Commit | Line | Data |
---|---|---|
0a51b27e | 1 | /* |
5484e237 JB |
2 | * Scanning implementation |
3 | * | |
0a51b27e JB |
4 | * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> |
5 | * Copyright 2004, Instant802 Networks, Inc. | |
6 | * Copyright 2005, Devicescape Software, Inc. | |
7 | * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> | |
8 | * Copyright 2007, Michael Wu <flamingice@sourmilk.net> | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License version 2 as | |
12 | * published by the Free Software Foundation. | |
13 | */ | |
14 | ||
0a51b27e | 15 | #include <linux/if_arp.h> |
078e1e60 | 16 | #include <linux/rtnetlink.h> |
e8db0be1 | 17 | #include <linux/pm_qos.h> |
df13cce5 | 18 | #include <net/sch_generic.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
bc3b2d7f | 20 | #include <linux/export.h> |
0a51b27e | 21 | #include <net/mac80211.h> |
0a51b27e JB |
22 | |
23 | #include "ieee80211_i.h" | |
24487981 | 24 | #include "driver-ops.h" |
5484e237 | 25 | #include "mesh.h" |
0a51b27e JB |
26 | |
27 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
28 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 29 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 30 | |
c2b13452 | 31 | struct ieee80211_bss * |
5484e237 JB |
32 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
33 | u8 *ssid, u8 ssid_len) | |
34 | { | |
0c1ad2ca JB |
35 | struct cfg80211_bss *cbss; |
36 | ||
37 | cbss = cfg80211_get_bss(local->hw.wiphy, | |
38 | ieee80211_get_channel(local->hw.wiphy, freq), | |
39 | bssid, ssid, ssid_len, 0, 0); | |
40 | if (!cbss) | |
41 | return NULL; | |
42 | return (void *)cbss->priv; | |
5484e237 JB |
43 | } |
44 | ||
00d3f14c | 45 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 46 | { |
0c1ad2ca | 47 | struct ieee80211_bss *bss = (void *)cbss->priv; |
5484e237 | 48 | |
5484e237 JB |
49 | kfree(bss_mesh_id(bss)); |
50 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
51 | } |
52 | ||
53 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 54 | struct ieee80211_bss *bss) |
5484e237 | 55 | { |
0c1ad2ca JB |
56 | if (!bss) |
57 | return; | |
58 | cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); | |
5484e237 JB |
59 | } |
60 | ||
ab13315a KV |
61 | static bool is_uapsd_supported(struct ieee802_11_elems *elems) |
62 | { | |
63 | u8 qos_info; | |
64 | ||
65 | if (elems->wmm_info && elems->wmm_info_len == 7 | |
66 | && elems->wmm_info[5] == 1) | |
67 | qos_info = elems->wmm_info[6]; | |
68 | else if (elems->wmm_param && elems->wmm_param_len == 24 | |
69 | && elems->wmm_param[5] == 1) | |
70 | qos_info = elems->wmm_param[6]; | |
71 | else | |
72 | /* no valid wmm information or parameter element found */ | |
73 | return false; | |
74 | ||
75 | return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; | |
76 | } | |
77 | ||
c2b13452 | 78 | struct ieee80211_bss * |
5484e237 JB |
79 | ieee80211_bss_info_update(struct ieee80211_local *local, |
80 | struct ieee80211_rx_status *rx_status, | |
81 | struct ieee80211_mgmt *mgmt, | |
82 | size_t len, | |
83 | struct ieee802_11_elems *elems, | |
2a519311 JB |
84 | struct ieee80211_channel *channel, |
85 | bool beacon) | |
5484e237 | 86 | { |
0c1ad2ca | 87 | struct cfg80211_bss *cbss; |
c2b13452 | 88 | struct ieee80211_bss *bss; |
f0b058b6 | 89 | int clen, srlen; |
2a519311 JB |
90 | s32 signal = 0; |
91 | ||
77965c97 | 92 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 93 | signal = rx_status->signal * 100; |
77965c97 | 94 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 95 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 96 | |
0c1ad2ca JB |
97 | cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
98 | mgmt, len, signal, GFP_ATOMIC); | |
5484e237 | 99 | |
0c1ad2ca | 100 | if (!cbss) |
00d3f14c JB |
101 | return NULL; |
102 | ||
0c1ad2ca JB |
103 | cbss->free_priv = ieee80211_rx_bss_free; |
104 | bss = (void *)cbss->priv; | |
5484e237 JB |
105 | |
106 | /* save the ERP value so that it is available at association time */ | |
107 | if (elems->erp_info && elems->erp_info_len >= 1) { | |
108 | bss->erp_value = elems->erp_info[0]; | |
109 | bss->has_erp_value = 1; | |
110 | } | |
111 | ||
5484e237 JB |
112 | if (elems->tim) { |
113 | struct ieee80211_tim_ie *tim_ie = | |
114 | (struct ieee80211_tim_ie *)elems->tim; | |
115 | bss->dtim_period = tim_ie->dtim_period; | |
