summaryrefslogtreecommitdiffstats
path: root/net/wimax/stack.c
blob: ee99e7dfcdbaa2a87d81d9044e0c30690013e45d (plain)
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
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
/*
 * Linux WiMAX
 * Initialization, addition and removal of wimax devices
 *
 *
 * Copyright (C) 2005-2006 Intel Corporation <linux-wimax@intel.com>
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 *
 * This implements:
 *
 *   - basic life cycle of 'struct wimax_dev' [wimax_dev_*()]; on
 *     addition/registration initialize all subfields and allocate
 *     generic netlink resources for user space communication. On
 *     removal/unregistration, undo all that.
 *
 *   - device state machine [wimax_state_change()] and support to send
 *     reports to user space when the state changes
 *     [wimax_gnl_re_state_change*()].
 *
 * See include/net/wimax.h for rationales and design.
 *
 * ROADMAP
 *
 * [__]wimax_state_change()     Called by drivers to update device's state
 *   wimax_gnl_re_state_change_alloc()
 *   wimax_gnl_re_state_change_send()
 *
 * wimax_dev_init()	        Init a device
 * wimax_dev_add()              Register
 *   wimax_rfkill_add()
 *   wimax_gnl_add()            Register all the generic netlink resources.
 *   wimax_id_table_add()
 * wimax_dev_rm()               Unregister
 *   wimax_id_table_rm()
 *   wimax_gnl_rm()
 *   wimax_rfkill_rm()
 */
#include <linux/device.h>
#include <linux/gfp.h>
#include <net/genetlink.h>
#include <linux/netdevice.h>
#include <linux/wimax.h>
#include "wimax-internal.h"


#define D_SUBMODULE stack
#include "debug-levels.h"

static char wimax_debug_params[128];
module_param_string(debug, wimax_debug_params, sizeof(wimax_debug_params),
		    0644);
MODULE_PARM_DESC(debug,
		 "String of space-separated NAME:VALUE pairs, where NAMEs "
		 "are the different debug submodules and VALUE are the "
		 "initial debug value to set.");

/*
 * Authoritative source for the RE_STATE_CHANGE attribute policy
 *
 * We don't really use it here, but /me likes to keep the definition
 * close to where the data is generated.
 */
/*
static const struct nla_policy wimax_gnl_re_status_change[WIMAX_GNL_ATTR_MAX + 1] = {
	[WIMAX_GNL_STCH_STATE_OLD] = { .type = NLA_U8 },
	[WIMAX_GNL_STCH_STATE_NEW] = { .type = NLA_U8 },
};
*/


/*
 * Allocate a Report State Change message
 *
 * @header: save it, you need it for _send()
 *
 * Creates and fills a basic state change message; different code
 * paths can then add more attributes to the message as needed.
 *
 * Use wimax_gnl_re_state_change_send() to send the returned skb.
 *
 * Returns: skb with the genl message if ok, IS_ERR() ptr on error
 *     with an errno code.
 */
static
struct sk_buff *wimax_gnl_re_state_change_alloc(
	struct wimax_dev *wimax_dev,
	enum wimax_st new_state, enum wimax_st old_state,
	void **header)
{
	int result;
	struct device *dev = wimax_dev_to_dev(wimax_dev);
	void *data;
	struct sk_buff *report_skb;

	d_fnstart(3, dev, "(wimax_dev %p new_state %u old_state %u)\n",
		  wimax_dev, new_state, old_state);
	result = -ENOMEM;
	report_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
	if (report_skb == NULL) {
		dev_err(dev, "RE_STCH: can't create message\n");
		goto error_new;
	}
	data = genlmsg_put(report_skb, 0, wimax_gnl_mcg.id, &wimax_gnl_family,
			   0, WIMAX_GNL_RE_STATE_CHANGE);
	if (data == NULL) {
		dev_err(dev, "RE_STCH: can't put data into message\n");
		goto error_put;
	}
	*header = data;

	result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_OLD, old_state);
	if (result < 0) {
		dev_err(dev, "RE_STCH: Error adding OLD attr: %d\n", result);
		goto error_put;
	}
	result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_NEW, new_state);
	if (result < 0) {
		dev_err(dev, "RE_STCH: Error adding NEW attr: %d\n", result);
		goto error_put;
	}
	result = nla_put_u32(report_skb, WIMAX_GNL_STCH_IFIDX,
			     wimax_dev->net_dev->ifindex);
	if (result < 0) {
		dev_err(dev, "RE_STCH: Error adding IFINDEX attribute\n");
		goto error_put;
	}
	d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %p\n",
		wimax_dev, new_state, old_state, report_skb);
	return report_skb;

error_put:
	nlmsg_free(report_skb);
error_new:
	d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %d\n",
		wimax_dev, new_state, old_state, result);
	return ERR_PTR(result);
}


