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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * File: pn_dev.c
4 *
5 * Phonet network device
6 *
7 * Copyright (C) 2008 Nokia Corporation.
8 *
9 * Authors: Sakari Ailus <sakari.ailus@nokia.com>
10 * Rémi Denis-Courmont
11 */
12
13#include <linux/kernel.h>
14#include <linux/net.h>
15#include <linux/slab.h>
16#include <linux/netdevice.h>
17#include <linux/phonet.h>
18#include <linux/proc_fs.h>
19#include <linux/if_arp.h>
20#include <net/sock.h>
21#include <net/netns/generic.h>
22#include <net/phonet/pn_dev.h>
23
24struct phonet_routes {
25 struct mutex lock;
26 struct net_device __rcu *table[64];
27};
28
29struct phonet_net {
30 struct phonet_device_list pndevs;
31 struct phonet_routes routes;
32};
33
34static unsigned int phonet_net_id __read_mostly;
35
36static struct phonet_net *phonet_pernet(struct net *net)
37{
38 return net_generic(net, phonet_net_id);
39}
40
41struct phonet_device_list *phonet_device_list(struct net *net)
42{
43 struct phonet_net *pnn = phonet_pernet(net);
44 return &pnn->pndevs;
45}
46
47/* Allocate new Phonet device. */
48static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
49{
50 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
51 struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
52 if (pnd == NULL)
53 return NULL;
54 pnd->netdev = dev;
55 bitmap_zero(pnd->addrs, 64);
56
57 BUG_ON(!mutex_is_locked(&pndevs->lock));
58 list_add_rcu(&pnd->list, &pndevs->list);
59 return pnd;
60}
61
62static struct phonet_device *__phonet_get(struct net_device *dev)
63{
64 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
65 struct phonet_device *pnd;
66
67 BUG_ON(!mutex_is_locked(&pndevs->lock));
68 list_for_each_entry(pnd, &pndevs->list, list) {
69 if (pnd->netdev == dev)
70 return pnd;
71 }
72 return NULL;
73}
74
75static struct phonet_device *__phonet_get_rcu(struct net_device *dev)
76{
77 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
78 struct phonet_device *pnd;
79
80 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
81 if (pnd->netdev == dev)
82 return pnd;
83 }
84 return NULL;
85}
86
87static void phonet_device_destroy(struct net_device *dev)
88{
89 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
90 struct phonet_device *pnd;
91
92 ASSERT_RTNL();
93
94 mutex_lock(&pndevs->lock);
95 pnd = __phonet_get(dev);
96 if (pnd)
97 list_del_rcu(&pnd->list);
98 mutex_unlock(&pndevs->lock);
99
100 if (pnd) {
101 u8 addr;
102
103 for_each_set_bit(addr, pnd->addrs, 64)
104 phonet_address_notify(RTM_DELADDR, dev, addr);
105 kfree(pnd);
106 }
107}
108
109struct net_device *phonet_device_get(struct net *net)
110{
111 struct phonet_device_list *pndevs = phonet_device_list(net);
112 struct phonet_device *pnd;
113 struct net_device *dev = NULL;
114
115 rcu_read_lock();
116 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
117 dev = pnd->netdev;
118 BUG_ON(!dev);
119
120 if ((dev->reg_state == NETREG_REGISTERED) &&
121 ((pnd->netdev->flags & IFF_UP)) == IFF_UP)
122 break;
123 dev = NULL;
124 }
125 dev_hold(dev);
126 rcu_read_unlock();
127 return dev;
128}
129
130int phonet_address_add(struct net_device *dev, u8 addr)
131{
132 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
133 struct phonet_device *pnd;
134 int err = 0;
135
136 mutex_lock(&pndevs->lock);
137 /* Find or create Phonet-specific device data */
138 pnd = __phonet_get(dev);
139 if (pnd == NULL)
140 pnd = __phonet_device_alloc(dev);
141 if (unlikely(pnd == NULL))
142 err = -ENOMEM;
143 else if (test_and_set_bit(addr >> 2, pnd->addrs))
144 err = -EEXIST;
145 mutex_unlock(&pndevs->lock);
