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 <linux/rtnetlink.h>
19#include <net/ip_fib.h>
20#include <net/switchdev.h>
21
22/**
23 *	netdev_switch_parent_id_get - Get ID of a switch
24 *	@dev: port device
25 *	@psid: switch ID
26 *
27 *	Get ID of a switch this port is part of.
28 */
29int netdev_switch_parent_id_get(struct net_device *dev,
30				struct netdev_phys_item_id *psid)
31{
32	const struct swdev_ops *ops = dev->swdev_ops;
33
34	if (!ops || !ops->swdev_parent_id_get)
35		return -EOPNOTSUPP;
36	return ops->swdev_parent_id_get(dev, psid);
37}
38EXPORT_SYMBOL_GPL(netdev_switch_parent_id_get);
39
40/**
41 *	netdev_switch_port_stp_update - Notify switch device port of STP
42 *					state change
43 *	@dev: port device
44 *	@state: port STP state
45 *
46 *	Notify switch device port of bridge port STP state change.
47 */
48int netdev_switch_port_stp_update(struct net_device *dev, u8 state)
49{
50	const struct swdev_ops *ops = dev->swdev_ops;
51	struct net_device *lower_dev;
52	struct list_head *iter;
53	int err = -EOPNOTSUPP;
54
55	if (ops && ops->swdev_port_stp_update)
56		return ops->swdev_port_stp_update(dev, state);
57
58	netdev_for_each_lower_dev(dev, lower_dev, iter) {
59		err = netdev_switch_port_stp_update(lower_dev, state);
60		if (err && err != -EOPNOTSUPP)
61			return err;
62	}
63
64	return err;
65}
66EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
67
68static 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 */
78int register_netdev_switch_notifier(struct notifier_block *nb)
79{
80	int err;
81
82	rtnl_lock();
83	err = raw_notifier_chain_register(&netdev_switch_notif_chain, nb);
84	rtnl_unlock();
85	return err;
86}
87EXPORT_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 */
96int unregister_netdev_switch_notifier(struct notifier_block *nb)
97{
98	int err;
99
100	rtnl_lock();
101	err = raw_notifier_chain_unregister(&netdev_switch_notif_chain, nb);
102	rtnl_unlock();
103	return err;
104}
105EXPORT_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 *	rtnl_lock must be held.
117 */
118int call_netdev_switch_notifiers(unsigned long val, struct net_device *dev,
119				 struct netdev_switch_notifier_info *info)
120{
121	int err;
122
123	ASSERT_RTNL();
124
125	info->dev = dev;
126	err = raw_notifier_call_chain(&netdev_switch_notif_chain, val, info);
127	return err;
128}
129EXPORT_SYMBOL_GPL(call_netdev_switch_notifiers);
130
131/**
132 *	netdev_switch_port_bridge_setlink - Notify switch device port of bridge
133 *	port attributes
134 *
135 *	@dev: port device
136 *	@nlh: netlink msg with bridge port attributes
137 *	@flags: bridge setlink flags
138 *
139 *	Notify switch device port of bridge port attributes
140 */
141int netdev_switch_port_bridge_setlink(struct net_device *dev,
142				      struct nlmsghdr *nlh, u16 flags)
143{
144	const struct net_device_ops *ops = dev->netdev_ops;
145
146	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
147		return 0;
148
149	if (!ops->ndo_bridge_setlink)
150		return -EOPNOTSUPP;
151
152	return ops->ndo_bridge_setlink(dev, nlh, flags);
153}
154EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_setlink);
155
156/**
157 *	netdev_switch_port_bridge_dellink - Notify switch device port of bridge
158 *	port attribute delete
159 *
160 *	@dev: port device
161 *	@nlh: netlink msg with bridge port attributes
162 *	@flags: bridge setlink flags
163 *
164 *	Notify switch device port of bridge port attribute delete
165 */
166int netdev_switch_port_bridge_dellink(struct net_device *dev,
167				      struct nlmsghdr *nlh, u16 flags)
168{
169	const struct net_device_ops *ops = dev->netdev_ops;
170
171	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
172		return 0;
173
174	if (!ops->ndo_bridge_dellink)
175		return -EOPNOTSUPP;
176
177	return ops->ndo_bridge_dellink(dev, nlh, flags);
