xref: /openbmc/linux/net/switchdev/switchdev.c (revision e6c81cce)
1 /*
2  * net/switchdev/switchdev.c - Switch device API
3  * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
4  * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.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 
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/init.h>
15 #include <linux/mutex.h>
16 #include <linux/notifier.h>
17 #include <linux/netdevice.h>
18 #include <net/ip_fib.h>
19 #include <net/switchdev.h>
20 
21 /**
22  *	netdev_switch_parent_id_get - Get ID of a switch
23  *	@dev: port device
24  *	@psid: switch ID
25  *
26  *	Get ID of a switch this port is part of.
27  */
28 int netdev_switch_parent_id_get(struct net_device *dev,
29 				struct netdev_phys_item_id *psid)
30 {
31 	const struct swdev_ops *ops = dev->swdev_ops;
32 
33 	if (!ops || !ops->swdev_parent_id_get)
34 		return -EOPNOTSUPP;
35 	return ops->swdev_parent_id_get(dev, psid);
36 }
37 EXPORT_SYMBOL_GPL(netdev_switch_parent_id_get);
38 
39 /**
40  *	netdev_switch_port_stp_update - Notify switch device port of STP
41  *					state change
42  *	@dev: port device
43  *	@state: port STP state
44  *
45  *	Notify switch device port of bridge port STP state change.
46  */
47 int netdev_switch_port_stp_update(struct net_device *dev, u8 state)
48 {
49 	const struct swdev_ops *ops = dev->swdev_ops;
50 	struct net_device *lower_dev;
51 	struct list_head *iter;
52 	int err = -EOPNOTSUPP;
53 
54 	if (ops && ops->swdev_port_stp_update)
55 		return ops->swdev_port_stp_update(dev, state);
56 
57 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
58 		err = netdev_switch_port_stp_update(lower_dev, state);
59 		if (err && err != -EOPNOTSUPP)
60 			return err;
61 	}
62 
63 	return err;
64 }
65 EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
66 
67 static DEFINE_MUTEX(netdev_switch_mutex);
68 static RAW_NOTIFIER_HEAD(netdev_switch_notif_chain);
69 
70 /**
71  *	register_netdev_switch_notifier - Register notifier
72  *	@nb: notifier_block
73  *
74  *	Register switch device notifier. This should be used by code
75  *	which needs to monitor events happening in particular device.
76  *	Return values are same as for atomic_notifier_chain_register().
77  */
78 int register_netdev_switch_notifier(struct notifier_block *nb)
79 {
80 	int err;
81 
82 	mutex_lock(&netdev_switch_mutex);
83 	err = raw_notifier_chain_register(&netdev_switch_notif_chain, nb);
84 	mutex_unlock(&netdev_switch_mutex);
85 	return err;
86 }
87 EXPORT_SYMBOL_GPL(register_netdev_switch_notifier);
88 
89 /**
90  *	unregister_netdev_switch_notifier - Unregister notifier
91  *	@nb: notifier_block
92  *
93  *	Unregister switch device notifier.
94  *	Return values are same as for atomic_notifier_chain_unregister().
95  */
96 int unregister_netdev_switch_notifier(struct notifier_block *nb)
97 {
98 	int err;
99 
100 	mutex_lock(&netdev_switch_mutex);
101 	err = raw_notifier_chain_unregister(&netdev_switch_notif_chain, nb);
102 	mutex_unlock(&netdev_switch_mutex);
103 	return err;
104 }
105 EXPORT_SYMBOL_GPL(unregister_netdev_switch_notifier);
106 
107 /**
108  *	call_netdev_switch_notifiers - Call notifiers
109  *	@val: value passed unmodified to notifier function
110  *	@dev: port device
111  *	@info: notifier information data
112  *
113  *	Call all network notifier blocks. This should be called by driver
114  *	when it needs to propagate hardware event.
115  *	Return values are same as for atomic_notifier_call_chain().