146 return err;
147}
148
149int phonet_address_del(struct net_device *dev, u8 addr)
150{
151 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
152 struct phonet_device *pnd;
153 int err = 0;
154
155 mutex_lock(&pndevs->lock);
156 pnd = __phonet_get(dev);
157 if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) {
158 err = -EADDRNOTAVAIL;
159 pnd = NULL;
160 } else if (bitmap_empty(pnd->addrs, 64))
161 list_del_rcu(&pnd->list);
162 else
163 pnd = NULL;
164 mutex_unlock(&pndevs->lock);
165
166 if (pnd)
167 kfree_rcu(pnd, rcu);
168
169 return err;
170}
171
172/* Gets a source address toward a destination, through a interface. */
173u8 phonet_address_get(struct net_device *dev, u8 daddr)
174{
175 struct phonet_device *pnd;
176 u8 saddr;
177
178 rcu_read_lock();
179 pnd = __phonet_get_rcu(dev);
180 if (pnd) {
181 BUG_ON(bitmap_empty(pnd->addrs, 64));
182
183 /* Use same source address as destination, if possible */
184 if (test_bit(daddr >> 2, pnd->addrs))
185 saddr = daddr;
186 else
187 saddr = find_first_bit(pnd->addrs, 64) << 2;
188 } else
189 saddr = PN_NO_ADDR;
190 rcu_read_unlock();
191
192 if (saddr == PN_NO_ADDR) {
193 /* Fallback to another device */
194 struct net_device *def_dev;
195
196 def_dev = phonet_device_get(dev_net(dev));
197 if (def_dev) {
198 if (def_dev != dev)
199 saddr = phonet_address_get(def_dev, daddr);
200 dev_put(def_dev);
201 }
202 }
203 return saddr;
204}
205
206int phonet_address_lookup(struct net *net, u8 addr)
207{
208 struct phonet_device_list *pndevs = phonet_device_list(net);
209 struct phonet_device *pnd;
210 int err = -EADDRNOTAVAIL;
211
212 rcu_read_lock();
213 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
214 /* Don't allow unregistering devices! */
215 if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
216 ((pnd->netdev->flags & IFF_UP)) != IFF_UP)
217 continue;
218
219 if (test_bit(addr >> 2, pnd->addrs)) {
220 err = 0;
221 goto found;
222 }
223 }
224found:
225 rcu_read_unlock();
226 return err;
227}
228
229/* automatically configure a Phonet device, if supported */
230static int phonet_device_autoconf(struct net_device *dev)
231{
232 struct if_phonet_req req;
233 int ret;
234
235 if (!dev->netdev_ops->ndo_siocdevprivate)
236 return -EOPNOTSUPP;
237
238 ret = dev->netdev_ops->ndo_siocdevprivate(dev, (struct ifreq *)&req,
239 NULL, SIOCPNGAUTOCONF);
240 if (ret < 0)
241 return ret;
242
243 ASSERT_RTNL();
244 ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
245 if (ret)
246 return ret;
247 phonet_address_notify(RTM_NEWADDR, dev,
248 req.ifr_phonet_autoconf.device);
249 return 0;
250}
251
252static void phonet_route_autodel(struct net_device *dev)
253{
254 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
255 unsigned int i;
256 DECLARE_BITMAP(deleted, 64);
257
258 /* Remove left-over Phonet routes */
259 bitmap_zero(deleted, 64);
260 mutex_lock(&pnn->routes.lock);
261 for (i = 0; i < 64; i++)
262 if (rcu_access_pointer(pnn->routes.table[i]) == dev) {
263 RCU_INIT_POINTER(pnn->routes.table[i], NULL);
264 set_bit(i, deleted);
265 }
266 mutex_unlock(&pnn->routes.lock);
267
268 if (bitmap_empty(deleted, 64))
269 return; /* short-circuit RCU */
270 synchronize_rcu();
271 for_each_set_bit(i, deleted, 64) {
272 rtm_phonet_notify(RTM_DELROUTE, dev, i);
273 dev_put(dev);
274 }
275}
276
277/* notify Phonet of device events */
278static int phonet_device_notify(struct notifier_block *me, unsigned long what,
279 void *ptr)
280{
281 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
282
283 switch (what) {
284 case NETDEV_REGISTER:
285 if (dev->type == ARPHRD_PHONET)
286 phonet_device_autoconf(dev);
