xref: /freebsd/sys/net80211/ieee80211_ht.c (revision 47dd1d1b619cc035b82b49a91a25544309ff95ae)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #ifdef __FreeBSD__
30 __FBSDID("$FreeBSD$");
31 #endif
32 
33 /*
34  * IEEE 802.11n protocol support.
35  */
36 
37 #include "opt_inet.h"
38 #include "opt_wlan.h"
39 
40 #include <sys/param.h>
41 #include <sys/kernel.h>
42 #include <sys/malloc.h>
43 #include <sys/systm.h>
44 #include <sys/endian.h>
45 
46 #include <sys/socket.h>
47 
48 #include <net/if.h>
49 #include <net/if_var.h>
50 #include <net/if_media.h>
51 #include <net/ethernet.h>
52 
53 #include <net80211/ieee80211_var.h>
54 #include <net80211/ieee80211_action.h>
55 #include <net80211/ieee80211_input.h>
56 
57 /* define here, used throughout file */
58 #define	MS(_v, _f)	(((_v) & _f) >> _f##_S)
59 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
60 
61 const struct ieee80211_mcs_rates ieee80211_htrates[IEEE80211_HTRATE_MAXSIZE] = {
62 	{  13,  14,   27,   30 },	/* MCS 0 */
63 	{  26,  29,   54,   60 },	/* MCS 1 */
64 	{  39,  43,   81,   90 },	/* MCS 2 */
65 	{  52,  58,  108,  120 },	/* MCS 3 */
66 	{  78,  87,  162,  180 },	/* MCS 4 */
67 	{ 104, 116,  216,  240 },	/* MCS 5 */
68 	{ 117, 130,  243,  270 },	/* MCS 6 */
69 	{ 130, 144,  270,  300 },	/* MCS 7 */
70 	{  26,  29,   54,   60 },	/* MCS 8 */
71 	{  52,  58,  108,  120 },	/* MCS 9 */
72 	{  78,  87,  162,  180 },	/* MCS 10 */
73 	{ 104, 116,  216,  240 },	/* MCS 11 */
74 	{ 156, 173,  324,  360 },	/* MCS 12 */
75 	{ 208, 231,  432,  480 },	/* MCS 13 */
76 	{ 234, 260,  486,  540 },	/* MCS 14 */
77 	{ 260, 289,  540,  600 },	/* MCS 15 */
78 	{  39,  43,   81,   90 },	/* MCS 16 */
79 	{  78,  87,  162,  180 },	/* MCS 17 */
80 	{ 117, 130,  243,  270 },	/* MCS 18 */
81 	{ 156, 173,  324,  360 },	/* MCS 19 */
82 	{ 234, 260,  486,  540 },	/* MCS 20 */
83 	{ 312, 347,  648,  720 },	/* MCS 21 */
84 	{ 351, 390,  729,  810 },	/* MCS 22 */
85 	{ 390, 433,  810,  900 },	/* MCS 23 */
86 	{  52,  58,  108,  120 },	/* MCS 24 */
87 	{ 104, 116,  216,  240 },	/* MCS 25 */
88 	{ 156, 173,  324,  360 },	/* MCS 26 */
89 	{ 208, 231,  432,  480 },	/* MCS 27 */
90 	{ 312, 347,  648,  720 },	/* MCS 28 */
91 	{ 416, 462,  864,  960 },	/* MCS 29 */
92 	{ 468, 520,  972, 1080 },	/* MCS 30 */
93 	{ 520, 578, 1080, 1200 },	/* MCS 31 */
94 	{   0,   0,   12,   13 },	/* MCS 32 */
95 	{  78,  87,  162,  180 },	/* MCS 33 */
96 	{ 104, 116,  216,  240 },	/* MCS 34 */
97 	{ 130, 144,  270,  300 },	/* MCS 35 */
98 	{ 117, 130,  243,  270 },	/* MCS 36 */
99 	{ 156, 173,  324,  360 },	/* MCS 37 */
100 	{ 195, 217,  405,  450 },	/* MCS 38 */
101 	{ 104, 116,  216,  240 },	/* MCS 39 */
102 	{ 130, 144,  270,  300 },	/* MCS 40 */
103 	{ 130, 144,  270,  300 },	/* MCS 41 */
104 	{ 156, 173,  324,  360 },	/* MCS 42 */
105 	{ 182, 202,  378,  420 },	/* MCS 43 */
106 	{ 182, 202,  378,  420 },	/* MCS 44 */
107 	{ 208, 231,  432,  480 },	/* MCS 45 */
108 	{ 156, 173,  324,  360 },	/* MCS 46 */
109 	{ 195, 217,  405,  450 },	/* MCS 47 */
110 	{ 195, 217,  405,  450 },	/* MCS 48 */
111 	{ 234, 260,  486,  540 },	/* MCS 49 */
112 	{ 273, 303,  567,  630 },	/* MCS 50 */
113 	{ 273, 303,  567,  630 },	/* MCS 51 */
114 	{ 312, 347,  648,  720 },	/* MCS 52 */
115 	{ 130, 144,  270,  300 },	/* MCS 53 */
116 	{ 156, 173,  324,  360 },	/* MCS 54 */
117 	{ 182, 202,  378,  420 },	/* MCS 55 */
118 	{ 156, 173,  324,  360 },	/* MCS 56 */
119 	{ 182, 202,  378,  420 },	/* MCS 57 */
120 	{ 208, 231,  432,  480 },	/* MCS 58 */
121 	{ 234, 260,  486,  540 },	/* MCS 59 */
122 	{ 208, 231,  432,  480 },	/* MCS 60 */
123 	{ 234, 260,  486,  540 },	/* MCS 61 */
124 	{ 260, 289,  540,  600 },	/* MCS 62 */
125 	{ 260, 289,  540,  600 },	/* MCS 63 */
126 	{ 286, 318,  594,  660 },	/* MCS 64 */
127 	{ 195, 217,  405,  450 },	/* MCS 65 */
128 	{ 234, 260,  486,  540 },	/* MCS 66 */
129 	{ 273, 303,  567,  630 },	/* MCS 67 */
130 	{ 234, 260,  486,  540 },	/* MCS 68 */
131 	{ 273, 303,  567,  630 },	/* MCS 69 */
132 	{ 312, 347,  648,  720 },	/* MCS 70 */
133 	{ 351, 390,  729,  810 },	/* MCS 71 */
134 	{ 312, 347,  648,  720 },	/* MCS 72 */
135 	{ 351, 390,  729,  810 },	/* MCS 73 */
136 	{ 390, 433,  810,  900 },	/* MCS 74 */
137 	{ 390, 433,  810,  900 },	/* MCS 75 */
138 	{ 429, 477,  891,  990 },	/* MCS 76 */
139 };
140 
141 static	int ieee80211_ampdu_age = -1;	/* threshold for ampdu reorder q (ms) */
142 SYSCTL_PROC(_net_wlan, OID_AUTO, ampdu_age, CTLTYPE_INT | CTLFLAG_RW,
143 	&ieee80211_ampdu_age, 0, ieee80211_sysctl_msecs_ticks, "I",
144 	"AMPDU max reorder age (ms)");
145 
146 static	int ieee80211_recv_bar_ena = 1;
147 SYSCTL_INT(_net_wlan, OID_AUTO, recv_bar, CTLFLAG_RW, &ieee80211_recv_bar_ena,
148 	    0, "BAR frame processing (ena/dis)");
149 
150 static	int ieee80211_addba_timeout = -1;/* timeout for ADDBA response */
151 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_timeout, CTLTYPE_INT | CTLFLAG_RW,
152 	&ieee80211_addba_timeout, 0, ieee80211_sysctl_msecs_ticks, "I",
153 	"ADDBA request timeout (ms)");
154 static	int ieee80211_addba_backoff = -1;/* backoff after max ADDBA requests */
155 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_backoff, CTLTYPE_INT | CTLFLAG_RW,
156 	&ieee80211_addba_backoff, 0, ieee80211_sysctl_msecs_ticks, "I",
157 	"ADDBA request backoff (ms)");
158 static	int ieee80211_addba_maxtries = 3;/* max ADDBA requests before backoff */
159 SYSCTL_INT(_net_wlan, OID_AUTO, addba_maxtries, CTLFLAG_RW,
160 	&ieee80211_addba_maxtries, 0, "max ADDBA requests sent before backoff");
161 
162 static	int ieee80211_bar_timeout = -1;	/* timeout waiting for BAR response */
163 static	int ieee80211_bar_maxtries = 50;/* max BAR requests before DELBA */
164 
165 static	ieee80211_recv_action_func ht_recv_action_ba_addba_request;
166 static	ieee80211_recv_action_func ht_recv_action_ba_addba_response;
167 static	ieee80211_recv_action_func ht_recv_action_ba_delba;
168 static	ieee80211_recv_action_func ht_recv_action_ht_mimopwrsave;
169 static	ieee80211_recv_action_func ht_recv_action_ht_txchwidth;
170 
171 static	ieee80211_send_action_func ht_send_action_ba_addba;
172 static	ieee80211_send_action_func ht_send_action_ba_delba;
173 static	ieee80211_send_action_func ht_send_action_ht_txchwidth;
174 
175 static void
176 ieee80211_ht_init(void)
177 {
178 	/*
179 	 * Setup HT parameters that depends on the clock frequency.
180 	 */
181 	ieee80211_ampdu_age = msecs_to_ticks(500);
182 	ieee80211_addba_timeout = msecs_to_ticks(250);
183 	ieee80211_addba_backoff = msecs_to_ticks(10*1000);
184 	ieee80211_bar_timeout = msecs_to_ticks(250);
185 	/*
186 	 * Register action frame handlers.
187 	 */
188 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
189 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_recv_action_ba_addba_request);
190 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
191 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_recv_action_ba_addba_response);
192 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
193 	    IEEE80211_ACTION_BA_DELBA, ht_recv_action_ba_delba);
194 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
195 	    IEEE80211_ACTION_HT_MIMOPWRSAVE, ht_recv_action_ht_mimopwrsave);
196 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
197 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_recv_action_ht_txchwidth);
198 
199 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
200 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_send_action_ba_addba);
201 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
202 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_send_action_ba_addba);
203 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
204 	    IEEE80211_ACTION_BA_DELBA, ht_send_action_ba_delba);
205 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_HT,
206 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_send_action_ht_txchwidth);
207 }
208 SYSINIT(wlan_ht, SI_SUB_DRIVERS, SI_ORDER_FIRST, ieee80211_ht_init, NULL);
209 
210 static int ieee80211_ampdu_enable(struct ieee80211_node *ni,
211 	struct ieee80211_tx_ampdu *tap);
212 static int ieee80211_addba_request(struct ieee80211_node *ni,
213 	struct ieee80211_tx_ampdu *tap,
214 	int dialogtoken, int baparamset, int batimeout);
215 static int ieee80211_addba_response(struct ieee80211_node *ni,
216 	struct ieee80211_tx_ampdu *tap,
217 	int code, int baparamset, int batimeout);
218 static void ieee80211_addba_stop(struct ieee80211_node *ni,
219 	struct ieee80211_tx_ampdu *tap);
220 static void null_addba_response_timeout(struct ieee80211_node *ni,
221 	struct ieee80211_tx_ampdu *tap);
222 
223 static void ieee80211_bar_response(struct ieee80211_node *ni,
224 	struct ieee80211_tx_ampdu *tap, int status);
225 static void ampdu_tx_stop(struct ieee80211_tx_ampdu *tap);
226 static void bar_stop_timer(struct ieee80211_tx_ampdu *tap);
227 static int ampdu_rx_start(struct ieee80211_node *, struct ieee80211_rx_ampdu *,
228 	int baparamset, int batimeout, int baseqctl);
229 static void ampdu_rx_stop(struct ieee80211_node *, struct ieee80211_rx_ampdu *);
230 
231 void
232 ieee80211_ht_attach(struct ieee80211com *ic)
233 {
234 	/* setup default aggregation policy */
235 	ic->ic_recv_action = ieee80211_recv_action;
236 	ic->ic_send_action = ieee80211_send_action;
237 	ic->ic_ampdu_enable = ieee80211_ampdu_enable;
238 	ic->ic_addba_request = ieee80211_addba_request;
239 	ic->ic_addba_response = ieee80211_addba_response;
240 	ic->ic_addba_response_timeout = null_addba_response_timeout;
241 	ic->ic_addba_stop = ieee80211_addba_stop;
242 	ic->ic_bar_response = ieee80211_bar_response;
243 	ic->ic_ampdu_rx_start = ampdu_rx_start;
244 	ic->ic_ampdu_rx_stop = ampdu_rx_stop;
245 
246 	ic->ic_htprotmode = IEEE80211_PROT_RTSCTS;
247 	ic->ic_curhtprotmode = IEEE80211_HTINFO_OPMODE_PURE;
248 }
249 
250 void
251 ieee80211_ht_detach(struct ieee80211com *ic)
252 {
253 }
254 
255 void
256 ieee80211_ht_vattach(struct ieee80211vap *vap)
257 {
258 
259 	/* driver can override defaults */
260 	vap->iv_ampdu_rxmax = IEEE80211_HTCAP_MAXRXAMPDU_8K;
261 	vap->iv_ampdu_density = IEEE80211_HTCAP_MPDUDENSITY_NA;
262 	vap->iv_ampdu_limit = vap->iv_ampdu_rxmax;
263 	vap->iv_amsdu_limit = vap->iv_htcaps & IEEE80211_HTCAP_MAXAMSDU;
264 	/* tx aggregation traffic thresholds */
265 	vap->iv_ampdu_mintraffic[WME_AC_BK] = 128;
266 	vap->iv_ampdu_mintraffic[WME_AC_BE] = 64;
267 	vap->iv_ampdu_mintraffic[WME_AC_VO] = 32;
268 	vap->iv_ampdu_mintraffic[WME_AC_VI] = 32;
269 
270 	if (vap->iv_htcaps & IEEE80211_HTC_HT) {
271 		/*
272 		 * Device is HT capable; enable all HT-related
273 		 * facilities by default.
274 		 * XXX these choices may be too aggressive.