/*
 * Send a Report State Change message (as created with _alloc).
 *
 * @report_skb: as returned by wimax_gnl_re_state_change_alloc()
 * @header: as returned by wimax_gnl_re_state_change_alloc()
 *
 * Returns: 0 if ok, < 0 errno code on error.
 *
 * If the message is  NULL, pretend it didn't happen.
 */
static
int wimax_gnl_re_state_change_send(
	struct wimax_dev *wimax_dev, struct sk_buff *report_skb,
	void *header)
{
	int result = 0;
	struct device *dev = wimax_dev_to_dev(wimax_dev);
	d_fnstart(3, dev, "(wimax_dev %p report_skb %p)\n",
		  wimax_dev, report_skb);
	if (report_skb == NULL) {
		result = -ENOMEM;
		goto out;
	}
	genlmsg_end(report_skb, header);
	genlmsg_multicast(report_skb, 0, wimax_gnl_mcg.id, GFP_KERNEL);
out:
	d_fnend(3, dev, "(wimax_dev %p report_skb %p) = %d\n",
		wimax_dev, report_skb, result);
	return result;
}


static
void __check_new_state(enum wimax_st old_state, enum wimax_st new_state,
		       unsigned allowed_states_bm)
{
	if (WARN_ON(((1 << new_state) & allowed_states_bm) == 0)) {
		printk(KERN_ERR "SW BUG! Forbidden state change %u -> %u\n",
			old_state, new_state);
	}
}


/*
 * Set the current state of a WiMAX device [unlocking version of
 * wimax_state_change().
 */
void __wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state)
{
	struct device *dev = wimax_dev_to_dev(wimax_dev);
	enum wimax_st old_state = wimax_dev->state;
	struct sk_buff *stch_skb;
	void *header;

	d_fnstart(3, dev, "(wimax_dev %p new_state %u [old %u])\n",
		  wimax_dev, new_state, old_state);

	if (WARN_ON(new_state >= __WIMAX_ST_INVALID)) {
		dev_err(dev, "SW BUG: requesting invalid state %u\n",
			new_state);
		goto out;
	}
	if (old_state == new_state)
		goto out;
	header = NULL;	/* gcc complains? can't grok why */
	stch_skb = wimax_gnl_re_state_change_alloc(
		wimax_dev, new_state, old_state, &header);

	/* Verify the state transition and do exit-from-state actions */
	switch (old_state) {
	case __WIMAX_ST_NULL:
		__check_new_state(old_state, new_state,
				  1 << WIMAX_ST_DOWN);
		break;
	case WIMAX_ST_DOWN:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_UNINITIALIZED
				  | 1 << WIMAX_ST_RADIO_OFF);
		break;
	case __WIMAX_ST_QUIESCING:
		__check_new_state(old_state, new_state, 1 << WIMAX_ST_DOWN);
		break;
	case WIMAX_ST_UNINITIALIZED:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_RADIO_OFF);
		break;
	case WIMAX_ST_RADIO_OFF:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_READY);
		break;
	case WIMAX_ST_READY:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_RADIO_OFF
				  | 1 << WIMAX_ST_SCANNING
				  | 1 << WIMAX_ST_CONNECTING
				  | 1 << WIMAX_ST_CONNECTED);
		break;
	case WIMAX_ST_SCANNING:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_RADIO_OFF
				  | 1 << WIMAX_ST_READY
				  | 1 << WIMAX_ST_CONNECTING
				  | 1 << WIMAX_ST_CONNECTED);
		break;
	case WIMAX_ST_CONNECTING:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_RADIO_OFF
				  | 1 << WIMAX_ST_READY
				  | 1 << WIMAX_ST_SCANNING
				  | 1 << WIMAX_ST_CONNECTED);
		break;
	case WIMAX_ST_CONNECTED:
		__check_new_state(old_state, new_state,
				  1 << __WIMAX_ST_QUIESCING
				  | 1 << WIMAX_ST_RADIO_OFF
				  | 1 << WIMAX_ST_READY);
		netif_tx_disable(wimax_dev->net_dev);
		netif_carrier_off(wimax_dev->net_dev);
		break;
	case __WIMAX_ST_INVALID:
	default:
		dev_err(dev, "SW BUG: wimax_dev %p is in unknown state %u\n",
			wimax_dev, wimax_dev->state);
		WARN_ON(1);
		goto out;
	}

