xref: /openbmc/linux/include/net/l3mdev.h (revision feac8c8b)
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 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
105 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
106 static inline u32 l3mdev_fib_table(const struct net_device *dev)
107 {
108 	u32 tb_id;
109 
110 	rcu_read_lock();
111 	tb_id = l3mdev_fib_table_rcu(dev);
112 	rcu_read_unlock();
113 
114 	return tb_id;
115 }
116 
117 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
118 {
119 	struct net_device *dev;
120 	bool rc = false;
121 
122 	if (ifindex == 0)
123 		return false;
124 
125 	rcu_read_lock();
126 
127 	dev = dev_get_by_index_rcu(net, ifindex);
128 	if (dev)
129 		rc = netif_is_l3_master(dev);
130 
131 	rcu_read_unlock();
132 
133 	return rc;
134 }
135 
136 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
137 
138 static inline
139 struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
140 {
141 	struct net_device *master = NULL;
142 
143 	if (netif_is_l3_slave(skb->dev))
144 		master = netdev_master_upper_dev_get_rcu(skb->dev);
145 	else if (netif_is_l3_master(skb->dev))
146 		master = skb->dev;
147 
148 	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
149 		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
150 
151 	return skb;
152 }
153 
154 static inline
155 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
156 {
157 	return l3mdev_l3_rcv(skb, AF_INET);
158 }
159 
160 static inline
161 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
162 {
163 	return l3mdev_l3_rcv(skb, AF_INET6);
164 }
165 
166 static inline
167 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
168 {
169 	struct net_device *dev = skb_dst(skb)->dev;
170 
171 	if (netif_is_l3_slave(dev)) {
172 		struct net_device *master;
173 
174 		master = netdev_master_upper_dev_get_rcu(dev);
175 		if (master && master->l3mdev_ops->l3mdev_l3_out)
176 			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
177 								skb, proto);
178 	}
179 
180 	return skb;
181 }
182 
183 static inline
184 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
185 {
186 	return l3mdev_l3_out(sk, skb, AF_INET);
187 }
188 
189 static inline
190 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
191 {
192 	return l3mdev_l3_out(sk, skb, AF_INET6);
193 }
194 #else
195 
196 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
197 {
198 	return 0;
199 }
200 static inline int l3mdev_master_ifindex(struct net_device *dev)
201 {
202 	return 0;
203 }
204 
205 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
206 {
207 	return 0;
208 }
209 
210 static inline
211 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
212 {
213 	return NULL;
214 }
215 
216 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
217 {
218 	return 0;
219 }
220 static inline u32 l3mdev_fib_table(const struct net_device *dev)
221 {
222 	return 0;
223 }
224 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
225 {
226 	return 0;
227 }
228 
229 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
230 {
231 	return false;
232 }
233 
234 static inline
235 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
236 {
237 	return NULL;
238 }
239 
240 static inline
241 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
242 {
243 	return skb;
244 }
245 
246 static inline
247 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
248 {
249 	return skb;
250 }
251 
252 static inline
253 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
254 {
255 	return skb;
256 }
257 
258 static inline
259 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
260 {
261 	return skb;
262 }
263 
264 static inline
265 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
266 			  struct fib_lookup_arg *arg)
267 {
268 	return 1;
269 }
270 static inline
271 void l3mdev_update_flow(struct net *net, struct flowi *fl)
272 {
273 }
274 #endif
275 
276 #endif /* _NET_L3MDEV_H_ */
277