275 		 */
276 		vap->iv_flags_ht |= IEEE80211_FHT_HT
277 				 |  IEEE80211_FHT_HTCOMPAT
278 				 ;
279 		if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI20)
280 			vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI20;
281 		/* XXX infer from channel list? */
282 		if (vap->iv_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
283 			vap->iv_flags_ht |= IEEE80211_FHT_USEHT40;
284 			if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI40)
285 				vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI40;
286 		}
287 		/* enable RIFS if capable */
288 		if (vap->iv_htcaps & IEEE80211_HTC_RIFS)
289 			vap->iv_flags_ht |= IEEE80211_FHT_RIFS;
290 
291 		/* NB: A-MPDU and A-MSDU rx are mandated, these are tx only */
292 		vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_RX;
293 		if (vap->iv_htcaps & IEEE80211_HTC_AMPDU)
294 			vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_TX;
295 		vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_RX;
296 		if (vap->iv_htcaps & IEEE80211_HTC_AMSDU)
297 			vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_TX;
298 
299 		if (vap->iv_htcaps & IEEE80211_HTCAP_TXSTBC)
300 			vap->iv_flags_ht |= IEEE80211_FHT_STBC_TX;
301 		if (vap->iv_htcaps & IEEE80211_HTCAP_RXSTBC)
302 			vap->iv_flags_ht |= IEEE80211_FHT_STBC_RX;
303 
304 		if (vap->iv_htcaps & IEEE80211_HTCAP_LDPC)
305 			vap->iv_flags_ht |= IEEE80211_FHT_LDPC_RX;
306 		if (vap->iv_htcaps & IEEE80211_HTC_TXLDPC)
307 			vap->iv_flags_ht |= IEEE80211_FHT_LDPC_TX;
308 	}
309 	/* NB: disable default legacy WDS, too many issues right now */
310 	if (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)
311 		vap->iv_flags_ht &= ~IEEE80211_FHT_HT;
312 }
313 
314 void
315 ieee80211_ht_vdetach(struct ieee80211vap *vap)
316 {
317 }
318 
319 static int
320 ht_getrate(struct ieee80211com *ic, int index, enum ieee80211_phymode mode,
321     int ratetype)
322 {
323 	int mword, rate;
324 
325 	mword = ieee80211_rate2media(ic, index | IEEE80211_RATE_MCS, mode);
326 	if (IFM_SUBTYPE(mword) != IFM_IEEE80211_MCS)
327 		return (0);
328 	switch (ratetype) {
329 	case 0:
330 		rate = ieee80211_htrates[index].ht20_rate_800ns;
331 		break;
332 	case 1:
333 		rate = ieee80211_htrates[index].ht20_rate_400ns;
334 		break;
335 	case 2:
336 		rate = ieee80211_htrates[index].ht40_rate_800ns;
337 		break;
338 	default:
339 		rate = ieee80211_htrates[index].ht40_rate_400ns;
340 		break;
341 	}
342 	return (rate);
343 }
344 
345 static struct printranges {
346 	int	minmcs;
347 	int	maxmcs;
348 	int	txstream;
349 	int	ratetype;
350 	int	htcapflags;
351 } ranges[] = {
352 	{  0,  7, 1, 0, 0 },
353 	{  8, 15, 2, 0, 0 },
354 	{ 16, 23, 3, 0, 0 },
355 	{ 24, 31, 4, 0, 0 },
356 	{ 32,  0, 1, 2, IEEE80211_HTC_TXMCS32 },
357 	{ 33, 38, 2, 0, IEEE80211_HTC_TXUNEQUAL },
358 	{ 39, 52, 3, 0, IEEE80211_HTC_TXUNEQUAL },
359 	{ 53, 76, 4, 0, IEEE80211_HTC_TXUNEQUAL },
360 	{  0,  0, 0, 0, 0 },
361 };
362 
363 static void
364 ht_rateprint(struct ieee80211com *ic, enum ieee80211_phymode mode, int ratetype)
365 {
366 	int minrate, maxrate;
367 	struct printranges *range;
368 
369 	for (range = ranges; range->txstream != 0; range++) {
370 		if (ic->ic_txstream < range->txstream)
371 			continue;
372 		if (range->htcapflags &&
373 		    (ic->ic_htcaps & range->htcapflags) == 0)
374 			continue;
375 		if (ratetype < range->ratetype)
376 			continue;
377 		minrate = ht_getrate(ic, range->minmcs, mode, ratetype);
378 		maxrate = ht_getrate(ic, range->maxmcs, mode, ratetype);
379 		if (range->maxmcs) {
380 			ic_printf(ic, "MCS %d-%d: %d%sMbps - %d%sMbps\n",
381 			    range->minmcs, range->maxmcs,
382 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""),
383 			    maxrate/2, ((maxrate & 0x1) != 0 ? ".5" : ""));
384 		} else {
385 			ic_printf(ic, "MCS %d: %d%sMbps\n", range->minmcs,
386 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""));
387 		}
388 	}
389 }
390 
391 static void
392 ht_announce(struct ieee80211com *ic, enum ieee80211_phymode mode)
393 {
394 	const char *modestr = ieee80211_phymode_name[mode];
395 
396 	ic_printf(ic, "%s MCS 20MHz\n", modestr);
397 	ht_rateprint(ic, mode, 0);
398 	if (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20) {
399 		ic_printf(ic, "%s MCS 20MHz SGI\n", modestr);
400 		ht_rateprint(ic, mode, 1);
401 	}
402 	if (ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
403 		ic_printf(ic, "%s MCS 40MHz:\n", modestr);
404 		ht_rateprint(ic, mode, 2);
405 	}
406 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
407 	    (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40)) {
408 		ic_printf(ic, "%s MCS 40MHz SGI:\n", modestr);
409 		ht_rateprint(ic, mode, 3);
410 	}
411 }
412 
413 void
414 ieee80211_ht_announce(struct ieee80211com *ic)
415 {
416 
417 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA) ||
418 	    isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
419 		ic_printf(ic, "%dT%dR\n", ic->ic_txstream, ic->ic_rxstream);
420 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
421 		ht_announce(ic, IEEE80211_MODE_11NA);
422 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
423 		ht_announce(ic, IEEE80211_MODE_11NG);
424 }
425 
426 void
427 ieee80211_init_suphtrates(struct ieee80211com *ic)
428 {
429 #define	ADDRATE(x)	do {						\
430 	htrateset->rs_rates[htrateset->rs_nrates] = x;			\
431 	htrateset->rs_nrates++;						\
432 } while (0)
433 	struct ieee80211_htrateset *htrateset = &ic->ic_sup_htrates;
434 	int i;
435 
436 	memset(htrateset, 0, sizeof(struct ieee80211_htrateset));
437 	for (i = 0; i < ic->ic_txstream * 8; i++)
438 		ADDRATE(i);
439 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
440 	    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32))
441 		ADDRATE(32);
442 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
443 		if (ic->ic_txstream >= 2) {
444 			 for (i = 33; i <= 38; i++)
445 				ADDRATE(i);
446 		}
447 		if (ic->ic_txstream >= 3) {
448 			for (i = 39; i <= 52; i++)
449 				ADDRATE(i);
450 		}
451 		if (ic->ic_txstream == 4) {
452 			for (i = 53; i <= 76; i++)
453 				ADDRATE(i);
454 		}
455 	}
456 #undef	ADDRATE
457 }
458 
459 /*
460  * Receive processing.
461  */
462 
463 /*
464  * Decap the encapsulated A-MSDU frames and dispatch all but
465  * the last for delivery.  The last frame is returned for
466  * delivery via the normal path.
467  */
468 struct mbuf *
469 ieee80211_decap_amsdu(struct ieee80211_node *ni, struct mbuf *m)
470 {
471 	struct ieee80211vap *vap = ni->ni_vap;
472 	int framelen;
473 	struct mbuf *n;
474 
475 	/* discard 802.3 header inserted by ieee80211_decap */
476 	m_adj(m, sizeof(struct ether_header));
477 
478 	vap->iv_stats.is_amsdu_decap++;
479 
480 	for (;;) {
481 		/*
482 		 * Decap the first frame, bust it apart from the
483 		 * remainder and deliver.  We leave the last frame
484 		 * delivery to the caller (for consistency with other
485 		 * code paths, could also do it here).
486 		 */
487 		m = ieee80211_decap1(m, &framelen);
488 		if (m == NULL) {
489 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
490 			    ni->ni_macaddr, "a-msdu", "%s", "decap failed");
491 			vap->iv_stats.is_amsdu_tooshort++;
492 			return NULL;
493 		}
494 		if (m->m_pkthdr.len == framelen)
495 			break;
496 		n = m_split(m, framelen, M_NOWAIT);
497 		if (n == NULL) {
498 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
499 			    ni->ni_macaddr, "a-msdu",
500 			    "%s", "unable to split encapsulated frames");
501 			vap->iv_stats.is_amsdu_split++;
502 			m_freem(m);			/* NB: must reclaim */
503 			return NULL;
504 		}
505 		vap->iv_deliver_data(vap, ni, m);
506 
507 		/*
508 		 * Remove frame contents; each intermediate frame
509 		 * is required to be aligned to a 4-byte boundary.
510 		 */
511 		m = n;
512 		m_adj(m, roundup2(framelen, 4) - framelen);	/* padding */
513 	}
514 	return m;				/* last delivered by caller */
515 }
516 
517 /*
518  * Add the given frame to the current RX reorder slot.
519  *
520  * For future offloaded A-MSDU handling where multiple frames with
521  * the same sequence number show up here, this routine will append
522  * those frames as long as they're appropriately tagged.
523  */
524 static int
525 ampdu_rx_add_slot(struct ieee80211_rx_ampdu *rap, int off, int tid,
526     ieee80211_seq rxseq,
527     struct ieee80211_node *ni,
528     struct mbuf *m)
529 {
530 	struct ieee80211vap *vap = ni->ni_vap;
531 
532 	if (rap->rxa_m[off] == NULL) {
533 		rap->rxa_m[off] = m;
534 		rap->rxa_qframes++;
535 		rap->rxa_qbytes += m->m_pkthdr.len;
536 		vap->iv_stats.is_ampdu_rx_reorder++;
537 		return (0);
538 	} else {
539 		IEEE80211_DISCARD_MAC(vap,
540 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
541 		    ni->ni_macaddr, "a-mpdu duplicate",
542 		    "seqno %u tid %u BA win <%u:%u>",
543 		    rxseq, tid, rap->rxa_start,
544 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1));
545 		vap->iv_stats.is_rx_dup++;
546 		IEEE80211_NODE_STAT(ni, rx_dup);
547 		m_freem(m);
548 		return (-1);
549 	}
550 }
551 
552 static void
553 ampdu_rx_purge_slot(struct ieee80211_rx_ampdu *rap, int i)
554 {
555 	struct mbuf *m;
556 
557 	m = rap->rxa_m[i];
558 	if (m == NULL)
559 		return;
560 
561 	rap->rxa_m[i] = NULL;
562 	rap->rxa_qbytes -= m->m_pkthdr.len;
563 	rap->rxa_qframes--;
564 	m_freem(m);
565 }
566 
567 /*
568  * Purge all frames in the A-MPDU re-order queue.
569  */
570 static void
571 ampdu_rx_purge(struct ieee80211_rx_ampdu *rap)
572 {
573 	int i;
574 
575 	for (i = 0; i < rap->rxa_wnd; i++) {
576 		ampdu_rx_purge_slot(rap, i);
577 		if (rap->rxa_qframes == 0)
578 			break;
579 	}
580 	KASSERT(rap->rxa_qbytes == 0 && rap->rxa_qframes == 0,
581 	    ("lost %u data, %u frames on ampdu rx q",
582 	    rap->rxa_qbytes, rap->rxa_qframes));
583 }
584 
585 /*
586  * Start A-MPDU rx/re-order processing for the specified TID.
587  */
588 static int
589 ampdu_rx_start(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap,
590 	int baparamset, int batimeout, int baseqctl)
591 {
592 	int bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
593 
594 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
595 		/*
596 		 * AMPDU previously setup and not terminated with a DELBA,
597 		 * flush the reorder q's in case anything remains.
598 		 */
599 		ampdu_rx_purge(rap);
600 	}
601 	memset(rap, 0, sizeof(*rap));
602 	rap->rxa_wnd = (bufsiz == 0) ?
603 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
604 	rap->rxa_start = MS(baseqctl, IEEE80211_BASEQ_START);
605 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
606 
607 	return 0;
608 }
609 
610 /*
611  * Public function; manually setup the RX ampdu state.
612  */
613 int
614 ieee80211_ampdu_rx_start_ext(struct ieee80211_node *ni, int tid, int seq, int baw)
615 {
616 	struct ieee80211_rx_ampdu *rap;
617 
618 	/* XXX TODO: sanity check tid, seq, baw */
619 
620 	rap = &ni->ni_rx_ampdu[tid];
621 
622 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
623 		/*
624 		 * AMPDU previously setup and not terminated with a DELBA,
625 		 * flush the reorder q's in case anything remains.
626 		 */
627 		ampdu_rx_purge(rap);
628 	}
629 
630 	memset(rap, 0, sizeof(*rap));
631 	rap->rxa_wnd = (baw== 0) ?
632 	    IEEE80211_AGGR_BAWMAX : min(baw, IEEE80211_AGGR_BAWMAX);
633 	if (seq == -1) {
634 		/* Wait for the first RX frame, use that as BAW */
635 		rap->rxa_start = 0;
636 		rap->rxa_flags |= IEEE80211_AGGR_WAITRX;
637 	} else {
638 		rap->rxa_start = seq;
639 	}
640 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
641 
642 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N, ni,
643 	    "%s: tid=%d, start=%d, wnd=%d, flags=0x%08x",
644 	    __func__,
645 	    tid,
646 	    seq,
647 	    rap->rxa_wnd,
648 	    rap->rxa_flags);
649 
650 	return 0;
651 }
652 
653 /*
654  * Public function; manually stop the RX AMPDU state.
655  */
656 void
657 ieee80211_ampdu_rx_stop_ext(struct ieee80211_node *ni, int tid)
658 {
659 	struct ieee80211_rx_ampdu *rap;
660 
661 	/* XXX TODO: sanity check tid, seq, baw */
662 	rap = &ni->ni_rx_ampdu[tid];
663 	ampdu_rx_stop(ni, rap);
664 }
665 
666 /*
667  * Stop A-MPDU rx processing for the specified TID.
668  */
669 static void
670 ampdu_rx_stop(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
671 {
672 
673 	ampdu_rx_purge(rap);
674 	rap->rxa_flags &= ~(IEEE80211_AGGR_RUNNING
675 	    | IEEE80211_AGGR_XCHGPEND
676 	    | IEEE80211_AGGR_WAITRX);
677 }
678 
679 /*
680  * Dispatch a frame from the A-MPDU reorder queue.  The
681  * frame is fed back into ieee80211_input marked with an
682  * M_AMPDU_MPDU flag so it doesn't come back to us (it also
683  * permits ieee80211_input to optimize re-processing).
684  */
685 static __inline void
686 ampdu_dispatch(struct ieee80211_node *ni, struct mbuf *m)
687 {
688 	m->m_flags |= M_AMPDU_MPDU;	/* bypass normal processing */
689 	/* NB: rssi and noise are ignored w/ M_AMPDU_MPDU set */
690 	(void) ieee80211_input(ni, m, 0, 0);
691 }
692 
693 static int
694 ampdu_dispatch_slot(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni,
695     int i)
696 {
697 	struct mbuf *m;
698 
699 	if (rap->rxa_m[i] == NULL)
700 		return (0);
701 
702 	m = rap->rxa_m[i];
703 	rap->rxa_m[i] = NULL;
704 	rap->rxa_qbytes -= m->m_pkthdr.len;
705 	rap->rxa_qframes--;
706 
707 	ampdu_dispatch(ni, m);
708 
709 	return (1);
710 }
711 
712 static void
713 ampdu_rx_moveup(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni,
714     int i, int winstart)
715 {
716 	struct ieee80211vap *vap = ni->ni_vap;
717 
718 	if (rap->rxa_qframes != 0) {
719 		int n = rap->rxa_qframes, j;
720 
721 		if (winstart != -1) {
722 			/*
723 			 * NB: in window-sliding mode, loop assumes i > 0
724 			 * and/or rxa_m[0] is NULL
725 			 */
726 			KASSERT(rap->rxa_m[0] == NULL,
727 			    ("%s: BA window slot 0 occupied", __func__));
728 		}
729 		for (j = i+1; j < rap->rxa_wnd; j++) {
730 			if (rap->rxa_m[j] != NULL) {
731 				rap->rxa_m[j-i] = rap->rxa_m[j];
732 				rap->rxa_m[j] = NULL;
733 				if (--n == 0)
734 					break;
735 			}
736 		}
737 		KASSERT(n == 0, ("%s: lost %d frames, qframes %d off %d "
738 		    "BA win <%d:%d> winstart %d",
739 		    __func__, n, rap->rxa_qframes, i, rap->rxa_start,
740 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
741 		    winstart));
742 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
743 	}
744 }
745 
746 /*
747  * Dispatch as many frames as possible from the re-order queue.
748  * Frames will always be "at the front"; we process all frames
749  * up to the first empty slot in the window.  On completion we
750  * cleanup state if there are still pending frames in the current
751  * BA window.  We assume the frame at slot 0 is already handled
752  * by the caller; we always start at slot 1.
753  */
754 static void
755 ampdu_rx_dispatch(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni)
756 {
757 	struct ieee80211vap *vap = ni->ni_vap;
758 	int i;
759 
760 	/* flush run of frames */
761 	for (i = 1; i < rap->rxa_wnd; i++) {
762 		if (ampdu_dispatch_slot(rap, ni, i) == 0)
763 			break;
764 	}
765 
766 	/*
767 	 * If frames remain, copy the mbuf pointers down so
768 	 * they correspond to the offsets in the new window.
769 	 */
770 	ampdu_rx_moveup(rap, ni, i, -1);
771 
772 	/*
773 	 * Adjust the start of the BA window to
774 	 * reflect the frames just dispatched.
775 	 */
776 	rap->rxa_start = IEEE80211_SEQ_ADD(rap->rxa_start, i);
777 	vap->iv_stats.is_ampdu_rx_oor += i;
778 }
779 
780 /*
781  * Dispatch all frames in the A-MPDU re-order queue.
782  */
783 static void
784 ampdu_rx_flush(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
785 {
786 	struct ieee80211vap *vap = ni->ni_vap;
787 	int i, r;
788 
789 	for (i = 0; i < rap->rxa_wnd; i++) {
790 		r = ampdu_dispatch_slot(rap, ni, i);
791 		if (r == 0)
792 			continue;
793 		vap->iv_stats.is_ampdu_rx_oor += r;
794 
795 		if (rap->rxa_qframes == 0)
796 			break;
797 	}
798 }
799 
800 /*
801  * Dispatch all frames in the A-MPDU re-order queue
802  * preceding the specified sequence number.  This logic
803  * handles window moves due to a received MSDU or BAR.
804  */
805 static void
806 ampdu_rx_flush_upto(struct ieee80211_node *ni,
807 	struct ieee80211_rx_ampdu *rap, ieee80211_seq winstart)
808 {
809 	struct ieee80211vap *vap = ni->ni_vap;
810 	ieee80211_seq seqno;
811 	int i, r;
812 
813 	/*
814 	 * Flush any complete MSDU's with a sequence number lower
815 	 * than winstart.  Gaps may exist.  Note that we may actually
816 	 * dispatch frames past winstart if a run continues; this is
817 	 * an optimization that avoids having to do a separate pass
818 	 * to dispatch frames after moving the BA window start.
