datapath.h
/*
* Copyright (c) 2007-2012 Nicira, Inc.
*
* 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 "flow.h"
#include "vport.h"
#define DP_MAX_PORTS USHRT_MAX
#define DP_VPORT_HASH_BUCKETS 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: Hash table for ports. %OVSP_LOCAL port always exists. Protected by
* RTNL and RCU.
* @stats_percpu: Per-CPU datapath statistics.
* @net: Reference to net namespace.
*
* 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 hlist_head *ports;
/* Stats. */
struct dp_stats_percpu __percpu *stats_percpu;
#ifdef CONFIG_NET_NS
/* Network namespace ref. */
struct net *net;
#endif
};
struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no);
static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no)
{
WARN_ON_ONCE(!rcu_read_lock_held());
return ovs_lookup_vport(dp, port_no);
}
static inline struct vport *ovs_vport_rtnl_rcu(const struct datapath *dp, int port_no)
{
WARN_ON_ONCE(!rcu_read_lock_held() && !rtnl_is_locked());
return ovs_lookup_vport(dp, port_no);
}
static inline struct vport *ovs_vport_rtnl(const struct datapath *dp, int port_no)
{
ASSERT_RTNL();
return ovs_lookup_vport(dp, port_no);
}
/**
* 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 portid;
};
static inline struct net *ovs_dp_get_net(struct datapath *dp)
{
return read_pnet(&dp->net);
}
static inline void ovs_dp_set_net(struct datapath *dp, struct net *net)
{
write_pnet(&dp->net, net);
}
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 */