2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <net/mac80211.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/netdevice.h>
15 #include <linux/types.h>
16 #include <linux/slab.h>
17 #include <linux/skbuff.h>
18 #include <linux/etherdevice.h>
19 #include <linux/if_arp.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/bitmap.h>
22 #include <linux/pm_qos_params.h>
23 #include <linux/inetdevice.h>
24 #include <net/net_namespace.h>
25 #include <net/cfg80211.h>
27 #include "ieee80211_i.h"
28 #include "driver-ops.h"
37 bool ieee80211_disable_40mhz_24ghz;
38 module_param(ieee80211_disable_40mhz_24ghz, bool, 0644);
39 MODULE_PARM_DESC(ieee80211_disable_40mhz_24ghz,
40 "Disable 40MHz support in the 2.4GHz band");
42 void ieee80211_configure_filter(struct ieee80211_local *local)
45 unsigned int changed_flags;
46 unsigned int new_flags = 0;
48 if (atomic_read(&local->iff_promiscs))
49 new_flags |= FIF_PROMISC_IN_BSS;
51 if (atomic_read(&local->iff_allmultis))
52 new_flags |= FIF_ALLMULTI;
54 if (local->monitors || local->scanning)
55 new_flags |= FIF_BCN_PRBRESP_PROMISC;
57 if (local->fif_fcsfail)
58 new_flags |= FIF_FCSFAIL;
60 if (local->fif_plcpfail)
61 new_flags |= FIF_PLCPFAIL;
63 if (local->fif_control)
64 new_flags |= FIF_CONTROL;
66 if (local->fif_other_bss)
67 new_flags |= FIF_OTHER_BSS;
69 if (local->fif_pspoll)
70 new_flags |= FIF_PSPOLL;
72 spin_lock_bh(&local->filter_lock);
73 changed_flags = local->filter_flags ^ new_flags;
75 mc = drv_prepare_multicast(local, &local->mc_list);
76 spin_unlock_bh(&local->filter_lock);
81 drv_configure_filter(local, changed_flags, &new_flags, mc);
83 WARN_ON(new_flags & (1<<31));
85 local->filter_flags = new_flags & ~(1<<31);
88 static void ieee80211_reconfig_filter(struct work_struct *work)
90 struct ieee80211_local *local =
91 container_of(work, struct ieee80211_local, reconfig_filter);
93 ieee80211_configure_filter(local);
96 int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
98 struct ieee80211_channel *chan, *scan_chan;
101 enum nl80211_channel_type channel_type;
105 scan_chan = local->scan_channel;
109 channel_type = NL80211_CHAN_NO_HT;
110 local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL;
111 } else if (local->tmp_channel) {
112 chan = scan_chan = local->tmp_channel;
113 channel_type = local->tmp_channel_type;
114 local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL;
116 chan = local->oper_channel;
117 channel_type = local->_oper_channel_type;
118 local->hw.conf.flags &= ~IEEE80211_CONF_OFFCHANNEL;
121 if (chan != local->hw.conf.channel ||
122 channel_type != local->hw.conf.channel_type) {
123 local->hw.conf.channel = chan;
124 local->hw.conf.channel_type = channel_type;
125 changed |= IEEE80211_CONF_CHANGE_CHANNEL;
128 if (!conf_is_ht(&local->hw.conf)) {
130 * mac80211.h documents that this is only valid
131 * when the channel is set to an HT type, and
132 * that otherwise STATIC is used.
134 local->hw.conf.smps_mode = IEEE80211_SMPS_STATIC;
135 } else if (local->hw.conf.smps_mode != local->smps_mode) {
136 local->hw.conf.smps_mode = local->smps_mode;
137 changed |= IEEE80211_CONF_CHANGE_SMPS;
141 power = chan->max_power;
143 power = local->power_constr_level ?
144 (chan->max_power - local->power_constr_level) :
147 if (local->user_power_level >= 0)
148 power = min(power, local->user_power_level);
150 if (local->hw.conf.power_level != power) {
151 changed |= IEEE80211_CONF_CHANGE_POWER;
152 local->hw.conf.power_level = power;
155 if (changed && local->open_count) {
156 ret = drv_config(local, changed);
159 * HW reconfiguration should never fail, the driver has told
160 * us what it can support so it should live up to that promise.
163 * rfkill is not integrated with mac80211 and a
164 * configuration command can thus fail if hardware rfkill
167 * FIXME: integrate rfkill with mac80211 and then add this
177 void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
180 struct ieee80211_local *local = sdata->local;
181 static const u8 zero[ETH_ALEN] = { 0 };
186 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
188 * While not associated, claim a BSSID of all-zeroes
189 * so that drivers don't do any weird things with the
190 * BSSID at that time.