819 	 */
820 	seqno = rap->rxa_start;
821 	for (i = 0; i < rap->rxa_wnd; i++) {
822 		r = ampdu_dispatch_slot(rap, ni, i);
823 		if (r == 0) {
824 			if (!IEEE80211_SEQ_BA_BEFORE(seqno, winstart))
825 				break;
826 		}
827 		vap->iv_stats.is_ampdu_rx_oor += r;
828 		seqno = IEEE80211_SEQ_INC(seqno);
829 	}
830 	/*
831 	 * If frames remain, copy the mbuf pointers down so
832 	 * they correspond to the offsets in the new window.
833 	 */
834 	ampdu_rx_moveup(rap, ni, i, winstart);
835 
836 	/*
837 	 * Move the start of the BA window; we use the
838 	 * sequence number of the last MSDU that was
839 	 * passed up the stack+1 or winstart if stopped on
840 	 * a gap in the reorder buffer.
841 	 */
842 	rap->rxa_start = seqno;
843 }
844 
845 /*
846  * Process a received QoS data frame for an HT station.  Handle
847  * A-MPDU reordering: if this frame is received out of order
848  * and falls within the BA window hold onto it.  Otherwise if
849  * this frame completes a run, flush any pending frames.  We
850  * return 1 if the frame is consumed.  A 0 is returned if
851  * the frame should be processed normally by the caller.
852  */
853 int
854 ieee80211_ampdu_reorder(struct ieee80211_node *ni, struct mbuf *m,
855     const struct ieee80211_rx_stats *rxs)
856 {
857 #define	PROCESS		0	/* caller should process frame */
858 #define	CONSUMED	1	/* frame consumed, caller does nothing */
859 	struct ieee80211vap *vap = ni->ni_vap;
860 	struct ieee80211_qosframe *wh;
861 	struct ieee80211_rx_ampdu *rap;
862 	ieee80211_seq rxseq;
863 	uint8_t tid;
864 	int off;
865 
866 	KASSERT((m->m_flags & (M_AMPDU | M_AMPDU_MPDU)) == M_AMPDU,
867 	    ("!a-mpdu or already re-ordered, flags 0x%x", m->m_flags));
868 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
869 
870 	/* NB: m_len known to be sufficient */
871 	wh = mtod(m, struct ieee80211_qosframe *);
872 	if (wh->i_fc[0] != IEEE80211_FC0_QOSDATA) {
873 		/*
874 		 * Not QoS data, shouldn't get here but just
875 		 * return it to the caller for processing.
876 		 */
877 		return PROCESS;
878 	}
879 
880 	/*
881 	 * 802.11-2012 9.3.2.10 - Duplicate detection and recovery.
882 	 *
883 	 * Multicast QoS data frames are checked against a different
884 	 * counter, not the per-TID counter.
885 	 */
886 	if (IEEE80211_IS_MULTICAST(wh->i_addr1))
887 		return PROCESS;
888 
889 	if (IEEE80211_IS_DSTODS(wh))
890 		tid = ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0];
891 	else
892 		tid = wh->i_qos[0];
893 	tid &= IEEE80211_QOS_TID;
894 	rap = &ni->ni_rx_ampdu[tid];
895 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
896 		/*
897 		 * No ADDBA request yet, don't touch.
898 		 */
899 		return PROCESS;
900 	}
901 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
902 	if ((rxseq & IEEE80211_SEQ_FRAG_MASK) != 0) {
903 		/*
904 		 * Fragments are not allowed; toss.
905 		 */
906 		IEEE80211_DISCARD_MAC(vap,
907 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
908 		    "A-MPDU", "fragment, rxseq 0x%x tid %u%s", rxseq, tid,
909 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
910 		vap->iv_stats.is_ampdu_rx_drop++;
911 		IEEE80211_NODE_STAT(ni, rx_drop);
912 		m_freem(m);
913 		return CONSUMED;
914 	}
915 	rxseq >>= IEEE80211_SEQ_SEQ_SHIFT;
916 	rap->rxa_nframes++;
917 
918 	/*
919 	 * Handle waiting for the first frame to define the BAW.
920 	 * Some firmware doesn't provide the RX of the starting point
921 	 * of the BAW and we have to cope.
922 	 */
923 	if (rap->rxa_flags & IEEE80211_AGGR_WAITRX) {
924 		rap->rxa_flags &= ~IEEE80211_AGGR_WAITRX;
925 		rap->rxa_start = rxseq;
926 	}
927 again:
928 	if (rxseq == rap->rxa_start) {
929 		/*
930 		 * First frame in window.
931 		 */
932 		if (rap->rxa_qframes != 0) {
933 			/*
934 			 * Dispatch as many packets as we can.
935 			 */
936 			KASSERT(rap->rxa_m[0] == NULL, ("unexpected dup"));
937 			ampdu_dispatch(ni, m);
938 			ampdu_rx_dispatch(rap, ni);
939 			return CONSUMED;
940 		} else {
941 			/*
942 			 * In order; advance window and notify
943 			 * caller to dispatch directly.
944 			 */
945 			rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
946 			return PROCESS;
947 		}
948 	}
949 	/*
950 	 * Frame is out of order; store if in the BA window.
951 	 */
952 	/* calculate offset in BA window */
953 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
954 	if (off < rap->rxa_wnd) {
955 		/*
956 		 * Common case (hopefully): in the BA window.
957 		 * Sec 9.10.7.6.2 a) (p.137)
958 		 */
959 
960 		/*
961 		 * Check for frames sitting too long in the reorder queue.
962 		 * This should only ever happen if frames are not delivered
963 		 * without the sender otherwise notifying us (e.g. with a
964 		 * BAR to move the window).  Typically this happens because
965 		 * of vendor bugs that cause the sequence number to jump.
966 		 * When this happens we get a gap in the reorder queue that
967 		 * leaves frame sitting on the queue until they get pushed
968 		 * out due to window moves.  When the vendor does not send
969 		 * BAR this move only happens due to explicit packet sends
970 		 *
971 		 * NB: we only track the time of the oldest frame in the
972 		 * reorder q; this means that if we flush we might push
973 		 * frames that still "new"; if this happens then subsequent
974 		 * frames will result in BA window moves which cost something
975 		 * but is still better than a big throughput dip.
976 		 */
977 		if (rap->rxa_qframes != 0) {
978 			/* XXX honor batimeout? */
979 			if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
980 				/*
981 				 * Too long since we received the first
982 				 * frame; flush the reorder buffer.
983 				 */
984 				if (rap->rxa_qframes != 0) {
985 					vap->iv_stats.is_ampdu_rx_age +=
986 					    rap->rxa_qframes;
987 					ampdu_rx_flush(ni, rap);
988 				}
989 				rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
990 				return PROCESS;
991 			}
992 		} else {
993 			/*
994 			 * First frame, start aging timer.
995 			 */
996 			rap->rxa_age = ticks;
997 		}
998 
999 		/* save packet - this consumes, no matter what */
1000 		ampdu_rx_add_slot(rap, off, tid, rxseq, ni, m);
1001 
1002 		return CONSUMED;
1003 	}
1004 	if (off < IEEE80211_SEQ_BA_RANGE) {
1005 		/*
1006 		 * Outside the BA window, but within range;
1007 		 * flush the reorder q and move the window.
1008 		 * Sec 9.10.7.6.2 b) (p.138)
1009 		 */
1010 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1011 		    "move BA win <%u:%u> (%u frames) rxseq %u tid %u",
1012 		    rap->rxa_start,
1013 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1014 		    rap->rxa_qframes, rxseq, tid);
1015 		vap->iv_stats.is_ampdu_rx_move++;
1016 
1017 		/*
1018 		 * The spec says to flush frames up to but not including:
1019 		 * 	WinStart_B = rxseq - rap->rxa_wnd + 1
1020 		 * Then insert the frame or notify the caller to process
1021 		 * it immediately.  We can safely do this by just starting
1022 		 * over again because we know the frame will now be within
1023 		 * the BA window.
1024 		 */
1025 		/* NB: rxa_wnd known to be >0 */
1026 		ampdu_rx_flush_upto(ni, rap,
1027 		    IEEE80211_SEQ_SUB(rxseq, rap->rxa_wnd-1));
1028 		goto again;
1029 	} else {
1030 		/*
1031 		 * Outside the BA window and out of range; toss.
1032 		 * Sec 9.10.7.6.2 c) (p.138)
1033 		 */
1034 		IEEE80211_DISCARD_MAC(vap,
1035 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
1036 		    "MPDU", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
1037 		    rap->rxa_start,
1038 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1039 		    rap->rxa_qframes, rxseq, tid,
1040 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
1041 		vap->iv_stats.is_ampdu_rx_drop++;
1042 		IEEE80211_NODE_STAT(ni, rx_drop);
1043 		m_freem(m);
1044 		return CONSUMED;
1045 	}
1046 #undef CONSUMED
1047 #undef PROCESS
1048 }
1049 
1050 /*
1051  * Process a BAR ctl frame.  Dispatch all frames up to
1052  * the sequence number of the frame.  If this frame is
1053  * out of range it's discarded.
1054  */
1055 void
1056 ieee80211_recv_bar(struct ieee80211_node *ni, struct mbuf *m0)
1057 {
1058 	struct ieee80211vap *vap = ni->ni_vap;
1059 	struct ieee80211_frame_bar *wh;
1060 	struct ieee80211_rx_ampdu *rap;
1061 	ieee80211_seq rxseq;
1062 	int tid, off;
1063 
1064 	if (!ieee80211_recv_bar_ena) {
1065 #if 0
1066 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_11N,
1067 		    ni->ni_macaddr, "BAR", "%s", "processing disabled");
1068 #endif
1069 		vap->iv_stats.is_ampdu_bar_bad++;
1070 		return;
1071 	}
1072 	wh = mtod(m0, struct ieee80211_frame_bar *);
1073 	/* XXX check basic BAR */
1074 	tid = MS(le16toh(wh->i_ctl), IEEE80211_BAR_TID);
1075 	rap = &ni->ni_rx_ampdu[tid];
1076 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
1077 		/*
1078 		 * No ADDBA request yet, don't touch.
1079 		 */
1080 		IEEE80211_DISCARD_MAC(vap,
1081 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
1082 		    ni->ni_macaddr, "BAR", "no BA stream, tid %u", tid);
1083 		vap->iv_stats.is_ampdu_bar_bad++;
1084 		return;
1085 	}
1086 	vap->iv_stats.is_ampdu_bar_rx++;
1087 	rxseq = le16toh(wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
1088 	if (rxseq == rap->rxa_start)
1089 		return;
1090 	/* calculate offset in BA window */
1091 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
1092 	if (off < IEEE80211_SEQ_BA_RANGE) {
1093 		/*
1094 		 * Flush the reorder q up to rxseq and move the window.
1095 		 * Sec 9.10.7.6.3 a) (p.138)
1096 		 */
1097 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1098 		    "BAR moves BA win <%u:%u> (%u frames) rxseq %u tid %u",
1099 		    rap->rxa_start,
1100 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1101 		    rap->rxa_qframes, rxseq, tid);
1102 		vap->iv_stats.is_ampdu_bar_move++;
1103 
1104 		ampdu_rx_flush_upto(ni, rap, rxseq);
1105 		if (off >= rap->rxa_wnd) {
1106 			/*
1107 			 * BAR specifies a window start to the right of BA
1108 			 * window; we must move it explicitly since
1109 			 * ampdu_rx_flush_upto will not.
1110 			 */
1111 			rap->rxa_start = rxseq;
1112 		}
1113 	} else {
1114 		/*
1115 		 * Out of range; toss.
1116 		 * Sec 9.10.7.6.3 b) (p.138)
1117 		 */
1118 		IEEE80211_DISCARD_MAC(vap,
1119 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
1120 		    "BAR", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
1121 		    rap->rxa_start,
1122 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1123 		    rap->rxa_qframes, rxseq, tid,
1124 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
1125 		vap->iv_stats.is_ampdu_bar_oow++;
1126 		IEEE80211_NODE_STAT(ni, rx_drop);
1127 	}
1128 }
1129 
1130 /*
1131  * Setup HT-specific state in a node.  Called only
1132  * when HT use is negotiated so we don't do extra
1133  * work for temporary and/or legacy sta's.
1134  */
1135 void
1136 ieee80211_ht_node_init(struct ieee80211_node *ni)
1137 {
1138 	struct ieee80211_tx_ampdu *tap;
1139 	int tid;
1140 
1141 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1142 	    ni,
1143 	    "%s: called (%p)",
1144 	    __func__,
1145 	    ni);
1146 
1147 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1148 		/*
1149 		 * Clean AMPDU state on re-associate.  This handles the case
1150 		 * where a station leaves w/o notifying us and then returns
1151 		 * before node is reaped for inactivity.
1152 		 */
1153 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1154 		    ni,
1155 		    "%s: calling cleanup (%p)",
1156 		    __func__, ni);
1157 		ieee80211_ht_node_cleanup(ni);
1158 	}
1159 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1160 		tap = &ni->ni_tx_ampdu[tid];
1161 		tap->txa_tid = tid;
1162 		tap->txa_ni = ni;
1163 		ieee80211_txampdu_init_pps(tap);
1164 		/* NB: further initialization deferred */
1165 	}
1166 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1167 }
1168 
1169 /*
1170  * Cleanup HT-specific state in a node.  Called only
1171  * when HT use has been marked.
1172  */
1173 void
1174 ieee80211_ht_node_cleanup(struct ieee80211_node *ni)
1175 {
1176 	struct ieee80211com *ic = ni->ni_ic;
1177 	int i;
1178 
1179 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1180 	    ni,
1181 	    "%s: called (%p)",
1182 	    __func__, ni);
1183 
1184 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT node"));
1185 
1186 	/* XXX optimize this */
1187 	for (i = 0; i < WME_NUM_TID; i++) {
1188 		struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[i];
1189 		if (tap->txa_flags & IEEE80211_AGGR_SETUP)
1190 			ampdu_tx_stop(tap);
1191 	}
1192 	for (i = 0; i < WME_NUM_TID; i++)
1193 		ic->ic_ampdu_rx_stop(ni, &ni->ni_rx_ampdu[i]);
1194 
1195 	ni->ni_htcap = 0;
1196 	ni->ni_flags &= ~IEEE80211_NODE_HT_ALL;
1197 }
1198 
1199 /*
1200  * Age out HT resources for a station.
1201  */
1202 void
1203 ieee80211_ht_node_age(struct ieee80211_node *ni)
1204 {
1205 	struct ieee80211vap *vap = ni->ni_vap;
1206 	uint8_t tid;
1207 
1208 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
1209 
1210 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1211 		struct ieee80211_rx_ampdu *rap;
1212 
1213 		rap = &ni->ni_rx_ampdu[tid];
1214 		if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0)
1215 			continue;
1216 		if (rap->rxa_qframes == 0)
1217 			continue;
1218 		/*
1219 		 * Check for frames sitting too long in the reorder queue.
1220 		 * See above for more details on what's happening here.
1221 		 */
1222 		/* XXX honor batimeout? */
1223 		if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
1224 			/*
1225 			 * Too long since we received the first
1226 			 * frame; flush the reorder buffer.
1227 			 */
1228 			vap->iv_stats.is_ampdu_rx_age += rap->rxa_qframes;
1229 			ampdu_rx_flush(ni, rap);
1230 		}
1231 	}
1232 }
1233 
1234 static struct ieee80211_channel *
1235 findhtchan(struct ieee80211com *ic, struct ieee80211_channel *c, int htflags)
1236 {
1237 	return ieee80211_find_channel(ic, c->ic_freq,
1238 	    (c->ic_flags &~ IEEE80211_CHAN_HT) | htflags);
1239 }
1240 
1241 /*
1242  * Adjust a channel to be HT/non-HT according to the vap's configuration.
1243  */
1244 struct ieee80211_channel *
1245 ieee80211_ht_adjust_channel(struct ieee80211com *ic,
1246 	struct ieee80211_channel *chan, int flags)
1247 {
1248 	struct ieee80211_channel *c;
1249 
1250 	if (flags & IEEE80211_FHT_HT) {
1251 		/* promote to HT if possible */
1252 		if (flags & IEEE80211_FHT_USEHT40) {
1253 			if (!IEEE80211_IS_CHAN_HT40(chan)) {
1254 				/* NB: arbitrarily pick ht40+ over ht40- */
1255 				c = findhtchan(ic, chan, IEEE80211_CHAN_HT40U);
1256 				if (c == NULL)
1257 					c = findhtchan(ic, chan,
1258 						IEEE80211_CHAN_HT40D);
1259 				if (c == NULL)
1260 					c = findhtchan(ic, chan,
1261 						IEEE80211_CHAN_HT20);
1262 				if (c != NULL)
1263 					chan = c;
1264 			}
1265 		} else if (!IEEE80211_IS_CHAN_HT20(chan)) {
1266 			c = findhtchan(ic, chan, IEEE80211_CHAN_HT20);
1267 			if (c != NULL)
1268 				chan = c;
1269 		}
1270 	} else if (IEEE80211_IS_CHAN_HT(chan)) {
1271 		/* demote to legacy, HT use is disabled */
1272 		c = ieee80211_find_channel(ic, chan->ic_freq,
1273 		    chan->ic_flags &~ IEEE80211_CHAN_HT);
1274 		if (c != NULL)
1275 			chan = c;
1276 	}
1277 	return chan;
1278 }
1279 
1280 /*
1281  * Setup HT-specific state for a legacy WDS peer.
