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 #include "vport.h" 31 32 #define DP_MAX_PORTS USHRT_MAX 33 #define DP_VPORT_HASH_BUCKETS 1024 34 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: Hash table for ports. %OVSP_LOCAL port always exists. Protected by 63 * RTNL and RCU. 64 * @stats_percpu: Per-CPU datapath statistics. 65 * @net: Reference to net namespace. 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 hlist_head *ports; 79 80 /* Stats. */ 81 struct dp_stats_percpu __percpu *stats_percpu; 82 83 #ifdef CONFIG_NET_NS 84 /* Network namespace ref. */ 85 struct net *net; 86 #endif 87 }; 88 89 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); 90 91 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) 92 { 93 WARN_ON_ONCE(!rcu_read_lock_held()); 94 return ovs_lookup_vport(dp, port_no); 95 } 96 97 static inline struct vport *ovs_vport_rtnl_rcu(const struct datapath *dp, int port_no) 98 { 99 WARN_ON_ONCE(!rcu_read_lock_held() && !rtnl_is_locked()); 100 return ovs_lookup_vport(dp, port_no); 101 } 102 103 static inline struct vport *ovs_vport_rtnl(const struct datapath *dp, int port_no) 104 { 105 ASSERT_RTNL(); 106 return ovs_lookup_vport(dp, port_no); 107 } 108 109 /** 110 * struct ovs_skb_cb - OVS data in skb CB 111 * @flow: The flow associated with this packet. May be %NULL if no flow. 112 */ 113 struct ovs_skb_cb { 114 struct sw_flow *flow; 115 }; 116 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) 117 118 /** 119 * struct dp_upcall - metadata to include with a packet to send to userspace 120 * @cmd: One of %OVS_PACKET_CMD_*. 121 * @key: Becomes %OVS_PACKET_ATTR_KEY. Must be nonnull. 122 * @userdata: If nonnull, its u64 value is extracted and passed to userspace as 123 * %OVS_PACKET_ATTR_USERDATA. 124 * @pid: Netlink PID to which packet should be sent. If @pid is 0 then no 125 * packet is sent and the packet is accounted in the datapath's @n_lost 126 * counter. 127 */ 128 struct dp_upcall_info { 129 u8 cmd; 130 const struct sw_flow_key *key; 131 const struct nlattr *userdata; 132 u32 portid; 133 }; 134 135 static inline struct net *ovs_dp_get_net(struct datapath *dp) 136 { 137 return read_pnet(&dp->net); 138 } 139 140 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) 141 { 142 write_pnet(&dp->net, net); 143 } 144 145 extern struct notifier_block ovs_dp_device_notifier; 146 extern struct genl_multicast_group ovs_dp_vport_multicast_group; 147 148 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *); 149 void ovs_dp_detach_port(struct vport *); 150 int ovs_dp_upcall(struct datapath *, struct sk_buff *, 151 const struct dp_upcall_info *); 152 153 const char *ovs_dp_name(const struct datapath *dp); 154 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq, 155 u8 cmd); 156 157 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb); 158 #endif /* datapath.h */ 159