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, 1912 insertions, 0 deletions

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
new file mode 100644
index 000000000000..9a2725114e99
--- /dev/null
+++ b/net/openvswitch/datapath.c
@@ -0,0 +1,1912 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/if_arp.h>
+#include <linux/if_vlan.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/jhash.h>
+#include <linux/delay.h>
+#include <linux/time.h>
+#include <linux/etherdevice.h>
+#include <linux/genetlink.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/percpu.h>
+#include <linux/rcupdate.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/version.h>
+#include <linux/ethtool.h>
+#include <linux/wait.h>
+#include <asm/system.h>
+#include <asm/div64.h>
+#include <linux/highmem.h>
+#include <linux/netfilter_bridge.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/inetdevice.h>
+#include <linux/list.h>
+#include <linux/openvswitch.h>
+#include <linux/rculist.h>
+#include <linux/dmi.h>
+#include <linux/workqueue.h>
+#include <net/genetlink.h>
+
+#include "datapath.h"
+#include "flow.h"
+#include "vport-internal_dev.h"
+
+/**
+ * DOC: Locking:
+ *
+ * Writes to device state (add/remove datapath, port, set operations on vports,
+ * etc.) are protected by RTNL.
+ *
+ * Writes to other state (flow table modifications, set miscellaneous datapath
+ * parameters, etc.) are protected by genl_mutex.  The RTNL lock nests inside
+ * genl_mutex.
+ *
+ * Reads are protected by RCU.
+ *
+ * There are a few special cases (mostly stats) that have their own
+ * synchronization but they nest under all of above and don't interact with
+ * each other.
+ */
+
+/* Global list of datapaths to enable dumping them all out.
+ * Protected by genl_mutex.
+ */
+static LIST_HEAD(dps);
+
+#define REHASH_FLOW_INTERVAL (10 * 60 * HZ)
+static void rehash_flow_table(struct work_struct *work);
+static DECLARE_DELAYED_WORK(rehash_flow_wq, rehash_flow_table);
+
+static struct vport *new_vport(const struct vport_parms *);
+static int queue_gso_packets(int dp_ifindex, struct sk_buff *,
+			     const struct dp_upcall_info *);
+static int queue_userspace_packet(int dp_ifindex, struct sk_buff *,
+				  const struct dp_upcall_info *);
+
+/* Must be called with rcu_read_lock, genl_mutex, or RTNL lock. */
+static struct datapath *get_dp(int dp_ifindex)
+{
+	struct datapath *dp = NULL;
+	struct net_device *dev;
+
+	rcu_read_lock();
+	dev = dev_get_by_index_rcu(&init_net, dp_ifindex);
+	if (dev) {
+		struct vport *vport = ovs_internal_dev_get_vport(dev);
+		if (vport)
+			dp = vport->dp;
+	}
+	rcu_read_unlock();
+
+	return dp;
+}
+
+/* Must be called with rcu_read_lock or RTNL lock. */
+const char *ovs_dp_name(const struct datapath *dp)
+{
+	struct vport *vport = rcu_dereference_rtnl(dp->ports[OVSP_LOCAL]);
+	return vport->ops->get_name(vport);
+}
+
+static int get_dpifindex(struct datapath *dp)
+{
+	struct vport *local;
+	int ifindex;
+
+	rcu_read_lock();
+
+	local = rcu_dereference(dp->ports[OVSP_LOCAL]);
+	if (local)
+		ifindex = local->ops->get_ifindex(local);
+	else
+		ifindex = 0;
+
+	rcu_read_unlock();
+
+	return ifindex;
+}
+
+static void destroy_dp_rcu(struct rcu_head *rcu)
+{
+	struct datapath *dp = container_of(rcu, struct datapath, rcu);
+
+	ovs_flow_tbl_destroy((__force struct flow_table *)dp->table);
+	free_percpu(dp->stats_percpu);
+	kfree(dp);
+}
+
+/* Called with RTNL lock and genl_lock. */
+static struct vport *new_vport(const struct vport_parms *parms)
+{
+	struct vport *vport;
+
+	vport = ovs_vport_add(parms);
+	if (!IS_ERR(vport)) {
+		struct datapath *dp = parms->dp;
+
+		rcu_assign_pointer(dp->ports[parms->port_no], vport);
+		list_add(&vport->node, &dp->port_list);
+	}
+
+	return vport;
+}
+
+/* Called with RTNL lock. */
+void ovs_dp_detach_port(struct vport *p)
+{
+	ASSERT_RTNL();
+
+	/* First drop references to device. */
+	list_del(&p->node);
+	rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
+
+	/* Then destroy it. */
+	ovs_vport_del(p);
+}
+
+/* Must be called with rcu_read_lock. */
+void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
+{
+	struct datapath *dp = p->dp;
+	struct sw_flow *flow;
+	struct dp_stats_percpu *stats;
+	struct sw_flow_key key;
+	u64 *stats_counter;
+	int error;
+	int key_len;
+
+	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
+
+	/* Extract flow from 'skb' into 'key'. */
+	error = ovs_flow_extract(skb, p->port_no, &key, &key_len);
+	if (unlikely(error)) {
+		kfree_skb(skb);
+		return;
+	}
+
+	/* Look up flow. */
+	flow = ovs_flow_tbl_lookup(rcu_dereference(dp->table), &key, key_len);
+	if (unlikely(!flow)) {
+		struct dp_upcall_info upcall;
+
+		upcall.cmd = OVS_PACKET_CMD_MISS;
+		upcall.key = &key;
+		upcall.userdata = NULL;
+		upcall.pid = p->upcall_pid;
+		ovs_dp_upcall(dp, skb, &upcall);
+		consume_skb(skb);
+		stats_counter = &stats->n_missed;
+		goto out;
+	}
+
+	OVS_CB(skb)->flow = flow;
+
+	stats_counter = &stats->n_hit;
+	ovs_flow_used(OVS_CB(skb)->flow, skb);
+	ovs_execute_actions(dp, skb);
+
+out:
+	/* Update datapath statistics. */
+	u64_stats_update_begin(&stats->sync);
+	(*stats_counter)++;
+	u64_stats_update_end(&stats->sync);
+}
+
+static struct genl_family dp_packet_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = sizeof(struct ovs_header),
+	.name = OVS_PACKET_FAMILY,
+	.version = OVS_PACKET_VERSION,
+	.maxattr = OVS_PACKET_ATTR_MAX
+};
+
+int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
+	      const struct dp_upcall_info *upcall_info)
+{
+	struct dp_stats_percpu *stats;
+	int dp_ifindex;
+	int err;
+
+	if (upcall_info->pid == 0) {
+		err = -ENOTCONN;
+		goto err;
+	}
+
+	dp_ifindex = get_dpifindex(dp);
+	if (!dp_ifindex) {
+		err = -ENODEV;
+		goto err;
+	}
+
+	if (!skb_is_gso(skb))
+		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
+	else
+		err = queue_gso_packets(dp_ifindex, skb, upcall_info);
+	if (err)
+		goto err;
+
+	return 0;
+
+err:
+	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
+
+	u64_stats_update_begin(&stats->sync);
+	stats->n_lost++;
+	u64_stats_update_end(&stats->sync);
+
+	return err;
+}
+
+static int queue_gso_packets(int dp_ifindex, struct sk_buff *skb,
+			     const struct dp_upcall_info *upcall_info)
+{
+	struct dp_upcall_info later_info;
+	struct sw_flow_key later_key;
+	struct sk_buff *segs, *nskb;
+	int err;
+
+	segs = skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM);
+	if (IS_ERR(skb))
+		return PTR_ERR(skb);
+
+	/* Queue all of the segments. */
+	skb = segs;
+	do {
+		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
+		if (err)
+			break;
+
+		if (skb == segs && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) {
+			/* The initial flow key extracted by ovs_flow_extract()
+			 * in this case is for a first fragment, so we need to
+			 * properly mark later fragments.
