]> err.no Git - linux-2.6/blob - drivers/net/wireless/rt2x00/rt2x00mac.c
rt2x00: Remove CTS/RTS check in tx()
[linux-2.6] / drivers / net / wireless / rt2x00 / rt2x00mac.c
1 /*
2         Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3         <http://rt2x00.serialmonkey.com>
4
5         This program is free software; you can redistribute it and/or modify
6         it under the terms of the GNU General Public License as published by
7         the Free Software Foundation; either version 2 of the License, or
8         (at your option) any later version.
9
10         This program is distributed in the hope that it will be useful,
11         but WITHOUT ANY WARRANTY; without even the implied warranty of
12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13         GNU General Public License for more details.
14
15         You should have received a copy of the GNU General Public License
16         along with this program; if not, write to the
17         Free Software Foundation, Inc.,
18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 /*
22         Module: rt2x00mac
23         Abstract: rt2x00 generic mac80211 routines.
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28
29 #include "rt2x00.h"
30 #include "rt2x00lib.h"
31
32 static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
33                                 struct data_queue *queue,
34                                 struct sk_buff *frag_skb)
35 {
36         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(frag_skb);
37         struct skb_frame_desc *skbdesc;
38         struct ieee80211_tx_info *rts_info;
39         struct sk_buff *skb;
40         int size;
41
42         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
43                 size = sizeof(struct ieee80211_cts);
44         else
45                 size = sizeof(struct ieee80211_rts);
46
47         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
48         if (!skb) {
49                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
50                 return NETDEV_TX_BUSY;
51         }
52
53         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
54         skb_put(skb, size);
55
56         /*
57          * Copy TX information over from original frame to
58          * RTS/CTS frame. Note that we set the no encryption flag
59          * since we don't want this frame to be encrypted.
60          * RTS frames should be acked, while CTS-to-self frames
61          * should not. The ready for TX flag is cleared to prevent
62          * it being automatically send when the descriptor is
63          * written to the hardware.
64          */
65         memcpy(skb->cb, frag_skb->cb, sizeof(skb->cb));
66         rts_info = IEEE80211_SKB_CB(skb);
67         rts_info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT;
68         rts_info->flags &= ~IEEE80211_TX_CTL_USE_CTS_PROTECT;
69         rts_info->flags &= ~IEEE80211_TX_CTL_REQ_TX_STATUS;
70
71         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
72                 rts_info->flags |= IEEE80211_TX_CTL_NO_ACK;
73         else
74                 rts_info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
75
76         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
77                 ieee80211_ctstoself_get(rt2x00dev->hw, tx_info->control.vif,
78                                         frag_skb->data, size, tx_info,
79                                         (struct ieee80211_cts *)(skb->data));
80         else
81                 ieee80211_rts_get(rt2x00dev->hw, tx_info->control.vif,
82                                   frag_skb->data, size, tx_info,
83                                   (struct ieee80211_rts *)(skb->data));
84
85         /*
86          * Initialize skb descriptor
87          */
88         skbdesc = get_skb_frame_desc(skb);
89         memset(skbdesc, 0, sizeof(*skbdesc));
90         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
91
92         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
93                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
94                 return NETDEV_TX_BUSY;
95         }
96
97         return NETDEV_TX_OK;
98 }
99
100 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
101 {
102         struct rt2x00_dev *rt2x00dev = hw->priv;
103         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
104         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
105         enum data_queue_qid qid = skb_get_queue_mapping(skb);
106         struct data_queue *queue;
107         u16 frame_control;
108
109         /*
110          * Mac80211 might be calling this function while we are trying
111          * to remove the device or perhaps suspending it.
112          * Note that we can only stop the TX queues inside the TX path
113          * due to possible race conditions in mac80211.
114          */
115         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
116                 ieee80211_stop_queues(hw);
117                 dev_kfree_skb_any(skb);
118                 return NETDEV_TX_OK;
119         }
120
121         /*
122          * Determine which queue to put packet on.
