diff options
Diffstat (limited to 'net/rds/tcp_listen.c')
| -rw-r--r-- | net/rds/tcp_listen.c | 63 |
1 files changed, 43 insertions, 20 deletions
diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 0936a4a32b47..4bf4befe5066 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -76,7 +76,12 @@ int rds_tcp_accept_one(struct socket *sock) struct rds_connection *conn; int ret; struct inet_sock *inet; - struct rds_tcp_connection *rs_tcp; + struct rds_tcp_connection *rs_tcp = NULL; + int conn_state; + struct sock *nsk; + + if (!sock) /* module unload or netns delete in progress */ + return -ENETUNREACH; ret = sock_create_kern(sock_net(sock->sk), sock->sk->sk_family, sock->sk->sk_type, sock->sk->sk_protocol, @@ -115,28 +120,46 @@ int rds_tcp_accept_one(struct socket *sock) * rds_tcp_state_change() will do that cleanup */ rs_tcp = (struct rds_tcp_connection *)conn->c_transport_data; - if (rs_tcp->t_sock && - ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr)) { - struct sock *nsk = new_sock->sk; - - nsk->sk_user_data = NULL; - nsk->sk_prot->disconnect(nsk, 0); - tcp_done(nsk); - new_sock = NULL; - ret = 0; - goto out; - } else if (rs_tcp->t_sock) { - rds_tcp_restore_callbacks(rs_tcp->t_sock, rs_tcp); - conn->c_outgoing = 0; - } - rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING); + mutex_lock(&rs_tcp->t_conn_lock); + conn_state = rds_conn_state(conn); + if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_UP) + goto rst_nsk; + if (rs_tcp->t_sock) { + /* Need to resolve a duelling SYN between peers. + * We have an outstanding SYN to this peer, which may + * potentially have transitioned to the RDS_CONN_UP state, + * so we must quiesce any send threads before resetting + * c_transport_data. + */ + if (ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr) || + !conn->c_outgoing) { + goto rst_nsk; + } else { + atomic_set(&conn->c_state, RDS_CONN_CONNECTING); + wait_event(conn->c_waitq, + !test_bit(RDS_IN_XMIT, &conn->c_flags)); + rds_tcp_restore_callbacks(rs_tcp->t_sock, rs_tcp); + conn->c_outgoing = 0; + } + } rds_tcp_set_callbacks(new_sock, conn); - rds_connect_complete(conn); + rds_connect_complete(conn); /* marks RDS_CONN_UP */ + new_sock = NULL; + ret = 0; + goto out; +rst_nsk: + /* reset the newly returned accept sock and bail */ + nsk = new_sock->sk; + rds_tcp_stats_inc(s_tcp_listen_closed_stale); + nsk->sk_user_data = NULL; + nsk->sk_prot->disconnect(nsk, 0); + tcp_done(nsk); new_sock = NULL; ret = 0; - out: + if (rs_tcp) + mutex_unlock(&rs_tcp->t_conn_lock); if (new_sock) sock_release(new_sock); return ret; @@ -148,7 +171,7 @@ void rds_tcp_listen_data_ready(struct sock *sk) rdsdebug("listen data ready sk %p\n", sk); - read_lock(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); ready = sk->sk_user_data; if (!ready) { /* check for teardown race */ ready = sk->sk_data_ready; @@ -165,7 +188,7 @@ void rds_tcp_listen_data_ready(struct sock *sk) rds_tcp_accept_work(sk); out: - read_unlock(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); ready(sk); } |