xref: /freebsd/sys/net80211/ieee80211_ht.c (revision 5c52a79884070364bfc920fb8e492cfac61ec72f)
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_media.h>
47 #include <net/ethernet.h>
48 
49 #include <net80211/ieee80211_var.h>
50 #include <net80211/ieee80211_input.h>
51 
52 /* define here, used throughout file */
53 #define	MS(_v, _f)	(((_v) & _f) >> _f##_S)
54 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
55 
56 const struct ieee80211_mcs_rates ieee80211_htrates[16] = {
57 	{  13,  14,  27,  30 },	/* MCS 0 */
58 	{  26,  29,  54,  60 },	/* MCS 1 */
59 	{  39,  43,  81,  90 },	/* MCS 2 */
60 	{  52,  58, 108, 120 },	/* MCS 3 */
61 	{  78,  87, 162, 180 },	/* MCS 4 */
62 	{ 104, 116, 216, 240 },	/* MCS 5 */
63 	{ 117, 130, 243, 270 },	/* MCS 6 */
64 	{ 130, 144, 270, 300 },	/* MCS 7 */
65 	{  26,  29,  54,  60 },	/* MCS 8 */
66 	{  52,  58, 108, 120 },	/* MCS 9 */
67 	{  78,  87, 162, 180 },	/* MCS 10 */
68 	{ 104, 116, 216, 240 },	/* MCS 11 */
69 	{ 156, 173, 324, 360 },	/* MCS 12 */
70 	{ 208, 231, 432, 480 },	/* MCS 13 */
71 	{ 234, 260, 486, 540 },	/* MCS 14 */
72 	{ 260, 289, 540, 600 }	/* MCS 15 */
73 };
74 
75 static const struct ieee80211_htrateset ieee80211_rateset_11n =
76 	{ 16, {
77 	          0,   1,   2,   3,   4,  5,   6,  7,  8,  9,
78 		 10,  11,  12,  13,  14,  15 }
79 	};
80 
81 #ifdef IEEE80211_AMPDU_AGE
82 /* XXX public for sysctl hookup */
83 int	ieee80211_ampdu_age = -1;	/* threshold for ampdu reorder q (ms) */
84 #endif
85 int	ieee80211_recv_bar_ena = 1;
86 int	ieee80211_addba_timeout = -1;	/* timeout waiting for ADDBA response */
87 int	ieee80211_addba_backoff = -1;	/* backoff after max ADDBA requests */
88 int	ieee80211_addba_maxtries = 3;	/* max ADDBA requests before backoff */
89 int	ieee80211_bar_timeout = -1;	/* timeout waiting for BAR response */
90 int	ieee80211_bar_maxtries = 50;	/* max BAR requests before DELBA */
91 
92 /*
93  * Setup HT parameters that depends on the clock frequency.
94  */
95 static void
96 ieee80211_ht_setup(void)
97 {
98 #ifdef IEEE80211_AMPDU_AGE
99 	ieee80211_ampdu_age = msecs_to_ticks(500);
100 #endif
101 	ieee80211_addba_timeout = msecs_to_ticks(250);
102 	ieee80211_addba_backoff = msecs_to_ticks(10*1000);
103 	ieee80211_bar_timeout = msecs_to_ticks(250);
104 }
105 SYSINIT(wlan_ht, SI_SUB_DRIVERS, SI_ORDER_FIRST, ieee80211_ht_setup, NULL);
106 
107 static int ieee80211_ampdu_enable(struct ieee80211_node *ni,
108 	struct ieee80211_tx_ampdu *tap);
109 static int ieee80211_addba_request(struct ieee80211_node *ni,
110 	struct ieee80211_tx_ampdu *tap,
111 	int dialogtoken, int baparamset, int batimeout);
112 static int ieee80211_addba_response(struct ieee80211_node *ni,
113 	struct ieee80211_tx_ampdu *tap,
114 	int code, int baparamset, int batimeout);
115 static void ieee80211_addba_stop(struct ieee80211_node *ni,
116 	struct ieee80211_tx_ampdu *tap);
117 static void ieee80211_aggr_recv_action(struct ieee80211_node *ni,
118 	const uint8_t *frm, const uint8_t *efrm);
119 static void ieee80211_bar_response(struct ieee80211_node *ni,
120 	struct ieee80211_tx_ampdu *tap, int status);
121 static void ampdu_tx_stop(struct ieee80211_tx_ampdu *tap);
122 static void bar_stop_timer(struct ieee80211_tx_ampdu *tap);
123 
124 void
125 ieee80211_ht_attach(struct ieee80211com *ic)
126 {
127 	/* setup default aggregation policy */
128 	ic->ic_recv_action = ieee80211_aggr_recv_action;
129 	ic->ic_send_action = ieee80211_send_action;
130 	ic->ic_ampdu_enable = ieee80211_ampdu_enable;
131 	ic->ic_addba_request = ieee80211_addba_request;
132 	ic->ic_addba_response = ieee80211_addba_response;
133 	ic->ic_addba_stop = ieee80211_addba_stop;
134 	ic->ic_bar_response = ieee80211_bar_response;
135 
136 	ic->ic_htprotmode = IEEE80211_PROT_RTSCTS;
137 	ic->ic_curhtprotmode = IEEE80211_HTINFO_OPMODE_PURE;
138 }
139 
140 void
141 ieee80211_ht_detach(struct ieee80211com *ic)
142 {
143 }
144 
145 void
146 ieee80211_ht_vattach(struct ieee80211vap *vap)
147 {
148 
149 	/* driver can override defaults */
150 	vap->iv_ampdu_rxmax = IEEE80211_HTCAP_MAXRXAMPDU_8K;
151 	vap->iv_ampdu_density = IEEE80211_HTCAP_MPDUDENSITY_NA;
152 	vap->iv_ampdu_limit = vap->iv_ampdu_rxmax;
153 	vap->iv_amsdu_limit = vap->iv_htcaps & IEEE80211_HTCAP_MAXAMSDU;
154 	/* tx aggregation traffic thresholds */
155 	vap->iv_ampdu_mintraffic[WME_AC_BK] = 128;
156 	vap->iv_ampdu_mintraffic[WME_AC_BE] = 64;
157 	vap->iv_ampdu_mintraffic[WME_AC_VO] = 32;
158 	vap->iv_ampdu_mintraffic[WME_AC_VI] = 32;
159 
160 	if (vap->iv_htcaps & IEEE80211_HTC_HT) {
161 		/*
162 		 * Device is HT capable; enable all HT-related
163 		 * facilities by default.
164 		 * XXX these choices may be too aggressive.
165 		 */
166 		vap->iv_flags_ext |= IEEE80211_FEXT_HT
167 				  |  IEEE80211_FEXT_HTCOMPAT
168 				  ;
169 		if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI20)
170 			vap->iv_flags_ext |= IEEE80211_FEXT_SHORTGI20;
171 		/* XXX infer from channel list? */
172 		if (vap->iv_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
173 			vap->iv_flags_ext |= IEEE80211_FEXT_USEHT40;
174 			if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI40)
175 				vap->iv_flags_ext |= IEEE80211_FEXT_SHORTGI40;
176 		}
177 		/* enable RIFS if capable */
178 		if (vap->iv_htcaps & IEEE80211_HTC_RIFS)
179 			vap->iv_flags_ext |= IEEE80211_FEXT_RIFS;
180 
181 		/* NB: A-MPDU and A-MSDU rx are mandated, these are tx only */
182 		vap->iv_flags_ext |= IEEE80211_FEXT_AMPDU_RX;
183 		if (vap->iv_htcaps & IEEE80211_HTC_AMPDU)
184 			vap->iv_flags_ext |= IEEE80211_FEXT_AMPDU_TX;
185 		vap->iv_flags_ext |= IEEE80211_FEXT_AMSDU_RX;
186 		if (vap->iv_htcaps & IEEE80211_HTC_AMSDU)
187 			vap->iv_flags_ext |= IEEE80211_FEXT_AMSDU_TX;
188 	}
189 	/* NB: disable default legacy WDS, too many issues right now */
190 	if (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)
191 		vap->iv_flags_ext &= ~IEEE80211_FEXT_HT;
192 }
193 
194 void
195 ieee80211_ht_vdetach(struct ieee80211vap *vap)
196 {
197 }
198 
199 static void
200 ht_announce(struct ieee80211com *ic, int mode,
201 	const struct ieee80211_htrateset *rs)
202 {
203 	struct ifnet *ifp = ic->ic_ifp;
204 	int i, rate, mword;
205 
206 	if_printf(ifp, "%s MCS: ", ieee80211_phymode_name[mode]);
207 	for (i = 0; i < rs->rs_nrates; i++) {
208 		mword = ieee80211_rate2media(ic,
209 		    rs->rs_rates[i] | IEEE80211_RATE_MCS, mode);
210 		if (IFM_SUBTYPE(mword) != IFM_IEEE80211_MCS)
211 			continue;
212 		rate = ieee80211_htrates[rs->rs_rates[i]].ht40_rate_400ns;
213 		printf("%s%d%sMbps", (i != 0 ? " " : ""),
214 		    rate / 2, ((rate & 0x1) != 0 ? ".5" : ""));
215 	}
216 	printf("\n");
217 }
218 
219 void
220 ieee80211_ht_announce(struct ieee80211com *ic)
221 {
222 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
223 		ht_announce(ic, IEEE80211_MODE_11NA, &ieee80211_rateset_11n);
224 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
225 		ht_announce(ic, IEEE80211_MODE_11NG, &ieee80211_rateset_11n);
226 }
227 
228 const struct ieee80211_htrateset *
229 ieee80211_get_suphtrates(struct ieee80211com *ic,
230 	const struct ieee80211_channel *c)
231 {
232 	return &ieee80211_rateset_11n;
233 }
234 
235 /*
236  * Receive processing.
237  */
238 
239 /*
240  * Decap the encapsulated A-MSDU frames and dispatch all but
241  * the last for delivery.  The last frame is returned for
242  * delivery via the normal path.
243  */
244 struct mbuf *
245 ieee80211_decap_amsdu(struct ieee80211_node *ni, struct mbuf *m)
246 {
247 	struct ieee80211vap *vap = ni->ni_vap;
248 	int framelen;
249 	struct mbuf *n;
250 
251 	/* discard 802.3 header inserted by ieee80211_decap */
252 	m_adj(m, sizeof(struct ether_header));
253 
254 	vap->iv_stats.is_amsdu_decap++;
255 
256 	for (;;) {
257 		/*
258 		 * Decap the first frame, bust it apart from the
259 		 * remainder and deliver.  We leave the last frame
260 		 * delivery to the caller (for consistency with other
261 		 * code paths, could also do it here).
262 		 */
263 		m = ieee80211_decap1(m, &framelen);
264 		if (m == NULL) {
265 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
266 			    ni->ni_macaddr, "a-msdu", "%s", "decap failed");
267 			vap->iv_stats.is_amsdu_tooshort++;
268 			return NULL;
269 		}
270 		if (m->m_pkthdr.len == framelen)
271 			break;
272 		n = m_split(m, framelen, M_NOWAIT);
273 		if (n == NULL) {
274 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
275 			    ni->ni_macaddr, "a-msdu",
276 			    "%s", "unable to split encapsulated frames");
277 			vap->iv_stats.is_amsdu_split++;
278 			m_freem(m);			/* NB: must reclaim */
279 			return NULL;
280 		}
281 		vap->iv_deliver_data(vap, ni, m);
282 
283 		/*
284 		 * Remove frame contents; each intermediate frame
285 		 * is required to be aligned to a 4-byte boundary.
286 		 */
287 		m = n;
288 		m_adj(m, roundup2(framelen, 4) - framelen);	/* padding */
289 	}
290 	return m;				/* last delivered by caller */
291 }
292 
293 /*
294  * Purge all frames in the A-MPDU re-order queue.
295  */
296 static void
297 ampdu_rx_purge(struct ieee80211_rx_ampdu *rap)
298 {
299 	struct mbuf *m;
300 	int i;
301 
302 	for (i = 0; i < rap->rxa_wnd; i++) {
303 		m = rap->rxa_m[i];
304 		if (m != NULL) {
305 			rap->rxa_m[i] = NULL;
306 			rap->rxa_qbytes -= m->m_pkthdr.len;
307 			m_freem(m);
308 			if (--rap->rxa_qframes == 0)
309 				break;
310 		}
311 	}
312 	KASSERT(rap->rxa_qbytes == 0 && rap->rxa_qframes == 0,
313 	    ("lost %u data, %u frames on ampdu rx q",
314 	    rap->rxa_qbytes, rap->rxa_qframes));
315 }
316 
317 /*
318  * Start A-MPDU rx/re-order processing for the specified TID.
319  */
320 static void
321 ampdu_rx_start(struct ieee80211_rx_ampdu *rap, int bufsiz, int start)
322 {
323 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
324 		/*
325 		 * AMPDU previously setup and not terminated with a DELBA,
326 		 * flush the reorder q's in case anything remains.
327 		 */
328 		ampdu_rx_purge(rap);
329 	}
330 	memset(rap, 0, sizeof(*rap));
331 	rap->rxa_wnd = (bufsiz == 0) ?
332 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
333 	rap->rxa_start = start;
334 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
335 }
336 
337 /*
338  * Stop A-MPDU rx processing for the specified TID.
339  */
340 static void
341 ampdu_rx_stop(struct ieee80211_rx_ampdu *rap)
342 {
343 	ampdu_rx_purge(rap);
344 	rap->rxa_flags &= ~(IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND);
345 }
346 
347 /*
348  * Dispatch a frame from the A-MPDU reorder queue.  The
349  * frame is fed back into ieee80211_input marked with an
350  * M_AMPDU_MPDU flag so it doesn't come back to us (it also
351  * permits ieee80211_input to optimize re-processing).
352  */
353 static __inline void
354 ampdu_dispatch(struct ieee80211_node *ni, struct mbuf *m)
355 {
356 	m->m_flags |= M_AMPDU_MPDU;	/* bypass normal processing */
357 	/* NB: rssi, noise, and rstamp are ignored w/ M_AMPDU_MPDU set */
358 	(void) ieee80211_input(ni, m, 0, 0, 0);
359 }
360 
361 /*
362  * Dispatch as many frames as possible from the re-order queue.
363  * Frames will always be "at the front"; we process all frames
364  * up to the first empty slot in the window.  On completion we
365  * cleanup state if there are still pending frames in the current
366  * BA window.  We assume the frame at slot 0 is already handled
367  * by the caller; we always start at slot 1.
368  */
369 static void
370 ampdu_rx_dispatch(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni)
371 {
372 	struct ieee80211vap *vap = ni->ni_vap;
373 	struct mbuf *m;
374 	int i;
375 
376 	/* flush run of frames */
377 	for (i = 1; i < rap->rxa_wnd; i++) {
378 		m = rap->rxa_m[i];
379 		if (m == NULL)
380 			break;
381 		rap->rxa_m[i] = NULL;
382 		rap->rxa_qbytes -= m->m_pkthdr.len;
383 		rap->rxa_qframes--;
384 
385 		ampdu_dispatch(ni, m);
386 	}
387 	/*
388 	 * If frames remain, copy the mbuf pointers down so
389 	 * they correspond to the offsets in the new window.
390 	 */
391 	if (rap->rxa_qframes != 0) {
392 		int n = rap->rxa_qframes, j;
393 		for (j = i+1; j < rap->rxa_wnd; j++) {
394 			if (rap->rxa_m[j] != NULL) {
395 				rap->rxa_m[j-i] = rap->rxa_m[j];
396 				rap->rxa_m[j] = NULL;
397 				if (--n == 0)
398 					break;
399 			}
400 		}
401 		KASSERT(n == 0, ("lost %d frames", n));
402 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
403 	}
404 	/*
405 	 * Adjust the start of the BA window to
406 	 * reflect the frames just dispatched.
407 	 */
408 	rap->rxa_start = IEEE80211_SEQ_ADD(rap->rxa_start, i);
409 	vap->iv_stats.is_ampdu_rx_oor += i;
410 }
411 
412 #ifdef IEEE80211_AMPDU_AGE
413 /*
414  * Dispatch all frames in the A-MPDU re-order queue.
415  */
416 static void
417 ampdu_rx_flush(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
418 {
419 	struct ieee80211vap *vap = ni->ni_vap;
420 	struct mbuf *m;
421 	int i;
422 
423 	for (i = 0; i < rap->rxa_wnd; i++) {
424 		m = rap->rxa_m[i];
425 		if (m == NULL)
426 			continue;
427 		rap->rxa_m[i] = NULL;
428 		rap->rxa_qbytes -= m->m_pkthdr.len;
429 		rap->rxa_qframes--;
430 		vap->iv_stats.is_ampdu_rx_oor++;
431 
432 		ampdu_dispatch(ni, m);
433 		if (rap->rxa_qframes == 0)
434 			break;
435 	}
436 }
437 #endif /* IEEE80211_AMPDU_AGE */
438 
439 /*
440  * Dispatch all frames in the A-MPDU re-order queue
441  * preceding the specified sequence number.  This logic
442  * handles window moves due to a received MSDU or BAR.
443  */
444 static void
445 ampdu_rx_flush_upto(struct ieee80211_node *ni,
446 	struct ieee80211_rx_ampdu *rap, ieee80211_seq winstart)
447 {
448 	struct ieee80211vap *vap = ni->ni_vap;
449 	struct mbuf *m;
450 	ieee80211_seq seqno;
451 	int i;
452 
453 	/*
454 	 * Flush any complete MSDU's with a sequence number lower
455 	 * than winstart.  Gaps may exist.  Note that we may actually
456 	 * dispatch frames past winstart if a run continues; this is
457 	 * an optimization that avoids having to do a separate pass
458 	 * to dispatch frames after moving the BA window start.
459 	 */
460 	seqno = rap->rxa_start;
461 	for (i = 0; i < rap->rxa_wnd; i++) {
462 		m = rap->rxa_m[i];
463 		if (m != NULL) {
464 			rap->rxa_m[i] = NULL;
465 			rap->rxa_qbytes -= m->m_pkthdr.len;
466 			rap->rxa_qframes--;
467 			vap->iv_stats.is_ampdu_rx_oor++;
468 
469 			ampdu_dispatch(ni, m);
470 		} else {
471 			if (!IEEE80211_SEQ_BA_BEFORE(seqno, winstart))
472 				break;
473 		}
474 		seqno = IEEE80211_SEQ_INC(seqno);
475 	}
476 	/*
477 	 * If frames remain, copy the mbuf pointers down so
478 	 * they correspond to the offsets in the new window.
479 	 */
480 	if (rap->rxa_qframes != 0) {
481 		int n = rap->rxa_qframes, j;
482 
483 		/* NB: this loop assumes i > 0 and/or rxa_m[0] is NULL */
484 		KASSERT(rap->rxa_m[0] == NULL,
485 		    ("%s: BA window slot 0 occupied", __func__));
486 		for (j = i+1; j < rap->rxa_wnd; j++) {
487 			if (rap->rxa_m[j] != NULL) {
488 				rap->rxa_m[j-i] = rap->rxa_m[j];
489 				rap->rxa_m[j] = NULL;
490 				if (--n == 0)
491 					break;
492 			}
493 		}
494 		KASSERT(n == 0, ("%s: lost %d frames, qframes %d off %d "
495 		    "BA win <%d:%d> winstart %d",
496 		    __func__, n, rap->rxa_qframes, i, rap->rxa_start,
497 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
498 		    winstart));
499 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
500 	}
501 	/*
502 	 * Move the start of the BA window; we use the
503 	 * sequence number of the last MSDU that was
504 	 * passed up the stack+1 or winstart if stopped on
505 	 * a gap in the reorder buffer.
506 	 */
507 	rap->rxa_start = seqno;
508 }
509 
510 /*
511  * Process a received QoS data frame for an HT station.  Handle
512  * A-MPDU reordering: if this frame is received out of order
513  * and falls within the BA window hold onto it.  Otherwise if
514  * this frame completes a run, flush any pending frames.  We
515  * return 1 if the frame is consumed.  A 0 is returned if
516  * the frame should be processed normally by the caller.
517  */
518 int
519 ieee80211_ampdu_reorder(struct ieee80211_node *ni, struct mbuf *m)
520 {
521 #define	IEEE80211_FC0_QOSDATA \
522 	(IEEE80211_FC0_TYPE_DATA|IEEE80211_FC0_SUBTYPE_QOS|IEEE80211_FC0_VERSION_0)
523 #define	PROCESS		0	/* caller should process frame */
524 #define	CONSUMED	1	/* frame consumed, caller does nothing */
525 	struct ieee80211vap *vap = ni->ni_vap;
526 	struct ieee80211_qosframe *wh;
527 	struct ieee80211_rx_ampdu *rap;
528 	ieee80211_seq rxseq;
529 	uint8_t tid;
530 	int off;
531 
532 	KASSERT((m->m_flags & (M_AMPDU | M_AMPDU_MPDU)) == M_AMPDU,
533 	    ("!a-mpdu or already re-ordered, flags 0x%x", m->m_flags));
534 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
535 
536 	/* NB: m_len known to be sufficient */
537 	wh = mtod(m, struct ieee80211_qosframe *);
538 	if (wh->i_fc[0] != IEEE80211_FC0_QOSDATA) {
539 		/*
540 		 * Not QoS data, shouldn't get here but just
541 		 * return it to the caller for processing.
542 		 */
543 		return PROCESS;
544 	}
545 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
546 		tid = ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0];
547 	else
548 		tid = wh->i_qos[0];
549 	tid &= IEEE80211_QOS_TID;
550 	rap = &ni->ni_rx_ampdu[tid];
551 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
552 		/*
553 		 * No ADDBA request yet, don't touch.
554 		 */
555 		return PROCESS;
556 	}
557 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
558 	if ((rxseq & IEEE80211_SEQ_FRAG_MASK) != 0) {
559 		/*
560 		 * Fragments are not allowed; toss.
561 		 */
562 		IEEE80211_DISCARD_MAC(vap,
563 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
564 		    "A-MPDU", "fragment, rxseq 0x%x tid %u%s", rxseq, tid,
565 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
566 		vap->iv_stats.is_ampdu_rx_drop++;
567 		IEEE80211_NODE_STAT(ni, rx_drop);
568 		m_freem(m);
569 		return CONSUMED;
570 	}
571 	rxseq >>= IEEE80211_SEQ_SEQ_SHIFT;
572 	rap->rxa_nframes++;
573 again:
574 	if (rxseq == rap->rxa_start) {
575 		/*
576 		 * First frame in window.
577 		 */
578 		if (rap->rxa_qframes != 0) {
579 			/*
580 			 * Dispatch as many packets as we can.
581 			 */
582 			KASSERT(rap->rxa_m[0] == NULL, ("unexpected dup"));
583 			ampdu_dispatch(ni, m);
584 			ampdu_rx_dispatch(rap, ni);
585 			return CONSUMED;
586 		} else {
587 			/*
588 			 * In order; advance window and notify
589 			 * caller to dispatch directly.
590 			 */
591 			rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
592 			return PROCESS;
593 		}
594 	}
595 	/*
596 	 * Frame is out of order; store if in the BA window.
597 	 */
598 	/* calculate offset in BA window */
599 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
600 	if (off < rap->rxa_wnd) {
601 		/*
602 		 * Common case (hopefully): in the BA window.
603 		 * Sec 9.10.7.6 a) (D2.04 p.118 line 47)
604 		 */
605 #ifdef IEEE80211_AMPDU_AGE
606 		/*
607 		 * Check for frames sitting too long in the reorder queue.
608 		 * This should only ever happen if frames are not delivered
609 		 * without the sender otherwise notifying us (e.g. with a
610 		 * BAR to move the window).  Typically this happens because
611 		 * of vendor bugs that cause the sequence number to jump.
612 		 * When this happens we get a gap in the reorder queue that
613 		 * leaves frame sitting on the queue until they get pushed
614 		 * out due to window moves.  When the vendor does not send
615 		 * BAR this move only happens due to explicit packet sends
616 		 *
617 		 * NB: we only track the time of the oldest frame in the
618 		 * reorder q; this means that if we flush we might push
619 		 * frames that still "new"; if this happens then subsequent
620 		 * frames will result in BA window moves which cost something
621 		 * but is still better than a big throughput dip.
622 		 */
623 		if (rap->rxa_qframes != 0) {
624 			/* XXX honor batimeout? */
625 			if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
626 				/*
627 				 * Too long since we received the first
628 				 * frame; flush the reorder buffer.
629 				 */
630 				if (rap->rxa_qframes != 0) {
631 					vap->iv_stats.is_ampdu_rx_age +=
632 					    rap->rxa_qframes;
633 					ampdu_rx_flush(ni, rap);
634 				}
635 				rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
636 				return PROCESS;
637 			}
638 		} else {
639 			/*
640 			 * First frame, start aging timer.
641 			 */
642 			rap->rxa_age = ticks;
643 		}
644 #endif /* IEEE80211_AMPDU_AGE */
645 		/* save packet */
646 		if (rap->rxa_m[off] == NULL) {
647 			rap->rxa_m[off] = m;
648 			rap->rxa_qframes++;
649 			rap->rxa_qbytes += m->m_pkthdr.len;
650 			vap->iv_stats.is_ampdu_rx_reorder++;
651 		} else {
652 			IEEE80211_DISCARD_MAC(vap,
653 			    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
654 			    ni->ni_macaddr, "a-mpdu duplicate",
655 			    "seqno %u tid %u BA win <%u:%u>",
656 			    rxseq, tid, rap->rxa_start,
657 			    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1));
658 			vap->iv_stats.is_rx_dup++;
659 			IEEE80211_NODE_STAT(ni, rx_dup);
660 			m_freem(m);
661 		}
662 		return CONSUMED;
663 	}
664 	if (off < IEEE80211_SEQ_BA_RANGE) {
665 		/*
666 		 * Outside the BA window, but within range;
667 		 * flush the reorder q and move the window.
668 		 * Sec 9.10.7.6 b) (D2.04 p.118 line 60)
669 		 */
670 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
671 		    "move BA win <%u:%u> (%u frames) rxseq %u tid %u",
672 		    rap->rxa_start,
673 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
674 		    rap->rxa_qframes, rxseq, tid);
675 		vap->iv_stats.is_ampdu_rx_move++;
676 
677 		/*
678 		 * The spec says to flush frames up to but not including:
679 		 * 	WinStart_B = rxseq - rap->rxa_wnd + 1
680 		 * Then insert the frame or notify the caller to process
681 		 * it immediately.  We can safely do this by just starting
682 		 * over again because we know the frame will now be within
683 		 * the BA window.
684 		 */
685 		/* NB: rxa_wnd known to be >0 */
686 		ampdu_rx_flush_upto(ni, rap,
687 		    IEEE80211_SEQ_SUB(rxseq, rap->rxa_wnd-1));
688 		goto again;
689 	} else {
690 		/*
691 		 * Outside the BA window and out of range; toss.
692 		 * Sec 9.10.7.6 c) (D2.04 p.119 line 16)
693 		 */
694 		IEEE80211_DISCARD_MAC(vap,
695 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
696 		    "MPDU", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
697 		    rap->rxa_start,
698 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
699 		    rap->rxa_qframes, rxseq, tid,
700 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
701 		vap->iv_stats.is_ampdu_rx_drop++;
702 		IEEE80211_NODE_STAT(ni, rx_drop);
703 		m_freem(m);
704 		return CONSUMED;
705 	}
706 #undef CONSUMED
707 #undef PROCESS
708 #undef IEEE80211_FC0_QOSDATA
709 }
710 
711 /*
712  * Process a BAR ctl frame.  Dispatch all frames up to
713  * the sequence number of the frame.  If this frame is
714  * out of range it's discarded.
715  */
716 void
717 ieee80211_recv_bar(struct ieee80211_node *ni, struct mbuf *m0)
718 {
719 	struct ieee80211vap *vap = ni->ni_vap;
720 	struct ieee80211_frame_bar *wh;
721 	struct ieee80211_rx_ampdu *rap;
722 	ieee80211_seq rxseq;
723 	int tid, off;
724 
725 	if (!ieee80211_recv_bar_ena) {
726 #if 0
727 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_11N,
728 		    ni->ni_macaddr, "BAR", "%s", "processing disabled");
729 #endif
730 		vap->iv_stats.is_ampdu_bar_bad++;
731 		return;
732 	}
733 	wh = mtod(m0, struct ieee80211_frame_bar *);
734 	/* XXX check basic BAR */
735 	tid = MS(le16toh(wh->i_ctl), IEEE80211_BAR_TID);
736 	rap = &ni->ni_rx_ampdu[tid];
737 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
738 		/*
739 		 * No ADDBA request yet, don't touch.
740 		 */
741 		IEEE80211_DISCARD_MAC(vap,
742 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
743 		    ni->ni_macaddr, "BAR", "no BA stream, tid %u", tid);
744 		vap->iv_stats.is_ampdu_bar_bad++;
745 		return;
746 	}
747 	vap->iv_stats.is_ampdu_bar_rx++;
748 	rxseq = le16toh(wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
749 	if (rxseq == rap->rxa_start)
750 		return;
751 	/* calculate offset in BA window */
752 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
753 	if (off < IEEE80211_SEQ_BA_RANGE) {
754 		/*
755 		 * Flush the reorder q up to rxseq and move the window.
756 		 * Sec 9.10.7.6 a) (D2.04 p.119 line 22)
757 		 */
758 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
759 		    "BAR moves BA win <%u:%u> (%u frames) rxseq %u tid %u",
760 		    rap->rxa_start,
761 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
762 		    rap->rxa_qframes, rxseq, tid);
763 		vap->iv_stats.is_ampdu_bar_move++;
764 
765 		ampdu_rx_flush_upto(ni, rap, rxseq);
766 		if (off >= rap->rxa_wnd) {
767 			/*
768 			 * BAR specifies a window start to the right of BA
769 			 * window; we must move it explicitly since
770 			 * ampdu_rx_flush_upto will not.
771 			 */
772 			rap->rxa_start = rxseq;
773 		}
774 	} else {
775 		/*
776 		 * Out of range; toss.
777 		 * Sec 9.10.7.6 b) (D2.04 p.119 line 41)
778 		 */
779 		IEEE80211_DISCARD_MAC(vap,
780 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
781 		    "BAR", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
782 		    rap->rxa_start,
783 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
784 		    rap->rxa_qframes, rxseq, tid,
785 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
786 		vap->iv_stats.is_ampdu_bar_oow++;
787 		IEEE80211_NODE_STAT(ni, rx_drop);
788 	}
789 }
790 
791 /*
792  * Setup HT-specific state in a node.  Called only
793  * when HT use is negotiated so we don't do extra
794  * work for temporary and/or legacy sta's.
795  */
796 void
797 ieee80211_ht_node_init(struct ieee80211_node *ni)
798 {
799 	struct ieee80211_tx_ampdu *tap;
800 	int ac;
801 
802 	if (ni->ni_flags & IEEE80211_NODE_HT) {
803 		/*
804 		 * Clean AMPDU state on re-associate.  This handles the case
805 		 * where a station leaves w/o notifying us and then returns
806 		 * before node is reaped for inactivity.
807 		 */
808 		ieee80211_ht_node_cleanup(ni);
809 	}
810 	for (ac = 0; ac < WME_NUM_AC; ac++) {
811 		tap = &ni->ni_tx_ampdu[ac];
812 		tap->txa_ac = ac;
813 		tap->txa_ni = ni;
814 		/* NB: further initialization deferred */
815 	}
816 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
817 }
818 
819 /*
820  * Cleanup HT-specific state in a node.  Called only
821  * when HT use has been marked.
822  */
823 void
824 ieee80211_ht_node_cleanup(struct ieee80211_node *ni)
825 {
826 	int i;
827 
828 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT node"));
829 
830 	/* XXX optimize this */
831 	for (i = 0; i < WME_NUM_AC; i++) {
832 		struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[i];
833 		if (tap->txa_flags & IEEE80211_AGGR_SETUP)
834 			ampdu_tx_stop(tap);
835 	}
836 	for (i = 0; i < WME_NUM_TID; i++)
837 		ampdu_rx_stop(&ni->ni_rx_ampdu[i]);
838 
839 	ni->ni_htcap = 0;
840 	ni->ni_flags &= ~IEEE80211_NODE_HT_ALL;
841 }
842 
843 /*
844  * Age out HT resources for a station.
845  */
846 void
847 ieee80211_ht_node_age(struct ieee80211_node *ni)
848 {
849 #ifdef IEEE80211_AMPDU_AGE
850 	struct ieee80211vap *vap = ni->ni_vap;
851 	uint8_t tid;
852 #endif
853 
854 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
855 
856 #ifdef IEEE80211_AMPDU_AGE
857 	for (tid = 0; tid < WME_NUM_TID; tid++) {
858 		struct ieee80211_rx_ampdu *rap;
859 
860 		rap = &ni->ni_rx_ampdu[tid];
861 		if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0)
862 			continue;
863 		if (rap->rxa_qframes == 0)
864 			continue;
865 		/*
866 		 * Check for frames sitting too long in the reorder queue.
867 		 * See above for more details on what's happening here.
868 		 */
869 		/* XXX honor batimeout? */
870 		if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
871 			/*
872 			 * Too long since we received the first
873 			 * frame; flush the reorder buffer.
874 			 */
875 			vap->iv_stats.is_ampdu_rx_age += rap->rxa_qframes;
876 			ampdu_rx_flush(ni, rap);
877 		}
878 	}
879 #endif /* IEEE80211_AMPDU_AGE */
880 }
881 
882 static struct ieee80211_channel *
883 findhtchan(struct ieee80211com *ic, struct ieee80211_channel *c, int htflags)
884 {
885 	return ieee80211_find_channel(ic, c->ic_freq,
886 	    (c->ic_flags &~ IEEE80211_CHAN_HT) | htflags);
887 }
888 
889 /*
890  * Adjust a channel to be HT/non-HT according to the vap's configuration.
891  */
892 struct ieee80211_channel *
893 ieee80211_ht_adjust_channel(struct ieee80211com *ic,
894 	struct ieee80211_channel *chan, int flags)
895 {
896 	struct ieee80211_channel *c;
897 
898 	if (flags & IEEE80211_FEXT_HT) {
899 		/* promote to HT if possible */
900 		if (flags & IEEE80211_FEXT_USEHT40) {
901 			if (!IEEE80211_IS_CHAN_HT40(chan)) {
902 				/* NB: arbitrarily pick ht40+ over ht40- */
903 				c = findhtchan(ic, chan, IEEE80211_CHAN_HT40U);
904 				if (c == NULL)
905 					c = findhtchan(ic, chan,
906 						IEEE80211_CHAN_HT40D);
907 				if (c == NULL)
908 					c = findhtchan(ic, chan,
909 						IEEE80211_CHAN_HT20);
910 				if (c != NULL)
911 					chan = c;
912 			}
913 		} else if (!IEEE80211_IS_CHAN_HT20(chan)) {
914 			c = findhtchan(ic, chan, IEEE80211_CHAN_HT20);
915 			if (c != NULL)
916 				chan = c;
917 		}
918 	} else if (IEEE80211_IS_CHAN_HT(chan)) {
919 		/* demote to legacy, HT use is disabled */
920 		c = ieee80211_find_channel(ic, chan->ic_freq,
921 		    chan->ic_flags &~ IEEE80211_CHAN_HT);
922 		if (c != NULL)
923 			chan = c;
924 	}
925 	return chan;
926 }
927 
928 /*
929  * Setup HT-specific state for a legacy WDS peer.
930  */
931 void
932 ieee80211_ht_wds_init(struct ieee80211_node *ni)
933 {
934 	struct ieee80211vap *vap = ni->ni_vap;
935 	struct ieee80211_tx_ampdu *tap;
936 	int ac;
937 
938 	KASSERT(vap->iv_flags_ext & IEEE80211_FEXT_HT, ("no HT requested"));
939 
940 	/* XXX check scan cache in case peer has an ap and we have info */
941 	/*
942 	 * If setup with a legacy channel; locate an HT channel.
943 	 * Otherwise if the inherited channel (from a companion
944 	 * AP) is suitable use it so we use the same location
945 	 * for the extension channel).