192 if (sdata->vif.bss_conf.assoc)
193 sdata->vif.bss_conf.bssid = sdata->u.mgd.bssid;
195 sdata->vif.bss_conf.bssid = zero;
196 } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
197 sdata->vif.bss_conf.bssid = sdata->u.ibss.bssid;
198 else if (sdata->vif.type == NL80211_IFTYPE_AP)
199 sdata->vif.bss_conf.bssid = sdata->vif.addr;
200 else if (ieee80211_vif_is_mesh(&sdata->vif)) {
201 sdata->vif.bss_conf.bssid = zero;
207 switch (sdata->vif.type) {
208 case NL80211_IFTYPE_AP:
209 case NL80211_IFTYPE_ADHOC:
210 case NL80211_IFTYPE_MESH_POINT:
213 /* do not warn to simplify caller in scan.c */
214 changed &= ~BSS_CHANGED_BEACON_ENABLED;
215 if (WARN_ON(changed & BSS_CHANGED_BEACON))
220 if (changed & BSS_CHANGED_BEACON_ENABLED) {
221 if (local->quiescing || !ieee80211_sdata_running(sdata) ||
222 test_bit(SCAN_SW_SCANNING, &local->scanning)) {
223 sdata->vif.bss_conf.enable_beacon = false;
226 * Beacon should be enabled, but AP mode must
227 * check whether there is a beacon configured.
229 switch (sdata->vif.type) {
230 case NL80211_IFTYPE_AP:
231 sdata->vif.bss_conf.enable_beacon =
232 !!sdata->u.ap.beacon;
234 case NL80211_IFTYPE_ADHOC:
235 sdata->vif.bss_conf.enable_beacon =
236 !!sdata->u.ibss.presp;
238 case NL80211_IFTYPE_MESH_POINT:
239 sdata->vif.bss_conf.enable_beacon = true;
249 drv_bss_info_changed(local, sdata, &sdata->vif.bss_conf, changed);
252 u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
254 sdata->vif.bss_conf.use_cts_prot = false;
255 sdata->vif.bss_conf.use_short_preamble = false;
256 sdata->vif.bss_conf.use_short_slot = false;
257 return BSS_CHANGED_ERP_CTS_PROT |
258 BSS_CHANGED_ERP_PREAMBLE |
259 BSS_CHANGED_ERP_SLOT;
262 static void ieee80211_tasklet_handler(unsigned long data)
264 struct ieee80211_local *local = (struct ieee80211_local *) data;
267 while ((skb = skb_dequeue(&local->skb_queue)) ||
268 (skb = skb_dequeue(&local->skb_queue_unreliable))) {
269 switch (skb->pkt_type) {
270 case IEEE80211_RX_MSG:
271 /* Clear skb->pkt_type in order to not confuse kernel
274 ieee80211_rx(local_to_hw(local), skb);
276 case IEEE80211_TX_STATUS_MSG:
278 ieee80211_tx_status(local_to_hw(local), skb);
281 WARN(1, "mac80211: Packet is of unknown type %d\n",
289 static void ieee80211_restart_work(struct work_struct *work)
291 struct ieee80211_local *local =
292 container_of(work, struct ieee80211_local, restart_work);
295 ieee80211_reconfig(local);
299 void ieee80211_restart_hw(struct ieee80211_hw *hw)
301 struct ieee80211_local *local = hw_to_local(hw);
303 trace_api_restart_hw(local);
305 /* use this reason, __ieee80211_resume will unblock it */
306 ieee80211_stop_queues_by_reason(hw,
307 IEEE80211_QUEUE_STOP_REASON_SUSPEND);
309 schedule_work(&local->restart_work);
311 EXPORT_SYMBOL(ieee80211_restart_hw);
313 static void ieee80211_recalc_smps_work(struct work_struct *work)
315 struct ieee80211_local *local =
316 container_of(work, struct ieee80211_local, recalc_smps);
318 mutex_lock(&local->iflist_mtx);
319 ieee80211_recalc_smps(local, NULL);
320 mutex_unlock(&local->iflist_mtx);
324 static int ieee80211_ifa_changed(struct notifier_block *nb,
325 unsigned long data, void *arg)
327 struct in_ifaddr *ifa = arg;
328 struct ieee80211_local *local =
329 container_of(nb, struct ieee80211_local,
331 struct net_device *ndev = ifa->ifa_dev->dev;
332 struct wireless_dev *wdev = ndev->ieee80211_ptr;
333 struct in_device *idev;
334 struct ieee80211_sub_if_data *sdata;
335 struct ieee80211_bss_conf *bss_conf;
336 struct ieee80211_if_managed *ifmgd;
339 if (!netif_running(ndev))
342 /* Make sure it's our interface that got changed */
346 if (wdev->wiphy != local->hw.wiphy)