116  */
117 int call_netdev_switch_notifiers(unsigned long val, struct net_device *dev,
118 				 struct netdev_switch_notifier_info *info)
119 {
120 	int err;
121 
122 	info->dev = dev;
123 	mutex_lock(&netdev_switch_mutex);
124 	err = raw_notifier_call_chain(&netdev_switch_notif_chain, val, info);
125 	mutex_unlock(&netdev_switch_mutex);
126 	return err;
127 }
128 EXPORT_SYMBOL_GPL(call_netdev_switch_notifiers);
129 
130 /**
131  *	netdev_switch_port_bridge_setlink - Notify switch device port of bridge
132  *	port attributes
133  *
134  *	@dev: port device
135  *	@nlh: netlink msg with bridge port attributes
136  *	@flags: bridge setlink flags
137  *
138  *	Notify switch device port of bridge port attributes
139  */
140 int netdev_switch_port_bridge_setlink(struct net_device *dev,
141 				      struct nlmsghdr *nlh, u16 flags)
142 {
143 	const struct net_device_ops *ops = dev->netdev_ops;
144 
145 	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
146 		return 0;
147 
148 	if (!ops->ndo_bridge_setlink)
149 		return -EOPNOTSUPP;
150 
151 	return ops->ndo_bridge_setlink(dev, nlh, flags);
152 }
153 EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_setlink);
154 
155 /**
156  *	netdev_switch_port_bridge_dellink - Notify switch device port of bridge
157  *	port attribute delete
158  *
159  *	@dev: port device
160  *	@nlh: netlink msg with bridge port attributes
161  *	@flags: bridge setlink flags
162  *
163  *	Notify switch device port of bridge port attribute delete
164  */
165 int netdev_switch_port_bridge_dellink(struct net_device *dev,
166 				      struct nlmsghdr *nlh, u16 flags)
167 {
168 	const struct net_device_ops *ops = dev->netdev_ops;
169 
170 	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
171 		return 0;
172 
173 	if (!ops->ndo_bridge_dellink)
174 		return -EOPNOTSUPP;
175 
176 	return ops->ndo_bridge_dellink(dev, nlh, flags);
177 }
178 EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_dellink);
179 
180 /**
181  *	ndo_dflt_netdev_switch_port_bridge_setlink - default ndo bridge setlink
182  *						     op for master devices
183  *
184  *	@dev: port device
185  *	@nlh: netlink msg with bridge port attributes
186  *	@flags: bridge setlink flags
187  *
188  *	Notify master device slaves of bridge port attributes
189  */
190 int ndo_dflt_netdev_switch_port_bridge_setlink(struct net_device *dev,
191 					       struct nlmsghdr *nlh, u16 flags)
192 {
193 	struct net_device *lower_dev;
194 	struct list_head *iter;
195 	int ret = 0, err = 0;
196 
197 	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
198 		return ret;
199 
200 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
201 		err = netdev_switch_port_bridge_setlink(lower_dev, nlh, flags);
202 		if (err && err != -EOPNOTSUPP)
203 			ret = err;
204 	}
205 
206 	return ret;
207 }
208 EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_setlink);
209 
210 /**
211  *	ndo_dflt_netdev_switch_port_bridge_dellink - default ndo bridge dellink
212  *						     op for master devices
213  *
214  *	@dev: port device
215  *	@nlh: netlink msg with bridge port attributes
216  *	@flags: bridge dellink flags
217  *
218  *	Notify master device slaves of bridge port attribute deletes
219  */
220 int ndo_dflt_netdev_switch_port_bridge_dellink(struct net_device *dev,
221 					       struct nlmsghdr *nlh, u16 flags)
222 {
223 	struct net_device *lower_dev;
224 	struct list_head *iter;
225 	int ret = 0, err = 0;
226 
227 	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
228 		return ret;
229 
230 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
231 		err = netdev_switch_port_bridge_dellink(lower_dev, nlh, flags);
232 		if (err && err != -EOPNOTSUPP)
233 			ret = err;
234 	}
235 
236 	return ret;
237 }
238 EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_dellink);
239 
240 static struct net_device *netdev_switch_get_lowest_dev(struct net_device *dev)
241 {
242 	const struct swdev_ops *ops = dev->swdev_ops;
243 	struct net_device *lower_dev;
244 	struct net_device *port_dev;
245 	struct list_head *iter;
246 
247 	/* Recusively search down until we find a sw port dev.
248 	 * (A sw port dev supports swdev_parent_id_get).
