xref: /haiku/src/libs/compat/freebsd_wlan/net80211/ieee80211_ht.c (revision c90684742e7361651849be4116d0e5de3a817194)
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_action.h>
51 #include <net80211/ieee80211_input.h>
52 
53 /* define here, used throughout file */
54 #define	MS(_v, _f)	(((_v) & _f) >> _f##_S)
55 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
56 
57 const struct ieee80211_mcs_rates ieee80211_htrates[16] = {
58 	{  13,  14,  27,  30 },	/* MCS 0 */
59 	{  26,  29,  54,  60 },	/* MCS 1 */
60 	{  39,  43,  81,  90 },	/* MCS 2 */
61 	{  52,  58, 108, 120 },	/* MCS 3 */
62 	{  78,  87, 162, 180 },	/* MCS 4 */
63 	{ 104, 116, 216, 240 },	/* MCS 5 */
64 	{ 117, 130, 243, 270 },	/* MCS 6 */
65 	{ 130, 144, 270, 300 },	/* MCS 7 */
66 	{  26,  29,  54,  60 },	/* MCS 8 */
67 	{  52,  58, 108, 120 },	/* MCS 9 */
68 	{  78,  87, 162, 180 },	/* MCS 10 */
69 	{ 104, 116, 216, 240 },	/* MCS 11 */
70 	{ 156, 173, 324, 360 },	/* MCS 12 */
71 	{ 208, 231, 432, 480 },	/* MCS 13 */
72 	{ 234, 260, 486, 540 },	/* MCS 14 */
73 	{ 260, 289, 540, 600 }	/* MCS 15 */
74 };
75 
76 static const struct ieee80211_htrateset ieee80211_rateset_11n =
77 	{ 16, {
78 	          0,   1,   2,   3,   4,  5,   6,  7,  8,  9,
79 		 10,  11,  12,  13,  14,  15 }
80 	};
81 
82 #ifdef IEEE80211_AMPDU_AGE
83 static	int ieee80211_ampdu_age = -1;	/* threshold for ampdu reorder q (ms) */
84 SYSCTL_PROC(_net_wlan, OID_AUTO, ampdu_age, CTLTYPE_INT | CTLFLAG_RW,
85 	&ieee80211_ampdu_age, 0, ieee80211_sysctl_msecs_ticks, "I",
86 	"AMPDU max reorder age (ms)");
87 #endif
88 
89 static	int ieee80211_recv_bar_ena = 1;
90 SYSCTL_INT(_net_wlan, OID_AUTO, recv_bar, CTLFLAG_RW, &ieee80211_recv_bar_ena,
91 	    0, "BAR frame processing (ena/dis)");
92 
93 static	int ieee80211_addba_timeout = -1;/* timeout for ADDBA response */
94 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_timeout, CTLTYPE_INT | CTLFLAG_RW,
95 	&ieee80211_addba_timeout, 0, ieee80211_sysctl_msecs_ticks, "I",
96 	"ADDBA request timeout (ms)");
97 static	int ieee80211_addba_backoff = -1;/* backoff after max ADDBA requests */
98 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_backoff, CTLTYPE_INT | CTLFLAG_RW,
99 	&ieee80211_addba_backoff, 0, ieee80211_sysctl_msecs_ticks, "I",
100 	"ADDBA request backoff (ms)");
101 static	int ieee80211_addba_maxtries = 3;/* max ADDBA requests before backoff */
102 SYSCTL_INT(_net_wlan, OID_AUTO, addba_maxtries, CTLTYPE_INT | CTLFLAG_RW,
103 	&ieee80211_addba_maxtries, 0, "max ADDBA requests sent before backoff");
104 
105 static	int ieee80211_bar_timeout = -1;	/* timeout waiting for BAR response */
106 static	int ieee80211_bar_maxtries = 50;/* max BAR requests before DELBA */
107 
108 static	ieee80211_recv_action_func ht_recv_action_ba_addba_request;
109 static	ieee80211_recv_action_func ht_recv_action_ba_addba_response;
110 static	ieee80211_recv_action_func ht_recv_action_ba_delba;
111 static	ieee80211_recv_action_func ht_recv_action_ht_mimopwrsave;
112 static	ieee80211_recv_action_func ht_recv_action_ht_txchwidth;
113 
114 static	ieee80211_send_action_func ht_send_action_ba_addba;
115 static	ieee80211_send_action_func ht_send_action_ba_delba;
116 static	ieee80211_send_action_func ht_send_action_ht_txchwidth;
117 
118 void
119 ieee80211_ht_init(void)
120 {
121 	/*
122 	 * Setup HT parameters that depends on the clock frequency.