946 	 */
947 	ni->ni_chan = ieee80211_ht_adjust_channel(ni->ni_ic,
948 	    ni->ni_chan, ieee80211_htchanflags(ni->ni_chan));
949 
950 	ni->ni_htcap = 0;
951 	if (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI20)
952 		ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI20;
953 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan)) {
954 		ni->ni_htcap |= IEEE80211_HTCAP_CHWIDTH40;
955 		ni->ni_chw = 40;
956 		if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
957 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_ABOVE;
958 		else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
959 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_BELOW;
960 		if (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI40)
961 			ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI40;
962 	} else {
963 		ni->ni_chw = 20;
964 		ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_NONE;
965 	}
966 	ni->ni_htctlchan = ni->ni_chan->ic_ieee;
967 	if (vap->iv_flags_ext & IEEE80211_FEXT_RIFS)
968 		ni->ni_flags |= IEEE80211_NODE_RIFS;
969 	/* XXX does it make sense to enable SMPS? */
970 
971 	ni->ni_htopmode = 0;		/* XXX need protection state */
972 	ni->ni_htstbc = 0;		/* XXX need info */
973 
974 	for (ac = 0; ac < WME_NUM_AC; ac++) {
975 		tap = &ni->ni_tx_ampdu[ac];
976 		tap->txa_ac = ac;
977 	}
978 	/* NB: AMPDU tx/rx governed by IEEE80211_FEXT_AMPDU_{TX,RX} */
979 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
980 }
981 
982 /*
983  * Notify hostap vaps of a change in the HTINFO ie.
984  */
985 static void
986 htinfo_notify(struct ieee80211com *ic)
987 {
988 	struct ieee80211vap *vap;
989 	int first = 1;
990 
991 	IEEE80211_LOCK_ASSERT(ic);
992 
993 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
994 		if (vap->iv_opmode != IEEE80211_M_HOSTAP)
995 			continue;
996 		if (vap->iv_state != IEEE80211_S_RUN ||
997 		    !IEEE80211_IS_CHAN_HT(vap->iv_bss->ni_chan))
998 			continue;
999 		if (first) {
1000 			IEEE80211_NOTE(vap,
1001 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1002 			    vap->iv_bss,
1003 			    "HT bss occupancy change: %d sta, %d ht, "
1004 			    "%d ht40%s, HT protmode now 0x%x"
1005 			    , ic->ic_sta_assoc
1006 			    , ic->ic_ht_sta_assoc
1007 			    , ic->ic_ht40_sta_assoc
1008 			    , (ic->ic_flags_ext & IEEE80211_FEXT_NONHT_PR) ?
1009 				 ", non-HT sta present" : ""
1010 			    , ic->ic_curhtprotmode);
1011 			first = 0;
1012 		}
1013 		ieee80211_beacon_notify(vap, IEEE80211_BEACON_HTINFO);
1014 	}
1015 }
1016 
1017 /*
1018  * Calculate HT protection mode from current
1019  * state and handle updates.
1020  */
1021 static void
1022 htinfo_update(struct ieee80211com *ic)
1023 {
1024 	uint8_t protmode;
1025 
1026 	if (ic->ic_sta_assoc != ic->ic_ht_sta_assoc) {
1027 		protmode = IEEE80211_HTINFO_OPMODE_MIXED
1028 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1029 	} else if (ic->ic_flags_ext & IEEE80211_FEXT_NONHT_PR) {
1030 		protmode = IEEE80211_HTINFO_OPMODE_PROTOPT
1031 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1032 	} else if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
1033 	    IEEE80211_IS_CHAN_HT40(ic->ic_bsschan) &&
1034 	    ic->ic_sta_assoc != ic->ic_ht40_sta_assoc) {
1035 		protmode = IEEE80211_HTINFO_OPMODE_HT20PR;
1036 	} else {
1037 		protmode = IEEE80211_HTINFO_OPMODE_PURE;
1038 	}
1039 	if (protmode != ic->ic_curhtprotmode) {
1040 		ic->ic_curhtprotmode = protmode;
1041 		htinfo_notify(ic);
1042 	}
1043 }
1044 
1045 /*
1046  * Handle an HT station joining a BSS.
1047  */
1048 void
1049 ieee80211_ht_node_join(struct ieee80211_node *ni)
1050 {
1051 	struct ieee80211com *ic = ni->ni_ic;
1052 
1053 	IEEE80211_LOCK_ASSERT(ic);
1054 
1055 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1056 		ic->ic_ht_sta_assoc++;
1057 		if (ni->ni_chw == 40)
1058 			ic->ic_ht40_sta_assoc++;
1059 	}
1060 	htinfo_update(ic);
1061 }
1062 
1063 /*
1064  * Handle an HT station leaving a BSS.
1065  */
1066 void
1067 ieee80211_ht_node_leave(struct ieee80211_node *ni)
1068 {
1069 	struct ieee80211com *ic = ni->ni_ic;
1070 
1071 	IEEE80211_LOCK_ASSERT(ic);
1072 
1073 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1074 		ic->ic_ht_sta_assoc--;
1075 		if (ni->ni_chw == 40)
1076 			ic->ic_ht40_sta_assoc--;
1077 	}
1078 	htinfo_update(ic);
1079 }
1080 
1081 /*
1082  * Public version of htinfo_update; used for processing
1083  * beacon frames from overlapping bss.
1084  *
1085  * Caller can specify either IEEE80211_HTINFO_OPMODE_MIXED
1086  * (on receipt of a beacon that advertises MIXED) or
1087  * IEEE80211_HTINFO_OPMODE_PROTOPT (on receipt of a beacon
1088  * from an overlapping legacy bss).  We treat MIXED with
1089  * a higher precedence than PROTOPT (i.e. we will not change
1090  * change PROTOPT -> MIXED; only MIXED -> PROTOPT).  This
1091  * corresponds to how we handle things in htinfo_update.
1092  */
1093 void
1094 ieee80211_htprot_update(struct ieee80211com *ic, int protmode)
1095 {
1096 #define	OPMODE(x)	SM(x, IEEE80211_HTINFO_OPMODE)
1097 	IEEE80211_LOCK(ic);
1098 
1099 	/* track non-HT station presence */
1100 	KASSERT(protmode & IEEE80211_HTINFO_NONHT_PRESENT,
1101 	    ("protmode 0x%x", protmode));
1102 	ic->ic_flags_ext |= IEEE80211_FEXT_NONHT_PR;
1103 	ic->ic_lastnonht = ticks;
1104 
1105 	if (protmode != ic->ic_curhtprotmode &&
1106 	    (OPMODE(ic->ic_curhtprotmode) != IEEE80211_HTINFO_OPMODE_MIXED ||
1107 	     OPMODE(protmode) == IEEE80211_HTINFO_OPMODE_PROTOPT)) {
1108 		/* push beacon update */
1109 		ic->ic_curhtprotmode = protmode;
1110 		htinfo_notify(ic);
1111 	}
1112 	IEEE80211_UNLOCK(ic);
1113 #undef OPMODE
1114 }
1115 
1116 /*
1117  * Time out presence of an overlapping bss with non-HT
1118  * stations.  When operating in hostap mode we listen for
1119  * beacons from other stations and if we identify a non-HT
1120  * station is present we update the opmode field of the
1121  * HTINFO ie.  To identify when all non-HT stations are
1122  * gone we time out this condition.
1123  */
1124 void
1125 ieee80211_ht_timeout(struct ieee80211com *ic)
1126 {
1127 	IEEE80211_LOCK_ASSERT(ic);
1128 
1129 	if ((ic->ic_flags_ext & IEEE80211_FEXT_NONHT_PR) &&
1130 	    time_after(ticks, ic->ic_lastnonht + IEEE80211_NONHT_PRESENT_AGE)) {
1131 #if 0
1132 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1133 		    "%s", "time out non-HT STA present on channel");
1134 #endif
1135 		ic->ic_flags_ext &= ~IEEE80211_FEXT_NONHT_PR;
1136 		htinfo_update(ic);
1137 	}
1138 }
1139 
1140 /* unalligned little endian access */
1141 #define LE_READ_2(p)					\
1142 	((uint16_t)					\
1143 	 ((((const uint8_t *)(p))[0]      ) |		\
1144 	  (((const uint8_t *)(p))[1] <<  8)))
1145 
1146 /*
1147  * Process an 802.11n HT capabilities ie.
1148  */
1149 void
1150 ieee80211_parse_htcap(struct ieee80211_node *ni, const uint8_t *ie)
1151 {
1152 	if (ie[0] == IEEE80211_ELEMID_VENDOR) {
1153 		/*
1154 		 * Station used Vendor OUI ie to associate;
1155 		 * mark the node so when we respond we'll use
1156 		 * the Vendor OUI's and not the standard ie's.
1157 		 */
1158 		ni->ni_flags |= IEEE80211_NODE_HTCOMPAT;
1159 		ie += 4;
1160 	} else
1161 		ni->ni_flags &= ~IEEE80211_NODE_HTCOMPAT;
1162 
1163 	ni->ni_htcap = LE_READ_2(ie +
1164 		__offsetof(struct ieee80211_ie_htcap, hc_cap));
1165 	ni->ni_htparam = ie[__offsetof(struct ieee80211_ie_htcap, hc_param)];
1166 }
1167 
1168 static void
1169 htinfo_parse(struct ieee80211_node *ni,
1170 	const struct ieee80211_ie_htinfo *htinfo)
1171 {
1172 	uint16_t w;
1173 
1174 	ni->ni_htctlchan = htinfo->hi_ctrlchannel;
1175 	ni->ni_ht2ndchan = SM(htinfo->hi_byte1, IEEE80211_HTINFO_2NDCHAN);
1176 	w = LE_READ_2(&htinfo->hi_byte2);
1177 	ni->ni_htopmode = SM(w, IEEE80211_HTINFO_OPMODE);
1178 	w = LE_READ_2(&htinfo->hi_byte45);
1179 	ni->ni_htstbc = SM(w, IEEE80211_HTINFO_BASIC_STBCMCS);
1180 }
1181 
1182 /*
1183  * Parse an 802.11n HT info ie and save useful information
1184  * to the node state.  Note this does not effect any state
1185  * changes such as for channel width change.
1186  */
1187 void
1188 ieee80211_parse_htinfo(struct ieee80211_node *ni, const uint8_t *ie)
1189 {
1190 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1191 		ie += 4;
1192 	htinfo_parse(ni, (const struct ieee80211_ie_htinfo *) ie);
1193 }
1194 
1195 /*
1196  * Handle 11n channel switch.  Use the received HT ie's to
1197  * identify the right channel to use.  If we cannot locate it
1198  * in the channel table then fallback to legacy operation.
1199  * Note that we use this information to identify the node's
1200  * channel only; the caller is responsible for insuring any
1201  * required channel change is done (e.g. in sta mode when
1202  * parsing the contents of a beacon frame).
1203  */
1204 static void
1205 htinfo_update_chw(struct ieee80211_node *ni, int htflags)
1206 {
1207 	struct ieee80211com *ic = ni->ni_ic;
1208 	struct ieee80211_channel *c;
1209 	int chanflags;
1210 
1211 	chanflags = (ni->ni_chan->ic_flags &~ IEEE80211_CHAN_HT) | htflags;
1212 	if (chanflags != ni->ni_chan->ic_flags) {
1213 		/* XXX not right for ht40- */
1214 		c = ieee80211_find_channel(ic, ni->ni_chan->ic_freq, chanflags);
1215 		if (c == NULL && (htflags & IEEE80211_CHAN_HT40)) {
1216 			/*
1217 			 * No HT40 channel entry in our table; fall back
1218 			 * to HT20 operation.  This should not happen.
1219 			 */
1220 			c = findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT20);
1221 #if 0
1222 			IEEE80211_NOTE(ni->ni_vap,
1223 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1224 			    "no HT40 channel (freq %u), falling back to HT20",
1225 			    ni->ni_chan->ic_freq);
1226 #endif
1227 			/* XXX stat */
1228 		}
1229 		if (c != NULL && c != ni->ni_chan) {
1230 			IEEE80211_NOTE(ni->ni_vap,
1231 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1232 			    "switch station to HT%d channel %u/0x%x",
1233 			    IEEE80211_IS_CHAN_HT40(c) ? 40 : 20,
1234 			    c->ic_freq, c->ic_flags);
1235 			ni->ni_chan = c;
1236 		}
1237 		/* NB: caller responsible for forcing any channel change */
1238 	}
1239 	/* update node's tx channel width */
1240 	ni->ni_chw = IEEE80211_IS_CHAN_HT40(ni->ni_chan)? 40 : 20;
1241 }
1242 
1243 /*
1244  * Update 11n MIMO PS state according to received htcap.
1245  */
1246 static __inline int
1247 htcap_update_mimo_ps(struct ieee80211_node *ni)
1248 {
1249 	uint16_t oflags = ni->ni_flags;
1250 
1251 	switch (ni->ni_htcap & IEEE80211_HTCAP_SMPS) {
1252 	case IEEE80211_HTCAP_SMPS_DYNAMIC:
1253 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1254 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1255 		break;
1256 	case IEEE80211_HTCAP_SMPS_ENA:
1257 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1258 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1259 		break;
1260 	case IEEE80211_HTCAP_SMPS_OFF:
1261 	default:		/* disable on rx of reserved value */
1262 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1263 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1264 		break;
1265 	}
1266 	return (oflags ^ ni->ni_flags);
1267 }
1268 
1269 /*
1270  * Update short GI state according to received htcap
1271  * and local settings.
1272  */
1273 static __inline void
1274 htcap_update_shortgi(struct ieee80211_node *ni)
1275 {
1276 	struct ieee80211vap *vap = ni->ni_vap;
1277 
1278 	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
1279 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
1280 	    (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI20))
1281 		ni->ni_flags |= IEEE80211_NODE_SGI20;
1282 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
1283 	    (vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI40))
1284 		ni->ni_flags |= IEEE80211_NODE_SGI40;
1285 }
1286 
1287 /*
1288  * Parse and update HT-related state extracted from
1289  * the HT cap and info ie's.
1290  */
1291 void
1292 ieee80211_ht_updateparams(struct ieee80211_node *ni,
1293 	const uint8_t *htcapie, const uint8_t *htinfoie)
1294 {
1295 	struct ieee80211vap *vap = ni->ni_vap;
1296 	const struct ieee80211_ie_htinfo *htinfo;
1297 	int htflags;
1298 
1299 	ieee80211_parse_htcap(ni, htcapie);
1300 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1301 		htcap_update_mimo_ps(ni);
1302 	htcap_update_shortgi(ni);
1303 
1304 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
1305 		htinfoie += 4;
1306 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1307 	htinfo_parse(ni, htinfo);
1308 
1309 	htflags = (vap->iv_flags_ext & IEEE80211_FEXT_HT) ?
1310 	    IEEE80211_CHAN_HT20 : 0;
1311 	/* NB: honor operating mode constraint */
1312 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_TXWIDTH_2040) &&
1313 	    (vap->iv_flags_ext & IEEE80211_FEXT_USEHT40)) {
1314 		if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_ABOVE)
1315 			htflags = IEEE80211_CHAN_HT40U;
1316 		else if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_BELOW)
1317 			htflags = IEEE80211_CHAN_HT40D;
1318 	}
1319 	htinfo_update_chw(ni, htflags);
1320 
1321 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_RIFSMODE_PERM) &&
1322 	    (vap->iv_flags_ext & IEEE80211_FEXT_RIFS))
1323 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1324 	else
1325 		ni->ni_flags &= ~IEEE80211_NODE_RIFS;
1326 }
1327 
1328 /*
1329  * Parse and update HT-related state extracted from the HT cap ie
1330  * for a station joining an HT BSS.
1331  */
1332 void
1333 ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
1334 {
1335 	struct ieee80211vap *vap = ni->ni_vap;
1336 	int htflags;
1337 
1338 	ieee80211_parse_htcap(ni, htcapie);
1339 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1340 		htcap_update_mimo_ps(ni);
1341 	htcap_update_shortgi(ni);
1342 
1343 	/* NB: honor operating mode constraint */
1344 	/* XXX 40 MHZ intolerant */
1345 	htflags = (vap->iv_flags_ext & IEEE80211_FEXT_HT) ?
1346 	    IEEE80211_CHAN_HT20 : 0;
1347 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) &&
1348 	    (vap->iv_flags_ext & IEEE80211_FEXT_USEHT40)) {
1349 		if (IEEE80211_IS_CHAN_HT40U(vap->iv_bss->ni_chan))
1350 			htflags = IEEE80211_CHAN_HT40U;
1351 		else if (IEEE80211_IS_CHAN_HT40D(vap->iv_bss->ni_chan))
1352 			htflags = IEEE80211_CHAN_HT40D;
1353 	}
1354 	htinfo_update_chw(ni, htflags);
1355 }
1356 
1357 /*
1358  * Install received HT rate set by parsing the HT cap ie.
1359  */
1360 int
1361 ieee80211_setup_htrates(struct ieee80211_node *ni, const uint8_t *ie, int flags)
1362 {
1363 	struct ieee80211vap *vap = ni->ni_vap;
1364 	const struct ieee80211_ie_htcap *htcap;
1365 	struct ieee80211_htrateset *rs;
1366 	int i;
1367 
1368 	rs = &ni->ni_htrates;
1369 	memset(rs, 0, sizeof(*rs));
1370 	if (ie != NULL) {
1371 		if (ie[0] == IEEE80211_ELEMID_VENDOR)
1372 			ie += 4;
1373 		htcap = (const struct ieee80211_ie_htcap *) ie;
1374 		for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1375 			if (isclr(htcap->hc_mcsset, i))
1376 				continue;
1377 			if (rs->rs_nrates == IEEE80211_HTRATE_MAXSIZE) {
1378 				IEEE80211_NOTE(vap,
1379 				    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1380 				    "WARNING, HT rate set too large; only "
1381 				    "using %u rates", IEEE80211_HTRATE_MAXSIZE);
1382 				vap->iv_stats.is_rx_rstoobig++;
1383 				break;
1384 			}
1385 			rs->rs_rates[rs->rs_nrates++] = i;
1386 		}
1387 	}
1388 	return ieee80211_fix_rate(ni, (struct ieee80211_rateset *) rs, flags);
1389 }
1390 
1391 /*
1392  * Mark rates in a node's HT rate set as basic according
1393  * to the information in the supplied HT info ie.
1394  */
1395 void
1396 ieee80211_setup_basic_htrates(struct ieee80211_node *ni, const uint8_t *ie)
1397 {
1398 	const struct ieee80211_ie_htinfo *htinfo;
1399 	struct ieee80211_htrateset *rs;
1400 	int i, j;
1401 
1402 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1403 		ie += 4;
1404 	htinfo = (const struct ieee80211_ie_htinfo *) ie;
1405 	rs = &ni->ni_htrates;
1406 	if (rs->rs_nrates == 0) {
1407 		IEEE80211_NOTE(ni->ni_vap,
1408 		    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1409 		    "%s", "WARNING, empty HT rate set");
1410 		return;
1411 	}
1412 	for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1413 		if (isclr(htinfo->hi_basicmcsset, i))
1414 			continue;
1415 		for (j = 0; j < rs->rs_nrates; j++)
1416 			if ((rs->rs_rates[j] & IEEE80211_RATE_VAL) == i)
1417 				rs->rs_rates[j] |= IEEE80211_RATE_BASIC;
1418 	}
1419 }
1420 
1421 static void
1422 ampdu_tx_setup(struct ieee80211_tx_ampdu *tap)
1423 {
1424 	callout_init(&tap->txa_timer, CALLOUT_MPSAFE);
1425 	tap->txa_flags |= IEEE80211_AGGR_SETUP;
1426 }
1427 
1428 static void
1429 ampdu_tx_stop(struct ieee80211_tx_ampdu *tap)
1430 {
1431 	struct ieee80211_node *ni = tap->txa_ni;
1432 	struct ieee80211com *ic = ni->ni_ic;
1433 
1434 	KASSERT(tap->txa_flags & IEEE80211_AGGR_SETUP,
1435 	    ("txa_flags 0x%x ac %d", tap->txa_flags, tap->txa_ac));
1436 
1437 	/*
1438 	 * Stop BA stream if setup so driver has a chance
1439 	 * to reclaim any resources it might have allocated.
1440 	 */
1441 	ic->ic_addba_stop(ni, tap);
1442 	/*
1443 	 * Stop any pending BAR transmit.
1444 	 */
1445 	bar_stop_timer(tap);
1446 
1447 	tap->txa_lastsample = 0;
1448 	tap->txa_avgpps = 0;
1449 	/* NB: clearing NAK means we may re-send ADDBA */
1450 	tap->txa_flags &= ~(IEEE80211_AGGR_SETUP | IEEE80211_AGGR_NAK);
1451 }
1452 
1453 static void
1454 addba_timeout(void *arg)
1455 {
1456 	struct ieee80211_tx_ampdu *tap = arg;
1457 
1458 	/* XXX ? */
1459 	tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1460 	tap->txa_attempts++;
1461 }
1462 
1463 static void
1464 addba_start_timeout(struct ieee80211_tx_ampdu *tap)
1465 {
1466 	/* XXX use CALLOUT_PENDING instead? */
1467 	callout_reset(&tap->txa_timer, ieee80211_addba_timeout,
1468 	    addba_timeout, tap);
1469 	tap->txa_flags |= IEEE80211_AGGR_XCHGPEND;
1470 	tap->txa_nextrequest = ticks + ieee80211_addba_timeout;
1471 }
1472 
1473 static void
1474 addba_stop_timeout(struct ieee80211_tx_ampdu *tap)
1475 {
1476 	/* XXX use CALLOUT_PENDING instead? */
1477 	if (tap->txa_flags & IEEE80211_AGGR_XCHGPEND) {
1478 		callout_stop(&tap->txa_timer);
1479 		tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1480 	}
1481 }
1482 
1483 /*
1484  * Default method for requesting A-MPDU tx aggregation.
1485  * We setup the specified state block and start a timer
1486  * to wait for an ADDBA response frame.
1487  */
1488 static int
1489 ieee80211_addba_request(struct ieee80211_node *ni,
1490 	struct ieee80211_tx_ampdu *tap,
1491 	int dialogtoken, int baparamset, int batimeout)
1492 {
1493 	int bufsiz;
1494 
1495 	/* XXX locking */
1496 	tap->txa_token = dialogtoken;
1497 	tap->txa_flags |= IEEE80211_AGGR_IMMEDIATE;
1498 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1499 	tap->txa_wnd = (bufsiz == 0) ?
1500 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1501 	addba_start_timeout(tap);
1502 	return 1;
1503 }
1504 
1505 /*
1506  * Default method for processing an A-MPDU tx aggregation
1507  * response.  We shutdown any pending timer and update the
1508  * state block according to the reply.
1509  */
1510 static int
1511 ieee80211_addba_response(struct ieee80211_node *ni,
1512 	struct ieee80211_tx_ampdu *tap,
1513 	int status, int baparamset, int batimeout)
1514 {
1515 	int bufsiz, tid;
1516 
1517 	/* XXX locking */
1518 	addba_stop_timeout(tap);
1519 	if (status == IEEE80211_STATUS_SUCCESS) {
1520 		bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1521 		/* XXX override our request? */
1522 		tap->txa_wnd = (bufsiz == 0) ?
1523 		    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1524 		/* XXX AC/TID */
1525 		tid = MS(baparamset, IEEE80211_BAPS_TID);
1526 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
1527 		tap->txa_attempts = 0;
1528 	} else {
1529 		/* mark tid so we don't try again */
1530 		tap->txa_flags |= IEEE80211_AGGR_NAK;
1531 	}
1532 	return 1;
1533 }
1534 
1535 /*
1536  * Default method for stopping A-MPDU tx aggregation.
1537  * Any timer is cleared and we drain any pending frames.
1538  */
1539 static void
1540 ieee80211_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
1541 {
1542 	/* XXX locking */
1543 	addba_stop_timeout(tap);
1544 	if (tap->txa_flags & IEEE80211_AGGR_RUNNING) {
1545 		/* XXX clear aggregation queue */
1546 		tap->txa_flags &= ~IEEE80211_AGGR_RUNNING;
1547 	}
1548 	tap->txa_attempts = 0;
1549 }
1550 
1551 /*
1552  * Process a received action frame using the default aggregation
1553  * policy.  We intercept ADDBA-related frames and use them to
1554  * update our aggregation state.  All other frames are passed up
1555  * for processing by ieee80211_recv_action.