123          */
124         if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
125             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
126                 queue = rt2x00queue_get_queue(rt2x00dev, QID_ATIM);
127         else
128                 queue = rt2x00queue_get_queue(rt2x00dev, qid);
129         if (unlikely(!queue)) {
130                 ERROR(rt2x00dev,
131                       "Attempt to send packet over invalid queue %d.\n"
132                       "Please file bug report to %s.\n", qid, DRV_PROJECT);
133                 dev_kfree_skb_any(skb);
134                 return NETDEV_TX_OK;
135         }
136
137         /*
138          * If CTS/RTS is required. create and queue that frame first.
139          * Make sure we have at least enough entries available to send
140          * this CTS/RTS frame as well as the data frame.
141          * Note that when the driver has set the set_rts_threshold()
142          * callback function it doesn't need software generation of
143          * either RTS or CTS-to-self frame and handles everything
144          * inside the hardware.
145          */
146         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
147         if ((tx_info->flags & (IEEE80211_TX_CTL_USE_RTS_CTS |
148                                IEEE80211_TX_CTL_USE_CTS_PROTECT)) &&
149             !rt2x00dev->ops->hw->set_rts_threshold) {
150                 if (rt2x00queue_available(queue) <= 1) {
151                         ieee80211_stop_queue(rt2x00dev->hw, qid);
152                         return NETDEV_TX_BUSY;
153                 }
154
155                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb)) {
156                         ieee80211_stop_queue(rt2x00dev->hw, qid);
157                         return NETDEV_TX_BUSY;
158                 }
159         }
160
161         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
162                 ieee80211_stop_queue(rt2x00dev->hw, qid);
163                 return NETDEV_TX_BUSY;
164         }
165
166         if (rt2x00queue_full(queue))
167                 ieee80211_stop_queue(rt2x00dev->hw, qid);
168
169         if (rt2x00dev->ops->lib->kick_tx_queue)
170                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, qid);
171
172         return NETDEV_TX_OK;
173 }
174 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
175
176 int rt2x00mac_start(struct ieee80211_hw *hw)
177 {
178         struct rt2x00_dev *rt2x00dev = hw->priv;
179
180         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
181                 return 0;
182
183         return rt2x00lib_start(rt2x00dev);
184 }
185 EXPORT_SYMBOL_GPL(rt2x00mac_start);
186
187 void rt2x00mac_stop(struct ieee80211_hw *hw)
188 {
189         struct rt2x00_dev *rt2x00dev = hw->priv;
190
191         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
192                 return;
193
194         rt2x00lib_stop(rt2x00dev);
195 }
196 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
197
198 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
199                             struct ieee80211_if_init_conf *conf)
200 {
201         struct rt2x00_dev *rt2x00dev = hw->priv;
202         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
203         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, QID_BEACON);
204         struct queue_entry *entry = NULL;
205         unsigned int i;
206
207         /*
208          * Don't allow interfaces to be added
209          * the device has disappeared.
210          */
211         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
212             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
213                 return -ENODEV;
214
215         /*
216          * We don't support mixed combinations of sta and ap virtual
217          * interfaces. We can only add this interface when the rival
218          * interface count is 0.
219          */
220         if ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
221             (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count))
222                 return -ENOBUFS;
223
224         /*
225          * Check if we exceeded the maximum amount of supported interfaces.
226          */
227         if ((conf->type == IEEE80211_IF_TYPE_AP &&
228              rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
229             (conf->type != IEEE80211_IF_TYPE_AP &&
230              rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
231                 return -ENOBUFS;
232
233         /*
234          * Loop through all beacon queues to find a free
235          * entry. Since there are as much beacon entries
236          * as the maximum interfaces, this search shouldn't
237          * fail.
238          */
239         for (i = 0; i < queue->limit; i++) {
240                 entry = &queue->entries[i];
241                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
242                         break;
243         }
244
245         if (unlikely(i == queue->limit))
246                 return -ENOBUFS;
247
248         /*
249          * We are now absolutely sure the interface can be created,
250          * increase interface count and start initialization.
251          */
252
253         if (conf->type == IEEE80211_IF_TYPE_AP)
254                 rt2x00dev->intf_ap_count++;
255         else
256                 rt2x00dev->intf_sta_count++;
257
258         spin_lock_init(&intf->lock);
259         intf->beacon = entry;
260
261         if (conf->type == IEEE80211_IF_TYPE_AP)
262                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
263         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
264
265         /*
266          * The MAC adddress must be configured after the device
267          * has been initialized. Otherwise the device can reset
268          * the MAC registers.