116 | } | |
117 | ||
e5b900d2 JB |
118 | /* If the beacon had no TIM IE, or it was invalid, use 1 */ |
119 | if (beacon && !bss->dtim_period) | |
120 | bss->dtim_period = 1; | |
121 | ||
f0b058b6 SG |
122 | /* replace old supported rates if we get new values */ |
123 | srlen = 0; | |
5484e237 | 124 | if (elems->supp_rates) { |
f0b058b6 | 125 | clen = IEEE80211_MAX_SUPP_RATES; |
5484e237 JB |
126 | if (clen > elems->supp_rates_len) |
127 | clen = elems->supp_rates_len; | |
f0b058b6 SG |
128 | memcpy(bss->supp_rates, elems->supp_rates, clen); |
129 | srlen += clen; | |
5484e237 JB |
130 | } |
131 | if (elems->ext_supp_rates) { | |
f0b058b6 | 132 | clen = IEEE80211_MAX_SUPP_RATES - srlen; |
5484e237 JB |
133 | if (clen > elems->ext_supp_rates_len) |
134 | clen = elems->ext_supp_rates_len; | |
f0b058b6 SG |
135 | memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen); |
136 | srlen += clen; | |
5484e237 | 137 | } |
f0b058b6 SG |
138 | if (srlen) |
139 | bss->supp_rates_len = srlen; | |
5484e237 | 140 | |
5484e237 | 141 | bss->wmm_used = elems->wmm_param || elems->wmm_info; |
ab13315a | 142 | bss->uapsd_supported = is_uapsd_supported(elems); |
5484e237 JB |
143 | |
144 | if (!beacon) | |
145 | bss->last_probe_resp = jiffies; | |
146 | ||
5484e237 JB |
147 | return bss; |
148 | } | |
0a51b27e | 149 | |
98c8fccf | 150 | ieee80211_rx_result |
f1d58c25 | 151 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 152 | { |
f1d58c25 | 153 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 154 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 155 | struct ieee80211_bss *bss; |
98c8fccf JB |
156 | u8 *elements; |
157 | struct ieee80211_channel *channel; | |
158 | size_t baselen; | |
159 | int freq; | |
160 | __le16 fc; | |
161 | bool presp, beacon = false; | |
162 | struct ieee802_11_elems elems; | |
163 | ||
164 | if (skb->len < 2) | |
165 | return RX_DROP_UNUSABLE; | |
166 | ||
167 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
168 | fc = mgmt->frame_control; | |
169 | ||
170 | if (ieee80211_is_ctl(fc)) | |
171 | return RX_CONTINUE; | |
172 | ||
173 | if (skb->len < 24) | |
306fe938 | 174 | return RX_CONTINUE; |
98c8fccf JB |
175 | |
176 | presp = ieee80211_is_probe_resp(fc); | |
177 | if (presp) { | |
178 | /* ignore ProbeResp to foreign address */ | |
47846c9b | 179 | if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) |
98c8fccf JB |
180 | return RX_DROP_MONITOR; |
181 | ||
182 | presp = true; | |
183 | elements = mgmt->u.probe_resp.variable; | |
184 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
185 | } else { | |
186 | beacon = ieee80211_is_beacon(fc); | |
187 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
188 | elements = mgmt->u.beacon.variable; | |
189 | } | |
190 | ||
191 | if (!presp && !beacon) | |
192 | return RX_CONTINUE; | |
193 | ||
194 | if (baselen > skb->len) | |
195 | return RX_DROP_MONITOR; | |
196 | ||
197 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
198 | ||
199 | if (elems.ds_params && elems.ds_params_len == 1) | |
59eb21a6 BR |
200 | freq = ieee80211_channel_to_frequency(elems.ds_params[0], |
201 | rx_status->band); | |
98c8fccf JB |
202 | else |
203 | freq = rx_status->freq; | |
204 | ||
205 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
206 | ||
207 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
208 | return RX_DROP_MONITOR; | |
209 | ||
210 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
211 | mgmt, skb->len, &elems, | |
2a519311 | 212 | channel, beacon); |
d048e503 JM |
213 | if (bss) |
214 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf | 215 | |
07ef03ee | 216 | if (channel == sdata->local->oper_channel) |
b23b025f BG |
217 | return RX_CONTINUE; |
218 | ||
98c8fccf JB |
219 | dev_kfree_skb(skb); |
220 | return RX_QUEUED; | |
221 | } | |
222 | ||
4d36ec58 JB |
223 | /* return false if no more work */ |
224 | static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) | |
225 | { | |
226 | struct cfg80211_scan_request *req = local->scan_req; | |
227 | enum ieee80211_band band; | |
228 | int i, ielen, n_chans; | |
229 | ||
230 | do { | |
231 | if (local->hw_scan_band == IEEE80211_NUM_BANDS) | |
232 | return false; | |
233 | ||
234 | band = local->hw_scan_band; | |
235 | n_chans = 0; | |
236 | for (i = 0; i < req->n_channels; i++) { | |
