xref: /openbmc/linux/include/net/l3mdev.h (revision df687341)
1 /*
2  * include/net/l3mdev.h - L3 master device API
3  * Copyright (c) 2015 Cumulus Networks
4  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 #ifndef _NET_L3MDEV_H_
12 #define _NET_L3MDEV_H_
13 
14 #include <net/dst.h>
15 #include <net/fib_rules.h>
16 
17 /**
18  * struct l3mdev_ops - l3mdev operations
19  *
20  * @l3mdev_fib_table: Get FIB table id to use for lookups
21  *
22  * @l3mdev_l3_rcv:    Hook in L3 receive path
23  *
24  * @l3mdev_l3_out:    Hook in L3 output path
25  *
26  * @l3mdev_link_scope_lookup: IPv6 lookup for linklocal and mcast destinations
27  */
28 
29 struct l3mdev_ops {
30 	u32		(*l3mdev_fib_table)(const struct net_device *dev);
31 	struct sk_buff * (*l3mdev_l3_rcv)(struct net_device *dev,
32 					  struct sk_buff *skb, u16 proto);
33 	struct sk_buff * (*l3mdev_l3_out)(struct net_device *dev,
34 					  struct sock *sk, struct sk_buff *skb,
35 					  u16 proto);
36 
37 	/* IPv6 ops */
38 	struct dst_entry * (*l3mdev_link_scope_lookup)(const struct net_device *dev,
39 						 struct flowi6 *fl6);
40 };
41 
42 #ifdef CONFIG_NET_L3_MASTER_DEV
43 
44 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
45 			  struct fib_lookup_arg *arg);
46 
47 void l3mdev_update_flow(struct net *net, struct flowi *fl);
48 
49 int l3mdev_master_ifindex_rcu(const struct net_device *dev);
50 static inline int l3mdev_master_ifindex(struct net_device *dev)
51 {
52 	int ifindex;
53 
54 	rcu_read_lock();
55 	ifindex = l3mdev_master_ifindex_rcu(dev);
56 	rcu_read_unlock();
57 
58 	return ifindex;
59 }
60 
61 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
62 {
63 	struct net_device *dev;
64 	int rc = 0;
65 
66 	if (likely(ifindex)) {
67 		rcu_read_lock();
68 
69 		dev = dev_get_by_index_rcu(net, ifindex);
70 		if (dev)
71 			rc = l3mdev_master_ifindex_rcu(dev);
72 
73 		rcu_read_unlock();
74 	}
75 
76 	return rc;
77 }
78 
79 static inline
80 struct net_device *l3mdev_master_dev_rcu(const struct net_device *_dev)
81 {
82 	/* netdev_master_upper_dev_get_rcu calls
83 	 * list_first_or_null_rcu to walk the upper dev list.
84 	 * list_first_or_null_rcu does not handle a const arg. We aren't
85 	 * making changes, just want the master device from that list so
86 	 * typecast to remove the const
87 	 */
88 	struct net_device *dev = (struct net_device *)_dev;
89 	struct net_device *master;
90 
91 	if (!dev)
92 		return NULL;
93 
94 	if (netif_is_l3_master(dev))
95 		master = dev;
96 	else if (netif_is_l3_slave(dev))
97 		master = netdev_master_upper_dev_get_rcu(dev);
98 	else
99 		master = NULL;
100 
101 	return master;
102 }
103 
104 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
105 static inline
106 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
107 {
108 	rcu_read_lock();
109 	ifindex = l3mdev_master_upper_ifindex_by_index_rcu(net, ifindex);
110 	rcu_read_unlock();
111 
112 	return ifindex;
113 }
114 
115 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
116 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
117 static inline u32 l3mdev_fib_table(const struct net_device *dev)
118 {
119 	u32 tb_id;
120 
121 	rcu_read_lock();
122 	tb_id = l3mdev_fib_table_rcu(dev);
123 	rcu_read_unlock();
124 
125 	return tb_id;
126 }
127 
128 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
129 {
130 	struct net_device *dev;
131 	bool rc = false;
132 
133 	if (ifindex == 0)
134 		return false;
135 
136 	rcu_read_lock();
137 
138 	dev = dev_get_by_index_rcu(net, ifindex);
139 	if (dev)
140 		rc = netif_is_l3_master(dev);
141 
142 	rcu_read_unlock();
143 
144 	return rc;
145 }
146 
147 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
148 
149 static inline
150 struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
151 {
152 	struct net_device *master = NULL;
153 
154 	if (netif_is_l3_slave(skb->dev))
155 		master = netdev_master_upper_dev_get_rcu(skb->dev);
156 	else if (netif_is_l3_master(skb->dev))
157 		master = skb->dev;
158 
159 	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
160 		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
161 
162 	return skb;
163 }
164 
165 static inline
166 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
167 {
168 	return l3mdev_l3_rcv(skb, AF_INET);
169 }
170 
171 static inline
172 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
173 {
174 	return l3mdev_l3_rcv(skb, AF_INET6);
175 }
176 
177 static inline
178 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
179 {
180 	struct net_device *dev = skb_dst(skb)->dev;
181 
182 	if (netif_is_l3_slave(dev)) {
183 		struct net_device *master;
184 
185 		master = netdev_master_upper_dev_get_rcu(dev);
186 		if (master && master->l3mdev_ops->l3mdev_l3_out)
187 			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
188 								skb, proto);
189 	}
190 
191 	return skb;
192 }
193 
194 static inline
195 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
196 {
197 	return l3mdev_l3_out(sk, skb, AF_INET);
198 }
199 
200 static inline
201 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
202 {
203 	return l3mdev_l3_out(sk, skb, AF_INET6);
204 }
205 #else
206 
207 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
208 {
209 	return 0;
210 }
211 static inline int l3mdev_master_ifindex(struct net_device *dev)
212 {
213 	return 0;
214 }
215 
216 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
217 {
218 	return 0;
219 }
220 
221 static inline
222 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
223 {
224 	return 0;
225 }
226 static inline
227 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
228 {
229 	return 0;
230 }
231 
232 static inline
233 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
234 {
235 	return NULL;
236 }
237 
238 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
239 {
240 	return 0;
241 }
242 static inline u32 l3mdev_fib_table(const struct net_device *dev)
243 {
244 	return 0;
245 }
246 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
247 {
248 	return 0;
249 }
250 
251 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
252 {
253 	return false;
254 }
255 
256 static inline
257 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
258 {
259 	return NULL;
260 }
261 
262 static inline
263 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
264 {
265 	return skb;
266 }
267 
268 static inline
269 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
270 {
271 	return skb;
272 }
273 
274 static inline
275 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
276 {
277 	return skb;
278 }
279 
280 static inline
281 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
282 {
283 	return skb;
284 }
285 
286 static inline
287 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
288 			  struct fib_lookup_arg *arg)
289 {
290 	return 1;
291 }
292 static inline
293 void l3mdev_update_flow(struct net *net, struct flowi *fl)
294 {
295 }
296 #endif
297 
298 #endif /* _NET_L3MDEV_H_ */
299