blob: 9f91fd8e6efb4bc3963c00325235126b0ed3f39c [file] [log] [blame]
Johannes Bergfe7a5d52009-11-18 18:42:47 +01001/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2008-2009 Johannes Berg <johannes@sipsolutions.net>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <net/mac80211.h>
13#include "ieee80211_i.h"
14#include "rate.h"
15#include "mesh.h"
16#include "led.h"
17
18
19void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
20 struct sk_buff *skb)
21{
22 struct ieee80211_local *local = hw_to_local(hw);
23 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
24 int tmp;
25
26 skb->pkt_type = IEEE80211_TX_STATUS_MSG;
27 skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
28 &local->skb_queue : &local->skb_queue_unreliable, skb);
29 tmp = skb_queue_len(&local->skb_queue) +
30 skb_queue_len(&local->skb_queue_unreliable);
31 while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
32 (skb = skb_dequeue(&local->skb_queue_unreliable))) {
33 dev_kfree_skb_irq(skb);
34 tmp--;
35 I802_DEBUG_INC(local->tx_status_drop);
36 }
37 tasklet_schedule(&local->tasklet);
38}
39EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
40
41static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
42 struct sta_info *sta,
43 struct sk_buff *skb)
44{
45 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
46
47 /*
48 * XXX: This is temporary!
49 *
50 * The problem here is that when we get here, the driver will
51 * quite likely have pretty much overwritten info->control by
52 * using info->driver_data or info->rate_driver_data. Thus,
53 * when passing out the frame to the driver again, we would be
54 * passing completely bogus data since the driver would then
55 * expect a properly filled info->control. In mac80211 itself
56 * the same problem occurs, since we need info->control.vif
57 * internally.
58 *
59 * To fix this, we should send the frame through TX processing
60 * again. However, it's not that simple, since the frame will
61 * have been software-encrypted (if applicable) already, and
62 * encrypting it again doesn't do much good. So to properly do
63 * that, we not only have to skip the actual 'raw' encryption
64 * (key selection etc. still has to be done!) but also the
65 * sequence number assignment since that impacts the crypto
66 * encapsulation, of course.
67 *
68 * Hence, for now, fix the bug by just dropping the frame.
69 */
70 goto drop;
71
72 sta->tx_filtered_count++;
73
74 /*
75 * Clear the TX filter mask for this STA when sending the next
76 * packet. If the STA went to power save mode, this will happen
77 * when it wakes up for the next time.
78 */
79 set_sta_flags(sta, WLAN_STA_CLEAR_PS_FILT);
80
81 /*
82 * This code races in the following way:
83 *
84 * (1) STA sends frame indicating it will go to sleep and does so
85 * (2) hardware/firmware adds STA to filter list, passes frame up
86 * (3) hardware/firmware processes TX fifo and suppresses a frame
87 * (4) we get TX status before having processed the frame and
88 * knowing that the STA has gone to sleep.
89 *
90 * This is actually quite unlikely even when both those events are
91 * processed from interrupts coming in quickly after one another or
92 * even at the same time because we queue both TX status events and
93 * RX frames to be processed by a tasklet and process them in the
94 * same order that they were received or TX status last. Hence, there
95 * is no race as long as the frame RX is processed before the next TX
96 * status, which drivers can ensure, see below.
97 *
98 * Note that this can only happen if the hardware or firmware can
99 * actually add STAs to the filter list, if this is done by the
100 * driver in response to set_tim() (which will only reduce the race
101 * this whole filtering tries to solve, not completely solve it)
102 * this situation cannot happen.
103 *
104 * To completely solve this race drivers need to make sure that they
105 * (a) don't mix the irq-safe/not irq-safe TX status/RX processing
106 * functions and
107 * (b) always process RX events before TX status events if ordering
108 * can be unknown, for example with different interrupt status
109 * bits.
110 */
111 if (test_sta_flags(sta, WLAN_STA_PS_STA) &&
112 skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) {
113 skb_queue_tail(&sta->tx_filtered, skb);
114 return;
115 }
116
117 if (!test_sta_flags(sta, WLAN_STA_PS_STA) &&
118 !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
119 /* Software retry the packet once */
120 info->flags |= IEEE80211_TX_INTFL_RETRIED;
121 ieee80211_add_pending_skb(local, skb);
122 return;
123 }
124
125 drop:
126#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
127 if (net_ratelimit())
128 printk(KERN_DEBUG "%s: dropped TX filtered frame, "
129 "queue_len=%d PS=%d @%lu\n",
130 wiphy_name(local->hw.wiphy),
131 skb_queue_len(&sta->tx_filtered),
132 !!test_sta_flags(sta, WLAN_STA_PS_STA), jiffies);
133#endif
134 dev_kfree_skb(skb);
135}
136
137void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
138{
139 struct sk_buff *skb2;
140 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
141 struct ieee80211_local *local = hw_to_local(hw);
142 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
143 u16 frag, type;
144 __le16 fc;
145 struct ieee80211_supported_band *sband;
146 struct ieee80211_tx_status_rtap_hdr *rthdr;
147 struct ieee80211_sub_if_data *sdata;
148 struct net_device *prev_dev = NULL;
149 struct sta_info *sta;
150 int retry_count = -1, i;
151
152 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
153 /* the HW cannot have attempted that rate */
154 if (i >= hw->max_rates) {
155 info->status.rates[i].idx = -1;
156 info->status.rates[i].count = 0;
157 }
158
159 retry_count += info->status.rates[i].count;
160 }
161 if (retry_count < 0)
162 retry_count = 0;
163
164 rcu_read_lock();
165
166 sband = local->hw.wiphy->bands[info->band];
167
168 sta = sta_info_get(local, hdr->addr1);
169
170 if (sta) {
171 if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
172 test_sta_flags(sta, WLAN_STA_PS_STA)) {
173 /*
174 * The STA is in power save mode, so assume
175 * that this TX packet failed because of that.