237 | if (req->channels[i]->band == band) { | |
238 | local->hw_scan_req->channels[n_chans] = | |
239 | req->channels[i]; | |
240 | n_chans++; | |
241 | } | |
242 | } | |
243 | ||
244 | local->hw_scan_band++; | |
245 | } while (!n_chans); | |
246 | ||
247 | local->hw_scan_req->n_channels = n_chans; | |
248 | ||
249 | ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, | |
8ee31080 | 250 | req->ie, req->ie_len, band, |
85a237fe | 251 | req->rates[band], 0); |
4d36ec58 | 252 | local->hw_scan_req->ie_len = ielen; |
dcd83976 | 253 | local->hw_scan_req->no_cck = req->no_cck; |
4d36ec58 JB |
254 | |
255 | return true; | |
256 | } | |
257 | ||
d07bfd8b | 258 | static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted, |
e229f844 | 259 | bool was_hw_scan) |
0a51b27e JB |
260 | { |
261 | struct ieee80211_local *local = hw_to_local(hw); | |
0a51b27e | 262 | |
e229f844 | 263 | lockdep_assert_held(&local->mtx); |
5bc75728 | 264 | |
6d3560d4 JB |
265 | /* |
266 | * It's ok to abort a not-yet-running scan (that | |
267 | * we have one at all will be verified by checking | |
268 | * local->scan_req next), but not to complete it | |
269 | * successfully. | |
270 | */ | |
271 | if (WARN_ON(!local->scanning && !aborted)) | |
272 | aborted = true; | |
5bc75728 | 273 | |
e229f844 | 274 | if (WARN_ON(!local->scan_req)) |
d07bfd8b | 275 | return; |
de95a54b | 276 | |
4d36ec58 | 277 | if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { |
6eb11a9a SG |
278 | int rc = drv_hw_scan(local, local->scan_sdata, local->hw_scan_req); |
279 | if (rc == 0) | |
d07bfd8b | 280 | return; |
4d36ec58 JB |
281 | } |
282 | ||
283 | kfree(local->hw_scan_req); | |
284 | local->hw_scan_req = NULL; | |
f3b85252 | 285 | |
5ba63533 | 286 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
287 | cfg80211_scan_done(local->scan_req, aborted); |
288 | local->scan_req = NULL; | |
15db0b7f | 289 | local->scan_sdata = NULL; |
2a519311 | 290 | |
fbe9c429 | 291 | local->scanning = 0; |
58905ca5 | 292 | local->scan_channel = NULL; |
f3b85252 | 293 | |
07ef03ee JB |
294 | /* Set power back to normal operating levels. */ |
295 | ieee80211_hw_config(local, 0); | |
a0daa0e7 | 296 | |
e229f844 SG |
297 | if (!was_hw_scan) { |
298 | ieee80211_configure_filter(local); | |
299 | drv_sw_scan_complete(local); | |
e76aadc5 | 300 | ieee80211_offchannel_return(local, true); |
e229f844 | 301 | } |
0a51b27e | 302 | |
5cff20e6 | 303 | ieee80211_recalc_idle(local); |
e229f844 | 304 | |
0a51b27e | 305 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 306 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 307 | ieee80211_mesh_notify_scan_completed(local); |
81ac3462 | 308 | ieee80211_queue_work(&local->hw, &local->work_work); |
0a51b27e | 309 | } |
8789d459 JB |
310 | |
311 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) | |
312 | { | |
313 | struct ieee80211_local *local = hw_to_local(hw); | |
314 | ||
315 | trace_api_scan_completed(local, aborted); | |
316 | ||
317 | set_bit(SCAN_COMPLETED, &local->scanning); | |
318 | if (aborted) | |
319 | set_bit(SCAN_ABORTED, &local->scanning); | |
320 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); | |
321 | } | |
0a51b27e JB |
322 | EXPORT_SYMBOL(ieee80211_scan_completed); |
323 | ||
f3b85252 JB |
324 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
325 | { | |
f3b85252 JB |
326 | /* |
327 | * Hardware/driver doesn't support hw_scan, so use software | |
328 | * scanning instead. First send a nullfunc frame with power save | |
329 | * bit on so that AP will buffer the frames for us while we are not | |
330 | * listening, then send probe requests to each channel and wait for | |
331 | * the responses. After all channels are scanned, tune back to the | |
332 | * original channel and send a nullfunc frame with power save bit | |
333 | * off to trigger the AP to send us all the buffered frames. | |
334 | * | |
335 | * Note that while local->sw_scanning is true everything else but | |
336 | * nullfunc frames and probe requests will be dropped in | |
337 | * ieee80211_tx_h_check_assoc(). | |
338 | */ | |
24487981 | 339 | drv_sw_scan_start(local); |
f3b85252 | 340 | |
df13cce5 | 341 | local->leave_oper_channel_time = 0; |
977923b0 | 342 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
343 | local->scan_channel_idx = 0; |
344 | ||
