summaryrefslogtreecommitdiffstats
path: root/net/openvswitch/datapath.h
blob: 2b982fae6a11a8312c11d179c05c1f85a997ef1a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * 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 "flow_table.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).
 * @n_mask_hit: Number of masks looked up for flow match.
 *   @n_mask_hit / (@n_hit + @n_missed)  will be the average masks looked
 *   up per packet.
 */
struct dp_stats_percpu {
	u64 n_hit;
	u64 n_missed;
	u64 n_lost;
	u64 n_mask_hit;
	struct u64_stats_sync syncp;
};

/**
 * struct datapath - datapath for flow-based packet switching
 * @rcu: RCU callback head for deferred destruction.
 * @list_node: Element in global 'dps' list.
 * @table: flow table.
 * @ports: Hash table for ports.  %OVSP_LOCAL port always exists.  Protected by
 * ovs_mutex 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 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

	u32 user_features;
};

/**
 * struct ovs_skb_cb - OVS data in skb CB
 * @flow: The flow associated with this packet.  May be %NULL if no flow.
 * @tun_key: Key for the tunnel that encapsulated this packet. NULL if the
 * packet is not being tunneled.
 * @input_vport: The original vport packet came in on. This value is cached
 * when a packet is received by OVS.
 */
struct ovs_skb_cb {
	struct sw_flow		*flow;
	struct ovs_key_ipv4_tunnel  *tun_key;
	struct vport		*input_vport;
};
#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 variable-length value is 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;
};

/**
 * struct ovs_net - Per net-namespace data for ovs.
 * @dps: List of datapaths to enable dumping them all out.
 * Protected by genl_mutex.
 */
struct ovs_net {
	struct list_head dps;
	struct work_struct dp_notify_work;
	struct vport_net vport_net;
};

extern int ovs_net_id;
void ovs_lock(void);
void ovs_unlock(void);

#ifdef CONFIG_LOCKDEP
int lockdep_ovsl_is_held(void);
#else
#define lockdep_ovsl_is_held()	1
#endif

#define ASSERT_OVSL()		WARN_ON(!lockdep_ovsl_is_held())
#define ovsl_dereference(p)					\
	rcu_dereference_protected(p, lockdep_ovsl_is_held())
#define rcu_dereference_ovsl(p)					\
	rcu_dereference_check(p, lockdep_ovsl_is_held())

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);
}

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_ovsl_rcu(const struct datapath *dp, int port_no)
{
	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
	return ovs_lookup_vport(dp, port_no);
}

static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no)
{
	ASSERT_OVSL();
	return ovs_lookup_vport(dp, port_no);
}

extern struct notifier_block ovs_dp_device_notifier;
extern struct genl_family dp_vport_genl_family;

void ovs_dp_process_received_packet(struct sk_buff *);
void ovs_dp_detach_port(struct vport *);
int ovs_dp_upcall(struct datapath *, struct sk_buff *,
		  const struct dp_upcall_info *);

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,
			struct sw_flow_key *);
void ovs_dp_notify_wq(struct work_struct *work);

#define OVS_NLERR(fmt, ...)					\
do {								\
	if (net_ratelimit())					\
		pr_info("netlink: " fmt, ##__VA_ARGS__);	\
} while (0)
#endif /* datapath.h */