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>

Documentation/networking/00-INDEX

@@ -144,6 +144,8 @@ nfc.txt
 	- The Linux Near Field Communication (NFS) subsystem.
 olympic.txt
 	- IBM PCI Pit/Pit-Phy/Olympic Token Ring driver info.
+openvswitch.txt
+	- Open vSwitch developer documentation.
 operstates.txt
 	- Overview of network interface operational states.
 packet_mmap.txt

Documentation/networking/openvswitch.txt

+Open vSwitch datapath developer documentation
+=============================================
+
+The Open vSwitch kernel module allows flexible userspace control over
+flow-level packet processing on selected network devices.  It can be
+used to implement a plain Ethernet switch, network device bonding,
+VLAN processing, network access control, flow-based network control,
+and so on.
+
+The kernel module implements multiple "datapaths" (analogous to
+bridges), each of which can have multiple "vports" (analogous to ports
+within a bridge).  Each datapath also has associated with it a "flow
+table" that userspace populates with "flows" that map from keys based
+on packet headers and metadata to sets of actions.  The most common
+action forwards the packet to another vport; other actions are also
+implemented.
+
+When a packet arrives on a vport, the kernel module processes it by
+extracting its flow key and looking it up in the flow table.  If there
+is a matching flow, it executes the associated actions.  If there is
+no match, it queues the packet to userspace for processing (as part of
+its processing, userspace will likely set up a flow to handle further
+packets of the same type entirely in-kernel).
+
+
+Flow key compatibility
+----------------------
+
+Network protocols evolve over time.  New protocols become important
+and existing protocols lose their prominence.  For the Open vSwitch
+kernel module to remain relevant, it must be possible for newer
+versions to parse additional protocols as part of the flow key.  It
+might even be desirable, someday, to drop support for parsing
+protocols that have become obsolete.  Therefore, the Netlink interface
+to Open vSwitch is designed to allow carefully written userspace
+applications to work with any version of the flow key, past or future.
+
+To support this forward and backward compatibility, whenever the
+kernel module passes a packet to userspace, it also passes along the
+flow key that it parsed from the packet.  Userspace then extracts its
+own notion of a flow key from the packet and compares it against the
+kernel-provided version:
+
+    - If userspace's notion of the flow key for the packet matches the
+      kernel's, then nothing special is necessary.
+
+    - If the kernel's flow key includes more fields than the userspace
+      version of the flow key, for example if the kernel decoded IPv6
+      headers but userspace stopped at the Ethernet type (because it
+      does not understand IPv6), then again nothing special is
+      necessary.  Userspace can still set up a flow in the usual way,
+      as long as it uses the kernel-provided flow key to do it.
+
+    - If the userspace flow key includes more fields than the
+      kernel's, for example if userspace decoded an IPv6 header but
+      the kernel stopped at the Ethernet type, then userspace can
+      forward the packet manually, without setting up a flow in the
+      kernel.  This case is bad for performance because every packet
+      that the kernel considers part of the flow must go to userspace,
+      but the forwarding behavior is correct.  (If userspace can
+      determine that the values of the extra fields would not affect
+      forwarding behavior, then it could set up a flow anyway.)
+
+How flow keys evolve over time is important to making this work, so
+the following sections go into detail.
+
+
+Flow key format
+---------------
+
+A flow key is passed over a Netlink socket as a sequence of Netlink
+attributes.  Some attributes represent packet metadata, defined as any
+information about a packet that cannot be extracted from the packet
+itself, e.g. the vport on which the packet was received.  Most
+attributes, however, are extracted from headers within the packet,
+e.g. source and destination addresses from Ethernet, IP, or TCP
+headers.
+
+The <linux/openvswitch.h> header file defines the exact format of the
+flow key attributes.  For informal explanatory purposes here, we write
+them as comma-separated strings, with parentheses indicating arguments
+and nesting.  For example, the following could represent a flow key
+corresponding to a TCP packet that arrived on vport 1:
+
+    in_port(1), eth(src=e0:91:f5:21:d0:b2, dst=00:02:e3:0f:80:a4),
+    eth_type(0x0800), ipv4(src=172.16.0.20, dst=172.18.0.52, proto=17, tos=0,
