xref: /freebsd/sys/net80211/ieee80211_ht.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*-
2  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #ifdef __FreeBSD__
28 __FBSDID("$FreeBSD$");
29 #endif
30 
31 /*
32  * IEEE 802.11n protocol support.
33  */
34 
35 #include "opt_inet.h"
36 #include "opt_wlan.h"
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/endian.h>
42 
43 #include <sys/socket.h>
44 
45 #include <net/if.h>
46 #include <net/if_var.h>
47 #include <net/if_media.h>
48 #include <net/ethernet.h>
49 
50 #include <net80211/ieee80211_var.h>
51 #include <net80211/ieee80211_action.h>
52 #include <net80211/ieee80211_input.h>
53 
54 /* define here, used throughout file */
55 #define	MS(_v, _f)	(((_v) & _f) >> _f##_S)
56 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
57 
58 const struct ieee80211_mcs_rates ieee80211_htrates[IEEE80211_HTRATE_MAXSIZE] = {
59 	{  13,  14,   27,   30 },	/* MCS 0 */
60 	{  26,  29,   54,   60 },	/* MCS 1 */
61 	{  39,  43,   81,   90 },	/* MCS 2 */
62 	{  52,  58,  108,  120 },	/* MCS 3 */
63 	{  78,  87,  162,  180 },	/* MCS 4 */
64 	{ 104, 116,  216,  240 },	/* MCS 5 */
65 	{ 117, 130,  243,  270 },	/* MCS 6 */
66 	{ 130, 144,  270,  300 },	/* MCS 7 */
67 	{  26,  29,   54,   60 },	/* MCS 8 */
68 	{  52,  58,  108,  120 },	/* MCS 9 */
69 	{  78,  87,  162,  180 },	/* MCS 10 */
70 	{ 104, 116,  216,  240 },	/* MCS 11 */
71 	{ 156, 173,  324,  360 },	/* MCS 12 */
72 	{ 208, 231,  432,  480 },	/* MCS 13 */
73 	{ 234, 260,  486,  540 },	/* MCS 14 */
74 	{ 260, 289,  540,  600 },	/* MCS 15 */
75 	{  39,  43,   81,   90 },	/* MCS 16 */
76 	{  78,  87,  162,  180 },	/* MCS 17 */
77 	{ 117, 130,  243,  270 },	/* MCS 18 */
78 	{ 156, 173,  324,  360 },	/* MCS 19 */
79 	{ 234, 260,  486,  540 },	/* MCS 20 */
80 	{ 312, 347,  648,  720 },	/* MCS 21 */
81 	{ 351, 390,  729,  810 },	/* MCS 22 */
82 	{ 390, 433,  810,  900 },	/* MCS 23 */
83 	{  52,  58,  108,  120 },	/* MCS 24 */
84 	{ 104, 116,  216,  240 },	/* MCS 25 */
85 	{ 156, 173,  324,  360 },	/* MCS 26 */
86 	{ 208, 231,  432,  480 },	/* MCS 27 */
87 	{ 312, 347,  648,  720 },	/* MCS 28 */
88 	{ 416, 462,  864,  960 },	/* MCS 29 */
89 	{ 468, 520,  972, 1080 },	/* MCS 30 */
90 	{ 520, 578, 1080, 1200 },	/* MCS 31 */
91 	{   0,   0,   12,   13 },	/* MCS 32 */
92 	{  78,  87,  162,  180 },	/* MCS 33 */
93 	{ 104, 116,  216,  240 },	/* MCS 34 */
94 	{ 130, 144,  270,  300 },	/* MCS 35 */
95 	{ 117, 130,  243,  270 },	/* MCS 36 */
96 	{ 156, 173,  324,  360 },	/* MCS 37 */
97 	{ 195, 217,  405,  450 },	/* MCS 38 */
98 	{ 104, 116,  216,  240 },	/* MCS 39 */
99 	{ 130, 144,  270,  300 },	/* MCS 40 */
100 	{ 130, 144,  270,  300 },	/* MCS 41 */
101 	{ 156, 173,  324,  360 },	/* MCS 42 */
102 	{ 182, 202,  378,  420 },	/* MCS 43 */
103 	{ 182, 202,  378,  420 },	/* MCS 44 */
104 	{ 208, 231,  432,  480 },	/* MCS 45 */
105 	{ 156, 173,  324,  360 },	/* MCS 46 */
106 	{ 195, 217,  405,  450 },	/* MCS 47 */
107 	{ 195, 217,  405,  450 },	/* MCS 48 */
108 	{ 234, 260,  486,  540 },	/* MCS 49 */
109 	{ 273, 303,  567,  630 },	/* MCS 50 */
110 	{ 273, 303,  567,  630 },	/* MCS 51 */
111 	{ 312, 347,  648,  720 },	/* MCS 52 */
112 	{ 130, 144,  270,  300 },	/* MCS 53 */
113 	{ 156, 173,  324,  360 },	/* MCS 54 */
114 	{ 182, 202,  378,  420 },	/* MCS 55 */
115 	{ 156, 173,  324,  360 },	/* MCS 56 */
116 	{ 182, 202,  378,  420 },	/* MCS 57 */
117 	{ 208, 231,  432,  480 },	/* MCS 58 */
118 	{ 234, 260,  486,  540 },	/* MCS 59 */
119 	{ 208, 231,  432,  480 },	/* MCS 60 */
120 	{ 234, 260,  486,  540 },	/* MCS 61 */
121 	{ 260, 289,  540,  600 },	/* MCS 62 */
122 	{ 260, 289,  540,  600 },	/* MCS 63 */
123 	{ 286, 318,  594,  660 },	/* MCS 64 */
124 	{ 195, 217,  405,  450 },	/* MCS 65 */
125 	{ 234, 260,  486,  540 },	/* MCS 66 */
126 	{ 273, 303,  567,  630 },	/* MCS 67 */
127 	{ 234, 260,  486,  540 },	/* MCS 68 */
128 	{ 273, 303,  567,  630 },	/* MCS 69 */
129 	{ 312, 347,  648,  720 },	/* MCS 70 */
130 	{ 351, 390,  729,  810 },	/* MCS 71 */
131 	{ 312, 347,  648,  720 },	/* MCS 72 */
132 	{ 351, 390,  729,  810 },	/* MCS 73 */
133 	{ 390, 433,  810,  900 },	/* MCS 74 */
134 	{ 390, 433,  810,  900 },	/* MCS 75 */
135 	{ 429, 477,  891,  990 },	/* MCS 76 */
136 };
137 
138 #ifdef IEEE80211_AMPDU_AGE
139 static	int ieee80211_ampdu_age = -1;	/* threshold for ampdu reorder q (ms) */
140 SYSCTL_PROC(_net_wlan, OID_AUTO, ampdu_age, CTLTYPE_INT | CTLFLAG_RW,
141 	&ieee80211_ampdu_age, 0, ieee80211_sysctl_msecs_ticks, "I",
142 	"AMPDU max reorder age (ms)");
143 #endif
144 
145 static	int ieee80211_recv_bar_ena = 1;
146 SYSCTL_INT(_net_wlan, OID_AUTO, recv_bar, CTLFLAG_RW, &ieee80211_recv_bar_ena,
147 	    0, "BAR frame processing (ena/dis)");
148 
149 static	int ieee80211_addba_timeout = -1;/* timeout for ADDBA response */
150 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_timeout, CTLTYPE_INT | CTLFLAG_RW,
151 	&ieee80211_addba_timeout, 0, ieee80211_sysctl_msecs_ticks, "I",
152 	"ADDBA request timeout (ms)");
153 static	int ieee80211_addba_backoff = -1;/* backoff after max ADDBA requests */
154 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_backoff, CTLTYPE_INT | CTLFLAG_RW,
155 	&ieee80211_addba_backoff, 0, ieee80211_sysctl_msecs_ticks, "I",
156 	"ADDBA request backoff (ms)");
157 static	int ieee80211_addba_maxtries = 3;/* max ADDBA requests before backoff */
158 SYSCTL_INT(_net_wlan, OID_AUTO, addba_maxtries, CTLFLAG_RW,
159 	&ieee80211_addba_maxtries, 0, "max ADDBA requests sent before backoff");
160 
161 static	int ieee80211_bar_timeout = -1;	/* timeout waiting for BAR response */
162 static	int ieee80211_bar_maxtries = 50;/* max BAR requests before DELBA */
163 
164 static	ieee80211_recv_action_func ht_recv_action_ba_addba_request;
165 static	ieee80211_recv_action_func ht_recv_action_ba_addba_response;
166 static	ieee80211_recv_action_func ht_recv_action_ba_delba;
167 static	ieee80211_recv_action_func ht_recv_action_ht_mimopwrsave;
168 static	ieee80211_recv_action_func ht_recv_action_ht_txchwidth;
169 
170 static	ieee80211_send_action_func ht_send_action_ba_addba;
171 static	ieee80211_send_action_func ht_send_action_ba_delba;
172 static	ieee80211_send_action_func ht_send_action_ht_txchwidth;
173 
174 static void
175 ieee80211_ht_init(void)
176 {
177 	/*
178 	 * Setup HT parameters that depends on the clock frequency.
179 	 */
180 #ifdef IEEE80211_AMPDU_AGE
181 	ieee80211_ampdu_age = msecs_to_ticks(500);
182 #endif
183 	ieee80211_addba_timeout = msecs_to_ticks(250);
184 	ieee80211_addba_backoff = msecs_to_ticks(10*1000);
185 	ieee80211_bar_timeout = msecs_to_ticks(250);
186 	/*
187 	 * Register action frame handlers.
188 	 */
189 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
190 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_recv_action_ba_addba_request);
191 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
192 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_recv_action_ba_addba_response);
193 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
194 	    IEEE80211_ACTION_BA_DELBA, ht_recv_action_ba_delba);
195 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
196 	    IEEE80211_ACTION_HT_MIMOPWRSAVE, ht_recv_action_ht_mimopwrsave);
197 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
198 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_recv_action_ht_txchwidth);
199 
200 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
201 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_send_action_ba_addba);
202 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
203 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_send_action_ba_addba);
204 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
205 	    IEEE80211_ACTION_BA_DELBA, ht_send_action_ba_delba);
206 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_HT,
207 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_send_action_ht_txchwidth);
208 }
209 SYSINIT(wlan_ht, SI_SUB_DRIVERS, SI_ORDER_FIRST, ieee80211_ht_init, NULL);
210 
211 static int ieee80211_ampdu_enable(struct ieee80211_node *ni,
212 	struct ieee80211_tx_ampdu *tap);
213 static int ieee80211_addba_request(struct ieee80211_node *ni,
214 	struct ieee80211_tx_ampdu *tap,
215 	int dialogtoken, int baparamset, int batimeout);
216 static int ieee80211_addba_response(struct ieee80211_node *ni,
217 	struct ieee80211_tx_ampdu *tap,
218 	int code, int baparamset, int batimeout);
219 static void ieee80211_addba_stop(struct ieee80211_node *ni,
220 	struct ieee80211_tx_ampdu *tap);
221 static void null_addba_response_timeout(struct ieee80211_node *ni,
222 	struct ieee80211_tx_ampdu *tap);
223 
224 static void ieee80211_bar_response(struct ieee80211_node *ni,
225 	struct ieee80211_tx_ampdu *tap, int status);
226 static void ampdu_tx_stop(struct ieee80211_tx_ampdu *tap);
227 static void bar_stop_timer(struct ieee80211_tx_ampdu *tap);
228 static int ampdu_rx_start(struct ieee80211_node *, struct ieee80211_rx_ampdu *,
229 	int baparamset, int batimeout, int baseqctl);
230 static void ampdu_rx_stop(struct ieee80211_node *, struct ieee80211_rx_ampdu *);
231 
232 void
233 ieee80211_ht_attach(struct ieee80211com *ic)
234 {
235 	/* setup default aggregation policy */
236 	ic->ic_recv_action = ieee80211_recv_action;
237 	ic->ic_send_action = ieee80211_send_action;
238 	ic->ic_ampdu_enable = ieee80211_ampdu_enable;
239 	ic->ic_addba_request = ieee80211_addba_request;
240 	ic->ic_addba_response = ieee80211_addba_response;
241 	ic->ic_addba_response_timeout = null_addba_response_timeout;
242 	ic->ic_addba_stop = ieee80211_addba_stop;
243 	ic->ic_bar_response = ieee80211_bar_response;
244 	ic->ic_ampdu_rx_start = ampdu_rx_start;
245 	ic->ic_ampdu_rx_stop = ampdu_rx_stop;
246 
247 	ic->ic_htprotmode = IEEE80211_PROT_RTSCTS;
248 	ic->ic_curhtprotmode = IEEE80211_HTINFO_OPMODE_PURE;
249 }
250 
251 void
252 ieee80211_ht_detach(struct ieee80211com *ic)
253 {
254 }
255 
256 void
257 ieee80211_ht_vattach(struct ieee80211vap *vap)
258 {
259 
260 	/* driver can override defaults */
261 	vap->iv_ampdu_rxmax = IEEE80211_HTCAP_MAXRXAMPDU_8K;
262 	vap->iv_ampdu_density = IEEE80211_HTCAP_MPDUDENSITY_NA;
263 	vap->iv_ampdu_limit = vap->iv_ampdu_rxmax;
264 	vap->iv_amsdu_limit = vap->iv_htcaps & IEEE80211_HTCAP_MAXAMSDU;
265 	/* tx aggregation traffic thresholds */
266 	vap->iv_ampdu_mintraffic[WME_AC_BK] = 128;
267 	vap->iv_ampdu_mintraffic[WME_AC_BE] = 64;
268 	vap->iv_ampdu_mintraffic[WME_AC_VO] = 32;
269 	vap->iv_ampdu_mintraffic[WME_AC_VI] = 32;
270 
271 	if (vap->iv_htcaps & IEEE80211_HTC_HT) {
272 		/*
273 		 * Device is HT capable; enable all HT-related
274 		 * facilities by default.
275 		 * XXX these choices may be too aggressive.