1282  */
1283 void
1284 ieee80211_ht_wds_init(struct ieee80211_node *ni)
1285 {
1286 	struct ieee80211vap *vap = ni->ni_vap;
1287 	struct ieee80211_tx_ampdu *tap;
1288 	int tid;
1289 
1290 	KASSERT(vap->iv_flags_ht & IEEE80211_FHT_HT, ("no HT requested"));
1291 
1292 	/* XXX check scan cache in case peer has an ap and we have info */
1293 	/*
1294 	 * If setup with a legacy channel; locate an HT channel.
1295 	 * Otherwise if the inherited channel (from a companion
1296 	 * AP) is suitable use it so we use the same location
1297 	 * for the extension channel).
1298 	 */
1299 	ni->ni_chan = ieee80211_ht_adjust_channel(ni->ni_ic,
1300 	    ni->ni_chan, ieee80211_htchanflags(ni->ni_chan));
1301 
1302 	ni->ni_htcap = 0;
1303 	if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20)
1304 		ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI20;
1305 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan)) {
1306 		ni->ni_htcap |= IEEE80211_HTCAP_CHWIDTH40;
1307 		ni->ni_chw = 40;
1308 		if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
1309 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_ABOVE;
1310 		else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
1311 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_BELOW;
1312 		if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40)
1313 			ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI40;
1314 	} else {
1315 		ni->ni_chw = 20;
1316 		ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_NONE;
1317 	}
1318 	ni->ni_htctlchan = ni->ni_chan->ic_ieee;
1319 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
1320 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1321 	/* XXX does it make sense to enable SMPS? */
1322 
1323 	ni->ni_htopmode = 0;		/* XXX need protection state */
1324 	ni->ni_htstbc = 0;		/* XXX need info */
1325 
1326 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1327 		tap = &ni->ni_tx_ampdu[tid];
1328 		tap->txa_tid = tid;
1329 		ieee80211_txampdu_init_pps(tap);
1330 	}
1331 	/* NB: AMPDU tx/rx governed by IEEE80211_FHT_AMPDU_{TX,RX} */
1332 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1333 }
1334 
1335 /*
1336  * Notify hostap vaps of a change in the HTINFO ie.
1337  */
1338 static void
1339 htinfo_notify(struct ieee80211com *ic)
1340 {
1341 	struct ieee80211vap *vap;
1342 	int first = 1;
1343 
1344 	IEEE80211_LOCK_ASSERT(ic);
1345 
1346 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
1347 		if (vap->iv_opmode != IEEE80211_M_HOSTAP)
1348 			continue;
1349 		if (vap->iv_state != IEEE80211_S_RUN ||
1350 		    !IEEE80211_IS_CHAN_HT(vap->iv_bss->ni_chan))
1351 			continue;
1352 		if (first) {
1353 			IEEE80211_NOTE(vap,
1354 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1355 			    vap->iv_bss,
1356 			    "HT bss occupancy change: %d sta, %d ht, "
1357 			    "%d ht40%s, HT protmode now 0x%x"
1358 			    , ic->ic_sta_assoc
1359 			    , ic->ic_ht_sta_assoc
1360 			    , ic->ic_ht40_sta_assoc
1361 			    , (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) ?
1362 				 ", non-HT sta present" : ""
1363 			    , ic->ic_curhtprotmode);
1364 			first = 0;
1365 		}
1366 		ieee80211_beacon_notify(vap, IEEE80211_BEACON_HTINFO);
1367 	}
1368 }
1369 
1370 /*
1371  * Calculate HT protection mode from current
1372  * state and handle updates.
1373  */
1374 static void
1375 htinfo_update(struct ieee80211com *ic)
1376 {
1377 	uint8_t protmode;
1378 
1379 	if (ic->ic_sta_assoc != ic->ic_ht_sta_assoc) {
1380 		protmode = IEEE80211_HTINFO_OPMODE_MIXED
1381 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1382 	} else if (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) {
1383 		protmode = IEEE80211_HTINFO_OPMODE_PROTOPT
1384 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1385 	} else if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
1386 	    IEEE80211_IS_CHAN_HT40(ic->ic_bsschan) &&
1387 	    ic->ic_sta_assoc != ic->ic_ht40_sta_assoc) {
1388 		protmode = IEEE80211_HTINFO_OPMODE_HT20PR;
1389 	} else {
1390 		protmode = IEEE80211_HTINFO_OPMODE_PURE;
1391 	}
1392 	if (protmode != ic->ic_curhtprotmode) {
1393 		ic->ic_curhtprotmode = protmode;
1394 		htinfo_notify(ic);
1395 	}
1396 }
1397 
1398 /*
1399  * Handle an HT station joining a BSS.
1400  */
1401 void
1402 ieee80211_ht_node_join(struct ieee80211_node *ni)
1403 {
1404 	struct ieee80211com *ic = ni->ni_ic;
1405 
1406 	IEEE80211_LOCK_ASSERT(ic);
1407 
1408 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1409 		ic->ic_ht_sta_assoc++;
1410 		if (ni->ni_chw == 40)
1411 			ic->ic_ht40_sta_assoc++;
1412 	}
1413 	htinfo_update(ic);
1414 }
1415 
1416 /*
1417  * Handle an HT station leaving a BSS.
1418  */
1419 void
1420 ieee80211_ht_node_leave(struct ieee80211_node *ni)
1421 {
1422 	struct ieee80211com *ic = ni->ni_ic;
1423 
1424 	IEEE80211_LOCK_ASSERT(ic);
1425 
1426 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1427 		ic->ic_ht_sta_assoc--;
1428 		if (ni->ni_chw == 40)
1429 			ic->ic_ht40_sta_assoc--;
1430 	}
1431 	htinfo_update(ic);
1432 }
1433 
1434 /*
1435  * Public version of htinfo_update; used for processing
1436  * beacon frames from overlapping bss.
1437  *
1438  * Caller can specify either IEEE80211_HTINFO_OPMODE_MIXED
1439  * (on receipt of a beacon that advertises MIXED) or
1440  * IEEE80211_HTINFO_OPMODE_PROTOPT (on receipt of a beacon
1441  * from an overlapping legacy bss).  We treat MIXED with
1442  * a higher precedence than PROTOPT (i.e. we will not change
1443  * change PROTOPT -> MIXED; only MIXED -> PROTOPT).  This
1444  * corresponds to how we handle things in htinfo_update.
1445  */
1446 void
1447 ieee80211_htprot_update(struct ieee80211com *ic, int protmode)
1448 {
1449 #define	OPMODE(x)	SM(x, IEEE80211_HTINFO_OPMODE)
1450 	IEEE80211_LOCK(ic);
1451 
1452 	/* track non-HT station presence */
1453 	KASSERT(protmode & IEEE80211_HTINFO_NONHT_PRESENT,
1454 	    ("protmode 0x%x", protmode));
1455 	ic->ic_flags_ht |= IEEE80211_FHT_NONHT_PR;
1456 	ic->ic_lastnonht = ticks;
1457 
1458 	if (protmode != ic->ic_curhtprotmode &&
1459 	    (OPMODE(ic->ic_curhtprotmode) != IEEE80211_HTINFO_OPMODE_MIXED ||
1460 	     OPMODE(protmode) == IEEE80211_HTINFO_OPMODE_PROTOPT)) {
1461 		/* push beacon update */
1462 		ic->ic_curhtprotmode = protmode;
1463 		htinfo_notify(ic);
1464 	}
1465 	IEEE80211_UNLOCK(ic);
1466 #undef OPMODE
1467 }
1468 
1469 /*
1470  * Time out presence of an overlapping bss with non-HT
1471  * stations.  When operating in hostap mode we listen for
1472  * beacons from other stations and if we identify a non-HT
1473  * station is present we update the opmode field of the
1474  * HTINFO ie.  To identify when all non-HT stations are
1475  * gone we time out this condition.
1476  */
1477 void
1478 ieee80211_ht_timeout(struct ieee80211com *ic)
1479 {
1480 	IEEE80211_LOCK_ASSERT(ic);
1481 
1482 	if ((ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) &&
1483 	    ieee80211_time_after(ticks, ic->ic_lastnonht + IEEE80211_NONHT_PRESENT_AGE)) {
1484 #if 0
1485 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1486 		    "%s", "time out non-HT STA present on channel");
1487 #endif
1488 		ic->ic_flags_ht &= ~IEEE80211_FHT_NONHT_PR;
1489 		htinfo_update(ic);
1490 	}
1491 }
1492 
1493 /*
1494  * Process an 802.11n HT capabilities ie.
1495  */
1496 void
1497 ieee80211_parse_htcap(struct ieee80211_node *ni, const uint8_t *ie)
1498 {
1499 	if (ie[0] == IEEE80211_ELEMID_VENDOR) {
1500 		/*
1501 		 * Station used Vendor OUI ie to associate;
1502 		 * mark the node so when we respond we'll use
1503 		 * the Vendor OUI's and not the standard ie's.
1504 		 */
1505 		ni->ni_flags |= IEEE80211_NODE_HTCOMPAT;
1506 		ie += 4;
1507 	} else
1508 		ni->ni_flags &= ~IEEE80211_NODE_HTCOMPAT;
1509 
1510 	ni->ni_htcap = le16dec(ie +
1511 		__offsetof(struct ieee80211_ie_htcap, hc_cap));
1512 	ni->ni_htparam = ie[__offsetof(struct ieee80211_ie_htcap, hc_param)];
1513 }
1514 
1515 static void
1516 htinfo_parse(struct ieee80211_node *ni,
1517 	const struct ieee80211_ie_htinfo *htinfo)
1518 {
1519 	uint16_t w;
1520 
1521 	ni->ni_htctlchan = htinfo->hi_ctrlchannel;
1522 	ni->ni_ht2ndchan = SM(htinfo->hi_byte1, IEEE80211_HTINFO_2NDCHAN);
1523 	w = le16dec(&htinfo->hi_byte2);
1524 	ni->ni_htopmode = SM(w, IEEE80211_HTINFO_OPMODE);
1525 	w = le16dec(&htinfo->hi_byte45);
1526 	ni->ni_htstbc = SM(w, IEEE80211_HTINFO_BASIC_STBCMCS);
1527 }
1528 
1529 /*
1530  * Parse an 802.11n HT info ie and save useful information
1531  * to the node state.  Note this does not effect any state
1532  * changes such as for channel width change.
1533  */
1534 void
1535 ieee80211_parse_htinfo(struct ieee80211_node *ni, const uint8_t *ie)
1536 {
1537 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1538 		ie += 4;
1539 	htinfo_parse(ni, (const struct ieee80211_ie_htinfo *) ie);
1540 }
1541 
1542 /*
1543  * Handle 11n/11ac channel switch.
1544  *
1545  * Use the received HT/VHT ie's to identify the right channel to use.
1546  * If we cannot locate it in the channel table then fallback to
1547  * legacy operation.
1548  *
1549  * Note that we use this information to identify the node's
1550  * channel only; the caller is responsible for insuring any
1551  * required channel change is done (e.g. in sta mode when
1552  * parsing the contents of a beacon frame).
1553  */
1554 static int
1555 htinfo_update_chw(struct ieee80211_node *ni, int htflags, int vhtflags)
1556 {
1557 	struct ieee80211com *ic = ni->ni_ic;
1558 	struct ieee80211_channel *c;
1559 	int chanflags;
1560 	int ret = 0;
1561 
1562 	/*
1563 	 * First step - do HT/VHT only channel lookup based on operating mode
1564 	 * flags.  This involves masking out the VHT flags as well.
1565 	 * Otherwise we end up doing the full channel walk each time
1566 	 * we trigger this, which is expensive.
1567 	 */
1568 	chanflags = (ni->ni_chan->ic_flags &~
1569 	    (IEEE80211_CHAN_HT | IEEE80211_CHAN_VHT)) | htflags | vhtflags;
1570 
1571 	if (chanflags == ni->ni_chan->ic_flags)
1572 		goto done;
1573 
1574 	/*
1575 	 * If HT /or/ VHT flags have changed then check both.
1576 	 * We need to start by picking a HT channel anyway.
1577 	 */
1578 
1579 	c = NULL;
1580 	chanflags = (ni->ni_chan->ic_flags &~
1581 	    (IEEE80211_CHAN_HT | IEEE80211_CHAN_VHT)) | htflags;
1582 	/* XXX not right for ht40- */
1583 	c = ieee80211_find_channel(ic, ni->ni_chan->ic_freq, chanflags);
1584 	if (c == NULL && (htflags & IEEE80211_CHAN_HT40)) {
1585 		/*
1586 		 * No HT40 channel entry in our table; fall back
1587 		 * to HT20 operation.  This should not happen.
1588 		 */
1589 		c = findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT20);
1590 #if 0
1591 		IEEE80211_NOTE(ni->ni_vap,
1592 		    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1593 		    "no HT40 channel (freq %u), falling back to HT20",
1594 		    ni->ni_chan->ic_freq);
1595 #endif
1596 		/* XXX stat */
1597 	}
1598 
1599 	/* Nothing found - leave it alone; move onto VHT */
1600 	if (c == NULL)
1601 		c = ni->ni_chan;
1602 
1603 	/*
1604 	 * If it's non-HT, then bail out now.
1605 	 */
1606 	if (! IEEE80211_IS_CHAN_HT(c)) {
1607 		IEEE80211_NOTE(ni->ni_vap,
1608 		    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1609 		    "not HT; skipping VHT check (%u/0x%x)",
1610 		    c->ic_freq, c->ic_flags);
1611 		goto done;
1612 	}
1613 
1614 	/*
1615 	 * Next step - look at the current VHT flags and determine
1616 	 * if we need to upgrade.  Mask out the VHT and HT flags since
1617 	 * the vhtflags field will already have the correct HT
1618 	 * flags to use.
1619 	 */
1620 	if (IEEE80211_CONF_VHT(ic) && ni->ni_vhtcap != 0 && vhtflags != 0) {
1621 		chanflags = (c->ic_flags
1622 		    &~ (IEEE80211_CHAN_HT | IEEE80211_CHAN_VHT))
1623 		    | vhtflags;
1624 		IEEE80211_NOTE(ni->ni_vap,
1625 		    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1626 		    ni,
1627 		    "%s: VHT; chanwidth=0x%02x; vhtflags=0x%08x",
1628 		    __func__, ni->ni_vht_chanwidth, vhtflags);
1629 
1630 		IEEE80211_NOTE(ni->ni_vap,
1631 		    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1632 		    ni,
1633 		    "%s: VHT; trying lookup for %d/0x%08x",
1634 		    __func__, c->ic_freq, chanflags);
1635 		c = ieee80211_find_channel(ic, c->ic_freq, chanflags);
1636 	}
1637 
1638 	/* Finally, if it's changed */
1639 	if (c != NULL && c != ni->ni_chan) {
1640 		IEEE80211_NOTE(ni->ni_vap,
1641 		    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1642 		    "switch station to %s%d channel %u/0x%x",
1643 		    IEEE80211_IS_CHAN_VHT(c) ? "VHT" : "HT",
1644 		    IEEE80211_IS_CHAN_VHT80(c) ? 80 :
1645 		      (IEEE80211_IS_CHAN_HT40(c) ? 40 : 20),
1646 		    c->ic_freq, c->ic_flags);
1647 		ni->ni_chan = c;
1648 		ret = 1;
1649 	}
1650 	/* NB: caller responsible for forcing any channel change */
1651 
1652 done:
1653 	/* update node's (11n) tx channel width */
1654 	ni->ni_chw = IEEE80211_IS_CHAN_HT40(ni->ni_chan)? 40 : 20;
1655 	return (ret);
1656 }
1657 
1658 /*
1659  * Update 11n MIMO PS state according to received htcap.
1660  */
1661 static __inline int
1662 htcap_update_mimo_ps(struct ieee80211_node *ni)
1663 {
1664 	uint16_t oflags = ni->ni_flags;
1665 
1666 	switch (ni->ni_htcap & IEEE80211_HTCAP_SMPS) {
1667 	case IEEE80211_HTCAP_SMPS_DYNAMIC:
1668 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1669 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1670 		break;
1671 	case IEEE80211_HTCAP_SMPS_ENA:
1672 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1673 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1674 		break;
1675 	case IEEE80211_HTCAP_SMPS_OFF:
1676 	default:		/* disable on rx of reserved value */
1677 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1678 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1679 		break;
1680 	}
1681 	return (oflags ^ ni->ni_flags);
1682 }
1683 
1684 /*
1685  * Update short GI state according to received htcap
1686  * and local settings.