+    frag=no), tcp(src=49163, dst=80)
+
+Often we ellipsize arguments not important to the discussion, e.g.:
+
+    in_port(1), eth(...), eth_type(0x0800), ipv4(...), tcp(...)
+
+
+Basic rule for evolving flow keys
+---------------------------------
+
+Some care is needed to really maintain forward and backward
+compatibility for applications that follow the rules listed under
+"Flow key compatibility" above.
+
+The basic rule is obvious:
+
+    ------------------------------------------------------------------
+    New network protocol support must only supplement existing flow
+    key attributes.  It must not change the meaning of already defined
+    flow key attributes.
+    ------------------------------------------------------------------
+
+This rule does have less-obvious consequences so it is worth working
+through a few examples.  Suppose, for example, that the kernel module
+did not already implement VLAN parsing.  Instead, it just interpreted
+the 802.1Q TPID (0x8100) as the Ethertype then stopped parsing the
+packet.  The flow key for any packet with an 802.1Q header would look
+essentially like this, ignoring metadata:
+
+    eth(...), eth_type(0x8100)
+
+Naively, to add VLAN support, it makes sense to add a new "vlan" flow
+key attribute to contain the VLAN tag, then continue to decode the
+encapsulated headers beyond the VLAN tag using the existing field
+definitions.  With this change, an TCP packet in VLAN 10 would have a
+flow key much like this:
+
+    eth(...), vlan(vid=10, pcp=0), eth_type(0x0800), ip(proto=6, ...), tcp(...)
+
+But this change would negatively affect a userspace application that
+has not been updated to understand the new "vlan" flow key attribute.
+The application could, following the flow compatibility rules above,
+ignore the "vlan" attribute that it does not understand and therefore
+assume that the flow contained IP packets.  This is a bad assumption
+(the flow only contains IP packets if one parses and skips over the
+802.1Q header) and it could cause the application's behavior to change
+across kernel versions even though it follows the compatibility rules.
+
+The solution is to use a set of nested attributes.  This is, for
+example, why 802.1Q support uses nested attributes.  A TCP packet in
+VLAN 10 is actually expressed as:
+
+    eth(...), eth_type(0x8100), vlan(vid=10, pcp=0), encap(eth_type(0x0800),
+    ip(proto=6, ...), tcp(...)))
+
+Notice how the "eth_type", "ip", and "tcp" flow key attributes are
+nested inside the "encap" attribute.  Thus, an application that does
+not understand the "vlan" key will not see either of those attributes
+and therefore will not misinterpret them.  (Also, the outer eth_type
+is still 0x8100, not changed to 0x0800.)
+
+Handling malformed packets
+--------------------------
+
+Don't drop packets in the kernel for malformed protocol headers, bad
+checksums, etc.  This would prevent userspace from implementing a
+simple Ethernet switch that forwards every packet.
+
+Instead, in such a case, include an attribute with "empty" content.
+It doesn't matter if the empty content could be valid protocol values,
+as long as those values are rarely seen in practice, because userspace
+can always forward all packets with those values to userspace and
+handle them individually.
+
+For example, consider a packet that contains an IP header that
+indicates protocol 6 for TCP, but which is truncated just after the IP
+header, so that the TCP header is missing.  The flow key for this
+packet would include a tcp attribute with all-zero src and dst, like
+this:
+
+    eth(...), eth_type(0x0800), ip(proto=6, ...), tcp(src=0, dst=0)
+
+As another example, consider a packet with an Ethernet type of 0x8100,
+indicating that a VLAN TCI should follow, but which is truncated just
+after the Ethernet type.  The flow key for this packet would include
+an all-zero-bits vlan and an empty encap attribute, like this:
+
+    eth(...), eth_type(0x8100), vlan(0), encap()
+
+Unlike a TCP packet with source and destination ports 0, an
+all-zero-bits VLAN TCI is not that rare, so the CFI bit (aka
+VLAN_TAG_PRESENT inside the kernel) is ordinarily set in a vlan
+attribute expressly to allow this situation to be distinguished.
+Thus, the flow key in this second example unambiguously indicates a
+missing or malformed VLAN TCI.
+
+Other rules
+-----------
+
+The other rules for flow keys are much less subtle:
+
+    - Duplicate attributes are not allowed at a given nesting level.
+
+    - Ordering of attributes is not significant.
+
+    - When the kernel sends a given flow key to userspace, it always
+      composes it the same way.  This allows userspace to hash and
+      compare entire flow keys that it may not be able to fully
+      interpret.

