net: Add Open vSwitch kernel components.

Open vSwitch is a multilayer Ethernet switch targeted at virtualized
environments.  In addition to supporting a variety of features
expected in a traditional hardware switch, it enables fine-grained
programmatic extension and flow-based control of the network.
This control is useful in a wide variety of applications but is
particularly important in multi-server virtualization deployments,
which are often characterized by highly dynamic endpoints and the need
to maintain logical abstractions for multiple tenants.

The Open vSwitch datapath provides an in-kernel fast path for packet
forwarding.  It is complemented by a userspace daemon, ovs-vswitchd,
which is able to accept configuration from a variety of sources and
translate it into packet processing rules.

See http://openvswitch.org for more information and userspace
utilities.

Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 125 insertions, 0 deletions

diff --git a/net/openvswitch/datapath.h b/net/openvswitch/datapath.h
new file mode 100644
index 000000000000..5b9f884b7055
--- /dev/null
+++ b/net/openvswitch/datapath.h
@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2007-2011 Nicira Networks.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#ifndef DATAPATH_H
+#define DATAPATH_H 1
+
+#include <asm/page.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/u64_stats_sync.h>
+#include <linux/version.h>
+
+#include "flow.h"
+
+struct vport;
+
+#define DP_MAX_PORTS 1024
+#define SAMPLE_ACTION_DEPTH 3
+
+/**
+ * struct dp_stats_percpu - per-cpu packet processing statistics for a given
+ * datapath.
+ * @n_hit: Number of received packets for which a matching flow was found in
+ * the flow table.
+ * @n_miss: Number of received packets that had no matching flow in the flow
+ * table.  The sum of @n_hit and @n_miss is the number of packets that have
+ * been received by the datapath.
+ * @n_lost: Number of received packets that had no matching flow in the flow
+ * table that could not be sent to userspace (normally due to an overflow in
+ * one of the datapath's queues).
+ */
+struct dp_stats_percpu {
+	u64 n_hit;
+	u64 n_missed;
+	u64 n_lost;
+	struct u64_stats_sync sync;
+};
+
+/**
+ * struct datapath - datapath for flow-based packet switching
+ * @rcu: RCU callback head for deferred destruction.
+ * @list_node: Element in global 'dps' list.
+ * @n_flows: Number of flows currently in flow table.
+ * @table: Current flow table.  Protected by genl_lock and RCU.
+ * @ports: Map from port number to &struct vport.  %OVSP_LOCAL port
+ * always exists, other ports may be %NULL.  Protected by RTNL and RCU.
+ * @port_list: List of all ports in @ports in arbitrary order.  RTNL required
+ * to iterate or modify.
+ * @stats_percpu: Per-CPU datapath statistics.
+ *
+ * Context: See the comment on locking at the top of datapath.c for additional
+ * locking information.
+ */
+struct datapath {
+	struct rcu_head rcu;
+	struct list_head list_node;
+
+	/* Flow table. */
+	struct flow_table __rcu *table;
+
+	/* Switch ports. */
+	struct vport __rcu *ports[DP_MAX_PORTS];
+	struct list_head port_list;
+
+	/* Stats. */
+	struct dp_stats_percpu __percpu *stats_percpu;
+};
+
+/**
+ * struct ovs_skb_cb - OVS data in skb CB
+ * @flow: The flow associated with this packet.  May be %NULL if no flow.
+ */
+struct ovs_skb_cb {
+	struct sw_flow		*flow;
+};
+#define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
+
+/**
+ * struct dp_upcall - metadata to include with a packet to send to userspace
+ * @cmd: One of %OVS_PACKET_CMD_*.
+ * @key: Becomes %OVS_PACKET_ATTR_KEY.  Must be nonnull.
+ * @userdata: If nonnull, its u64 value is extracted and passed to userspace as
+ * %OVS_PACKET_ATTR_USERDATA.
+ * @pid: Netlink PID to which packet should be sent.  If @pid is 0 then no
+ * packet is sent and the packet is accounted in the datapath's @n_lost
+ * counter.
+ */
+struct dp_upcall_info {
+	u8 cmd;
+	const struct sw_flow_key *key;
+	const struct nlattr *userdata;
+	u32 pid;
+};
+
+extern struct notifier_block ovs_dp_device_notifier;
+extern struct genl_multicast_group ovs_dp_vport_multicast_group;
+
+void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
+void ovs_dp_detach_port(struct vport *);
+int ovs_dp_upcall(struct datapath *, struct sk_buff *,
+		  const struct dp_upcall_info *);
+
+const char *ovs_dp_name(const struct datapath *dp);
+struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq,
+					 u8 cmd);
+
+int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb);
+#endif /* datapath.h */