287 break;
288 case NETDEV_UNREGISTER:
289 phonet_device_destroy(dev);
290 phonet_route_autodel(dev);
291 break;
292 }
293 return 0;
294
295}
296
297static struct notifier_block phonet_device_notifier = {
298 .notifier_call = phonet_device_notify,
299 .priority = 0,
300};
301
302/* Per-namespace Phonet devices handling */
303static int __net_init phonet_init_net(struct net *net)
304{
305 struct phonet_net *pnn = phonet_pernet(net);
306
307 if (!proc_create_net("phonet", 0, net->proc_net, &pn_sock_seq_ops,
308 sizeof(struct seq_net_private)))
309 return -ENOMEM;
310
311 INIT_LIST_HEAD(&pnn->pndevs.list);
312 mutex_init(&pnn->pndevs.lock);
313 mutex_init(&pnn->routes.lock);
314 return 0;
315}
316
317static void __net_exit phonet_exit_net(struct net *net)
318{
319 struct phonet_net *pnn = phonet_pernet(net);
320
321 remove_proc_entry("phonet", net->proc_net);
322 WARN_ON_ONCE(!list_empty(&pnn->pndevs.list));
323}
324
325static struct pernet_operations phonet_net_ops = {
326 .init = phonet_init_net,
327 .exit = phonet_exit_net,
328 .id = &phonet_net_id,
329 .size = sizeof(struct phonet_net),
330};
331
332/* Initialize Phonet devices list */
333int __init phonet_device_init(void)
334{
335 int err = register_pernet_subsys(&phonet_net_ops);
336 if (err)
337 return err;
338
339 proc_create_net("pnresource", 0, init_net.proc_net, &pn_res_seq_ops,
340 sizeof(struct seq_net_private));
341 register_netdevice_notifier(&phonet_device_notifier);
342 err = phonet_netlink_register();
343 if (err)
344 phonet_device_exit();
345 return err;
346}
347
348void phonet_device_exit(void)
349{
350 rtnl_unregister_all(PF_PHONET);
351 unregister_netdevice_notifier(&phonet_device_notifier);
352 unregister_pernet_subsys(&phonet_net_ops);
353 remove_proc_entry("pnresource", init_net.proc_net);
354}
355
356int phonet_route_add(struct net_device *dev, u8 daddr)
357{
358 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
359 struct phonet_routes *routes = &pnn->routes;
360 int err = -EEXIST;
361
362 daddr = daddr >> 2;
363 mutex_lock(&routes->lock);
364 if (routes->table[daddr] == NULL) {
365 rcu_assign_pointer(routes->table[daddr], dev);
366 dev_hold(dev);
367 err = 0;
368 }
369 mutex_unlock(&routes->lock);
370 return err;
371}
372
373int phonet_route_del(struct net_device *dev, u8 daddr)
374{
375 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
376 struct phonet_routes *routes = &pnn->routes;
377
378 daddr = daddr >> 2;
379 mutex_lock(&routes->lock);
380 if (rcu_access_pointer(routes->table[daddr]) == dev)
381 RCU_INIT_POINTER(routes->table[daddr], NULL);
382 else
383 dev = NULL;
384 mutex_unlock(&routes->lock);
385
386 if (!dev)
387 return -ENOENT;
388 synchronize_rcu();
389 dev_put(dev);
390 return 0;
391}
392
393struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr)
394{
395 struct phonet_net *pnn = phonet_pernet(net);
396 struct phonet_routes *routes = &pnn->routes;
397 struct net_device *dev;
398
399 daddr >>= 2;
400 dev = rcu_dereference(routes->table[daddr]);
401 return dev;
402}
403
404struct net_device *phonet_route_output(struct net *net, u8 daddr)
405{
406 struct phonet_net *pnn = phonet_pernet(net);
407 struct phonet_routes *routes = &pnn->routes;
408 struct net_device *dev;
409
410 daddr >>= 2;
411 rcu_read_lock();
412 dev = rcu_dereference(routes->table[daddr]);
413 dev_hold(dev);
414 rcu_read_unlock();
415
416 if (!dev)
417 dev = phonet_device_get(net); /* Default route */
418 return dev;
419}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * File: pn_dev.c
4 *
5 * Phonet network device
6 *
7 * Copyright (C) 2008 Nokia Corporation.