349 sdata = IEEE80211_DEV_TO_SUB_IF(ndev);
350 bss_conf = &sdata->vif.bss_conf;
352 /* ARP filtering is only supported in managed mode */
353 if (sdata->vif.type != NL80211_IFTYPE_STATION)
356 idev = sdata->dev->ip_ptr;
360 ifmgd = &sdata->u.mgd;
361 mutex_lock(&ifmgd->mtx);
363 /* Copy the addresses to the bss_conf list */
364 ifa = idev->ifa_list;
365 while (c < IEEE80211_BSS_ARP_ADDR_LIST_LEN && ifa) {
366 bss_conf->arp_addr_list[c] = ifa->ifa_address;
371 /* If not all addresses fit the list, disable filtering */
373 sdata->arp_filter_state = false;
376 sdata->arp_filter_state = true;
378 bss_conf->arp_addr_cnt = c;
380 /* Configure driver only if associated */
381 if (ifmgd->associated) {
382 bss_conf->arp_filter_enabled = sdata->arp_filter_state;
383 ieee80211_bss_info_change_notify(sdata,
384 BSS_CHANGED_ARP_FILTER);
387 mutex_unlock(&ifmgd->mtx);
393 struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
394 const struct ieee80211_ops *ops)
396 struct ieee80211_local *local;
400 /* Ensure 32-byte alignment of our private data and hw private data.
401 * We use the wiphy priv data for both our ieee80211_local and for
402 * the driver's private data
404 * In memory it'll be like this:
406 * +-------------------------+
408 * +-------------------------+
409 * | struct ieee80211_local |
410 * +-------------------------+
411 * | driver's private data |
412 * +-------------------------+
415 priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
417 wiphy = wiphy_new(&mac80211_config_ops, priv_size);
422 wiphy->flags |= WIPHY_FLAG_NETNS_OK |
423 WIPHY_FLAG_4ADDR_AP |
424 WIPHY_FLAG_4ADDR_STATION;
425 wiphy->privid = mac80211_wiphy_privid;
427 wiphy->bss_priv_size = sizeof(struct ieee80211_bss);
429 local = wiphy_priv(wiphy);
431 local->hw.wiphy = wiphy;
433 local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
438 BUG_ON(!ops->config);
439 BUG_ON(!ops->add_interface);
440 BUG_ON(!ops->remove_interface);
441 BUG_ON(!ops->configure_filter);
444 /* set up some defaults */
445 local->hw.queues = 1;
446 local->hw.max_rates = 1;
447 local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
448 local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
449 local->user_power_level = -1;
450 local->uapsd_queues = IEEE80211_DEFAULT_UAPSD_QUEUES;
451 local->uapsd_max_sp_len = IEEE80211_DEFAULT_MAX_SP_LEN;
453 INIT_LIST_HEAD(&local->interfaces);
455 __hw_addr_init(&local->mc_list);
457 mutex_init(&local->iflist_mtx);
458 mutex_init(&local->scan_mtx);
460 mutex_init(&local->key_mtx);
461 spin_lock_init(&local->filter_lock);
462 spin_lock_init(&local->queue_stop_reason_lock);
464 INIT_DELAYED_WORK(&local->scan_work, ieee80211_scan_work);
466 ieee80211_work_init(local);
468 INIT_WORK(&local->restart_work, ieee80211_restart_work);
470 INIT_WORK(&local->reconfig_filter, ieee80211_reconfig_filter);
471 INIT_WORK(&local->recalc_smps, ieee80211_recalc_smps_work);
472 local->smps_mode = IEEE80211_SMPS_OFF;
474 INIT_WORK(&local->dynamic_ps_enable_work,
475 ieee80211_dynamic_ps_enable_work);
476 INIT_WORK(&local->dynamic_ps_disable_work,
477 ieee80211_dynamic_ps_disable_work);
478 setup_timer(&local->dynamic_ps_timer,
479 ieee80211_dynamic_ps_timer, (unsigned long) local);
481 sta_info_init(local);
483 for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
484 skb_queue_head_init(&local->pending[i]);
485 atomic_set(&local->agg_queue_stop[i], 0);
487 tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending,
488 (unsigned long)local);
490 tasklet_init(&local->tasklet,
491 ieee80211_tasklet_handler,
492 (unsigned long) local);
494 skb_queue_head_init(&local->skb_queue);
495 skb_queue_head_init(&local->skb_queue_unreliable);
