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  1// SPDX-License-Identifier: GPL-2.0
  2/* drivers/net/wireless/virt_wifi.c
  3 *
  4 * A fake implementation of cfg80211_ops that can be tacked on to an ethernet
  5 * net_device to make it appear as a wireless connection.
  6 *
  7 * Copyright (C) 2018 Google, Inc.
  8 *
  9 * Author: schuffelen@google.com
 10 */
 11
 12#include <net/cfg80211.h>
 13#include <net/rtnetlink.h>
 14#include <linux/etherdevice.h>
 15#include <linux/math64.h>
 16#include <linux/module.h>
 17
 18static struct wiphy *common_wiphy;
 19
 20struct virt_wifi_wiphy_priv {
 21	struct delayed_work scan_result;
 22	struct cfg80211_scan_request *scan_request;
 23	bool being_deleted;
 24};
 25
 26static struct ieee80211_channel channel_2ghz = {
 27	.band = NL80211_BAND_2GHZ,
 28	.center_freq = 2432,
 29	.hw_value = 2432,
 30	.max_power = 20,
 31};
 32
 33static struct ieee80211_rate bitrates_2ghz[] = {
 34	{ .bitrate = 10 },
 35	{ .bitrate = 20 },
 36	{ .bitrate = 55 },
 37	{ .bitrate = 110 },
 38	{ .bitrate = 60 },
 39	{ .bitrate = 120 },
 40	{ .bitrate = 240 },
 41};
 42
 43static struct ieee80211_supported_band band_2ghz = {
 44	.channels = &channel_2ghz,
 45	.bitrates = bitrates_2ghz,
 46	.band = NL80211_BAND_2GHZ,
 47	.n_channels = 1,
 48	.n_bitrates = ARRAY_SIZE(bitrates_2ghz),
 49	.ht_cap = {
 50		.ht_supported = true,
 51		.cap = IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
 52		       IEEE80211_HT_CAP_GRN_FLD |
 53		       IEEE80211_HT_CAP_SGI_20 |
 54		       IEEE80211_HT_CAP_SGI_40 |
 55		       IEEE80211_HT_CAP_DSSSCCK40,
 56		.ampdu_factor = 0x3,
 57		.ampdu_density = 0x6,
 58		.mcs = {
 59			.rx_mask = {0xff, 0xff},
 60			.tx_params = IEEE80211_HT_MCS_TX_DEFINED,
 61		},
 62	},
 63};
 64
 65static struct ieee80211_channel channel_5ghz = {
 66	.band = NL80211_BAND_5GHZ,
 67	.center_freq = 5240,
 68	.hw_value = 5240,
 69	.max_power = 20,
 70};
 71
 72static struct ieee80211_rate bitrates_5ghz[] = {
 73	{ .bitrate = 60 },
 74	{ .bitrate = 120 },
 75	{ .bitrate = 240 },
 76};
 77
 78#define RX_MCS_MAP (IEEE80211_VHT_MCS_SUPPORT_0_9 << 0 | \
 79		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 2 | \
 80		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 4 | \
 81		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 6 | \
 82		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 8 | \
 83		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 10 | \
 84		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 12 | \
 85		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 14)
 86
 87#define TX_MCS_MAP (IEEE80211_VHT_MCS_SUPPORT_0_9 << 0 | \
 88		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 2 | \
 89		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 4 | \
 90		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 6 | \
 91		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 8 | \
 92		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 10 | \
 93		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 12 | \
 94		    IEEE80211_VHT_MCS_SUPPORT_0_9 << 14)
 95
 96static struct ieee80211_supported_band band_5ghz = {
 97	.channels = &channel_5ghz,
 98	.bitrates = bitrates_5ghz,
 99	.band = NL80211_BAND_5GHZ,
100	.n_channels = 1,
101	.n_bitrates = ARRAY_SIZE(bitrates_5ghz),
102	.ht_cap = {
103		.ht_supported = true,
104		.cap = IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
105		       IEEE80211_HT_CAP_GRN_FLD |
106		       IEEE80211_HT_CAP_SGI_20 |
107		       IEEE80211_HT_CAP_SGI_40 |
108		       IEEE80211_HT_CAP_DSSSCCK40,
109		.ampdu_factor = 0x3,