276 		 */
277 		vap->iv_flags_ht |= IEEE80211_FHT_HT
278 				 |  IEEE80211_FHT_HTCOMPAT
279 				 ;
280 		if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI20)
281 			vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI20;
282 		/* XXX infer from channel list? */
283 		if (vap->iv_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
284 			vap->iv_flags_ht |= IEEE80211_FHT_USEHT40;
285 			if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI40)
286 				vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI40;
287 		}
288 		/* enable RIFS if capable */
289 		if (vap->iv_htcaps & IEEE80211_HTC_RIFS)
290 			vap->iv_flags_ht |= IEEE80211_FHT_RIFS;
291 
292 		/* NB: A-MPDU and A-MSDU rx are mandated, these are tx only */
293 		vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_RX;
294 		if (vap->iv_htcaps & IEEE80211_HTC_AMPDU)
295 			vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_TX;
296 		vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_RX;
297 		if (vap->iv_htcaps & IEEE80211_HTC_AMSDU)
298 			vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_TX;
299 	}
300 	/* NB: disable default legacy WDS, too many issues right now */
301 	if (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)
302 		vap->iv_flags_ht &= ~IEEE80211_FHT_HT;
303 }
304 
305 void
306 ieee80211_ht_vdetach(struct ieee80211vap *vap)
307 {
308 }
309 
310 static int
311 ht_getrate(struct ieee80211com *ic, int index, enum ieee80211_phymode mode,
312     int ratetype)
313 {
314 	int mword, rate;
315 
316 	mword = ieee80211_rate2media(ic, index | IEEE80211_RATE_MCS, mode);
317 	if (IFM_SUBTYPE(mword) != IFM_IEEE80211_MCS)
318 		return (0);
319 	switch (ratetype) {
320 	case 0:
321 		rate = ieee80211_htrates[index].ht20_rate_800ns;
322 		break;
323 	case 1:
324 		rate = ieee80211_htrates[index].ht20_rate_400ns;
325 		break;
326 	case 2:
327 		rate = ieee80211_htrates[index].ht40_rate_800ns;
328 		break;
329 	default:
330 		rate = ieee80211_htrates[index].ht40_rate_400ns;
331 		break;
332 	}
333 	return (rate);
334 }
335 
336 static struct printranges {
337 	int	minmcs;
338 	int	maxmcs;
339 	int	txstream;
340 	int	ratetype;
341 	int	htcapflags;
342 } ranges[] = {
343 	{  0,  7, 1, 0, 0 },
344 	{  8, 15, 2, 0, 0 },
345 	{ 16, 23, 3, 0, 0 },
346 	{ 24, 31, 4, 0, 0 },
347 	{ 32,  0, 1, 2, IEEE80211_HTC_TXMCS32 },
348 	{ 33, 38, 2, 0, IEEE80211_HTC_TXUNEQUAL },
349 	{ 39, 52, 3, 0, IEEE80211_HTC_TXUNEQUAL },
350 	{ 53, 76, 4, 0, IEEE80211_HTC_TXUNEQUAL },
351 	{  0,  0, 0, 0, 0 },
352 };
353 
354 static void
355 ht_rateprint(struct ieee80211com *ic, enum ieee80211_phymode mode, int ratetype)
356 {
357 	int minrate, maxrate;
358 	struct printranges *range;
359 
360 	for (range = ranges; range->txstream != 0; range++) {
361 		if (ic->ic_txstream < range->txstream)
362 			continue;
363 		if (range->htcapflags &&
364 		    (ic->ic_htcaps & range->htcapflags) == 0)
365 			continue;
366 		if (ratetype < range->ratetype)
367 			continue;
368 		minrate = ht_getrate(ic, range->minmcs, mode, ratetype);
369 		maxrate = ht_getrate(ic, range->maxmcs, mode, ratetype);
370 		if (range->maxmcs) {
371 			ic_printf(ic, "MCS %d-%d: %d%sMbps - %d%sMbps\n",
372 			    range->minmcs, range->maxmcs,
373 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""),
374 			    maxrate/2, ((maxrate & 0x1) != 0 ? ".5" : ""));
375 		} else {
376 			ic_printf(ic, "MCS %d: %d%sMbps\n", range->minmcs,
377 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""));
378 		}
379 	}
380 }
381 
382 static void
383 ht_announce(struct ieee80211com *ic, enum ieee80211_phymode mode)
384 {
385 	const char *modestr = ieee80211_phymode_name[mode];
386 
387 	ic_printf(ic, "%s MCS 20MHz\n", modestr);
388 	ht_rateprint(ic, mode, 0);
389 	if (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20) {
390 		ic_printf(ic, "%s MCS 20MHz SGI\n", modestr);
391 		ht_rateprint(ic, mode, 1);
392 	}
393 	if (ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
394 		ic_printf(ic, "%s MCS 40MHz:\n", modestr);
395 		ht_rateprint(ic, mode, 2);
396 	}
397 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
398 	    (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40)) {
399 		ic_printf(ic, "%s MCS 40MHz SGI:\n", modestr);
400 		ht_rateprint(ic, mode, 3);
401 	}
402 }
403 
404 void
405 ieee80211_ht_announce(struct ieee80211com *ic)
406 {
407 
408 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA) ||
409 	    isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
410 		ic_printf(ic, "%dT%dR\n", ic->ic_txstream, ic->ic_rxstream);
411 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
412 		ht_announce(ic, IEEE80211_MODE_11NA);
413 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
414 		ht_announce(ic, IEEE80211_MODE_11NG);
415 }
416 
417 static struct ieee80211_htrateset htrateset;
418 
419 const struct ieee80211_htrateset *
420 ieee80211_get_suphtrates(struct ieee80211com *ic,
421     const struct ieee80211_channel *c)
422 {
423 #define	ADDRATE(x)	do {						\
424 	htrateset.rs_rates[htrateset.rs_nrates] = x;			\
425 	htrateset.rs_nrates++;						\
426 } while (0)
427 	int i;
428 
429 	memset(&htrateset, 0, sizeof(struct ieee80211_htrateset));
430 	for (i = 0; i < ic->ic_txstream * 8; i++)
431 		ADDRATE(i);
432 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
433 	    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32))
434 		ADDRATE(32);
435 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
436 		if (ic->ic_txstream >= 2) {
437 			 for (i = 33; i <= 38; i++)
438 				ADDRATE(i);
439 		}
440 		if (ic->ic_txstream >= 3) {
441 			for (i = 39; i <= 52; i++)
442 				ADDRATE(i);
443 		}
444 		if (ic->ic_txstream == 4) {
445 			for (i = 53; i <= 76; i++)
446 				ADDRATE(i);
447 		}
448 	}
449 	return &htrateset;
450 #undef	ADDRATE
451 }
452 
453 /*
454  * Receive processing.
455  */
456 
457 /*
458  * Decap the encapsulated A-MSDU frames and dispatch all but
459  * the last for delivery.  The last frame is returned for
460  * delivery via the normal path.
461  */
462 struct mbuf *
463 ieee80211_decap_amsdu(struct ieee80211_node *ni, struct mbuf *m)
464 {
465 	struct ieee80211vap *vap = ni->ni_vap;
466 	int framelen;
467 	struct mbuf *n;
468 
469 	/* discard 802.3 header inserted by ieee80211_decap */
470 	m_adj(m, sizeof(struct ether_header));
471 
472 	vap->iv_stats.is_amsdu_decap++;
473 
474 	for (;;) {
475 		/*
476 		 * Decap the first frame, bust it apart from the
477 		 * remainder and deliver.  We leave the last frame
478 		 * delivery to the caller (for consistency with other
479 		 * code paths, could also do it here).
480 		 */
481 		m = ieee80211_decap1(m, &framelen);
482 		if (m == NULL) {
483 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
484 			    ni->ni_macaddr, "a-msdu", "%s", "decap failed");
485 			vap->iv_stats.is_amsdu_tooshort++;
486 			return NULL;
487 		}
488 		if (m->m_pkthdr.len == framelen)
489 			break;
490 		n = m_split(m, framelen, M_NOWAIT);
491 		if (n == NULL) {
492 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
493 			    ni->ni_macaddr, "a-msdu",
494 			    "%s", "unable to split encapsulated frames");
495 			vap->iv_stats.is_amsdu_split++;
496 			m_freem(m);			/* NB: must reclaim */
497 			return NULL;
498 		}
499 		vap->iv_deliver_data(vap, ni, m);
500 
501 		/*
502 		 * Remove frame contents; each intermediate frame
503 		 * is required to be aligned to a 4-byte boundary.
504 		 */
505 		m = n;
506 		m_adj(m, roundup2(framelen, 4) - framelen);	/* padding */
507 	}
508 	return m;				/* last delivered by caller */
509 }
510 
511 /*
512  * Purge all frames in the A-MPDU re-order queue.
513  */
514 static void
515 ampdu_rx_purge(struct ieee80211_rx_ampdu *rap)
516 {
517 	struct mbuf *m;
518 	int i;
519 
520 	for (i = 0; i < rap->rxa_wnd; i++) {
521 		m = rap->rxa_m[i];
522 		if (m != NULL) {
523 			rap->rxa_m[i] = NULL;
524 			rap->rxa_qbytes -= m->m_pkthdr.len;
525 			m_freem(m);
526 			if (--rap->rxa_qframes == 0)
527 				break;
528 		}
529 	}
530 	KASSERT(rap->rxa_qbytes == 0 && rap->rxa_qframes == 0,
531 	    ("lost %u data, %u frames on ampdu rx q",
532 	    rap->rxa_qbytes, rap->rxa_qframes));
533 }
534 
535 /*
536  * Start A-MPDU rx/re-order processing for the specified TID.
537  */
538 static int
539 ampdu_rx_start(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap,
540 	int baparamset, int batimeout, int baseqctl)
541 {
542 	int bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
543 
544 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
545 		/*
546 		 * AMPDU previously setup and not terminated with a DELBA,
547 		 * flush the reorder q's in case anything remains.
548 		 */
549 		ampdu_rx_purge(rap);
550 	}
551 	memset(rap, 0, sizeof(*rap));
552 	rap->rxa_wnd = (bufsiz == 0) ?
553 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
554 	rap->rxa_start = MS(baseqctl, IEEE80211_BASEQ_START);
555 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
556 
557 	return 0;
558 }
559 
560 /*
561  * Stop A-MPDU rx processing for the specified TID.
562  */
563 static void
564 ampdu_rx_stop(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
565 {
566 
567 	ampdu_rx_purge(rap);
568 	rap->rxa_flags &= ~(IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND);
569 }
570 
571 /*
572  * Dispatch a frame from the A-MPDU reorder queue.  The
573  * frame is fed back into ieee80211_input marked with an
574  * M_AMPDU_MPDU flag so it doesn't come back to us (it also
575  * permits ieee80211_input to optimize re-processing).
576  */
577 static __inline void
578 ampdu_dispatch(struct ieee80211_node *ni, struct mbuf *m)
579 {
580 	m->m_flags |= M_AMPDU_MPDU;	/* bypass normal processing */
581 	/* NB: rssi and noise are ignored w/ M_AMPDU_MPDU set */
582 	(void) ieee80211_input(ni, m, 0, 0);
583 }
584 
585 /*
586  * Dispatch as many frames as possible from the re-order queue.
587  * Frames will always be "at the front"; we process all frames
588  * up to the first empty slot in the window.  On completion we
589  * cleanup state if there are still pending frames in the current
590  * BA window.  We assume the frame at slot 0 is already handled
591  * by the caller; we always start at slot 1.
592  */
593 static void
594 ampdu_rx_dispatch(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni)
595 {
596 	struct ieee80211vap *vap = ni->ni_vap;
597 	struct mbuf *m;
598 	int i;
599 
600 	/* flush run of frames */
601 	for (i = 1; i < rap->rxa_wnd; i++) {
602 		m = rap->rxa_m[i];
603 		if (m == NULL)
604 			break;
605 		rap->rxa_m[i] = NULL;
606 		rap->rxa_qbytes -= m->m_pkthdr.len;
607 		rap->rxa_qframes--;
608 
609 		ampdu_dispatch(ni, m);
610 	}
611 	/*
612 	 * If frames remain, copy the mbuf pointers down so
613 	 * they correspond to the offsets in the new window.
614 	 */
615 	if (rap->rxa_qframes != 0) {
616 		int n = rap->rxa_qframes, j;
617 		for (j = i+1; j < rap->rxa_wnd; j++) {
618 			if (rap->rxa_m[j] != NULL) {
619 				rap->rxa_m[j-i] = rap->rxa_m[j];
620 				rap->rxa_m[j] = NULL;
621 				if (--n == 0)
622 					break;
623 			}
624 		}
625 		KASSERT(n == 0, ("lost %d frames", n));
626 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
627 	}
628 	/*
629 	 * Adjust the start of the BA window to
630 	 * reflect the frames just dispatched.
631 	 */
632 	rap->rxa_start = IEEE80211_SEQ_ADD(rap->rxa_start, i);
633 	vap->iv_stats.is_ampdu_rx_oor += i;
634 }
635 
636 #ifdef IEEE80211_AMPDU_AGE
637 /*
638  * Dispatch all frames in the A-MPDU re-order queue.
639  */
640 static void
641 ampdu_rx_flush(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
642 {
643 	struct ieee80211vap *vap = ni->ni_vap;
644 	struct mbuf *m;
645 	int i;
646 
647 	for (i = 0; i < rap->rxa_wnd; i++) {
648 		m = rap->rxa_m[i];
649 		if (m == NULL)
650 			continue;
651 		rap->rxa_m[i] = NULL;
652 		rap->rxa_qbytes -= m->m_pkthdr.len;
653 		rap->rxa_qframes--;
654 		vap->iv_stats.is_ampdu_rx_oor++;
655 
656 		ampdu_dispatch(ni, m);
657 		if (rap->rxa_qframes == 0)
658 			break;
659 	}
660 }
661 #endif /* IEEE80211_AMPDU_AGE */
662 
663 /*
664  * Dispatch all frames in the A-MPDU re-order queue
665  * preceding the specified sequence number.  This logic
666  * handles window moves due to a received MSDU or BAR.
667  */
668 static void
669 ampdu_rx_flush_upto(struct ieee80211_node *ni,
670 	struct ieee80211_rx_ampdu *rap, ieee80211_seq winstart)
671 {
672 	struct ieee80211vap *vap = ni->ni_vap;
673 	struct mbuf *m;
674 	ieee80211_seq seqno;
675 	int i;
676 
677 	/*
678 	 * Flush any complete MSDU's with a sequence number lower
679 	 * than winstart.  Gaps may exist.  Note that we may actually
680 	 * dispatch frames past winstart if a run continues; this is
681 	 * an optimization that avoids having to do a separate pass
682 	 * to dispatch frames after moving the BA window start.