497 return local_to_hw(local);
499 EXPORT_SYMBOL(ieee80211_alloc_hw);
501 int ieee80211_register_hw(struct ieee80211_hw *hw)
503 struct ieee80211_local *local = hw_to_local(hw);
505 enum ieee80211_band band;
506 int channels, max_bitrates;
508 static const u32 cipher_suites[] = {
509 WLAN_CIPHER_SUITE_WEP40,
510 WLAN_CIPHER_SUITE_WEP104,
511 WLAN_CIPHER_SUITE_TKIP,
512 WLAN_CIPHER_SUITE_CCMP,
514 /* keep last -- depends on hw flags! */
515 WLAN_CIPHER_SUITE_AES_CMAC
519 * generic code guarantees at least one band,
520 * set this very early because much code assumes
521 * that hw.conf.channel is assigned
526 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
527 struct ieee80211_supported_band *sband;
529 sband = local->hw.wiphy->bands[band];
532 if (!local->oper_channel) {
533 /* init channel we're on */
534 local->hw.conf.channel =
535 local->oper_channel = &sband->channels[0];
536 local->hw.conf.channel_type = NL80211_CHAN_NO_HT;
538 channels += sband->n_channels;
540 if (max_bitrates < sband->n_bitrates)
541 max_bitrates = sband->n_bitrates;
542 supp_ht = supp_ht || sband->ht_cap.ht_supported;
545 local->int_scan_req = kzalloc(sizeof(*local->int_scan_req) +
546 sizeof(void *) * channels, GFP_KERNEL);
547 if (!local->int_scan_req)
550 /* if low-level driver supports AP, we also support VLAN */
551 if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP))
552 local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
554 /* mac80211 always supports monitor */
555 local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
557 if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
558 local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
559 else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
560 local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_UNSPEC;
562 WARN((local->hw.flags & IEEE80211_HW_SUPPORTS_UAPSD)
563 && (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK),
564 "U-APSD not supported with HW_PS_NULLFUNC_STACK\n");
567 * Calculate scan IE length -- we need this to alloc
568 * memory and to subtract from the driver limit. It
569 * includes the (extended) supported rates and HT
570 * information -- SSID is the driver's responsibility.
572 local->scan_ies_len = 4 + max_bitrates; /* (ext) supp rates */
574 local->scan_ies_len += 2 + sizeof(struct ieee80211_ht_cap);
576 if (!local->ops->hw_scan) {
577 /* For hw_scan, driver needs to set these up. */
578 local->hw.wiphy->max_scan_ssids = 4;
579 local->hw.wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN;
583 * If the driver supports any scan IEs, then assume the
584 * limit includes the IEs mac80211 will add, otherwise
585 * leave it at zero and let the driver sort it out; we
586 * still pass our IEs to the driver but userspace will
587 * not be allowed to in that case.
589 if (local->hw.wiphy->max_scan_ie_len)
590 local->hw.wiphy->max_scan_ie_len -= local->scan_ies_len;
592 local->hw.wiphy->cipher_suites = cipher_suites;
593 local->hw.wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
594 if (!(local->hw.flags & IEEE80211_HW_MFP_CAPABLE))
595 local->hw.wiphy->n_cipher_suites--;
597 result = wiphy_register(local->hw.wiphy);
599 goto fail_wiphy_register;
602 * We use the number of queues for feature tests (QoS, HT) internally
603 * so restrict them appropriately.
605 if (hw->queues > IEEE80211_MAX_QUEUES)
606 hw->queues = IEEE80211_MAX_QUEUES;
609 create_singlethread_workqueue(wiphy_name(local->hw.wiphy));
610 if (!local->workqueue) {
616 * The hardware needs headroom for sending the frame,
617 * and we need some headroom for passing the frame to monitor
618 * interfaces, but never both at the same time.
