1 /* 2 * Copyright (c) 2007-2014 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 syncp; 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 /* Network namespace ref. */ 88 possible_net_t net; 89 90 u32 user_features; 91 }; 92 93 /** 94 * struct ovs_skb_cb - OVS data in skb CB 95 * @egress_tun_key: Tunnel information about this packet on egress path. 96 * NULL if the packet is not being tunneled. 97 * @input_vport: The original vport packet came in on. This value is cached 98 * when a packet is received by OVS. 99 */ 100 struct ovs_skb_cb { 101 struct ovs_tunnel_info *egress_tun_info; 102 struct vport *input_vport; 103 }; 104 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) 105 106 /** 107 * struct dp_upcall - metadata to include with a packet to send to userspace 108 * @cmd: One of %OVS_PACKET_CMD_*. 109 * @userdata: If nonnull, its variable-length value is passed to userspace as 110 * %OVS_PACKET_ATTR_USERDATA. 111 * @portid: Netlink portid to which packet should be sent. If @portid is 0 112 * then no packet is sent and the packet is accounted in the datapath's @n_lost 113 * counter. 114 * @egress_tun_info: If nonnull, becomes %OVS_PACKET_ATTR_EGRESS_TUN_KEY. 115 */ 116 struct dp_upcall_info { 117 const struct ovs_tunnel_info *egress_tun_info; 118 const struct nlattr *userdata; 119 const struct nlattr *actions; 120 int actions_len; 121 u32 portid; 122 u8 cmd; 123 }; 124 125 /** 126 * struct ovs_net - Per net-namespace data for ovs. 127 * @dps: List of datapaths to enable dumping them all out. 128 * Protected by genl_mutex. 129 */ 130 struct ovs_net { 131 struct list_head dps; 132 struct work_struct dp_notify_work; 133 struct vport_net vport_net; 134 }; 135 136 extern int ovs_net_id; 137 void ovs_lock(void); 138 void ovs_unlock(void); 139 140 #ifdef CONFIG_LOCKDEP 141 int lockdep_ovsl_is_held(void); 142 #else 143 #define lockdep_ovsl_is_held() 1 144 #endif 145 146 #define ASSERT_OVSL() WARN_ON(!lockdep_ovsl_is_held()) 147 #define ovsl_dereference(p) \ 148 rcu_dereference_protected(p, lockdep_ovsl_is_held()) 149 #define rcu_dereference_ovsl(p) \ 150 rcu_dereference_check(p, lockdep_ovsl_is_held()) 151 152 static inline struct net *ovs_dp_get_net(const struct datapath *dp) 153 { 154 return read_pnet(&dp->net); 155 } 156 157 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) 158 { 159 write_pnet(&dp->net, net); 160 } 161 162 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); 163 164 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) 165 { 166 WARN_ON_ONCE(!rcu_read_lock_held()); 167 return ovs_lookup_vport(dp, port_no); 168 } 169 170 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no) 171 { 172 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); 173 return ovs_lookup_vport(dp, port_no); 174 } 175 176 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no) 177 { 178 ASSERT_OVSL(); 179 return ovs_lookup_vport(dp, port_no); 180 } 181 182 extern struct notifier_block ovs_dp_device_notifier; 183 extern struct genl_family dp_vport_genl_family; 184 185 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key); 186 void ovs_dp_detach_port(struct vport *); 187 int ovs_dp_upcall(struct datapath *, struct sk_buff *, 188 const struct sw_flow_key *, const struct dp_upcall_info *); 189 190 const char *ovs_dp_name(const struct datapath *dp); 191 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq, 192 u8 cmd); 193 194 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 195 const struct sw_flow_actions *, struct sw_flow_key *); 196 197 void ovs_dp_notify_wq(struct work_struct *work); 198 199 int action_fifos_init(void); 200 void action_fifos_exit(void); 201 202 #define OVS_NLERR(logging_allowed, fmt, ...) \ 203 do { \ 204 if (logging_allowed && net_ratelimit()) \ 205 pr_info("netlink: " fmt "\n", ##__VA_ARGS__); \ 206 } while (0) 207 #endif /* datapath.h */ 208