1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Linux WiMAX
4  * Initialization, addition and removal of wimax devices
5  *
6  * Copyright (C) 2005-2006 Intel Corporation <linux-wimax@intel.com>
7  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
8  *
9  * This implements:
10  *
11  *   - basic life cycle of 'struct wimax_dev' [wimax_dev_*()]; on
12  *     addition/registration initialize all subfields and allocate
13  *     generic netlink resources for user space communication. On
14  *     removal/unregistration, undo all that.
15  *
16  *   - device state machine [wimax_state_change()] and support to send
17  *     reports to user space when the state changes
18  *     [wimax_gnl_re_state_change*()].
19  *
20  * See include/net/wimax.h for rationales and design.
21  *
22  * ROADMAP
23  *
24  * [__]wimax_state_change()     Called by drivers to update device's state
25  *   wimax_gnl_re_state_change_alloc()
26  *   wimax_gnl_re_state_change_send()
27  *
28  * wimax_dev_init()	        Init a device
29  * wimax_dev_add()              Register
30  *   wimax_rfkill_add()
31  *   wimax_gnl_add()            Register all the generic netlink resources.
32  *   wimax_id_table_add()
33  * wimax_dev_rm()               Unregister
34  *   wimax_id_table_rm()
35  *   wimax_gnl_rm()
36  *   wimax_rfkill_rm()
37  */
38 #include <linux/device.h>
39 #include <linux/gfp.h>
40 #include <net/genetlink.h>
41 #include <linux/netdevice.h>
42 #include <linux/wimax.h>
43 #include <linux/module.h>
44 #include "wimax-internal.h"
45 
46 
47 #define D_SUBMODULE stack
48 #include "debug-levels.h"
49 
50 static char wimax_debug_params[128];
51 module_param_string(debug, wimax_debug_params, sizeof(wimax_debug_params),
52 		    0644);
53 MODULE_PARM_DESC(debug,
54 		 "String of space-separated NAME:VALUE pairs, where NAMEs "
55 		 "are the different debug submodules and VALUE are the "
56 		 "initial debug value to set.");
57 
58 /*
59  * Authoritative source for the RE_STATE_CHANGE attribute policy
60  *
61  * We don't really use it here, but /me likes to keep the definition
62  * close to where the data is generated.
63  */
64 /*
65 static const struct nla_policy wimax_gnl_re_status_change[WIMAX_GNL_ATTR_MAX + 1] = {
66 	[WIMAX_GNL_STCH_STATE_OLD] = { .type = NLA_U8 },
67 	[WIMAX_GNL_STCH_STATE_NEW] = { .type = NLA_U8 },
68 };
69 */
70 
71 
72 /*
73  * Allocate a Report State Change message
74  *
75  * @header: save it, you need it for _send()
76  *
77  * Creates and fills a basic state change message; different code
78  * paths can then add more attributes to the message as needed.
79  *
80  * Use wimax_gnl_re_state_change_send() to send the returned skb.
81  *
82  * Returns: skb with the genl message if ok, IS_ERR() ptr on error
83  *     with an errno code.
