xref: /openbmc/linux/include/net/l3mdev.h (revision 5e012745)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * include/net/l3mdev.h - L3 master device API
4  * Copyright (c) 2015 Cumulus Networks
5  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
6  */
7 #ifndef _NET_L3MDEV_H_
8 #define _NET_L3MDEV_H_
9 
10 #include <net/dst.h>
11 #include <net/fib_rules.h>
12 
13 /**
14  * struct l3mdev_ops - l3mdev operations
15  *
16  * @l3mdev_fib_table: Get FIB table id to use for lookups
17  *
18  * @l3mdev_l3_rcv:    Hook in L3 receive path
19  *
20  * @l3mdev_l3_out:    Hook in L3 output path
21  *
22  * @l3mdev_link_scope_lookup: IPv6 lookup for linklocal and mcast destinations
23  */
24 
25 struct l3mdev_ops {
26 	u32		(*l3mdev_fib_table)(const struct net_device *dev);
27 	struct sk_buff * (*l3mdev_l3_rcv)(struct net_device *dev,
28 					  struct sk_buff *skb, u16 proto);
29 	struct sk_buff * (*l3mdev_l3_out)(struct net_device *dev,
30 					  struct sock *sk, struct sk_buff *skb,
31 					  u16 proto);
32 
33 	/* IPv6 ops */
34 	struct dst_entry * (*l3mdev_link_scope_lookup)(const struct net_device *dev,
35 						 struct flowi6 *fl6);
36 };
37 
38 #ifdef CONFIG_NET_L3_MASTER_DEV
39 
40 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
41 			  struct fib_lookup_arg *arg);
42 
43 void l3mdev_update_flow(struct net *net, struct flowi *fl);
44 
45 int l3mdev_master_ifindex_rcu(const struct net_device *dev);
46 static inline int l3mdev_master_ifindex(struct net_device *dev)
47 {
48 	int ifindex;
49 
50 	rcu_read_lock();
51 	ifindex = l3mdev_master_ifindex_rcu(dev);
52 	rcu_read_unlock();
53 
54 	return ifindex;
55 }
56 
57 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
58 {
59 	struct net_device *dev;
60 	int rc = 0;
61 
62 	if (likely(ifindex)) {
63 		rcu_read_lock();
64 
65 		dev = dev_get_by_index_rcu(net, ifindex);
66 		if (dev)
67 			rc = l3mdev_master_ifindex_rcu(dev);
68 
69 		rcu_read_unlock();
70 	}
71 
72 	return rc;
73 }
74 
75 static inline
76 struct net_device *l3mdev_master_dev_rcu(const struct net_device *_dev)
77 {
78 	/* netdev_master_upper_dev_get_rcu calls
79 	 * list_first_or_null_rcu to walk the upper dev list.
80 	 * list_first_or_null_rcu does not handle a const arg. We aren't
81 	 * making changes, just want the master device from that list so
82 	 * typecast to remove the const
83 	 */
84 	struct net_device *dev = (struct net_device *)_dev;
85 	struct net_device *master;
86 
87 	if (!dev)
88 		return NULL;
89 
90 	if (netif_is_l3_master(dev))
91 		master = dev;
92 	else if (netif_is_l3_slave(dev))
93 		master = netdev_master_upper_dev_get_rcu(dev);
94 	else
95 		master = NULL;
96 
97 	return master;
98 }
99 
100 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
101 static inline
102 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
103 {
104 	rcu_read_lock();
105 	ifindex = l3mdev_master_upper_ifindex_by_index_rcu(net, ifindex);
106 	rcu_read_unlock();
107 
108 	return ifindex;
109 }
110 
111 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
112 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
113 static inline u32 l3mdev_fib_table(const struct net_device *dev)
114 {
115 	u32 tb_id;
116 
117 	rcu_read_lock();
118 	tb_id = l3mdev_fib_table_rcu(dev);
119 	rcu_read_unlock();
120 
121 	return tb_id;
122 }
123 
124 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
125 {
126 	struct net_device *dev;
127 	bool rc = false;
128 
129 	if (ifindex == 0)
130 		return false;
131 
132 	rcu_read_lock();
133 
134 	dev = dev_get_by_index_rcu(net, ifindex);
135 	if (dev)
136 		rc = netif_is_l3_master(dev);
137 
138 	rcu_read_unlock();
139 
140 	return rc;
141 }
142 
143 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
144 
145 static inline
146 struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
147 {
148 	struct net_device *master = NULL;
149 
150 	if (netif_is_l3_slave(skb->dev))
151 		master = netdev_master_upper_dev_get_rcu(skb->dev);
152 	else if (netif_is_l3_master(skb->dev) ||
153 		 netif_has_l3_rx_handler(skb->dev))
154 		master = skb->dev;
155 
156 	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
157 		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
158 
159 	return skb;
160 }
161 
162 static inline
163 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
164 {
165 	return l3mdev_l3_rcv(skb, AF_INET);
166 }
167 
168 static inline
169 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
170 {
171 	return l3mdev_l3_rcv(skb, AF_INET6);
172 }
173 
174 static inline
175 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
176 {
177 	struct net_device *dev = skb_dst(skb)->dev;
178 
179 	if (netif_is_l3_slave(dev)) {
180 		struct net_device *master;
181 
182 		master = netdev_master_upper_dev_get_rcu(dev);
183 		if (master && master->l3mdev_ops->l3mdev_l3_out)
184 			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
185 								skb, proto);
186 	}
187 
188 	return skb;
189 }
190 
191 static inline
192 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
193 {
194 	return l3mdev_l3_out(sk, skb, AF_INET);
195 }
196 
197 static inline
198 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
199 {
200 	return l3mdev_l3_out(sk, skb, AF_INET6);
201 }
202 #else
203 
204 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
205 {
206 	return 0;
207 }
208 static inline int l3mdev_master_ifindex(struct net_device *dev)
209 {
210 	return 0;
211 }
212 
213 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
214 {
215 	return 0;
216 }
217 
218 static inline
219 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
220 {
221 	return 0;
222 }
223 static inline
224 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
225 {
226 	return 0;
227 }
228 
229 static inline
230 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
231 {
232 	return NULL;
233 }
234 
235 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
236 {
237 	return 0;
238 }
239 static inline u32 l3mdev_fib_table(const struct net_device *dev)
240 {
241 	return 0;
242 }
243 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
244 {
245 	return 0;
246 }
247 
248 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
249 {
250 	return false;
251 }
252 
253 static inline
254 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
255 {
256 	return NULL;
257 }
258 
259 static inline
260 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
261 {
262 	return skb;
263 }
264 
265 static inline
266 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
267 {
268 	return skb;
269 }
270 
271 static inline
272 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
273 {
274 	return skb;
275 }
276 
277 static inline
278 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
279 {
280 	return skb;
281 }
282 
283 static inline
284 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
285 			  struct fib_lookup_arg *arg)
286 {
287 	return 1;
288 }
289 static inline
290 void l3mdev_update_flow(struct net *net, struct flowi *fl)
291 {
292 }
293 #endif
294 
295 #endif /* _NET_L3MDEV_H_ */
296