Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:

 1) Unified UDP encapsulation offload methods for drivers, from
    Alexander Duyck.

 2) Make DSA binding more sane, from Andrew Lunn.

 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli.

 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar.

 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX
    packets as soon as the device sees them, with the option to mirror
    the packet on TX via the same interface.  From Brenden Blanco and
    others.

 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet.

 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli.

 8) Simplify netlink conntrack entry layout, from Florian Westphal.

 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido
    Schimmel, Yotam Gigi, and Jiri Pirko.

10) Add SKB array infrastructure and convert tun and macvtap over to it.
    From Michael S Tsirkin and Jason Wang.

11) Support qdisc packet injection in pktgen, from John Fastabend.

12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy.

13) Add NV congestion control support to TCP, from Lawrence Brakmo.

14) Add GSO support to SCTP, from Marcelo Ricardo Leitner.

15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni.

16) Support MPLS over IPV4, from Simon Horman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits)
  xgene: Fix build warning with ACPI disabled.
  be2net: perform temperature query in adapter regardless of its interface state
  l2tp: Correctly return -EBADF from pppol2tp_getname.
  net/mlx5_core/health: Remove deprecated create_singlethread_workqueue
  net: ipmr/ip6mr: update lastuse on entry change
  macsec: ensure rx_sa is set when validation is disabled
  tipc: dump monitor attributes
  tipc: add a function to get the bearer name
  tipc: get monitor threshold for the cluster
  tipc: make cluster size threshold for monitoring configurable
  tipc: introduce constants for tipc address validation
  net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update()
  MAINTAINERS: xgene: Add driver and documentation path
  Documentation: dtb: xgene: Add MDIO node
  dtb: xgene: Add MDIO node
  drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset
  drivers: net: xgene: Use exported functions
  drivers: net: xgene: Enable MDIO driver
  drivers: net: xgene: Add backward compatibility
  drivers: net: phy: xgene: Add MDIO driver
  ...