07ef03ee | 345 | ieee80211_offchannel_stop_vifs(local, true); |
a80f7c0b | 346 | |
3ac64bee | 347 | ieee80211_configure_filter(local); |
f3b85252 | 348 | |
59bdf3b0 BG |
349 | /* We need to set power level at maximum rate for scanning. */ |
350 | ieee80211_hw_config(local, 0); | |
351 | ||
42935eca | 352 | ieee80211_queue_delayed_work(&local->hw, |
07ef03ee | 353 | &local->scan_work, 0); |
f3b85252 JB |
354 | |
355 | return 0; | |
356 | } | |
357 | ||
358 | ||
359 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
360 | struct cfg80211_scan_request *req) | |
361 | { | |
362 | struct ieee80211_local *local = sdata->local; | |
f3b85252 JB |
363 | int rc; |
364 | ||
e229f844 SG |
365 | lockdep_assert_held(&local->mtx); |
366 | ||
f3b85252 JB |
367 | if (local->scan_req) |
368 | return -EBUSY; | |
369 | ||
6e7e6213 JL |
370 | if (!list_empty(&local->work_list)) { |
371 | /* wait for the work to finish/time out */ | |
c0ce77b8 JB |
372 | local->scan_req = req; |
373 | local->scan_sdata = sdata; | |
374 | return 0; | |
375 | } | |
376 | ||
f3b85252 JB |
377 | if (local->ops->hw_scan) { |
378 | u8 *ies; | |
f3b85252 | 379 | |
4d36ec58 JB |
380 | local->hw_scan_req = kmalloc( |
381 | sizeof(*local->hw_scan_req) + | |
382 | req->n_channels * sizeof(req->channels[0]) + | |
383 | 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + | |
384 | req->ie_len, GFP_KERNEL); | |
385 | if (!local->hw_scan_req) | |
f3b85252 JB |
386 | return -ENOMEM; |
387 | ||
4d36ec58 JB |
388 | local->hw_scan_req->ssids = req->ssids; |
389 | local->hw_scan_req->n_ssids = req->n_ssids; | |
390 | ies = (u8 *)local->hw_scan_req + | |
391 | sizeof(*local->hw_scan_req) + | |
392 | req->n_channels * sizeof(req->channels[0]); | |
393 | local->hw_scan_req->ie = ies; | |
394 | ||
395 | local->hw_scan_band = 0; | |
6e7e6213 JL |
396 | |
397 | /* | |
398 | * After allocating local->hw_scan_req, we must | |
399 | * go through until ieee80211_prep_hw_scan(), so | |
400 | * anything that might be changed here and leave | |
401 | * this function early must not go after this | |
402 | * allocation. | |
403 | */ | |
f3b85252 JB |
404 | } |
405 | ||
406 | local->scan_req = req; | |
407 | local->scan_sdata = sdata; | |
408 | ||
f3b85252 | 409 | if (local->ops->hw_scan) |
fbe9c429 | 410 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 411 | else |
fbe9c429 | 412 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
6e7e6213 | 413 | |
5cff20e6 | 414 | ieee80211_recalc_idle(local); |
f3b85252 | 415 | |
4d36ec58 JB |
416 | if (local->ops->hw_scan) { |
417 | WARN_ON(!ieee80211_prep_hw_scan(local)); | |
a060bbfe | 418 | rc = drv_hw_scan(local, sdata, local->hw_scan_req); |
4d36ec58 | 419 | } else |
f3b85252 JB |
420 | rc = ieee80211_start_sw_scan(local); |
421 | ||
f3b85252 | 422 | if (rc) { |
4d36ec58 JB |
423 | kfree(local->hw_scan_req); |
424 | local->hw_scan_req = NULL; | |
fbe9c429 | 425 | local->scanning = 0; |
f3b85252 | 426 | |
5cff20e6 JB |
427 | ieee80211_recalc_idle(local); |
428 | ||
f3b85252 JB |
429 | local->scan_req = NULL; |
430 | local->scan_sdata = NULL; | |
431 | } | |
432 | ||
433 | return rc; | |
434 | } | |
435 | ||
df13cce5 HS |
436 | static unsigned long |
437 | ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) | |
438 | { | |
439 | /* | |
440 | * TODO: channel switching also consumes quite some time, | |
441 | * add that delay as well to get a better estimation | |
442 | */ | |
443 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) | |
444 | return IEEE80211_PASSIVE_CHANNEL_TIME; | |
445 | return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; | |
446 | } | |
447 | ||
e229f844 SG |
448 | static void ieee80211_scan_state_decision(struct ieee80211_local *local, |
449 | unsigned long *next_delay) | |
7d3be3cc | 450 | { |
142b9f50 | 451 | bool associated = false; |
df13cce5 HS |
452 | bool tx_empty = true; |
453 | bool bad_latency; | |
454 | bool listen_int_exceeded; | |
455 | unsigned long min_beacon_int = 0; | |
142b9f50 | 456 | struct ieee80211_sub_if_data *sdata; |
df13cce5 | 457 | struct ieee80211_channel *next_chan; |
142b9f50 | 458 | |
df13cce5 HS |
459 | /* |
460 | * check if at least one STA interface is associated, | |
461 | * check if at least one STA interface has pending tx frames | |
462 | * and grab the lowest used beacon interval | |
463 | */ | |
142b9f50 HS |
