net/openvswitch/datapath.h

   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 */