620 BUILD_BUG_ON(IEEE80211_TX_STATUS_HEADROOM !=
621 sizeof(struct ieee80211_tx_status_rtap_hdr));
622 local->tx_headroom = max_t(unsigned int , local->hw.extra_tx_headroom,
623 sizeof(struct ieee80211_tx_status_rtap_hdr));
625 debugfs_hw_add(local);
628 * if the driver doesn't specify a max listen interval we
629 * use 5 which should be a safe default
631 if (local->hw.max_listen_interval == 0)
632 local->hw.max_listen_interval = 5;
634 local->hw.conf.listen_interval = local->hw.max_listen_interval;
636 local->dynamic_ps_forced_timeout = -1;
638 result = sta_info_start(local);
642 result = ieee80211_wep_init(local);
644 printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",
645 wiphy_name(local->hw.wiphy), result);
649 result = ieee80211_init_rate_ctrl_alg(local,
650 hw->rate_control_algorithm);
652 printk(KERN_DEBUG "%s: Failed to initialize rate control "
653 "algorithm\n", wiphy_name(local->hw.wiphy));
657 /* add one default STA interface if supported */
658 if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {
659 result = ieee80211_if_add(local, "wlan%d", NULL,
660 NL80211_IFTYPE_STATION, NULL);
662 printk(KERN_WARNING "%s: Failed to add default virtual iface\n",
663 wiphy_name(local->hw.wiphy));
668 ieee80211_led_init(local);
670 local->network_latency_notifier.notifier_call =
671 ieee80211_max_network_latency;
672 result = pm_qos_add_notifier(PM_QOS_NETWORK_LATENCY,
673 &local->network_latency_notifier);
680 local->ifa_notifier.notifier_call = ieee80211_ifa_changed;
681 result = register_inetaddr_notifier(&local->ifa_notifier);
690 pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
691 &local->network_latency_notifier);
695 ieee80211_led_exit(local);
696 ieee80211_remove_interfaces(local);
699 ieee80211_wep_free(local);
700 sta_info_stop(local);
702 destroy_workqueue(local->workqueue);
704 wiphy_unregister(local->hw.wiphy);
706 kfree(local->int_scan_req);
709 EXPORT_SYMBOL(ieee80211_register_hw);
711 void ieee80211_unregister_hw(struct ieee80211_hw *hw)
713 struct ieee80211_local *local = hw_to_local(hw);
715 tasklet_kill(&local->tx_pending_tasklet);
716 tasklet_kill(&local->tasklet);
718 pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
719 &local->network_latency_notifier);
721 unregister_inetaddr_notifier(&local->ifa_notifier);
727 * At this point, interface list manipulations are fine
728 * because the driver cannot be handing us frames any
729 * more and the tasklet is killed.
731 ieee80211_remove_interfaces(local);
736 * Now all work items will be gone, but the
737 * timer might still be armed, so delete it
739 del_timer_sync(&local->work_timer);
741 cancel_work_sync(&local->reconfig_filter);
743 ieee80211_clear_tx_pending(local);
744 sta_info_stop(local);
745 rate_control_deinitialize(local);
747 if (skb_queue_len(&local->skb_queue) ||
748 skb_queue_len(&local->skb_queue_unreliable))
749 printk(KERN_WARNING "%s: skb_queue not empty\n",
750 wiphy_name(local->hw.wiphy));
751 skb_queue_purge(&local->skb_queue);
752 skb_queue_purge(&local->skb_queue_unreliable);
754 destroy_workqueue(local->workqueue);
755 wiphy_unregister(local->hw.wiphy);
756 ieee80211_wep_free(local);
757 ieee80211_led_exit(local);
758 kfree(local->int_scan_req);
760 EXPORT_SYMBOL(ieee80211_unregister_hw);
762 void ieee80211_free_hw(struct ieee80211_hw *hw)
764 struct ieee80211_local *local = hw_to_local(hw);
766 mutex_destroy(&local->iflist_mtx);
767 mutex_destroy(&local->scan_mtx);
769 wiphy_free(local->hw.wiphy);
771 EXPORT_SYMBOL(ieee80211_free_hw);
773 static int __init ieee80211_init(void)
778 BUILD_BUG_ON(sizeof(struct ieee80211_tx_info) > sizeof(skb->cb));
779 BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, driver_data) +
780 IEEE80211_TX_INFO_DRIVER_DATA_SIZE > sizeof(skb->cb));
782 ret = rc80211_minstrel_init();
786 ret = rc80211_minstrel_ht_init();
790 ret = rc80211_pid_init();
794 ret = ieee80211_iface_init();
802 rc80211_minstrel_ht_exit();
804 rc80211_minstrel_exit();
809 static void __exit ieee80211_exit(void)
812 rc80211_minstrel_ht_exit();
813 rc80211_minstrel_exit();
816 * For key todo, it'll be empty by now but the work
817 * might still be scheduled.
819 flush_scheduled_work();
824 ieee80211_iface_exit();
828 subsys_initcall(ieee80211_init);
829 module_exit(ieee80211_exit);
831 MODULE_DESCRIPTION("IEEE 802.11 subsystem");
832 MODULE_LICENSE("GPL");