84  */
85 static
wimax_gnl_re_state_change_alloc(struct wimax_dev * wimax_dev,enum wimax_st new_state,enum wimax_st old_state,void ** header)86 struct sk_buff *wimax_gnl_re_state_change_alloc(
87 	struct wimax_dev *wimax_dev,
88 	enum wimax_st new_state, enum wimax_st old_state,
89 	void **header)
90 {
91 	int result;
92 	struct device *dev = wimax_dev_to_dev(wimax_dev);
93 	void *data;
94 	struct sk_buff *report_skb;
95 
96 	d_fnstart(3, dev, "(wimax_dev %p new_state %u old_state %u)\n",
97 		  wimax_dev, new_state, old_state);
98 	result = -ENOMEM;
99 	report_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
100 	if (report_skb == NULL) {
101 		dev_err(dev, "RE_STCH: can't create message\n");
102 		goto error_new;
103 	}
104 	/* FIXME: sending a group ID as the seq is wrong */
105 	data = genlmsg_put(report_skb, 0, wimax_gnl_family.mcgrp_offset,
106 			   &wimax_gnl_family, 0, WIMAX_GNL_RE_STATE_CHANGE);
107 	if (data == NULL) {
108 		dev_err(dev, "RE_STCH: can't put data into message\n");
109 		goto error_put;
110 	}
111 	*header = data;
112 
113 	result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_OLD, old_state);
114 	if (result < 0) {
115 		dev_err(dev, "RE_STCH: Error adding OLD attr: %d\n", result);
116 		goto error_put;
117 	}
118 	result = nla_put_u8(report_skb, WIMAX_GNL_STCH_STATE_NEW, new_state);
119 	if (result < 0) {
120 		dev_err(dev, "RE_STCH: Error adding NEW attr: %d\n", result);
121 		goto error_put;
122 	}
123 	result = nla_put_u32(report_skb, WIMAX_GNL_STCH_IFIDX,
124 			     wimax_dev->net_dev->ifindex);
125 	if (result < 0) {
126 		dev_err(dev, "RE_STCH: Error adding IFINDEX attribute\n");
127 		goto error_put;
128 	}
129 	d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %p\n",
130 		wimax_dev, new_state, old_state, report_skb);
131 	return report_skb;
132 
133 error_put:
134 	nlmsg_free(report_skb);
135 error_new:
136 	d_fnend(3, dev, "(wimax_dev %p new_state %u old_state %u) = %d\n",
137 		wimax_dev, new_state, old_state, result);
138 	return ERR_PTR(result);
139 }
140 
141 
142 /*
143  * Send a Report State Change message (as created with _alloc).
144  *
145  * @report_skb: as returned by wimax_gnl_re_state_change_alloc()
146  * @header: as returned by wimax_gnl_re_state_change_alloc()
147  *
148  * Returns: 0 if ok, < 0 errno code on error.
149  *
150  * If the message is  NULL, pretend it didn't happen.
151  */
152 static
wimax_gnl_re_state_change_send(struct wimax_dev * wimax_dev,struct sk_buff * report_skb,void * header)153 int wimax_gnl_re_state_change_send(
154 	struct wimax_dev *wimax_dev, struct sk_buff *report_skb,
155 	void *header)
156 {
157 	int result = 0;
158 	struct device *dev = wimax_dev_to_dev(wimax_dev);
159 	d_fnstart(3, dev, "(wimax_dev %p report_skb %p)\n",
160 		  wimax_dev, report_skb);
161 	if (report_skb == NULL) {
162 		result = -ENOMEM;
163 		goto out;
164 	}
165 	genlmsg_end(report_skb, header);
166 	genlmsg_multicast(&wimax_gnl_family, report_skb, 0, 0, GFP_KERNEL);
167 out:
168 	d_fnend(3, dev, "(wimax_dev %p report_skb %p) = %d\n",
169 		wimax_dev, report_skb, result);
170 	return result;
171 }
172 
173 
174 static
__check_new_state(enum wimax_st old_state,enum wimax_st new_state,unsigned int allowed_states_bm)175 void __check_new_state(enum wimax_st old_state, enum wimax_st new_state,
176 		       unsigned int allowed_states_bm)
177 {
178 	if (WARN_ON(((1 << new_state) & allowed_states_bm) == 0)) {
179 		pr_err("SW BUG! Forbidden state change %u -> %u\n",
180 		       old_state, new_state);
181 	}
182 }
183 
184 
185 /*
186  * Set the current state of a WiMAX device [unlocking version of
187  * wimax_state_change().