+			 */
+			later_key = *upcall_info->key;
+			later_key.ip.frag = OVS_FRAG_TYPE_LATER;
+
+			later_info = *upcall_info;
+			later_info.key = &later_key;
+			upcall_info = &later_info;
+		}
+	} while ((skb = skb->next));
+
+	/* Free all of the segments. */
+	skb = segs;
+	do {
+		nskb = skb->next;
+		if (err)
+			kfree_skb(skb);
+		else
+			consume_skb(skb);
+	} while ((skb = nskb));
+	return err;
+}
+
+static int queue_userspace_packet(int dp_ifindex, struct sk_buff *skb,
+				  const struct dp_upcall_info *upcall_info)
+{
+	struct ovs_header *upcall;
+	struct sk_buff *nskb = NULL;
+	struct sk_buff *user_skb; /* to be queued to userspace */
+	struct nlattr *nla;
+	unsigned int len;
+	int err;
+
+	if (vlan_tx_tag_present(skb)) {
+		nskb = skb_clone(skb, GFP_ATOMIC);
+		if (!nskb)
+			return -ENOMEM;
+
+		nskb = __vlan_put_tag(nskb, vlan_tx_tag_get(nskb));
+		if (!skb)
+			return -ENOMEM;
+
+		nskb->vlan_tci = 0;
+		skb = nskb;
+	}
+
+	if (nla_attr_size(skb->len) > USHRT_MAX) {
+		err = -EFBIG;
+		goto out;
+	}
+
+	len = sizeof(struct ovs_header);
+	len += nla_total_size(skb->len);
+	len += nla_total_size(FLOW_BUFSIZE);
+	if (upcall_info->cmd == OVS_PACKET_CMD_ACTION)
+		len += nla_total_size(8);
+
+	user_skb = genlmsg_new(len, GFP_ATOMIC);
+	if (!user_skb) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
+			     0, upcall_info->cmd);
+	upcall->dp_ifindex = dp_ifindex;
+
+	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
+	ovs_flow_to_nlattrs(upcall_info->key, user_skb);
+	nla_nest_end(user_skb, nla);
+
+	if (upcall_info->userdata)
+		nla_put_u64(user_skb, OVS_PACKET_ATTR_USERDATA,
+			    nla_get_u64(upcall_info->userdata));
+
+	nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
+
+	skb_copy_and_csum_dev(skb, nla_data(nla));
+
+	err = genlmsg_unicast(&init_net, user_skb, upcall_info->pid);
+
+out:
+	kfree_skb(nskb);
+	return err;
+}
+
+/* Called with genl_mutex. */
+static int flush_flows(int dp_ifindex)
+{
+	struct flow_table *old_table;
+	struct flow_table *new_table;
+	struct datapath *dp;
+
+	dp = get_dp(dp_ifindex);
+	if (!dp)
+		return -ENODEV;
+
+	old_table = genl_dereference(dp->table);
+	new_table = ovs_flow_tbl_alloc(TBL_MIN_BUCKETS);
+	if (!new_table)
+		return -ENOMEM;
+
+	rcu_assign_pointer(dp->table, new_table);
+
+	ovs_flow_tbl_deferred_destroy(old_table);
+	return 0;
+}
+
+static int validate_actions(const struct nlattr *attr,
+				const struct sw_flow_key *key, int depth);
+
+static int validate_sample(const struct nlattr *attr,
+				const struct sw_flow_key *key, int depth)
+{
+	const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1];
+	const struct nlattr *probability, *actions;
+	const struct nlattr *a;
+	int rem;
+
+	memset(attrs, 0, sizeof(attrs));
+	nla_for_each_nested(a, attr, rem) {
+		int type = nla_type(a);
+		if (!type || type > OVS_SAMPLE_ATTR_MAX || attrs[type])
+			return -EINVAL;
+		attrs[type] = a;
+	}
+	if (rem)
+		return -EINVAL;
+
+	probability = attrs[OVS_SAMPLE_ATTR_PROBABILITY];
+	if (!probability || nla_len(probability) != sizeof(u32))
+		return -EINVAL;
+
+	actions = attrs[OVS_SAMPLE_ATTR_ACTIONS];
+	if (!actions || (nla_len(actions) && nla_len(actions) < NLA_HDRLEN))
+		return -EINVAL;
+	return validate_actions(actions, key, depth + 1);
+}
+
+static int validate_set(const struct nlattr *a,
+			const struct sw_flow_key *flow_key)
+{
+	const struct nlattr *ovs_key = nla_data(a);
+	int key_type = nla_type(ovs_key);
+
+	/* There can be only one key in a action */
+	if (nla_total_size(nla_len(ovs_key)) != nla_len(a))
+		return -EINVAL;
+
+	if (key_type > OVS_KEY_ATTR_MAX ||
+	    nla_len(ovs_key) != ovs_key_lens[key_type])
+		return -EINVAL;
+
+	switch (key_type) {
+	const struct ovs_key_ipv4 *ipv4_key;
+
+	case OVS_KEY_ATTR_PRIORITY:
+	case OVS_KEY_ATTR_ETHERNET:
+		break;
+
+	case OVS_KEY_ATTR_IPV4:
+		if (flow_key->eth.type != htons(ETH_P_IP))
+			return -EINVAL;
+
+		if (!flow_key->ipv4.addr.src || !flow_key->ipv4.addr.dst)
+			return -EINVAL;
+
+		ipv4_key = nla_data(ovs_key);
+		if (ipv4_key->ipv4_proto != flow_key->ip.proto)
+			return -EINVAL;
+
+		if (ipv4_key->ipv4_frag != flow_key->ip.frag)
+			return -EINVAL;
+
+		break;
+
+	case OVS_KEY_ATTR_TCP:
+		if (flow_key->ip.proto != IPPROTO_TCP)
+			return -EINVAL;
+
+		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
+			return -EINVAL;
+
+		break;
+
+	case OVS_KEY_ATTR_UDP:
+		if (flow_key->ip.proto != IPPROTO_UDP)
+			return -EINVAL;
+
+		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
+			return -EINVAL;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int validate_userspace(const struct nlattr *attr)
+{
+	static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] =	{
+		[OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 },
+		[OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_U64 },
+	};
+	struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1];
+	int error;
+
+	error = nla_parse_nested(a, OVS_USERSPACE_ATTR_MAX,
+				 attr, userspace_policy);
+	if (error)
+		return error;
+
+	if (!a[OVS_USERSPACE_ATTR_PID] ||
+	    !nla_get_u32(a[OVS_USERSPACE_ATTR_PID]))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int validate_actions(const struct nlattr *attr,
+				const struct sw_flow_key *key,  int depth)
+{
+	const struct nlattr *a;
+	int rem, err;
+
+	if (depth >= SAMPLE_ACTION_DEPTH)
+		return -EOVERFLOW;
+
+	nla_for_each_nested(a, attr, rem) {
+		/* Expected argument lengths, (u32)-1 for variable length. */