110		.ampdu_density = 0x6,
111		.mcs = {
112			.rx_mask = {0xff, 0xff},
113			.tx_params = IEEE80211_HT_MCS_TX_DEFINED,
114		},
115	},
116	.vht_cap = {
117		.vht_supported = true,
118		.cap = IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
119		       IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ |
120		       IEEE80211_VHT_CAP_RXLDPC |
121		       IEEE80211_VHT_CAP_SHORT_GI_80 |
122		       IEEE80211_VHT_CAP_SHORT_GI_160 |
123		       IEEE80211_VHT_CAP_TXSTBC |
124		       IEEE80211_VHT_CAP_RXSTBC_1 |
125		       IEEE80211_VHT_CAP_RXSTBC_2 |
126		       IEEE80211_VHT_CAP_RXSTBC_3 |
127		       IEEE80211_VHT_CAP_RXSTBC_4 |
128		       IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK,
129		.vht_mcs = {
130			.rx_mcs_map = cpu_to_le16(RX_MCS_MAP),
131			.tx_mcs_map = cpu_to_le16(TX_MCS_MAP),
132		}
133	},
134};
135
136/* Assigned at module init. Guaranteed locally-administered and unicast. */
137static u8 fake_router_bssid[ETH_ALEN] __ro_after_init = {};
138
139static void virt_wifi_inform_bss(struct wiphy *wiphy)
140{
141	u64 tsf = div_u64(ktime_get_boottime_ns(), 1000);
142	struct cfg80211_bss *informed_bss;
143	static const struct {
144		u8 tag;
145		u8 len;
146		u8 ssid[8];
147	} __packed ssid = {
148		.tag = WLAN_EID_SSID,
149		.len = 8,
150		.ssid = "VirtWifi",
151	};
152
153	informed_bss = cfg80211_inform_bss(wiphy, &channel_5ghz,
154					   CFG80211_BSS_FTYPE_PRESP,
155					   fake_router_bssid, tsf,
156					   WLAN_CAPABILITY_ESS, 0,
157					   (void *)&ssid, sizeof(ssid),
158					   DBM_TO_MBM(-50), GFP_KERNEL);
159	cfg80211_put_bss(wiphy, informed_bss);
160}
161
162/* Called with the rtnl lock held. */
163static int virt_wifi_scan(struct wiphy *wiphy,
164			  struct cfg80211_scan_request *request)
165{
166	struct virt_wifi_wiphy_priv *priv = wiphy_priv(wiphy);
167
168	wiphy_debug(wiphy, "scan\n");
169
170	if (priv->scan_request || priv->being_deleted)
171		return -EBUSY;
172
173	priv->scan_request = request;
174	schedule_delayed_work(&priv->scan_result, HZ * 2);
175
176	return 0;
177}
178
179/* Acquires and releases the rdev BSS lock. */
180static void virt_wifi_scan_result(struct work_struct *work)
181{
182	struct virt_wifi_wiphy_priv *priv =
183		container_of(work, struct virt_wifi_wiphy_priv,
184			     scan_result.work);
185	struct wiphy *wiphy = priv_to_wiphy(priv);
186	struct cfg80211_scan_info scan_info = { .aborted = false };
187
188	virt_wifi_inform_bss(wiphy);
189
190	/* Schedules work which acquires and releases the rtnl lock. */
191	cfg80211_scan_done(priv->scan_request, &scan_info);
192	priv->scan_request = NULL;
193}
194
195/* May acquire and release the rdev BSS lock. */
196static void virt_wifi_cancel_scan(struct wiphy *wiphy)
197{
198	struct virt_wifi_wiphy_priv *priv = wiphy_priv(wiphy);
199
200	cancel_delayed_work_sync(&priv->scan_result);
201	/* Clean up dangling callbacks if necessary. */
202	if (priv->scan_request) {
203		struct cfg80211_scan_info scan_info = { .aborted = true };
204		/* Schedules work which acquires and releases the rtnl lock. */
205		cfg80211_scan_done(priv->scan_request, &scan_info);
206		priv->scan_request = NULL;
207	}
208}
209
210struct virt_wifi_netdev_priv {
211	struct delayed_work connect;
212	struct net_device *lowerdev;
213	struct net_device *upperdev;
214	u32 tx_packets;
215	u32 tx_failed;
216	u8 connect_requested_bss[ETH_ALEN];
217	bool is_up;
218	bool is_connected;
219	bool being_deleted;
220};
221
222/* Called with the rtnl lock held. */
223static int virt_wifi_connect(struct wiphy *wiphy, struct net_device *netdev,