188  */
__wimax_state_change(struct wimax_dev * wimax_dev,enum wimax_st new_state)189 void __wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state)
190 {
191 	struct device *dev = wimax_dev_to_dev(wimax_dev);
192 	enum wimax_st old_state = wimax_dev->state;
193 	struct sk_buff *stch_skb;
194 	void *header;
195 
196 	d_fnstart(3, dev, "(wimax_dev %p new_state %u [old %u])\n",
197 		  wimax_dev, new_state, old_state);
198 
199 	if (WARN_ON(new_state >= __WIMAX_ST_INVALID)) {
200 		dev_err(dev, "SW BUG: requesting invalid state %u\n",
201 			new_state);
202 		goto out;
203 	}
204 	if (old_state == new_state)
205 		goto out;
206 	header = NULL;	/* gcc complains? can't grok why */
207 	stch_skb = wimax_gnl_re_state_change_alloc(
208 		wimax_dev, new_state, old_state, &header);
209 
210 	/* Verify the state transition and do exit-from-state actions */
211 	switch (old_state) {
212 	case __WIMAX_ST_NULL:
213 		__check_new_state(old_state, new_state,
214 				  1 << WIMAX_ST_DOWN);
215 		break;
216 	case WIMAX_ST_DOWN:
217 		__check_new_state(old_state, new_state,
218 				  1 << __WIMAX_ST_QUIESCING
219 				  | 1 << WIMAX_ST_UNINITIALIZED
220 				  | 1 << WIMAX_ST_RADIO_OFF);
221 		break;
222 	case __WIMAX_ST_QUIESCING:
223 		__check_new_state(old_state, new_state, 1 << WIMAX_ST_DOWN);
224 		break;
225 	case WIMAX_ST_UNINITIALIZED:
226 		__check_new_state(old_state, new_state,
227 				  1 << __WIMAX_ST_QUIESCING
228 				  | 1 << WIMAX_ST_RADIO_OFF);
229 		break;
230 	case WIMAX_ST_RADIO_OFF:
231 		__check_new_state(old_state, new_state,
232 				  1 << __WIMAX_ST_QUIESCING
233 				  | 1 << WIMAX_ST_READY);
234 		break;
235 	case WIMAX_ST_READY:
236 		__check_new_state(old_state, new_state,
237 				  1 << __WIMAX_ST_QUIESCING
238 				  | 1 << WIMAX_ST_RADIO_OFF
239 				  | 1 << WIMAX_ST_SCANNING
240 				  | 1 << WIMAX_ST_CONNECTING
241 				  | 1 << WIMAX_ST_CONNECTED);
242 		break;
243 	case WIMAX_ST_SCANNING:
244 		__check_new_state(old_state, new_state,
245 				  1 << __WIMAX_ST_QUIESCING
246 				  | 1 << WIMAX_ST_RADIO_OFF
247 				  | 1 << WIMAX_ST_READY
248 				  | 1 << WIMAX_ST_CONNECTING
249 				  | 1 << WIMAX_ST_CONNECTED);
250 		break;
251 	case WIMAX_ST_CONNECTING:
252 		__check_new_state(old_state, new_state,
253 				  1 << __WIMAX_ST_QUIESCING
254 				  | 1 << WIMAX_ST_RADIO_OFF
255 				  | 1 << WIMAX_ST_READY
256 				  | 1 << WIMAX_ST_SCANNING
257 				  | 1 << WIMAX_ST_CONNECTED);
258 		break;
259 	case WIMAX_ST_CONNECTED:
260 		__check_new_state(old_state, new_state,
261 				  1 << __WIMAX_ST_QUIESCING
262 				  | 1 << WIMAX_ST_RADIO_OFF
263 				  | 1 << WIMAX_ST_READY);
264 		netif_tx_disable(wimax_dev->net_dev);
265 		netif_carrier_off(wimax_dev->net_dev);
266 		break;
267 	case __WIMAX_ST_INVALID:
268 	default:
269 		dev_err(dev, "SW BUG: wimax_dev %p is in unknown state %u\n",
270 			wimax_dev, wimax_dev->state);
271 		WARN_ON(1);
272 		goto out;
273 	}
274 
275 	/* Execute the actions of entry to the new state */
276 	switch (new_state) {
277 	case __WIMAX_ST_NULL:
278 		dev_err(dev, "SW BUG: wimax_dev %p entering NULL state "
279 			"from %u\n", wimax_dev, wimax_dev->state);
280 		WARN_ON(1);		/* Nobody can enter this state */
281 		break;
282 	case WIMAX_ST_DOWN:
283 		break;
284 	case __WIMAX_ST_QUIESCING:
285 		break;
286 	case WIMAX_ST_UNINITIALIZED:
287 		break;
288 	case WIMAX_ST_RADIO_OFF:
289 		break;
290 	case WIMAX_ST_READY:
291 		break;
292 	case WIMAX_ST_SCANNING:
293 		break;
294 	case WIMAX_ST_CONNECTING:
295 		break;
296 	case WIMAX_ST_CONNECTED:
297 		netif_carrier_on(wimax_dev->net_dev);
298 		netif_wake_queue(wimax_dev->net_dev);
299 		break;
300 	case __WIMAX_ST_INVALID:
301 	default:
302 		BUG();
303 	}
304 	__wimax_state_set(wimax_dev, new_state);
305 	if (!IS_ERR(stch_skb))
306 		wimax_gnl_re_state_change_send(wimax_dev, stch_skb, header);
307 out:
308 	d_fnend(3, dev, "(wimax_dev %p new_state %u [old %u]) = void\n",
309 		wimax_dev, new_state, old_state);
310 }
311 
312 
313 /**
314  * wimax_state_change - Set the current state of a WiMAX device
315  *
316  * @wimax_dev: WiMAX device descriptor (properly referenced)
317  * @new_state: New state to switch to
318  *
319  * This implements the state changes for the wimax devices. It will
320  *
321  * - verify that the state transition is legal (for now it'll just
322  *   print a warning if not) according to the table in
323  *   linux/wimax.h's documentation for 'enum wimax_st'.