683 	 */
684 	seqno = rap->rxa_start;
685 	for (i = 0; i < rap->rxa_wnd; i++) {
686 		m = rap->rxa_m[i];
687 		if (m != NULL) {
688 			rap->rxa_m[i] = NULL;
689 			rap->rxa_qbytes -= m->m_pkthdr.len;
690 			rap->rxa_qframes--;
691 			vap->iv_stats.is_ampdu_rx_oor++;
692 
693 			ampdu_dispatch(ni, m);
694 		} else {
695 			if (!IEEE80211_SEQ_BA_BEFORE(seqno, winstart))
696 				break;
697 		}
698 		seqno = IEEE80211_SEQ_INC(seqno);
699 	}
700 	/*
701 	 * If frames remain, copy the mbuf pointers down so
702 	 * they correspond to the offsets in the new window.
703 	 */
704 	if (rap->rxa_qframes != 0) {
705 		int n = rap->rxa_qframes, j;
706 
707 		/* NB: this loop assumes i > 0 and/or rxa_m[0] is NULL */
708 		KASSERT(rap->rxa_m[0] == NULL,
709 		    ("%s: BA window slot 0 occupied", __func__));
710 		for (j = i+1; j < rap->rxa_wnd; j++) {
711 			if (rap->rxa_m[j] != NULL) {
712 				rap->rxa_m[j-i] = rap->rxa_m[j];
713 				rap->rxa_m[j] = NULL;
714 				if (--n == 0)
715 					break;
716 			}
717 		}
718 		KASSERT(n == 0, ("%s: lost %d frames, qframes %d off %d "
719 		    "BA win <%d:%d> winstart %d",
720 		    __func__, n, rap->rxa_qframes, i, rap->rxa_start,
721 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
722 		    winstart));
723 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
724 	}
725 	/*
726 	 * Move the start of the BA window; we use the
727 	 * sequence number of the last MSDU that was
728 	 * passed up the stack+1 or winstart if stopped on
729 	 * a gap in the reorder buffer.
730 	 */
731 	rap->rxa_start = seqno;
732 }
733 
734 /*
735  * Process a received QoS data frame for an HT station.  Handle
736  * A-MPDU reordering: if this frame is received out of order
737  * and falls within the BA window hold onto it.  Otherwise if
738  * this frame completes a run, flush any pending frames.  We
739  * return 1 if the frame is consumed.  A 0 is returned if
740  * the frame should be processed normally by the caller.
741  */
742 int
743 ieee80211_ampdu_reorder(struct ieee80211_node *ni, struct mbuf *m)
744 {
745 #define	IEEE80211_FC0_QOSDATA \
746 	(IEEE80211_FC0_TYPE_DATA|IEEE80211_FC0_SUBTYPE_QOS|IEEE80211_FC0_VERSION_0)
747 #define	PROCESS		0	/* caller should process frame */
748 #define	CONSUMED	1	/* frame consumed, caller does nothing */
749 	struct ieee80211vap *vap = ni->ni_vap;
750 	struct ieee80211_qosframe *wh;
751 	struct ieee80211_rx_ampdu *rap;
752 	ieee80211_seq rxseq;
753 	uint8_t tid;
754 	int off;
755 
756 	KASSERT((m->m_flags & (M_AMPDU | M_AMPDU_MPDU)) == M_AMPDU,
757 	    ("!a-mpdu or already re-ordered, flags 0x%x", m->m_flags));
758 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
759 
760 	/* NB: m_len known to be sufficient */
761 	wh = mtod(m, struct ieee80211_qosframe *);
762 	if (wh->i_fc[0] != IEEE80211_FC0_QOSDATA) {
763 		/*
764 		 * Not QoS data, shouldn't get here but just
765 		 * return it to the caller for processing.
766 		 */
767 		return PROCESS;
768 	}
769 	if (IEEE80211_IS_DSTODS(wh))
770 		tid = ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0];
771 	else
772 		tid = wh->i_qos[0];
773 	tid &= IEEE80211_QOS_TID;
774 	rap = &ni->ni_rx_ampdu[tid];
775 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
776 		/*
777 		 * No ADDBA request yet, don't touch.
778 		 */
779 		return PROCESS;
780 	}
781 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
782 	if ((rxseq & IEEE80211_SEQ_FRAG_MASK) != 0) {
783 		/*
784 		 * Fragments are not allowed; toss.
785 		 */
786 		IEEE80211_DISCARD_MAC(vap,
787 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
788 		    "A-MPDU", "fragment, rxseq 0x%x tid %u%s", rxseq, tid,
789 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
790 		vap->iv_stats.is_ampdu_rx_drop++;
791 		IEEE80211_NODE_STAT(ni, rx_drop);
792 		m_freem(m);
793 		return CONSUMED;
794 	}
795 	rxseq >>= IEEE80211_SEQ_SEQ_SHIFT;
796 	rap->rxa_nframes++;
797 again:
798 	if (rxseq == rap->rxa_start) {
799 		/*
800 		 * First frame in window.
801 		 */
802 		if (rap->rxa_qframes != 0) {
803 			/*
804 			 * Dispatch as many packets as we can.
805 			 */
806 			KASSERT(rap->rxa_m[0] == NULL, ("unexpected dup"));
807 			ampdu_dispatch(ni, m);
808 			ampdu_rx_dispatch(rap, ni);
809 			return CONSUMED;
810 		} else {
811 			/*
812 			 * In order; advance window and notify
813 			 * caller to dispatch directly.
814 			 */
815 			rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
816 			return PROCESS;
817 		}
818 	}
819 	/*
820 	 * Frame is out of order; store if in the BA window.
821 	 */
822 	/* calculate offset in BA window */
823 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
824 	if (off < rap->rxa_wnd) {
825 		/*
826 		 * Common case (hopefully): in the BA window.
827 		 * Sec 9.10.7.6.2 a) (p.137)
828 		 */
829 #ifdef IEEE80211_AMPDU_AGE
830 		/*
831 		 * Check for frames sitting too long in the reorder queue.
832 		 * This should only ever happen if frames are not delivered
833 		 * without the sender otherwise notifying us (e.g. with a
834 		 * BAR to move the window).  Typically this happens because
835 		 * of vendor bugs that cause the sequence number to jump.
836 		 * When this happens we get a gap in the reorder queue that
837 		 * leaves frame sitting on the queue until they get pushed
838 		 * out due to window moves.  When the vendor does not send
839 		 * BAR this move only happens due to explicit packet sends
840 		 *
841 		 * NB: we only track the time of the oldest frame in the
842 		 * reorder q; this means that if we flush we might push
843 		 * frames that still "new"; if this happens then subsequent
844 		 * frames will result in BA window moves which cost something
845 		 * but is still better than a big throughput dip.
846 		 */
847 		if (rap->rxa_qframes != 0) {
848 			/* XXX honor batimeout? */
849 			if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
850 				/*
851 				 * Too long since we received the first
852 				 * frame; flush the reorder buffer.
853 				 */
854 				if (rap->rxa_qframes != 0) {
855 					vap->iv_stats.is_ampdu_rx_age +=
856 					    rap->rxa_qframes;
857 					ampdu_rx_flush(ni, rap);
858 				}
859 				rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
860 				return PROCESS;
861 			}
862 		} else {
863 			/*
864 			 * First frame, start aging timer.
865 			 */
866 			rap->rxa_age = ticks;
867 		}
868 #endif /* IEEE80211_AMPDU_AGE */
869 		/* save packet */
870 		if (rap->rxa_m[off] == NULL) {
871 			rap->rxa_m[off] = m;
872 			rap->rxa_qframes++;
873 			rap->rxa_qbytes += m->m_pkthdr.len;
874 			vap->iv_stats.is_ampdu_rx_reorder++;
875 		} else {
876 			IEEE80211_DISCARD_MAC(vap,
877 			    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
878 			    ni->ni_macaddr, "a-mpdu duplicate",
879 			    "seqno %u tid %u BA win <%u:%u>",
880 			    rxseq, tid, rap->rxa_start,
881 			    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1));
882 			vap->iv_stats.is_rx_dup++;
883 			IEEE80211_NODE_STAT(ni, rx_dup);
884 			m_freem(m);
885 		}
886 		return CONSUMED;
887 	}
888 	if (off < IEEE80211_SEQ_BA_RANGE) {
889 		/*
890 		 * Outside the BA window, but within range;
891 		 * flush the reorder q and move the window.
892 		 * Sec 9.10.7.6.2 b) (p.138)
893 		 */
894 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
895 		    "move BA win <%u:%u> (%u frames) rxseq %u tid %u",
896 		    rap->rxa_start,
897 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
898 		    rap->rxa_qframes, rxseq, tid);
899 		vap->iv_stats.is_ampdu_rx_move++;
900 
901 		/*
902 		 * The spec says to flush frames up to but not including:
903 		 * 	WinStart_B = rxseq - rap->rxa_wnd + 1
904 		 * Then insert the frame or notify the caller to process
905 		 * it immediately.  We can safely do this by just starting
906 		 * over again because we know the frame will now be within
907 		 * the BA window.
908 		 */
909 		/* NB: rxa_wnd known to be >0 */
910 		ampdu_rx_flush_upto(ni, rap,
911 		    IEEE80211_SEQ_SUB(rxseq, rap->rxa_wnd-1));
912 		goto again;
913 	} else {
914 		/*
915 		 * Outside the BA window and out of range; toss.
916 		 * Sec 9.10.7.6.2 c) (p.138)
917 		 */
918 		IEEE80211_DISCARD_MAC(vap,
919 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
920 		    "MPDU", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
921 		    rap->rxa_start,
922 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
923 		    rap->rxa_qframes, rxseq, tid,
924 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
925 		vap->iv_stats.is_ampdu_rx_drop++;
926 		IEEE80211_NODE_STAT(ni, rx_drop);
927 		m_freem(m);
928 		return CONSUMED;
929 	}
930 #undef CONSUMED
931 #undef PROCESS
932 #undef IEEE80211_FC0_QOSDATA
933 }
934 
935 /*
936  * Process a BAR ctl frame.  Dispatch all frames up to
937  * the sequence number of the frame.  If this frame is
938  * out of range it's discarded.
939  */
940 void
941 ieee80211_recv_bar(struct ieee80211_node *ni, struct mbuf *m0)
942 {
943 	struct ieee80211vap *vap = ni->ni_vap;
944 	struct ieee80211_frame_bar *wh;
945 	struct ieee80211_rx_ampdu *rap;
946 	ieee80211_seq rxseq;
947 	int tid, off;
948 
949 	if (!ieee80211_recv_bar_ena) {
950 #if 0
951 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_11N,
952 		    ni->ni_macaddr, "BAR", "%s", "processing disabled");
953 #endif
954 		vap->iv_stats.is_ampdu_bar_bad++;
955 		return;
956 	}
957 	wh = mtod(m0, struct ieee80211_frame_bar *);
958 	/* XXX check basic BAR */
959 	tid = MS(le16toh(wh->i_ctl), IEEE80211_BAR_TID);
960 	rap = &ni->ni_rx_ampdu[tid];
961 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
962 		/*
963 		 * No ADDBA request yet, don't touch.
964 		 */
965 		IEEE80211_DISCARD_MAC(vap,
966 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
967 		    ni->ni_macaddr, "BAR", "no BA stream, tid %u", tid);
968 		vap->iv_stats.is_ampdu_bar_bad++;
969 		return;
970 	}
971 	vap->iv_stats.is_ampdu_bar_rx++;
972 	rxseq = le16toh(wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
973 	if (rxseq == rap->rxa_start)
974 		return;
975 	/* calculate offset in BA window */
976 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
977 	if (off < IEEE80211_SEQ_BA_RANGE) {
978 		/*
979 		 * Flush the reorder q up to rxseq and move the window.
980 		 * Sec 9.10.7.6.3 a) (p.138)
981 		 */
982 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
983 		    "BAR moves BA win <%u:%u> (%u frames) rxseq %u tid %u",
984 		    rap->rxa_start,
985 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
986 		    rap->rxa_qframes, rxseq, tid);
987 		vap->iv_stats.is_ampdu_bar_move++;
988 
989 		ampdu_rx_flush_upto(ni, rap, rxseq);
990 		if (off >= rap->rxa_wnd) {
991 			/*
992 			 * BAR specifies a window start to the right of BA
993 			 * window; we must move it explicitly since
994 			 * ampdu_rx_flush_upto will not.
995 			 */
996 			rap->rxa_start = rxseq;
997 		}
998 	} else {
999 		/*
1000 		 * Out of range; toss.
1001 		 * Sec 9.10.7.6.3 b) (p.138)
1002 		 */
1003 		IEEE80211_DISCARD_MAC(vap,
1004 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
1005 		    "BAR", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
1006 		    rap->rxa_start,
1007 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1008 		    rap->rxa_qframes, rxseq, tid,
1009 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
1010 		vap->iv_stats.is_ampdu_bar_oow++;
1011 		IEEE80211_NODE_STAT(ni, rx_drop);
1012 	}
1013 }
1014 
1015 /*
1016  * Setup HT-specific state in a node.  Called only
1017  * when HT use is negotiated so we don't do extra
1018  * work for temporary and/or legacy sta's.
1019  */
1020 void
1021 ieee80211_ht_node_init(struct ieee80211_node *ni)
1022 {
1023 	struct ieee80211_tx_ampdu *tap;
1024 	int tid;
1025 
1026 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1027 	    ni,
1028 	    "%s: called",
1029 	    __func__);
1030 
1031 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1032 		/*
1033 		 * Clean AMPDU state on re-associate.  This handles the case
1034 		 * where a station leaves w/o notifying us and then returns
1035 		 * before node is reaped for inactivity.
1036 		 */
1037 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1038 		    ni,
1039 		    "%s: calling cleanup",
1040 		    __func__);
1041 		ieee80211_ht_node_cleanup(ni);
1042 	}
1043 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1044 		tap = &ni->ni_tx_ampdu[tid];
1045 		tap->txa_tid = tid;
1046 		tap->txa_ni = ni;
1047 		tap->txa_lastsample = ticks;
1048 		/* NB: further initialization deferred */
1049 	}
1050 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1051 }
1052 
1053 /*
1054  * Cleanup HT-specific state in a node.  Called only
1055  * when HT use has been marked.
1056  */
1057 void
1058 ieee80211_ht_node_cleanup(struct ieee80211_node *ni)
1059 {
1060 	struct ieee80211com *ic = ni->ni_ic;
1061 	int i;
1062 
1063 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1064 	    ni,
1065 	    "%s: called",
1066 	    __func__);
1067 
1068 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT node"));
1069 
1070 	/* XXX optimize this */
1071 	for (i = 0; i < WME_NUM_TID; i++) {
1072 		struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[i];
1073 		if (tap->txa_flags & IEEE80211_AGGR_SETUP)
1074 			ampdu_tx_stop(tap);
1075 	}
1076 	for (i = 0; i < WME_NUM_TID; i++)
1077 		ic->ic_ampdu_rx_stop(ni, &ni->ni_rx_ampdu[i]);
1078 
1079 	ni->ni_htcap = 0;
1080 	ni->ni_flags &= ~IEEE80211_NODE_HT_ALL;
1081 }
1082 
1083 /*
1084  * Age out HT resources for a station.
1085  */
1086 void
1087 ieee80211_ht_node_age(struct ieee80211_node *ni)
1088 {
1089 #ifdef IEEE80211_AMPDU_AGE
1090 	struct ieee80211vap *vap = ni->ni_vap;
1091 	uint8_t tid;
1092 #endif
1093 
1094 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
1095 
1096 #ifdef IEEE80211_AMPDU_AGE
1097 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1098 		struct ieee80211_rx_ampdu *rap;
1099 
1100 		rap = &ni->ni_rx_ampdu[tid];
1101 		if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0)
1102 			continue;
1103 		if (rap->rxa_qframes == 0)
1104 			continue;
1105 		/*
1106 		 * Check for frames sitting too long in the reorder queue.
1107 		 * See above for more details on what's happening here.
1108 		 */
1109 		/* XXX honor batimeout? */
1110 		if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
1111 			/*
1112 			 * Too long since we received the first
1113 			 * frame; flush the reorder buffer.
1114 			 */
1115 			vap->iv_stats.is_ampdu_rx_age += rap->rxa_qframes;
1116 			ampdu_rx_flush(ni, rap);
1117 		}
1118 	}
1119 #endif /* IEEE80211_AMPDU_AGE */
1120 }
1121 
1122 static struct ieee80211_channel *
1123 findhtchan(struct ieee80211com *ic, struct ieee80211_channel *c, int htflags)
1124 {
1125 	return ieee80211_find_channel(ic, c->ic_freq,
1126 	    (c->ic_flags &~ IEEE80211_CHAN_HT) | htflags);
1127 }
1128 
1129 /*
1130  * Adjust a channel to be HT/non-HT according to the vap's configuration.
1131  */
1132 struct ieee80211_channel *
1133 ieee80211_ht_adjust_channel(struct ieee80211com *ic,
1134 	struct ieee80211_channel *chan, int flags)
1135 {
1136 	struct ieee80211_channel *c;
1137 
1138 	if (flags & IEEE80211_FHT_HT) {
1139 		/* promote to HT if possible */
1140 		if (flags & IEEE80211_FHT_USEHT40) {
1141 			if (!IEEE80211_IS_CHAN_HT40(chan)) {
1142 				/* NB: arbitrarily pick ht40+ over ht40- */
1143 				c = findhtchan(ic, chan, IEEE80211_CHAN_HT40U);
1144 				if (c == NULL)
1145 					c = findhtchan(ic, chan,
1146 						IEEE80211_CHAN_HT40D);
1147 				if (c == NULL)
1148 					c = findhtchan(ic, chan,
1149 						IEEE80211_CHAN_HT20);
1150 				if (c != NULL)
1151 					chan = c;
1152 			}
1153 		} else if (!IEEE80211_IS_CHAN_HT20(chan)) {
1154 			c = findhtchan(ic, chan, IEEE80211_CHAN_HT20);
1155 			if (c != NULL)
1156 				chan = c;
1157 		}
1158 	} else if (IEEE80211_IS_CHAN_HT(chan)) {
1159 		/* demote to legacy, HT use is disabled */
1160 		c = ieee80211_find_channel(ic, chan->ic_freq,
1161 		    chan->ic_flags &~ IEEE80211_CHAN_HT);
1162 		if (c != NULL)
1163 			chan = c;
1164 	}
1165 	return chan;
1166 }
1167 
1168 /*
1169  * Setup HT-specific state for a legacy WDS peer.
1170  */
1171 void
1172 ieee80211_ht_wds_init(struct ieee80211_node *ni)
1173 {
1174 	struct ieee80211vap *vap = ni->ni_vap;
1175 	struct ieee80211_tx_ampdu *tap;
1176 	int tid;
1177 
1178 	KASSERT(vap->iv_flags_ht & IEEE80211_FHT_HT, ("no HT requested"));
1179 
1180 	/* XXX check scan cache in case peer has an ap and we have info */
1181 	/*
1182 	 * If setup with a legacy channel; locate an HT channel.
1183 	 * Otherwise if the inherited channel (from a companion
1184 	 * AP) is suitable use it so we use the same location
1185 	 * for the extension channel).
1186 	 */
1187 	ni->ni_chan = ieee80211_ht_adjust_channel(ni->ni_ic,
1188 	    ni->ni_chan, ieee80211_htchanflags(ni->ni_chan));
1189 
1190 	ni->ni_htcap = 0;
1191 	if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20)
1192 		ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI20;
1193 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan)) {
1194 		ni->ni_htcap |= IEEE80211_HTCAP_CHWIDTH40;
1195 		ni->ni_chw = 40;
1196 		if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
1197 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_ABOVE;
1198 		else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
1199 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_BELOW;
1200 		if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40)
1201 			ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI40;
1202 	} else {
1203 		ni->ni_chw = 20;
1204 		ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_NONE;
1205 	}
1206 	ni->ni_htctlchan = ni->ni_chan->ic_ieee;
1207 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
1208 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1209 	/* XXX does it make sense to enable SMPS? */
1210 
1211 	ni->ni_htopmode = 0;		/* XXX need protection state */
1212 	ni->ni_htstbc = 0;		/* XXX need info */
1213 
1214 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1215 		tap = &ni->ni_tx_ampdu[tid];
1216 		tap->txa_tid = tid;
1217 		tap->txa_lastsample = ticks;
1218 	}
1219 	/* NB: AMPDU tx/rx governed by IEEE80211_FHT_AMPDU_{TX,RX} */
1220 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1221 }
1222 
1223 /*
1224  * Notify hostap vaps of a change in the HTINFO ie.
1225  */
1226 static void
1227 htinfo_notify(struct ieee80211com *ic)
1228 {
1229 	struct ieee80211vap *vap;
1230 	int first = 1;
1231 
1232 	IEEE80211_LOCK_ASSERT(ic);
1233 
1234 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
1235 		if (vap->iv_opmode != IEEE80211_M_HOSTAP)
1236 			continue;
1237 		if (vap->iv_state != IEEE80211_S_RUN ||
1238 		    !IEEE80211_IS_CHAN_HT(vap->iv_bss->ni_chan))
1239 			continue;
1240 		if (first) {
1241 			IEEE80211_NOTE(vap,
1242 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1243 			    vap->iv_bss,
1244 			    "HT bss occupancy change: %d sta, %d ht, "
1245 			    "%d ht40%s, HT protmode now 0x%x"
1246 			    , ic->ic_sta_assoc
1247 			    , ic->ic_ht_sta_assoc
1248 			    , ic->ic_ht40_sta_assoc
1249 			    , (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) ?
1250 				 ", non-HT sta present" : ""
1251 			    , ic->ic_curhtprotmode);
1252 			first = 0;
1253 		}
1254 		ieee80211_beacon_notify(vap, IEEE80211_BEACON_HTINFO);
1255 	}
1256 }
1257 
1258 /*
1259  * Calculate HT protection mode from current
1260  * state and handle updates.
1261  */
1262 static void
1263 htinfo_update(struct ieee80211com *ic)
1264 {
1265 	uint8_t protmode;
1266 
1267 	if (ic->ic_sta_assoc != ic->ic_ht_sta_assoc) {
1268 		protmode = IEEE80211_HTINFO_OPMODE_MIXED
1269 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1270 	} else if (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) {
1271 		protmode = IEEE80211_HTINFO_OPMODE_PROTOPT
1272 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1273 	} else if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
1274 	    IEEE80211_IS_CHAN_HT40(ic->ic_bsschan) &&
1275 	    ic->ic_sta_assoc != ic->ic_ht40_sta_assoc) {
1276 		protmode = IEEE80211_HTINFO_OPMODE_HT20PR;
1277 	} else {
1278 		protmode = IEEE80211_HTINFO_OPMODE_PURE;
1279 	}
1280 	if (protmode != ic->ic_curhtprotmode) {
1281 		ic->ic_curhtprotmode = protmode;
1282 		htinfo_notify(ic);
1283 	}
1284 }
1285 
1286 /*
1287  * Handle an HT station joining a BSS.
1288  */
1289 void
1290 ieee80211_ht_node_join(struct ieee80211_node *ni)
1291 {
1292 	struct ieee80211com *ic = ni->ni_ic;
1293 
1294 	IEEE80211_LOCK_ASSERT(ic);
1295 
1296 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1297 		ic->ic_ht_sta_assoc++;
1298 		if (ni->ni_chw == 40)
1299 			ic->ic_ht40_sta_assoc++;
1300 	}
1301 	htinfo_update(ic);
1302 }
1303 
1304 /*
1305  * Handle an HT station leaving a BSS.
1306  */
1307 void
1308 ieee80211_ht_node_leave(struct ieee80211_node *ni)
1309 {
1310 	struct ieee80211com *ic = ni->ni_ic;
1311 
1312 	IEEE80211_LOCK_ASSERT(ic);
1313 
1314 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1315 		ic->ic_ht_sta_assoc--;
1316 		if (ni->ni_chw == 40)
1317 			ic->ic_ht40_sta_assoc--;
1318 	}
1319 	htinfo_update(ic);
1320 }
1321 
1322 /*
1323  * Public version of htinfo_update; used for processing
1324  * beacon frames from overlapping bss.
1325  *
1326  * Caller can specify either IEEE80211_HTINFO_OPMODE_MIXED
1327  * (on receipt of a beacon that advertises MIXED) or
1328  * IEEE80211_HTINFO_OPMODE_PROTOPT (on receipt of a beacon
1329  * from an overlapping legacy bss).  We treat MIXED with
1330  * a higher precedence than PROTOPT (i.e. we will not change
1331  * change PROTOPT -> MIXED; only MIXED -> PROTOPT).  This
1332  * corresponds to how we handle things in htinfo_update.
1333  */
1334 void
1335 ieee80211_htprot_update(struct ieee80211com *ic, int protmode)
1336 {
1337 #define	OPMODE(x)	SM(x, IEEE80211_HTINFO_OPMODE)
1338 	IEEE80211_LOCK(ic);
1339 
1340 	/* track non-HT station presence */
1341 	KASSERT(protmode & IEEE80211_HTINFO_NONHT_PRESENT,
1342 	    ("protmode 0x%x", protmode));
1343 	ic->ic_flags_ht |= IEEE80211_FHT_NONHT_PR;
1344 	ic->ic_lastnonht = ticks;
1345 
1346 	if (protmode != ic->ic_curhtprotmode &&
1347 	    (OPMODE(ic->ic_curhtprotmode) != IEEE80211_HTINFO_OPMODE_MIXED ||
1348 	     OPMODE(protmode) == IEEE80211_HTINFO_OPMODE_PROTOPT)) {
1349 		/* push beacon update */
1350 		ic->ic_curhtprotmode = protmode;
1351 		htinfo_notify(ic);
1352 	}
1353 	IEEE80211_UNLOCK(ic);
1354 #undef OPMODE
1355 }
1356 
1357 /*
1358  * Time out presence of an overlapping bss with non-HT
1359  * stations.  When operating in hostap mode we listen for
1360  * beacons from other stations and if we identify a non-HT
1361  * station is present we update the opmode field of the
1362  * HTINFO ie.  To identify when all non-HT stations are
1363  * gone we time out this condition.
1364  */
1365 void
1366 ieee80211_ht_timeout(struct ieee80211com *ic)
1367 {
1368 	IEEE80211_LOCK_ASSERT(ic);
1369 
1370 	if ((ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) &&
1371 	    time_after(ticks, ic->ic_lastnonht + IEEE80211_NONHT_PRESENT_AGE)) {
1372 #if 0
1373 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1374 		    "%s", "time out non-HT STA present on channel");
1375 #endif
1376 		ic->ic_flags_ht &= ~IEEE80211_FHT_NONHT_PR;
1377 		htinfo_update(ic);
1378 	}
1379 }
1380 
1381 /* unalligned little endian access */
1382 #define LE_READ_2(p)					\
1383 	((uint16_t)					\
1384 	 ((((const uint8_t *)(p))[0]      ) |		\
1385 	  (((const uint8_t *)(p))[1] <<  8)))
1386 
1387 /*
1388  * Process an 802.11n HT capabilities ie.
1389  */
1390 void
1391 ieee80211_parse_htcap(struct ieee80211_node *ni, const uint8_t *ie)
1392 {
1393 	if (ie[0] == IEEE80211_ELEMID_VENDOR) {
1394 		/*
1395 		 * Station used Vendor OUI ie to associate;
1396 		 * mark the node so when we respond we'll use
1397 		 * the Vendor OUI's and not the standard ie's.
1398 		 */
1399 		ni->ni_flags |= IEEE80211_NODE_HTCOMPAT;
1400 		ie += 4;
1401 	} else
1402 		ni->ni_flags &= ~IEEE80211_NODE_HTCOMPAT;
1403 
1404 	ni->ni_htcap = LE_READ_2(ie +
1405 		__offsetof(struct ieee80211_ie_htcap, hc_cap));
1406 	ni->ni_htparam = ie[__offsetof(struct ieee80211_ie_htcap, hc_param)];
1407 }
1408 
1409 static void
1410 htinfo_parse(struct ieee80211_node *ni,
1411 	const struct ieee80211_ie_htinfo *htinfo)
1412 {
1413 	uint16_t w;
1414 
1415 	ni->ni_htctlchan = htinfo->hi_ctrlchannel;
1416 	ni->ni_ht2ndchan = SM(htinfo->hi_byte1, IEEE80211_HTINFO_2NDCHAN);
1417 	w = LE_READ_2(&htinfo->hi_byte2);
1418 	ni->ni_htopmode = SM(w, IEEE80211_HTINFO_OPMODE);
1419 	w = LE_READ_2(&htinfo->hi_byte45);
1420 	ni->ni_htstbc = SM(w, IEEE80211_HTINFO_BASIC_STBCMCS);
1421 }
1422 
1423 /*
1424  * Parse an 802.11n HT info ie and save useful information
1425  * to the node state.  Note this does not effect any state
1426  * changes such as for channel width change.
1427  */
1428 void
1429 ieee80211_parse_htinfo(struct ieee80211_node *ni, const uint8_t *ie)
1430 {
1431 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1432 		ie += 4;
1433 	htinfo_parse(ni, (const struct ieee80211_ie_htinfo *) ie);
1434 }
1435 
1436 /*
1437  * Handle 11n channel switch.  Use the received HT ie's to
1438  * identify the right channel to use.  If we cannot locate it
1439  * in the channel table then fallback to legacy operation.
1440  * Note that we use this information to identify the node's
1441  * channel only; the caller is responsible for insuring any
1442  * required channel change is done (e.g. in sta mode when
1443  * parsing the contents of a beacon frame).
1444  */
1445 static int
1446 htinfo_update_chw(struct ieee80211_node *ni, int htflags)
1447 {
1448 	struct ieee80211com *ic = ni->ni_ic;
1449 	struct ieee80211_channel *c;
1450 	int chanflags;
1451 	int ret = 0;
1452 
1453 	chanflags = (ni->ni_chan->ic_flags &~ IEEE80211_CHAN_HT) | htflags;
1454 	if (chanflags != ni->ni_chan->ic_flags) {
1455 		/* XXX not right for ht40- */
1456 		c = ieee80211_find_channel(ic, ni->ni_chan->ic_freq, chanflags);
1457 		if (c == NULL && (htflags & IEEE80211_CHAN_HT40)) {
1458 			/*
1459 			 * No HT40 channel entry in our table; fall back
1460 			 * to HT20 operation.  This should not happen.
1461 			 */
1462 			c = findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT20);
1463 #if 0
1464 			IEEE80211_NOTE(ni->ni_vap,
1465 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1466 			    "no HT40 channel (freq %u), falling back to HT20",
1467 			    ni->ni_chan->ic_freq);
1468 #endif
1469 			/* XXX stat */
1470 		}
1471 		if (c != NULL && c != ni->ni_chan) {
1472 			IEEE80211_NOTE(ni->ni_vap,
1473 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1474 			    "switch station to HT%d channel %u/0x%x",
1475 			    IEEE80211_IS_CHAN_HT40(c) ? 40 : 20,
1476 			    c->ic_freq, c->ic_flags);
1477 			ni->ni_chan = c;
1478 			ret = 1;
1479 		}
1480 		/* NB: caller responsible for forcing any channel change */
1481 	}
1482 	/* update node's tx channel width */
1483 	ni->ni_chw = IEEE80211_IS_CHAN_HT40(ni->ni_chan)? 40 : 20;
1484 	return (ret);
1485 }
1486 
1487 /*
1488  * Update 11n MIMO PS state according to received htcap.
1489  */
1490 static __inline int
1491 htcap_update_mimo_ps(struct ieee80211_node *ni)
1492 {
1493 	uint16_t oflags = ni->ni_flags;
1494 
1495 	switch (ni->ni_htcap & IEEE80211_HTCAP_SMPS) {
1496 	case IEEE80211_HTCAP_SMPS_DYNAMIC:
1497 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1498 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1499 		break;
1500 	case IEEE80211_HTCAP_SMPS_ENA:
1501 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1502 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1503 		break;
1504 	case IEEE80211_HTCAP_SMPS_OFF:
1505 	default:		/* disable on rx of reserved value */
1506 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1507 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1508 		break;
1509 	}
1510 	return (oflags ^ ni->ni_flags);
1511 }
1512 
1513 /*
1514  * Update short GI state according to received htcap
1515  * and local settings.
1516  */
1517 static __inline void
1518 htcap_update_shortgi(struct ieee80211_node *ni)
1519 {
1520 	struct ieee80211vap *vap = ni->ni_vap;
1521 
1522 	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
1523 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
1524 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20))
1525 		ni->ni_flags |= IEEE80211_NODE_SGI20;
1526 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
1527 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40))
1528 		ni->ni_flags |= IEEE80211_NODE_SGI40;
1529 }
1530 
1531 /*
1532  * Parse and update HT-related state extracted from
1533  * the HT cap and info ie's.
1534  */
1535 int
1536 ieee80211_ht_updateparams(struct ieee80211_node *ni,
1537 	const uint8_t *htcapie, const uint8_t *htinfoie)
1538 {
1539 	struct ieee80211vap *vap = ni->ni_vap;
1540 	const struct ieee80211_ie_htinfo *htinfo;
1541 	int htflags;
1542 	int ret = 0;
1543 
1544 	ieee80211_parse_htcap(ni, htcapie);
1545 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1546 		htcap_update_mimo_ps(ni);
1547 	htcap_update_shortgi(ni);
1548 
1549 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
1550 		htinfoie += 4;
1551 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1552 	htinfo_parse(ni, htinfo);
1553 
1554 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1555 	    IEEE80211_CHAN_HT20 : 0;
1556 	/* NB: honor operating mode constraint */
1557 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_TXWIDTH_2040) &&
1558 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1559 		if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_ABOVE)
1560 			htflags = IEEE80211_CHAN_HT40U;
1561 		else if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_BELOW)
1562 			htflags = IEEE80211_CHAN_HT40D;
1563 	}
1564 	if (htinfo_update_chw(ni, htflags))
1565 		ret = 1;
1566 
1567 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_RIFSMODE_PERM) &&
1568 	    (vap->iv_flags_ht & IEEE80211_FHT_RIFS))
1569 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1570 	else
1571 		ni->ni_flags &= ~IEEE80211_NODE_RIFS;
1572 
1573 	return (ret);
1574 }
1575 
1576 /*
1577  * Parse and update HT-related state extracted from the HT cap ie
1578  * for a station joining an HT BSS.
1579  */
1580 void
1581 ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
1582 {
1583 	struct ieee80211vap *vap = ni->ni_vap;
1584 	int htflags;
1585 
1586 	ieee80211_parse_htcap(ni, htcapie);
1587 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1588 		htcap_update_mimo_ps(ni);
1589 	htcap_update_shortgi(ni);
1590 
1591 	/* NB: honor operating mode constraint */
1592 	/* XXX 40 MHz intolerant */
1593 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1594 	    IEEE80211_CHAN_HT20 : 0;
1595 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) &&
1596 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1597 		if (IEEE80211_IS_CHAN_HT40U(vap->iv_bss->ni_chan))
1598 			htflags = IEEE80211_CHAN_HT40U;
1599 		else if (IEEE80211_IS_CHAN_HT40D(vap->iv_bss->ni_chan))
1600 			htflags = IEEE80211_CHAN_HT40D;
1601 	}
1602 	(void) htinfo_update_chw(ni, htflags);
1603 }
1604 
1605 /*
1606  * Install received HT rate set by parsing the HT cap ie.
1607  */
1608 int
1609 ieee80211_setup_htrates(struct ieee80211_node *ni, const uint8_t *ie, int flags)
1610 {
1611 	struct ieee80211com *ic = ni->ni_ic;
1612 	struct ieee80211vap *vap = ni->ni_vap;
1613 	const struct ieee80211_ie_htcap *htcap;
1614 	struct ieee80211_htrateset *rs;
1615 	int i, maxequalmcs, maxunequalmcs;
1616 
1617 	maxequalmcs = ic->ic_txstream * 8 - 1;
1618 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
1619 		if (ic->ic_txstream >= 2)
1620 			maxunequalmcs = 38;
1621 		if (ic->ic_txstream >= 3)
1622 			maxunequalmcs = 52;
1623 		if (ic->ic_txstream >= 4)
1624 			maxunequalmcs = 76;
1625 	} else
1626 		maxunequalmcs = 0;
1627 
1628 	rs = &ni->ni_htrates;
1629 	memset(rs, 0, sizeof(*rs));
1630 	if (ie != NULL) {
1631 		if (ie[0] == IEEE80211_ELEMID_VENDOR)
1632 			ie += 4;
1633 		htcap = (const struct ieee80211_ie_htcap *) ie;
1634 		for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1635 			if (isclr(htcap->hc_mcsset, i))
1636 				continue;
1637 			if (rs->rs_nrates == IEEE80211_HTRATE_MAXSIZE) {
1638 				IEEE80211_NOTE(vap,
1639 				    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1640 				    "WARNING, HT rate set too large; only "
1641 				    "using %u rates", IEEE80211_HTRATE_MAXSIZE);
1642 				vap->iv_stats.is_rx_rstoobig++;
1643 				break;
1644 			}
1645 			if (i <= 31 && i > maxequalmcs)
1646 				continue;
1647 			if (i == 32 &&
1648 			    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32) == 0)
1649 				continue;
1650 			if (i > 32 && i > maxunequalmcs)
1651 				continue;
1652 			rs->rs_rates[rs->rs_nrates++] = i;
1653 		}
1654 	}
1655 	return ieee80211_fix_rate(ni, (struct ieee80211_rateset *) rs, flags);
1656 }
1657 
1658 /*
1659  * Mark rates in a node's HT rate set as basic according
1660  * to the information in the supplied HT info ie.
1661  */
1662 void
1663 ieee80211_setup_basic_htrates(struct ieee80211_node *ni, const uint8_t *ie)
1664 {
1665 	const struct ieee80211_ie_htinfo *htinfo;
1666 	struct ieee80211_htrateset *rs;
1667 	int i, j;
1668 
1669 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1670 		ie += 4;
1671 	htinfo = (const struct ieee80211_ie_htinfo *) ie;
1672 	rs = &ni->ni_htrates;
1673 	if (rs->rs_nrates == 0) {
1674 		IEEE80211_NOTE(ni->ni_vap,
1675 		    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1676 		    "%s", "WARNING, empty HT rate set");
1677 		return;
1678 	}
1679 	for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1680 		if (isclr(htinfo->hi_basicmcsset, i))
1681 			continue;
1682 		for (j = 0; j < rs->rs_nrates; j++)
1683 			if ((rs->rs_rates[j] & IEEE80211_RATE_VAL) == i)
1684 				rs->rs_rates[j] |= IEEE80211_RATE_BASIC;
1685 	}
1686 }
1687 
1688 static void
1689 ampdu_tx_setup(struct ieee80211_tx_ampdu *tap)
1690 {
1691 	callout_init(&tap->txa_timer, 1);
1692 	tap->txa_flags |= IEEE80211_AGGR_SETUP;
1693 	tap->txa_lastsample = ticks;
1694 }
1695 
1696 static void
1697 ampdu_tx_stop(struct ieee80211_tx_ampdu *tap)
1698 {
1699 	struct ieee80211_node *ni = tap->txa_ni;
1700 	struct ieee80211com *ic = ni->ni_ic;
1701 
1702 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
1703 	    tap->txa_ni,
1704 	    "%s: called",
1705 	    __func__);
1706 
1707 	KASSERT(tap->txa_flags & IEEE80211_AGGR_SETUP,
1708 	    ("txa_flags 0x%x tid %d ac %d", tap->txa_flags, tap->txa_tid,
1709 	    TID_TO_WME_AC(tap->txa_tid)));
1710 
1711 	/*
1712 	 * Stop BA stream if setup so driver has a chance
1713 	 * to reclaim any resources it might have allocated.
1714 	 */
1715 	ic->ic_addba_stop(ni, tap);
1716 	/*
1717 	 * Stop any pending BAR transmit.
1718 	 */
1719 	bar_stop_timer(tap);
1720 
1721 	/*
1722 	 * Reset packet estimate.
1723 	 */
1724 	tap->txa_lastsample = ticks;
1725 	tap->txa_avgpps = 0;
1726 
1727 	/* NB: clearing NAK means we may re-send ADDBA */
1728 	tap->txa_flags &= ~(IEEE80211_AGGR_SETUP | IEEE80211_AGGR_NAK);
1729 }
1730 
1731 /*
1732  * ADDBA response timeout.
1733  *
1734  * If software aggregation and per-TID queue management was done here,
1735  * that queue would be unpaused after the ADDBA timeout occurs.
1736  */
1737 static void
1738 addba_timeout(void *arg)
1739 {
1740 	struct ieee80211_tx_ampdu *tap = arg;
1741 	struct ieee80211_node *ni = tap->txa_ni;
1742 	struct ieee80211com *ic = ni->ni_ic;
1743 
1744 	/* XXX ? */
1745 	tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1746 	tap->txa_attempts++;
1747 	ic->ic_addba_response_timeout(ni, tap);
1748 }
1749 
1750 static void
1751 addba_start_timeout(struct ieee80211_tx_ampdu *tap)
1752 {
1753 	/* XXX use CALLOUT_PENDING instead? */
1754 	callout_reset(&tap->txa_timer, ieee80211_addba_timeout,
1755 	    addba_timeout, tap);
1756 	tap->txa_flags |= IEEE80211_AGGR_XCHGPEND;
1757 	tap->txa_nextrequest = ticks + ieee80211_addba_timeout;
1758 }
1759 
1760 static void
1761 addba_stop_timeout(struct ieee80211_tx_ampdu *tap)
1762 {
1763 	/* XXX use CALLOUT_PENDING instead? */
1764 	if (tap->txa_flags & IEEE80211_AGGR_XCHGPEND) {
1765 		callout_stop(&tap->txa_timer);
1766 		tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1767 	}
1768 }
1769 
1770 static void
1771 null_addba_response_timeout(struct ieee80211_node *ni,
1772     struct ieee80211_tx_ampdu *tap)
1773 {
1774 }
1775 
1776 /*
1777  * Default method for requesting A-MPDU tx aggregation.
1778  * We setup the specified state block and start a timer
1779  * to wait for an ADDBA response frame.
1780  */
1781 static int
1782 ieee80211_addba_request(struct ieee80211_node *ni,
1783 	struct ieee80211_tx_ampdu *tap,
1784 	int dialogtoken, int baparamset, int batimeout)
1785 {
1786 	int bufsiz;
1787 
1788 	/* XXX locking */
1789 	tap->txa_token = dialogtoken;
1790 	tap->txa_flags |= IEEE80211_AGGR_IMMEDIATE;
1791 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1792 	tap->txa_wnd = (bufsiz == 0) ?
1793 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1794 	addba_start_timeout(tap);
1795 	return 1;
1796 }
1797 
1798 /*
1799  * Default method for processing an A-MPDU tx aggregation
1800  * response.  We shutdown any pending timer and update the
1801  * state block according to the reply.
1802  */
1803 static int
1804 ieee80211_addba_response(struct ieee80211_node *ni,
1805 	struct ieee80211_tx_ampdu *tap,
1806 	int status, int baparamset, int batimeout)
1807 {
1808 	int bufsiz, tid;
1809 
1810 	/* XXX locking */
1811 	addba_stop_timeout(tap);
1812 	if (status == IEEE80211_STATUS_SUCCESS) {
1813 		bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1814 		/* XXX override our request? */
1815 		tap->txa_wnd = (bufsiz == 0) ?
1816 		    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1817 		/* XXX AC/TID */
1818 		tid = MS(baparamset, IEEE80211_BAPS_TID);
1819 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
1820 		tap->txa_attempts = 0;
1821 	} else {
1822 		/* mark tid so we don't try again */
1823 		tap->txa_flags |= IEEE80211_AGGR_NAK;
1824 	}
1825 	return 1;
1826 }
1827 
1828 /*
1829  * Default method for stopping A-MPDU tx aggregation.
1830  * Any timer is cleared and we drain any pending frames.
1831  */
1832 static void
1833 ieee80211_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
1834 {
1835 	/* XXX locking */
1836 	addba_stop_timeout(tap);
1837 	if (tap->txa_flags & IEEE80211_AGGR_RUNNING) {
1838 		/* XXX clear aggregation queue */
1839 		tap->txa_flags &= ~IEEE80211_AGGR_RUNNING;
1840 	}
1841 	tap->txa_attempts = 0;
1842 }
1843 
1844 /*
1845  * Process a received action frame using the default aggregation
1846  * policy.  We intercept ADDBA-related frames and use them to
1847  * update our aggregation state.  All other frames are passed up
1848  * for processing by ieee80211_recv_action.
1849  */
1850 static int
1851 ht_recv_action_ba_addba_request(struct ieee80211_node *ni,
1852 	const struct ieee80211_frame *wh,
1853 	const uint8_t *frm, const uint8_t *efrm)
1854 {
1855 	struct ieee80211com *ic = ni->ni_ic;
1856 	struct ieee80211vap *vap = ni->ni_vap;
1857 	struct ieee80211_rx_ampdu *rap;
1858 	uint8_t dialogtoken;
1859 	uint16_t baparamset, batimeout, baseqctl;
1860 	uint16_t args[5];
1861 	int tid;
1862 
1863 	dialogtoken = frm[2];
1864 	baparamset = LE_READ_2(frm+3);
1865 	batimeout = LE_READ_2(frm+5);
1866 	baseqctl = LE_READ_2(frm+7);
1867 
1868 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1869 
1870 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1871 	    "recv ADDBA request: dialogtoken %u baparamset 0x%x "
1872 	    "(tid %d bufsiz %d) batimeout %d baseqctl %d:%d",
1873 	    dialogtoken, baparamset,
1874 	    tid, MS(baparamset, IEEE80211_BAPS_BUFSIZ),
1875 	    batimeout,
1876 	    MS(baseqctl, IEEE80211_BASEQ_START),
1877 	    MS(baseqctl, IEEE80211_BASEQ_FRAG));
1878 
1879 	rap = &ni->ni_rx_ampdu[tid];
1880 
1881 	/* Send ADDBA response */
1882 	args[0] = dialogtoken;
1883 	/*
1884 	 * NB: We ack only if the sta associated with HT and
1885 	 * the ap is configured to do AMPDU rx (the latter
1886 	 * violates the 11n spec and is mostly for testing).
1887 	 */
1888 	if ((ni->ni_flags & IEEE80211_NODE_AMPDU_RX) &&
1889 	    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_RX)) {
1890 		/* XXX handle ampdu_rx_start failure */
1891 		ic->ic_ampdu_rx_start(ni, rap,
1892 		    baparamset, batimeout, baseqctl);
1893 
1894 		args[1] = IEEE80211_STATUS_SUCCESS;
1895 	} else {
1896 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1897 		    ni, "reject ADDBA request: %s",
1898 		    ni->ni_flags & IEEE80211_NODE_AMPDU_RX ?
1899 		       "administratively disabled" :
1900 		       "not negotiated for station");
1901 		vap->iv_stats.is_addba_reject++;
1902 		args[1] = IEEE80211_STATUS_UNSPECIFIED;
1903 	}
1904 	/* XXX honor rap flags? */
1905 	args[2] = IEEE80211_BAPS_POLICY_IMMEDIATE
1906 		| SM(tid, IEEE80211_BAPS_TID)
1907 		| SM(rap->rxa_wnd, IEEE80211_BAPS_BUFSIZ)
1908 		;
1909 	args[3] = 0;
1910 	args[4] = 0;
1911 	ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1912 		IEEE80211_ACTION_BA_ADDBA_RESPONSE, args);
1913 	return 0;
1914 }
1915 
1916 static int
1917 ht_recv_action_ba_addba_response(struct ieee80211_node *ni,
1918 	const struct ieee80211_frame *wh,
1919 	const uint8_t *frm, const uint8_t *efrm)
1920 {
1921 	struct ieee80211com *ic = ni->ni_ic;
1922 	struct ieee80211vap *vap = ni->ni_vap;
1923 	struct ieee80211_tx_ampdu *tap;
1924 	uint8_t dialogtoken, policy;
1925 	uint16_t baparamset, batimeout, code;
1926 	int tid, bufsiz;
1927 
1928 	dialogtoken = frm[2];
1929 	code = LE_READ_2(frm+3);
1930 	baparamset = LE_READ_2(frm+5);
1931 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1932 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1933 	policy = MS(baparamset, IEEE80211_BAPS_POLICY);
1934 	batimeout = LE_READ_2(frm+7);
1935 
1936 	tap = &ni->ni_tx_ampdu[tid];
1937 	if ((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
1938 		IEEE80211_DISCARD_MAC(vap,
1939 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1940 		    ni->ni_macaddr, "ADDBA response",
1941 		    "no pending ADDBA, tid %d dialogtoken %u "
1942 		    "code %d", tid, dialogtoken, code);
1943 		vap->iv_stats.is_addba_norequest++;
1944 		return 0;
1945 	}
1946 	if (dialogtoken != tap->txa_token) {
1947 		IEEE80211_DISCARD_MAC(vap,
1948 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1949 		    ni->ni_macaddr, "ADDBA response",
1950 		    "dialogtoken mismatch: waiting for %d, "
1951 		    "received %d, tid %d code %d",
1952 		    tap->txa_token, dialogtoken, tid, code);
1953 		vap->iv_stats.is_addba_badtoken++;
1954 		return 0;
1955 	}
1956 	/* NB: assumes IEEE80211_AGGR_IMMEDIATE is 1 */
1957 	if (policy != (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE)) {
1958 		IEEE80211_DISCARD_MAC(vap,
1959 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1960 		    ni->ni_macaddr, "ADDBA response",
1961 		    "policy mismatch: expecting %s, "
1962 		    "received %s, tid %d code %d",
1963 		    tap->txa_flags & IEEE80211_AGGR_IMMEDIATE,
1964 		    policy, tid, code);
1965 		vap->iv_stats.is_addba_badpolicy++;
1966 		return 0;
1967 	}
1968 #if 0
1969 	/* XXX we take MIN in ieee80211_addba_response */
1970 	if (bufsiz > IEEE80211_AGGR_BAWMAX) {
1971 		IEEE80211_DISCARD_MAC(vap,
1972 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1973 		    ni->ni_macaddr, "ADDBA response",
1974 		    "BA window too large: max %d, "
1975 		    "received %d, tid %d code %d",
1976 		    bufsiz, IEEE80211_AGGR_BAWMAX, tid, code);
1977 		vap->iv_stats.is_addba_badbawinsize++;
1978 		return 0;
1979 	}
1980 #endif
1981 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1982 	    "recv ADDBA response: dialogtoken %u code %d "
1983 	    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d",
1984 	    dialogtoken, code, baparamset, tid, bufsiz,
1985 	    batimeout);
1986 	ic->ic_addba_response(ni, tap, code, baparamset, batimeout);
1987 	return 0;
1988 }
1989 
1990 static int
1991 ht_recv_action_ba_delba(struct ieee80211_node *ni,
1992 	const struct ieee80211_frame *wh,
1993 	const uint8_t *frm, const uint8_t *efrm)
1994 {
1995 	struct ieee80211com *ic = ni->ni_ic;
1996 	struct ieee80211_rx_ampdu *rap;
1997 	struct ieee80211_tx_ampdu *tap;
1998 	uint16_t baparamset, code;
1999 	int tid;
2000 
2001 	baparamset = LE_READ_2(frm+2);
2002 	code = LE_READ_2(frm+4);
2003 
2004 	tid = MS(baparamset, IEEE80211_DELBAPS_TID);
2005 
2006 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2007 	    "recv DELBA: baparamset 0x%x (tid %d initiator %d) "
2008 	    "code %d", baparamset, tid,
2009 	    MS(baparamset, IEEE80211_DELBAPS_INIT), code);
2010 
2011 	if ((baparamset & IEEE80211_DELBAPS_INIT) == 0) {
2012 		tap = &ni->ni_tx_ampdu[tid];
2013 		ic->ic_addba_stop(ni, tap);
2014 	} else {
2015 		rap = &ni->ni_rx_ampdu[tid];
2016 		ic->ic_ampdu_rx_stop(ni, rap);
2017 	}
2018 	return 0;
2019 }
2020 
2021 static int
2022 ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
2023 	const struct ieee80211_frame *wh,
2024 	const uint8_t *frm, const uint8_t *efrm)
2025 {
2026 	int chw;
2027 
2028 	chw = (frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040) ? 40 : 20;
2029 
2030 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2031 	    "%s: HT txchwidth, width %d%s",
2032 	    __func__, chw, ni->ni_chw != chw ? "*" : "");
2033 	if (chw != ni->ni_chw) {
2034 		ni->ni_chw = chw;
2035 		/* XXX notify on change */
2036 	}
2037 	return 0;
2038 }
2039 
2040 static int
2041 ht_recv_action_ht_mimopwrsave(struct ieee80211_node *ni,
2042 	const struct ieee80211_frame *wh,
2043 	const uint8_t *frm, const uint8_t *efrm)
2044 {
2045 	const struct ieee80211_action_ht_mimopowersave *mps =
2046 	    (const struct ieee80211_action_ht_mimopowersave *) frm;
2047 
2048 	/* XXX check iv_htcaps */
2049 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_ENA)
2050 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
2051 	else
2052 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
2053 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_MODE)
2054 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
2055 	else
2056 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
2057 	/* XXX notify on change */
2058 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2059 	    "%s: HT MIMO PS (%s%s)", __func__,
2060 	    (ni->ni_flags & IEEE80211_NODE_MIMO_PS) ?  "on" : "off",
2061 	    (ni->ni_flags & IEEE80211_NODE_MIMO_RTS) ?  "+rts" : ""
2062 	);
2063 	return 0;
2064 }
2065 
2066 /*
2067  * Transmit processing.
2068  */
2069 
2070 /*
2071  * Check if A-MPDU should be requested/enabled for a stream.
2072  * We require a traffic rate above a per-AC threshold and we
2073  * also handle backoff from previous failed attempts.
2074  *
2075  * Drivers may override this method to bring in information
2076  * such as link state conditions in making the decision.
2077  */
2078 static int
2079 ieee80211_ampdu_enable(struct ieee80211_node *ni,
2080 	struct ieee80211_tx_ampdu *tap)
2081 {
2082 	struct ieee80211vap *vap = ni->ni_vap;
2083 
2084 	if (tap->txa_avgpps <
2085 	    vap->iv_ampdu_mintraffic[TID_TO_WME_AC(tap->txa_tid)])
2086 		return 0;
2087 	/* XXX check rssi? */
2088 	if (tap->txa_attempts >= ieee80211_addba_maxtries &&
2089 	    ticks < tap->txa_nextrequest) {
2090 		/*
2091 		 * Don't retry too often; txa_nextrequest is set
2092 		 * to the minimum interval we'll retry after
2093 		 * ieee80211_addba_maxtries failed attempts are made.
2094 		 */
2095 		return 0;
2096 	}
2097 	IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
2098 	    "enable AMPDU on tid %d (%s), avgpps %d pkts %d",
2099 	    tap->txa_tid, ieee80211_wme_acnames[TID_TO_WME_AC(tap->txa_tid)],
2100 	    tap->txa_avgpps, tap->txa_pkts);
2101 	return 1;
2102 }
2103 
2104 /*
2105  * Request A-MPDU tx aggregation.  Setup local state and
2106  * issue an ADDBA request.  BA use will only happen after
2107  * the other end replies with ADDBA response.
2108  */
2109 int
2110 ieee80211_ampdu_request(struct ieee80211_node *ni,
2111 	struct ieee80211_tx_ampdu *tap)
2112 {
2113 	struct ieee80211com *ic = ni->ni_ic;
2114 	uint16_t args[5];
2115 	int tid, dialogtoken;
2116 	static int tokens = 0;	/* XXX */
2117 
2118 	/* XXX locking */
2119 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
2120 		/* do deferred setup of state */
2121 		ampdu_tx_setup(tap);
2122 	}
2123 	/* XXX hack for not doing proper locking */
2124 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
2125 
2126 	dialogtoken = (tokens+1) % 63;		/* XXX */
2127 	tid = tap->txa_tid;
2128 	tap->txa_start = ni->ni_txseqs[tid];
2129 
2130 	args[0] = dialogtoken;
2131 	args[1] = 0;	/* NB: status code not used */
2132 	args[2]	= IEEE80211_BAPS_POLICY_IMMEDIATE
2133 		| SM(tid, IEEE80211_BAPS_TID)
2134 		| SM(IEEE80211_AGGR_BAWMAX, IEEE80211_BAPS_BUFSIZ)
2135 		;
2136 	args[3] = 0;	/* batimeout */
2137 	/* NB: do first so there's no race against reply */
2138 	if (!ic->ic_addba_request(ni, tap, dialogtoken, args[2], args[3])) {
2139 		/* unable to setup state, don't make request */
2140 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2141 		    ni, "%s: could not setup BA stream for TID %d AC %d",
2142 		    __func__, tap->txa_tid, TID_TO_WME_AC(tap->txa_tid));
2143 		/* defer next try so we don't slam the driver with requests */
2144 		tap->txa_attempts = ieee80211_addba_maxtries;
2145 		/* NB: check in case driver wants to override */
2146 		if (tap->txa_nextrequest <= ticks)
2147 			tap->txa_nextrequest = ticks + ieee80211_addba_backoff;
2148 		return 0;
2149 	}
2150 	tokens = dialogtoken;			/* allocate token */
2151 	/* NB: after calling ic_addba_request so driver can set txa_start */
2152 	args[4] = SM(tap->txa_start, IEEE80211_BASEQ_START)
2153 		| SM(0, IEEE80211_BASEQ_FRAG)
2154 		;
2155 	return ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2156 		IEEE80211_ACTION_BA_ADDBA_REQUEST, args);
2157 }
2158 
2159 /*
2160  * Terminate an AMPDU tx stream.  State is reclaimed
2161  * and the peer notified with a DelBA Action frame.