+		static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
+			[OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
+			[OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
+			[OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
+			[OVS_ACTION_ATTR_POP_VLAN] = 0,
+			[OVS_ACTION_ATTR_SET] = (u32)-1,
+			[OVS_ACTION_ATTR_SAMPLE] = (u32)-1
+		};
+		const struct ovs_action_push_vlan *vlan;
+		int type = nla_type(a);
+
+		if (type > OVS_ACTION_ATTR_MAX ||
+		    (action_lens[type] != nla_len(a) &&
+		     action_lens[type] != (u32)-1))
+			return -EINVAL;
+
+		switch (type) {
+		case OVS_ACTION_ATTR_UNSPEC:
+			return -EINVAL;
+
+		case OVS_ACTION_ATTR_USERSPACE:
+			err = validate_userspace(a);
+			if (err)
+				return err;
+			break;
+
+		case OVS_ACTION_ATTR_OUTPUT:
+			if (nla_get_u32(a) >= DP_MAX_PORTS)
+				return -EINVAL;
+			break;
+
+
+		case OVS_ACTION_ATTR_POP_VLAN:
+			break;
+
+		case OVS_ACTION_ATTR_PUSH_VLAN:
+			vlan = nla_data(a);
+			if (vlan->vlan_tpid != htons(ETH_P_8021Q))
+				return -EINVAL;
+			if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT)))
+				return -EINVAL;
+			break;
+
+		case OVS_ACTION_ATTR_SET:
+			err = validate_set(a, key);
+			if (err)
+				return err;
+			break;
+
+		case OVS_ACTION_ATTR_SAMPLE:
+			err = validate_sample(a, key, depth);
+			if (err)
+				return err;
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	if (rem > 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void clear_stats(struct sw_flow *flow)
+{
+	flow->used = 0;
+	flow->tcp_flags = 0;
+	flow->packet_count = 0;
+	flow->byte_count = 0;
+}
+
+static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
+{
+	struct ovs_header *ovs_header = info->userhdr;
+	struct nlattr **a = info->attrs;
+	struct sw_flow_actions *acts;
+	struct sk_buff *packet;
+	struct sw_flow *flow;
+	struct datapath *dp;
+	struct ethhdr *eth;
+	int len;
+	int err;
+	int key_len;
+
+	err = -EINVAL;
+	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
+	    !a[OVS_PACKET_ATTR_ACTIONS] ||
+	    nla_len(a[OVS_PACKET_ATTR_PACKET]) < ETH_HLEN)
+		goto err;
+
+	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
+	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
+	err = -ENOMEM;
+	if (!packet)
+		goto err;
+	skb_reserve(packet, NET_IP_ALIGN);
+
+	memcpy(__skb_put(packet, len), nla_data(a[OVS_PACKET_ATTR_PACKET]), len);
+
+	skb_reset_mac_header(packet);
+	eth = eth_hdr(packet);
+
+	/* Normally, setting the skb 'protocol' field would be handled by a
+	 * call to eth_type_trans(), but it assumes there's a sending
+	 * device, which we may not have. */
+	if (ntohs(eth->h_proto) >= 1536)
+		packet->protocol = eth->h_proto;
+	else
+		packet->protocol = htons(ETH_P_802_2);
+
+	/* Build an sw_flow for sending this packet. */
+	flow = ovs_flow_alloc();
+	err = PTR_ERR(flow);
+	if (IS_ERR(flow))
+		goto err_kfree_skb;
+
+	err = ovs_flow_extract(packet, -1, &flow->key, &key_len);
+	if (err)
+		goto err_flow_free;
+
+	err = ovs_flow_metadata_from_nlattrs(&flow->key.phy.priority,
+					     &flow->key.phy.in_port,
+					     a[OVS_PACKET_ATTR_KEY]);
+	if (err)
+		goto err_flow_free;
+
+	err = validate_actions(a[OVS_PACKET_ATTR_ACTIONS], &flow->key, 0);
+	if (err)
+		goto err_flow_free;
+
+	flow->hash = ovs_flow_hash(&flow->key, key_len);
+
+	acts = ovs_flow_actions_alloc(a[OVS_PACKET_ATTR_ACTIONS]);
+	err = PTR_ERR(acts);
+	if (IS_ERR(acts))
+		goto err_flow_free;
+	rcu_assign_pointer(flow->sf_acts, acts);
+
+	OVS_CB(packet)->flow = flow;
+	packet->priority = flow->key.phy.priority;
+
+	rcu_read_lock();
+	dp = get_dp(ovs_header->dp_ifindex);
+	err = -ENODEV;
+	if (!dp)
+		goto err_unlock;
+
+	local_bh_disable();
+	err = ovs_execute_actions(dp, packet);
+	local_bh_enable();
+	rcu_read_unlock();
+
+	ovs_flow_free(flow);
+	return err;
+
+err_unlock:
+	rcu_read_unlock();
+err_flow_free:
+	ovs_flow_free(flow);
+err_kfree_skb:
+	kfree_skb(packet);
+err:
+	return err;
+}
+
+static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
+	[OVS_PACKET_ATTR_PACKET] = { .type = NLA_UNSPEC },
+	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
+	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
+};
+
+static struct genl_ops dp_packet_genl_ops[] = {
+	{ .cmd = OVS_PACKET_CMD_EXECUTE,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = packet_policy,
+	  .doit = ovs_packet_cmd_execute
+	}
+};
+
+static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats)
+{
+	int i;
+	struct flow_table *table = genl_dereference(dp->table);
+
+	stats->n_flows = ovs_flow_tbl_count(table);
+
+	stats->n_hit = stats->n_missed = stats->n_lost = 0;
+	for_each_possible_cpu(i) {
+		const struct dp_stats_percpu *percpu_stats;
+		struct dp_stats_percpu local_stats;
+		unsigned int start;
+
+		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
+
+		do {
+			start = u64_stats_fetch_begin_bh(&percpu_stats->sync);
+			local_stats = *percpu_stats;
+		} while (u64_stats_fetch_retry_bh(&percpu_stats->sync, start));
+
+		stats->n_hit += local_stats.n_hit;
+		stats->n_missed += local_stats.n_missed;
+		stats->n_lost += local_stats.n_lost;
+	}
+}
+
+static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
+	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
+	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
+	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
+};
+
+static struct genl_family dp_flow_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = sizeof(struct ovs_header),
+	.name = OVS_FLOW_FAMILY,