8 *
9 * Authors: Sakari Ailus <sakari.ailus@nokia.com>
10 * Rémi Denis-Courmont
11 */
12
13#include <linux/kernel.h>
14#include <linux/net.h>
15#include <linux/slab.h>
16#include <linux/netdevice.h>
17#include <linux/phonet.h>
18#include <linux/proc_fs.h>
19#include <linux/if_arp.h>
20#include <net/sock.h>
21#include <net/netns/generic.h>
22#include <net/phonet/pn_dev.h>
23
24struct phonet_routes {
25 struct mutex lock;
26 struct net_device __rcu *table[64];
27};
28
29struct phonet_net {
30 struct phonet_device_list pndevs;
31 struct phonet_routes routes;
32};
33
34static unsigned int phonet_net_id __read_mostly;
35
36static struct phonet_net *phonet_pernet(struct net *net)
37{
38 return net_generic(net, phonet_net_id);
39}
40
41struct phonet_device_list *phonet_device_list(struct net *net)
42{
43 struct phonet_net *pnn = phonet_pernet(net);
44 return &pnn->pndevs;
45}
46
47/* Allocate new Phonet device. */
48static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
49{
50 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
51 struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
52 if (pnd == NULL)
53 return NULL;
54 pnd->netdev = dev;
55 bitmap_zero(pnd->addrs, 64);
56
57 BUG_ON(!mutex_is_locked(&pndevs->lock));
58 list_add_rcu(&pnd->list, &pndevs->list);
59 return pnd;
60}
61
62static struct phonet_device *__phonet_get(struct net_device *dev)
63{
64 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
65 struct phonet_device *pnd;
66
67 BUG_ON(!mutex_is_locked(&pndevs->lock));
68 list_for_each_entry(pnd, &pndevs->list, list) {
69 if (pnd->netdev == dev)
70 return pnd;
71 }
72 return NULL;
73}
74
75static struct phonet_device *__phonet_get_rcu(struct net_device *dev)
76{
77 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
78 struct phonet_device *pnd;
79
80 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
81 if (pnd->netdev == dev)
82 return pnd;
83 }
84 return NULL;
85}
86
87static void phonet_device_destroy(struct net_device *dev)
88{
89 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
90 struct phonet_device *pnd;
91
92 ASSERT_RTNL();
93
94 mutex_lock(&pndevs->lock);
95 pnd = __phonet_get(dev);
96 if (pnd)
97 list_del_rcu(&pnd->list);
98 mutex_unlock(&pndevs->lock);
99
100 if (pnd) {
101 u8 addr;
102
103 for_each_set_bit(addr, pnd->addrs, 64)
104 phonet_address_notify(RTM_DELADDR, dev, addr);
105 kfree(pnd);
106 }
107}
108
109struct net_device *phonet_device_get(struct net *net)
110{
111 struct phonet_device_list *pndevs = phonet_device_list(net);
112 struct phonet_device *pnd;
113 struct net_device *dev = NULL;
114
115 rcu_read_lock();
116 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
117 dev = pnd->netdev;
118 BUG_ON(!dev);
119
120 if ((dev->reg_state == NETREG_REGISTERED) &&
121 ((pnd->netdev->flags & IFF_UP)) == IFF_UP)
122 break;
123 dev = NULL;
124 }
125 if (dev)
126 dev_hold(dev);
127 rcu_read_unlock();
128 return dev;
129}
130
131int phonet_address_add(struct net_device *dev, u8 addr)
132{
133 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
134 struct phonet_device *pnd;
135 int err = 0;
136
137 mutex_lock(&pndevs->lock);
138 /* Find or create Phonet-specific device data */
139 pnd = __phonet_get(dev);
140 if (pnd == NULL)
141 pnd = __phonet_device_alloc(dev);
142 if (unlikely(pnd == NULL))
143 err = -ENOMEM;
144 else if (test_and_set_bit(addr >> 2, pnd->addrs))
145 err = -EEXIST;
146 mutex_unlock(&pndevs->lock);
147 return err;
148}
149
150int phonet_address_del(struct net_device *dev, u8 addr)