224			     struct cfg80211_connect_params *sme)
225{
226	struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
227	bool could_schedule;
228
229	if (priv->being_deleted || !priv->is_up)
230		return -EBUSY;
231
232	could_schedule = schedule_delayed_work(&priv->connect, HZ * 2);
233	if (!could_schedule)
234		return -EBUSY;
235
236	if (sme->bssid) {
237		ether_addr_copy(priv->connect_requested_bss, sme->bssid);
238	} else {
239		virt_wifi_inform_bss(wiphy);
240		eth_zero_addr(priv->connect_requested_bss);
241	}
242
243	wiphy_debug(wiphy, "connect\n");
244
245	return 0;
246}
247
248/* Acquires and releases the rdev event lock. */
249static void virt_wifi_connect_complete(struct work_struct *work)
250{
251	struct virt_wifi_netdev_priv *priv =
252		container_of(work, struct virt_wifi_netdev_priv, connect.work);
253	u8 *requested_bss = priv->connect_requested_bss;
254	bool right_addr = ether_addr_equal(requested_bss, fake_router_bssid);
255	u16 status = WLAN_STATUS_SUCCESS;
256
257	if (is_zero_ether_addr(requested_bss))
258		requested_bss = NULL;
259
260	if (!priv->is_up || (requested_bss && !right_addr))
261		status = WLAN_STATUS_UNSPECIFIED_FAILURE;
262	else
263		priv->is_connected = true;
264
265	/* Schedules an event that acquires the rtnl lock. */
266	cfg80211_connect_result(priv->upperdev, requested_bss, NULL, 0, NULL, 0,
267				status, GFP_KERNEL);
268	netif_carrier_on(priv->upperdev);
269}
270
271/* May acquire and release the rdev event lock. */
272static void virt_wifi_cancel_connect(struct net_device *netdev)
273{
274	struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
275
276	/* If there is work pending, clean up dangling callbacks. */
277	if (cancel_delayed_work_sync(&priv->connect)) {
278		/* Schedules an event that acquires the rtnl lock. */
279		cfg80211_connect_result(priv->upperdev,
280					priv->connect_requested_bss, NULL, 0,
281					NULL, 0,
282					WLAN_STATUS_UNSPECIFIED_FAILURE,
283					GFP_KERNEL);
284	}
285}
286
287/* Called with the rtnl lock held. Acquires the rdev event lock. */
288static int virt_wifi_disconnect(struct wiphy *wiphy, struct net_device *netdev,
289				u16 reason_code)
290{
291	struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
292
293	if (priv->being_deleted)
294		return -EBUSY;
295
296	wiphy_debug(wiphy, "disconnect\n");
297	virt_wifi_cancel_connect(netdev);
298
299	cfg80211_disconnected(netdev, reason_code, NULL, 0, true, GFP_KERNEL);
300	priv->is_connected = false;
301	netif_carrier_off(netdev);
302
303	return 0;
304}
305
306/* Called with the rtnl lock held. */
307static int virt_wifi_get_station(struct wiphy *wiphy, struct net_device *dev,
308				 const u8 *mac, struct station_info *sinfo)
309{
310	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
311
312	wiphy_debug(wiphy, "get_station\n");
313
314	if (!priv->is_connected || !ether_addr_equal(mac, fake_router_bssid))
315		return -ENOENT;
316
317	sinfo->filled = BIT_ULL(NL80211_STA_INFO_TX_PACKETS) |
318		BIT_ULL(NL80211_STA_INFO_TX_FAILED) |
319		BIT_ULL(NL80211_STA_INFO_SIGNAL) |
320		BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
321	sinfo->tx_packets = priv->tx_packets;
322	sinfo->tx_failed = priv->tx_failed;
323	/* For CFG80211_SIGNAL_TYPE_MBM, value is expressed in _dBm_ */
324	sinfo->signal = -50;
325	sinfo->txrate = (struct rate_info) {
326		.legacy = 10, /* units are 100kbit/s */
327	};
328	return 0;
329}
330
331/* Called with the rtnl lock held. */
332static int virt_wifi_dump_station(struct wiphy *wiphy, struct net_device *dev,
333				  int idx, u8 *mac, struct station_info *sinfo)
334{