+	.version = OVS_FLOW_VERSION,
+	.maxattr = OVS_FLOW_ATTR_MAX
+};
+
+static struct genl_multicast_group ovs_dp_flow_multicast_group = {
+	.name = OVS_FLOW_MCGROUP
+};
+
+/* Called with genl_lock. */
+static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
+				  struct sk_buff *skb, u32 pid,
+				  u32 seq, u32 flags, u8 cmd)
+{
+	const int skb_orig_len = skb->len;
+	const struct sw_flow_actions *sf_acts;
+	struct ovs_flow_stats stats;
+	struct ovs_header *ovs_header;
+	struct nlattr *nla;
+	unsigned long used;
+	u8 tcp_flags;
+	int err;
+
+	sf_acts = rcu_dereference_protected(flow->sf_acts,
+					    lockdep_genl_is_held());
+
+	ovs_header = genlmsg_put(skb, pid, seq, &dp_flow_genl_family, flags, cmd);
+	if (!ovs_header)
+		return -EMSGSIZE;
+
+	ovs_header->dp_ifindex = get_dpifindex(dp);
+
+	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
+	if (!nla)
+		goto nla_put_failure;
+	err = ovs_flow_to_nlattrs(&flow->key, skb);
+	if (err)
+		goto error;
+	nla_nest_end(skb, nla);
+
+	spin_lock_bh(&flow->lock);
+	used = flow->used;
+	stats.n_packets = flow->packet_count;
+	stats.n_bytes = flow->byte_count;
+	tcp_flags = flow->tcp_flags;
+	spin_unlock_bh(&flow->lock);
+
+	if (used)
+		NLA_PUT_U64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used));
+
+	if (stats.n_packets)
+		NLA_PUT(skb, OVS_FLOW_ATTR_STATS,
+			sizeof(struct ovs_flow_stats), &stats);
+
+	if (tcp_flags)
+		NLA_PUT_U8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags);
+
+	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
+	 * this is the first flow to be dumped into 'skb'.  This is unusual for
+	 * Netlink but individual action lists can be longer than
+	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
+	 * The userspace caller can always fetch the actions separately if it
+	 * really wants them.  (Most userspace callers in fact don't care.)
+	 *
+	 * This can only fail for dump operations because the skb is always
+	 * properly sized for single flows.
+	 */
+	err = nla_put(skb, OVS_FLOW_ATTR_ACTIONS, sf_acts->actions_len,
+		      sf_acts->actions);
+	if (err < 0 && skb_orig_len)
+		goto error;
+
+	return genlmsg_end(skb, ovs_header);
+
+nla_put_failure:
+	err = -EMSGSIZE;
+error:
+	genlmsg_cancel(skb, ovs_header);
+	return err;
+}
+
+static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow)
+{
+	const struct sw_flow_actions *sf_acts;
+	int len;
+
+	sf_acts = rcu_dereference_protected(flow->sf_acts,
+					    lockdep_genl_is_held());
+
+	/* OVS_FLOW_ATTR_KEY */
+	len = nla_total_size(FLOW_BUFSIZE);
+	/* OVS_FLOW_ATTR_ACTIONS */
+	len += nla_total_size(sf_acts->actions_len);
+	/* OVS_FLOW_ATTR_STATS */
+	len += nla_total_size(sizeof(struct ovs_flow_stats));
+	/* OVS_FLOW_ATTR_TCP_FLAGS */
+	len += nla_total_size(1);
+	/* OVS_FLOW_ATTR_USED */
+	len += nla_total_size(8);
+
+	len += NLMSG_ALIGN(sizeof(struct ovs_header));
+
+	return genlmsg_new(len, GFP_KERNEL);
+}
+
+static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
+					       struct datapath *dp,
+					       u32 pid, u32 seq, u8 cmd)
+{
+	struct sk_buff *skb;
+	int retval;
+
+	skb = ovs_flow_cmd_alloc_info(flow);
+	if (!skb)
+		return ERR_PTR(-ENOMEM);
+
+	retval = ovs_flow_cmd_fill_info(flow, dp, skb, pid, seq, 0, cmd);
+	BUG_ON(retval < 0);
+	return skb;
+}
+
+static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct ovs_header *ovs_header = info->userhdr;
+	struct sw_flow_key key;
+	struct sw_flow *flow;
+	struct sk_buff *reply;
+	struct datapath *dp;
+	struct flow_table *table;
+	int error;
+	int key_len;
+
+	/* Extract key. */
+	error = -EINVAL;
+	if (!a[OVS_FLOW_ATTR_KEY])
+		goto error;
+	error = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
+	if (error)
+		goto error;
+
+	/* Validate actions. */
+	if (a[OVS_FLOW_ATTR_ACTIONS]) {
+		error = validate_actions(a[OVS_FLOW_ATTR_ACTIONS], &key,  0);
+		if (error)
+			goto error;
+	} else if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW) {
+		error = -EINVAL;
+		goto error;
+	}
+
+	dp = get_dp(ovs_header->dp_ifindex);
+	error = -ENODEV;
+	if (!dp)
+		goto error;
+
+	table = genl_dereference(dp->table);
+	flow = ovs_flow_tbl_lookup(table, &key, key_len);
+	if (!flow) {
+		struct sw_flow_actions *acts;
+
+		/* Bail out if we're not allowed to create a new flow. */
+		error = -ENOENT;
+		if (info->genlhdr->cmd == OVS_FLOW_CMD_SET)
+			goto error;
+
+		/* Expand table, if necessary, to make room. */
+		if (ovs_flow_tbl_need_to_expand(table)) {
+			struct flow_table *new_table;
+
+			new_table = ovs_flow_tbl_expand(table);
+			if (!IS_ERR(new_table)) {
+				rcu_assign_pointer(dp->table, new_table);
+				ovs_flow_tbl_deferred_destroy(table);
+				table = genl_dereference(dp->table);
+			}
+		}
+
+		/* Allocate flow. */
+		flow = ovs_flow_alloc();
+		if (IS_ERR(flow)) {
+			error = PTR_ERR(flow);
+			goto error;
+		}
+		flow->key = key;
+		clear_stats(flow);
+
+		/* Obtain actions. */
+		acts = ovs_flow_actions_alloc(a[OVS_FLOW_ATTR_ACTIONS]);
+		error = PTR_ERR(acts);
+		if (IS_ERR(acts))
+			goto error_free_flow;
+		rcu_assign_pointer(flow->sf_acts, acts);
+
+		/* Put flow in bucket. */
+		flow->hash = ovs_flow_hash(&key, key_len);
+		ovs_flow_tbl_insert(table, flow);
+
+		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
+						info->snd_seq,
+						OVS_FLOW_CMD_NEW);
+	} else {
+		/* We found a matching flow. */
+		struct sw_flow_actions *old_acts;
+		struct nlattr *acts_attrs;
+
+		/* Bail out if we're not allowed to modify an existing flow.
