diff options
| -rw-r--r-- | net/rds/tcp.c | 65 | ||||
| -rw-r--r-- | net/rds/tcp.h | 1 | ||||
| -rw-r--r-- | net/rds/tcp_listen.c | 13 |
3 files changed, 67 insertions, 12 deletions
diff --git a/net/rds/tcp.c b/net/rds/tcp.c index 86187dad1440..8faa0b1ae39d 100644 --- a/net/rds/tcp.c +++ b/net/rds/tcp.c @@ -126,9 +126,68 @@ void rds_tcp_restore_callbacks(struct socket *sock, } /* - * This is the only path that sets tc->t_sock. Send and receive trust that - * it is set. The RDS_CONN_UP bit protects those paths from being - * called while it isn't set. + * rds_tcp_reset_callbacks() switches the to the new sock and + * returns the existing tc->t_sock. + * + * The only functions that set tc->t_sock are rds_tcp_set_callbacks + * and rds_tcp_reset_callbacks. Send and receive trust that + * it is set. The absence of RDS_CONN_UP bit protects those paths + * from being called while it isn't set. + */ +void rds_tcp_reset_callbacks(struct socket *sock, + struct rds_connection *conn) +{ + struct rds_tcp_connection *tc = conn->c_transport_data; + struct socket *osock = tc->t_sock; + + if (!osock) + goto newsock; + + /* 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. We quiesce these threads by setting + * cp_state to something other than RDS_CONN_UP, and then + * waiting for any existing threads in rds_send_xmit to + * complete release_in_xmit(). (Subsequent threads entering + * rds_send_xmit() will bail on !rds_conn_up(). + */ + lock_sock(osock->sk); + /* reset receive side state for rds_tcp_data_recv() for osock */ + if (tc->t_tinc) { + rds_inc_put(&tc->t_tinc->ti_inc); + tc->t_tinc = NULL; + } + tc->t_tinc_hdr_rem = sizeof(struct rds_header); + tc->t_tinc_data_rem = 0; + tc->t_sock = NULL; + + write_lock_bh(&osock->sk->sk_callback_lock); + + osock->sk->sk_user_data = NULL; + osock->sk->sk_data_ready = tc->t_orig_data_ready; + osock->sk->sk_write_space = tc->t_orig_write_space; + osock->sk->sk_state_change = tc->t_orig_state_change; + write_unlock_bh(&osock->sk->sk_callback_lock); + release_sock(osock->sk); + sock_release(osock); +newsock: + lock_sock(sock->sk); + write_lock_bh(&sock->sk->sk_callback_lock); + tc->t_sock = sock; + sock->sk->sk_user_data = conn; + sock->sk->sk_data_ready = rds_tcp_data_ready; + sock->sk->sk_write_space = rds_tcp_write_space; + sock->sk->sk_state_change = rds_tcp_state_change; + + write_unlock_bh(&sock->sk->sk_callback_lock); + release_sock(sock->sk); +} + +/* Add tc to rds_tcp_tc_list and set tc->t_sock. See comments + * above rds_tcp_reset_callbacks for notes about synchronization + * with data path */ void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn) { diff --git a/net/rds/tcp.h b/net/rds/tcp.h index 41c228300525..ec0602b0dc24 100644 --- a/net/rds/tcp.h +++ b/net/rds/tcp.h @@ -50,6 +50,7 @@ struct rds_tcp_statistics { void rds_tcp_tune(struct socket *sock); void rds_tcp_nonagle(struct socket *sock); void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn); +void rds_tcp_reset_callbacks(struct socket *sock, struct rds_connection *conn); void rds_tcp_restore_callbacks(struct socket *sock, struct rds_tcp_connection *tc); u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc); diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 4bf4befe5066..d9fe53675d95 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -78,7 +78,6 @@ int rds_tcp_accept_one(struct socket *sock) struct inet_sock *inet; struct rds_tcp_connection *rs_tcp = NULL; int conn_state; - struct sock *nsk; if (!sock) /* module unload or netns delete in progress */ return -ENETUNREACH; @@ -139,23 +138,19 @@ int rds_tcp_accept_one(struct socket *sock) 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); + rds_tcp_reset_callbacks(new_sock, conn); conn->c_outgoing = 0; } + } else { + rds_tcp_set_callbacks(new_sock, conn); } - rds_tcp_set_callbacks(new_sock, 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; + kernel_sock_shutdown(new_sock, SHUT_RDWR); ret = 0; out: if (rs_tcp) |