335	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
336
337	wiphy_debug(wiphy, "dump_station\n");
338
339	if (idx != 0 || !priv->is_connected)
340		return -ENOENT;
341
342	ether_addr_copy(mac, fake_router_bssid);
343	return virt_wifi_get_station(wiphy, dev, fake_router_bssid, sinfo);
344}
345
346static const struct cfg80211_ops virt_wifi_cfg80211_ops = {
347	.scan = virt_wifi_scan,
348
349	.connect = virt_wifi_connect,
350	.disconnect = virt_wifi_disconnect,
351
352	.get_station = virt_wifi_get_station,
353	.dump_station = virt_wifi_dump_station,
354};
355
356/* Acquires and releases the rtnl lock. */
357static struct wiphy *virt_wifi_make_wiphy(void)
358{
359	struct wiphy *wiphy;
360	struct virt_wifi_wiphy_priv *priv;
361	int err;
362
363	wiphy = wiphy_new(&virt_wifi_cfg80211_ops, sizeof(*priv));
364
365	if (!wiphy)
366		return NULL;
367
368	wiphy->max_scan_ssids = 4;
369	wiphy->max_scan_ie_len = 1000;
370	wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
371
372	wiphy->bands[NL80211_BAND_2GHZ] = &band_2ghz;
373	wiphy->bands[NL80211_BAND_5GHZ] = &band_5ghz;
374	wiphy->bands[NL80211_BAND_60GHZ] = NULL;
375
376	wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
377
378	priv = wiphy_priv(wiphy);
379	priv->being_deleted = false;
380	priv->scan_request = NULL;
381	INIT_DELAYED_WORK(&priv->scan_result, virt_wifi_scan_result);
382
383	err = wiphy_register(wiphy);
384	if (err < 0) {
385		wiphy_free(wiphy);
386		return NULL;
387	}
388
389	return wiphy;
390}
391
392/* Acquires and releases the rtnl lock. */
393static void virt_wifi_destroy_wiphy(struct wiphy *wiphy)
394{
395	struct virt_wifi_wiphy_priv *priv;
396
397	WARN(!wiphy, "%s called with null wiphy", __func__);
398	if (!wiphy)
399		return;
400
401	priv = wiphy_priv(wiphy);
402	priv->being_deleted = true;
403	virt_wifi_cancel_scan(wiphy);
404
405	if (wiphy->registered)
406		wiphy_unregister(wiphy);
407	wiphy_free(wiphy);
408}
409
410/* Enters and exits a RCU-bh critical section. */
411static netdev_tx_t virt_wifi_start_xmit(struct sk_buff *skb,
412					struct net_device *dev)
413{
414	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
415
416	priv->tx_packets++;
417	if (!priv->is_connected) {
418		priv->tx_failed++;
419		return NET_XMIT_DROP;
420	}
421
422	skb->dev = priv->lowerdev;
423	return dev_queue_xmit(skb);
424}
425
426/* Called with rtnl lock held. */
427static int virt_wifi_net_device_open(struct net_device *dev)
428{
429	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
430
431	priv->is_up = true;
432	return 0;
433}
434
435/* Called with rtnl lock held. */
436static int virt_wifi_net_device_stop(struct net_device *dev)
437{
438	struct virt_wifi_netdev_priv *n_priv = netdev_priv(dev);
439
440	n_priv->is_up = false;
441
442	if (!dev->ieee80211_ptr)
443		return 0;
444
445	virt_wifi_cancel_scan(dev->ieee80211_ptr->wiphy);
446	virt_wifi_cancel_connect(dev);
447	netif_carrier_off(dev);
448
449	return 0;
450}
451
452static int virt_wifi_net_device_get_iflink(const struct net_device *dev)
453{
454	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
455
456	return priv->lowerdev->ifindex;
457}
458
459static const struct net_device_ops virt_wifi_ops = {
460	.ndo_start_xmit = virt_wifi_start_xmit,
461	.ndo_open	= virt_wifi_net_device_open,
462	.ndo_stop	= virt_wifi_net_device_stop,
463	.ndo_get_iflink = virt_wifi_net_device_get_iflink,
464};
465
466/* Invoked as part of rtnl lock release. */
467static void virt_wifi_net_device_destructor(struct net_device *dev)
468{
469	/* Delayed past dellink to allow nl80211 to react to the device being
470	 * deleted.