MAINTAINERS

@@ -4868,6 +4868,14 @@ S:	Maintained
 T:	git git://openrisc.net/~jonas/linux
 F:	arch/openrisc
 
+OPENVSWITCH
+M:	Jesse Gross <jesse@nicira.com>
+L:	dev@openvswitch.org
+W:	http://openvswitch.org
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/jesse/openvswitch.git
+S:	Maintained
+F:	net/openvswitch/
+
 OPL4 DRIVER
 M:	Clemens Ladisch <clemens@ladisch.de>
 L:	alsa-devel@alsa-project.org (moderated for non-subscribers)

net/Kconfig

@@ -215,6 +215,7 @@ source "net/sched/Kconfig"
 source "net/dcb/Kconfig"
 source "net/dns_resolver/Kconfig"
 source "net/batman-adv/Kconfig"
+source "net/openvswitch/Kconfig"
 
 config RPS
 	boolean

net/Makefile

@@ -69,3 +69,4 @@ obj-$(CONFIG_DNS_RESOLVER)	+= dns_resolver/
 obj-$(CONFIG_CEPH_LIB)		+= ceph/
 obj-$(CONFIG_BATMAN_ADV)	+= batman-adv/
 obj-$(CONFIG_NFC)		+= nfc/
+obj-$(CONFIG_OPENVSWITCH)	+= openvswitch/

net/openvswitch/Kconfig

+#
+# Open vSwitch
+#
+
+config OPENVSWITCH
+	tristate "Open vSwitch"
+	---help---
+	  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.
+
+	  To compile this code as a module, choose M here: the module will be
+	  called openvswitch.
+
+	  If unsure, say N.

net/openvswitch/Makefile

+#
+# Makefile for Open vSwitch.
+#
+
+obj-$(CONFIG_OPENVSWITCH) += openvswitch.o
+
+openvswitch-y := \
+	actions.o \
+	datapath.o \
+	dp_notify.o \
+	flow.o \
+	vport.o \
+	vport-internal_dev.o \
+	vport-netdev.o \

net/openvswitch/datapath.h

+/*
+ * 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 */

net/openvswitch/dp_notify.c

+/*
+ * 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
+ */
+
+#include <linux/netdevice.h>
+#include <net/genetlink.h>
+
+#include "datapath.h"
+#include "vport-internal_dev.h"
+#include "vport-netdev.h"
+
+static int dp_device_event(struct notifier_block *unused, unsigned long event,
+			   void *ptr)
+{
+	struct net_device *dev = ptr;
+	struct vport *vport;
+
+	if (ovs_is_internal_dev(dev))
+		vport = ovs_internal_dev_get_vport(dev);
+	else
+		vport = ovs_netdev_get_vport(dev);
+
+	if (!vport)
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case NETDEV_UNREGISTER:
+		if (!ovs_is_internal_dev(dev)) {
+			struct sk_buff *notify;
+
+			notify = ovs_vport_cmd_build_info(vport, 0, 0,
+							  OVS_VPORT_CMD_DEL);
+			ovs_dp_detach_port(vport);
+			if (IS_ERR(notify)) {
+				netlink_set_err(init_net.genl_sock, 0,
+						ovs_dp_vport_multicast_group.id,
+						PTR_ERR(notify));
+				break;
+			}
+
+			genlmsg_multicast(notify, 0, ovs_dp_vport_multicast_group.id,
+					  GFP_KERNEL);
+		}
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+struct notifier_block ovs_dp_device_notifier = {
+	.notifier_call = dp_device_event
+};

