr_tipc *addr = (struct sockaddr_tipc *)m->msg_name;
+        DECLARE_SOCKADDR(struct sockaddr_tipc *, addr, m->msg_name);
 
         if (addr) {
                 addr->family = AF_TIPC;
@@ -961,6 +989,37 @@ static int anc_data_recv(struct msghdr *m, struct tipc_msg *msg,
         return 0;
 }
 
+static int tipc_wait_for_rcvmsg(struct socket *sock, long timeo)
+{
+        struct sock *sk = sock->sk;
+        DEFINE_WAIT(wait);
+        int err;
+
+        for (;;) {
+                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+                if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
+                        if (sock->state == SS_DISCONNECTING) {
+                                err = -ENOTCONN;
+                                break;
+                        }
+                        release_sock(sk);
+                        timeo = schedule_timeout(timeo);
+                        lock_sock(sk);
+                }
+                err = 0;
+                if (!skb_queue_empty(&sk->sk_receive_queue))
+                        break;
+                err = sock_intr_errno(timeo);
+                if (signal_pending(current))
+                        break;
+                err = -EAGAIN;
+                if (!timeo)
+                        break;
+        }
+        finish_wait(sk_sleep(sk), &wait);
+        return err;
+}
+
 /**
  * recv_msg - receive packet-oriented message
  * @iocb: (unused)
@@ -980,7 +1039,7 @@ static int recv_msg(struct kiocb *iocb, struct socket *sock,
         struct tipc_port *tport = tipc_sk_port(sk);
         struct sk_buff *buf;
         struct tipc_msg *msg;
-        long timeout;
+        long timeo;
         unsigned int sz;
         u32 err;
         int res;
@@ -996,25 +1055,13 @@ static int recv_msg(struct kiocb *iocb, struct socket *sock,
                 goto exit;
         }
 
-        timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+        timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
 restart:
 
         /* Look for a message in receive queue; wait if necessary */
-        while (skb_queue_empty(&sk->sk_receive_queue)) {
-                if (sock->state == SS_DISCONNECTING) {
-                        res = -ENOTCONN;
-                        goto exit;
-                }
-                if (timeout <= 0L) {
-                        res = timeout ? timeout : -EWOULDBLOCK;
-                        goto exit;
-                }
-                release_sock(sk);
-                timeout = wait_event_interruptible_timeout(*sk_sleep(sk),
-                                                           tipc_rx_ready(sock),
-                                                           timeout);
-                lock_sock(sk);
-        }
+        res = tipc_wait_for_rcvmsg(sock, timeo);
+        if (res)
+                goto exit;
 
         /* Look at first message in receive queue */
         buf = skb_peek(&sk->sk_receive_queue);
@@ -1086,7 +1133,7 @@ static int recv_stream(struct kiocb *iocb, struct socket *sock,
         struct tipc_port *tport = tipc_sk_port(sk);
         struct sk_buff *buf;
         struct tipc_msg *msg;
-        long timeout;
+        long timeo;
         unsigned int sz;
         int sz_to_copy, target, needed;
         int sz_copied = 0;
@@ -1099,31 +1146,19 @@ static int recv_stream(struct kiocb *iocb, struct socket *sock,
 
         lock_sock(sk);
 
-        if (unlikely((sock->state == SS_UNCONNECTED))) {
+        if (unlikely(sock->state == SS_UNCONNECTED)) {
                 res = -ENOTCONN;
                 goto exit;
         }
 
         target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
-        timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+        timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
 
 restart:
         /* Look for a message in receive queue; wait if necessary */
-        while (skb_queue_empty(&sk->sk_receive_queue)) {
-                if (sock->state == SS_DISCONNECTING) {
-                        res = -ENOTCONN;
-                        goto exit;
-                }
-                if (timeout <= 0L) {
-                        res = timeout ? timeout : -EWOULDBLOCK;
-                        goto exit;
-                }
-                release_sock(sk);
-                timeout = wait_event_interruptible_timeout(*sk_sleep(sk),
-                                                           tipc_rx_ready(sock),
-                                                           timeout);
-                lock_sock(sk);
-        }
+        res = tipc_wait_for_rcvmsg(sock, timeo);
+        if (res)
+                goto exit;
 
         /* Look at first message in receive queue */
         buf = skb_peek(&sk->sk_receive_queue);
@@ -1327,14 +1362,12 @@ static u32 filter_connect(struct tipc_sock *tsock, struct sk_buff **buf)
 static unsigned int rcvbuf_limit(struct sock *sk, struct sk_buff *buf)
 {
         struct tipc_msg *msg = buf_msg(buf);
-        unsigned int limit;
 
         if (msg_connected(msg))
-                limit = sysctl_tipc_rmem[2];
-        else
-                limit = sk->sk_rcvbuf >> TIPC_CRITICAL_IMPORTANCE <<
-                        msg_importance(msg);
-        return limit;
+                return sysctl_tipc_rmem[2];
+
+        return sk->sk_rcvbuf >> TIPC_CRITICAL_IMPORTANCE <<
+                msg_importance(msg);
 }
 
 /**
@@ -1448,6 +1481,28 @@ static void wakeupdispatch(struct tipc_port *tport)
         sk->sk_write_space(sk);
 }
 