471	 */
472	kfree(dev->ieee80211_ptr);
473	dev->ieee80211_ptr = NULL;
474}
475
476/* No lock interaction. */
477static void virt_wifi_setup(struct net_device *dev)
478{
479	ether_setup(dev);
480	dev->netdev_ops = &virt_wifi_ops;
481	dev->needs_free_netdev  = true;
482}
483
484/* Called in a RCU read critical section from netif_receive_skb */
485static rx_handler_result_t virt_wifi_rx_handler(struct sk_buff **pskb)
486{
487	struct sk_buff *skb = *pskb;
488	struct virt_wifi_netdev_priv *priv =
489		rcu_dereference(skb->dev->rx_handler_data);
490
491	if (!priv->is_connected)
492		return RX_HANDLER_PASS;
493
494	/* GFP_ATOMIC because this is a packet interrupt handler. */
495	skb = skb_share_check(skb, GFP_ATOMIC);
496	if (!skb) {
497		dev_err(&priv->upperdev->dev, "can't skb_share_check\n");
498		return RX_HANDLER_CONSUMED;
499	}
500
501	*pskb = skb;
502	skb->dev = priv->upperdev;
503	skb->pkt_type = PACKET_HOST;
504	return RX_HANDLER_ANOTHER;
505}
506
507/* Called with rtnl lock held. */
508static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
509			     struct nlattr *tb[], struct nlattr *data[],
510			     struct netlink_ext_ack *extack)
511{
512	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
513	int err;
514
515	if (!tb[IFLA_LINK])
516		return -EINVAL;
517
518	netif_carrier_off(dev);
519
520	priv->upperdev = dev;
521	priv->lowerdev = __dev_get_by_index(src_net,
522					    nla_get_u32(tb[IFLA_LINK]));
523
524	if (!priv->lowerdev)
525		return -ENODEV;
526	if (!tb[IFLA_MTU])
527		dev->mtu = priv->lowerdev->mtu;
528	else if (dev->mtu > priv->lowerdev->mtu)
529		return -EINVAL;
530
531	err = netdev_rx_handler_register(priv->lowerdev, virt_wifi_rx_handler,
532					 priv);
533	if (err) {
534		dev_err(&priv->lowerdev->dev,
535			"can't netdev_rx_handler_register: %d\n", err);
536		return err;
537	}
538
539	eth_hw_addr_inherit(dev, priv->lowerdev);
540	netif_stacked_transfer_operstate(priv->lowerdev, dev);
541
542	SET_NETDEV_DEV(dev, &priv->lowerdev->dev);
543	dev->ieee80211_ptr = kzalloc(sizeof(*dev->ieee80211_ptr), GFP_KERNEL);
544
545	if (!dev->ieee80211_ptr) {
546		err = -ENOMEM;
547		goto remove_handler;
548	}
549
550	dev->ieee80211_ptr->iftype = NL80211_IFTYPE_STATION;
551	dev->ieee80211_ptr->wiphy = common_wiphy;
552
553	err = register_netdevice(dev);
554	if (err) {
555		dev_err(&priv->lowerdev->dev, "can't register_netdevice: %d\n",
556			err);
557		goto free_wireless_dev;
558	}
559
560	err = netdev_upper_dev_link(priv->lowerdev, dev, extack);
561	if (err) {
562		dev_err(&priv->lowerdev->dev, "can't netdev_upper_dev_link: %d\n",
563			err);
564		goto unregister_netdev;
565	}
566
567	dev->priv_destructor = virt_wifi_net_device_destructor;
568	priv->being_deleted = false;
569	priv->is_connected = false;
570	priv->is_up = false;
571	INIT_DELAYED_WORK(&priv->connect, virt_wifi_connect_complete);
572	__module_get(THIS_MODULE);
573
574	return 0;
575unregister_netdev:
576	unregister_netdevice(dev);
577free_wireless_dev:
578	kfree(dev->ieee80211_ptr);
579	dev->ieee80211_ptr = NULL;
580remove_handler:
581	netdev_rx_handler_unregister(priv->lowerdev);
582
583	return err;
584}
585