324  *
325  * - perform the actions needed for leaving the current state and
326  *   whichever are needed for entering the new state.
327  *
328  * - issue a report to user space indicating the new state (and an
329  *   optional payload with information about the new state).
330  *
331  * NOTE: @wimax_dev must be locked
332  */
wimax_state_change(struct wimax_dev * wimax_dev,enum wimax_st new_state)333 void wimax_state_change(struct wimax_dev *wimax_dev, enum wimax_st new_state)
334 {
335 	/*
336 	 * A driver cannot take the wimax_dev out of the
337 	 * __WIMAX_ST_NULL state unless by calling wimax_dev_add(). If
338 	 * the wimax_dev's state is still NULL, we ignore any request
339 	 * to change its state because it means it hasn't been yet
340 	 * registered.
341 	 *
342 	 * There is no need to complain about it, as routines that
343 	 * call this might be shared from different code paths that
344 	 * are called before or after wimax_dev_add() has done its
345 	 * job.
346 	 */
347 	mutex_lock(&wimax_dev->mutex);
348 	if (wimax_dev->state > __WIMAX_ST_NULL)
349 		__wimax_state_change(wimax_dev, new_state);
350 	mutex_unlock(&wimax_dev->mutex);
351 }
352 EXPORT_SYMBOL_GPL(wimax_state_change);
353 
354 
355 /**
356  * wimax_state_get() - Return the current state of a WiMAX device
357  *
358  * @wimax_dev: WiMAX device descriptor
359  *
360  * Returns: Current state of the device according to its driver.
361  */
wimax_state_get(struct wimax_dev * wimax_dev)362 enum wimax_st wimax_state_get(struct wimax_dev *wimax_dev)
363 {
364 	enum wimax_st state;
365 	mutex_lock(&wimax_dev->mutex);
366 	state = wimax_dev->state;
367 	mutex_unlock(&wimax_dev->mutex);
368 	return state;
369 }
370 EXPORT_SYMBOL_GPL(wimax_state_get);
371 
372 
373 /**
374  * wimax_dev_init - initialize a newly allocated instance
375  *
376  * @wimax_dev: WiMAX device descriptor to initialize.
377  *
378  * Initializes fields of a freshly allocated @wimax_dev instance. This
379  * function assumes that after allocation, the memory occupied by
380  * @wimax_dev was zeroed.
381  */
wimax_dev_init(struct wimax_dev * wimax_dev)382 void wimax_dev_init(struct wimax_dev *wimax_dev)
383 {
384 	INIT_LIST_HEAD(&wimax_dev->id_table_node);
385 	__wimax_state_set(wimax_dev, __WIMAX_ST_NULL);
386 	mutex_init(&wimax_dev->mutex);
387 	mutex_init(&wimax_dev->mutex_reset);
388 }
389 EXPORT_SYMBOL_GPL(wimax_dev_init);
390 
391 static const struct nla_policy wimax_gnl_policy[WIMAX_GNL_ATTR_MAX + 1] = {
392 	[WIMAX_GNL_RESET_IFIDX] = { .type = NLA_U32, },
393 	[WIMAX_GNL_RFKILL_IFIDX] = { .type = NLA_U32, },
394 	[WIMAX_GNL_RFKILL_STATE] = {
395 		.type = NLA_U32		/* enum wimax_rf_state */
396 	},
397 	[WIMAX_GNL_STGET_IFIDX] = { .type = NLA_U32, },
398 	[WIMAX_GNL_MSG_IFIDX] = { .type = NLA_U32, },
399 	[WIMAX_GNL_MSG_DATA] = {
400 		.type = NLA_UNSPEC,	/* libnl doesn't grok BINARY yet */
401 	},
402 };
403 
404 static const struct genl_small_ops wimax_gnl_ops[] = {
405 	{
406 		.cmd = WIMAX_GNL_OP_MSG_FROM_USER,
407 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
408 		.flags = GENL_ADMIN_PERM,
409 		.doit = wimax_gnl_doit_msg_from_user,
410 	},
411 	{
412 		.cmd = WIMAX_GNL_OP_RESET,
413 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
414 		.flags = GENL_ADMIN_PERM,
