summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorYing Xue <ying.xue@windriver.com>2014-01-17 09:50:05 +0800
committerDavid S. Miller <davem@davemloft.net>2014-01-16 19:10:34 -0800
commit3f40504f7ee419eda0068e55e0ee2622e1fce40b (patch)
tree5a73408e3b982fa823210965fcc4277da18663d5
parent6398e23cdb1d807132c1d3d007d6b1ec87b511af (diff)
tipc: standardize sendmsg routine of connectionless socket
Comparing the behaviour of how to wait for events in TIPC sendmsg() with other stacks, the TIPC implementation might be perceived as different, and sometimes even incorrect. For instance, sk_sleep() and tport->congested variables associated with socket are exposed without socket lock protection while wait_event_interruptible_timeout() accesses them. So standardizing it with similar implementation in other stacks can help us correct these errors which the process of calling sendmsg() cannot be woken up event if an expected event arrive at socket or improperly woken up although the wake condition doesn't match. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/tipc/socket.c39
1 files changed, 29 insertions, 10 deletions
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 008f6fdf95c..3e019737e4b 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -567,6 +567,31 @@ 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
@@ -588,7 +613,7 @@ static int send_msg(struct kiocb *iocb, struct socket *sock,
struct tipc_port *tport = tipc_sk_port(sk);
struct sockaddr_tipc *dest = (struct sockaddr_tipc *)m->msg_name;
int needs_conn;
- long timeout_val;
+ long timeo;
int res = -EINVAL;
if (unlikely(!dest))
@@ -625,8 +650,7 @@ 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);
@@ -660,14 +684,9 @@ 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: