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 #include <net/ip_tunnels.h> 29 30 #include "conntrack.h" 31 #include "flow.h" 32 #include "flow_table.h" 33 #include "meter.h" 34 #include "vport-internal_dev.h" 35 36 #define DP_MAX_PORTS USHRT_MAX 37 #define DP_VPORT_HASH_BUCKETS 1024 38 39 /** 40 * struct dp_stats_percpu - per-cpu packet processing statistics for a given 41 * datapath. 42 * @n_hit: Number of received packets for which a matching flow was found in 43 * the flow table. 44 * @n_miss: Number of received packets that had no matching flow in the flow 45 * table. The sum of @n_hit and @n_miss is the number of packets that have 46 * been received by the datapath. 47 * @n_lost: Number of received packets that had no matching flow in the flow 48 * table that could not be sent to userspace (normally due to an overflow in 49 * one of the datapath's queues). 50 * @n_mask_hit: Number of masks looked up for flow match. 51 * @n_mask_hit / (@n_hit + @n_missed) will be the average masks looked 52 * up per packet. 53 */ 54 struct dp_stats_percpu { 55 u64 n_hit; 56 u64 n_missed; 57 u64 n_lost; 58 u64 n_mask_hit; 59 struct u64_stats_sync syncp; 60 }; 61 62 /** 63 * struct datapath - datapath for flow-based packet switching 64 * @rcu: RCU callback head for deferred destruction. 65 * @list_node: Element in global 'dps' list. 66 * @table: flow table. 67 * @ports: Hash table for ports. %OVSP_LOCAL port always exists. Protected by 68 * ovs_mutex and RCU. 69 * @stats_percpu: Per-CPU datapath statistics. 70 * @net: Reference to net namespace. 71 * @max_headroom: the maximum headroom of all vports in this datapath; it will 72 * be used by all the internal vports in this dp. 73 * 74 * Context: See the comment on locking at the top of datapath.c for additional 75 * locking information. 76 */ 77 struct datapath { 78 struct rcu_head rcu; 79 struct list_head list_node; 80 81 /* Flow table. */ 82 struct flow_table table; 83 84 /* Switch ports. */ 85 struct hlist_head *ports; 86 87 /* Stats. */ 88 struct dp_stats_percpu __percpu *stats_percpu; 89 90 /* Network namespace ref. */ 91 possible_net_t net; 92 93 u32 user_features; 94 95 u32 max_headroom; 96 97 /* Switch meters. */ 98 struct hlist_head *meters; 99 }; 100 101 /** 102 * struct ovs_skb_cb - OVS data in skb CB 103 * @input_vport: The original vport packet came in on. This value is cached 104 * when a packet is received by OVS. 105 * @mru: The maximum received fragement size; 0 if the packet is not 106 * fragmented. 107 * @acts_origlen: The netlink size of the flow actions applied to this skb. 108 * @cutlen: The number of bytes from the packet end to be removed. 109 */ 110 struct ovs_skb_cb { 111 struct vport *input_vport; 112 u16 mru; 113 u16 acts_origlen; 114 u32 cutlen; 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 * @userdata: If nonnull, its variable-length value is passed to userspace as 122 * %OVS_PACKET_ATTR_USERDATA. 123 * @portid: Netlink portid to which packet should be sent. If @portid is 0 124 * then no packet is sent and the packet is accounted in the datapath's @n_lost 125 * counter. 126 * @egress_tun_info: If nonnull, becomes %OVS_PACKET_ATTR_EGRESS_TUN_KEY. 127 * @mru: If not zero, Maximum received IP fragment size. 128 */ 129 struct dp_upcall_info { 130 struct ip_tunnel_info *egress_tun_info; 131 const struct nlattr *userdata; 132 const struct nlattr *actions; 133 int actions_len; 134 u32 portid; 135 u8 cmd; 136 u16 mru; 137 }; 138 139 /** 140 * struct ovs_net - Per net-namespace data for ovs. 141 * @dps: List of datapaths to enable dumping them all out. 142 * Protected by genl_mutex. 143 */ 144 struct ovs_net { 145 struct list_head dps; 146 struct work_struct dp_notify_work; 147 148 /* Module reference for configuring conntrack. */ 149 bool xt_label; 150 }; 151 152 extern unsigned int ovs_net_id; 153 void ovs_lock(void); 154 void ovs_unlock(void); 155 156 #ifdef CONFIG_LOCKDEP 157 int lockdep_ovsl_is_held(void); 158 #else 159 #define lockdep_ovsl_is_held() 1 160 #endif 161 162 #define ASSERT_OVSL() WARN_ON(!lockdep_ovsl_is_held()) 163 #define ovsl_dereference(p) \ 164 rcu_dereference_protected(p, lockdep_ovsl_is_held()) 165 #define rcu_dereference_ovsl(p) \ 166 rcu_dereference_check(p, lockdep_ovsl_is_held()) 167 168 static inline struct net *ovs_dp_get_net(const struct datapath *dp) 169 { 170 return read_pnet(&dp->net); 171 } 172 173 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net) 174 { 175 write_pnet(&dp->net, net); 176 } 177 178 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no); 179 180 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no) 181 { 182 WARN_ON_ONCE(!rcu_read_lock_held()); 183 return ovs_lookup_vport(dp, port_no); 184 } 185 186 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no) 187 { 188 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); 189 return ovs_lookup_vport(dp, port_no); 190 } 191 192 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no) 193 { 194 ASSERT_OVSL(); 195 return ovs_lookup_vport(dp, port_no); 196 } 197 198 /* Must be called with rcu_read_lock. */ 199 static inline struct datapath *get_dp_rcu(struct net *net, int dp_ifindex) 200 { 201 struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex); 202 203 if (dev) { 204 struct vport *vport = ovs_internal_dev_get_vport(dev); 205 206 if (vport) 207 return vport->dp; 208 } 209 210 return NULL; 211 } 212 213 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the 214 * returned dp pointer valid. 215 */ 216 static inline struct datapath *get_dp(struct net *net, int dp_ifindex) 217 { 218 struct datapath *dp; 219 220 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held()); 221 rcu_read_lock(); 222 dp = get_dp_rcu(net, dp_ifindex); 223 rcu_read_unlock(); 224 225 return dp; 226 } 227 228 extern struct notifier_block ovs_dp_device_notifier; 229 extern struct genl_family dp_vport_genl_family; 230 231 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key); 232 void ovs_dp_detach_port(struct vport *); 233 int ovs_dp_upcall(struct datapath *, struct sk_buff *, 234 const struct sw_flow_key *, const struct dp_upcall_info *, 235 uint32_t cutlen); 236 237 const char *ovs_dp_name(const struct datapath *dp); 238 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, struct net *net, 239 u32 portid, u32 seq, u8 cmd); 240 241 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 242 const struct sw_flow_actions *, struct sw_flow_key *); 243 244 void ovs_dp_notify_wq(struct work_struct *work); 245 246 int action_fifos_init(void); 247 void action_fifos_exit(void); 248 249 /* 'KEY' must not have any bits set outside of the 'MASK' */ 250 #define OVS_MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK))) 251 #define OVS_SET_MASKED(OLD, KEY, MASK) ((OLD) = OVS_MASKED(OLD, KEY, MASK)) 252 253 #define OVS_NLERR(logging_allowed, fmt, ...) \ 254 do { \ 255 if (logging_allowed && net_ratelimit()) \ 256 pr_info("netlink: " fmt "\n", ##__VA_ARGS__); \ 257 } while (0) 258 #endif /* datapath.h */ 259