415 		.doit = wimax_gnl_doit_reset,
416 	},
417 	{
418 		.cmd = WIMAX_GNL_OP_RFKILL,
419 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
420 		.flags = GENL_ADMIN_PERM,
421 		.doit = wimax_gnl_doit_rfkill,
422 	},
423 	{
424 		.cmd = WIMAX_GNL_OP_STATE_GET,
425 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
426 		.flags = GENL_ADMIN_PERM,
427 		.doit = wimax_gnl_doit_state_get,
428 	},
429 };
430 
431 
432 static
wimax_addr_scnprint(char * addr_str,size_t addr_str_size,unsigned char * addr,size_t addr_len)433 size_t wimax_addr_scnprint(char *addr_str, size_t addr_str_size,
434 			   unsigned char *addr, size_t addr_len)
435 {
436 	unsigned int cnt, total;
437 
438 	for (total = cnt = 0; cnt < addr_len; cnt++)
439 		total += scnprintf(addr_str + total, addr_str_size - total,
440 				   "%02x%c", addr[cnt],
441 				   cnt == addr_len - 1 ? '\0' : ':');
442 	return total;
443 }
444 
445 
446 /**
447  * wimax_dev_add - Register a new WiMAX device
448  *
449  * @wimax_dev: WiMAX device descriptor (as embedded in your @net_dev's
450  *     priv data). You must have called wimax_dev_init() on it before.
451  *
452  * @net_dev: net device the @wimax_dev is associated with. The
453  *     function expects SET_NETDEV_DEV() and register_netdev() were
454  *     already called on it.
455  *
456  * Registers the new WiMAX device, sets up the user-kernel control
457  * interface (generic netlink) and common WiMAX infrastructure.
458  *
459  * Note that the parts that will allow interaction with user space are
460  * setup at the very end, when the rest is in place, as once that
461  * happens, the driver might get user space control requests via
462  * netlink or from debugfs that might translate into calls into
463  * wimax_dev->op_*().
464  */
wimax_dev_add(struct wimax_dev * wimax_dev,struct net_device * net_dev)465 int wimax_dev_add(struct wimax_dev *wimax_dev, struct net_device *net_dev)
466 {
467 	int result;
468 	struct device *dev = net_dev->dev.parent;
469 	char addr_str[32];
470 
471 	d_fnstart(3, dev, "(wimax_dev %p net_dev %p)\n", wimax_dev, net_dev);
472 
473 	/* Do the RFKILL setup before locking, as RFKILL will call
474 	 * into our functions.
475 	 */
476 	wimax_dev->net_dev = net_dev;
477 	result = wimax_rfkill_add(wimax_dev);
478 	if (result < 0)
479 		goto error_rfkill_add;
480 
481 	/* Set up user-space interaction */
482 	mutex_lock(&wimax_dev->mutex);
483 	wimax_id_table_add(wimax_dev);
484 	wimax_debugfs_add(wimax_dev);
485 
486 	__wimax_state_set(wimax_dev, WIMAX_ST_DOWN);
487 	mutex_unlock(&wimax_dev->mutex);
488 
489 	wimax_addr_scnprint(addr_str, sizeof(addr_str),
490 			    net_dev->dev_addr, net_dev->addr_len);
491 	dev_err(dev, "WiMAX interface %s (%s) ready\n",
492 		net_dev->name, addr_str);
493 	d_fnend(3, dev, "(wimax_dev %p net_dev %p) = 0\n", wimax_dev, net_dev);
494 	return 0;
495 
496 error_rfkill_add:
497 	d_fnend(3, dev, "(wimax_dev %p net_dev %p) = %d\n",
498 		wimax_dev, net_dev, result);
499 	return result;
500 }
501 EXPORT_SYMBOL_GPL(wimax_dev_add);
502 
503 
504 /**
505  * wimax_dev_rm - Unregister an existing WiMAX device
506  *
507  * @wimax_dev: WiMAX device descriptor
508  *
509  * Unregisters a WiMAX device previously registered for use with
510  * wimax_add_rm().