464 | mutex_lock(&local->iflist_mtx); |
465 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 466 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
467 | continue; |
468 | ||
469 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
470 | if (sdata->u.mgd.associated) { | |
471 | associated = true; | |
df13cce5 HS |
472 | |
473 | if (sdata->vif.bss_conf.beacon_int < | |
474 | min_beacon_int || min_beacon_int == 0) | |
475 | min_beacon_int = | |
476 | sdata->vif.bss_conf.beacon_int; | |
477 | ||
478 | if (!qdisc_all_tx_empty(sdata->dev)) { | |
479 | tx_empty = false; | |
480 | break; | |
481 | } | |
142b9f50 HS |
482 | } |
483 | } | |
484 | } | |
485 | mutex_unlock(&local->iflist_mtx); | |
486 | ||
b23b025f BG |
487 | next_chan = local->scan_req->channels[local->scan_channel_idx]; |
488 | ||
a80f7c0b | 489 | /* |
07ef03ee JB |
490 | * we're currently scanning a different channel, let's |
491 | * see if we can scan another channel without interfering | |
492 | * with the current traffic situation. | |
493 | * | |
494 | * Since we don't know if the AP has pending frames for us | |
495 | * we can only check for our tx queues and use the current | |
496 | * pm_qos requirements for rx. Hence, if no tx traffic occurs | |
497 | * at all we will scan as many channels in a row as the pm_qos | |
498 | * latency allows us to. Additionally we also check for the | |
499 | * currently negotiated listen interval to prevent losing | |
500 | * frames unnecessarily. | |
501 | * | |
502 | * Otherwise switch back to the operating channel. | |
a80f7c0b | 503 | */ |
a80f7c0b | 504 | |
07ef03ee JB |
505 | bad_latency = time_after(jiffies + |
506 | ieee80211_scan_get_channel_time(next_chan), | |
507 | local->leave_oper_channel_time + | |
508 | usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY))); | |
df13cce5 | 509 | |
07ef03ee JB |
510 | listen_int_exceeded = time_after(jiffies + |
511 | ieee80211_scan_get_channel_time(next_chan), | |
512 | local->leave_oper_channel_time + | |
513 | usecs_to_jiffies(min_beacon_int * 1024) * | |
514 | local->hw.conf.listen_interval); | |
142b9f50 | 515 | |
07ef03ee JB |
516 | if (associated && (!tx_empty || bad_latency || listen_int_exceeded)) |
517 | local->next_scan_state = SCAN_SUSPEND; | |
518 | else | |
519 | local->next_scan_state = SCAN_SET_CHANNEL; | |
142b9f50 | 520 | |
07ef03ee | 521 | *next_delay = 0; |
142b9f50 HS |
522 | } |
523 | ||
2fb3f028 HS |
524 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
525 | unsigned long *next_delay) | |
526 | { | |
527 | int skip; | |
528 | struct ieee80211_channel *chan; | |
2fb3f028 | 529 | |
7d3be3cc HS |
530 | skip = 0; |
531 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
532 | ||
584991dc | 533 | local->scan_channel = chan; |
b23b025f | 534 | |
07ef03ee JB |
535 | if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) |
536 | skip = 1; | |
7d3be3cc | 537 | |
7d3be3cc HS |
538 | /* advance state machine to next channel/band */ |
539 | local->scan_channel_idx++; | |
540 | ||
0ee9c13c HS |
541 | if (skip) { |
542 | /* if we skip this channel return to the decision state */ | |
543 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 544 | return; |
0ee9c13c | 545 | } |
7d3be3cc HS |
546 | |
547 | /* | |
548 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
549 | * (which unfortunately doesn't say _why_ step a) is done, | |
550 | * but it waits for the probe delay or until a frame is | |
551 | * received - and the received frame would update the NAV). | |
552 | * For now, we do not support waiting until a frame is | |
553 | * received. | |
554 | * | |
555 | * In any case, it is not necessary for a passive scan. | |
556 | */ | |
557 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
558 | !local->scan_req->n_ssids) { | |
559 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 560 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 561 | return; |
7d3be3cc HS |
562 | } |
563 | ||
2fb3f028 | 564 | /* active scan, send probes */ |
7d3be3cc | 565 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 566 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
567 | } |
568 | ||
569 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
570 | unsigned long *next_delay) | |
571 | { | |
572 | int i; | |
573 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
