1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (c) 2007-2014 Nicira, Inc.
4 */
5
6 #ifndef DATAPATH_H
7 #define DATAPATH_H 1
8
9 #include <asm/page.h>
10 #include <linux/kernel.h>
11 #include <linux/mutex.h>
12 #include <linux/netdevice.h>
13 #include <linux/skbuff.h>
14 #include <linux/u64_stats_sync.h>
15 #include <net/ip_tunnels.h>
16
17 #include "conntrack.h"
18 #include "flow.h"
19 #include "flow_table.h"
20 #include "meter.h"
21 #include "vport-internal_dev.h"
22
23 #define DP_MAX_PORTS USHRT_MAX
24 #define DP_VPORT_HASH_BUCKETS 1024
25 #define DP_MASKS_REBALANCE_INTERVAL 4000
26
27 /**
28 * struct dp_stats_percpu - per-cpu packet processing statistics for a given
29 * datapath.
30 * @n_hit: Number of received packets for which a matching flow was found in
31 * the flow table.
32 * @n_miss: Number of received packets that had no matching flow in the flow
33 * table. The sum of @n_hit and @n_miss is the number of packets that have
34 * been received by the datapath.
35 * @n_lost: Number of received packets that had no matching flow in the flow
36 * table that could not be sent to userspace (normally due to an overflow in
37 * one of the datapath's queues).
38 * @n_mask_hit: Number of masks looked up for flow match.
39 * @n_mask_hit / (@n_hit + @n_missed) will be the average masks looked
40 * up per packet.
41 * @n_cache_hit: The number of received packets that had their mask found using
42 * the mask cache.
43 */
44 struct dp_stats_percpu {
45 u64 n_hit;
46 u64 n_missed;
47 u64 n_lost;
48 u64 n_mask_hit;
49 u64 n_cache_hit;
50 struct u64_stats_sync syncp;
51 };
52
53 /**
54 * struct datapath - datapath for flow-based packet switching
55 * @rcu: RCU callback head for deferred destruction.
56 * @list_node: Element in global 'dps' list.
57 * @table: flow table.
58 * @ports: Hash table for ports. %OVSP_LOCAL port always exists. Protected by
59 * ovs_mutex and RCU.
60 * @stats_percpu: Per-CPU datapath statistics.
61 * @net: Reference to net namespace.
62 * @max_headroom: the maximum headroom of all vports in this datapath; it will
63 * be used by all the internal vports in this dp.
64 *
65 * Context: See the comment on locking at the top of datapath.c for additional
66 * locking information.
67 */
68 struct datapath {
69 struct rcu_head rcu;
70 struct list_head list_node;
71
72 /* Flow table. */
73 struct flow_table table;
74
75 /* Switch ports. */
76 struct hlist_head *ports;
77
78 /* Stats. */
79 struct dp_stats_percpu __percpu *stats_percpu;
80
81 /* Network namespace ref. */
82 possible_net_t net;
83
84 u32 user_features;
85
86 u32 max_headroom;
87
88 /* Switch meters. */
89 struct dp_meter_table meter_tbl;
90 };
91
92 /**
93 * struct ovs_skb_cb - OVS data in skb CB
94 * @input_vport: The original vport packet came in on. This value is cached
95 * when a packet is received by OVS.
96 * @mru: The maximum received fragement size; 0 if the packet is not
97 * fragmented.
98 * @acts_origlen: The netlink size of the flow actions applied to this skb.
99 * @cutlen: The number of bytes from the packet end to be removed.
100 */
101 struct ovs_skb_cb {
102 struct vport *input_vport;
103 u16 mru;
104 u16 acts_origlen;
105 u32 cutlen;
106 };
107 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
108
109 /**
110 * struct dp_upcall - metadata to include with a packet to send to userspace
111 * @cmd: One of %OVS_PACKET_CMD_*.
112 * @userdata: If nonnull, its variable-length value is passed to userspace as
113 * %OVS_PACKET_ATTR_USERDATA.
114 * @portid: Netlink portid to which packet should be sent. If @portid is 0
115 * then no packet is sent and the packet is accounted in the datapath's @n_lost
116 * counter.
117 * @egress_tun_info: If nonnull, becomes %OVS_PACKET_ATTR_EGRESS_TUN_KEY.
118 * @mru: If not zero, Maximum received IP fragment size.
119 */
120 struct dp_upcall_info {
121 struct ip_tunnel_info *egress_tun_info;
122 const struct nlattr *userdata;
123 const struct nlattr *actions;
124 int actions_len;
125 u32 portid;
126 u8 cmd;
127 u16 mru;
128 };
129
130 /**
131 * struct ovs_net - Per net-namespace data for ovs.
132 * @dps: List of datapaths to enable dumping them all out.