511  *
512  * IMPORTANT! Must call before calling unregister_netdev().
513  *
514  * After this function returns, you will not get any more user space
515  * control requests (via netlink or debugfs) and thus to wimax_dev->ops.
516  *
517  * Reentrancy control is ensured by setting the state to
518  * %__WIMAX_ST_QUIESCING. rfkill operations coming through
519  * wimax_*rfkill*() will be stopped by the quiescing state; ops coming
520  * from the rfkill subsystem will be stopped by the support being
521  * removed by wimax_rfkill_rm().
522  */
wimax_dev_rm(struct wimax_dev * wimax_dev)523 void wimax_dev_rm(struct wimax_dev *wimax_dev)
524 {
525 	d_fnstart(3, NULL, "(wimax_dev %p)\n", wimax_dev);
526 
527 	mutex_lock(&wimax_dev->mutex);
528 	__wimax_state_change(wimax_dev, __WIMAX_ST_QUIESCING);
529 	wimax_debugfs_rm(wimax_dev);
530 	wimax_id_table_rm(wimax_dev);
531 	__wimax_state_change(wimax_dev, WIMAX_ST_DOWN);
532 	mutex_unlock(&wimax_dev->mutex);
533 	wimax_rfkill_rm(wimax_dev);
534 	d_fnend(3, NULL, "(wimax_dev %p) = void\n", wimax_dev);
535 }
536 EXPORT_SYMBOL_GPL(wimax_dev_rm);
537 
538 
539 /* Debug framework control of debug levels */
540 struct d_level D_LEVEL[] = {
541 	D_SUBMODULE_DEFINE(debugfs),
542 	D_SUBMODULE_DEFINE(id_table),
543 	D_SUBMODULE_DEFINE(op_msg),
544 	D_SUBMODULE_DEFINE(op_reset),
545 	D_SUBMODULE_DEFINE(op_rfkill),
546 	D_SUBMODULE_DEFINE(op_state_get),
547 	D_SUBMODULE_DEFINE(stack),
548 };
549 size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
550 
551 
552 static const struct genl_multicast_group wimax_gnl_mcgrps[] = {
553 	{ .name = "msg", },
554 };
555 
556 struct genl_family wimax_gnl_family __ro_after_init = {
557 	.name = "WiMAX",
558 	.version = WIMAX_GNL_VERSION,
559 	.hdrsize = 0,
560 	.maxattr = WIMAX_GNL_ATTR_MAX,
561 	.policy = wimax_gnl_policy,
562 	.module = THIS_MODULE,
563 	.small_ops = wimax_gnl_ops,
564 	.n_small_ops = ARRAY_SIZE(wimax_gnl_ops),
565 	.mcgrps = wimax_gnl_mcgrps,
566 	.n_mcgrps = ARRAY_SIZE(wimax_gnl_mcgrps),
567 };
568 
569 
570 
571 /* Shutdown the wimax stack */
572 static
wimax_subsys_init(void)573 int __init wimax_subsys_init(void)
574 {
575 	int result;
576 
577 	d_fnstart(4, NULL, "()\n");
578 	d_parse_params(D_LEVEL, D_LEVEL_SIZE, wimax_debug_params,
579 		       "wimax.debug");
580 
581 	result = genl_register_family(&wimax_gnl_family);
582 	if (unlikely(result < 0)) {
583 		pr_err("cannot register generic netlink family: %d\n", result);
584 		goto error_register_family;
585 	}
586 
587 	d_fnend(4, NULL, "() = 0\n");
588 	return 0;
589 
590 error_register_family:
591 	d_fnend(4, NULL, "() = %d\n", result);
592 	return result;
593 
594 }
595 module_init(wimax_subsys_init);
596 
597 
598 /* Shutdown the wimax stack */
599 static
wimax_subsys_exit(void)600 void __exit wimax_subsys_exit(void)
601 {
602 	wimax_id_table_release();
603 	genl_unregister_family(&wimax_gnl_family);
604 }
605 module_exit(wimax_subsys_exit);
606 
607 MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>");
608 MODULE_DESCRIPTION("Linux WiMAX stack");
609 MODULE_LICENSE("GPL");
610