1687  */
1688 static __inline void
1689 htcap_update_shortgi(struct ieee80211_node *ni)
1690 {
1691 	struct ieee80211vap *vap = ni->ni_vap;
1692 
1693 	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
1694 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
1695 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20))
1696 		ni->ni_flags |= IEEE80211_NODE_SGI20;
1697 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
1698 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40))
1699 		ni->ni_flags |= IEEE80211_NODE_SGI40;
1700 }
1701 
1702 /*
1703  * Update LDPC state according to received htcap
1704  * and local settings.
1705  */
1706 static __inline void
1707 htcap_update_ldpc(struct ieee80211_node *ni)
1708 {
1709 	struct ieee80211vap *vap = ni->ni_vap;
1710 
1711 	if ((ni->ni_htcap & IEEE80211_HTCAP_LDPC) &&
1712 	    (vap->iv_flags_ht & IEEE80211_FHT_LDPC_TX))
1713 		ni->ni_flags |= IEEE80211_NODE_LDPC;
1714 }
1715 
1716 /*
1717  * Parse and update HT-related state extracted from
1718  * the HT cap and info ie's.
1719  *
1720  * This is called from the STA management path and
1721  * the ieee80211_node_join() path.  It will take into
1722  * account the IEs discovered during scanning and
1723  * adjust things accordingly.
1724  */
1725 void
1726 ieee80211_ht_updateparams(struct ieee80211_node *ni,
1727 	const uint8_t *htcapie, const uint8_t *htinfoie)
1728 {
1729 	struct ieee80211vap *vap = ni->ni_vap;
1730 	const struct ieee80211_ie_htinfo *htinfo;
1731 
1732 	ieee80211_parse_htcap(ni, htcapie);
1733 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1734 		htcap_update_mimo_ps(ni);
1735 	htcap_update_shortgi(ni);
1736 	htcap_update_ldpc(ni);
1737 
1738 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
1739 		htinfoie += 4;
1740 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1741 	htinfo_parse(ni, htinfo);
1742 
1743 	/*
1744 	 * Defer the node channel change; we need to now
1745 	 * update VHT parameters before we do it.
1746 	 */
1747 
1748 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_RIFSMODE_PERM) &&
1749 	    (vap->iv_flags_ht & IEEE80211_FHT_RIFS))
1750 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1751 	else
1752 		ni->ni_flags &= ~IEEE80211_NODE_RIFS;
1753 }
1754 
1755 static uint32_t
1756 ieee80211_vht_get_vhtflags(struct ieee80211_node *ni, uint32_t htflags)
1757 {
1758 	struct ieee80211vap *vap = ni->ni_vap;
1759 	uint32_t vhtflags = 0;
1760 
1761 	vhtflags = 0;
1762 	if (ni->ni_flags & IEEE80211_NODE_VHT && vap->iv_flags_vht & IEEE80211_FVHT_VHT) {
1763 		if ((ni->ni_vht_chanwidth == IEEE80211_VHT_CHANWIDTH_160MHZ) &&
1764 		    /* XXX 2 means "160MHz and 80+80MHz", 1 means "160MHz" */
1765 		    (MS(vap->iv_vhtcaps,
1766 		     IEEE80211_VHTCAP_SUPP_CHAN_WIDTH_MASK) >= 1) &&
1767 		    (vap->iv_flags_vht & IEEE80211_FVHT_USEVHT160)) {
1768 			vhtflags = IEEE80211_CHAN_VHT160;
1769 			/* Mirror the HT40 flags */
1770 			if (htflags == IEEE80211_CHAN_HT40U) {
1771 				vhtflags |= IEEE80211_CHAN_HT40U;
1772 			} else if (htflags == IEEE80211_CHAN_HT40D) {
1773 				vhtflags |= IEEE80211_CHAN_HT40D;
1774 			}
1775 		} else if ((ni->ni_vht_chanwidth == IEEE80211_VHT_CHANWIDTH_80P80MHZ) &&
1776 		    /* XXX 2 means "160MHz and 80+80MHz" */
1777 		    (MS(vap->iv_vhtcaps,
1778 		     IEEE80211_VHTCAP_SUPP_CHAN_WIDTH_MASK) == 2) &&
1779 		    (vap->iv_flags_vht & IEEE80211_FVHT_USEVHT80P80)) {
1780 			vhtflags = IEEE80211_CHAN_VHT80_80;
1781 			/* Mirror the HT40 flags */
1782 			if (htflags == IEEE80211_CHAN_HT40U) {
1783 				vhtflags |= IEEE80211_CHAN_HT40U;
1784 			} else if (htflags == IEEE80211_CHAN_HT40D) {
1785 				vhtflags |= IEEE80211_CHAN_HT40D;
1786 			}
1787 		} else if ((ni->ni_vht_chanwidth == IEEE80211_VHT_CHANWIDTH_80MHZ) &&
1788 		    (vap->iv_flags_vht & IEEE80211_FVHT_USEVHT80)) {
1789 			vhtflags = IEEE80211_CHAN_VHT80;
1790 			/* Mirror the HT40 flags */
1791 			if (htflags == IEEE80211_CHAN_HT40U) {
1792 				vhtflags |= IEEE80211_CHAN_HT40U;
1793 			} else if (htflags == IEEE80211_CHAN_HT40D) {
1794 				vhtflags |= IEEE80211_CHAN_HT40D;
1795 			}
1796 		} else if (ni->ni_vht_chanwidth == IEEE80211_VHT_CHANWIDTH_USE_HT) {
1797 			/* Mirror the HT40 flags */
1798 			/*
1799 			 * XXX TODO: if ht40 is disabled, but vht40 isn't
1800 			 * disabled then this logic will get very, very sad.
1801 			 * It's quite possible the only sane thing to do is
1802 			 * to not have vht40 as an option, and just obey
1803 			 * 'ht40' as that flag.
1804 			 */
1805 			if ((htflags == IEEE80211_CHAN_HT40U) &&
1806 			    (vap->iv_flags_vht & IEEE80211_FVHT_USEVHT40)) {
1807 				vhtflags = IEEE80211_CHAN_VHT40U
1808 				    | IEEE80211_CHAN_HT40U;
1809 			} else if (htflags == IEEE80211_CHAN_HT40D &&
1810 			    (vap->iv_flags_vht & IEEE80211_FVHT_USEVHT40)) {
1811 				vhtflags = IEEE80211_CHAN_VHT40D
1812 				    | IEEE80211_CHAN_HT40D;
1813 			} else if (htflags == IEEE80211_CHAN_HT20) {
1814 				vhtflags = IEEE80211_CHAN_VHT20
1815 				    | IEEE80211_CHAN_HT20;
1816 			}
1817 		} else {
1818 			vhtflags = IEEE80211_CHAN_VHT20;
1819 		}
1820 	}
1821 	return (vhtflags);
1822 }
1823 
1824 /*
1825  * Final part of updating the HT parameters.
1826  *
1827  * This is called from the STA management path and
1828  * the ieee80211_node_join() path.  It will take into
1829  * account the IEs discovered during scanning and
1830  * adjust things accordingly.
1831  *
1832  * This is done after a call to ieee80211_ht_updateparams()
1833  * because it (and the upcoming VHT version of updateparams)
1834  * needs to ensure everything is parsed before htinfo_update_chw()
1835  * is called - which will change the channel config for the
1836  * node for us.
1837  */
1838 int
1839 ieee80211_ht_updateparams_final(struct ieee80211_node *ni,
1840 	const uint8_t *htcapie, const uint8_t *htinfoie)
1841 {
1842 	struct ieee80211vap *vap = ni->ni_vap;
1843 	const struct ieee80211_ie_htinfo *htinfo;
1844 	int htflags, vhtflags;
1845 	int ret = 0;
1846 
1847 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1848 
1849 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1850 	    IEEE80211_CHAN_HT20 : 0;
1851 
1852 	/* NB: honor operating mode constraint */
1853 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_TXWIDTH_2040) &&
1854 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1855 		if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_ABOVE)
1856 			htflags = IEEE80211_CHAN_HT40U;
1857 		else if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_BELOW)
1858 			htflags = IEEE80211_CHAN_HT40D;
1859 	}
1860 
1861 	/*
1862 	 * VHT flags - do much the same; check whether VHT is available
1863 	 * and if so, what our ideal channel use would be based on our
1864 	 * capabilities and the (pre-parsed) VHT info IE.
1865 	 */
1866 	vhtflags = ieee80211_vht_get_vhtflags(ni, htflags);
1867 
1868 	if (htinfo_update_chw(ni, htflags, vhtflags))
1869 		ret = 1;
1870 
1871 	return (ret);
1872 }
1873 
1874 /*
1875  * Parse and update HT-related state extracted from the HT cap ie
1876  * for a station joining an HT BSS.
1877  *
1878  * This is called from the hostap path for each station.
1879  */
1880 void
1881 ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
1882 {
1883 	struct ieee80211vap *vap = ni->ni_vap;
1884 
1885 	ieee80211_parse_htcap(ni, htcapie);
1886 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1887 		htcap_update_mimo_ps(ni);
1888 	htcap_update_shortgi(ni);
1889 	htcap_update_ldpc(ni);
1890 }
1891 
1892 /*
1893  * Called once HT and VHT capabilities are parsed in hostap mode -
1894  * this will adjust the channel configuration of the given node
1895  * based on the configuration and capabilities.
1896  */
1897 void
1898 ieee80211_ht_updatehtcap_final(struct ieee80211_node *ni)
1899 {
1900 	struct ieee80211vap *vap = ni->ni_vap;
1901 	int htflags;
1902 	int vhtflags;
1903 
1904 	/* NB: honor operating mode constraint */
1905 	/* XXX 40 MHz intolerant */
1906 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1907 	    IEEE80211_CHAN_HT20 : 0;
1908 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) &&
1909 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1910 		if (IEEE80211_IS_CHAN_HT40U(vap->iv_bss->ni_chan))
1911 			htflags = IEEE80211_CHAN_HT40U;
1912 		else if (IEEE80211_IS_CHAN_HT40D(vap->iv_bss->ni_chan))
1913 			htflags = IEEE80211_CHAN_HT40D;
1914 	}
1915 	/*
1916 	 * VHT flags - do much the same; check whether VHT is available
1917 	 * and if so, what our ideal channel use would be based on our
1918 	 * capabilities and the (pre-parsed) VHT info IE.
1919 	 */
1920 	vhtflags = ieee80211_vht_get_vhtflags(ni, htflags);
1921 
1922 	(void) htinfo_update_chw(ni, htflags, vhtflags);
1923 }
1924 
1925 /*
1926  * Install received HT rate set by parsing the HT cap ie.
1927  */
1928 int
1929 ieee80211_setup_htrates(struct ieee80211_node *ni, const uint8_t *ie, int flags)
1930 {
1931 	struct ieee80211com *ic = ni->ni_ic;
1932 	struct ieee80211vap *vap = ni->ni_vap;
1933 	const struct ieee80211_ie_htcap *htcap;
1934 	struct ieee80211_htrateset *rs;
1935 	int i, maxequalmcs, maxunequalmcs;
1936 
1937 	maxequalmcs = ic->ic_txstream * 8 - 1;
1938 	maxunequalmcs = 0;
1939 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
1940 		if (ic->ic_txstream >= 2)
1941 			maxunequalmcs = 38;
1942 		if (ic->ic_txstream >= 3)
1943 			maxunequalmcs = 52;
1944 		if (ic->ic_txstream >= 4)
1945 			maxunequalmcs = 76;
1946 	}
1947 
1948 	rs = &ni->ni_htrates;
1949 	memset(rs, 0, sizeof(*rs));
1950 	if (ie != NULL) {
1951 		if (ie[0] == IEEE80211_ELEMID_VENDOR)
1952 			ie += 4;
1953 		htcap = (const struct ieee80211_ie_htcap *) ie;
1954 		for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1955 			if (isclr(htcap->hc_mcsset, i))
1956 				continue;
1957 			if (rs->rs_nrates == IEEE80211_HTRATE_MAXSIZE) {
1958 				IEEE80211_NOTE(vap,
1959 				    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1960 				    "WARNING, HT rate set too large; only "
1961 				    "using %u rates", IEEE80211_HTRATE_MAXSIZE);
1962 				vap->iv_stats.is_rx_rstoobig++;
1963 				break;
1964 			}
1965 			if (i <= 31 && i > maxequalmcs)
1966 				continue;
1967 			if (i == 32 &&
1968 			    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32) == 0)
1969 				continue;
1970 			if (i > 32 && i > maxunequalmcs)
1971 				continue;
1972 			rs->rs_rates[rs->rs_nrates++] = i;
1973 		}
1974 	}
1975 	return ieee80211_fix_rate(ni, (struct ieee80211_rateset *) rs, flags);
1976 }
1977 
1978 /*
1979  * Mark rates in a node's HT rate set as basic according
1980  * to the information in the supplied HT info ie.
1981  */
1982 void
1983 ieee80211_setup_basic_htrates(struct ieee80211_node *ni, const uint8_t *ie)
1984 {
1985 	const struct ieee80211_ie_htinfo *htinfo;
1986 	struct ieee80211_htrateset *rs;
1987 	int i, j;
1988 
1989 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1990 		ie += 4;
1991 	htinfo = (const struct ieee80211_ie_htinfo *) ie;
1992 	rs = &ni->ni_htrates;
1993 	if (rs->rs_nrates == 0) {
1994 		IEEE80211_NOTE(ni->ni_vap,
1995 		    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1996 		    "%s", "WARNING, empty HT rate set");
1997 		return;
1998 	}
1999 	for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
2000 		if (isclr(htinfo->hi_basicmcsset, i))
2001 			continue;
2002 		for (j = 0; j < rs->rs_nrates; j++)
2003 			if ((rs->rs_rates[j] & IEEE80211_RATE_VAL) == i)
2004 				rs->rs_rates[j] |= IEEE80211_RATE_BASIC;
2005 	}
2006 }
2007 
2008 static void
2009 ampdu_tx_setup(struct ieee80211_tx_ampdu *tap)
2010 {
2011 	callout_init(&tap->txa_timer, 1);
2012 	tap->txa_flags |= IEEE80211_AGGR_SETUP;
2013 	tap->txa_lastsample = ticks;
2014 }
2015 
2016 static void
2017 ampdu_tx_stop(struct ieee80211_tx_ampdu *tap)
2018 {
2019 	struct ieee80211_node *ni = tap->txa_ni;
2020 	struct ieee80211com *ic = ni->ni_ic;
2021 
2022 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2023 	    tap->txa_ni,
2024 	    "%s: called",
2025 	    __func__);
2026 
2027 	KASSERT(tap->txa_flags & IEEE80211_AGGR_SETUP,
2028 	    ("txa_flags 0x%x tid %d ac %d", tap->txa_flags, tap->txa_tid,
2029 	    TID_TO_WME_AC(tap->txa_tid)));
2030 
2031 	/*
2032 	 * Stop BA stream if setup so driver has a chance
2033 	 * to reclaim any resources it might have allocated.
2034 	 */
2035 	ic->ic_addba_stop(ni, tap);
2036 	/*
2037 	 * Stop any pending BAR transmit.
2038 	 */
2039 	bar_stop_timer(tap);
2040 
2041 	/*
2042 	 * Reset packet estimate.
2043 	 */
2044 	ieee80211_txampdu_init_pps(tap);
2045 
2046 	/* NB: clearing NAK means we may re-send ADDBA */
2047 	tap->txa_flags &= ~(IEEE80211_AGGR_SETUP | IEEE80211_AGGR_NAK);
2048 }
2049 
2050 /*
2051  * ADDBA response timeout.
2052  *
2053  * If software aggregation and per-TID queue management was done here,
2054  * that queue would be unpaused after the ADDBA timeout occurs.
2055  */
2056 static void
2057 addba_timeout(void *arg)
2058 {
2059 	struct ieee80211_tx_ampdu *tap = arg;
2060 	struct ieee80211_node *ni = tap->txa_ni;
2061 	struct ieee80211com *ic = ni->ni_ic;
2062 
2063 	/* XXX ? */
2064 	tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
2065 	tap->txa_attempts++;
2066 	ic->ic_addba_response_timeout(ni, tap);
2067 }
2068 
2069 static void
2070 addba_start_timeout(struct ieee80211_tx_ampdu *tap)
2071 {
2072 	/* XXX use CALLOUT_PENDING instead? */
2073 	callout_reset(&tap->txa_timer, ieee80211_addba_timeout,
2074 	    addba_timeout, tap);
2075 	tap->txa_flags |= IEEE80211_AGGR_XCHGPEND;
2076 	tap->txa_nextrequest = ticks + ieee80211_addba_timeout;
2077 }
2078 
2079 static void
2080 addba_stop_timeout(struct ieee80211_tx_ampdu *tap)
2081 {
2082 	/* XXX use CALLOUT_PENDING instead? */
2083 	if (tap->txa_flags & IEEE80211_AGGR_XCHGPEND) {
2084 		callout_stop(&tap->txa_timer);
2085 		tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
2086 	}
2087 }
2088 
2089 static void
2090 null_addba_response_timeout(struct ieee80211_node *ni,
2091     struct ieee80211_tx_ampdu *tap)
2092 {
2093 }
2094 
2095 /*
2096  * Default method for requesting A-MPDU tx aggregation.
