aboutsummaryrefslogtreecommitdiffstats
path: root/net/ieee802154/core.c
blob: 18bc7e7385074c4b62e5e7c87c1d2bba3981e7a4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
/*
 * Copyright (C) 2007, 2008, 2009 Siemens AG
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>

#include <net/cfg802154.h>
#include <net/rtnetlink.h>

#include "ieee802154.h"
#include "nl802154.h"
#include "sysfs.h"
#include "core.h"

/* RCU-protected (and RTNL for writers) */
LIST_HEAD(cfg802154_rdev_list);
int cfg802154_rdev_list_generation;

static int wpan_phy_match(struct device *dev, const void *data)
{
	return !strcmp(dev_name(dev), (const char *)data);
}

struct wpan_phy *wpan_phy_find(const char *str)
{
	struct device *dev;

	if (WARN_ON(!str))
		return NULL;

	dev = class_find_device(&wpan_phy_class, NULL, str, wpan_phy_match);
	if (!dev)
		return NULL;

	return container_of(dev, struct wpan_phy, dev);
}
EXPORT_SYMBOL(wpan_phy_find);

struct wpan_phy_iter_data {
	int (*fn)(struct wpan_phy *phy, void *data);
	void *data;
};

static int wpan_phy_iter(struct device *dev, void *_data)
{
	struct wpan_phy_iter_data *wpid = _data;
	struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);

	return wpid->fn(phy, wpid->data);
}

int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data),
		      void *data)
{
	struct wpan_phy_iter_data wpid = {
		.fn = fn,
		.data = data,
	};

	return class_for_each_device(&wpan_phy_class, NULL,
			&wpid, wpan_phy_iter);
}
EXPORT_SYMBOL(wpan_phy_for_each);

struct cfg802154_registered_device *
cfg802154_rdev_by_wpan_phy_idx(int wpan_phy_idx)
{
	struct cfg802154_registered_device *result = NULL, *rdev;

	ASSERT_RTNL();

	list_for_each_entry(rdev, &cfg802154_rdev_list, list) {
		if (rdev->wpan_phy_idx == wpan_phy_idx) {
			result = rdev;
			break;
		}
	}

	return result;
}

struct wpan_phy *
wpan_phy_new(const struct cfg802154_ops *ops, size_t priv_size)
{
	static atomic_t wpan_phy_counter = ATOMIC_INIT(0);
	struct cfg802154_registered_device *rdev;
	size_t alloc_size;

	alloc_size = sizeof(*rdev) + priv_size;
	rdev = kzalloc(alloc_size, GFP_KERNEL);
	if (!rdev)
		return NULL;

	rdev->ops = ops;

	rdev->wpan_phy_idx = atomic_inc_return(&wpan_phy_counter);

	if (unlikely(rdev->wpan_phy_idx < 0)) {
		/* ugh, wrapped! */
		atomic_dec(&wpan_phy_counter);
		kfree(rdev);
		return NULL;
	}

	/* atomic_inc_return makes it start at 1, make it start at 0 */
	rdev->wpan_phy_idx--;

	mutex_init(&rdev->wpan_phy.pib_lock);

	INIT_LIST_HEAD(&rdev->wpan_dev_list);
	device_initialize(&rdev->wpan_phy.dev);
	dev_set_name(&rdev->wpan_phy.dev, "wpan-phy%d", rdev->wpan_phy_idx);

	rdev->wpan_phy.dev.class = &wpan_phy_class;
	rdev->wpan_phy.dev.platform_data = rdev;

	init_waitqueue_head(&rdev->dev_wait);

	return &rdev->wpan_phy;
}
EXPORT_SYMBOL(wpan_phy_new);

int wpan_phy_register(struct wpan_phy *phy)
{
	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);
	int ret;

	rtnl_lock();
	ret = device_add(&phy->dev);
	if (ret) {
		rtnl_unlock();
		return ret;
	}

	list_add_rcu(&rdev->list, &cfg802154_rdev_list);
	cfg802154_rdev_list_generation++;

	/* TODO phy registered lock */
	rtnl_unlock();