151{
152 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
153 struct phonet_device *pnd;
154 int err = 0;
155
156 mutex_lock(&pndevs->lock);
157 pnd = __phonet_get(dev);
158 if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) {
159 err = -EADDRNOTAVAIL;
160 pnd = NULL;
161 } else if (bitmap_empty(pnd->addrs, 64))
162 list_del_rcu(&pnd->list);
163 else
164 pnd = NULL;
165 mutex_unlock(&pndevs->lock);
166
167 if (pnd)
168 kfree_rcu(pnd, rcu);
169
170 return err;
171}
172
173/* Gets a source address toward a destination, through a interface. */
174u8 phonet_address_get(struct net_device *dev, u8 daddr)
175{
176 struct phonet_device *pnd;
177 u8 saddr;
178
179 rcu_read_lock();
180 pnd = __phonet_get_rcu(dev);
181 if (pnd) {
182 BUG_ON(bitmap_empty(pnd->addrs, 64));
183
184 /* Use same source address as destination, if possible */
185 if (test_bit(daddr >> 2, pnd->addrs))
186 saddr = daddr;
187 else
188 saddr = find_first_bit(pnd->addrs, 64) << 2;
189 } else
190 saddr = PN_NO_ADDR;
191 rcu_read_unlock();
192
193 if (saddr == PN_NO_ADDR) {
194 /* Fallback to another device */
195 struct net_device *def_dev;
196
197 def_dev = phonet_device_get(dev_net(dev));
198 if (def_dev) {
199 if (def_dev != dev)
200 saddr = phonet_address_get(def_dev, daddr);
201 dev_put(def_dev);
202 }
203 }
204 return saddr;
205}
206
207int phonet_address_lookup(struct net *net, u8 addr)
208{
209 struct phonet_device_list *pndevs = phonet_device_list(net);
210 struct phonet_device *pnd;
211 int err = -EADDRNOTAVAIL;
212
213 rcu_read_lock();
214 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
215 /* Don't allow unregistering devices! */
216 if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
217 ((pnd->netdev->flags & IFF_UP)) != IFF_UP)
218 continue;
219
220 if (test_bit(addr >> 2, pnd->addrs)) {
221 err = 0;
222 goto found;
223 }
224 }
225found:
226 rcu_read_unlock();
227 return err;
228}
229
230/* automatically configure a Phonet device, if supported */
231static int phonet_device_autoconf(struct net_device *dev)
232{
233 struct if_phonet_req req;
234 int ret;
235
236 if (!dev->netdev_ops->ndo_do_ioctl)
237 return -EOPNOTSUPP;
238
239 ret = dev->netdev_ops->ndo_do_ioctl(dev, (struct ifreq *)&req,
240 SIOCPNGAUTOCONF);
241 if (ret < 0)
242 return ret;
243
244 ASSERT_RTNL();
245 ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
246 if (ret)
247 return ret;
248 phonet_address_notify(RTM_NEWADDR, dev,
249 req.ifr_phonet_autoconf.device);
250 return 0;
251}
252
253static void phonet_route_autodel(struct net_device *dev)
254{
255 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
256 unsigned int i;
257 DECLARE_BITMAP(deleted, 64);
258
259 /* Remove left-over Phonet routes */
260 bitmap_zero(deleted, 64);
261 mutex_lock(&pnn->routes.lock);
262 for (i = 0; i < 64; i++)
263 if (rcu_access_pointer(pnn->routes.table[i]) == dev) {
264 RCU_INIT_POINTER(pnn->routes.table[i], NULL);
265 set_bit(i, deleted);
266 }
267 mutex_unlock(&pnn->routes.lock);
268
269 if (bitmap_empty(deleted, 64))
270 return; /* short-circuit RCU */
271 synchronize_rcu();
272 for_each_set_bit(i, deleted, 64) {
273 rtm_phonet_notify(RTM_DELROUTE, dev, i);
274 dev_put(dev);
275 }
276}
277
278/* notify Phonet of device events */
279static int phonet_device_notify(struct notifier_block *me, unsigned long what,
280 void *ptr)
281{
282 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
283
284 switch (what) {
285 case NETDEV_REGISTER:
286 if (dev->type == ARPHRD_PHONET)