178}
179EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_dellink);
180
181/**
182 *	ndo_dflt_netdev_switch_port_bridge_setlink - default ndo bridge setlink
183 *						     op for master devices
184 *
185 *	@dev: port device
186 *	@nlh: netlink msg with bridge port attributes
187 *	@flags: bridge setlink flags
188 *
189 *	Notify master device slaves of bridge port attributes
190 */
191int ndo_dflt_netdev_switch_port_bridge_setlink(struct net_device *dev,
192					       struct nlmsghdr *nlh, u16 flags)
193{
194	struct net_device *lower_dev;
195	struct list_head *iter;
196	int ret = 0, err = 0;
197
198	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
199		return ret;
200
201	netdev_for_each_lower_dev(dev, lower_dev, iter) {
202		err = netdev_switch_port_bridge_setlink(lower_dev, nlh, flags);
203		if (err && err != -EOPNOTSUPP)
204			ret = err;
205	}
206
207	return ret;
208}
209EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_setlink);
210
211/**
212 *	ndo_dflt_netdev_switch_port_bridge_dellink - default ndo bridge dellink
213 *						     op for master devices
214 *
215 *	@dev: port device
216 *	@nlh: netlink msg with bridge port attributes
217 *	@flags: bridge dellink flags
218 *
219 *	Notify master device slaves of bridge port attribute deletes
220 */
221int ndo_dflt_netdev_switch_port_bridge_dellink(struct net_device *dev,
222					       struct nlmsghdr *nlh, u16 flags)
223{
224	struct net_device *lower_dev;
225	struct list_head *iter;
226	int ret = 0, err = 0;
227
228	if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
229		return ret;
230
231	netdev_for_each_lower_dev(dev, lower_dev, iter) {
232		err = netdev_switch_port_bridge_dellink(lower_dev, nlh, flags);
233		if (err && err != -EOPNOTSUPP)
234			ret = err;
235	}
236
237	return ret;
238}
239EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_dellink);
240
241static struct net_device *netdev_switch_get_lowest_dev(struct net_device *dev)
242{
243	const struct swdev_ops *ops = dev->swdev_ops;
244	struct net_device *lower_dev;
245	struct net_device *port_dev;
246	struct list_head *iter;
247
248	/* Recusively search down until we find a sw port dev.
249	 * (A sw port dev supports swdev_parent_id_get).
250	 */
251
252	if (dev->features & NETIF_F_HW_SWITCH_OFFLOAD &&
253	    ops && ops->swdev_parent_id_get)
254		return dev;
255
256	netdev_for_each_lower_dev(dev, lower_dev, iter) {
257		port_dev = netdev_switch_get_lowest_dev(lower_dev);
258		if (port_dev)
259			return port_dev;
260	}
261
262	return NULL;
263}
264
265static struct net_device *netdev_switch_get_dev_by_nhs(struct fib_info *fi)
266{
267	struct netdev_phys_item_id psid;
268	struct netdev_phys_item_id prev_psid;
269	struct net_device *dev = NULL;
270	int nhsel;
271
272	/* For this route, all nexthop devs must be on the same switch. */
273
274	for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
275		const struct fib_nh *nh = &fi->fib_nh[nhsel];
276
277		if (!nh->nh_dev)
278			return NULL;
279
280		dev = netdev_switch_get_lowest_dev(nh->nh_dev);
281		if (!dev)
282			return NULL;
283
284		if (netdev_switch_parent_id_get(dev, &psid))
285			return NULL;
286
287		if (nhsel > 0) {
288			if (prev_psid.id_len != psid.id_len)
289				return NULL;
290			if (memcmp(prev_psid.id, psid.id, psid.id_len))
291				return NULL;
292		}
293
294		prev_psid = psid;
295	}
296
297	return dev;
298}
299
300/**
301 *	netdev_switch_fib_ipv4_add - Add IPv4 route entry to switch
302 *
303 *	@dst: route's IPv4 destination address
304 *	@dst_len: destination address length (prefix length)
305 *	@fi: route FIB info structure
306 *	@tos: route TOS
307 *	@type: route type
308 *	@nlflags: netlink flags passed in (NLM_F_*)
309 *	@tb_id: route table ID
310 *
311 *	Add IPv4 route entry to switch device.