133 * Protected by genl_mutex.
134 */
135 struct ovs_net {
136 struct list_head dps;
137 struct work_struct dp_notify_work;
138 struct delayed_work masks_rebalance;
139 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
140 struct ovs_ct_limit_info *ct_limit_info;
141 #endif
142
143 /* Module reference for configuring conntrack. */
144 bool xt_label;
145 };
146
147 /**
148 * enum ovs_pkt_hash_types - hash info to include with a packet
149 * to send to userspace.
150 * @OVS_PACKET_HASH_SW_BIT: indicates hash was computed in software stack.
151 * @OVS_PACKET_HASH_L4_BIT: indicates hash is a canonical 4-tuple hash
152 * over transport ports.
153 */
154 enum ovs_pkt_hash_types {
155 OVS_PACKET_HASH_SW_BIT = (1ULL << 32),
156 OVS_PACKET_HASH_L4_BIT = (1ULL << 33),
157 };
158
159 extern unsigned int ovs_net_id;
160 void ovs_lock(void);
161 void ovs_unlock(void);
162
163 #ifdef CONFIG_LOCKDEP
164 int lockdep_ovsl_is_held(void);
165 #else
166 #define lockdep_ovsl_is_held() 1
167 #endif
168
169 #define ASSERT_OVSL() WARN_ON(!lockdep_ovsl_is_held())
170 #define ovsl_dereference(p) \
171 rcu_dereference_protected(p, lockdep_ovsl_is_held())
172 #define rcu_dereference_ovsl(p) \
173 rcu_dereference_check(p, lockdep_ovsl_is_held())
174
ovs_dp_get_net(const struct datapath * dp)175 static inline struct net *ovs_dp_get_net(const struct datapath *dp)
176 {
177 return read_pnet(&dp->net);
178 }
179
ovs_dp_set_net(struct datapath * dp,struct net * net)180 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net)
181 {
182 write_pnet(&dp->net, net);
183 }
184
185 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no);
186
ovs_vport_rcu(const struct datapath * dp,int port_no)187 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no)
188 {
189 WARN_ON_ONCE(!rcu_read_lock_held());
190 return ovs_lookup_vport(dp, port_no);
191 }
192
ovs_vport_ovsl_rcu(const struct datapath * dp,int port_no)193 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no)
194 {
195 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
196 return ovs_lookup_vport(dp, port_no);
197 }
198
ovs_vport_ovsl(const struct datapath * dp,int port_no)199 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no)
200 {
201 ASSERT_OVSL();
202 return ovs_lookup_vport(dp, port_no);
203 }
204
205 /* Must be called with rcu_read_lock. */
get_dp_rcu(struct net * net,int dp_ifindex)206 static inline struct datapath *get_dp_rcu(struct net *net, int dp_ifindex)
207 {
208 struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex);
209
210 if (dev) {
211 struct vport *vport = ovs_internal_dev_get_vport(dev);
212
213 if (vport)
214 return vport->dp;
215 }
216
217 return NULL;
218 }
219
220 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the
221 * returned dp pointer valid.
222 */
get_dp(struct net * net,int dp_ifindex)223 static inline struct datapath *get_dp(struct net *net, int dp_ifindex)
224 {
225 struct datapath *dp;
226
227 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
228 rcu_read_lock();
229 dp = get_dp_rcu(net, dp_ifindex);
230 rcu_read_unlock();
231
232 return dp;
233 }
234
235 extern struct notifier_block ovs_dp_device_notifier;
236 extern struct genl_family dp_vport_genl_family;
237
238 DECLARE_STATIC_KEY_FALSE(tc_recirc_sharing_support);
239
240 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key);
241 void ovs_dp_detach_port(struct vport *);
242 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
243 const struct sw_flow_key *, const struct dp_upcall_info *,
244 uint32_t cutlen);
245
246 const char *ovs_dp_name(const struct datapath *dp);
247 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, struct net *net,
248 u32 portid, u32 seq, u8 cmd);
249
250 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
251 const struct sw_flow_actions *, struct sw_flow_key *);
252
253 void ovs_dp_notify_wq(struct work_struct *work);
254
255 int action_fifos_init(void);
256 void action_fifos_exit(void);
257
258 /* 'KEY' must not have any bits set outside of the 'MASK' */
259 #define OVS_MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK)))
260 #define OVS_SET_MASKED(OLD, KEY, MASK) ((OLD) = OVS_MASKED(OLD, KEY, MASK))
261
262 #define OVS_NLERR(logging_allowed, fmt, ...) \
263 do { \
264 if (logging_allowed && net_ratelimit()) \
265 pr_info("netlink: " fmt "\n", ##__VA_ARGS__); \
266 } while (0)
267 #endif /* datapath.h */
268