+		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
+		 * because Generic Netlink treats the latter as a dump
+		 * request.  We also accept NLM_F_EXCL in case that bug ever
+		 * gets fixed.
+		 */
+		error = -EEXIST;
+		if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW &&
+		    info->nlhdr->nlmsg_flags & (NLM_F_CREATE | NLM_F_EXCL))
+			goto error;
+
+		/* Update actions. */
+		old_acts = rcu_dereference_protected(flow->sf_acts,
+						     lockdep_genl_is_held());
+		acts_attrs = a[OVS_FLOW_ATTR_ACTIONS];
+		if (acts_attrs &&
+		   (old_acts->actions_len != nla_len(acts_attrs) ||
+		   memcmp(old_acts->actions, nla_data(acts_attrs),
+			  old_acts->actions_len))) {
+			struct sw_flow_actions *new_acts;
+
+			new_acts = ovs_flow_actions_alloc(acts_attrs);
+			error = PTR_ERR(new_acts);
+			if (IS_ERR(new_acts))
+				goto error;
+
+			rcu_assign_pointer(flow->sf_acts, new_acts);
+			ovs_flow_deferred_free_acts(old_acts);
+		}
+
+		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
+					       info->snd_seq, OVS_FLOW_CMD_NEW);
+
+		/* Clear stats. */
+		if (a[OVS_FLOW_ATTR_CLEAR]) {
+			spin_lock_bh(&flow->lock);
+			clear_stats(flow);
+			spin_unlock_bh(&flow->lock);
+		}
+	}
+
+	if (!IS_ERR(reply))
+		genl_notify(reply, genl_info_net(info), info->snd_pid,
+			   ovs_dp_flow_multicast_group.id, info->nlhdr,
+			   GFP_KERNEL);
+	else
+		netlink_set_err(init_net.genl_sock, 0,
+				ovs_dp_flow_multicast_group.id, PTR_ERR(reply));
+	return 0;
+
+error_free_flow:
+	ovs_flow_free(flow);
+error:
+	return error;
+}
+
+static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct ovs_header *ovs_header = info->userhdr;
+	struct sw_flow_key key;
+	struct sk_buff *reply;
+	struct sw_flow *flow;
+	struct datapath *dp;
+	struct flow_table *table;
+	int err;
+	int key_len;
+
+	if (!a[OVS_FLOW_ATTR_KEY])
+		return -EINVAL;
+	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
+	if (err)
+		return err;
+
+	dp = get_dp(ovs_header->dp_ifindex);
+	if (!dp)
+		return -ENODEV;
+
+	table = genl_dereference(dp->table);
+	flow = ovs_flow_tbl_lookup(table, &key, key_len);
+	if (!flow)
+		return -ENOENT;
+
+	reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
+					info->snd_seq, OVS_FLOW_CMD_NEW);
+	if (IS_ERR(reply))
+		return PTR_ERR(reply);
+
+	return genlmsg_reply(reply, info);
+}
+
+static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct ovs_header *ovs_header = info->userhdr;
+	struct sw_flow_key key;
+	struct sk_buff *reply;
+	struct sw_flow *flow;
+	struct datapath *dp;
+	struct flow_table *table;
+	int err;
+	int key_len;
+
+	if (!a[OVS_FLOW_ATTR_KEY])
+		return flush_flows(ovs_header->dp_ifindex);
+	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
+	if (err)
+		return err;
+
+	dp = get_dp(ovs_header->dp_ifindex);
+	if (!dp)
+		return -ENODEV;
+
+	table = genl_dereference(dp->table);
+	flow = ovs_flow_tbl_lookup(table, &key, key_len);
+	if (!flow)
+		return -ENOENT;
+
+	reply = ovs_flow_cmd_alloc_info(flow);
+	if (!reply)
+		return -ENOMEM;
+
+	ovs_flow_tbl_remove(table, flow);
+
+	err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_pid,
+				     info->snd_seq, 0, OVS_FLOW_CMD_DEL);
+	BUG_ON(err < 0);
+
+	ovs_flow_deferred_free(flow);
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_flow_multicast_group.id, info->nlhdr, GFP_KERNEL);
+	return 0;
+}
+
+static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
+	struct datapath *dp;
+	struct flow_table *table;
+
+	dp = get_dp(ovs_header->dp_ifindex);
+	if (!dp)
+		return -ENODEV;
+
+	table = genl_dereference(dp->table);
+
+	for (;;) {
+		struct sw_flow *flow;
+		u32 bucket, obj;
+
+		bucket = cb->args[0];
+		obj = cb->args[1];
+		flow = ovs_flow_tbl_next(table, &bucket, &obj);
+		if (!flow)
+			break;
+
+		if (ovs_flow_cmd_fill_info(flow, dp, skb,
+					   NETLINK_CB(cb->skb).pid,
+					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
+					   OVS_FLOW_CMD_NEW) < 0)
+			break;
+
+		cb->args[0] = bucket;
+		cb->args[1] = obj;
+	}
+	return skb->len;
+}
+
+static struct genl_ops dp_flow_genl_ops[] = {
+	{ .cmd = OVS_FLOW_CMD_NEW,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = flow_policy,
+	  .doit = ovs_flow_cmd_new_or_set
+	},
+	{ .cmd = OVS_FLOW_CMD_DEL,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = flow_policy,
+	  .doit = ovs_flow_cmd_del
+	},
+	{ .cmd = OVS_FLOW_CMD_GET,
+	  .flags = 0,		    /* OK for unprivileged users. */
+	  .policy = flow_policy,
+	  .doit = ovs_flow_cmd_get,
+	  .dumpit = ovs_flow_cmd_dump
+	},
+	{ .cmd = OVS_FLOW_CMD_SET,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = flow_policy,
+	  .doit = ovs_flow_cmd_new_or_set,
+	},
+};
+
+static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
+	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
+	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
