Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / phonet / pn_dev.c
blobd2df8f33160bd1db3e659a9e9dc83f1b879e44bb
1 /*
2 * File: pn_dev.c
4 * Phonet network device
6 * Copyright (C) 2008 Nokia Corporation.
8 * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
9 * Original author: Sakari Ailus <sakari.ailus@nokia.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * version 2 as published by the Free Software Foundation.
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
23 * 02110-1301 USA
26 #include <linux/kernel.h>
27 #include <linux/net.h>
28 #include <linux/slab.h>
29 #include <linux/netdevice.h>
30 #include <linux/phonet.h>
31 #include <linux/proc_fs.h>
32 #include <linux/if_arp.h>
33 #include <net/sock.h>
34 #include <net/netns/generic.h>
35 #include <net/phonet/pn_dev.h>
37 struct phonet_routes {
38 struct mutex lock;
39 struct net_device *table[64];
42 struct phonet_net {
43 struct phonet_device_list pndevs;
44 struct phonet_routes routes;
47 int phonet_net_id __read_mostly;
49 static struct phonet_net *phonet_pernet(struct net *net)
51 BUG_ON(!net);
53 return net_generic(net, phonet_net_id);
56 struct phonet_device_list *phonet_device_list(struct net *net)
58 struct phonet_net *pnn = phonet_pernet(net);
59 return &pnn->pndevs;
62 /* Allocate new Phonet device. */
63 static struct phonet_device *__phonet_device_alloc(struct net_device *dev)
65 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
66 struct phonet_device *pnd = kmalloc(sizeof(*pnd), GFP_ATOMIC);
67 if (pnd == NULL)
68 return NULL;
69 pnd->netdev = dev;
70 bitmap_zero(pnd->addrs, 64);
72 BUG_ON(!mutex_is_locked(&pndevs->lock));
73 list_add_rcu(&pnd->list, &pndevs->list);
74 return pnd;
77 static struct phonet_device *__phonet_get(struct net_device *dev)
79 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
80 struct phonet_device *pnd;
82 BUG_ON(!mutex_is_locked(&pndevs->lock));
83 list_for_each_entry(pnd, &pndevs->list, list) {
84 if (pnd->netdev == dev)
85 return pnd;
87 return NULL;
90 static struct phonet_device *__phonet_get_rcu(struct net_device *dev)
92 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
93 struct phonet_device *pnd;
95 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
96 if (pnd->netdev == dev)
97 return pnd;
99 return NULL;
102 static void phonet_device_destroy(struct net_device *dev)
104 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
105 struct phonet_device *pnd;
107 ASSERT_RTNL();
109 mutex_lock(&pndevs->lock);
110 pnd = __phonet_get(dev);
111 if (pnd)
112 list_del_rcu(&pnd->list);
113 mutex_unlock(&pndevs->lock);
115 if (pnd) {
116 u8 addr;
118 for_each_set_bit(addr, pnd->addrs, 64)
119 phonet_address_notify(RTM_DELADDR, dev, addr);
120 kfree(pnd);
124 struct net_device *phonet_device_get(struct net *net)
126 struct phonet_device_list *pndevs = phonet_device_list(net);
127 struct phonet_device *pnd;
128 struct net_device *dev = NULL;
130 rcu_read_lock();
131 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
132 dev = pnd->netdev;
133 BUG_ON(!dev);
135 if ((dev->reg_state == NETREG_REGISTERED) &&
136 ((pnd->netdev->flags & IFF_UP)) == IFF_UP)
137 break;
138 dev = NULL;
140 if (dev)
141 dev_hold(dev);
142 rcu_read_unlock();
143 return dev;
146 int phonet_address_add(struct net_device *dev, u8 addr)
148 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
149 struct phonet_device *pnd;
150 int err = 0;
152 mutex_lock(&pndevs->lock);
153 /* Find or create Phonet-specific device data */
154 pnd = __phonet_get(dev);