85a237fe | 574 | enum ieee80211_band band = local->hw.conf.channel->band; |
7d3be3cc HS |
575 | |
576 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
577 | ieee80211_send_probe_req( | |
578 | sdata, NULL, | |
579 | local->scan_req->ssids[i].ssid, | |
580 | local->scan_req->ssids[i].ssid_len, | |
a806c558 | 581 | local->scan_req->ie, local->scan_req->ie_len, |
aad14ceb RM |
582 | local->scan_req->rates[band], false, |
583 | local->scan_req->no_cck); | |
7d3be3cc HS |
584 | |
585 | /* | |
586 | * After sending probe requests, wait for probe responses | |
587 | * on the channel. | |
588 | */ | |
589 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 590 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
591 | } |
592 | ||
07ef03ee JB |
593 | static void ieee80211_scan_state_suspend(struct ieee80211_local *local, |
594 | unsigned long *next_delay) | |
595 | { | |
596 | /* switch back to the operating channel */ | |
597 | local->scan_channel = NULL; | |
598 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
599 | ||
600 | /* | |
601 | * Re-enable vifs and beaconing. Leave PS | |
602 | * in off-channel state..will put that back | |
603 | * on-channel at the end of scanning. | |
604 | */ | |
e76aadc5 | 605 | ieee80211_offchannel_return(local, false); |
07ef03ee JB |
606 | |
607 | *next_delay = HZ / 5; | |
608 | /* afterwards, resume scan & go to next channel */ | |
609 | local->next_scan_state = SCAN_RESUME; | |
610 | } | |
611 | ||
612 | static void ieee80211_scan_state_resume(struct ieee80211_local *local, | |
613 | unsigned long *next_delay) | |
614 | { | |
615 | /* PS already is in off-channel mode */ | |
616 | ieee80211_offchannel_stop_vifs(local, false); | |
617 | ||
618 | if (local->ops->flush) { | |
619 | drv_flush(local, false); | |
620 | *next_delay = 0; | |
621 | } else | |
622 | *next_delay = HZ / 10; | |
623 | ||
624 | /* remember when we left the operating channel */ | |
625 | local->leave_oper_channel_time = jiffies; | |
626 | ||
627 | /* advance to the next channel to be scanned */ | |
628 | local->next_scan_state = SCAN_DECISION; | |
629 | } | |
630 | ||
c2b13452 | 631 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
632 | { |
633 | struct ieee80211_local *local = | |
634 | container_of(work, struct ieee80211_local, scan_work.work); | |
d07bfd8b | 635 | struct ieee80211_sub_if_data *sdata; |
0a51b27e | 636 | unsigned long next_delay = 0; |
d07bfd8b | 637 | bool aborted, hw_scan; |
0a51b27e | 638 | |
259b62e3 | 639 | mutex_lock(&local->mtx); |
8789d459 | 640 | |
d07bfd8b JB |
641 | sdata = local->scan_sdata; |
642 | ||
259b62e3 | 643 | if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { |
8789d459 | 644 | aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); |
259b62e3 | 645 | goto out_complete; |
8789d459 JB |
646 | } |
647 | ||
259b62e3 SG |
648 | if (!sdata || !local->scan_req) |
649 | goto out; | |
f3b85252 | 650 | |
fbe9c429 | 651 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
652 | struct cfg80211_scan_request *req = local->scan_req; |
653 | int rc; | |
654 | ||
655 | local->scan_req = NULL; | |
15db0b7f | 656 | local->scan_sdata = NULL; |
f3b85252 JB |
657 | |
658 | rc = __ieee80211_start_scan(sdata, req); | |
259b62e3 | 659 | if (rc) { |
3aed49ef SG |
660 | /* need to complete scan in cfg80211 */ |
661 | local->scan_req = req; | |
259b62e3 SG |
662 | aborted = true; |
663 | goto out_complete; | |
664 | } else | |
665 | goto out; | |
f3b85252 JB |
666 | } |
667 | ||
5bc75728 JB |
668 | /* |
669 | * Avoid re-scheduling when the sdata is going away. | |
670 | */ | |
9607e6b6 | 671 | if (!ieee80211_sdata_running(sdata)) { |
259b62e3 SG |
672 | aborted = true; |
673 | goto out_complete; | |
f3b85252 | 674 | } |
0a51b27e | 675 | |
f502d09b HS |
676 | /* |
677 | * as long as no delay is required advance immediately | |
678 | * without scheduling a new work | |
679 | */ | |
680 | do { | |
c29acf20 RM |
681 | if (!ieee80211_sdata_running(sdata)) { |
682 | aborted = true; | |
683 | goto out_complete; | |
684 | } | |
685 | ||
977923b0 | 686 | switch (local->next_scan_state) { |
2fb3f028 | 687 | case SCAN_DECISION: |
e229f844 SG |
688 | /* if no more bands/channels left, complete scan */ |
689 | if (local->scan_channel_idx >= local->scan_req->n_channels) { | |
690 | aborted = false; | |
691 | goto out_complete; | |
692 | } | |