2097  * We setup the specified state block and start a timer
2098  * to wait for an ADDBA response frame.
2099  */
2100 static int
2101 ieee80211_addba_request(struct ieee80211_node *ni,
2102 	struct ieee80211_tx_ampdu *tap,
2103 	int dialogtoken, int baparamset, int batimeout)
2104 {
2105 	int bufsiz;
2106 
2107 	/* XXX locking */
2108 	tap->txa_token = dialogtoken;
2109 	tap->txa_flags |= IEEE80211_AGGR_IMMEDIATE;
2110 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
2111 	tap->txa_wnd = (bufsiz == 0) ?
2112 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
2113 	addba_start_timeout(tap);
2114 	return 1;
2115 }
2116 
2117 /*
2118  * Called by drivers that wish to request an ADDBA session be
2119  * setup.  This brings it up and starts the request timer.
2120  */
2121 int
2122 ieee80211_ampdu_tx_request_ext(struct ieee80211_node *ni, int tid)
2123 {
2124 	struct ieee80211_tx_ampdu *tap;
2125 
2126 	if (tid < 0 || tid > 15)
2127 		return (0);
2128 	tap = &ni->ni_tx_ampdu[tid];
2129 
2130 	/* XXX locking */
2131 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
2132 		/* do deferred setup of state */
2133 		ampdu_tx_setup(tap);
2134 	}
2135 	/* XXX hack for not doing proper locking */
2136 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
2137 	addba_start_timeout(tap);
2138 	return (1);
2139 }
2140 
2141 /*
2142  * Called by drivers that have marked a session as active.
2143  */
2144 int
2145 ieee80211_ampdu_tx_request_active_ext(struct ieee80211_node *ni, int tid,
2146     int status)
2147 {
2148 	struct ieee80211_tx_ampdu *tap;
2149 
2150 	if (tid < 0 || tid > 15)
2151 		return (0);
2152 	tap = &ni->ni_tx_ampdu[tid];
2153 
2154 	/* XXX locking */
2155 	addba_stop_timeout(tap);
2156 	if (status == 1) {
2157 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
2158 		tap->txa_attempts = 0;
2159 	} else {
2160 		/* mark tid so we don't try again */
2161 		tap->txa_flags |= IEEE80211_AGGR_NAK;
2162 	}
2163 	return (1);
2164 }
2165 
2166 /*
2167  * Default method for processing an A-MPDU tx aggregation
2168  * response.  We shutdown any pending timer and update the
2169  * state block according to the reply.
2170  */
2171 static int
2172 ieee80211_addba_response(struct ieee80211_node *ni,
2173 	struct ieee80211_tx_ampdu *tap,
2174 	int status, int baparamset, int batimeout)
2175 {
2176 	int bufsiz, tid;
2177 
2178 	/* XXX locking */
2179 	addba_stop_timeout(tap);
2180 	if (status == IEEE80211_STATUS_SUCCESS) {
2181 		bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
2182 		/* XXX override our request? */
2183 		tap->txa_wnd = (bufsiz == 0) ?
2184 		    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
2185 		/* XXX AC/TID */
2186 		tid = MS(baparamset, IEEE80211_BAPS_TID);
2187 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
2188 		tap->txa_attempts = 0;
2189 	} else {
2190 		/* mark tid so we don't try again */
2191 		tap->txa_flags |= IEEE80211_AGGR_NAK;
2192 	}
2193 	return 1;
2194 }
2195 
2196 /*
2197  * Default method for stopping A-MPDU tx aggregation.
2198  * Any timer is cleared and we drain any pending frames.
2199  */
2200 static void
2201 ieee80211_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
2202 {
2203 	/* XXX locking */
2204 	addba_stop_timeout(tap);
2205 	if (tap->txa_flags & IEEE80211_AGGR_RUNNING) {
2206 		/* XXX clear aggregation queue */
2207 		tap->txa_flags &= ~IEEE80211_AGGR_RUNNING;
2208 	}
2209 	tap->txa_attempts = 0;
2210 }
2211 
2212 /*
2213  * Process a received action frame using the default aggregation
2214  * policy.  We intercept ADDBA-related frames and use them to
2215  * update our aggregation state.  All other frames are passed up
2216  * for processing by ieee80211_recv_action.
2217  */
2218 static int
2219 ht_recv_action_ba_addba_request(struct ieee80211_node *ni,
2220 	const struct ieee80211_frame *wh,
2221 	const uint8_t *frm, const uint8_t *efrm)
2222 {
2223 	struct ieee80211com *ic = ni->ni_ic;
2224 	struct ieee80211vap *vap = ni->ni_vap;
2225 	struct ieee80211_rx_ampdu *rap;
2226 	uint8_t dialogtoken;
2227 	uint16_t baparamset, batimeout, baseqctl;
2228 	uint16_t args[5];
2229 	int tid;
2230 
2231 	dialogtoken = frm[2];
2232 	baparamset = le16dec(frm+3);
2233 	batimeout = le16dec(frm+5);
2234 	baseqctl = le16dec(frm+7);
2235 
2236 	tid = MS(baparamset, IEEE80211_BAPS_TID);
2237 
2238 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2239 	    "recv ADDBA request: dialogtoken %u baparamset 0x%x "
2240 	    "(tid %d bufsiz %d) batimeout %d baseqctl %d:%d",
2241 	    dialogtoken, baparamset,
2242 	    tid, MS(baparamset, IEEE80211_BAPS_BUFSIZ),
2243 	    batimeout,
2244 	    MS(baseqctl, IEEE80211_BASEQ_START),
2245 	    MS(baseqctl, IEEE80211_BASEQ_FRAG));
2246 
2247 	rap = &ni->ni_rx_ampdu[tid];
2248 
2249 	/* Send ADDBA response */
2250 	args[0] = dialogtoken;
2251 	/*
2252 	 * NB: We ack only if the sta associated with HT and
2253 	 * the ap is configured to do AMPDU rx (the latter
2254 	 * violates the 11n spec and is mostly for testing).
2255 	 */
2256 	if ((ni->ni_flags & IEEE80211_NODE_AMPDU_RX) &&
2257 	    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_RX)) {
2258 		/* XXX handle ampdu_rx_start failure */
2259 		ic->ic_ampdu_rx_start(ni, rap,
2260 		    baparamset, batimeout, baseqctl);
2261 
2262 		args[1] = IEEE80211_STATUS_SUCCESS;
2263 	} else {
2264 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2265 		    ni, "reject ADDBA request: %s",
2266 		    ni->ni_flags & IEEE80211_NODE_AMPDU_RX ?
2267 		       "administratively disabled" :
2268 		       "not negotiated for station");
2269 		vap->iv_stats.is_addba_reject++;
2270 		args[1] = IEEE80211_STATUS_UNSPECIFIED;
2271 	}
2272 	/* XXX honor rap flags? */
2273 	args[2] = IEEE80211_BAPS_POLICY_IMMEDIATE
2274 		| SM(tid, IEEE80211_BAPS_TID)
2275 		| SM(rap->rxa_wnd, IEEE80211_BAPS_BUFSIZ)
2276 		;
2277 	args[3] = 0;
2278 	args[4] = 0;
2279 	ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2280 		IEEE80211_ACTION_BA_ADDBA_RESPONSE, args);
2281 	return 0;
2282 }
2283 
2284 static int
2285 ht_recv_action_ba_addba_response(struct ieee80211_node *ni,
2286 	const struct ieee80211_frame *wh,
2287 	const uint8_t *frm, const uint8_t *efrm)
2288 {
2289 	struct ieee80211com *ic = ni->ni_ic;
2290 	struct ieee80211vap *vap = ni->ni_vap;
2291 	struct ieee80211_tx_ampdu *tap;
2292 	uint8_t dialogtoken, policy;
2293 	uint16_t baparamset, batimeout, code;
2294 	int tid, bufsiz;
2295 
2296 	dialogtoken = frm[2];
2297 	code = le16dec(frm+3);
2298 	baparamset = le16dec(frm+5);
2299 	tid = MS(baparamset, IEEE80211_BAPS_TID);
2300 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
2301 	policy = MS(baparamset, IEEE80211_BAPS_POLICY);
2302 	batimeout = le16dec(frm+7);
2303 
2304 	tap = &ni->ni_tx_ampdu[tid];
2305 	if ((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
2306 		IEEE80211_DISCARD_MAC(vap,
2307 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2308 		    ni->ni_macaddr, "ADDBA response",
2309 		    "no pending ADDBA, tid %d dialogtoken %u "
2310 		    "code %d", tid, dialogtoken, code);
2311 		vap->iv_stats.is_addba_norequest++;
2312 		return 0;
2313 	}
2314 	if (dialogtoken != tap->txa_token) {
2315 		IEEE80211_DISCARD_MAC(vap,
2316 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2317 		    ni->ni_macaddr, "ADDBA response",
2318 		    "dialogtoken mismatch: waiting for %d, "
2319 		    "received %d, tid %d code %d",
2320 		    tap->txa_token, dialogtoken, tid, code);
2321 		vap->iv_stats.is_addba_badtoken++;
2322 		return 0;
2323 	}
2324 	/* NB: assumes IEEE80211_AGGR_IMMEDIATE is 1 */
2325 	if (policy != (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE)) {
2326 		IEEE80211_DISCARD_MAC(vap,
2327 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2328 		    ni->ni_macaddr, "ADDBA response",
2329 		    "policy mismatch: expecting %s, "
2330 		    "received %s, tid %d code %d",
2331 		    tap->txa_flags & IEEE80211_AGGR_IMMEDIATE,
2332 		    policy, tid, code);
2333 		vap->iv_stats.is_addba_badpolicy++;
2334 		return 0;
2335 	}
2336 #if 0
2337 	/* XXX we take MIN in ieee80211_addba_response */
2338 	if (bufsiz > IEEE80211_AGGR_BAWMAX) {
2339 		IEEE80211_DISCARD_MAC(vap,
2340 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2341 		    ni->ni_macaddr, "ADDBA response",
2342 		    "BA window too large: max %d, "
2343 		    "received %d, tid %d code %d",
2344 		    bufsiz, IEEE80211_AGGR_BAWMAX, tid, code);
2345 		vap->iv_stats.is_addba_badbawinsize++;
2346 		return 0;
2347 	}
2348 #endif
2349 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2350 	    "recv ADDBA response: dialogtoken %u code %d "
2351 	    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d",
2352 	    dialogtoken, code, baparamset, tid, bufsiz,
2353 	    batimeout);
2354 	ic->ic_addba_response(ni, tap, code, baparamset, batimeout);
2355 	return 0;
2356 }
2357 
2358 static int
2359 ht_recv_action_ba_delba(struct ieee80211_node *ni,
2360 	const struct ieee80211_frame *wh,
2361 	const uint8_t *frm, const uint8_t *efrm)
2362 {
2363 	struct ieee80211com *ic = ni->ni_ic;
2364 	struct ieee80211_rx_ampdu *rap;
2365 	struct ieee80211_tx_ampdu *tap;
2366 	uint16_t baparamset, code;
2367 	int tid;
2368 
2369 	baparamset = le16dec(frm+2);
2370 	code = le16dec(frm+4);
2371 
2372 	tid = MS(baparamset, IEEE80211_DELBAPS_TID);
2373 
2374 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2375 	    "recv DELBA: baparamset 0x%x (tid %d initiator %d) "
2376 	    "code %d", baparamset, tid,
2377 	    MS(baparamset, IEEE80211_DELBAPS_INIT), code);
2378 
2379 	if ((baparamset & IEEE80211_DELBAPS_INIT) == 0) {
2380 		tap = &ni->ni_tx_ampdu[tid];
2381 		ic->ic_addba_stop(ni, tap);
2382 	} else {
2383 		rap = &ni->ni_rx_ampdu[tid];
2384 		ic->ic_ampdu_rx_stop(ni, rap);
2385 	}
2386 	return 0;
2387 }
2388 
2389 static int
2390 ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
2391 	const struct ieee80211_frame *wh,
2392 	const uint8_t *frm, const uint8_t *efrm)
2393 {
2394 	int chw;
2395 
2396 	chw = (frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040) ? 40 : 20;
2397 
2398 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2399 	    "%s: HT txchwidth, width %d%s",
2400 	    __func__, chw, ni->ni_chw != chw ? "*" : "");
2401 	if (chw != ni->ni_chw) {
2402 		/* XXX does this need to change the ht40 station count? */
2403 		ni->ni_chw = chw;
2404 		/* XXX notify on change */
2405 	}
2406 	return 0;
2407 }
2408 
2409 static int
2410 ht_recv_action_ht_mimopwrsave(struct ieee80211_node *ni,
2411 	const struct ieee80211_frame *wh,
2412 	const uint8_t *frm, const uint8_t *efrm)
2413 {
2414 	const struct ieee80211_action_ht_mimopowersave *mps =
2415 	    (const struct ieee80211_action_ht_mimopowersave *) frm;
2416 
2417 	/* XXX check iv_htcaps */
2418 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_ENA)
2419 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
2420 	else
2421 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
2422 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_MODE)
2423 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
2424 	else
2425 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
2426 	/* XXX notify on change */
2427 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2428 	    "%s: HT MIMO PS (%s%s)", __func__,
2429 	    (ni->ni_flags & IEEE80211_NODE_MIMO_PS) ?  "on" : "off",
2430 	    (ni->ni_flags & IEEE80211_NODE_MIMO_RTS) ?  "+rts" : ""
2431 	);
2432 	return 0;
2433 }
2434 
2435 /*
2436  * Transmit processing.
2437  */
2438 
2439 /*
2440  * Check if A-MPDU should be requested/enabled for a stream.
2441  * We require a traffic rate above a per-AC threshold and we
2442  * also handle backoff from previous failed attempts.
2443  *
2444  * Drivers may override this method to bring in information
2445  * such as link state conditions in making the decision.
2446  */
2447 static int
2448 ieee80211_ampdu_enable(struct ieee80211_node *ni,
2449 	struct ieee80211_tx_ampdu *tap)
2450 {
2451 	struct ieee80211vap *vap = ni->ni_vap;
2452 
2453 	if (tap->txa_avgpps <
2454 	    vap->iv_ampdu_mintraffic[TID_TO_WME_AC(tap->txa_tid)])
2455 		return 0;
2456 	/* XXX check rssi? */
2457 	if (tap->txa_attempts >= ieee80211_addba_maxtries &&
2458 	    ieee80211_time_after(ticks, tap->txa_nextrequest)) {
2459 		/*
2460 		 * Don't retry too often; txa_nextrequest is set
2461 		 * to the minimum interval we'll retry after
2462 		 * ieee80211_addba_maxtries failed attempts are made.
2463 		 */
2464 		return 0;
2465 	}
2466 	IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
2467 	    "enable AMPDU on tid %d (%s), avgpps %d pkts %d attempt %d",
2468 	    tap->txa_tid, ieee80211_wme_acnames[TID_TO_WME_AC(tap->txa_tid)],
2469 	    tap->txa_avgpps, tap->txa_pkts, tap->txa_attempts);
2470 	return 1;
2471 }
2472 
2473 /*
2474  * Request A-MPDU tx aggregation.  Setup local state and
2475  * issue an ADDBA request.  BA use will only happen after
2476  * the other end replies with ADDBA response.
2477  */
2478 int
2479 ieee80211_ampdu_request(struct ieee80211_node *ni,
2480 	struct ieee80211_tx_ampdu *tap)
2481 {
2482 	struct ieee80211com *ic = ni->ni_ic;
2483 	uint16_t args[5];
2484 	int tid, dialogtoken;
2485 	static int tokens = 0;	/* XXX */
2486 
2487 	/* XXX locking */
2488 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
2489 		/* do deferred setup of state */
2490 		ampdu_tx_setup(tap);
2491 	}
2492 	/* XXX hack for not doing proper locking */
2493 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
2494 
2495 	dialogtoken = (tokens+1) % 63;		/* XXX */
2496 	tid = tap->txa_tid;
2497 
2498 	/*
2499 	 * XXX TODO: This is racy with any other parallel TX going on. :(
2500 	 */
2501 	tap->txa_start = ni->ni_txseqs[tid];
2502 
2503 	args[0] = dialogtoken;
2504 	args[1] = 0;	/* NB: status code not used */
2505 	args[2]	= IEEE80211_BAPS_POLICY_IMMEDIATE
2506 		| SM(tid, IEEE80211_BAPS_TID)
2507 		| SM(IEEE80211_AGGR_BAWMAX, IEEE80211_BAPS_BUFSIZ)
2508 		;
2509 	args[3] = 0;	/* batimeout */
2510 	/* NB: do first so there's no race against reply */
2511 	if (!ic->ic_addba_request(ni, tap, dialogtoken, args[2], args[3])) {
2512 		/* unable to setup state, don't make request */
2513 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2514 		    ni, "%s: could not setup BA stream for TID %d AC %d",
2515 		    __func__, tap->txa_tid, TID_TO_WME_AC(tap->txa_tid));
2516 		/* defer next try so we don't slam the driver with requests */
2517 		tap->txa_attempts = ieee80211_addba_maxtries;
2518 		/* NB: check in case driver wants to override */
2519 		if (tap->txa_nextrequest <= ticks)
2520 			tap->txa_nextrequest = ticks + ieee80211_addba_backoff;
2521 		return 0;
2522 	}
2523 	tokens = dialogtoken;			/* allocate token */
2524 	/* NB: after calling ic_addba_request so driver can set txa_start */
2525 	args[4] = SM(tap->txa_start, IEEE80211_BASEQ_START)
2526 		| SM(0, IEEE80211_BASEQ_FRAG)
2527 		;
2528 	return ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2529 		IEEE80211_ACTION_BA_ADDBA_REQUEST, args);
2530 }
2531 
2532 /*
2533  * Terminate an AMPDU tx stream.  State is reclaimed
2534  * and the peer notified with a DelBA Action frame.
