xref: /openbmc/linux/include/net/l3mdev.h (revision d003d772)
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 		 netif_has_l3_rx_handler(skb->dev))
158 		master = skb->dev;
159 
160 	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
161 		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
162 
163 	return skb;
164 }
165 
166 static inline
167 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
168 {
169 	return l3mdev_l3_rcv(skb, AF_INET);
170 }
171 
172 static inline
173 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
174 {
175 	return l3mdev_l3_rcv(skb, AF_INET6);
176 }
177 
178 static inline
179 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
180 {
181 	struct net_device *dev = skb_dst(skb)->dev;
182 
183 	if (netif_is_l3_slave(dev)) {
184 		struct net_device *master;
185 
186 		master = netdev_master_upper_dev_get_rcu(dev);
187 		if (master && master->l3mdev_ops->l3mdev_l3_out)
188 			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
189 								skb, proto);
190 	}
191 
192 	return skb;
193 }
194 
195 static inline
196 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
197 {
198 	return l3mdev_l3_out(sk, skb, AF_INET);
199 }
200 
201 static inline
202 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
203 {
204 	return l3mdev_l3_out(sk, skb, AF_INET6);
205 }
206 #else
207 
208 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
209 {
210 	return 0;
211 }
212 static inline int l3mdev_master_ifindex(struct net_device *dev)
213 {
214 	return 0;
215 }
216 
217 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
218 {
219 	return 0;
220 }
221 
222 static inline
223 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
224 {
225 	return 0;
226 }
227 static inline
228 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
229 {
230 	return 0;
231 }
232 
233 static inline
234 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
235 {
236 	return NULL;
237 }
238 
239 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
240 {
241 	return 0;
242 }
243 static inline u32 l3mdev_fib_table(const struct net_device *dev)
244 {
245 	return 0;
246 }
247 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
248 {
249 	return 0;
250 }
251 
252 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
253 {
254 	return false;
255 }
256 
257 static inline
258 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
259 {
260 	return NULL;
261 }
262 
263 static inline
264 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
265 {
266 	return skb;
267 }
268 
269 static inline
270 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
271 {
272 	return skb;
273 }
274 
275 static inline
276 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
277 {
278 	return skb;
279 }
280 
281 static inline
282 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
283 {
284 	return skb;
285 }
286 
287 static inline
288 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
289 			  struct fib_lookup_arg *arg)
290 {
291 	return 1;
292 }
293 static inline
294 void l3mdev_update_flow(struct net *net, struct flowi *fl)
295 {
296 }
297 #endif
298 
299 #endif /* _NET_L3MDEV_H_ */
300