312 */
313int netdev_switch_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
314			       u8 tos, u8 type, u32 nlflags, u32 tb_id)
315{
316	struct net_device *dev;
317	const struct swdev_ops *ops;
318	int err = 0;
319
320	/* Don't offload route if using custom ip rules or if
321	 * IPv4 FIB offloading has been disabled completely.
322	 */
323
324#ifdef CONFIG_IP_MULTIPLE_TABLES
325	if (fi->fib_net->ipv4.fib_has_custom_rules)
326		return 0;
327#endif
328
329	if (fi->fib_net->ipv4.fib_offload_disabled)
330		return 0;
331
332	dev = netdev_switch_get_dev_by_nhs(fi);
333	if (!dev)
334		return 0;
335	ops = dev->swdev_ops;
336
337	if (ops->swdev_fib_ipv4_add) {
338		err = ops->swdev_fib_ipv4_add(dev, htonl(dst), dst_len,
339					      fi, tos, type, nlflags,
340					      tb_id);
341		if (!err)
342			fi->fib_flags |= RTNH_F_OFFLOAD;
343	}
344
345	return err;
346}
347EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_add);
348
349/**
350 *	netdev_switch_fib_ipv4_del - Delete IPv4 route entry from switch
351 *
352 *	@dst: route's IPv4 destination address
353 *	@dst_len: destination address length (prefix length)
354 *	@fi: route FIB info structure
355 *	@tos: route TOS
356 *	@type: route type
357 *	@tb_id: route table ID
358 *
359 *	Delete IPv4 route entry from switch device.
360 */
361int netdev_switch_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
362			       u8 tos, u8 type, u32 tb_id)
363{
364	struct net_device *dev;
365	const struct swdev_ops *ops;
366	int err = 0;
367
368	if (!(fi->fib_flags & RTNH_F_OFFLOAD))
369		return 0;
370
371	dev = netdev_switch_get_dev_by_nhs(fi);
372	if (!dev)
373		return 0;
374	ops = dev->swdev_ops;
375
376	if (ops->swdev_fib_ipv4_del) {
377		err = ops->swdev_fib_ipv4_del(dev, htonl(dst), dst_len,
378					      fi, tos, type, tb_id);
379		if (!err)
380			fi->fib_flags &= ~RTNH_F_OFFLOAD;
381	}
382
383	return err;
384}
385EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_del);
386
387/**
388 *	netdev_switch_fib_ipv4_abort - Abort an IPv4 FIB operation
389 *
390 *	@fi: route FIB info structure
391 */
392void netdev_switch_fib_ipv4_abort(struct fib_info *fi)
393{
394	/* There was a problem installing this route to the offload
395	 * device.  For now, until we come up with more refined
396	 * policy handling, abruptly end IPv4 fib offloading for
397	 * for entire net by flushing offload device(s) of all
398	 * IPv4 routes, and mark IPv4 fib offloading broken from
399	 * this point forward.
400	 */
401
402	fib_flush_external(fi->fib_net);
403	fi->fib_net->ipv4.fib_offload_disabled = true;
404}
405EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_abort);
406