586/* Called with rtnl lock held. */
587static void virt_wifi_dellink(struct net_device *dev,
588			      struct list_head *head)
589{
590	struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
591
592	if (dev->ieee80211_ptr)
593		virt_wifi_cancel_scan(dev->ieee80211_ptr->wiphy);
594
595	priv->being_deleted = true;
596	virt_wifi_cancel_connect(dev);
597	netif_carrier_off(dev);
598
599	netdev_rx_handler_unregister(priv->lowerdev);
600	netdev_upper_dev_unlink(priv->lowerdev, dev);
601
602	unregister_netdevice_queue(dev, head);
603	module_put(THIS_MODULE);
604
605	/* Deleting the wiphy is handled in the module destructor. */
606}
607
608static struct rtnl_link_ops virt_wifi_link_ops = {
609	.kind		= "virt_wifi",
610	.setup		= virt_wifi_setup,
611	.newlink	= virt_wifi_newlink,
612	.dellink	= virt_wifi_dellink,
613	.priv_size	= sizeof(struct virt_wifi_netdev_priv),
614};
615
616static bool netif_is_virt_wifi_dev(const struct net_device *dev)
617{
618	return rcu_access_pointer(dev->rx_handler) == virt_wifi_rx_handler;
619}
620
621static int virt_wifi_event(struct notifier_block *this, unsigned long event,
622			   void *ptr)
623{
624	struct net_device *lower_dev = netdev_notifier_info_to_dev(ptr);
625	struct virt_wifi_netdev_priv *priv;
626	struct net_device *upper_dev;
627	LIST_HEAD(list_kill);
628
629	if (!netif_is_virt_wifi_dev(lower_dev))
630		return NOTIFY_DONE;
631
632	switch (event) {
633	case NETDEV_UNREGISTER:
634		priv = rtnl_dereference(lower_dev->rx_handler_data);
635		if (!priv)
636			return NOTIFY_DONE;
637
638		upper_dev = priv->upperdev;
639
640		upper_dev->rtnl_link_ops->dellink(upper_dev, &list_kill);
641		unregister_netdevice_many(&list_kill);
642		break;
643	}
644
645	return NOTIFY_DONE;
646}
647
648static struct notifier_block virt_wifi_notifier = {
649	.notifier_call = virt_wifi_event,
650};
651
652/* Acquires and releases the rtnl lock. */
653static int __init virt_wifi_init_module(void)
654{
655	int err;
656
657	/* Guaranteed to be locally-administered and not multicast. */
658	eth_random_addr(fake_router_bssid);
659
660	err = register_netdevice_notifier(&virt_wifi_notifier);
661	if (err)
662		return err;
663
664	err = -ENOMEM;
665	common_wiphy = virt_wifi_make_wiphy();
666	if (!common_wiphy)
667		goto notifier;
668
669	err = rtnl_link_register(&virt_wifi_link_ops);
670	if (err)
671		goto destroy_wiphy;
672
673	return 0;
674
675destroy_wiphy:
676	virt_wifi_destroy_wiphy(common_wiphy);
677notifier:
678	unregister_netdevice_notifier(&virt_wifi_notifier);
679	return err;
680}
681
682/* Acquires and releases the rtnl lock. */
683static void __exit virt_wifi_cleanup_module(void)
684{
685	/* Will delete any devices that depend on the wiphy. */
686	rtnl_link_unregister(&virt_wifi_link_ops);
687	virt_wifi_destroy_wiphy(common_wiphy);
688	unregister_netdevice_notifier(&virt_wifi_notifier);
689}
690
691module_init(virt_wifi_init_module);
692module_exit(virt_wifi_cleanup_module);
693
694MODULE_LICENSE("GPL v2");
695MODULE_AUTHOR("Cody Schuffelen <schuffelen@google.com>");
696MODULE_DESCRIPTION("Driver for a wireless wrapper of ethernet devices");
697MODULE_ALIAS_RTNL_LINK("virt_wifi");