2162  */
2163 void
2164 ieee80211_ampdu_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
2165 	int reason)
2166 {
2167 	struct ieee80211com *ic = ni->ni_ic;
2168 	struct ieee80211vap *vap = ni->ni_vap;
2169 	uint16_t args[4];
2170 
2171 	/* XXX locking */
2172 	tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2173 	if (IEEE80211_AMPDU_RUNNING(tap)) {
2174 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2175 		    ni, "%s: stop BA stream for TID %d (reason %d)",
2176 		    __func__, tap->txa_tid, reason);
2177 		vap->iv_stats.is_ampdu_stop++;
2178 
2179 		ic->ic_addba_stop(ni, tap);
2180 		args[0] = tap->txa_tid;
2181 		args[1] = IEEE80211_DELBAPS_INIT;
2182 		args[2] = reason;			/* XXX reason code */
2183 		ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2184 			IEEE80211_ACTION_BA_DELBA, args);
2185 	} else {
2186 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2187 		    ni, "%s: BA stream for TID %d not running (reason %d)",
2188 		    __func__, tap->txa_tid, reason);
2189 		vap->iv_stats.is_ampdu_stop_failed++;
2190 	}
2191 }
2192 
2193 /* XXX */
2194 static void bar_start_timer(struct ieee80211_tx_ampdu *tap);
2195 
2196 static void
2197 bar_timeout(void *arg)
2198 {
2199 	struct ieee80211_tx_ampdu *tap = arg;
2200 	struct ieee80211_node *ni = tap->txa_ni;
2201 
2202 	KASSERT((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0,
2203 	    ("bar/addba collision, flags 0x%x", tap->txa_flags));
2204 
2205 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2206 	    ni, "%s: tid %u flags 0x%x attempts %d", __func__,
2207 	    tap->txa_tid, tap->txa_flags, tap->txa_attempts);
2208 
2209 	/* guard against race with bar_tx_complete */
2210 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2211 		return;
2212 	/* XXX ? */
2213 	if (tap->txa_attempts >= ieee80211_bar_maxtries) {
2214 		struct ieee80211com *ic = ni->ni_ic;
2215 
2216 		ni->ni_vap->iv_stats.is_ampdu_bar_tx_fail++;
2217 		/*
2218 		 * If (at least) the last BAR TX timeout was due to
2219 		 * an ieee80211_send_bar() failures, then we need
2220 		 * to make sure we notify the driver that a BAR
2221 		 * TX did occur and fail.  This gives the driver
2222 		 * a chance to undo any queue pause that may
2223 		 * have occured.
2224 		 */
2225 		ic->ic_bar_response(ni, tap, 1);
2226 		ieee80211_ampdu_stop(ni, tap, IEEE80211_REASON_TIMEOUT);
2227 	} else {
2228 		ni->ni_vap->iv_stats.is_ampdu_bar_tx_retry++;
2229 		if (ieee80211_send_bar(ni, tap, tap->txa_seqpending) != 0) {
2230 			IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2231 			    ni, "%s: failed to TX, starting timer\n",
2232 			    __func__);
2233 			/*
2234 			 * If ieee80211_send_bar() fails here, the
2235 			 * timer may have stopped and/or the pending
2236 			 * flag may be clear.  Because of this,
2237 			 * fake the BARPEND and reset the timer.
2238 			 * A retransmission attempt will then occur
2239 			 * during the next timeout.
2240 			 */
2241 			/* XXX locking */
2242 			tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2243 			bar_start_timer(tap);
2244 		}
2245 	}
2246 }
2247 
2248 static void
2249 bar_start_timer(struct ieee80211_tx_ampdu *tap)
2250 {
2251 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2252 	    tap->txa_ni,
2253 	    "%s: called",
2254 	    __func__);
2255 	callout_reset(&tap->txa_timer, ieee80211_bar_timeout, bar_timeout, tap);
2256 }
2257 
2258 static void
2259 bar_stop_timer(struct ieee80211_tx_ampdu *tap)
2260 {
2261 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2262 	    tap->txa_ni,
2263 	    "%s: called",
2264 	    __func__);
2265 	callout_stop(&tap->txa_timer);
2266 }
2267 
2268 static void
2269 bar_tx_complete(struct ieee80211_node *ni, void *arg, int status)
2270 {
2271 	struct ieee80211_tx_ampdu *tap = arg;
2272 
2273 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2274 	    ni, "%s: tid %u flags 0x%x pending %d status %d",
2275 	    __func__, tap->txa_tid, tap->txa_flags,
2276 	    callout_pending(&tap->txa_timer), status);
2277 
2278 	ni->ni_vap->iv_stats.is_ampdu_bar_tx++;
2279 	/* XXX locking */
2280 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) &&
2281 	    callout_pending(&tap->txa_timer)) {
2282 		struct ieee80211com *ic = ni->ni_ic;
2283 
2284 		if (status == 0)		/* ACK'd */
2285 			bar_stop_timer(tap);
2286 		ic->ic_bar_response(ni, tap, status);
2287 		/* NB: just let timer expire so we pace requests */
2288 	}
2289 }
2290 
2291 static void
2292 ieee80211_bar_response(struct ieee80211_node *ni,
2293 	struct ieee80211_tx_ampdu *tap, int status)
2294 {
2295 
2296 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2297 	    tap->txa_ni,
2298 	    "%s: called",
2299 	    __func__);
2300 	if (status == 0) {		/* got ACK */
2301 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2302 		    ni, "BAR moves BA win <%u:%u> (%u frames) txseq %u tid %u",
2303 		    tap->txa_start,
2304 		    IEEE80211_SEQ_ADD(tap->txa_start, tap->txa_wnd-1),
2305 		    tap->txa_qframes, tap->txa_seqpending,
2306 		    tap->txa_tid);
2307 
2308 		/* NB: timer already stopped in bar_tx_complete */
2309 		tap->txa_start = tap->txa_seqpending;
2310 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2311 	}
2312 }
2313 
2314 /*
2315  * Transmit a BAR frame to the specified node.  The
2316  * BAR contents are drawn from the supplied aggregation
2317  * state associated with the node.
2318  *
2319  * NB: we only handle immediate ACK w/ compressed bitmap.
2320  */
2321 int
2322 ieee80211_send_bar(struct ieee80211_node *ni,
2323 	struct ieee80211_tx_ampdu *tap, ieee80211_seq seq)
2324 {
2325 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2326 	struct ieee80211vap *vap = ni->ni_vap;
2327 	struct ieee80211com *ic = ni->ni_ic;
2328 	struct ieee80211_frame_bar *bar;
2329 	struct mbuf *m;
2330 	uint16_t barctl, barseqctl;
2331 	uint8_t *frm;
2332 	int tid, ret;
2333 
2334 
2335 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2336 	    tap->txa_ni,
2337 	    "%s: called",
2338 	    __func__);
2339 
2340 	if ((tap->txa_flags & IEEE80211_AGGR_RUNNING) == 0) {
2341 		/* no ADDBA response, should not happen */
2342 		/* XXX stat+msg */
2343 		return EINVAL;
2344 	}
2345 	/* XXX locking */
2346 	bar_stop_timer(tap);
2347 
2348 	ieee80211_ref_node(ni);
2349 
2350 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom, sizeof(*bar));
2351 	if (m == NULL)
2352 		senderr(ENOMEM, is_tx_nobuf);
2353 
2354 	if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
2355 		m_freem(m);
2356 		senderr(ENOMEM, is_tx_nobuf);	/* XXX */
2357 		/* NOTREACHED */
2358 	}
2359 
2360 	bar = mtod(m, struct ieee80211_frame_bar *);
2361 	bar->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2362 		IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_BAR;
2363 	bar->i_fc[1] = 0;
2364 	IEEE80211_ADDR_COPY(bar->i_ra, ni->ni_macaddr);
2365 	IEEE80211_ADDR_COPY(bar->i_ta, vap->iv_myaddr);
2366 
2367 	tid = tap->txa_tid;
2368 	barctl 	= (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE ?
2369 			0 : IEEE80211_BAR_NOACK)
2370 		| IEEE80211_BAR_COMP
2371 		| SM(tid, IEEE80211_BAR_TID)
2372 		;
2373 	barseqctl = SM(seq, IEEE80211_BAR_SEQ_START);
2374 	/* NB: known to have proper alignment */
2375 	bar->i_ctl = htole16(barctl);
2376 	bar->i_seq = htole16(barseqctl);
2377 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_bar);
2378 
2379 	M_WME_SETAC(m, WME_AC_VO);
2380 
2381 	IEEE80211_NODE_STAT(ni, tx_mgmt);	/* XXX tx_ctl? */
2382 
2383 	/* XXX locking */
2384 	/* init/bump attempts counter */
2385 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2386 		tap->txa_attempts = 1;
2387 	else
2388 		tap->txa_attempts++;
2389 	tap->txa_seqpending = seq;
2390 	tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2391 
2392 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2393 	    ni, "send BAR: tid %u ctl 0x%x start %u (attempt %d)",
2394 	    tid, barctl, seq, tap->txa_attempts);
2395 
2396 	/*
2397 	 * ic_raw_xmit will free the node reference
2398 	 * regardless of queue/TX success or failure.
2399 	 */
2400 	IEEE80211_TX_LOCK(ic);
2401 	ret = ieee80211_raw_output(vap, ni, m, NULL);
2402 	IEEE80211_TX_UNLOCK(ic);
2403 	if (ret != 0) {
2404 		IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2405 		    ni, "send BAR: failed: (ret = %d)\n",
2406 		    ret);
2407 		/* xmit failed, clear state flag */
2408 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2409 		vap->iv_stats.is_ampdu_bar_tx_fail++;
2410 		return ret;
2411 	}
2412 	/* XXX hack against tx complete happening before timer is started */
2413 	if (tap->txa_flags & IEEE80211_AGGR_BARPEND)
2414 		bar_start_timer(tap);
2415 	return 0;
2416 bad:
2417 	IEEE80211_NOTE(tap->txa_ni->ni_vap, IEEE80211_MSG_11N,
2418 	    tap->txa_ni,
2419 	    "%s: bad! ret=%d",
2420 	    __func__, ret);
2421 	vap->iv_stats.is_ampdu_bar_tx_fail++;
2422 	ieee80211_free_node(ni);
2423 	return ret;
2424 #undef senderr
2425 }
2426 
2427 static int
2428 ht_action_output(struct ieee80211_node *ni, struct mbuf *m)
2429 {
2430 	struct ieee80211_bpf_params params;
2431 
2432 	memset(&params, 0, sizeof(params));
2433 	params.ibp_pri = WME_AC_VO;
2434 	params.ibp_rate0 = ni->ni_txparms->mgmtrate;
2435 	/* NB: we know all frames are unicast */
2436 	params.ibp_try0 = ni->ni_txparms->maxretry;
2437 	params.ibp_power = ni->ni_txpower;
2438 	return ieee80211_mgmt_output(ni, m, IEEE80211_FC0_SUBTYPE_ACTION,
2439 	     &params);
2440 }
2441 
2442 #define	ADDSHORT(frm, v) do {			\
2443 	frm[0] = (v) & 0xff;			\
2444 	frm[1] = (v) >> 8;			\
2445 	frm += 2;				\
2446 } while (0)
2447 
2448 /*
2449  * Send an action management frame.  The arguments are stuff
2450  * into a frame without inspection; the caller is assumed to
2451  * prepare them carefully (e.g. based on the aggregation state).
2452  */
2453 static int
2454 ht_send_action_ba_addba(struct ieee80211_node *ni,
2455 	int category, int action, void *arg0)
2456 {
2457 	struct ieee80211vap *vap = ni->ni_vap;
2458 	struct ieee80211com *ic = ni->ni_ic;
2459 	uint16_t *args = arg0;
2460 	struct mbuf *m;
2461 	uint8_t *frm;
2462 
2463 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2464 	    "send ADDBA %s: dialogtoken %d status %d "
2465 	    "baparamset 0x%x (tid %d) batimeout 0x%x baseqctl 0x%x",
2466 	    (action == IEEE80211_ACTION_BA_ADDBA_REQUEST) ?
2467 		"request" : "response",
2468 	    args[0], args[1], args[2], MS(args[2], IEEE80211_BAPS_TID),
2469 	    args[3], args[4]);
2470 
2471 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2472 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2473 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2474 	ieee80211_ref_node(ni);
2475 
2476 	m = ieee80211_getmgtframe(&frm,
2477 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2478 	    sizeof(uint16_t)	/* action+category */
2479 	    /* XXX may action payload */
2480 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2481 	);
2482 	if (m != NULL) {
2483 		*frm++ = category;
2484 		*frm++ = action;
2485 		*frm++ = args[0];		/* dialog token */
2486 		if (action == IEEE80211_ACTION_BA_ADDBA_RESPONSE)
2487 			ADDSHORT(frm, args[1]);	/* status code */
2488 		ADDSHORT(frm, args[2]);		/* baparamset */
2489 		ADDSHORT(frm, args[3]);		/* batimeout */
2490 		if (action == IEEE80211_ACTION_BA_ADDBA_REQUEST)
2491 			ADDSHORT(frm, args[4]);	/* baseqctl */
2492 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2493 		return ht_action_output(ni, m);
2494 	} else {
2495 		vap->iv_stats.is_tx_nobuf++;
2496 		ieee80211_free_node(ni);
2497 		return ENOMEM;
2498 	}
2499 }
2500 
2501 static int
2502 ht_send_action_ba_delba(struct ieee80211_node *ni,
2503 	int category, int action, void *arg0)
2504 {
2505 	struct ieee80211vap *vap = ni->ni_vap;
2506 	struct ieee80211com *ic = ni->ni_ic;
2507 	uint16_t *args = arg0;
2508 	struct mbuf *m;
2509 	uint16_t baparamset;
2510 	uint8_t *frm;
2511 
2512 	baparamset = SM(args[0], IEEE80211_DELBAPS_TID)
2513 		   | args[1]
2514 		   ;
2515 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2516 	    "send DELBA action: tid %d, initiator %d reason %d",
2517 	    args[0], args[1], args[2]);
2518 
2519 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2520 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2521 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2522 	ieee80211_ref_node(ni);
2523 
2524 	m = ieee80211_getmgtframe(&frm,
2525 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2526 	    sizeof(uint16_t)	/* action+category */
2527 	    /* XXX may action payload */
2528 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2529 	);
2530 	if (m != NULL) {
2531 		*frm++ = category;
2532 		*frm++ = action;
2533 		ADDSHORT(frm, baparamset);
2534 		ADDSHORT(frm, args[2]);		/* reason code */
2535 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2536 		return ht_action_output(ni, m);
2537 	} else {
2538 		vap->iv_stats.is_tx_nobuf++;
2539 		ieee80211_free_node(ni);
2540 		return ENOMEM;
2541 	}
2542 }
2543 
2544 static int
2545 ht_send_action_ht_txchwidth(struct ieee80211_node *ni,
2546 	int category, int action, void *arg0)
2547 {
2548 	struct ieee80211vap *vap = ni->ni_vap;
2549 	struct ieee80211com *ic = ni->ni_ic;
2550 	struct mbuf *m;
2551 	uint8_t *frm;
2552 
2553 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2554 	    "send HT txchwidth: width %d",
2555 	    IEEE80211_IS_CHAN_HT40(ni->ni_chan) ? 40 : 20);
2556 
2557 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2558 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2559 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2560 	ieee80211_ref_node(ni);
2561 
2562 	m = ieee80211_getmgtframe(&frm,
2563 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2564 	    sizeof(uint16_t)	/* action+category */
2565 	    /* XXX may action payload */
2566 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2567 	);
2568 	if (m != NULL) {
2569 		*frm++ = category;
2570 		*frm++ = action;
2571 		*frm++ = IEEE80211_IS_CHAN_HT40(ni->ni_chan) ?