	/* Execute the actions of entry to the new state */
	switch (new_state) {
	case __WIMAX_ST_NULL:
		dev_err(dev, "SW BUG: wimax_dev %p entering NULL state "
			"from %u\n", wimax_dev, wimax_dev->state);
		WARN_ON(1);		/* Nobody can enter this state */
		break;
	case WIMAX_ST_DOWN:
		break;
	case __WIMAX_ST_QUIESCING:
		break;
	case WIMAX_ST_UNINITIALIZED:
		break;
	case WIMAX_ST_RADIO_OFF:
		break;
	case WIMAX_ST_READY:
		break;
	case WIMAX_ST_SCANNING:
		break;
	case WIMAX_ST_CONNECTING:
		break;
	case WIMAX_ST_CONNECTED:
		netif_carrier_on(wimax_dev->net_dev);
		netif_wake_queue(wimax_dev->net_dev);
		break;
	case __WIMAX_ST_INVALID:
	default:
		BUG();
	}
	__wimax_state_set(wimax_dev, new_state);
	if (!IS_ERR(stch_skb))
		wimax_gnl_re_state_change_send(wimax_dev, stch_skb, header);
out:
	d_fnend(3, dev, "(wimax_dev %p new_state %u [old %u]) = void\n",
		wimax_dev, new_state, old_state);
}


/**
 * wimax_state_change - Set the current state of a WiMAX device
 *
 * @wimax_dev: WiMAX device descriptor (properly referenced)
 * @new_state: New state to switch to
 *
 * This implements the state changes for the wimax devices. It will
 *
 * - verify that the state transition is legal (for now it'll just
 *   print a warning if not) according to the table in
 *   linux/wimax.h's documentation for 'enum wimax_st'.
 *
 * - perform the actions needed for leaving the current state and
 *   whichever are needed for entering the new state.
 *
 * - issue a report to user space indicating the new state (and an
 *   optional payload with information about the new state).
 *
 * NOTE: @wimax_dev must be locked
 */
void wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state)
{
	/*
	 * A driver cannot take the wimax_dev out of the
	 * __WIMAX_ST_NULL state unless by calling wimax_dev_add(). If
	 * the wimax_dev's state is still NULL, we ignore any request
	 * to change its state because it means it hasn't been yet
	 * registered.
	 *
	 * There is no need to complain about it, as routines that
	 * call this might be shared from different code paths that
	 * are called before or after wimax_dev_add() has done its
	 * job.
	 */
	mutex_lock(&wimax_dev->mutex);
	if (wimax_dev->state > __WIMAX_ST_NULL)
		__wimax_state_change(wimax_dev, new_state);
	mutex_unlock(&wimax_dev->mutex);
}
EXPORT_SYMBOL_GPL(wimax_state_change);


/**
 * wimax_state_get() - Return the current state of a WiMAX device
 *
 * @wimax_dev: WiMAX device descriptor
 *
 * Returns: Current state of the device according to its driver.
 */
enum wimax_st wimax_state_get(struct wimax_dev *wimax_dev)
{
	enum wimax_st state;
	mutex_lock(&wimax_dev->mutex);
	state = wimax_dev->state;
	mutex_unlock(&wimax_dev->mutex);
	return state;
}
EXPORT_SYMBOL_GPL(wimax_state_get);


/**
 * wimax_dev_init - initialize a newly allocated instance
 *
 * @wimax_dev: WiMAX device descriptor to initialize.
 *
 * Initializes fields of a freshly allocated @wimax_dev instance. This
 * function assumes that after allocation, the memory occupied by
 * @wimax_dev was zeroed.
 */
void wimax_dev_init(struct wimax_dev *wimax_dev)
{
	INIT_LIST_HEAD(&wimax_dev->id_table_node);
	__wimax_state_set(wimax_dev, __WIMAX_ST_NULL);
	mutex_init(&wimax_dev->mutex);
	mutex_init(&wimax_dev->mutex_reset);
}
EXPORT_SYMBOL_GPL(wimax_dev_init);

