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 "flow_table.h" 31 #include "vport.h" 32 33 #define DP_MAX_PORTS USHRT_MAX 34 #define DP_VPORT_HASH_BUCKETS 1024 35 36 #define SAMPLE_ACTION_DEPTH 3 37 38 /** 39 * struct dp_stats_percpu - per-cpu packet processing statistics for a given 40 * datapath. 41 * @n_hit: Number of received packets for which a matching flow was found in 42 * the flow table. 43 * @n_miss: Number of received packets that had no matching flow in the flow 44 * table. The sum of @n_hit and @n_miss is the number of packets that have 45 * been received by the datapath. 46 * @n_lost: Number of received packets that had no matching flow in the flow 47 * table that could not be sent to userspace (normally due to an overflow in 48 * one of the datapath's queues). 49 * @n_mask_hit: Number of masks looked up for flow match. 50 * @n_mask_hit / (@n_hit + @n_missed) will be the average masks looked 51 * up per packet. 52 */ 53 struct dp_stats_percpu { 54 u64 n_hit; 55 u64 n_missed; 56 u64 n_lost; 57 u64 n_mask_hit; 58 struct u64_stats_sync sync; 59 }; 60 61 /** 62 * struct datapath - datapath for flow-based packet switching 63 * @rcu: RCU callback head for deferred destruction. 64 * @list_node: Element in global 'dps' list. 65 * @table: flow table. 66 * @ports: Hash table for ports. %OVSP_LOCAL port always exists. Protected by 67 * ovs_mutex and RCU. 68 * @stats_percpu: Per-CPU datapath statistics. 69 * @net: Reference to net namespace. 70 * 71 * Context: See the comment on locking at the top of datapath.c for additional 72 * locking information. 73 */ 74 struct datapath { 75 struct rcu_head rcu; 76 struct list_head list_node; 77 78 /* Flow table. */ 79 struct flow_table table; 80 81 /* Switch ports. */ 82 struct hlist_head *ports; 83 84 /* Stats. */ 85 struct dp_stats_percpu __percpu *stats_percpu; 86 87 #ifdef CONFIG_NET_NS 88 /* Network namespace ref. */ 89 struct net *net; 90 #endif 91 }; 92 93 /** 94 * struct ovs_skb_cb - OVS data in skb CB 95 * @flow: The flow associated with this packet. May be %NULL if no flow. 96 * @pkt_key: The flow information extracted from the packet. Must be nonnull. 97 * @tun_key: Key for the tunnel that encapsulated this packet. NULL if the 98 * packet is not being tunneled. 99 */ 100 struct ovs_skb_cb { 101 struct sw_flow *flow; 102 struct sw_flow_key *pkt_key; 103 struct ovs_key_ipv4_tunnel *tun_key; 104 }; 105 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) 106 107 /** 108 * struct dp_upcall - metadata to include with a packet to send to userspace 109 * @cmd: One of %OVS_PACKET_CMD_*. 110 * @key: Becomes %OVS_PACKET_ATTR_KEY. Must be nonnull. 111 * @userdata: If nonnull, its variable-length value is passed to userspace as 112 * %OVS_PACKET_ATTR_USERDATA. 113 * @pid: Netlink PID to which packet should be sent. If @pid is 0 then no 114 * packet is sent and the packet is accounted in the datapath's @n_lost 115 * counter. 116 */ 117 struct dp_upcall_info { 118 u8 cmd; 119 const struct sw_flow_key *key; 120 const struct nlattr *userdata; 121 u32 portid; 122 }; 123 124 /** 125 * struct ovs_net - Per net-namespace data for ovs. 126 * @dps: List of datapaths to enable dumping them all out. 127 * Protected by genl_mutex. 128 */ 129 struct ovs_net { 130 struct list_head dps; 131 struct work_struct dp_notify_work; 132 struct vport_net vport_net; 133 }; 134 135 extern int ovs_net_id; 136 void ovs_lock(void); 137 void ovs_unlock(void); 138 139 #ifdef CONFIG_LOCKDEP 140 int lockdep_ovsl_is_held(void); 141 #else 142 #define lockdep_ovsl_is_held() 1 143 #endif 144 145 #define ASSERT_OVSL() WARN_ON(unlikely(!lockdep_ovsl_is_held())) 146 #define ovsl_dereference(p) \ 147 rcu_dereference_protected(p, lockdep_ovsl_is_held()) 148 149 static inline struct net *ovs_dp_get_net(struct datapath *dp) 150 { 151 return read_pnet(&dp->net); 152 } 153 154 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) 155 { 156 write_pnet(&dp->net, net); 157 } 158 159 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); 160 161 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) 162 { 163 WARN_ON_ONCE(!rcu_read_lock_held()); 164 return ovs_lookup_vport(dp, port_no); 165 } 166 167 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no) 168 { 169 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); 170 return ovs_lookup_vport(dp, port_no); 171 } 172 173 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no) 174 { 175 ASSERT_OVSL(); 176 return ovs_lookup_vport(dp, port_no); 177 } 178 179 extern struct notifier_block ovs_dp_device_notifier; 180 extern struct genl_family dp_vport_genl_family; 181 extern struct genl_multicast_group ovs_dp_vport_multicast_group; 182 183 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *); 184 void ovs_dp_detach_port(struct vport *); 185 int ovs_dp_upcall(struct datapath *, struct sk_buff *, 186 const struct dp_upcall_info *); 187 188 const char *ovs_dp_name(const struct datapath *dp); 189 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq, 190 u8 cmd); 191 192 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb); 193 void ovs_dp_notify_wq(struct work_struct *work); 194 195 #define OVS_NLERR(fmt, ...) \ 196 pr_info_once("netlink: " fmt, ##__VA_ARGS__) 197 198 #endif /* datapath.h */ 199