2572 			IEEE80211_A_HT_TXCHWIDTH_2040 :
2573 			IEEE80211_A_HT_TXCHWIDTH_20;
2574 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2575 		return ht_action_output(ni, m);
2576 	} else {
2577 		vap->iv_stats.is_tx_nobuf++;
2578 		ieee80211_free_node(ni);
2579 		return ENOMEM;
2580 	}
2581 }
2582 #undef ADDSHORT
2583 
2584 /*
2585  * Construct the MCS bit mask for inclusion in an HT capabilities
2586  * information element.
2587  */
2588 static void
2589 ieee80211_set_mcsset(struct ieee80211com *ic, uint8_t *frm)
2590 {
2591 	int i;
2592 	uint8_t txparams;
2593 
2594 	KASSERT((ic->ic_rxstream > 0 && ic->ic_rxstream <= 4),
2595 	    ("ic_rxstream %d out of range", ic->ic_rxstream));
2596 	KASSERT((ic->ic_txstream > 0 && ic->ic_txstream <= 4),
2597 	    ("ic_txstream %d out of range", ic->ic_txstream));
2598 
2599 	for (i = 0; i < ic->ic_rxstream * 8; i++)
2600 		setbit(frm, i);
2601 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
2602 	    (ic->ic_htcaps & IEEE80211_HTC_RXMCS32))
2603 		setbit(frm, 32);
2604 	if (ic->ic_htcaps & IEEE80211_HTC_RXUNEQUAL) {
2605 		if (ic->ic_rxstream >= 2) {
2606 			for (i = 33; i <= 38; i++)
2607 				setbit(frm, i);
2608 		}
2609 		if (ic->ic_rxstream >= 3) {
2610 			for (i = 39; i <= 52; i++)
2611 				setbit(frm, i);
2612 		}
2613 		if (ic->ic_txstream >= 4) {
2614 			for (i = 53; i <= 76; i++)
2615 				setbit(frm, i);
2616 		}
2617 	}
2618 
2619 	if (ic->ic_rxstream != ic->ic_txstream) {
2620 		txparams = 0x1;			/* TX MCS set defined */
2621 		txparams |= 0x2;		/* TX RX MCS not equal */
2622 		txparams |= (ic->ic_txstream - 1) << 2;	/* num TX streams */
2623 		if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL)
2624 			txparams |= 0x16;	/* TX unequal modulation sup */
2625 	} else
2626 		txparams = 0;
2627 	frm[12] = txparams;
2628 }
2629 
2630 /*
2631  * Add body of an HTCAP information element.
2632  */
2633 static uint8_t *
2634 ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
2635 {
2636 #define	ADDSHORT(frm, v) do {			\
2637 	frm[0] = (v) & 0xff;			\
2638 	frm[1] = (v) >> 8;			\
2639 	frm += 2;				\
2640 } while (0)
2641 	struct ieee80211com *ic = ni->ni_ic;
2642 	struct ieee80211vap *vap = ni->ni_vap;
2643 	uint16_t caps, extcaps;
2644 	int rxmax, density;
2645 
2646 	/* HT capabilities */
2647 	caps = vap->iv_htcaps & 0xffff;
2648 	/*
2649 	 * Note channel width depends on whether we are operating as
2650 	 * a sta or not.  When operating as a sta we are generating
2651 	 * a request based on our desired configuration.  Otherwise
2652 	 * we are operational and the channel attributes identify
2653 	 * how we've been setup (which might be different if a fixed
2654 	 * channel is specified).
2655 	 */
2656 	if (vap->iv_opmode == IEEE80211_M_STA) {
2657 		/* override 20/40 use based on config */
2658 		if (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)
2659 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2660 		else
2661 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2662 
2663 		/* Start by using the advertised settings */
2664 		rxmax = MS(ni->ni_htparam, IEEE80211_HTCAP_MAXRXAMPDU);
2665 		density = MS(ni->ni_htparam, IEEE80211_HTCAP_MPDUDENSITY);
2666 
2667 		/* Cap at VAP rxmax */
2668 		if (rxmax > vap->iv_ampdu_rxmax)
2669 			rxmax = vap->iv_ampdu_rxmax;
2670 
2671 		/*
2672 		 * If the VAP ampdu density value greater, use that.
2673 		 *
2674 		 * (Larger density value == larger minimum gap between A-MPDU
2675 		 * subframes.)
2676 		 */
2677 		if (vap->iv_ampdu_density > density)
2678 			density = vap->iv_ampdu_density;
2679 
2680 		/*
2681 		 * NB: Hardware might support HT40 on some but not all
2682 		 * channels. We can't determine this earlier because only
2683 		 * after association the channel is upgraded to HT based
2684 		 * on the negotiated capabilities.
2685 		 */
2686 		if (ni->ni_chan != IEEE80211_CHAN_ANYC &&
2687 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40U) == NULL &&
2688 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40D) == NULL)
2689 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2690 	} else {
2691 		/* override 20/40 use based on current channel */
2692 		if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2693 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2694 		else
2695 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2696 
2697 		/* XXX TODO should it start by using advertised settings? */
2698 		rxmax = vap->iv_ampdu_rxmax;
2699 		density = vap->iv_ampdu_density;
2700 	}
2701 
2702 	/* adjust short GI based on channel and config */
2703 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20) == 0)
2704 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
2705 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40) == 0 ||
2706 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
2707 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
2708 	ADDSHORT(frm, caps);
2709 
2710 	/* HT parameters */
2711 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
2712 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
2713 	     ;
2714 	frm++;
2715 
2716 	/* pre-zero remainder of ie */
2717 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
2718 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
2719 
2720 	/* supported MCS set */
2721 	/*
2722 	 * XXX: For sta mode the rate set should be restricted based
2723 	 * on the AP's capabilities, but ni_htrates isn't setup when
2724 	 * we're called to form an AssocReq frame so for now we're
2725 	 * restricted to the device capabilities.
2726 	 */
2727 	ieee80211_set_mcsset(ni->ni_ic, frm);
2728 
2729 	frm += __offsetof(struct ieee80211_ie_htcap, hc_extcap) -
2730 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
2731 
2732 	/* HT extended capabilities */
2733 	extcaps = vap->iv_htextcaps & 0xffff;
2734 
2735 	ADDSHORT(frm, extcaps);
2736 
2737 	frm += sizeof(struct ieee80211_ie_htcap) -
2738 		__offsetof(struct ieee80211_ie_htcap, hc_txbf);
2739 
2740 	return frm;
2741 #undef ADDSHORT
2742 }
2743 
2744 /*
2745  * Add 802.11n HT capabilities information element
2746  */
2747 uint8_t *
2748 ieee80211_add_htcap(uint8_t *frm, struct ieee80211_node *ni)
2749 {
2750 	frm[0] = IEEE80211_ELEMID_HTCAP;
2751 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
2752 	return ieee80211_add_htcap_body(frm + 2, ni);
2753 }
2754 
2755 /*
2756  * Add Broadcom OUI wrapped standard HTCAP ie; this is
2757  * used for compatibility w/ pre-draft implementations.
2758  */
2759 uint8_t *
2760 ieee80211_add_htcap_vendor(uint8_t *frm, struct ieee80211_node *ni)
2761 {
2762 	frm[0] = IEEE80211_ELEMID_VENDOR;
2763 	frm[1] = 4 + sizeof(struct ieee80211_ie_htcap) - 2;
2764 	frm[2] = (BCM_OUI >> 0) & 0xff;
2765 	frm[3] = (BCM_OUI >> 8) & 0xff;
2766 	frm[4] = (BCM_OUI >> 16) & 0xff;
2767 	frm[5] = BCM_OUI_HTCAP;
2768 	return ieee80211_add_htcap_body(frm + 6, ni);
2769 }
2770 
2771 /*
2772  * Construct the MCS bit mask of basic rates
2773  * for inclusion in an HT information element.
2774  */
2775 static void
2776 ieee80211_set_basic_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2777 {
2778 	int i;
2779 
2780 	for (i = 0; i < rs->rs_nrates; i++) {
2781 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2782 		if ((rs->rs_rates[i] & IEEE80211_RATE_BASIC) &&
2783 		    r < IEEE80211_HTRATE_MAXSIZE) {
2784 			/* NB: this assumes a particular implementation */
2785 			setbit(frm, r);
2786 		}
2787 	}
2788 }
2789 
2790 /*
2791  * Update the HTINFO ie for a beacon frame.
2792  */
2793 void
2794 ieee80211_ht_update_beacon(struct ieee80211vap *vap,
2795 	struct ieee80211_beacon_offsets *bo)
2796 {
2797 #define	PROTMODE	(IEEE80211_HTINFO_OPMODE|IEEE80211_HTINFO_NONHT_PRESENT)
2798 	struct ieee80211_node *ni;
2799 	const struct ieee80211_channel *bsschan;
2800 	struct ieee80211com *ic = vap->iv_ic;
2801 	struct ieee80211_ie_htinfo *ht =
2802 	   (struct ieee80211_ie_htinfo *) bo->bo_htinfo;
2803 
2804 	ni = ieee80211_ref_node(vap->iv_bss);
2805 	bsschan = ni->ni_chan;
2806 
2807 	/* XXX only update on channel change */
2808 	ht->hi_ctrlchannel = ieee80211_chan2ieee(ic, bsschan);
2809 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2810 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PERM;
2811 	else
2812 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PROH;
2813 	if (IEEE80211_IS_CHAN_HT40U(bsschan))
2814 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2815 	else if (IEEE80211_IS_CHAN_HT40D(bsschan))
2816 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2817 	else
2818 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_NONE;
2819 	if (IEEE80211_IS_CHAN_HT40(bsschan))
2820 		ht->hi_byte1 |= IEEE80211_HTINFO_TXWIDTH_2040;
2821 
2822 	/* protection mode */
2823 	ht->hi_byte2 = (ht->hi_byte2 &~ PROTMODE) | ic->ic_curhtprotmode;
2824 
2825 	ieee80211_free_node(ni);
2826 
2827 	/* XXX propagate to vendor ie's */
2828 #undef PROTMODE
2829 }
2830 
2831 /*
2832  * Add body of an HTINFO information element.
2833  *
2834  * NB: We don't use struct ieee80211_ie_htinfo because we can
2835  * be called to fillin both a standard ie and a compat ie that
2836  * has a vendor OUI at the front.
2837  */
2838 static uint8_t *
2839 ieee80211_add_htinfo_body(uint8_t *frm, struct ieee80211_node *ni)
2840 {
2841 	struct ieee80211vap *vap = ni->ni_vap;
2842 	struct ieee80211com *ic = ni->ni_ic;
2843 
2844 	/* pre-zero remainder of ie */
2845 	memset(frm, 0, sizeof(struct ieee80211_ie_htinfo) - 2);
2846 
2847 	/* primary/control channel center */
2848 	*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2849 
2850 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2851 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PERM;
2852 	else
2853 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PROH;
2854 	if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
2855 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2856 	else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
2857 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2858 	else
2859 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_NONE;
2860 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2861 		frm[0] |= IEEE80211_HTINFO_TXWIDTH_2040;
2862 
2863 	frm[1] = ic->ic_curhtprotmode;
2864 
2865 	frm += 5;
2866 
2867 	/* basic MCS set */
2868 	ieee80211_set_basic_htrates(frm, &ni->ni_htrates);
2869 	frm += sizeof(struct ieee80211_ie_htinfo) -
2870 		__offsetof(struct ieee80211_ie_htinfo, hi_basicmcsset);
2871 	return frm;
2872 }
2873 
2874 /*
2875  * Add 802.11n HT information information element.
2876  */
2877 uint8_t *
2878 ieee80211_add_htinfo(uint8_t *frm, struct ieee80211_node *ni)
2879 {
2880 	frm[0] = IEEE80211_ELEMID_HTINFO;
2881 	frm[1] = sizeof(struct ieee80211_ie_htinfo) - 2;
2882 	return ieee80211_add_htinfo_body(frm + 2, ni);
2883 }
2884 
2885 /*
2886  * Add Broadcom OUI wrapped standard HTINFO ie; this is
2887  * used for compatibility w/ pre-draft implementations.
2888  */
2889 uint8_t *
2890 ieee80211_add_htinfo_vendor(uint8_t *frm, struct ieee80211_node *ni)
2891 {
2892 	frm[0] = IEEE80211_ELEMID_VENDOR;
2893 	frm[1] = 4 + sizeof(struct ieee80211_ie_htinfo) - 2;
2894 	frm[2] = (BCM_OUI >> 0) & 0xff;
2895 	frm[3] = (BCM_OUI >> 8) & 0xff;
2896 	frm[4] = (BCM_OUI >> 16) & 0xff;
2897 	frm[5] = BCM_OUI_HTINFO;
2898 	return ieee80211_add_htinfo_body(frm + 6, ni);
2899 }
2900