+static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
+{
+        struct sock *sk = sock->sk;
+        DEFINE_WAIT(wait);
+        int done;
+
+        do {
+                int err = sock_error(sk);
+                if (err)
+                        return err;
+                if (!*timeo_p)
+                        return -ETIMEDOUT;
+                if (signal_pending(current))
+                        return sock_intr_errno(*timeo_p);
+
+                prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+                done = sk_wait_event(sk, timeo_p, sock->state != SS_CONNECTING);
+                finish_wait(sk_sleep(sk), &wait);
+        } while (!done);
+        return 0;
+}
+
 /**
  * connect - establish a connection to another TIPC port
  * @sock: socket structure
@@ -1463,7 +1518,8 @@ 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,};
-        unsigned int timeout;
+        long timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout;
+        socket_state previous;
         int res;
 
         lock_sock(sk);
@@ -1485,8 +1541,7 @@ static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
                 goto exit;
         }
 
-        timeout = (flags & O_NONBLOCK) ? 0 : tipc_sk(sk)->conn_timeout;
-
+        previous = sock->state;
         switch (sock->state) {
         case SS_UNCONNECTED:
                 /* Send a 'SYN-' to destination */
@@ -1508,43 +1563,22 @@ static int connect(struct socket *sock, struct sockaddr *dest, int destlen,
                  * case is EINPROGRESS, rather than EALREADY.
                  */
                 res = -EINPROGRESS;
-                break;
         case SS_CONNECTING:
-                res = -EALREADY;
+                if (previous == SS_CONNECTING)
+                        res = -EALREADY;
+                if (!timeout)
+                        goto exit;
+                timeout = msecs_to_jiffies(timeout);
+                /* Wait until an 'ACK' or 'RST' arrives, or a timeout occurs */
+                res = tipc_wait_for_connect(sock, &timeout);
                 break;
         case SS_CONNECTED:
                 res = -EISCONN;
                 break;
         default:
                 res = -EINVAL;
-                goto exit;
-        }
-
-        if (sock->state == SS_CONNECTING) {
-                if (!timeout)
-                        goto exit;
-
-                /* 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
-                                ; /* leave "res" unchanged */
-                        goto exit;
-                }
+                break;
         }
-
-        if (unlikely(sock->state == SS_DISCONNECTING))
-                res = sock_error(sk);
-        else
-                res = 0;
-
 exit:
         release_sock(sk);
         return res;
@@ -1575,6 +1609,42 @@ static int listen(struct socket *sock, int len)
         return res;
 }
 
+static int tipc_wait_for_accept(struct socket *sock, long timeo)
+{
+        struct sock *sk = sock->sk;
+        DEFINE_WAIT(wait);
+        int err;
+
+        /* True wake-one mechanism for incoming connections: only
+         * one process gets woken up, not the 'whole herd'.
+         * Since we do not 'race & poll' for established sockets
+         * anymore, the common case will execute the loop only once.
+        */
+        for (;;) {
+                prepare_to_wait_exclusive(sk_sleep(sk), &wait,
+                                          TASK_INTERRUPTIBLE);
+                if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
+                        release_sock(sk);
+                        timeo = schedule_timeout(timeo);
+                        lock_sock(sk);
+                }
+                err = 0;
+                if (!skb_queue_empty(&sk->sk_receive_queue))
+                        break;
+                err = -EINVAL;
+                if (sock->state != SS_LISTENING)
+                        break;
+                err = sock_intr_errno(timeo);
+                if (signal_pending(current))
+                        break;
+                err = -EAGAIN;
+                if (!timeo)
+                        break;
+        }
+        finish_wait(sk_sleep(sk), &wait);
+        return err;
+}
+
 /**
  * accept - wait for connection request
  * @sock: listening socket
@@ -1591,7 +1661,7 @@ static int accept(struct socket *sock, struct socket *new_sock, int flags)
         struct tipc_port *new_tport;
         struct tipc_msg *msg;
         u32 new_ref;
-
+        long timeo;
         int res;
 
         lock_sock(sk);
@@ -1601,18 +1671,10 @@ static int accept(struct socket *sock, struct socket *new_sock, int flags)
                 goto exit;
         }
 
-        while (skb_queue_empty(&sk->sk_receive_queue)) {
-                if (flags & O_NONBLOCK) {
-                        res = -EWOULDBLOCK;
-                        goto exit;
-                }
-                release_sock(sk);
-                res = wait_event_interruptible(*sk_sleep(sk),
-                                (!skb_queue_empty(&sk->sk_receive_queue)));
-                lock_sock(sk);
-                if (res)
-                        goto exit;
-        }
+        timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
+        res = tipc_wait_for_accept(sock, timeo);
+        if (res)
+                goto exit;
 
         buf = skb_peek(&sk->sk_receive_queue);
 
@@ -1963,8 +2025,6 @@ int tipc_socket_init(void)
                 proto_unregister(&tipc_proto);
                 goto out;
         }
-
-        sockets_enabled = 1;
  out:
         return res;
 }
@@ -1974,10 +2034,6 @@ int tipc_socket_init(void)
  */
 void tipc_socket_stop(void)
 {
-        if (!sockets_enabled)
-                return;
-
-        sockets_enabled = 0;
         sock_unregister(tipc_family_ops.family);
         proto_unregister(&tipc_proto);
 }