693 | ieee80211_scan_state_decision(local, &next_delay); | |
f502d09b | 694 | break; |
2fb3f028 HS |
695 | case SCAN_SET_CHANNEL: |
696 | ieee80211_scan_state_set_channel(local, &next_delay); | |
697 | break; | |
f502d09b HS |
698 | case SCAN_SEND_PROBE: |
699 | ieee80211_scan_state_send_probe(local, &next_delay); | |
700 | break; | |
07ef03ee JB |
701 | case SCAN_SUSPEND: |
702 | ieee80211_scan_state_suspend(local, &next_delay); | |
142b9f50 | 703 | break; |
07ef03ee JB |
704 | case SCAN_RESUME: |
705 | ieee80211_scan_state_resume(local, &next_delay); | |
142b9f50 | 706 | break; |
f502d09b HS |
707 | } |
708 | } while (next_delay == 0); | |
0a51b27e | 709 | |
42935eca | 710 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
d07bfd8b | 711 | goto out; |
259b62e3 SG |
712 | |
713 | out_complete: | |
e229f844 | 714 | hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
d07bfd8b | 715 | __ieee80211_scan_completed(&local->hw, aborted, hw_scan); |
259b62e3 SG |
716 | out: |
717 | mutex_unlock(&local->mtx); | |
0a51b27e JB |
718 | } |
719 | ||
f3b85252 JB |
720 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
721 | struct cfg80211_scan_request *req) | |
0a51b27e | 722 | { |
f3b85252 | 723 | int res; |
de95a54b | 724 | |
a1699b75 | 725 | mutex_lock(&sdata->local->mtx); |
f3b85252 | 726 | res = __ieee80211_start_scan(sdata, req); |
a1699b75 | 727 | mutex_unlock(&sdata->local->mtx); |
0a51b27e | 728 | |
f3b85252 | 729 | return res; |
0a51b27e JB |
730 | } |
731 | ||
f3b85252 | 732 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
be4a4b6a JB |
733 | const u8 *ssid, u8 ssid_len, |
734 | struct ieee80211_channel *chan) | |
0a51b27e | 735 | { |
0a51b27e | 736 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 737 | int ret = -EBUSY; |
fb63bc41 | 738 | enum ieee80211_band band; |
2a519311 | 739 | |
a1699b75 | 740 | mutex_lock(&local->mtx); |
0a51b27e | 741 | |
f3b85252 JB |
742 | /* busy scanning */ |
743 | if (local->scan_req) | |
744 | goto unlock; | |
9116dd01 | 745 | |
be4a4b6a JB |
746 | /* fill internal scan request */ |
747 | if (!chan) { | |
748 | int i, nchan = 0; | |
749 | ||
750 | for (band = 0; band < IEEE80211_NUM_BANDS; band++) { | |
751 | if (!local->hw.wiphy->bands[band]) | |
752 | continue; | |
753 | for (i = 0; | |
754 | i < local->hw.wiphy->bands[band]->n_channels; | |
755 | i++) { | |
756 | local->int_scan_req->channels[nchan] = | |
757 | &local->hw.wiphy->bands[band]->channels[i]; | |
758 | nchan++; | |
759 | } | |
760 | } | |
761 | ||
762 | local->int_scan_req->n_channels = nchan; | |
763 | } else { | |
764 | local->int_scan_req->channels[0] = chan; | |
765 | local->int_scan_req->n_channels = 1; | |
766 | } | |
767 | ||
768 | local->int_scan_req->ssids = &local->scan_ssid; | |
769 | local->int_scan_req->n_ssids = 1; | |
5ba63533 JB |
770 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
771 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 772 | |
5ba63533 | 773 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 | 774 | unlock: |
a1699b75 | 775 | mutex_unlock(&local->mtx); |
f3b85252 | 776 | return ret; |
0a51b27e | 777 | } |
5bb644a0 | 778 | |
4136c422 SG |
779 | /* |
780 | * Only call this function when a scan can't be queued -- under RTNL. | |
781 | */ | |
5bb644a0 JB |
782 | void ieee80211_scan_cancel(struct ieee80211_local *local) |
783 | { | |
5bb644a0 | 784 | /* |
b856439b | 785 | * We are canceling software scan, or deferred scan that was not |
4136c422 SG |
786 | * yet really started (see __ieee80211_start_scan ). |
787 | * | |
788 | * Regarding hardware scan: | |
789 | * - we can not call __ieee80211_scan_completed() as when | |
790 | * SCAN_HW_SCANNING bit is set this function change | |
791 | * local->hw_scan_req to operate on 5G band, what race with | |
792 | * driver which can use local->hw_scan_req | |
793 | * | |
794 | * - we can not cancel scan_work since driver can schedule it | |
795 | * by ieee80211_scan_completed(..., true) to finish scan | |
796 | * | |
b856439b EP |
797 | * Hence we only call the cancel_hw_scan() callback, but the low-level |
798 | * driver is still responsible for calling ieee80211_scan_completed() | |
799 | * after the scan was completed/aborted. | |
5bb644a0 | 800 | */ |
4136c422 | 801 | |
a1699b75 | 802 | mutex_lock(&local->mtx); |
b856439b EP |
803 | if (!local->scan_req) |