net/openvswitch/flow.h

+/*
+ * 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 FLOW_H
+#define FLOW_H 1
+
+#include <linux/kernel.h>
+#include <linux/netlink.h>
+#include <linux/openvswitch.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/rcupdate.h>
+#include <linux/if_ether.h>
+#include <linux/in6.h>
+#include <linux/jiffies.h>
+#include <linux/time.h>
+#include <linux/flex_array.h>
+#include <net/inet_ecn.h>
+
+struct sk_buff;
+
+struct sw_flow_actions {
+	struct rcu_head rcu;
+	u32 actions_len;
+	struct nlattr actions[];
+};
+
+struct sw_flow_key {
+	struct {
+		u32	priority;	/* Packet QoS priority. */
+		u16	in_port;	/* Input switch port (or USHRT_MAX). */
+	} phy;
+	struct {
+		u8     src[ETH_ALEN];	/* Ethernet source address. */
+		u8     dst[ETH_ALEN];	/* Ethernet destination address. */
+		__be16 tci;		/* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
+		__be16 type;		/* Ethernet frame type. */
+	} eth;
+	struct {
+		u8     proto;		/* IP protocol or lower 8 bits of ARP opcode. */
+		u8     tos;		/* IP ToS. */
+		u8     ttl;		/* IP TTL/hop limit. */
+		u8     frag;		/* One of OVS_FRAG_TYPE_*. */
+	} ip;
+	union {
+		struct {
+			struct {
+				__be32 src;	/* IP source address. */
+				__be32 dst;	/* IP destination address. */
+			} addr;
+			union {
+				struct {
+					__be16 src;		/* TCP/UDP source port. */
+					__be16 dst;		/* TCP/UDP destination port. */
+				} tp;
+				struct {
+					u8 sha[ETH_ALEN];	/* ARP source hardware address. */
+					u8 tha[ETH_ALEN];	/* ARP target hardware address. */
+				} arp;
+			};
+		} ipv4;
+		struct {
+			struct {
+				struct in6_addr src;	/* IPv6 source address. */
+				struct in6_addr dst;	/* IPv6 destination address. */
+			} addr;
+			__be32 label;			/* IPv6 flow label. */
+			struct {
+				__be16 src;		/* TCP/UDP source port. */
+				__be16 dst;		/* TCP/UDP destination port. */
+			} tp;
+			struct {
+				struct in6_addr target;	/* ND target address. */
+				u8 sll[ETH_ALEN];	/* ND source link layer address. */
+				u8 tll[ETH_ALEN];	/* ND target link layer address. */
+			} nd;
+		} ipv6;
+	};
+};
+
+struct sw_flow {
+	struct rcu_head rcu;
+	struct hlist_node hash_node[2];
+	u32 hash;
+
+	struct sw_flow_key key;
+	struct sw_flow_actions __rcu *sf_acts;
+
+	spinlock_t lock;	/* Lock for values below. */
+	unsigned long used;	/* Last used time (in jiffies). */
+	u64 packet_count;	/* Number of packets matched. */
+	u64 byte_count;		/* Number of bytes matched. */
+	u8 tcp_flags;		/* Union of seen TCP flags. */
+};
+
+struct arp_eth_header {
+	__be16      ar_hrd;	/* format of hardware address   */
+	__be16      ar_pro;	/* format of protocol address   */
+	unsigned char   ar_hln;	/* length of hardware address   */
+	unsigned char   ar_pln;	/* length of protocol address   */
+	__be16      ar_op;	/* ARP opcode (command)     */
+
+	/* Ethernet+IPv4 specific members. */
+	unsigned char       ar_sha[ETH_ALEN];	/* sender hardware address  */
+	unsigned char       ar_sip[4];		/* sender IP address        */
+	unsigned char       ar_tha[ETH_ALEN];	/* target hardware address  */
+	unsigned char       ar_tip[4];		/* target IP address        */
+} __packed;
+
+int ovs_flow_init(void);
+void ovs_flow_exit(void);
+
+struct sw_flow *ovs_flow_alloc(void);
+void ovs_flow_deferred_free(struct sw_flow *);
+void ovs_flow_free(struct sw_flow *flow);
+
+struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *);