269          */
270         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
271
272         /*
273          * Some filters depend on the current working mode. We can force
274          * an update during the next configure_filter() run by mac80211 by
275          * resetting the current packet_filter state.
276          */
277         rt2x00dev->packet_filter = 0;
278
279         return 0;
280 }
281 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
282
283 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
284                                 struct ieee80211_if_init_conf *conf)
285 {
286         struct rt2x00_dev *rt2x00dev = hw->priv;
287         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
288
289         /*
290          * Don't allow interfaces to be remove while
291          * either the device has disappeared or when
292          * no interface is present.
293          */
294         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
295             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
296             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
297                 return;
298
299         if (conf->type == IEEE80211_IF_TYPE_AP)
300                 rt2x00dev->intf_ap_count--;
301         else
302                 rt2x00dev->intf_sta_count--;
303
304         /*
305          * Release beacon entry so it is available for
306          * new interfaces again.
307          */
308         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
309
310         /*
311          * Make sure the bssid and mac address registers
312          * are cleared to prevent false ACKing of frames.
313          */
314         rt2x00lib_config_intf(rt2x00dev, intf,
315                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
316 }
317 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
318
319 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
320 {
321         struct rt2x00_dev *rt2x00dev = hw->priv;
322
323         /*
324          * Mac80211 might be calling this function while we are trying
325          * to remove the device or perhaps suspending it.
326          */
327         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
328                 return 0;
329
330         /*
331          * Check if we need to disable the radio,
332          * if this is not the case, at least the RX must be disabled.
333          */
334         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
335                 if (!conf->radio_enabled)
336                         rt2x00lib_disable_radio(rt2x00dev);
337                 else
338                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
339         }
340
341         rt2x00lib_config(rt2x00dev, conf, 0);
342
343         /*
344          * Reenable RX only if the radio should be on.
345          */
346         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
347                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
348         else if (conf->radio_enabled)
349                 return rt2x00lib_enable_radio(rt2x00dev);
350
351         return 0;
352 }
353 EXPORT_SYMBOL_GPL(rt2x00mac_config);
354
355 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
356                                struct ieee80211_vif *vif,
357                                struct ieee80211_if_conf *conf)
358 {
359         struct rt2x00_dev *rt2x00dev = hw->priv;
360         struct rt2x00_intf *intf = vif_to_intf(vif);
361         int status;
362
363         /*
364          * Mac80211 might be calling this function while we are trying
365          * to remove the device or perhaps suspending it.
366          */
367         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
368                 return 0;
369
370         spin_lock(&intf->lock);
371
372         /*
373          * If the interface does not work in master mode,
374          * then the bssid value in the interface structure
375          * should now be set.
376          */
377         if (conf->type != IEEE80211_IF_TYPE_AP)
378                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
379
380         spin_unlock(&intf->lock);
381
382         /*
383          * Call rt2x00_config_intf() outside of the spinlock context since
384          * the call will sleep for USB drivers. By using the ieee80211_if_conf
385          * values as arguments we make keep access to rt2x00_intf thread safe
386          * even without the lock.
387          */
388         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, conf->bssid);
389
390         /*
391          * We only need to initialize the beacon when master mode is enabled.
392          */
393         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
394                 return 0;
395
396         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw, conf->beacon);
397         if (status)
398                 dev_kfree_skb(conf->beacon);
399
400         return status;
401 }
402 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
403
404 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
405                                 unsigned int changed_flags,
406                                 unsigned int *total_flags,
407                                 int mc_count, struct dev_addr_list *mc_list)
408 {
409         struct rt2x00_dev *rt2x00dev = hw->priv;
410
411         /*
412          * Mask off any flags we are going to ignore
413          * from the total_flags field.