804 | goto out; | |
805 | ||
806 | if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { | |
807 | if (local->ops->cancel_hw_scan) | |
808 | drv_cancel_hw_scan(local, local->scan_sdata); | |
809 | goto out; | |
4136c422 | 810 | } |
b856439b EP |
811 | |
812 | /* | |
813 | * If the work is currently running, it must be blocked on | |
814 | * the mutex, but we'll set scan_sdata = NULL and it'll | |
815 | * simply exit once it acquires the mutex. | |
816 | */ | |
817 | cancel_delayed_work(&local->scan_work); | |
818 | /* and clean up */ | |
819 | __ieee80211_scan_completed(&local->hw, true, false); | |
820 | out: | |
d07bfd8b | 821 | mutex_unlock(&local->mtx); |
5bb644a0 | 822 | } |
79f460ca LC |
823 | |
824 | int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, | |
825 | struct cfg80211_sched_scan_request *req) | |
826 | { | |
827 | struct ieee80211_local *local = sdata->local; | |
828 | int ret, i; | |
829 | ||
830 | mutex_lock(&sdata->local->mtx); | |
831 | ||
832 | if (local->sched_scanning) { | |
833 | ret = -EBUSY; | |
834 | goto out; | |
835 | } | |
836 | ||
837 | if (!local->ops->sched_scan_start) { | |
838 | ret = -ENOTSUPP; | |
839 | goto out; | |
840 | } | |
841 | ||
842 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { | |
843 | local->sched_scan_ies.ie[i] = kzalloc(2 + | |
844 | IEEE80211_MAX_SSID_LEN + | |
1186980d LC |
845 | local->scan_ies_len + |
846 | req->ie_len, | |
79f460ca LC |
847 | GFP_KERNEL); |
848 | if (!local->sched_scan_ies.ie[i]) { | |
849 | ret = -ENOMEM; | |
850 | goto out_free; | |
851 | } | |
852 | ||
853 | local->sched_scan_ies.len[i] = | |
854 | ieee80211_build_preq_ies(local, | |
855 | local->sched_scan_ies.ie[i], | |
856 | req->ie, req->ie_len, i, | |
857 | (u32) -1, 0); | |
858 | } | |
859 | ||
860 | ret = drv_sched_scan_start(local, sdata, req, | |
861 | &local->sched_scan_ies); | |
862 | if (ret == 0) { | |
863 | local->sched_scanning = true; | |
864 | goto out; | |
865 | } | |
866 | ||
867 | out_free: | |
868 | while (i > 0) | |
869 | kfree(local->sched_scan_ies.ie[--i]); | |
870 | out: | |
871 | mutex_unlock(&sdata->local->mtx); | |
872 | return ret; | |
873 | } | |
874 | ||
85a9994a | 875 | int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata) |
79f460ca LC |
876 | { |
877 | struct ieee80211_local *local = sdata->local; | |
878 | int ret = 0, i; | |
879 | ||
880 | mutex_lock(&sdata->local->mtx); | |
881 | ||
882 | if (!local->ops->sched_scan_stop) { | |
883 | ret = -ENOTSUPP; | |
884 | goto out; | |
885 | } | |
886 | ||
887 | if (local->sched_scanning) { | |
888 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
889 | kfree(local->sched_scan_ies.ie[i]); | |
890 | ||
85a9994a | 891 | drv_sched_scan_stop(local, sdata); |
79f460ca LC |
892 | local->sched_scanning = false; |
893 | } | |
79f460ca LC |
894 | out: |
895 | mutex_unlock(&sdata->local->mtx); | |
896 | ||
897 | return ret; | |
898 | } | |
899 | ||
900 | void ieee80211_sched_scan_results(struct ieee80211_hw *hw) | |
901 | { | |
902 | struct ieee80211_local *local = hw_to_local(hw); | |
903 | ||
904 | trace_api_sched_scan_results(local); | |
905 | ||
906 | cfg80211_sched_scan_results(hw->wiphy); | |
907 | } | |
908 | EXPORT_SYMBOL(ieee80211_sched_scan_results); | |
909 | ||
85a9994a LC |
910 | void ieee80211_sched_scan_stopped_work(struct work_struct *work) |
911 | { | |
912 | struct ieee80211_local *local = | |
913 | container_of(work, struct ieee80211_local, | |
914 | sched_scan_stopped_work); | |
915 | int i; | |
916 | ||
917 | mutex_lock(&local->mtx); | |
918 | ||
919 | if (!local->sched_scanning) { | |
920 | mutex_unlock(&local->mtx); | |
921 | return; | |
922 | } | |
923 | ||
924 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
925 | kfree(local->sched_scan_ies.ie[i]); | |
926 | ||
927 | local->sched_scanning = false; | |
928 | ||
929 | mutex_unlock(&local->mtx); | |
930 | ||
931 | cfg80211_sched_scan_stopped(local->hw.wiphy); | |
932 | } | |
933 | ||
79f460ca LC |
934 | void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) |
935 | { | |
936 | struct ieee80211_local *local = hw_to_local(hw); | |
937 | ||
938 | trace_api_sched_scan_stopped(local); | |
939 | ||
85a9994a | 940 | ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work); |
79f460ca LC |
941 | } |
942 | EXPORT_SYMBOL(ieee80211_sched_scan_stopped); |