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-rw-r--r--net/rds/tcp.c65
-rw-r--r--net/rds/tcp.h1
-rw-r--r--net/rds/tcp_listen.c13
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)