1556  */
1557 static void
1558 ieee80211_aggr_recv_action(struct ieee80211_node *ni,
1559 	const uint8_t *frm, const uint8_t *efrm)
1560 {
1561 	struct ieee80211com *ic = ni->ni_ic;
1562 	struct ieee80211vap *vap = ni->ni_vap;
1563 	const struct ieee80211_action *ia;
1564 	struct ieee80211_rx_ampdu *rap;
1565 	struct ieee80211_tx_ampdu *tap;
1566 	uint8_t dialogtoken, policy;
1567 	uint16_t baparamset, batimeout, baseqctl, code;
1568 	uint16_t args[4];
1569 	int tid, ac, bufsiz;
1570 
1571 	ia = (const struct ieee80211_action *) frm;
1572 	switch (ia->ia_category) {
1573 	case IEEE80211_ACTION_CAT_BA:
1574 		switch (ia->ia_action) {
1575 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
1576 			dialogtoken = frm[2];
1577 			baparamset = LE_READ_2(frm+3);
1578 			batimeout = LE_READ_2(frm+5);
1579 			baseqctl = LE_READ_2(frm+7);
1580 
1581 			tid = MS(baparamset, IEEE80211_BAPS_TID);
1582 			bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1583 
1584 			IEEE80211_NOTE(vap,
1585 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1586 			    "recv ADDBA request: dialogtoken %u "
1587 			    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d "
1588 			    "baseqctl %d:%d",
1589 			    dialogtoken, baparamset, tid, bufsiz, batimeout,
1590 			    MS(baseqctl, IEEE80211_BASEQ_START),
1591 			    MS(baseqctl, IEEE80211_BASEQ_FRAG));
1592 
1593 			rap = &ni->ni_rx_ampdu[tid];
1594 
1595 			/* Send ADDBA response */
1596 			args[0] = dialogtoken;
1597 			/*
1598 			 * NB: We ack only if the sta associated with HT and
1599 			 * the ap is configured to do AMPDU rx (the latter
1600 			 * violates the 11n spec and is mostly for testing).
1601 			 */
1602 			if ((ni->ni_flags & IEEE80211_NODE_AMPDU_RX) &&
1603 			    (vap->iv_flags_ext & IEEE80211_FEXT_AMPDU_RX)) {
1604 				ampdu_rx_start(rap, bufsiz,
1605 				    MS(baseqctl, IEEE80211_BASEQ_START));
1606 
1607 				args[1] = IEEE80211_STATUS_SUCCESS;
1608 			} else {
1609 				IEEE80211_NOTE(vap,
1610 				    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1611 				    ni, "reject ADDBA request: %s",
1612 				    ni->ni_flags & IEEE80211_NODE_AMPDU_RX ?
1613 				       "administratively disabled" :
1614 				       "not negotiated for station");
1615 				vap->iv_stats.is_addba_reject++;
1616 				args[1] = IEEE80211_STATUS_UNSPECIFIED;
1617 			}
1618 			/* XXX honor rap flags? */
1619 			args[2] = IEEE80211_BAPS_POLICY_IMMEDIATE
1620 				| SM(tid, IEEE80211_BAPS_TID)
1621 				| SM(rap->rxa_wnd, IEEE80211_BAPS_BUFSIZ)
1622 				;
1623 			args[3] = 0;
1624 			ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1625 				IEEE80211_ACTION_BA_ADDBA_RESPONSE, args);
1626 			return;
1627 
1628 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
1629 			dialogtoken = frm[2];
1630 			code = LE_READ_2(frm+3);
1631 			baparamset = LE_READ_2(frm+5);
1632 			tid = MS(baparamset, IEEE80211_BAPS_TID);
1633 			bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1634 			policy = MS(baparamset, IEEE80211_BAPS_POLICY);
1635 			batimeout = LE_READ_2(frm+7);
1636 
1637 			ac = TID_TO_WME_AC(tid);
1638 			tap = &ni->ni_tx_ampdu[ac];
1639 			if ((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
1640 				IEEE80211_DISCARD_MAC(vap,
1641 				    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1642 				    ni->ni_macaddr, "ADDBA response",
1643 				    "no pending ADDBA, tid %d dialogtoken %u "
1644 				    "code %d", tid, dialogtoken, code);
1645 				vap->iv_stats.is_addba_norequest++;
1646 				return;
1647 			}
1648 			if (dialogtoken != tap->txa_token) {
1649 				IEEE80211_DISCARD_MAC(vap,
1650 				    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1651 				    ni->ni_macaddr, "ADDBA response",
1652 				    "dialogtoken mismatch: waiting for %d, "
1653 				    "received %d, tid %d code %d",
1654 				    tap->txa_token, dialogtoken, tid, code);
1655 				vap->iv_stats.is_addba_badtoken++;
1656 				return;
1657 			}
1658 			/* NB: assumes IEEE80211_AGGR_IMMEDIATE is 1 */
1659 			if (policy != (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE)) {
1660 				IEEE80211_DISCARD_MAC(vap,
1661 				    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1662 				    ni->ni_macaddr, "ADDBA response",
1663 				    "policy mismatch: expecting %s, "
1664 				    "received %s, tid %d code %d",
1665 				    tap->txa_flags & IEEE80211_AGGR_IMMEDIATE,
1666 				    policy, tid, code);
1667 				vap->iv_stats.is_addba_badpolicy++;
1668 				return;
1669 			}
1670 #if 0
1671 			/* XXX we take MIN in ieee80211_addba_response */
1672 			if (bufsiz > IEEE80211_AGGR_BAWMAX) {
1673 				IEEE80211_DISCARD_MAC(vap,
1674 				    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1675 				    ni->ni_macaddr, "ADDBA response",
1676 				    "BA window too large: max %d, "
1677 				    "received %d, tid %d code %d",
1678 				    bufsiz, IEEE80211_AGGR_BAWMAX, tid, code);
1679 				vap->iv_stats.is_addba_badbawinsize++;
1680 				return;
1681 			}
1682 #endif
1683 			IEEE80211_NOTE(vap,
1684 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1685 			    "recv ADDBA response: dialogtoken %u code %d "
1686 			    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d",
1687 			    dialogtoken, code, baparamset, tid, bufsiz,
1688 			    batimeout);
1689 			ic->ic_addba_response(ni, tap,
1690 				code, baparamset, batimeout);
1691 			return;
1692 
1693 		case IEEE80211_ACTION_BA_DELBA:
1694 			baparamset = LE_READ_2(frm+2);
1695 			code = LE_READ_2(frm+4);
1696 
1697 			tid = MS(baparamset, IEEE80211_DELBAPS_TID);
1698 
1699 			IEEE80211_NOTE(vap,
1700 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1701 			    "recv DELBA: baparamset 0x%x (tid %d initiator %d) "
1702 			    "code %d", baparamset, tid,
1703 			    MS(baparamset, IEEE80211_DELBAPS_INIT), code);
1704 
1705 			if ((baparamset & IEEE80211_DELBAPS_INIT) == 0) {
1706 				ac = TID_TO_WME_AC(tid);
1707 				tap = &ni->ni_tx_ampdu[ac];
1708 				ic->ic_addba_stop(ni, tap);
1709 			} else {
1710 				rap = &ni->ni_rx_ampdu[tid];
1711 				ampdu_rx_stop(rap);
1712 			}
1713 			return;
1714 		}
1715 		break;
1716 	}
1717 	ieee80211_recv_action(ni, frm, efrm);
1718 }
1719 
1720 /*
1721  * Process a received 802.11n action frame.
1722  * Aggregation-related frames are assumed to be handled
1723  * already; we handle any other frames we can, otherwise
1724  * complain about being unsupported (with debugging).
1725  */
1726 void
1727 ieee80211_recv_action(struct ieee80211_node *ni,
1728 	const uint8_t *frm, const uint8_t *efrm)
1729 {
1730 	struct ieee80211vap *vap = ni->ni_vap;
1731 	const struct ieee80211_action *ia;
1732 	int chw;
1733 
1734 	ia = (const struct ieee80211_action *) frm;
1735 	switch (ia->ia_category) {
1736 	case IEEE80211_ACTION_CAT_BA:
1737 		IEEE80211_NOTE(vap,
1738 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1739 		    "%s: BA action %d not implemented", __func__,
1740 		    ia->ia_action);
1741 		vap->iv_stats.is_rx_mgtdiscard++;
1742 		break;
1743 	case IEEE80211_ACTION_CAT_HT:
1744 		switch (ia->ia_action) {
1745 		case IEEE80211_ACTION_HT_TXCHWIDTH:
1746 			chw = frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040 ? 40 : 20;
1747 			IEEE80211_NOTE(vap,
1748 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1749 		            "%s: HT txchwidth, width %d%s",
1750 			    __func__, chw, ni->ni_chw != chw ? "*" : "");
1751 			if (chw != ni->ni_chw) {
1752 				ni->ni_chw = chw;
1753 				/* XXX notify on change */
1754 			}
1755 			break;
1756 		case IEEE80211_ACTION_HT_MIMOPWRSAVE: {
1757 			const struct ieee80211_action_ht_mimopowersave *mps =
1758 			    (const struct ieee80211_action_ht_mimopowersave *) ia;
1759 			/* XXX check iv_htcaps */
1760 			if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_ENA)
1761 				ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1762 			else
1763 				ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1764 			if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_MODE)
1765 				ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1766 			else
1767 				ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1768 			/* XXX notify on change */
1769 			IEEE80211_NOTE(vap,
1770 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1771 		            "%s: HT MIMO PS (%s%s)", __func__,
1772 			    (ni->ni_flags & IEEE80211_NODE_MIMO_PS) ?
1773 				"on" : "off",
1774 			    (ni->ni_flags & IEEE80211_NODE_MIMO_RTS) ?
1775 				"+rts" : ""
1776 			);
1777 			break;
1778 		}
1779 		default:
1780 			IEEE80211_NOTE(vap,
1781 			   IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1782 		           "%s: HT action %d not implemented", __func__,
1783 			   ia->ia_action);
1784 			vap->iv_stats.is_rx_mgtdiscard++;
1785 			break;
1786 		}
1787 		break;
1788 	default:
1789 		IEEE80211_NOTE(vap,
1790 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1791 		    "%s: category %d not implemented", __func__,
1792 		    ia->ia_category);
1793 		vap->iv_stats.is_rx_mgtdiscard++;
1794 		break;
1795 	}
1796 }
1797 
1798 /*
1799  * Transmit processing.
1800  */
1801 
1802 /*
1803  * Check if A-MPDU should be requested/enabled for a stream.
1804  * We require a traffic rate above a per-AC threshold and we
1805  * also handle backoff from previous failed attempts.
1806  *
1807  * Drivers may override this method to bring in information
1808  * such as link state conditions in making the decision.
1809  */
1810 static int
1811 ieee80211_ampdu_enable(struct ieee80211_node *ni,
1812 	struct ieee80211_tx_ampdu *tap)
1813 {
1814 	struct ieee80211vap *vap = ni->ni_vap;
1815 
1816 	if (tap->txa_avgpps < vap->iv_ampdu_mintraffic[tap->txa_ac])
1817 		return 0;
1818 	/* XXX check rssi? */
1819 	if (tap->txa_attempts >= ieee80211_addba_maxtries &&
1820 	    ticks < tap->txa_nextrequest) {
1821 		/*
1822 		 * Don't retry too often; txa_nextrequest is set
1823 		 * to the minimum interval we'll retry after
1824 		 * ieee80211_addba_maxtries failed attempts are made.
1825 		 */
1826 		return 0;
1827 	}
1828 	IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1829 	    "enable AMPDU on %s, avgpps %d pkts %d",
1830 	    ieee80211_wme_acnames[tap->txa_ac], tap->txa_avgpps, tap->txa_pkts);
1831 	return 1;
1832 }
1833 
1834 /*
1835  * Request A-MPDU tx aggregation.  Setup local state and
1836  * issue an ADDBA request.  BA use will only happen after
1837  * the other end replies with ADDBA response.
