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 * @table: Current flow table. Protected by ovs_mutex and RCU. 61 * @ports: Hash table for ports. %OVSP_LOCAL port always exists. Protected by 62 * ovs_mutex and RCU. 63 * @stats_percpu: Per-CPU datapath statistics. 64 * @net: Reference to net namespace. 65 * 66 * Context: See the comment on locking at the top of datapath.c for additional 67 * locking information. 68 */ 69 struct datapath { 70 struct rcu_head rcu; 71 struct list_head list_node; 72 73 /* Flow table. */ 74 struct flow_table __rcu *table; 75 76 /* Switch ports. */ 77 struct hlist_head *ports; 78 79 /* Stats. */ 80 struct dp_stats_percpu __percpu *stats_percpu; 81 82 #ifdef CONFIG_NET_NS 83 /* Network namespace ref. */ 84 struct net *net; 85 #endif 86 }; 87 88 /** 89 * struct ovs_skb_cb - OVS data in skb CB 90 * @flow: The flow associated with this packet. May be %NULL if no flow. 91 * @pkt_key: The flow information extracted from the packet. Must be nonnull. 92 * @tun_key: Key for the tunnel that encapsulated this packet. NULL if the 93 * packet is not being tunneled. 94 */ 95 struct ovs_skb_cb { 96 struct sw_flow *flow; 97 struct sw_flow_key *pkt_key; 98 struct ovs_key_ipv4_tunnel *tun_key; 99 }; 100 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) 101 102 /** 103 * struct dp_upcall - metadata to include with a packet to send to userspace 104 * @cmd: One of %OVS_PACKET_CMD_*. 105 * @key: Becomes %OVS_PACKET_ATTR_KEY. Must be nonnull. 106 * @userdata: If nonnull, its variable-length value is passed to userspace as 107 * %OVS_PACKET_ATTR_USERDATA. 108 * @pid: Netlink PID to which packet should be sent. If @pid is 0 then no 109 * packet is sent and the packet is accounted in the datapath's @n_lost 110 * counter. 111 */ 112 struct dp_upcall_info { 113 u8 cmd; 114 const struct sw_flow_key *key; 115 const struct nlattr *userdata; 116 u32 portid; 117 }; 118 119 /** 120 * struct ovs_net - Per net-namespace data for ovs. 121 * @dps: List of datapaths to enable dumping them all out. 122 * Protected by genl_mutex. 123 */ 124 struct ovs_net { 125 struct list_head dps; 126 struct work_struct dp_notify_work; 127 struct vport_net vport_net; 128 }; 129 130 extern int ovs_net_id; 131 void ovs_lock(void); 132 void ovs_unlock(void); 133 134 #ifdef CONFIG_LOCKDEP 135 int lockdep_ovsl_is_held(void); 136 #else 137 #define lockdep_ovsl_is_held() 1 138 #endif 139 140 #define ASSERT_OVSL() WARN_ON(unlikely(!lockdep_ovsl_is_held())) 141 #define ovsl_dereference(p) \ 142 rcu_dereference_protected(p, lockdep_ovsl_is_held()) 143 144 static inline struct net *ovs_dp_get_net(struct datapath *dp) 145 { 146 return read_pnet(&dp->net); 147 } 148 149 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) 150 { 151 write_pnet(&dp->net, net); 152 } 153 154 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); 155 156 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) 157 { 158 WARN_ON_ONCE(!rcu_read_lock_held()); 159 return ovs_lookup_vport(dp, port_no); 160 } 161 162 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no) 163 { 164 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); 165 return ovs_lookup_vport(dp, port_no); 166 } 167 168 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no) 169 { 170 ASSERT_OVSL(); 171 return ovs_lookup_vport(dp, port_no); 172 } 173 174 extern struct notifier_block ovs_dp_device_notifier; 175 extern struct genl_multicast_group ovs_dp_vport_multicast_group; 176 177 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *); 178 void ovs_dp_detach_port(struct vport *); 179 int ovs_dp_upcall(struct datapath *, struct sk_buff *, 180 const struct dp_upcall_info *); 181 182 const char *ovs_dp_name(const struct datapath *dp); 183 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq, 184 u8 cmd); 185 186 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb); 187 void ovs_dp_notify_wq(struct work_struct *work); 188 189 #define OVS_NLERR(fmt, ...) \ 190 pr_info_once("netlink: " fmt, ##__VA_ARGS__) 191 192 #endif /* datapath.h */ 193