xref: /linux/net/openvswitch/datapath.h (revision 90ab5ee94171b3e28de6bb42ee30b527014e0be7)
1 /*
2  * Copyright (c) 2007-2011 Nicira Networks.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of version 2 of the GNU General Public
6  * License as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16  * 02110-1301, USA
17  */
18 
19 #ifndef DATAPATH_H
20 #define DATAPATH_H 1
21 
22 #include <asm/page.h>
23 #include <linux/kernel.h>
24 #include <linux/mutex.h>
25 #include <linux/netdevice.h>
26 #include <linux/skbuff.h>
27 #include <linux/u64_stats_sync.h>
28 #include <linux/version.h>
29 
30 #include "flow.h"
31 
32 struct vport;
33 
34 #define DP_MAX_PORTS 1024
35 #define SAMPLE_ACTION_DEPTH 3
36 
37 /**
38  * struct dp_stats_percpu - per-cpu packet processing statistics for a given
39  * datapath.
40  * @n_hit: Number of received packets for which a matching flow was found in
41  * the flow table.
42  * @n_miss: Number of received packets that had no matching flow in the flow
43  * table.  The sum of @n_hit and @n_miss is the number of packets that have
44  * been received by the datapath.
45  * @n_lost: Number of received packets that had no matching flow in the flow
46  * table that could not be sent to userspace (normally due to an overflow in
47  * one of the datapath's queues).
48  */
49 struct dp_stats_percpu {
50 	u64 n_hit;
51 	u64 n_missed;
52 	u64 n_lost;
53 	struct u64_stats_sync sync;
54 };
55 
56 /**
57  * struct datapath - datapath for flow-based packet switching
58  * @rcu: RCU callback head for deferred destruction.
59  * @list_node: Element in global 'dps' list.
60  * @n_flows: Number of flows currently in flow table.
61  * @table: Current flow table.  Protected by genl_lock and RCU.
62  * @ports: Map from port number to &struct vport.  %OVSP_LOCAL port
63  * always exists, other ports may be %NULL.  Protected by RTNL and RCU.
64  * @port_list: List of all ports in @ports in arbitrary order.  RTNL required
65  * to iterate or modify.
66  * @stats_percpu: Per-CPU datapath statistics.
67  *
68  * Context: See the comment on locking at the top of datapath.c for additional
69  * locking information.
70  */
71 struct datapath {
72 	struct rcu_head rcu;
73 	struct list_head list_node;
74 
75 	/* Flow table. */
76 	struct flow_table __rcu *table;
77 
78 	/* Switch ports. */
79 	struct vport __rcu *ports[DP_MAX_PORTS];
80 	struct list_head port_list;
81 
82 	/* Stats. */
83 	struct dp_stats_percpu __percpu *stats_percpu;
84 };
85 
86 /**
87  * struct ovs_skb_cb - OVS data in skb CB
88  * @flow: The flow associated with this packet.  May be %NULL if no flow.
89  */
90 struct ovs_skb_cb {
91 	struct sw_flow		*flow;
92 };
93 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
94 
95 /**
96  * struct dp_upcall - metadata to include with a packet to send to userspace
97  * @cmd: One of %OVS_PACKET_CMD_*.
98  * @key: Becomes %OVS_PACKET_ATTR_KEY.  Must be nonnull.
99  * @userdata: If nonnull, its u64 value is extracted and passed to userspace as
100  * %OVS_PACKET_ATTR_USERDATA.
101  * @pid: Netlink PID to which packet should be sent.  If @pid is 0 then no
102  * packet is sent and the packet is accounted in the datapath's @n_lost
103  * counter.
104  */
105 struct dp_upcall_info {
106 	u8 cmd;
107 	const struct sw_flow_key *key;
108 	const struct nlattr *userdata;
109 	u32 pid;
110 };
111 
112 extern struct notifier_block ovs_dp_device_notifier;
113 extern struct genl_multicast_group ovs_dp_vport_multicast_group;
114 
115 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
116 void ovs_dp_detach_port(struct vport *);
117 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
118 		  const struct dp_upcall_info *);
119 
120 const char *ovs_dp_name(const struct datapath *dp);
121 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq,
122 					 u8 cmd);
123 
124 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb);
125 #endif /* datapath.h */
126