1838  */
1839 int
1840 ieee80211_ampdu_request(struct ieee80211_node *ni,
1841 	struct ieee80211_tx_ampdu *tap)
1842 {
1843 	struct ieee80211com *ic = ni->ni_ic;
1844 	uint16_t args[4];
1845 	int tid, dialogtoken;
1846 	static int tokens = 0;	/* XXX */
1847 
1848 	/* XXX locking */
1849 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
1850 		/* do deferred setup of state */
1851 		ampdu_tx_setup(tap);
1852 	}
1853 	/* XXX hack for not doing proper locking */
1854 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
1855 
1856 	dialogtoken = (tokens+1) % 63;		/* XXX */
1857 	tid = WME_AC_TO_TID(tap->txa_ac);
1858 	tap->txa_start = ni->ni_txseqs[tid];
1859 
1860 	args[0] = dialogtoken;
1861 	args[1]	= IEEE80211_BAPS_POLICY_IMMEDIATE
1862 		| SM(tid, IEEE80211_BAPS_TID)
1863 		| SM(IEEE80211_AGGR_BAWMAX, IEEE80211_BAPS_BUFSIZ)
1864 		;
1865 	args[2] = 0;	/* batimeout */
1866 	/* NB: do first so there's no race against reply */
1867 	if (!ic->ic_addba_request(ni, tap, dialogtoken, args[1], args[2])) {
1868 		/* unable to setup state, don't make request */
1869 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1870 		    ni, "%s: could not setup BA stream for AC %d",
1871 		    __func__, tap->txa_ac);
1872 		/* defer next try so we don't slam the driver with requests */
1873 		tap->txa_attempts = ieee80211_addba_maxtries;
1874 		/* NB: check in case driver wants to override */
1875 		if (tap->txa_nextrequest <= ticks)
1876 			tap->txa_nextrequest = ticks + ieee80211_addba_backoff;
1877 		return 0;
1878 	}
1879 	tokens = dialogtoken;			/* allocate token */
1880 	/* NB: after calling ic_addba_request so driver can set txa_start */
1881 	args[3] = SM(tap->txa_start, IEEE80211_BASEQ_START)
1882 		| SM(0, IEEE80211_BASEQ_FRAG)
1883 		;
1884 	return ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1885 		IEEE80211_ACTION_BA_ADDBA_REQUEST, args);
1886 }
1887 
1888 /*
1889  * Terminate an AMPDU tx stream.  State is reclaimed
1890  * and the peer notified with a DelBA Action frame.
1891  */
1892 void
1893 ieee80211_ampdu_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
1894 	int reason)
1895 {
1896 	struct ieee80211com *ic = ni->ni_ic;
1897 	struct ieee80211vap *vap = ni->ni_vap;
1898 	uint16_t args[4];
1899 
1900 	/* XXX locking */
1901 	tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
1902 	if (IEEE80211_AMPDU_RUNNING(tap)) {
1903 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1904 		    ni, "%s: stop BA stream for AC %d (reason %d)",
1905 		    __func__, tap->txa_ac, reason);
1906 		vap->iv_stats.is_ampdu_stop++;
1907 
1908 		ic->ic_addba_stop(ni, tap);
1909 		args[0] = WME_AC_TO_TID(tap->txa_ac);
1910 		args[1] = IEEE80211_DELBAPS_INIT;
1911 		args[2] = reason;			/* XXX reason code */
1912 		ieee80211_send_action(ni, IEEE80211_ACTION_CAT_BA,
1913 			IEEE80211_ACTION_BA_DELBA, args);
1914 	} else {
1915 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1916 		    ni, "%s: BA stream for AC %d not running (reason %d)",
1917 		    __func__, tap->txa_ac, reason);
1918 		vap->iv_stats.is_ampdu_stop_failed++;
1919 	}
1920 }
1921 
1922 static void
1923 bar_timeout(void *arg)
1924 {
1925 	struct ieee80211_tx_ampdu *tap = arg;
1926 	struct ieee80211_node *ni = tap->txa_ni;
1927 
1928 	KASSERT((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0,
1929 	    ("bar/addba collision, flags 0x%x", tap->txa_flags));
1930 
1931 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1932 	    ni, "%s: tid %u flags 0x%x attempts %d", __func__,
1933 	    tap->txa_ac, tap->txa_flags, tap->txa_attempts);
1934 
1935 	/* guard against race with bar_tx_complete */
1936 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
1937 		return;
1938 	/* XXX ? */
1939 	if (tap->txa_attempts >= ieee80211_bar_maxtries)
1940 		ieee80211_ampdu_stop(ni, tap, IEEE80211_REASON_TIMEOUT);
1941 	else
1942 		ieee80211_send_bar(ni, tap, tap->txa_seqpending);
1943 }
1944 
1945 static void
1946 bar_start_timer(struct ieee80211_tx_ampdu *tap)
1947 {
1948 	callout_reset(&tap->txa_timer, ieee80211_bar_timeout, bar_timeout, tap);
1949 }
1950 
1951 static void
1952 bar_stop_timer(struct ieee80211_tx_ampdu *tap)
1953 {
1954 	callout_stop(&tap->txa_timer);
1955 }
1956 
1957 static void
1958 bar_tx_complete(struct ieee80211_node *ni, void *arg, int status)
1959 {
1960 	struct ieee80211_tx_ampdu *tap = arg;
1961 
1962 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1963 	    ni, "%s: tid %u flags 0x%x pending %d status %d",
1964 	    __func__, tap->txa_ac, tap->txa_flags,
1965 	    callout_pending(&tap->txa_timer), status);
1966 
1967 	/* XXX locking */
1968 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) &&
1969 	    callout_pending(&tap->txa_timer)) {
1970 		struct ieee80211com *ic = ni->ni_ic;
1971 
1972 		if (status)		/* ACK'd */
1973 			bar_stop_timer(tap);
1974 		ic->ic_bar_response(ni, tap, status);
1975 		/* NB: just let timer expire so we pace requests */
1976 	}
1977 }
1978 
1979 static void
1980 ieee80211_bar_response(struct ieee80211_node *ni,
1981 	struct ieee80211_tx_ampdu *tap, int status)
1982 {
1983 
1984 	if (status != 0) {		/* got ACK */
1985 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1986 		    ni, "BAR moves BA win <%u:%u> (%u frames) txseq %u tid %u",
1987 		    tap->txa_start,
1988 		    IEEE80211_SEQ_ADD(tap->txa_start, tap->txa_wnd-1),
1989 		    tap->txa_qframes, tap->txa_seqpending,
1990 		    WME_AC_TO_TID(tap->txa_ac));
1991 
1992 		/* NB: timer already stopped in bar_tx_complete */
1993 		tap->txa_start = tap->txa_seqpending;
1994 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
1995 	}
1996 }
1997 
1998 /*
1999  * Transmit a BAR frame to the specified node.  The
2000  * BAR contents are drawn from the supplied aggregation
2001  * state associated with the node.
2002  *
2003  * NB: we only handle immediate ACK w/ compressed bitmap.
2004  */
2005 int
2006 ieee80211_send_bar(struct ieee80211_node *ni,
2007 	struct ieee80211_tx_ampdu *tap, ieee80211_seq seq)
2008 {
2009 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2010 	struct ieee80211vap *vap = ni->ni_vap;
2011 	struct ieee80211com *ic = ni->ni_ic;
2012 	struct ieee80211_frame_bar *bar;
2013 	struct mbuf *m;
2014 	uint16_t barctl, barseqctl;
2015 	uint8_t *frm;
2016 	int tid, ret;
2017 
2018 	if ((tap->txa_flags & IEEE80211_AGGR_RUNNING) == 0) {
2019 		/* no ADDBA response, should not happen */
2020 		/* XXX stat+msg */
2021 		return EINVAL;
2022 	}
2023 	/* XXX locking */
2024 	bar_stop_timer(tap);
2025 
2026 	ieee80211_ref_node(ni);
2027 
2028 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom, sizeof(*bar));
2029 	if (m == NULL)
2030 		senderr(ENOMEM, is_tx_nobuf);
2031 
2032 	if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
2033 		m_freem(m);
2034 		senderr(ENOMEM, is_tx_nobuf);	/* XXX */
2035 		/* NOTREACHED */
2036 	}
2037 
2038 	bar = mtod(m, struct ieee80211_frame_bar *);
2039 	bar->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2040 		IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_BAR;
2041 	bar->i_fc[1] = 0;
2042 	IEEE80211_ADDR_COPY(bar->i_ra, ni->ni_macaddr);
2043 	IEEE80211_ADDR_COPY(bar->i_ta, vap->iv_myaddr);
2044 
2045 	tid = WME_AC_TO_TID(tap->txa_ac);
2046 	barctl 	= (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE ?
2047 			0 : IEEE80211_BAR_NOACK)
2048 		| IEEE80211_BAR_COMP
2049 		| SM(tid, IEEE80211_BAR_TID)
2050 		;
2051 	barseqctl = SM(seq, IEEE80211_BAR_SEQ_START);
2052 	/* NB: known to have proper alignment */
2053 	bar->i_ctl = htole16(barctl);
2054 	bar->i_seq = htole16(barseqctl);
2055 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_bar);
2056 
2057 	M_WME_SETAC(m, WME_AC_VO);
2058 
2059 	IEEE80211_NODE_STAT(ni, tx_mgmt);	/* XXX tx_ctl? */
2060 
2061 	/* XXX locking */
2062 	/* init/bump attempts counter */
2063 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2064 		tap->txa_attempts = 1;
2065 	else
2066 		tap->txa_attempts++;
2067 	tap->txa_seqpending = seq;
2068 	tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2069 
2070 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2071 	    ni, "send BAR: tid %u ctl 0x%x start %u (attempt %d)",
2072 	    tid, barctl, seq, tap->txa_attempts);
2073 
2074 	ret = ic->ic_raw_xmit(ni, m, NULL);
2075 	if (ret != 0) {
2076 		/* xmit failed, clear state flag */
2077 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2078 		goto bad;
2079 	}
2080 	/* XXX hack against tx complete happening before timer is started */
2081 	if (tap->txa_flags & IEEE80211_AGGR_BARPEND)
2082 		bar_start_timer(tap);
2083 	return 0;
2084 bad:
2085 	ieee80211_free_node(ni);
2086 	return ret;
2087 #undef senderr
2088 }
2089 
2090 /*
2091  * Send an action management frame.  The arguments are stuff
2092  * into a frame without inspection; the caller is assumed to
2093  * prepare them carefully (e.g. based on the aggregation state).
2094  */
2095 int
2096 ieee80211_send_action(struct ieee80211_node *ni,
2097 	int category, int action, uint16_t args[4])
2098 {
2099 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2100 #define	ADDSHORT(frm, v) do {			\
2101 	frm[0] = (v) & 0xff;			\
2102 	frm[1] = (v) >> 8;			\
2103 	frm += 2;				\
2104 } while (0)
2105 	struct ieee80211vap *vap = ni->ni_vap;
2106 	struct ieee80211com *ic = ni->ni_ic;
2107 	struct ieee80211_bpf_params params;
2108 	struct mbuf *m;
2109 	uint8_t *frm;
2110 	uint16_t baparamset;
2111 	int ret;
2112 
2113 	KASSERT(ni != NULL, ("null node"));
2114 
2115 	/*
2116 	 * Hold a reference on the node so it doesn't go away until after
2117 	 * the xmit is complete all the way in the driver.  On error we
2118 	 * will remove our reference.
2119 	 */
2120 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2121 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
2122 		__func__, __LINE__,
2123 		ni, ether_sprintf(ni->ni_macaddr),
2124 		ieee80211_node_refcnt(ni)+1);
2125 	ieee80211_ref_node(ni);
2126 
2127 	m = ieee80211_getmgtframe(&frm,
2128 		ic->ic_headroom + sizeof(struct ieee80211_frame),
2129 		  sizeof(uint16_t)	/* action+category */
2130 		/* XXX may action payload */
2131 		+ sizeof(struct ieee80211_action_ba_addbaresponse)
2132 	);
2133 	if (m == NULL)
2134 		senderr(ENOMEM, is_tx_nobuf);
2135 
2136 	*frm++ = category;
2137 	*frm++ = action;
2138 	switch (category) {
2139 	case IEEE80211_ACTION_CAT_BA:
2140 		switch (action) {
2141 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
2142 			IEEE80211_NOTE(vap,
2143 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2144 			    "send ADDBA request: dialogtoken %d "
2145 			    "baparamset 0x%x (tid %d) batimeout 0x%x baseqctl 0x%x",
2146 			    args[0], args[1], MS(args[1], IEEE80211_BAPS_TID),
2147 			    args[2], args[3]);
2148 
2149 			*frm++ = args[0];	/* dialog token */
2150 			ADDSHORT(frm, args[1]);	/* baparamset */
2151 			ADDSHORT(frm, args[2]);	/* batimeout */
2152 			ADDSHORT(frm, args[3]);	/* baseqctl */
2153 			break;
2154 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
2155 			IEEE80211_NOTE(vap,
2156 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2157 			    "send ADDBA response: dialogtoken %d status %d "
2158 			    "baparamset 0x%x (tid %d) batimeout %d",
2159 			    args[0], args[1], args[2],
2160 			    MS(args[2], IEEE80211_BAPS_TID), args[3]);
2161 
2162 			*frm++ = args[0];	/* dialog token */
2163 			ADDSHORT(frm, args[1]);	/* statuscode */
2164 			ADDSHORT(frm, args[2]);	/* baparamset */
2165 			ADDSHORT(frm, args[3]);	/* batimeout */
2166 			break;
2167 		case IEEE80211_ACTION_BA_DELBA:
2168 			/* XXX */
2169 			baparamset = SM(args[0], IEEE80211_DELBAPS_TID)
2170 				   | args[1]
2171 				   ;
2172 			ADDSHORT(frm, baparamset);
2173 			ADDSHORT(frm, args[2]);	/* reason code */
2174 
2175 			IEEE80211_NOTE(vap,
2176 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2177 			    "send DELBA action: tid %d, initiator %d reason %d",
2178 			    args[0], args[1], args[2]);
2179 			break;
2180 		default:
2181 			goto badaction;
2182 		}
2183 		break;
2184 	case IEEE80211_ACTION_CAT_HT:
2185 		switch (action) {
2186 		case IEEE80211_ACTION_HT_TXCHWIDTH:
2187 			IEEE80211_NOTE(vap,
2188 			    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2189 			    ni, "send HT txchwidth: width %d",
2190 			    IEEE80211_IS_CHAN_HT40(ni->ni_chan) ? 40 : 20
2191 			);
2192 			*frm++ = IEEE80211_IS_CHAN_HT40(ni->ni_chan) ?
