net/openvswitch/datapath.h

   1 /*
   2  * Copyright (c) 2007-2012 Nicira, Inc.
   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
  29 #include "flow.h"
  30
  31 struct vport;
  32
  33 #define DP_MAX_PORTS 1024
  34 #define SAMPLE_ACTION_DEPTH 3
  35
  36 /**
  37  * struct dp_stats_percpu - per-cpu packet processing statistics for a given
  38  * datapath.
  39  * @n_hit: Number of received packets for which a matching flow was found in
  40  * the flow table.
  41  * @n_miss: Number of received packets that had no matching flow in the flow
  42  * table.  The sum of @n_hit and @n_miss is the number of packets that have
  43  * been received by the datapath.
  44  * @n_lost: Number of received packets that had no matching flow in the flow
  45  * table that could not be sent to userspace (normally due to an overflow in
  46  * one of the datapath's queues).
  47  */
  48 struct dp_stats_percpu {
  49         u64 n_hit;
  50         u64 n_missed;
  51         u64 n_lost;
  52         struct u64_stats_sync sync;
  53 };
  54
  55 /**
  56  * struct datapath - datapath for flow-based packet switching
  57  * @rcu: RCU callback head for deferred destruction.
  58  * @list_node: Element in global 'dps' list.
  59  * @n_flows: Number of flows currently in flow table.
  60  * @table: Current flow table.  Protected by genl_lock and RCU.
  61  * @ports: Map from port number to &struct vport.  %OVSP_LOCAL port
  62  * always exists, other ports may be %NULL.  Protected by RTNL and RCU.
  63  * @port_list: List of all ports in @ports in arbitrary order.  RTNL required
  64  * to iterate or modify.
  65  * @stats_percpu: Per-CPU datapath statistics.
  66  *
  67  * Context: See the comment on locking at the top of datapath.c for additional
  68  * locking information.
  69  */
  70 struct datapath {
  71         struct rcu_head rcu;
  72         struct list_head list_node;
  73
  74         /* Flow table. */
  75         struct flow_table __rcu *table;
  76
  77         /* Switch ports. */
  78         struct vport __rcu *ports[DP_MAX_PORTS];
  79         struct list_head port_list;
  80
  81         /* Stats. */
  82         struct dp_stats_percpu __percpu *stats_percpu;
  83 };
  84
  85 /**
  86  * struct ovs_skb_cb - OVS data in skb CB
  87  * @flow: The flow associated with this packet.  May be %NULL if no flow.
  88  */
  89 struct ovs_skb_cb {
  90         struct sw_flow          *flow;
  91 };
  92 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
  93
  94 /**
  95  * struct dp_upcall - metadata to include with a packet to send to userspace
  96  * @cmd: One of %OVS_PACKET_CMD_*.
  97  * @key: Becomes %OVS_PACKET_ATTR_KEY.  Must be nonnull.
  98  * @userdata: If nonnull, its u64 value is extracted and passed to userspace as
  99  * %OVS_PACKET_ATTR_USERDATA.
 100  * @pid: Netlink PID to which packet should be sent.  If @pid is 0 then no
 101  * packet is sent and the packet is accounted in the datapath's @n_lost
 102  * counter.
 103  */
 104 struct dp_upcall_info {
 105         u8 cmd;
 106         const struct sw_flow_key *key;
 107         const struct nlattr *userdata;
 108         u32 pid;
 109 };
 110
 111 extern struct notifier_block ovs_dp_device_notifier;
 112 extern struct genl_multicast_group ovs_dp_vport_multicast_group;
 113
 114 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
 115 void ovs_dp_detach_port(struct vport *);
 116 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
 117                   const struct dp_upcall_info *);
 118
 119 const char *ovs_dp_name(const struct datapath *dp);
 120 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq,
 121                                          u8 cmd);
 122
 123 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb);
 124 #endif /* datapath.h */