/*
 * This extern is declared here because it's easier to keep track --
 * both declarations are a list of the same
 */
extern struct genl_ops
	wimax_gnl_msg_from_user,
	wimax_gnl_reset,
	wimax_gnl_rfkill,
	wimax_gnl_state_get;

static
struct genl_ops *wimax_gnl_ops[] = {
	&wimax_gnl_msg_from_user,
	&wimax_gnl_reset,
	&wimax_gnl_rfkill,
	&wimax_gnl_state_get,
};


static
size_t wimax_addr_scnprint(char *addr_str, size_t addr_str_size,
			   unsigned char *addr, size_t addr_len)
{
	unsigned cnt, total;
	for (total = cnt = 0; cnt < addr_len; cnt++)
		total += scnprintf(addr_str + total, addr_str_size - total,
				   "%02x%c", addr[cnt],
				   cnt == addr_len - 1 ? '\0' : ':');
	return total;
}


/**
 * wimax_dev_add - Register a new WiMAX device
 *
 * @wimax_dev: WiMAX device descriptor (as embedded in your @net_dev's
 *     priv data). You must have called wimax_dev_init() on it before.
 *
 * @net_dev: net device the @wimax_dev is associated with. The
 *     function expects SET_NETDEV_DEV() and register_netdev() were
 *     already called on it.
 *
 * Registers the new WiMAX device, sets up the user-kernel control
 * interface (generic netlink) and common WiMAX infrastructure.
 *
 * Note that the parts that will allow interaction with user space are
 * setup at the very end, when the rest is in place, as once that
 * happens, the driver might get user space control requests via
 * netlink or from debugfs that might translate into calls into
 * wimax_dev->op_*().
 */
int wimax_dev_add(struct wimax_dev *wimax_dev, struct net_device *net_dev)
{
	int result;
	struct device *dev = net_dev->dev.parent;
	char addr_str[32];

	d_fnstart(3, dev, "(wimax_dev %p net_dev %p)\n", wimax_dev, net_dev);

	/* Do the RFKILL setup before locking, as RFKILL will call
	 * into our functions. */
	wimax_dev->net_dev = net_dev;
	result = wimax_rfkill_add(wimax_dev);
	if (result < 0)
		goto error_rfkill_add;

	/* Set up user-space interaction */
	mutex_lock(&wimax_dev->mutex);
	wimax_id_table_add(wimax_dev);
	result = wimax_debugfs_add(wimax_dev);
	if (result < 0) {
		dev_err(dev, "cannot initialize debugfs: %d\n",
			result);
		goto error_debugfs_add;
	}

	__wimax_state_set(wimax_dev, WIMAX_ST_DOWN);
	mutex_unlock(&wimax_dev->mutex);

	wimax_addr_scnprint(addr_str, sizeof(addr_str),
			    net_dev->dev_addr, net_dev->addr_len);
	dev_err(dev, "WiMAX interface %s (%s) ready\n",
		net_dev->name, addr_str);
	d_fnend(3, dev, "(wimax_dev %p net_dev %p) = 0\n", wimax_dev, net_dev);
	return 0;

error_debugfs_add:
	wimax_id_table_rm(wimax_dev);
	mutex_unlock(&wimax_dev->mutex);
	wimax_rfkill_rm(wimax_dev);
error_rfkill_add:
	d_fnend(3, dev, "(wimax_dev %p net_dev %p) = %d\n",
		wimax_dev, net_dev, result);
	return result;
}
EXPORT_SYMBOL_GPL(wimax_dev_add);