2535  */
2536 void
2537 ieee80211_ampdu_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
2538 	int reason)
2539 {
2540 	struct ieee80211com *ic = ni->ni_ic;
2541 	struct ieee80211vap *vap = ni->ni_vap;
2542 	uint16_t args[4];
2543 
2544 	/* XXX locking */
2545 	tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2546 	if (IEEE80211_AMPDU_RUNNING(tap)) {
2547 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2548 		    ni, "%s: stop BA stream for TID %d (reason: %d (%s))",
2549 		    __func__, tap->txa_tid, reason,
2550 		    ieee80211_reason_to_string(reason));
2551 		vap->iv_stats.is_ampdu_stop++;
2552 
2553 		ic->ic_addba_stop(ni, tap);
2554 		args[0] = tap->txa_tid;
2555 		args[1] = IEEE80211_DELBAPS_INIT;
2556 		args[2] = reason;			/* XXX reason code */
2557 		ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2558 			IEEE80211_ACTION_BA_DELBA, args);
2559 	} else {
2560 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2561 		    ni, "%s: BA stream for TID %d not running "
2562 		    "(reason: %d (%s))", __func__, tap->txa_tid, reason,
2563 		    ieee80211_reason_to_string(reason));
2564 		vap->iv_stats.is_ampdu_stop_failed++;
2565 	}
2566 }
2567 
2568 /* XXX */
2569 static void bar_start_timer(struct ieee80211_tx_ampdu *tap);
2570 
2571 static void
2572 bar_timeout(void *arg)
2573 {
2574 	struct ieee80211_tx_ampdu *tap = arg;
2575 	struct ieee80211_node *ni = tap->txa_ni;
2576 
2577 	KASSERT((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0,
2578 	    ("bar/addba collision, flags 0x%x", tap->txa_flags));
2579 
2580 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2581 	    ni, "%s: tid %u flags 0x%x attempts %d", __func__,
2582 	    tap->txa_tid, tap->txa_flags, tap->txa_attempts);
2583 
2584 	/* guard against race with bar_tx_complete */
2585 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2586 		return;
2587 	/* XXX ? */
2588 	if (tap->txa_attempts >= ieee80211_bar_maxtries) {
2589 		struct ieee80211com *ic = ni->ni_ic;
2590 
2591 		ni->ni_vap->iv_stats.is_ampdu_bar_tx_fail++;
2592 		/*
2593 		 * If (at least) the last BAR TX timeout was due to
2594 		 * an ieee80211_send_bar() failures, then we need
2595 		 * to make sure we notify the driver that a BAR
2596 		 * TX did occur and fail.  This gives the driver
2597 		 * a chance to undo any queue pause that may
2598 		 * have occurred.
2599 		 */
2600 		ic->ic_bar_response(ni, tap, 1);
2601 		ieee80211_ampdu_stop(ni, tap, IEEE80211_REASON_TIMEOUT);
2602 	} else {
2603 		ni->ni_vap->iv_stats.is_ampdu_bar_tx_retry++;
2604 		if (ieee80211_send_bar(ni, tap, tap->txa_seqpending) != 0) {
2605 			IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2606 			    ni, "%s: failed to TX, starting timer\n",
2607 			    __func__);
2608 			/*
2609 			 * If ieee80211_send_bar() fails here, the
2610 			 * timer may have stopped and/or the pending
2611 			 * flag may be clear.  Because of this,
2612 			 * fake the BARPEND and reset the timer.
2613 			 * A retransmission attempt will then occur
2614 			 * during the next timeout.
2615 			 */
2616 			/* XXX locking */
2617 			tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2618 			bar_start_timer(tap);
2619 		}
2620 	}
2621 }
2622 
2623 static void
2624 bar_start_timer(struct ieee80211_tx_ampdu *tap)
2625 {
2626 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2627 	    tap->txa_ni,
2628 	    "%s: called",
2629 	    __func__);
2630 	callout_reset(&tap->txa_timer, ieee80211_bar_timeout, bar_timeout, tap);
2631 }
2632 
2633 static void
2634 bar_stop_timer(struct ieee80211_tx_ampdu *tap)
2635 {
2636 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2637 	    tap->txa_ni,
2638 	    "%s: called",
2639 	    __func__);
2640 	callout_stop(&tap->txa_timer);
2641 }
2642 
2643 static void
2644 bar_tx_complete(struct ieee80211_node *ni, void *arg, int status)
2645 {
2646 	struct ieee80211_tx_ampdu *tap = arg;
2647 
2648 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2649 	    ni, "%s: tid %u flags 0x%x pending %d status %d",
2650 	    __func__, tap->txa_tid, tap->txa_flags,
2651 	    callout_pending(&tap->txa_timer), status);
2652 
2653 	ni->ni_vap->iv_stats.is_ampdu_bar_tx++;
2654 	/* XXX locking */
2655 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) &&
2656 	    callout_pending(&tap->txa_timer)) {
2657 		struct ieee80211com *ic = ni->ni_ic;
2658 
2659 		if (status == 0)		/* ACK'd */
2660 			bar_stop_timer(tap);
2661 		ic->ic_bar_response(ni, tap, status);
2662 		/* NB: just let timer expire so we pace requests */
2663 	}
2664 }
2665 
2666 static void
2667 ieee80211_bar_response(struct ieee80211_node *ni,
2668 	struct ieee80211_tx_ampdu *tap, int status)
2669 {
2670 
2671 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2672 	    tap->txa_ni,
2673 	    "%s: called",
2674 	    __func__);
2675 	if (status == 0) {		/* got ACK */
2676 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2677 		    ni, "BAR moves BA win <%u:%u> (%u frames) txseq %u tid %u",
2678 		    tap->txa_start,
2679 		    IEEE80211_SEQ_ADD(tap->txa_start, tap->txa_wnd-1),
2680 		    tap->txa_qframes, tap->txa_seqpending,
2681 		    tap->txa_tid);
2682 
2683 		/* NB: timer already stopped in bar_tx_complete */
2684 		tap->txa_start = tap->txa_seqpending;
2685 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2686 	}
2687 }
2688 
2689 /*
2690  * Transmit a BAR frame to the specified node.  The
2691  * BAR contents are drawn from the supplied aggregation
2692  * state associated with the node.
2693  *
2694  * NB: we only handle immediate ACK w/ compressed bitmap.
2695  */
2696 int
2697 ieee80211_send_bar(struct ieee80211_node *ni,
2698 	struct ieee80211_tx_ampdu *tap, ieee80211_seq seq)
2699 {
2700 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2701 	struct ieee80211vap *vap = ni->ni_vap;
2702 	struct ieee80211com *ic = ni->ni_ic;
2703 	struct ieee80211_frame_bar *bar;
2704 	struct mbuf *m;
2705 	uint16_t barctl, barseqctl;
2706 	uint8_t *frm;
2707 	int tid, ret;
2708 
2709 
2710 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2711 	    tap->txa_ni,
2712 	    "%s: called",
2713 	    __func__);
2714 
2715 	if ((tap->txa_flags & IEEE80211_AGGR_RUNNING) == 0) {
2716 		/* no ADDBA response, should not happen */
2717 		/* XXX stat+msg */
2718 		return EINVAL;
2719 	}
2720 	/* XXX locking */
2721 	bar_stop_timer(tap);
2722 
2723 	ieee80211_ref_node(ni);
2724 
2725 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom, sizeof(*bar));
2726 	if (m == NULL)
2727 		senderr(ENOMEM, is_tx_nobuf);
2728 
2729 	if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
2730 		m_freem(m);
2731 		senderr(ENOMEM, is_tx_nobuf);	/* XXX */
2732 		/* NOTREACHED */
2733 	}
2734 
2735 	bar = mtod(m, struct ieee80211_frame_bar *);
2736 	bar->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2737 		IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_BAR;
2738 	bar->i_fc[1] = 0;
2739 	IEEE80211_ADDR_COPY(bar->i_ra, ni->ni_macaddr);
2740 	IEEE80211_ADDR_COPY(bar->i_ta, vap->iv_myaddr);
2741 
2742 	tid = tap->txa_tid;
2743 	barctl 	= (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE ?
2744 			0 : IEEE80211_BAR_NOACK)
2745 		| IEEE80211_BAR_COMP
2746 		| SM(tid, IEEE80211_BAR_TID)
2747 		;
2748 	barseqctl = SM(seq, IEEE80211_BAR_SEQ_START);
2749 	/* NB: known to have proper alignment */
2750 	bar->i_ctl = htole16(barctl);
2751 	bar->i_seq = htole16(barseqctl);
2752 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_bar);
2753 
2754 	M_WME_SETAC(m, WME_AC_VO);
2755 
2756 	IEEE80211_NODE_STAT(ni, tx_mgmt);	/* XXX tx_ctl? */
2757 
2758 	/* XXX locking */
2759 	/* init/bump attempts counter */
2760 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2761 		tap->txa_attempts = 1;
2762 	else
2763 		tap->txa_attempts++;
2764 	tap->txa_seqpending = seq;
2765 	tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2766 
2767 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2768 	    ni, "send BAR: tid %u ctl 0x%x start %u (attempt %d)",
2769 	    tid, barctl, seq, tap->txa_attempts);
2770 
2771 	/*
2772 	 * ic_raw_xmit will free the node reference
2773 	 * regardless of queue/TX success or failure.
2774 	 */
2775 	IEEE80211_TX_LOCK(ic);
2776 	ret = ieee80211_raw_output(vap, ni, m, NULL);
2777 	IEEE80211_TX_UNLOCK(ic);
2778 	if (ret != 0) {
2779 		IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2780 		    ni, "send BAR: failed: (ret = %d)\n",
2781 		    ret);
2782 		/* xmit failed, clear state flag */
2783 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2784 		vap->iv_stats.is_ampdu_bar_tx_fail++;
2785 		return ret;
2786 	}
2787 	/* XXX hack against tx complete happening before timer is started */
2788 	if (tap->txa_flags & IEEE80211_AGGR_BARPEND)
2789 		bar_start_timer(tap);
2790 	return 0;
2791 bad:
2792 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2793 	    tap->txa_ni,
2794 	    "%s: bad! ret=%d",
2795 	    __func__, ret);
2796 	vap->iv_stats.is_ampdu_bar_tx_fail++;
2797 	ieee80211_free_node(ni);
2798 	return ret;
2799 #undef senderr
2800 }
2801 
2802 static int
2803 ht_action_output(struct ieee80211_node *ni, struct mbuf *m)
2804 {
2805 	struct ieee80211_bpf_params params;
2806 
2807 	memset(&params, 0, sizeof(params));
2808 	params.ibp_pri = WME_AC_VO;
2809 	params.ibp_rate0 = ni->ni_txparms->mgmtrate;
2810 	/* NB: we know all frames are unicast */
2811 	params.ibp_try0 = ni->ni_txparms->maxretry;
2812 	params.ibp_power = ni->ni_txpower;
2813 	return ieee80211_mgmt_output(ni, m, IEEE80211_FC0_SUBTYPE_ACTION,
2814 	     &params);
2815 }
2816 
2817 #define	ADDSHORT(frm, v) do {			\
2818 	frm[0] = (v) & 0xff;			\
2819 	frm[1] = (v) >> 8;			\
2820 	frm += 2;				\
2821 } while (0)
2822 
2823 /*
2824  * Send an action management frame.  The arguments are stuff
2825  * into a frame without inspection; the caller is assumed to
2826  * prepare them carefully (e.g. based on the aggregation state).
2827  */
2828 static int
2829 ht_send_action_ba_addba(struct ieee80211_node *ni,
2830 	int category, int action, void *arg0)
2831 {
2832 	struct ieee80211vap *vap = ni->ni_vap;
2833 	struct ieee80211com *ic = ni->ni_ic;
2834 	uint16_t *args = arg0;
2835 	struct mbuf *m;
2836 	uint8_t *frm;
2837 
2838 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2839 	    "send ADDBA %s: dialogtoken %d status %d "
2840 	    "baparamset 0x%x (tid %d) batimeout 0x%x baseqctl 0x%x",
2841 	    (action == IEEE80211_ACTION_BA_ADDBA_REQUEST) ?
2842 		"request" : "response",
2843 	    args[0], args[1], args[2], MS(args[2], IEEE80211_BAPS_TID),
2844 	    args[3], args[4]);
2845 
2846 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2847 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2848 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2849 	ieee80211_ref_node(ni);
2850 
2851 	m = ieee80211_getmgtframe(&frm,
2852 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2853 	    sizeof(uint16_t)	/* action+category */
2854 	    /* XXX may action payload */
2855 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2856 	);
2857 	if (m != NULL) {
2858 		*frm++ = category;
2859 		*frm++ = action;
2860 		*frm++ = args[0];		/* dialog token */
2861 		if (action == IEEE80211_ACTION_BA_ADDBA_RESPONSE)
2862 			ADDSHORT(frm, args[1]);	/* status code */
2863 		ADDSHORT(frm, args[2]);		/* baparamset */
2864 		ADDSHORT(frm, args[3]);		/* batimeout */
2865 		if (action == IEEE80211_ACTION_BA_ADDBA_REQUEST)
2866 			ADDSHORT(frm, args[4]);	/* baseqctl */
2867 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2868 		return ht_action_output(ni, m);
2869 	} else {
2870 		vap->iv_stats.is_tx_nobuf++;
2871 		ieee80211_free_node(ni);
2872 		return ENOMEM;
2873 	}
2874 }
2875 
2876 static int
2877 ht_send_action_ba_delba(struct ieee80211_node *ni,
2878 	int category, int action, void *arg0)
2879 {
2880 	struct ieee80211vap *vap = ni->ni_vap;
2881 	struct ieee80211com *ic = ni->ni_ic;
2882 	uint16_t *args = arg0;
2883 	struct mbuf *m;
2884 	uint16_t baparamset;
2885 	uint8_t *frm;
2886 
2887 	baparamset = SM(args[0], IEEE80211_DELBAPS_TID)
2888 		   | args[1]
2889 		   ;
2890 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2891 	    "send DELBA action: tid %d, initiator %d reason %d (%s)",
2892 	    args[0], args[1], args[2], ieee80211_reason_to_string(args[2]));
2893 
2894 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2895 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2896 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2897 	ieee80211_ref_node(ni);
2898 
2899 	m = ieee80211_getmgtframe(&frm,
2900 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2901 	    sizeof(uint16_t)	/* action+category */
2902 	    /* XXX may action payload */
2903 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2904 	);
2905 	if (m != NULL) {
2906 		*frm++ = category;
2907 		*frm++ = action;
2908 		ADDSHORT(frm, baparamset);
2909 		ADDSHORT(frm, args[2]);		/* reason code */
2910 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2911 		return ht_action_output(ni, m);
2912 	} else {
2913 		vap->iv_stats.is_tx_nobuf++;
2914 		ieee80211_free_node(ni);
2915 		return ENOMEM;
2916 	}
2917 }
2918 
2919 static int
2920 ht_send_action_ht_txchwidth(struct ieee80211_node *ni,
2921 	int category, int action, void *arg0)
2922 {
2923 	struct ieee80211vap *vap = ni->ni_vap;
2924 	struct ieee80211com *ic = ni->ni_ic;
2925 	struct mbuf *m;
2926 	uint8_t *frm;
2927 
2928 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2929 	    "send HT txchwidth: width %d",
2930 	    IEEE80211_IS_CHAN_HT40(ni->ni_chan) ? 40 : 20);
2931 
2932 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2933 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2934 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2935 	ieee80211_ref_node(ni);
2936 
2937 	m = ieee80211_getmgtframe(&frm,
2938 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2939 	    sizeof(uint16_t)	/* action+category */
2940 	    /* XXX may action payload */
2941 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2942 	);
2943 	if (m != NULL) {
2944 		*frm++ = category;
2945 		*frm++ = action;
2946 		*frm++ = IEEE80211_IS_CHAN_HT40(ni->ni_chan) ?