249 	 */
250 
251 	if (dev->features & NETIF_F_HW_SWITCH_OFFLOAD &&
252 	    ops && ops->swdev_parent_id_get)
253 		return dev;
254 
255 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
256 		port_dev = netdev_switch_get_lowest_dev(lower_dev);
257 		if (port_dev)
258 			return port_dev;
259 	}
260 
261 	return NULL;
262 }
263 
264 static struct net_device *netdev_switch_get_dev_by_nhs(struct fib_info *fi)
265 {
266 	struct netdev_phys_item_id psid;
267 	struct netdev_phys_item_id prev_psid;
268 	struct net_device *dev = NULL;
269 	int nhsel;
270 
271 	/* For this route, all nexthop devs must be on the same switch. */
272 
273 	for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
274 		const struct fib_nh *nh = &fi->fib_nh[nhsel];
275 
276 		if (!nh->nh_dev)
277 			return NULL;
278 
279 		dev = netdev_switch_get_lowest_dev(nh->nh_dev);
280 		if (!dev)
281 			return NULL;
282 
283 		if (netdev_switch_parent_id_get(dev, &psid))
284 			return NULL;
285 
286 		if (nhsel > 0) {
287 			if (prev_psid.id_len != psid.id_len)
288 				return NULL;
289 			if (memcmp(prev_psid.id, psid.id, psid.id_len))
290 				return NULL;
291 		}
292 
293 		prev_psid = psid;
294 	}
295 
296 	return dev;
297 }
298 
299 /**
300  *	netdev_switch_fib_ipv4_add - Add IPv4 route entry to switch
301  *
302  *	@dst: route's IPv4 destination address
303  *	@dst_len: destination address length (prefix length)
304  *	@fi: route FIB info structure
305  *	@tos: route TOS
306  *	@type: route type
307  *	@nlflags: netlink flags passed in (NLM_F_*)
308  *	@tb_id: route table ID
309  *
310  *	Add IPv4 route entry to switch device.
311  */
312 int netdev_switch_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
313 			       u8 tos, u8 type, u32 nlflags, u32 tb_id)
314 {
315 	struct net_device *dev;
316 	const struct swdev_ops *ops;
317 	int err = 0;
318 
319 	/* Don't offload route if using custom ip rules or if
320 	 * IPv4 FIB offloading has been disabled completely.
321 	 */
322 
323 #ifdef CONFIG_IP_MULTIPLE_TABLES
324 	if (fi->fib_net->ipv4.fib_has_custom_rules)
325 		return 0;
326 #endif
327 
328 	if (fi->fib_net->ipv4.fib_offload_disabled)
329 		return 0;
330 
331 	dev = netdev_switch_get_dev_by_nhs(fi);
332 	if (!dev)
333 		return 0;
334 	ops = dev->swdev_ops;
335 
336 	if (ops->swdev_fib_ipv4_add) {
337 		err = ops->swdev_fib_ipv4_add(dev, htonl(dst), dst_len,
338 					      fi, tos, type, nlflags,
339 					      tb_id);
340 		if (!err)
341 			fi->fib_flags |= RTNH_F_EXTERNAL;
342 	}
343 
344 	return err;
345 }
346 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_add);
347 
348 /**
349  *	netdev_switch_fib_ipv4_del - Delete IPv4 route entry from switch
350  *
351  *	@dst: route's IPv4 destination address
352  *	@dst_len: destination address length (prefix length)
353  *	@fi: route FIB info structure
354  *	@tos: route TOS
355  *	@type: route type
356  *	@tb_id: route table ID
357  *
358  *	Delete IPv4 route entry from switch device.
359  */
360 int netdev_switch_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
361 			       u8 tos, u8 type, u32 tb_id)
362 {
363 	struct net_device *dev;
364 	const struct swdev_ops *ops;
365 	int err = 0;
366 
367 	if (!(fi->fib_flags & RTNH_F_EXTERNAL))
368 		return 0;
369 
370 	dev = netdev_switch_get_dev_by_nhs(fi);
371 	if (!dev)
372 		return 0;
373 	ops = dev->swdev_ops;
374 
375 	if (ops->swdev_fib_ipv4_del) {
376 		err = ops->swdev_fib_ipv4_del(dev, htonl(dst), dst_len,
377 					      fi, tos, type, tb_id);
378 		if (!err)
379 			fi->fib_flags &= ~RTNH_F_EXTERNAL;
380 	}
381 
382 	return err;
383 }
384 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_del);
385 
386 /**
387  *	netdev_switch_fib_ipv4_abort - Abort an IPv4 FIB operation
388  *
389  *	@fi: route FIB info structure
390  */
391 void netdev_switch_fib_ipv4_abort(struct fib_info *fi)
392 {
393 	/* There was a problem installing this route to the offload
394 	 * device.  For now, until we come up with more refined
395 	 * policy handling, abruptly end IPv4 fib offloading for
396 	 * for entire net by flushing offload device(s) of all
397 	 * IPv4 routes, and mark IPv4 fib offloading broken from
398 	 * this point forward.
399 	 */
400 
401 	fib_flush_external(fi->fib_net);
402 	fi->fib_net->ipv4.fib_offload_disabled = true;
403 }
404 EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_abort);
405