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>
diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h
new file mode 100644
index 0000000..1960962
--- /dev/null
+++ b/net/openvswitch/vport.h
@@ -0,0 +1,205 @@
+/*
+ * 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 VPORT_H
+#define VPORT_H 1
+
+#include <linux/list.h>
+#include <linux/openvswitch.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/u64_stats_sync.h>
+
+#include "datapath.h"
+
+struct vport;
+struct vport_parms;
+
+/* The following definitions are for users of the vport subsytem: */
+
+int ovs_vport_init(void);
+void ovs_vport_exit(void);
+
+struct vport *ovs_vport_add(const struct vport_parms *);
+void ovs_vport_del(struct vport *);
+
+struct vport *ovs_vport_locate(const char *name);
+
+void ovs_vport_get_stats(struct vport *, struct ovs_vport_stats *);
+
+int ovs_vport_set_options(struct vport *, struct nlattr *options);
+int ovs_vport_get_options(const struct vport *, struct sk_buff *);
+
+int ovs_vport_send(struct vport *, struct sk_buff *);
+
+/* The following definitions are for implementers of vport devices: */
+
+struct vport_percpu_stats {
+	u64 rx_bytes;
+	u64 rx_packets;
+	u64 tx_bytes;
+	u64 tx_packets;
+	struct u64_stats_sync sync;
+};
+
+struct vport_err_stats {
+	u64 rx_dropped;
+	u64 rx_errors;
+	u64 tx_dropped;
+	u64 tx_errors;
+};
+
+/**
+ * struct vport - one port within a datapath
+ * @rcu: RCU callback head for deferred destruction.
+ * @port_no: Index into @dp's @ports array.
+ * @dp: Datapath to which this port belongs.
+ * @node: Element in @dp's @port_list.
+ * @upcall_pid: The Netlink port to use for packets received on this port that
+ * miss the flow table.
+ * @hash_node: Element in @dev_table hash table in vport.c.
+ * @ops: Class structure.
+ * @percpu_stats: Points to per-CPU statistics used and maintained by vport
+ * @stats_lock: Protects @err_stats;
+ * @err_stats: Points to error statistics used and maintained by vport
+ */
+struct vport {
+	struct rcu_head rcu;
+	u16 port_no;
+	struct datapath	*dp;
+	struct list_head node;
+	u32 upcall_pid;
+
+	struct hlist_node hash_node;
+	const struct vport_ops *ops;
+
+	struct vport_percpu_stats __percpu *percpu_stats;
+
+	spinlock_t stats_lock;
+	struct vport_err_stats err_stats;
+};
+
+/**
+ * struct vport_parms - parameters for creating a new vport
+ *
+ * @name: New vport's name.
+ * @type: New vport's type.
+ * @options: %OVS_VPORT_ATTR_OPTIONS attribute from Netlink message, %NULL if
+ * none was supplied.
+ * @dp: New vport's datapath.
+ * @port_no: New vport's port number.
+ */
+struct vport_parms {
+	const char *name;
+	enum ovs_vport_type type;
+	struct nlattr *options;
+
+	/* For ovs_vport_alloc(). */
+	struct datapath *dp;
+	u16 port_no;
+	u32 upcall_pid;
+};
+
+/**
+ * struct vport_ops - definition of a type of virtual port
+ *
+ * @type: %OVS_VPORT_TYPE_* value for this type of virtual port.
+ * @create: Create a new vport configured as specified.  On success returns
+ * a new vport allocated with ovs_vport_alloc(), otherwise an ERR_PTR() value.
+ * @destroy: Destroys a vport.  Must call vport_free() on the vport but not
+ * before an RCU grace period has elapsed.
+ * @set_options: Modify the configuration of an existing vport.  May be %NULL
+ * if modification is not supported.
+ * @get_options: Appends vport-specific attributes for the configuration of an
+ * existing vport to a &struct sk_buff.  May be %NULL for a vport that does not
+ * have any configuration.
+ * @get_name: Get the device's name.
+ * @get_config: Get the device's configuration.
+ * @get_ifindex: Get the system interface index associated with the device.
+ * May be null if the device does not have an ifindex.
+ * @send: Send a packet on the device.  Returns the length of the packet sent.
+ */
+struct vport_ops {
+	enum ovs_vport_type type;
+
+	/* Called with RTNL lock. */
+	struct vport *(*create)(const struct vport_parms *);
+	void (*destroy)(struct vport *);
+
+	int (*set_options)(struct vport *, struct nlattr *);
+	int (*get_options)(const struct vport *, struct sk_buff *);
+
+	/* Called with rcu_read_lock or RTNL lock. */
+	const char *(*get_name)(const struct vport *);
+	void (*get_config)(const struct vport *, void *);
+	int (*get_ifindex)(const struct vport *);
+
+	int (*send)(struct vport *, struct sk_buff *);
+};
+
+enum vport_err_type {
+	VPORT_E_RX_DROPPED,
+	VPORT_E_RX_ERROR,
+	VPORT_E_TX_DROPPED,
+	VPORT_E_TX_ERROR,
+};
+
+struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *,
+			      const struct vport_parms *);
+void ovs_vport_free(struct vport *);
+
+#define VPORT_ALIGN 8
+
+/**
+ *	vport_priv - access private data area of vport
+ *
+ * @vport: vport to access
+ *
+ * If a nonzero size was passed in priv_size of vport_alloc() a private data
+ * area was allocated on creation.  This allows that area to be accessed and
+ * used for any purpose needed by the vport implementer.
+ */
+static inline void *vport_priv(const struct vport *vport)
+{
+	return (u8 *)vport + ALIGN(sizeof(struct vport), VPORT_ALIGN);
+}
+
+/**
+ *	vport_from_priv - lookup vport from private data pointer
+ *
+ * @priv: Start of private data area.
+ *
+ * It is sometimes useful to translate from a pointer to the private data
+ * area to the vport, such as in the case where the private data pointer is
+ * the result of a hash table lookup.  @priv must point to the start of the
+ * private data area.
+ */
+static inline struct vport *vport_from_priv(const void *priv)
+{
+	return (struct vport *)(priv - ALIGN(sizeof(struct vport), VPORT_ALIGN));
+}
+
+void ovs_vport_receive(struct vport *, struct sk_buff *);
+void ovs_vport_record_error(struct vport *, enum vport_err_type err_type);
+
+/* List of statically compiled vport implementations.  Don't forget to also
+ * add yours to the list at the top of vport.c. */
+extern const struct vport_ops ovs_netdev_vport_ops;
+extern const struct vport_ops ovs_internal_vport_ops;
+
+#endif /* vport.h */