2947 			IEEE80211_A_HT_TXCHWIDTH_2040 :
2948 			IEEE80211_A_HT_TXCHWIDTH_20;
2949 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2950 		return ht_action_output(ni, m);
2951 	} else {
2952 		vap->iv_stats.is_tx_nobuf++;
2953 		ieee80211_free_node(ni);
2954 		return ENOMEM;
2955 	}
2956 }
2957 #undef ADDSHORT
2958 
2959 /*
2960  * Construct the MCS bit mask for inclusion in an HT capabilities
2961  * information element.
2962  */
2963 static void
2964 ieee80211_set_mcsset(struct ieee80211com *ic, uint8_t *frm)
2965 {
2966 	int i;
2967 	uint8_t txparams;
2968 
2969 	KASSERT((ic->ic_rxstream > 0 && ic->ic_rxstream <= 4),
2970 	    ("ic_rxstream %d out of range", ic->ic_rxstream));
2971 	KASSERT((ic->ic_txstream > 0 && ic->ic_txstream <= 4),
2972 	    ("ic_txstream %d out of range", ic->ic_txstream));
2973 
2974 	for (i = 0; i < ic->ic_rxstream * 8; i++)
2975 		setbit(frm, i);
2976 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
2977 	    (ic->ic_htcaps & IEEE80211_HTC_RXMCS32))
2978 		setbit(frm, 32);
2979 	if (ic->ic_htcaps & IEEE80211_HTC_RXUNEQUAL) {
2980 		if (ic->ic_rxstream >= 2) {
2981 			for (i = 33; i <= 38; i++)
2982 				setbit(frm, i);
2983 		}
2984 		if (ic->ic_rxstream >= 3) {
2985 			for (i = 39; i <= 52; i++)
2986 				setbit(frm, i);
2987 		}
2988 		if (ic->ic_txstream >= 4) {
2989 			for (i = 53; i <= 76; i++)
2990 				setbit(frm, i);
2991 		}
2992 	}
2993 
2994 	if (ic->ic_rxstream != ic->ic_txstream) {
2995 		txparams = 0x1;			/* TX MCS set defined */
2996 		txparams |= 0x2;		/* TX RX MCS not equal */
2997 		txparams |= (ic->ic_txstream - 1) << 2;	/* num TX streams */
2998 		if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL)
2999 			txparams |= 0x16;	/* TX unequal modulation sup */
3000 	} else
3001 		txparams = 0;
3002 	frm[12] = txparams;
3003 }
3004 
3005 /*
3006  * Add body of an HTCAP information element.
3007  */
3008 static uint8_t *
3009 ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
3010 {
3011 #define	ADDSHORT(frm, v) do {			\
3012 	frm[0] = (v) & 0xff;			\
3013 	frm[1] = (v) >> 8;			\
3014 	frm += 2;				\
3015 } while (0)
3016 	struct ieee80211com *ic = ni->ni_ic;
3017 	struct ieee80211vap *vap = ni->ni_vap;
3018 	uint16_t caps, extcaps;
3019 	int rxmax, density;
3020 
3021 	/* HT capabilities */
3022 	caps = vap->iv_htcaps & 0xffff;
3023 	/*
3024 	 * Note channel width depends on whether we are operating as
3025 	 * a sta or not.  When operating as a sta we are generating
3026 	 * a request based on our desired configuration.  Otherwise
3027 	 * we are operational and the channel attributes identify
3028 	 * how we've been setup (which might be different if a fixed
3029 	 * channel is specified).
3030 	 */
3031 	if (vap->iv_opmode == IEEE80211_M_STA) {
3032 		/* override 20/40 use based on config */
3033 		if (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)
3034 			caps |= IEEE80211_HTCAP_CHWIDTH40;
3035 		else
3036 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
3037 
3038 		/* Start by using the advertised settings */
3039 		rxmax = MS(ni->ni_htparam, IEEE80211_HTCAP_MAXRXAMPDU);
3040 		density = MS(ni->ni_htparam, IEEE80211_HTCAP_MPDUDENSITY);
3041 
3042 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_11N,
3043 		    "%s: advertised rxmax=%d, density=%d, vap rxmax=%d, density=%d\n",
3044 		    __func__,
3045 		    rxmax,
3046 		    density,
3047 		    vap->iv_ampdu_rxmax,
3048 		    vap->iv_ampdu_density);
3049 
3050 		/* Cap at VAP rxmax */
3051 		if (rxmax > vap->iv_ampdu_rxmax)
3052 			rxmax = vap->iv_ampdu_rxmax;
3053 
3054 		/*
3055 		 * If the VAP ampdu density value greater, use that.
3056 		 *
3057 		 * (Larger density value == larger minimum gap between A-MPDU
3058 		 * subframes.)
3059 		 */
3060 		if (vap->iv_ampdu_density > density)
3061 			density = vap->iv_ampdu_density;
3062 
3063 		/*
3064 		 * NB: Hardware might support HT40 on some but not all
3065 		 * channels. We can't determine this earlier because only
3066 		 * after association the channel is upgraded to HT based
3067 		 * on the negotiated capabilities.
3068 		 */
3069 		if (ni->ni_chan != IEEE80211_CHAN_ANYC &&
3070 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40U) == NULL &&
3071 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40D) == NULL)
3072 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
3073 	} else {
3074 		/* override 20/40 use based on current channel */
3075 		if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
3076 			caps |= IEEE80211_HTCAP_CHWIDTH40;
3077 		else
3078 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
3079 
3080 		/* XXX TODO should it start by using advertised settings? */
3081 		rxmax = vap->iv_ampdu_rxmax;
3082 		density = vap->iv_ampdu_density;
3083 	}
3084 
3085 	/* adjust short GI based on channel and config */
3086 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20) == 0)
3087 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
3088 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40) == 0 ||
3089 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
3090 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
3091 
3092 	/* adjust STBC based on receive capabilities */
3093 	if ((vap->iv_flags_ht & IEEE80211_FHT_STBC_RX) == 0)
3094 		caps &= ~IEEE80211_HTCAP_RXSTBC;
3095 
3096 	/* adjust LDPC based on receive capabilites */
3097 	if ((vap->iv_flags_ht & IEEE80211_FHT_LDPC_RX) == 0)
3098 		caps &= ~IEEE80211_HTCAP_LDPC;
3099 
3100 	ADDSHORT(frm, caps);
3101 
3102 	/* HT parameters */
3103 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
3104 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
3105 	     ;
3106 	frm++;
3107 
3108 	/* pre-zero remainder of ie */
3109 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
3110 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
3111 
3112 	/* supported MCS set */
3113 	/*
3114 	 * XXX: For sta mode the rate set should be restricted based
3115 	 * on the AP's capabilities, but ni_htrates isn't setup when
3116 	 * we're called to form an AssocReq frame so for now we're
3117 	 * restricted to the device capabilities.
3118 	 */
3119 	ieee80211_set_mcsset(ni->ni_ic, frm);
3120 
3121 	frm += __offsetof(struct ieee80211_ie_htcap, hc_extcap) -
3122 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
3123 
3124 	/* HT extended capabilities */
3125 	extcaps = vap->iv_htextcaps & 0xffff;
3126 
3127 	ADDSHORT(frm, extcaps);
3128 
3129 	frm += sizeof(struct ieee80211_ie_htcap) -
3130 		__offsetof(struct ieee80211_ie_htcap, hc_txbf);
3131 
3132 	return frm;
3133 #undef ADDSHORT
3134 }
3135 
3136 /*
3137  * Add 802.11n HT capabilities information element
3138  */
3139 uint8_t *
3140 ieee80211_add_htcap(uint8_t *frm, struct ieee80211_node *ni)
3141 {
3142 	frm[0] = IEEE80211_ELEMID_HTCAP;
3143 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
3144 	return ieee80211_add_htcap_body(frm + 2, ni);
3145 }
3146 
3147 /*
3148  * Non-associated probe request - add HT capabilities based on
3149  * the current channel configuration.
3150  */
3151 static uint8_t *
3152 ieee80211_add_htcap_body_ch(uint8_t *frm, struct ieee80211vap *vap,
3153     struct ieee80211_channel *c)
3154 {
3155 #define	ADDSHORT(frm, v) do {			\
3156 	frm[0] = (v) & 0xff;			\
3157 	frm[1] = (v) >> 8;			\
3158 	frm += 2;				\
3159 } while (0)
3160 	struct ieee80211com *ic = vap->iv_ic;
3161 	uint16_t caps, extcaps;
3162 	int rxmax, density;
3163 
3164 	/* HT capabilities */
3165 	caps = vap->iv_htcaps & 0xffff;
3166 
3167 	/*
3168 	 * We don't use this in STA mode; only in IBSS mode.
3169 	 * So in IBSS mode we base our HTCAP flags on the
3170 	 * given channel.
3171 	 */
3172 
3173 	/* override 20/40 use based on current channel */
3174 	if (IEEE80211_IS_CHAN_HT40(c))
3175 		caps |= IEEE80211_HTCAP_CHWIDTH40;
3176 	else
3177 		caps &= ~IEEE80211_HTCAP_CHWIDTH40;
3178 
3179 	/* Use the currently configured values */
3180 	rxmax = vap->iv_ampdu_rxmax;
3181 	density = vap->iv_ampdu_density;
3182 
3183 	/* adjust short GI based on channel and config */
3184 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20) == 0)
3185 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
3186 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40) == 0 ||
3187 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
3188 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
3189 	ADDSHORT(frm, caps);
3190 
3191 	/* HT parameters */
3192 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
3193 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
3194 	     ;
3195 	frm++;
3196 
3197 	/* pre-zero remainder of ie */
3198 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
3199 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
3200 
3201 	/* supported MCS set */
3202 	/*
3203 	 * XXX: For sta mode the rate set should be restricted based
3204 	 * on the AP's capabilities, but ni_htrates isn't setup when
3205 	 * we're called to form an AssocReq frame so for now we're
3206 	 * restricted to the device capabilities.
3207 	 */
3208 	ieee80211_set_mcsset(ic, frm);
3209 
3210 	frm += __offsetof(struct ieee80211_ie_htcap, hc_extcap) -
3211 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
3212 
3213 	/* HT extended capabilities */
3214 	extcaps = vap->iv_htextcaps & 0xffff;
3215 
3216 	ADDSHORT(frm, extcaps);
3217 
3218 	frm += sizeof(struct ieee80211_ie_htcap) -
3219 		__offsetof(struct ieee80211_ie_htcap, hc_txbf);
3220 
3221 	return frm;
3222 #undef ADDSHORT
3223 }
3224 
3225 /*
3226  * Add 802.11n HT capabilities information element
3227  */
3228 uint8_t *
3229 ieee80211_add_htcap_ch(uint8_t *frm, struct ieee80211vap *vap,
3230     struct ieee80211_channel *c)
3231 {
3232 	frm[0] = IEEE80211_ELEMID_HTCAP;
3233 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
3234 	return ieee80211_add_htcap_body_ch(frm + 2, vap, c);
3235 }
3236 
3237 /*
3238  * Add Broadcom OUI wrapped standard HTCAP ie; this is
3239  * used for compatibility w/ pre-draft implementations.
3240  */
3241 uint8_t *
3242 ieee80211_add_htcap_vendor(uint8_t *frm, struct ieee80211_node *ni)
3243 {
3244 	frm[0] = IEEE80211_ELEMID_VENDOR;
3245 	frm[1] = 4 + sizeof(struct ieee80211_ie_htcap) - 2;
3246 	frm[2] = (BCM_OUI >> 0) & 0xff;
3247 	frm[3] = (BCM_OUI >> 8) & 0xff;
3248 	frm[4] = (BCM_OUI >> 16) & 0xff;
3249 	frm[5] = BCM_OUI_HTCAP;
3250 	return ieee80211_add_htcap_body(frm + 6, ni);
3251 }
3252 
3253 /*
3254  * Construct the MCS bit mask of basic rates
3255  * for inclusion in an HT information element.
3256  */
3257 static void
3258 ieee80211_set_basic_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
3259 {
3260 	int i;
3261 
3262 	for (i = 0; i < rs->rs_nrates; i++) {
3263 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
3264 		if ((rs->rs_rates[i] & IEEE80211_RATE_BASIC) &&
3265 		    r < IEEE80211_HTRATE_MAXSIZE) {
3266 			/* NB: this assumes a particular implementation */
3267 			setbit(frm, r);
3268 		}
3269 	}
3270 }
3271 
3272 /*
3273  * Update the HTINFO ie for a beacon frame.
3274  */
3275 void
3276 ieee80211_ht_update_beacon(struct ieee80211vap *vap,
3277 	struct ieee80211_beacon_offsets *bo)
3278 {
3279 #define	PROTMODE	(IEEE80211_HTINFO_OPMODE|IEEE80211_HTINFO_NONHT_PRESENT)
3280 	struct ieee80211_node *ni;
3281 	const struct ieee80211_channel *bsschan;
3282 	struct ieee80211com *ic = vap->iv_ic;
3283 	struct ieee80211_ie_htinfo *ht =
3284 	   (struct ieee80211_ie_htinfo *) bo->bo_htinfo;
3285 
3286 	ni = ieee80211_ref_node(vap->iv_bss);
3287 	bsschan = ni->ni_chan;
3288 
3289 	/* XXX only update on channel change */
3290 	ht->hi_ctrlchannel = ieee80211_chan2ieee(ic, bsschan);
3291 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
3292 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PERM;
3293 	else
3294 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PROH;
3295 	if (IEEE80211_IS_CHAN_HT40U(bsschan))
3296 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
3297 	else if (IEEE80211_IS_CHAN_HT40D(bsschan))
3298 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_BELOW;
3299 	else
3300 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_NONE;
3301 	if (IEEE80211_IS_CHAN_HT40(bsschan))
3302 		ht->hi_byte1 |= IEEE80211_HTINFO_TXWIDTH_2040;
3303 
3304 	/* protection mode */
3305 	ht->hi_byte2 = (ht->hi_byte2 &~ PROTMODE) | ic->ic_curhtprotmode;
3306 
3307 	ieee80211_free_node(ni);
3308 
3309 	/* XXX propagate to vendor ie's */
3310 #undef PROTMODE
3311 }
3312 
3313 /*
3314  * Add body of an HTINFO information element.
3315  *
3316  * NB: We don't use struct ieee80211_ie_htinfo because we can
3317  * be called to fillin both a standard ie and a compat ie that
3318  * has a vendor OUI at the front.
3319  */
3320 static uint8_t *
3321 ieee80211_add_htinfo_body(uint8_t *frm, struct ieee80211_node *ni)
3322 {
3323 	struct ieee80211vap *vap = ni->ni_vap;
3324 	struct ieee80211com *ic = ni->ni_ic;
3325 
3326 	/* pre-zero remainder of ie */
3327 	memset(frm, 0, sizeof(struct ieee80211_ie_htinfo) - 2);
3328 
3329 	/* primary/control channel center */
3330 	*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
3331 
3332 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
3333 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PERM;
3334 	else
3335 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PROH;
3336 	if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
3337 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
3338 	else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
3339 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_BELOW;
3340 	else
3341 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_NONE;
3342 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
3343 		frm[0] |= IEEE80211_HTINFO_TXWIDTH_2040;
3344 
3345 	frm[1] = ic->ic_curhtprotmode;
3346 
3347 	frm += 5;
3348 
3349 	/* basic MCS set */
3350 	ieee80211_set_basic_htrates(frm, &ni->ni_htrates);
3351 	frm += sizeof(struct ieee80211_ie_htinfo) -
3352 		__offsetof(struct ieee80211_ie_htinfo, hi_basicmcsset);
3353 	return frm;
3354 }
3355 
3356 /*
3357  * Add 802.11n HT information element.
3358  */
3359 uint8_t *
3360 ieee80211_add_htinfo(uint8_t *frm, struct ieee80211_node *ni)
3361 {
3362 	frm[0] = IEEE80211_ELEMID_HTINFO;
3363 	frm[1] = sizeof(struct ieee80211_ie_htinfo) - 2;
3364 	return ieee80211_add_htinfo_body(frm + 2, ni);
3365 }
3366 
3367 /*
3368  * Add Broadcom OUI wrapped standard HTINFO ie; this is
3369  * used for compatibility w/ pre-draft implementations.
3370  */
3371 uint8_t *
3372 ieee80211_add_htinfo_vendor(uint8_t *frm, struct ieee80211_node *ni)
3373 {
3374 	frm[0] = IEEE80211_ELEMID_VENDOR;
3375 	frm[1] = 4 + sizeof(struct ieee80211_ie_htinfo) - 2;
3376 	frm[2] = (BCM_OUI >> 0) & 0xff;
3377 	frm[3] = (BCM_OUI >> 8) & 0xff;
3378 	frm[4] = (BCM_OUI >> 16) & 0xff;
3379 	frm[5] = BCM_OUI_HTINFO;
3380 	return ieee80211_add_htinfo_body(frm + 6, ni);
3381 }
3382