+void ovs_flow_deferred_free_acts(struct sw_flow_actions *);
+
+int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *,
+		     int *key_lenp);
+void ovs_flow_used(struct sw_flow *, struct sk_buff *);
+u64 ovs_flow_used_time(unsigned long flow_jiffies);
+
+/* Upper bound on the length of a nlattr-formatted flow key.  The longest
+ * nlattr-formatted flow key would be:
+ *
+ *                         struct  pad  nl hdr  total
+ *                         ------  ---  ------  -----
+ *  OVS_KEY_ATTR_PRIORITY      4    --     4      8
+ *  OVS_KEY_ATTR_IN_PORT       4    --     4      8
+ *  OVS_KEY_ATTR_ETHERNET     12    --     4     16
+ *  OVS_KEY_ATTR_8021Q         4    --     4      8
+ *  OVS_KEY_ATTR_ETHERTYPE     2     2     4      8
+ *  OVS_KEY_ATTR_IPV6         40    --     4     44
+ *  OVS_KEY_ATTR_ICMPV6        2     2     4      8
+ *  OVS_KEY_ATTR_ND           28    --     4     32
+ *  -------------------------------------------------
+ *  total                                       132
+ */
+#define FLOW_BUFSIZE 132
+
+int ovs_flow_to_nlattrs(const struct sw_flow_key *, struct sk_buff *);
+int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
+		      const struct nlattr *);
+int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port,
+			       const struct nlattr *);
+
+#define TBL_MIN_BUCKETS		1024
+
+struct flow_table {
+	struct flex_array *buckets;
+	unsigned int count, n_buckets;
+	struct rcu_head rcu;
+	int node_ver;
+	u32 hash_seed;
+	bool keep_flows;
+};
+
+static inline int ovs_flow_tbl_count(struct flow_table *table)
+{
+	return table->count;
+}
+
+static inline int ovs_flow_tbl_need_to_expand(struct flow_table *table)
+{
+	return (table->count > table->n_buckets);
+}
+
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
+				    struct sw_flow_key *key, int len);
+void ovs_flow_tbl_destroy(struct flow_table *table);
+void ovs_flow_tbl_deferred_destroy(struct flow_table *table);
+struct flow_table *ovs_flow_tbl_alloc(int new_size);
+struct flow_table *ovs_flow_tbl_expand(struct flow_table *table);
+struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table);
+void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow);
+void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow);
+u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len);
+
+struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *idx);
+extern const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1];
+
+#endif /* flow.h */

net/openvswitch/vport-internal_dev.h

+/*
+ * 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_INTERNAL_DEV_H
+#define VPORT_INTERNAL_DEV_H 1
+
+#include "datapath.h"
+#include "vport.h"
+
+int ovs_is_internal_dev(const struct net_device *);
+struct vport *ovs_internal_dev_get_vport(struct net_device *);
+
+#endif /* vport-internal_dev.h */

net/openvswitch/vport-netdev.h

+/*
+ * 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_NETDEV_H
+#define VPORT_NETDEV_H 1
+
+#include <linux/netdevice.h>
+
+#include "vport.h"
+
+struct vport *ovs_netdev_get_vport(struct net_device *dev);
+
+struct netdev_vport {
+	struct net_device *dev;
+};
+
+static inline struct netdev_vport *
+netdev_vport_priv(const struct vport *vport)
+{
+	return vport_priv(vport);
+}
+
+const char *ovs_netdev_get_name(const struct vport *);
+const char *ovs_netdev_get_config(const struct vport *);
+int ovs_netdev_get_ifindex(const struct vport *);
+
+#endif /* vport_netdev.h */