+};
+
+static struct genl_family dp_datapath_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = sizeof(struct ovs_header),
+	.name = OVS_DATAPATH_FAMILY,
+	.version = OVS_DATAPATH_VERSION,
+	.maxattr = OVS_DP_ATTR_MAX
+};
+
+static struct genl_multicast_group ovs_dp_datapath_multicast_group = {
+	.name = OVS_DATAPATH_MCGROUP
+};
+
+static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
+				u32 pid, u32 seq, u32 flags, u8 cmd)
+{
+	struct ovs_header *ovs_header;
+	struct ovs_dp_stats dp_stats;
+	int err;
+
+	ovs_header = genlmsg_put(skb, pid, seq, &dp_datapath_genl_family,
+				   flags, cmd);
+	if (!ovs_header)
+		goto error;
+
+	ovs_header->dp_ifindex = get_dpifindex(dp);
+
+	rcu_read_lock();
+	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
+	rcu_read_unlock();
+	if (err)
+		goto nla_put_failure;
+
+	get_dp_stats(dp, &dp_stats);
+	NLA_PUT(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats), &dp_stats);
+
+	return genlmsg_end(skb, ovs_header);
+
+nla_put_failure:
+	genlmsg_cancel(skb, ovs_header);
+error:
+	return -EMSGSIZE;
+}
+
+static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 pid,
+					     u32 seq, u8 cmd)
+{
+	struct sk_buff *skb;
+	int retval;
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!skb)
+		return ERR_PTR(-ENOMEM);
+
+	retval = ovs_dp_cmd_fill_info(dp, skb, pid, seq, 0, cmd);
+	if (retval < 0) {
+		kfree_skb(skb);
+		return ERR_PTR(retval);
+	}
+	return skb;
+}
+
+/* Called with genl_mutex and optionally with RTNL lock also. */
+static struct datapath *lookup_datapath(struct ovs_header *ovs_header,
+					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
+{
+	struct datapath *dp;
+
+	if (!a[OVS_DP_ATTR_NAME])
+		dp = get_dp(ovs_header->dp_ifindex);
+	else {
+		struct vport *vport;
+
+		rcu_read_lock();
+		vport = ovs_vport_locate(nla_data(a[OVS_DP_ATTR_NAME]));
+		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
+		rcu_read_unlock();
+	}
+	return dp ? dp : ERR_PTR(-ENODEV);
+}
+
+static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct vport_parms parms;
+	struct sk_buff *reply;
+	struct datapath *dp;
+	struct vport *vport;
+	int err;
+
+	err = -EINVAL;
+	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
+		goto err;
+
+	rtnl_lock();
+	err = -ENODEV;
+	if (!try_module_get(THIS_MODULE))
+		goto err_unlock_rtnl;
+
+	err = -ENOMEM;
+	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+	if (dp == NULL)
+		goto err_put_module;
+	INIT_LIST_HEAD(&dp->port_list);
+
+	/* Allocate table. */
+	err = -ENOMEM;
+	rcu_assign_pointer(dp->table, ovs_flow_tbl_alloc(TBL_MIN_BUCKETS));
+	if (!dp->table)
+		goto err_free_dp;
+
+	dp->stats_percpu = alloc_percpu(struct dp_stats_percpu);
+	if (!dp->stats_percpu) {
+		err = -ENOMEM;
+		goto err_destroy_table;
+	}
+
+	/* Set up our datapath device. */
+	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
+	parms.type = OVS_VPORT_TYPE_INTERNAL;
+	parms.options = NULL;
+	parms.dp = dp;
+	parms.port_no = OVSP_LOCAL;
+	parms.upcall_pid = nla_get_u32(a[OVS_DP_ATTR_UPCALL_PID]);
+
+	vport = new_vport(&parms);
+	if (IS_ERR(vport)) {
+		err = PTR_ERR(vport);
+		if (err == -EBUSY)
+			err = -EEXIST;
+
+		goto err_destroy_percpu;
+	}
+
+	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
+				      info->snd_seq, OVS_DP_CMD_NEW);
+	err = PTR_ERR(reply);
+	if (IS_ERR(reply))
+		goto err_destroy_local_port;
+
+	list_add_tail(&dp->list_node, &dps);
+	rtnl_unlock();
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
+		    GFP_KERNEL);
+	return 0;
+
+err_destroy_local_port:
+	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
+err_destroy_percpu:
+	free_percpu(dp->stats_percpu);
+err_destroy_table:
+	ovs_flow_tbl_destroy(genl_dereference(dp->table));
+err_free_dp:
+	kfree(dp);
+err_put_module:
+	module_put(THIS_MODULE);
+err_unlock_rtnl:
+	rtnl_unlock();
+err:
+	return err;
+}
+
+static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
+{
+	struct vport *vport, *next_vport;
+	struct sk_buff *reply;
+	struct datapath *dp;
+	int err;
+
+	rtnl_lock();
+	dp = lookup_datapath(info->userhdr, info->attrs);
+	err = PTR_ERR(dp);
+	if (IS_ERR(dp))
+		goto exit_unlock;
+
+	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
+				      info->snd_seq, OVS_DP_CMD_DEL);
+	err = PTR_ERR(reply);
+	if (IS_ERR(reply))
+		goto exit_unlock;
+
+	list_for_each_entry_safe(vport, next_vport, &dp->port_list, node)
+		if (vport->port_no != OVSP_LOCAL)
+			ovs_dp_detach_port(vport);
+
+	list_del(&dp->list_node);
+	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
+
+	/* rtnl_unlock() will wait until all the references to devices that
+	 * are pending unregistration have been dropped.  We do it here to
+	 * ensure that any internal devices (which contain DP pointers) are
+	 * fully destroyed before freeing the datapath.