	/* TODO nl802154 phy notify */

	return 0;
}
EXPORT_SYMBOL(wpan_phy_register);

void wpan_phy_unregister(struct wpan_phy *phy)
{
	struct cfg802154_registered_device *rdev = wpan_phy_to_rdev(phy);

	wait_event(rdev->dev_wait, ({
		int __count;
		rtnl_lock();
		__count = rdev->opencount;
		rtnl_unlock();
		__count == 0; }));

	rtnl_lock();
	/* TODO nl802154 phy notify */
	/* TODO phy registered lock */

	WARN_ON(!list_empty(&rdev->wpan_dev_list));

	/* First remove the hardware from everywhere, this makes
	 * it impossible to find from userspace.
	 */
	list_del_rcu(&rdev->list);
	synchronize_rcu();

	cfg802154_rdev_list_generation++;

	device_del(&phy->dev);

	rtnl_unlock();
}
EXPORT_SYMBOL(wpan_phy_unregister);

void wpan_phy_free(struct wpan_phy *phy)
{
	put_device(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_free);

void cfg802154_dev_free(struct cfg802154_registered_device *rdev)
{
	kfree(rdev);
}

static void
cfg802154_update_iface_num(struct cfg802154_registered_device *rdev,
			   int iftype, int num)
{
	ASSERT_RTNL();

	rdev->num_running_ifaces += num;
}

static int cfg802154_netdev_notifier_call(struct notifier_block *nb,
					  unsigned long state, void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	struct wpan_dev *wpan_dev = dev->ieee802154_ptr;
	struct cfg802154_registered_device *rdev;

	if (!wpan_dev)
		return NOTIFY_DONE;

	rdev = wpan_phy_to_rdev(wpan_dev->wpan_phy);

	/* TODO WARN_ON unspec type */

	switch (state) {
		/* TODO NETDEV_DEVTYPE */
	case NETDEV_REGISTER:
		wpan_dev->identifier = ++rdev->wpan_dev_id;
		list_add_rcu(&wpan_dev->list, &rdev->wpan_dev_list);
		rdev->devlist_generation++;

		wpan_dev->netdev = dev;
		break;
	case NETDEV_DOWN:
		cfg802154_update_iface_num(rdev, wpan_dev->iftype, -1);

		rdev->opencount--;
		wake_up(&rdev->dev_wait);
		break;
	case NETDEV_UP:
		cfg802154_update_iface_num(rdev, wpan_dev->iftype, 1);

		rdev->opencount++;
		break;
	case NETDEV_UNREGISTER:
		/* It is possible to get NETDEV_UNREGISTER
		 * multiple times. To detect that, check
		 * that the interface is still on the list
		 * of registered interfaces, and only then
		 * remove and clean it up.
		 */
		if (!list_empty(&wpan_dev->list)) {
			list_del_rcu(&wpan_dev->list);
			rdev->devlist_generation++;
		}
		/* synchronize (so that we won't find this netdev
		 * from other code any more) and then clear the list
		 * head so that the above code can safely check for
		 * !list_empty() to avoid double-cleanup.
		 */
		synchronize_rcu();
		INIT_LIST_HEAD(&wpan_dev->list);
		break;
	default:
		return NOTIFY_DONE;
	}

	return NOTIFY_OK;
}

static struct notifier_block cfg802154_netdev_notifier = {
	.notifier_call = cfg802154_netdev_notifier_call,
};

static int __init wpan_phy_class_init(void)
{
	int rc;

	rc = wpan_phy_sysfs_init();
	if (rc)
		goto err;

	rc = register_netdevice_notifier(&cfg802154_netdev_notifier);
	if (rc)
		goto err_nl;

	rc = ieee802154_nl_init();
	if (rc)
		goto err_notifier;

	rc = nl802154_init();
	if (rc)
		goto err_ieee802154_nl;

	return 0;

err_ieee802154_nl:
	ieee802154_nl_exit();

err_notifier:
	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
err_nl:
	wpan_phy_sysfs_exit();
err:
	return rc;
}
subsys_initcall(wpan_phy_class_init);

static void __exit wpan_phy_class_exit(void)
{
	nl802154_exit();
	ieee802154_nl_exit();
	unregister_netdevice_notifier(&cfg802154_netdev_notifier);
	wpan_phy_sysfs_exit();
}
module_exit(wpan_phy_class_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("IEEE 802.15.4 configuration interface");
MODULE_AUTHOR("Dmitry Eremin-Solenikov");