287 phonet_device_autoconf(dev);
288 break;
289 case NETDEV_UNREGISTER:
290 phonet_device_destroy(dev);
291 phonet_route_autodel(dev);
292 break;
293 }
294 return 0;
295
296}
297
298static struct notifier_block phonet_device_notifier = {
299 .notifier_call = phonet_device_notify,
300 .priority = 0,
301};
302
303/* Per-namespace Phonet devices handling */
304static int __net_init phonet_init_net(struct net *net)
305{
306 struct phonet_net *pnn = phonet_pernet(net);
307
308 if (!proc_create_net("phonet", 0, net->proc_net, &pn_sock_seq_ops,
309 sizeof(struct seq_net_private)))
310 return -ENOMEM;
311
312 INIT_LIST_HEAD(&pnn->pndevs.list);
313 mutex_init(&pnn->pndevs.lock);
314 mutex_init(&pnn->routes.lock);
315 return 0;
316}
317
318static void __net_exit phonet_exit_net(struct net *net)
319{
320 struct phonet_net *pnn = phonet_pernet(net);
321
322 remove_proc_entry("phonet", net->proc_net);
323 WARN_ON_ONCE(!list_empty(&pnn->pndevs.list));
324}
325
326static struct pernet_operations phonet_net_ops = {
327 .init = phonet_init_net,
328 .exit = phonet_exit_net,
329 .id = &phonet_net_id,
330 .size = sizeof(struct phonet_net),
331};
332
333/* Initialize Phonet devices list */
334int __init phonet_device_init(void)
335{
336 int err = register_pernet_subsys(&phonet_net_ops);
337 if (err)
338 return err;
339
340 proc_create_net("pnresource", 0, init_net.proc_net, &pn_res_seq_ops,
341 sizeof(struct seq_net_private));
342 register_netdevice_notifier(&phonet_device_notifier);
343 err = phonet_netlink_register();
344 if (err)
345 phonet_device_exit();
346 return err;
347}
348
349void phonet_device_exit(void)
350{
351 rtnl_unregister_all(PF_PHONET);
352 unregister_netdevice_notifier(&phonet_device_notifier);
353 unregister_pernet_subsys(&phonet_net_ops);
354 remove_proc_entry("pnresource", init_net.proc_net);
355}
356
357int phonet_route_add(struct net_device *dev, u8 daddr)
358{
359 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
360 struct phonet_routes *routes = &pnn->routes;
361 int err = -EEXIST;
362
363 daddr = daddr >> 2;
364 mutex_lock(&routes->lock);
365 if (routes->table[daddr] == NULL) {
366 rcu_assign_pointer(routes->table[daddr], dev);
367 dev_hold(dev);
368 err = 0;
369 }
370 mutex_unlock(&routes->lock);
371 return err;
372}
373
374int phonet_route_del(struct net_device *dev, u8 daddr)
375{
376 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
377 struct phonet_routes *routes = &pnn->routes;
378
379 daddr = daddr >> 2;
380 mutex_lock(&routes->lock);
381 if (rcu_access_pointer(routes->table[daddr]) == dev)
382 RCU_INIT_POINTER(routes->table[daddr], NULL);
383 else
384 dev = NULL;
385 mutex_unlock(&routes->lock);
386
387 if (!dev)
388 return -ENOENT;
389 synchronize_rcu();
390 dev_put(dev);
391 return 0;
392}
393
394struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr)
395{
396 struct phonet_net *pnn = phonet_pernet(net);
397 struct phonet_routes *routes = &pnn->routes;
398 struct net_device *dev;
399
400 daddr >>= 2;
401 dev = rcu_dereference(routes->table[daddr]);
402 return dev;
403}
404
405struct net_device *phonet_route_output(struct net *net, u8 daddr)
406{
407 struct phonet_net *pnn = phonet_pernet(net);
408 struct phonet_routes *routes = &pnn->routes;
409 struct net_device *dev;
410
411 daddr >>= 2;
412 rcu_read_lock();
413 dev = rcu_dereference(routes->table[daddr]);
414 if (dev)
415 dev_hold(dev);
416 rcu_read_unlock();
417
418 if (!dev)
419 dev = phonet_device_get(net); /* Default route */
420 return dev;
421}