+	 */
+	rtnl_unlock();
+
+	call_rcu(&dp->rcu, destroy_dp_rcu);
+	module_put(THIS_MODULE);
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
+		    GFP_KERNEL);
+
+	return 0;
+
+exit_unlock:
+	rtnl_unlock();
+	return err;
+}
+
+static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
+{
+	struct sk_buff *reply;
+	struct datapath *dp;
+	int err;
+
+	dp = lookup_datapath(info->userhdr, info->attrs);
+	if (IS_ERR(dp))
+		return PTR_ERR(dp);
+
+	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
+				      info->snd_seq, OVS_DP_CMD_NEW);
+	if (IS_ERR(reply)) {
+		err = PTR_ERR(reply);
+		netlink_set_err(init_net.genl_sock, 0,
+				ovs_dp_datapath_multicast_group.id, err);
+		return 0;
+	}
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
+		    GFP_KERNEL);
+
+	return 0;
+}
+
+static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
+{
+	struct sk_buff *reply;
+	struct datapath *dp;
+
+	dp = lookup_datapath(info->userhdr, info->attrs);
+	if (IS_ERR(dp))
+		return PTR_ERR(dp);
+
+	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
+				      info->snd_seq, OVS_DP_CMD_NEW);
+	if (IS_ERR(reply))
+		return PTR_ERR(reply);
+
+	return genlmsg_reply(reply, info);
+}
+
+static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct datapath *dp;
+	int skip = cb->args[0];
+	int i = 0;
+
+	list_for_each_entry(dp, &dps, list_node) {
+		if (i < skip)
+			continue;
+		if (ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).pid,
+					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
+					 OVS_DP_CMD_NEW) < 0)
+			break;
+		i++;
+	}
+
+	cb->args[0] = i;
+
+	return skb->len;
+}
+
+static struct genl_ops dp_datapath_genl_ops[] = {
+	{ .cmd = OVS_DP_CMD_NEW,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = datapath_policy,
+	  .doit = ovs_dp_cmd_new
+	},
+	{ .cmd = OVS_DP_CMD_DEL,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = datapath_policy,
+	  .doit = ovs_dp_cmd_del
+	},
+	{ .cmd = OVS_DP_CMD_GET,
+	  .flags = 0,		    /* OK for unprivileged users. */
+	  .policy = datapath_policy,
+	  .doit = ovs_dp_cmd_get,
+	  .dumpit = ovs_dp_cmd_dump
+	},
+	{ .cmd = OVS_DP_CMD_SET,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = datapath_policy,
+	  .doit = ovs_dp_cmd_set,
+	},
+};
+
+static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
+	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
+	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
+	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
+	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
+	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
+	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
+};
+
+static struct genl_family dp_vport_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = sizeof(struct ovs_header),
+	.name = OVS_VPORT_FAMILY,
+	.version = OVS_VPORT_VERSION,
+	.maxattr = OVS_VPORT_ATTR_MAX
+};
+
+struct genl_multicast_group ovs_dp_vport_multicast_group = {
+	.name = OVS_VPORT_MCGROUP
+};
+
+/* Called with RTNL lock or RCU read lock. */
+static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
+				   u32 pid, u32 seq, u32 flags, u8 cmd)
+{
+	struct ovs_header *ovs_header;
+	struct ovs_vport_stats vport_stats;
+	int err;
+
+	ovs_header = genlmsg_put(skb, pid, seq, &dp_vport_genl_family,
+				 flags, cmd);
+	if (!ovs_header)
+		return -EMSGSIZE;
+
+	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
+
+	NLA_PUT_U32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no);
+	NLA_PUT_U32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type);
+	NLA_PUT_STRING(skb, OVS_VPORT_ATTR_NAME, vport->ops->get_name(vport));
+	NLA_PUT_U32(skb, OVS_VPORT_ATTR_UPCALL_PID, vport->upcall_pid);
+
+	ovs_vport_get_stats(vport, &vport_stats);
+	NLA_PUT(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
+		&vport_stats);
+
+	err = ovs_vport_get_options(vport, skb);
+	if (err == -EMSGSIZE)
+		goto error;
+
+	return genlmsg_end(skb, ovs_header);
+
+nla_put_failure:
+	err = -EMSGSIZE;
+error:
+	genlmsg_cancel(skb, ovs_header);
+	return err;
+}
+
+/* Called with RTNL lock or RCU read lock. */
+struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 pid,
+					 u32 seq, u8 cmd)
+{
+	struct sk_buff *skb;
+	int retval;
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+	if (!skb)
+		return ERR_PTR(-ENOMEM);
+
+	retval = ovs_vport_cmd_fill_info(vport, skb, pid, seq, 0, cmd);
+	if (retval < 0) {
+		kfree_skb(skb);
+		return ERR_PTR(retval);
+	}
+	return skb;
+}
+
+/* Called with RTNL lock or RCU read lock. */
+static struct vport *lookup_vport(struct ovs_header *ovs_header,
+				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
+{
+	struct datapath *dp;
+	struct vport *vport;
+
+	if (a[OVS_VPORT_ATTR_NAME]) {
+		vport = ovs_vport_locate(nla_data(a[OVS_VPORT_ATTR_NAME]));
+		if (!vport)
+			return ERR_PTR(-ENODEV);
+		return vport;
+	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
+		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
+
+		if (port_no >= DP_MAX_PORTS)
+			return ERR_PTR(-EFBIG);
+
+		dp = get_dp(ovs_header->dp_ifindex);
+		if (!dp)
+			return ERR_PTR(-ENODEV);
+
+		vport = rcu_dereference_rtnl(dp->ports[port_no]);
+		if (!vport)
+			return ERR_PTR(-ENOENT);
+		return vport;
+	} else
+		return ERR_PTR(-EINVAL);
+}
+
+static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct ovs_header *ovs_header = info->userhdr;
+	struct vport_parms parms;
+	struct sk_buff *reply;
+	struct vport *vport;
+	struct datapath *dp;
+	u32 port_no;
+	int err;
+
+	err = -EINVAL;
+	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
+	    !a[OVS_VPORT_ATTR_UPCALL_PID])
+		goto exit;
+
+	rtnl_lock();
+	dp = get_dp(ovs_header->dp_ifindex);
+	err = -ENODEV;
+	if (!dp)
+		goto exit_unlock;
+
+	if (a[OVS_VPORT_ATTR_PORT_NO]) {
+		port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
+
+		err = -EFBIG;
+		if (port_no >= DP_MAX_PORTS)
+			goto exit_unlock;
+
+		vport = rtnl_dereference(dp->ports[port_no]);
+		err = -EBUSY;
+		if (vport)
+			goto exit_unlock;
+	} else {
+		for (port_no = 1; ; port_no++) {
+			if (port_no >= DP_MAX_PORTS) {
+				err = -EFBIG;
+				goto exit_unlock;
+			}
+			vport = rtnl_dereference(dp->ports[port_no]);
+			if (!vport)
+				break;
+		}
+	}
+
+	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
+	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
+	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
+	parms.dp = dp;
+	parms.port_no = port_no;
+	parms.upcall_pid = nla_get_u32(a[OVS_VPORT_ATTR_UPCALL_PID]);
+
+	vport = new_vport(&parms);
+	err = PTR_ERR(vport);
+	if (IS_ERR(vport))
+		goto exit_unlock;
+
+	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
+					 OVS_VPORT_CMD_NEW);
+	if (IS_ERR(reply)) {