1 files changed, 230 insertions, 0 deletions

diff --git a/net/rxrpc/conn_service.c b/net/rxrpc/conn_service.c
new file mode 100644
index 000000000000..fd9027ccba8f
--- /dev/null
+++ b/net/rxrpc/conn_service.c
@@ -0,0 +1,230 @@
+/* Service connection management
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/slab.h>
+#include "ar-internal.h"
+
+/*
+ * Find a service connection under RCU conditions.
+ *
+ * We could use a hash table, but that is subject to bucket stuffing by an
+ * attacker as the client gets to pick the epoch and cid values and would know
+ * the hash function.  So, instead, we use a hash table for the peer and from
+ * that an rbtree to find the service connection.  Under ordinary circumstances
+ * it might be slower than a large hash table, but it is at least limited in
+ * depth.
+ */
+struct rxrpc_connection *rxrpc_find_service_conn_rcu(struct rxrpc_peer *peer,
+						     struct sk_buff *skb)
+{
+	struct rxrpc_connection *conn = NULL;
+	struct rxrpc_conn_proto k;
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rb_node *p;
+	unsigned int seq = 0;
+
+	k.epoch	= sp->hdr.epoch;
+	k.cid	= sp->hdr.cid & RXRPC_CIDMASK;
+
+	do {
+		/* Unfortunately, rbtree walking doesn't give reliable results
+		 * under just the RCU read lock, so we have to check for
+		 * changes.
+		 */
+		read_seqbegin_or_lock(&peer->service_conn_lock, &seq);
+
+		p = rcu_dereference_raw(peer->service_conns.rb_node);
+		while (p) {
+			conn = rb_entry(p, struct rxrpc_connection, service_node);
+
+			if (conn->proto.index_key < k.index_key)
+				p = rcu_dereference_raw(p->rb_left);
+			else if (conn->proto.index_key > k.index_key)
+				p = rcu_dereference_raw(p->rb_right);
+			else
+				goto done;
+			conn = NULL;
+		}
+	} while (need_seqretry(&peer->service_conn_lock, seq));
+
+done:
+	done_seqretry(&peer->service_conn_lock, seq);
+	_leave(" = %d", conn ? conn->debug_id : -1);
+	return conn;
+}
+
+/*
+ * Insert a service connection into a peer's tree, thereby making it a target
+ * for incoming packets.
+ */
+static struct rxrpc_connection *
+rxrpc_publish_service_conn(struct rxrpc_peer *peer,
+			   struct rxrpc_connection *conn)
+{
+	struct rxrpc_connection *cursor = NULL;
+	struct rxrpc_conn_proto k = conn->proto;
+	struct rb_node **pp, *parent;
+
+	write_seqlock_bh(&peer->service_conn_lock);
+
+	pp = &peer->service_conns.rb_node;
+	parent = NULL;
+	while (*pp) {
+		parent = *pp;
+		cursor = rb_entry(parent,
+				  struct rxrpc_connection, service_node);
+
+		if (cursor->proto.index_key < k.index_key)
+			pp = &(*pp)->rb_left;
+		else if (cursor->proto.index_key > k.index_key)
+			pp = &(*pp)->rb_right;
+		else
+			goto found_extant_conn;
+	}
+
+	rb_link_node_rcu(&conn->service_node, parent, pp);
+	rb_insert_color(&conn->service_node, &peer->service_conns);
+conn_published:
+	set_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags);
+	write_sequnlock_bh(&peer->service_conn_lock);
+	_leave(" = %d [new]", conn->debug_id);
+	return conn;
+
+found_extant_conn:
+	if (atomic_read(&cursor->usage) == 0)
+		goto replace_old_connection;
+	write_sequnlock_bh(&peer->service_conn_lock);
+	/* We should not be able to get here.  rxrpc_incoming_connection() is
+	 * called in a non-reentrant context, so there can't be a race to
+	 * insert a new connection.
+	 */
+	BUG();
+
+replace_old_connection:
+	/* The old connection is from an outdated epoch. */
+	_debug("replace conn");
+	rb_replace_node_rcu(&cursor->service_node,
+			    &conn->service_node,
+			    &peer->service_conns);
+	clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &cursor->flags);
+	goto conn_published;
+}
+
+/*
+ * get a record of an incoming connection
+ */
+struct rxrpc_connection *rxrpc_incoming_connection(struct rxrpc_local *local,
+						   struct sockaddr_rxrpc *srx,
+						   struct sk_buff *skb)
+{
+	struct rxrpc_connection *conn;
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxrpc_peer *peer;
+	const char *new = "old";
+
+	_enter("");
+
+	peer = rxrpc_lookup_peer(local, srx, GFP_NOIO);
+	if (!peer) {
+		_debug("no peer");
+		return ERR_PTR(-EBUSY);
+	}
+
+	ASSERT(sp->hdr.flags & RXRPC_CLIENT_INITIATED);
+
+	rcu_read_lock();
+	peer = rxrpc_lookup_peer_rcu(local, srx);
+	if (peer) {
+		conn = rxrpc_find_service_conn_rcu(peer, skb);
+		if (conn) {
+			if (sp->hdr.securityIndex != conn->security_ix)
+				goto security_mismatch_rcu;
+			if (rxrpc_get_connection_maybe(conn))
+				goto found_extant_connection_rcu;
+
+			/* The conn has expired but we can't remove it without
+			 * the appropriate lock, so we attempt to replace it
+			 * when we have a new candidate.
+			 */
+		}
+
+		if (!rxrpc_get_peer_maybe(peer))
+			peer = NULL;
+	}
+	rcu_read_unlock();
+
+	if (!peer) {
+		peer = rxrpc_lookup_peer(local, srx, GFP_NOIO);
+		if (!peer)
+			goto enomem;
+	}
+
+	/* We don't have a matching record yet. */
+	conn = rxrpc_alloc_connection(GFP_NOIO);
+	if (!conn)
+		goto enomem_peer;
+
+	conn->proto.epoch	= sp->hdr.epoch;
+	conn->proto.cid		= sp->hdr.cid & RXRPC_CIDMASK;
+	conn->params.local	= local;
+	conn->params.peer	= peer;
+	conn->params.service_id	= sp->hdr.serviceId;
+	conn->security_ix	= sp->hdr.securityIndex;
+	conn->out_clientflag	= 0;
+	conn->state		= RXRPC_CONN_SERVICE;
+	if (conn->params.service_id)
+		conn->state	= RXRPC_CONN_SERVICE_UNSECURED;
+
+	rxrpc_get_local(local);
+
+	write_lock(&rxrpc_connection_lock);
+	list_add_tail(&conn->link, &rxrpc_connections);
+	write_unlock(&rxrpc_connection_lock);
+
+	/* Make the connection a target for incoming packets. */
+	rxrpc_publish_service_conn(peer, conn);
+
+	new = "new";
+
+success:
+	_net("CONNECTION %s %d {%x}", new, conn->debug_id, conn->proto.cid);
+	_leave(" = %p {u=%d}", conn, atomic_read(&conn->usage));
+	return conn;
+
+found_extant_connection_rcu:
+	rcu_read_unlock();
+	goto success;
+
+security_mismatch_rcu:
+	rcu_read_unlock();
+	_leave(" = -EKEYREJECTED");
+	return ERR_PTR(-EKEYREJECTED);
+
+enomem_peer:
+	rxrpc_put_peer(peer);
+enomem:
+	_leave(" = -ENOMEM");
+	return ERR_PTR(-ENOMEM);
+}
+
+/*
+ * Remove the service connection from the peer's tree, thereby removing it as a
+ * target for incoming packets.
+ */
+void rxrpc_unpublish_service_conn(struct rxrpc_connection *conn)
+{
+	struct rxrpc_peer *peer = conn->params.peer;
+
+	write_seqlock_bh(&peer->service_conn_lock);
+	if (test_and_clear_bit(RXRPC_CONN_IN_SERVICE_CONNS, &conn->flags))
+		rb_erase(&conn->service_node, &peer->service_conns);
+	write_sequnlock_bh(&peer->service_conn_lock);
+}