/**
 * wimax_dev_rm - Unregister an existing WiMAX device
 *
 * @wimax_dev: WiMAX device descriptor
 *
 * Unregisters a WiMAX device previously registered for use with
 * wimax_add_rm().
 *
 * IMPORTANT! Must call before calling unregister_netdev().
 *
 * After this function returns, you will not get any more user space
 * control requests (via netlink or debugfs) and thus to wimax_dev->ops.
 *
 * Reentrancy control is ensured by setting the state to
 * %__WIMAX_ST_QUIESCING. rfkill operations coming through
 * wimax_*rfkill*() will be stopped by the quiescing state; ops coming
 * from the rfkill subsystem will be stopped by the support being
 * removed by wimax_rfkill_rm().
 */
void wimax_dev_rm(struct wimax_dev *wimax_dev)
{
	d_fnstart(3, NULL, "(wimax_dev %p)\n", wimax_dev);

	mutex_lock(&wimax_dev->mutex);
	__wimax_state_change(wimax_dev, __WIMAX_ST_QUIESCING);
	wimax_debugfs_rm(wimax_dev);
	wimax_id_table_rm(wimax_dev);
	__wimax_state_change(wimax_dev, WIMAX_ST_DOWN);
	mutex_unlock(&wimax_dev->mutex);
	wimax_rfkill_rm(wimax_dev);
	d_fnend(3, NULL, "(wimax_dev %p) = void\n", wimax_dev);
}
EXPORT_SYMBOL_GPL(wimax_dev_rm);


/* Debug framework control of debug levels */
struct d_level D_LEVEL[] = {
	D_SUBMODULE_DEFINE(debugfs),
	D_SUBMODULE_DEFINE(id_table),
	D_SUBMODULE_DEFINE(op_msg),
	D_SUBMODULE_DEFINE(op_reset),
	D_SUBMODULE_DEFINE(op_rfkill),
	D_SUBMODULE_DEFINE(op_state_get),
	D_SUBMODULE_DEFINE(stack),
};
size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);


struct genl_family wimax_gnl_family = {
	.id = GENL_ID_GENERATE,
	.name = "WiMAX",
	.version = WIMAX_GNL_VERSION,
	.hdrsize = 0,
	.maxattr = WIMAX_GNL_ATTR_MAX,
};

struct genl_multicast_group wimax_gnl_mcg = {
	.name = "msg",
};



/* Shutdown the wimax stack */
static
int __init wimax_subsys_init(void)
{
	int result, cnt;

	d_fnstart(4, NULL, "()\n");
	d_parse_params(D_LEVEL, D_LEVEL_SIZE, wimax_debug_params,
		       "wimax.debug");

	snprintf(wimax_gnl_family.name, sizeof(wimax_gnl_family.name),
		 "WiMAX");
	result = genl_register_family(&wimax_gnl_family);
	if (unlikely(result < 0)) {
		printk(KERN_ERR "cannot register generic netlink family: %d\n",
		       result);
		goto error_register_family;
	}

	for (cnt = 0; cnt < ARRAY_SIZE(wimax_gnl_ops); cnt++) {
		result = genl_register_ops(&wimax_gnl_family,
					   wimax_gnl_ops[cnt]);
		d_printf(4, NULL, "registering generic netlink op code "
			 "%u: %d\n", wimax_gnl_ops[cnt]->cmd, result);
		if (unlikely(result < 0)) {
			printk(KERN_ERR "cannot register generic netlink op "
			       "code %u: %d\n",
			       wimax_gnl_ops[cnt]->cmd, result);
			goto error_register_ops;
		}
	}

	result = genl_register_mc_group(&wimax_gnl_family, &wimax_gnl_mcg);
	if (result < 0)
		goto error_mc_group;
	d_fnend(4, NULL, "() = 0\n");
	return 0;

error_mc_group:
error_register_ops:
	for (cnt--; cnt >= 0; cnt--)
		genl_unregister_ops(&wimax_gnl_family,
				    wimax_gnl_ops[cnt]);
	genl_unregister_family(&wimax_gnl_family);
error_register_family:
	d_fnend(4, NULL, "() = %d\n", result);
	return result;

}
module_init(wimax_subsys_init);


/* Shutdown the wimax stack */
static
void __exit wimax_subsys_exit(void)
{
	int cnt;
	wimax_id_table_release();
	genl_unregister_mc_group(&wimax_gnl_family, &wimax_gnl_mcg);
	for (cnt = ARRAY_SIZE(wimax_gnl_ops) - 1; cnt >= 0; cnt--)
		genl_unregister_ops(&wimax_gnl_family,
				    wimax_gnl_ops[cnt]);
	genl_unregister_family(&wimax_gnl_family);
}
module_exit(wimax_subsys_exit);

MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>");
MODULE_DESCRIPTION("Linux WiMAX stack");
MODULE_LICENSE("GPL");