+		err = PTR_ERR(reply);
+		ovs_dp_detach_port(vport);
+		goto exit_unlock;
+	}
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
+
+exit_unlock:
+	rtnl_unlock();
+exit:
+	return err;
+}
+
+static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct sk_buff *reply;
+	struct vport *vport;
+	int err;
+
+	rtnl_lock();
+	vport = lookup_vport(info->userhdr, a);
+	err = PTR_ERR(vport);
+	if (IS_ERR(vport))
+		goto exit_unlock;
+
+	err = 0;
+	if (a[OVS_VPORT_ATTR_TYPE] &&
+	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type)
+		err = -EINVAL;
+
+	if (!err && a[OVS_VPORT_ATTR_OPTIONS])
+		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
+	if (!err && a[OVS_VPORT_ATTR_UPCALL_PID])
+		vport->upcall_pid = nla_get_u32(a[OVS_VPORT_ATTR_UPCALL_PID]);
+
+	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
+					 OVS_VPORT_CMD_NEW);
+	if (IS_ERR(reply)) {
+		err = PTR_ERR(reply);
+		netlink_set_err(init_net.genl_sock, 0,
+				ovs_dp_vport_multicast_group.id, err);
+		return 0;
+	}
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
+
+exit_unlock:
+	rtnl_unlock();
+	return err;
+}
+
+static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct sk_buff *reply;
+	struct vport *vport;
+	int err;
+
+	rtnl_lock();
+	vport = lookup_vport(info->userhdr, a);
+	err = PTR_ERR(vport);
+	if (IS_ERR(vport))
+		goto exit_unlock;
+
+	if (vport->port_no == OVSP_LOCAL) {
+		err = -EINVAL;
+		goto exit_unlock;
+	}
+
+	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
+					 OVS_VPORT_CMD_DEL);
+	err = PTR_ERR(reply);
+	if (IS_ERR(reply))
+		goto exit_unlock;
+
+	ovs_dp_detach_port(vport);
+
+	genl_notify(reply, genl_info_net(info), info->snd_pid,
+		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
+
+exit_unlock:
+	rtnl_unlock();
+	return err;
+}
+
+static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr **a = info->attrs;
+	struct ovs_header *ovs_header = info->userhdr;
+	struct sk_buff *reply;
+	struct vport *vport;
+	int err;
+
+	rcu_read_lock();
+	vport = lookup_vport(ovs_header, a);
+	err = PTR_ERR(vport);
+	if (IS_ERR(vport))
+		goto exit_unlock;
+
+	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
+					 OVS_VPORT_CMD_NEW);
+	err = PTR_ERR(reply);
+	if (IS_ERR(reply))
+		goto exit_unlock;
+
+	rcu_read_unlock();
+
+	return genlmsg_reply(reply, info);
+
+exit_unlock:
+	rcu_read_unlock();
+	return err;
+}
+
+static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
+	struct datapath *dp;
+	u32 port_no;
+	int retval;
+
+	dp = get_dp(ovs_header->dp_ifindex);
+	if (!dp)
+		return -ENODEV;
+
+	rcu_read_lock();
+	for (port_no = cb->args[0]; port_no < DP_MAX_PORTS; port_no++) {
+		struct vport *vport;
+
+		vport = rcu_dereference(dp->ports[port_no]);
+		if (!vport)
+			continue;
+
+		if (ovs_vport_cmd_fill_info(vport, skb, NETLINK_CB(cb->skb).pid,
+					    cb->nlh->nlmsg_seq, NLM_F_MULTI,
+					    OVS_VPORT_CMD_NEW) < 0)
+			break;
+	}
+	rcu_read_unlock();
+
+	cb->args[0] = port_no;
+	retval = skb->len;
+
+	return retval;
+}
+
+static void rehash_flow_table(struct work_struct *work)
+{
+	struct datapath *dp;
+
+	genl_lock();
+
+	list_for_each_entry(dp, &dps, list_node) {
+		struct flow_table *old_table = genl_dereference(dp->table);
+		struct flow_table *new_table;
+
+		new_table = ovs_flow_tbl_rehash(old_table);
+		if (!IS_ERR(new_table)) {
+			rcu_assign_pointer(dp->table, new_table);
+			ovs_flow_tbl_deferred_destroy(old_table);
+		}
+	}
+
+	genl_unlock();
+
+	schedule_delayed_work(&rehash_flow_wq, REHASH_FLOW_INTERVAL);
+}
+
+static struct genl_ops dp_vport_genl_ops[] = {
+	{ .cmd = OVS_VPORT_CMD_NEW,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = vport_policy,
+	  .doit = ovs_vport_cmd_new
+	},
+	{ .cmd = OVS_VPORT_CMD_DEL,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = vport_policy,
+	  .doit = ovs_vport_cmd_del
+	},
+	{ .cmd = OVS_VPORT_CMD_GET,
+	  .flags = 0,		    /* OK for unprivileged users. */
+	  .policy = vport_policy,
+	  .doit = ovs_vport_cmd_get,
+	  .dumpit = ovs_vport_cmd_dump
+	},
+	{ .cmd = OVS_VPORT_CMD_SET,
+	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
+	  .policy = vport_policy,
+	  .doit = ovs_vport_cmd_set,
+	},
+};
+
+struct genl_family_and_ops {
+	struct genl_family *family;
+	struct genl_ops *ops;
+	int n_ops;
+	struct genl_multicast_group *group;
+};
+
+static const struct genl_family_and_ops dp_genl_families[] = {
+	{ &dp_datapath_genl_family,
+	  dp_datapath_genl_ops, ARRAY_SIZE(dp_datapath_genl_ops),
+	  &ovs_dp_datapath_multicast_group },
+	{ &dp_vport_genl_family,
+	  dp_vport_genl_ops, ARRAY_SIZE(dp_vport_genl_ops),
+	  &ovs_dp_vport_multicast_group },
+	{ &dp_flow_genl_family,
+	  dp_flow_genl_ops, ARRAY_SIZE(dp_flow_genl_ops),
+	  &ovs_dp_flow_multicast_group },
+	{ &dp_packet_genl_family,
+	  dp_packet_genl_ops, ARRAY_SIZE(dp_packet_genl_ops),
+	  NULL },
+};
+
+static void dp_unregister_genl(int n_families)
+{
+	int i;
+
+	for (i = 0; i < n_families; i++)
+		genl_unregister_family(dp_genl_families[i].family);
+}
+
+static int dp_register_genl(void)
+{
+	int n_registered;
+	int err;
+	int i;
+
+	n_registered = 0;
+	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
+		const struct genl_family_and_ops *f = &dp_genl_families[i];
+
+		err = genl_register_family_with_ops(f->family, f->ops,
+						    f->n_ops);
+		if (err)
+			goto error;
+		n_registered++;
+
+		if (f->group) {
+			err = genl_register_mc_group(f->family, f->group);
+			if (err)
+				goto error;
+		}
+	}
+
+	return 0;
+
+error:
+	dp_unregister_genl(n_registered);
+	return err;
+}
+
+static int __init dp_init(void)
+{
+	struct sk_buff *dummy_skb;
+	int err;
+
+	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > sizeof(dummy_skb->cb));
+
+	pr_info("Open vSwitch switching datapath\n");
+
+	err = ovs_flow_init();
+	if (err)
+		goto error;
+
+	err = ovs_vport_init();
+	if (err)
+		goto error_flow_exit;
+
+	err = register_netdevice_notifier(&ovs_dp_device_notifier);
+	if (err)
+		goto error_vport_exit;
+
+	err = dp_register_genl();
+	if (err < 0)
+		goto error_unreg_notifier;
+
+	schedule_delayed_work(&rehash_flow_wq, REHASH_FLOW_INTERVAL);
+
+	return 0;
+
+error_unreg_notifier:
+	unregister_netdevice_notifier(&ovs_dp_device_notifier);
+error_vport_exit:
+	ovs_vport_exit();
+error_flow_exit:
+	ovs_flow_exit();
+error:
+	return err;
+}
+
+static void dp_cleanup(void)
+{
+	cancel_delayed_work_sync(&rehash_flow_wq);
+	rcu_barrier();
+	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
+	unregister_netdevice_notifier(&ovs_dp_device_notifier);
+	ovs_vport_exit();
+	ovs_flow_exit();
+}
+
+module_init(dp_init);
+module_exit(dp_cleanup);
+
+MODULE_DESCRIPTION("Open vSwitch switching datapath");
+MODULE_LICENSE("GPL");