176 */
177 ieee80211_handle_filtered_frame(local, sta, skb);
178 rcu_read_unlock();
179 return;
180 }
181
182 fc = hdr->frame_control;
183
184 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
185 (ieee80211_is_data_qos(fc))) {
186 u16 tid, ssn;
187 u8 *qc;
188
189 qc = ieee80211_get_qos_ctl(hdr);
190 tid = qc[0] & 0xf;
191 ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
192 & IEEE80211_SCTL_SEQ);
193 ieee80211_send_bar(sta->sdata, hdr->addr1,
194 tid, ssn);
195 }
196
197 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
198 ieee80211_handle_filtered_frame(local, sta, skb);
199 rcu_read_unlock();
200 return;
201 } else {
202 if (!(info->flags & IEEE80211_TX_STAT_ACK))
203 sta->tx_retry_failed++;
204 sta->tx_retry_count += retry_count;
205 }
206
207 rate_control_tx_status(local, sband, sta, skb);
208 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
209 ieee80211s_update_metric(local, sta, skb);
210 }
211
212 rcu_read_unlock();
213
214 ieee80211_led_tx(local, 0);
215
216 /* SNMP counters
217 * Fragments are passed to low-level drivers as separate skbs, so these
218 * are actually fragments, not frames. Update frame counters only for
219 * the first fragment of the frame. */
220
221 frag = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
222 type = le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_FTYPE;
223
224 if (info->flags & IEEE80211_TX_STAT_ACK) {
225 if (frag == 0) {
226 local->dot11TransmittedFrameCount++;
227 if (is_multicast_ether_addr(hdr->addr1))
228 local->dot11MulticastTransmittedFrameCount++;
229 if (retry_count > 0)
230 local->dot11RetryCount++;
231 if (retry_count > 1)
232 local->dot11MultipleRetryCount++;
233 }
234
235 /* This counter shall be incremented for an acknowledged MPDU
236 * with an individual address in the address 1 field or an MPDU
237 * with a multicast address in the address 1 field of type Data
238 * or Management. */
239 if (!is_multicast_ether_addr(hdr->addr1) ||
240 type == IEEE80211_FTYPE_DATA ||
241 type == IEEE80211_FTYPE_MGMT)
242 local->dot11TransmittedFragmentCount++;
243 } else {
244 if (frag == 0)
245 local->dot11FailedCount++;
246 }
247
248 /* this was a transmitted frame, but now we want to reuse it */
249 skb_orphan(skb);
250
251 /*
252 * This is a bit racy but we can avoid a lot of work
253 * with this test...
254 */
255 if (!local->monitors && !local->cooked_mntrs) {
256 dev_kfree_skb(skb);
257 return;
258 }
259
260 /* send frame to monitor interfaces now */
261
262 if (skb_headroom(skb) < sizeof(*rthdr)) {
263 printk(KERN_ERR "ieee80211_tx_status: headroom too small\n");
264 dev_kfree_skb(skb);
265 return;
266 }
267
268 rthdr = (struct ieee80211_tx_status_rtap_hdr *)
269 skb_push(skb, sizeof(*rthdr));
270
271 memset(rthdr, 0, sizeof(*rthdr));
272 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
273 rthdr->hdr.it_present =
274 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
275 (1 << IEEE80211_RADIOTAP_DATA_RETRIES) |
276 (1 << IEEE80211_RADIOTAP_RATE));
277
278 if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
279 !is_multicast_ether_addr(hdr->addr1))
280 rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_FAIL);
281
282 /*
283 * XXX: Once radiotap gets the bitmap reset thing the vendor
284 * extensions proposal contains, we can actually report
285 * the whole set of tries we did.
286 */
287 if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
288 (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
289 rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_CTS);
290 else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
291 rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_RTS);
292 if (info->status.rates[0].idx >= 0 &&
293 !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))
294 rthdr->rate = sband->bitrates[
295 info->status.rates[0].idx].bitrate / 5;
296
297 /* for now report the total retry_count */
298 rthdr->data_retries = retry_count;
299
300 /* XXX: is this sufficient for BPF? */
301 skb_set_mac_header(skb, 0);
302 skb->ip_summed = CHECKSUM_UNNECESSARY;
303 skb->pkt_type = PACKET_OTHERHOST;
304 skb->protocol = htons(ETH_P_802_2);
305 memset(skb->cb, 0, sizeof(skb->cb));
306
307 rcu_read_lock();
308 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
309 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
310 if (!netif_running(sdata->dev))
311 continue;
312
313 if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
314 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
315 (type == IEEE80211_FTYPE_DATA))
316 continue;
317
318 if (prev_dev) {
319 skb2 = skb_clone(skb, GFP_ATOMIC);
320 if (skb2) {
321 skb2->dev = prev_dev;
322 netif_rx(skb2);
323 }
324 }
325
326 prev_dev = sdata->dev;
327 }
328 }
329 if (prev_dev) {
330 skb->dev = prev_dev;
331 netif_rx(skb);
332 skb = NULL;
333 }
334 rcu_read_unlock();
335 dev_kfree_skb(skb);
336}
337EXPORT_SYMBOL(ieee80211_tx_status);