414          */
415         *total_flags &=
416             FIF_ALLMULTI |
417             FIF_FCSFAIL |
418             FIF_PLCPFAIL |
419             FIF_CONTROL |
420             FIF_OTHER_BSS |
421             FIF_PROMISC_IN_BSS;
422
423         /*
424          * Apply some rules to the filters:
425          * - Some filters imply different filters to be set.
426          * - Some things we can't filter out at all.
427          * - Multicast filter seems to kill broadcast traffic so never use it.
428          */
429         *total_flags |= FIF_ALLMULTI;
430         if (*total_flags & FIF_OTHER_BSS ||
431             *total_flags & FIF_PROMISC_IN_BSS)
432                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
433
434         /*
435          * Check if there is any work left for us.
436          */
437         if (rt2x00dev->packet_filter == *total_flags)
438                 return;
439         rt2x00dev->packet_filter = *total_flags;
440
441         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
442                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
443         else
444                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->filter_work);
445 }
446 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
447
448 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
449                         struct ieee80211_low_level_stats *stats)
450 {
451         struct rt2x00_dev *rt2x00dev = hw->priv;
452
453         /*
454          * The dot11ACKFailureCount, dot11RTSFailureCount and
455          * dot11RTSSuccessCount are updated in interrupt time.
456          * dot11FCSErrorCount is updated in the link tuner.
457          */
458         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
459
460         return 0;
461 }
462 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
463
464 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
465                            struct ieee80211_tx_queue_stats *stats)
466 {
467         struct rt2x00_dev *rt2x00dev = hw->priv;
468         unsigned int i;
469
470         for (i = 0; i < rt2x00dev->ops->tx_queues; i++) {
471                 stats[i].len = rt2x00dev->tx[i].length;
472                 stats[i].limit = rt2x00dev->tx[i].limit;
473                 stats[i].count = rt2x00dev->tx[i].count;
474         }
475
476         return 0;
477 }
478 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
479
480 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
481                                 struct ieee80211_vif *vif,
482                                 struct ieee80211_bss_conf *bss_conf,
483                                 u32 changes)
484 {
485         struct rt2x00_dev *rt2x00dev = hw->priv;
486         struct rt2x00_intf *intf = vif_to_intf(vif);
487         unsigned int delayed = 0;
488
489         /*
490          * When the association status has changed we must reset the link
491          * tuner counter. This is because some drivers determine if they
492          * should perform link tuning based on the number of seconds
493          * while associated or not associated.
494          */
495         if (changes & BSS_CHANGED_ASSOC) {
496                 rt2x00dev->link.count = 0;
497
498                 if (bss_conf->assoc)
499                         rt2x00dev->intf_associated++;
500                 else
501                         rt2x00dev->intf_associated--;
502
503                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
504                         rt2x00leds_led_assoc(rt2x00dev,
505                                              !!rt2x00dev->intf_associated);
506                 else
507                         delayed |= DELAYED_LED_ASSOC;
508         }
509
510         /*
511          * When the erp information has changed, we should perform
512          * additional configuration steps. For all other changes we are done.
513          */
514         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
515                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
516                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
517                 else
518                         delayed |= DELAYED_CONFIG_ERP;
519         }
520
521         spin_lock(&intf->lock);
522         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
523         if (delayed) {
524                 intf->delayed_flags |= delayed;
525                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->intf_work);
526         }
527         spin_unlock(&intf->lock);
528 }
529 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
530
531 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, u16 queue_idx,
532                       const struct ieee80211_tx_queue_params *params)
533 {
534         struct rt2x00_dev *rt2x00dev = hw->priv;
535         struct data_queue *queue;
536
537         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
538         if (unlikely(!queue))
539                 return -EINVAL;
540
541         /*
542          * The passed variables are stored as real value ((2^n)-1).
543          * Ralink registers require to know the bit number 'n'.
544          */
545         if (params->cw_min > 0)
546                 queue->cw_min = fls(params->cw_min);
547         else
548                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
549
550         if (params->cw_max > 0)
551                 queue->cw_max = fls(params->cw_max);
552         else
553                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
554
555         if (params->aifs >= 0)
556                 queue->aifs = params->aifs;
557         else
558                 queue->aifs = 2;
559
560         INFO(rt2x00dev,
561              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
562              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
563
564         return 0;
565 }
566 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);