2193 				IEEE80211_A_HT_TXCHWIDTH_2040 :
2194 				IEEE80211_A_HT_TXCHWIDTH_20;
2195 			break;
2196 		default:
2197 			goto badaction;
2198 		}
2199 		break;
2200 	default:
2201 	badaction:
2202 		IEEE80211_NOTE(vap,
2203 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2204 		    "%s: unsupported category %d action %d", __func__,
2205 		    category, action);
2206 		senderr(EINVAL, is_tx_unknownmgt);
2207 		/* NOTREACHED */
2208 	}
2209 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2210 
2211 	memset(&params, 0, sizeof(params));
2212 	params.ibp_pri = WME_AC_VO;
2213 	params.ibp_rate0 = ni->ni_txparms->mgmtrate;
2214 	/* NB: we know all frames are unicast */
2215 	params.ibp_try0 = ni->ni_txparms->maxretry;
2216 	params.ibp_power = ni->ni_txpower;
2217 	return ieee80211_mgmt_output(ni, m, IEEE80211_FC0_SUBTYPE_ACTION,
2218 	     &params);
2219 bad:
2220 	ieee80211_free_node(ni);
2221 	if (m != NULL)
2222 		m_freem(m);
2223 	return ret;
2224 #undef ADDSHORT
2225 #undef senderr
2226 }
2227 
2228 /*
2229  * Construct the MCS bit mask for inclusion
2230  * in an HT information element.
2231  */
2232 static void
2233 ieee80211_set_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2234 {
2235 	int i;
2236 
2237 	for (i = 0; i < rs->rs_nrates; i++) {
2238 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2239 		if (r < IEEE80211_HTRATE_MAXSIZE) {	/* XXX? */
2240 			/* NB: this assumes a particular implementation */
2241 			setbit(frm, r);
2242 		}
2243 	}
2244 }
2245 
2246 /*
2247  * Add body of an HTCAP information element.
2248  */
2249 static uint8_t *
2250 ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
2251 {
2252 #define	ADDSHORT(frm, v) do {			\
2253 	frm[0] = (v) & 0xff;			\
2254 	frm[1] = (v) >> 8;			\
2255 	frm += 2;				\
2256 } while (0)
2257 	struct ieee80211vap *vap = ni->ni_vap;
2258 	uint16_t caps;
2259 	int rxmax, density;
2260 
2261 	/* HT capabilities */
2262 	caps = vap->iv_htcaps & 0xffff;
2263 	/*
2264 	 * Note channel width depends on whether we are operating as
2265 	 * a sta or not.  When operating as a sta we are generating
2266 	 * a request based on our desired configuration.  Otherwise
2267 	 * we are operational and the channel attributes identify
2268 	 * how we've been setup (which might be different if a fixed
2269 	 * channel is specified).
2270 	 */
2271 	if (vap->iv_opmode == IEEE80211_M_STA) {
2272 		/* override 20/40 use based on config */
2273 		if (vap->iv_flags_ext & IEEE80211_FEXT_USEHT40)
2274 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2275 		else
2276 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2277 		/* use advertised setting (XXX locally constraint) */
2278 		rxmax = MS(ni->ni_htparam, IEEE80211_HTCAP_MAXRXAMPDU);
2279 		density = MS(ni->ni_htparam, IEEE80211_HTCAP_MPDUDENSITY);
2280 	} else {
2281 		/* override 20/40 use based on current channel */
2282 		if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2283 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2284 		else
2285 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2286 		rxmax = vap->iv_ampdu_rxmax;
2287 		density = vap->iv_ampdu_density;
2288 	}
2289 	/* adjust short GI based on channel and config */
2290 	if ((vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI20) == 0)
2291 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
2292 	if ((vap->iv_flags_ext & IEEE80211_FEXT_SHORTGI40) == 0 ||
2293 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
2294 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
2295 	ADDSHORT(frm, caps);
2296 
2297 	/* HT parameters */
2298 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
2299 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
2300 	     ;
2301 	frm++;
2302 
2303 	/* pre-zero remainder of ie */
2304 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
2305 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
2306 
2307 	/* supported MCS set */
2308 	/*
2309 	 * XXX it would better to get the rate set from ni_htrates
2310 	 * so we can restrict it but for sta mode ni_htrates isn't
2311 	 * setup when we're called to form an AssocReq frame so for
2312 	 * now we're restricted to the default HT rate set.
2313 	 */
2314 	ieee80211_set_htrates(frm, &ieee80211_rateset_11n);
2315 
2316 	frm += sizeof(struct ieee80211_ie_htcap) -
2317 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
2318 	return frm;
2319 #undef ADDSHORT
2320 }
2321 
2322 /*
2323  * Add 802.11n HT capabilities information element
2324  */
2325 uint8_t *
2326 ieee80211_add_htcap(uint8_t *frm, struct ieee80211_node *ni)
2327 {
2328 	frm[0] = IEEE80211_ELEMID_HTCAP;
2329 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
2330 	return ieee80211_add_htcap_body(frm + 2, ni);
2331 }
2332 
2333 /*
2334  * Add Broadcom OUI wrapped standard HTCAP ie; this is
2335  * used for compatibility w/ pre-draft implementations.
2336  */
2337 uint8_t *
2338 ieee80211_add_htcap_vendor(uint8_t *frm, struct ieee80211_node *ni)
2339 {
2340 	frm[0] = IEEE80211_ELEMID_VENDOR;
2341 	frm[1] = 4 + sizeof(struct ieee80211_ie_htcap) - 2;
2342 	frm[2] = (BCM_OUI >> 0) & 0xff;
2343 	frm[3] = (BCM_OUI >> 8) & 0xff;
2344 	frm[4] = (BCM_OUI >> 16) & 0xff;
2345 	frm[5] = BCM_OUI_HTCAP;
2346 	return ieee80211_add_htcap_body(frm + 6, ni);
2347 }
2348 
2349 /*
2350  * Construct the MCS bit mask of basic rates
2351  * for inclusion in an HT information element.
2352  */
2353 static void
2354 ieee80211_set_basic_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2355 {
2356 	int i;
2357 
2358 	for (i = 0; i < rs->rs_nrates; i++) {
2359 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2360 		if ((rs->rs_rates[i] & IEEE80211_RATE_BASIC) &&
2361 		    r < IEEE80211_HTRATE_MAXSIZE) {
2362 			/* NB: this assumes a particular implementation */
2363 			setbit(frm, r);
2364 		}
2365 	}
2366 }
2367 
2368 /*
2369  * Update the HTINFO ie for a beacon frame.
2370  */
2371 void
2372 ieee80211_ht_update_beacon(struct ieee80211vap *vap,
2373 	struct ieee80211_beacon_offsets *bo)
2374 {
2375 #define	PROTMODE	(IEEE80211_HTINFO_OPMODE|IEEE80211_HTINFO_NONHT_PRESENT)
2376 	const struct ieee80211_channel *bsschan = vap->iv_bss->ni_chan;
2377 	struct ieee80211com *ic = vap->iv_ic;
2378 	struct ieee80211_ie_htinfo *ht =
2379 	   (struct ieee80211_ie_htinfo *) bo->bo_htinfo;
2380 
2381 	/* XXX only update on channel change */
2382 	ht->hi_ctrlchannel = ieee80211_chan2ieee(ic, bsschan);
2383 	if (vap->iv_flags_ext & IEEE80211_FEXT_RIFS)
2384 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PERM;
2385 	else
2386 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PROH;
2387 	if (IEEE80211_IS_CHAN_HT40U(bsschan))
2388 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2389 	else if (IEEE80211_IS_CHAN_HT40D(bsschan))
2390 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2391 	else
2392 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_NONE;
2393 	if (IEEE80211_IS_CHAN_HT40(bsschan))
2394 		ht->hi_byte1 |= IEEE80211_HTINFO_TXWIDTH_2040;
2395 
2396 	/* protection mode */
2397 	ht->hi_byte2 = (ht->hi_byte2 &~ PROTMODE) | ic->ic_curhtprotmode;
2398 
2399 	/* XXX propagate to vendor ie's */
2400 #undef PROTMODE
2401 }
2402 
2403 /*
2404  * Add body of an HTINFO information element.
2405  *
2406  * NB: We don't use struct ieee80211_ie_htinfo because we can
2407  * be called to fillin both a standard ie and a compat ie that
2408  * has a vendor OUI at the front.
2409  */
2410 static uint8_t *
2411 ieee80211_add_htinfo_body(uint8_t *frm, struct ieee80211_node *ni)
2412 {
2413 	struct ieee80211vap *vap = ni->ni_vap;
2414 	struct ieee80211com *ic = ni->ni_ic;
2415 
2416 	/* pre-zero remainder of ie */
2417 	memset(frm, 0, sizeof(struct ieee80211_ie_htinfo) - 2);
2418 
2419 	/* primary/control channel center */
2420 	*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2421 
2422 	if (vap->iv_flags_ext & IEEE80211_FEXT_RIFS)
2423 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PERM;
2424 	else
2425 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PROH;
2426 	if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
2427 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2428 	else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
2429 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2430 	else
2431 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_NONE;
2432 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2433 		frm[0] |= IEEE80211_HTINFO_TXWIDTH_2040;
2434 
2435 	frm[1] = ic->ic_curhtprotmode;
2436 
2437 	frm += 5;
2438 
2439 	/* basic MCS set */
2440 	ieee80211_set_basic_htrates(frm, &ni->ni_htrates);
2441 	frm += sizeof(struct ieee80211_ie_htinfo) -
2442 		__offsetof(struct ieee80211_ie_htinfo, hi_basicmcsset);
2443 	return frm;
2444 }
2445 
2446 /*
2447  * Add 802.11n HT information information element.
2448  */
2449 uint8_t *
2450 ieee80211_add_htinfo(uint8_t *frm, struct ieee80211_node *ni)
2451 {
2452 	frm[0] = IEEE80211_ELEMID_HTINFO;
2453 	frm[1] = sizeof(struct ieee80211_ie_htinfo) - 2;
2454 	return ieee80211_add_htinfo_body(frm + 2, ni);
2455 }
2456 
2457 /*
2458  * Add Broadcom OUI wrapped standard HTINFO ie; this is
2459  * used for compatibility w/ pre-draft implementations.
2460  */
2461 uint8_t *
2462 ieee80211_add_htinfo_vendor(uint8_t *frm, struct ieee80211_node *ni)
2463 {
2464 	frm[0] = IEEE80211_ELEMID_VENDOR;
2465 	frm[1] = 4 + sizeof(struct ieee80211_ie_htinfo) - 2;
2466 	frm[2] = (BCM_OUI >> 0) & 0xff;
2467 	frm[3] = (BCM_OUI >> 8) & 0xff;
2468 	frm[4] = (BCM_OUI >> 16) & 0xff;
2469 	frm[5] = BCM_OUI_HTINFO;
2470 	return ieee80211_add_htinfo_body(frm + 6, ni);
2471 }
2472