155 if (pnd == NULL)
156 pnd = __phonet_device_alloc(dev);
157 if (unlikely(pnd == NULL))
158 err = -ENOMEM;
159 else if (test_and_set_bit(addr >> 2, pnd->addrs))
160 err = -EEXIST;
161 mutex_unlock(&pndevs->lock);
162 return err;
165 int phonet_address_del(struct net_device *dev, u8 addr)
167 struct phonet_device_list *pndevs = phonet_device_list(dev_net(dev));
168 struct phonet_device *pnd;
169 int err = 0;
171 mutex_lock(&pndevs->lock);
172 pnd = __phonet_get(dev);
173 if (!pnd || !test_and_clear_bit(addr >> 2, pnd->addrs)) {
174 err = -EADDRNOTAVAIL;
175 pnd = NULL;
176 } else if (bitmap_empty(pnd->addrs, 64))
177 list_del_rcu(&pnd->list);
178 else
179 pnd = NULL;
180 mutex_unlock(&pndevs->lock);
182 if (pnd)
183 kfree_rcu(pnd, rcu);
185 return err;
188 /* Gets a source address toward a destination, through a interface. */
189 u8 phonet_address_get(struct net_device *dev, u8 daddr)
191 struct phonet_device *pnd;
192 u8 saddr;
194 rcu_read_lock();
195 pnd = __phonet_get_rcu(dev);
196 if (pnd) {
197 BUG_ON(bitmap_empty(pnd->addrs, 64));
199 /* Use same source address as destination, if possible */
200 if (test_bit(daddr >> 2, pnd->addrs))
201 saddr = daddr;
202 else
203 saddr = find_first_bit(pnd->addrs, 64) << 2;
204 } else
205 saddr = PN_NO_ADDR;
206 rcu_read_unlock();
208 if (saddr == PN_NO_ADDR) {
209 /* Fallback to another device */
210 struct net_device *def_dev;
212 def_dev = phonet_device_get(dev_net(dev));
213 if (def_dev) {
214 if (def_dev != dev)
215 saddr = phonet_address_get(def_dev, daddr);
216 dev_put(def_dev);
219 return saddr;
222 int phonet_address_lookup(struct net *net, u8 addr)
224 struct phonet_device_list *pndevs = phonet_device_list(net);
225 struct phonet_device *pnd;
226 int err = -EADDRNOTAVAIL;
228 rcu_read_lock();
229 list_for_each_entry_rcu(pnd, &pndevs->list, list) {
230 /* Don't allow unregistering devices! */
231 if ((pnd->netdev->reg_state != NETREG_REGISTERED) ||
232 ((pnd->netdev->flags & IFF_UP)) != IFF_UP)
233 continue;
235 if (test_bit(addr >> 2, pnd->addrs)) {
236 err = 0;
237 goto found;
240 found:
241 rcu_read_unlock();
242 return err;
245 /* automatically configure a Phonet device, if supported */
246 static int phonet_device_autoconf(struct net_device *dev)
248 struct if_phonet_req req;
249 int ret;
251 if (!dev->netdev_ops->ndo_do_ioctl)
252 return -EOPNOTSUPP;
254 ret = dev->netdev_ops->ndo_do_ioctl(dev, (struct ifreq *)&req,
255 SIOCPNGAUTOCONF);
256 if (ret < 0)
257 return ret;
259 ASSERT_RTNL();
260 ret = phonet_address_add(dev, req.ifr_phonet_autoconf.device);
261 if (ret)
262 return ret;
263 phonet_address_notify(RTM_NEWADDR, dev,
264 req.ifr_phonet_autoconf.device);
265 return 0;
268 static void phonet_route_autodel(struct net_device *dev)
270 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
271 unsigned i;
272 DECLARE_BITMAP(deleted, 64);
274 /* Remove left-over Phonet routes */
275 bitmap_zero(deleted, 64);
276 mutex_lock(&pnn->routes.lock);
277 for (i = 0; i < 64; i++)
278 if (dev == pnn->routes.table[i]) {
279 rcu_assign_pointer(pnn->routes.table[i], NULL);
280 set_bit(i, deleted);
282 mutex_unlock(&pnn->routes.lock);
284 if (bitmap_empty(deleted, 64))
285 return; /* short-circuit RCU */
286 synchronize_rcu();
287 for_each_set_bit(i, deleted, 64) {
288 rtm_phonet_notify(RTM_DELROUTE, dev, i);
289 dev_put(dev);
293 /* notify Phonet of device events */
294 static int phonet_device_notify(struct notifier_block *me, unsigned long what,
295 void *arg)
297 struct net_device *dev = arg;
299 switch (what) {
300 case NETDEV_REGISTER:
301 if (dev->type == ARPHRD_PHONET)
302 phonet_device_autoconf(dev);
303 break;
304 case NETDEV_UNREGISTER:
305 phonet_device_destroy(dev);
306 phonet_route_autodel(dev);
307 break;
309 return 0;
313 static struct notifier_block phonet_device_notifier = {
314 .notifier_call = phonet_device_notify,
315 .priority = 0,
318 /* Per-namespace Phonet devices handling */
319 static int __net_init phonet_init_net(struct net *net)
321 struct phonet_net *pnn = phonet_pernet(net);
323 if (!proc_net_fops_create(net, "phonet", 0, &pn_sock_seq_fops))
324 return -ENOMEM;
326 INIT_LIST_HEAD(&pnn->pndevs.list);
327 mutex_init(&pnn->pndevs.lock);
328 mutex_init(&pnn->routes.lock);
329 return 0;
332 static void __net_exit phonet_exit_net(struct net *net)
334 struct phonet_net *pnn = phonet_pernet(net);
335 struct net_device *dev;
336 unsigned i;
338 rtnl_lock();
339 for_each_netdev(net, dev)
340 phonet_device_destroy(dev);
342 for (i = 0; i < 64; i++) {
343 dev = pnn->routes.table[i];
344 if (dev) {
345 rtm_phonet_notify(RTM_DELROUTE, dev, i);
346 dev_put(dev);
349 rtnl_unlock();
351 proc_net_remove(net, "phonet");
354 static struct pernet_operations phonet_net_ops = {
355 .init = phonet_init_net,
356 .exit = phonet_exit_net,
357 .id = &phonet_net_id,
358 .size = sizeof(struct phonet_net),
361 /* Initialize Phonet devices list */
362 int __init phonet_device_init(void)
364 int err = register_pernet_device(&phonet_net_ops);
365 if (err)
366 return err;
368 proc_net_fops_create(&init_net, "pnresource", 0, &pn_res_seq_fops);
369 register_netdevice_notifier(&phonet_device_notifier);
370 err = phonet_netlink_register();
371 if (err)
372 phonet_device_exit();
373 return err;
376 void phonet_device_exit(void)
378 rtnl_unregister_all(PF_PHONET);
379 unregister_netdevice_notifier(&phonet_device_notifier);
380 unregister_pernet_device(&phonet_net_ops);
381 proc_net_remove(&init_net, "pnresource");
384 int phonet_route_add(struct net_device *dev, u8 daddr)
386 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
387 struct phonet_routes *routes = &pnn->routes;
388 int err = -EEXIST;
390 daddr = daddr >> 2;
391 mutex_lock(&routes->lock);
392 if (routes->table[daddr] == NULL) {
393 rcu_assign_pointer(routes->table[daddr], dev);
394 dev_hold(dev);
395 err = 0;
397 mutex_unlock(&routes->lock);
398 return err;
401 int phonet_route_del(struct net_device *dev, u8 daddr)
403 struct phonet_net *pnn = phonet_pernet(dev_net(dev));
404 struct phonet_routes *routes = &pnn->routes;
406 daddr = daddr >> 2;
407 mutex_lock(&routes->lock);
408 if (dev == routes->table[daddr])
409 rcu_assign_pointer(routes->table[daddr], NULL);
410 else
411 dev = NULL;
412 mutex_unlock(&routes->lock);
414 if (!dev)
415 return -ENOENT;
416 synchronize_rcu();
417 dev_put(dev);
418 return 0;
421 struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr)
423 struct phonet_net *pnn = phonet_pernet(net);
424 struct phonet_routes *routes = &pnn->routes;
425 struct net_device *dev;
427 daddr >>= 2;
428 dev = rcu_dereference(routes->table[daddr]);
429 return dev;
432 struct net_device *phonet_route_output(struct net *net, u8 daddr)
434 struct phonet_net *pnn = phonet_pernet(net);
435 struct phonet_routes *routes = &pnn->routes;
436 struct net_device *dev;
438 daddr >>= 2;
439 rcu_read_lock();
440 dev = rcu_dereference(routes->table[daddr]);
441 if (dev)
442 dev_hold(dev);
443 rcu_read_unlock();
445 if (!dev)
446 dev = phonet_device_get(net); /* Default route */
447 return dev;