123 	 */
124 #ifdef IEEE80211_AMPDU_AGE
125 	ieee80211_ampdu_age = msecs_to_ticks(500);
126 #endif
127 	ieee80211_addba_timeout = msecs_to_ticks(250);
128 	ieee80211_addba_backoff = msecs_to_ticks(10*1000);
129 	ieee80211_bar_timeout = msecs_to_ticks(250);
130 	/*
131 	 * Register action frame handlers.
132 	 */
133 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
134 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_recv_action_ba_addba_request);
135 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
136 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_recv_action_ba_addba_response);
137 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
138 	    IEEE80211_ACTION_BA_DELBA, ht_recv_action_ba_delba);
139 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
140 	    IEEE80211_ACTION_HT_MIMOPWRSAVE, ht_recv_action_ht_mimopwrsave);
141 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
142 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_recv_action_ht_txchwidth);
143 
144 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
145 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_send_action_ba_addba);
146 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
147 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_send_action_ba_addba);
148 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
149 	    IEEE80211_ACTION_BA_DELBA, ht_send_action_ba_delba);
150 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_HT,
151 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_send_action_ht_txchwidth);
152 }
153 SYSINIT(wlan_ht, SI_SUB_DRIVERS, SI_ORDER_FIRST, ieee80211_ht_init, NULL);
154 
155 static int ieee80211_ampdu_enable(struct ieee80211_node *ni,
156 	struct ieee80211_tx_ampdu *tap);
157 static int ieee80211_addba_request(struct ieee80211_node *ni,
158 	struct ieee80211_tx_ampdu *tap,
159 	int dialogtoken, int baparamset, int batimeout);
160 static int ieee80211_addba_response(struct ieee80211_node *ni,
161 	struct ieee80211_tx_ampdu *tap,
162 	int code, int baparamset, int batimeout);
163 static void ieee80211_addba_stop(struct ieee80211_node *ni,
164 	struct ieee80211_tx_ampdu *tap);
165 static void ieee80211_bar_response(struct ieee80211_node *ni,
166 	struct ieee80211_tx_ampdu *tap, int status);
167 static void ampdu_tx_stop(struct ieee80211_tx_ampdu *tap);
168 static void bar_stop_timer(struct ieee80211_tx_ampdu *tap);
169 static int ampdu_rx_start(struct ieee80211_node *, struct ieee80211_rx_ampdu *,
170 	int baparamset, int batimeout, int baseqctl);
171 static void ampdu_rx_stop(struct ieee80211_node *, struct ieee80211_rx_ampdu *);
172 
173 void
174 ieee80211_ht_attach(struct ieee80211com *ic)
175 {
176 	/* setup default aggregation policy */
177 	ic->ic_recv_action = ieee80211_recv_action;
178 	ic->ic_send_action = ieee80211_send_action;
179 	ic->ic_ampdu_enable = ieee80211_ampdu_enable;
180 	ic->ic_addba_request = ieee80211_addba_request;
181 	ic->ic_addba_response = ieee80211_addba_response;
182 	ic->ic_addba_stop = ieee80211_addba_stop;
183 	ic->ic_bar_response = ieee80211_bar_response;
184 	ic->ic_ampdu_rx_start = ampdu_rx_start;
185 	ic->ic_ampdu_rx_stop = ampdu_rx_stop;
186 
187 	ic->ic_htprotmode = IEEE80211_PROT_RTSCTS;
188 	ic->ic_curhtprotmode = IEEE80211_HTINFO_OPMODE_PURE;
189 }
190 
191 void
192 ieee80211_ht_detach(struct ieee80211com *ic)
193 {
194 }
195 
196 void
197 ieee80211_ht_vattach(struct ieee80211vap *vap)
198 {
199 
200 	/* driver can override defaults */
201 	vap->iv_ampdu_rxmax = IEEE80211_HTCAP_MAXRXAMPDU_8K;
202 	vap->iv_ampdu_density = IEEE80211_HTCAP_MPDUDENSITY_NA;
203 	vap->iv_ampdu_limit = vap->iv_ampdu_rxmax;
204 	vap->iv_amsdu_limit = vap->iv_htcaps & IEEE80211_HTCAP_MAXAMSDU;
205 	/* tx aggregation traffic thresholds */
206 	vap->iv_ampdu_mintraffic[WME_AC_BK] = 128;
207 	vap->iv_ampdu_mintraffic[WME_AC_BE] = 64;
208 	vap->iv_ampdu_mintraffic[WME_AC_VO] = 32;
209 	vap->iv_ampdu_mintraffic[WME_AC_VI] = 32;
210 
211 	if (vap->iv_htcaps & IEEE80211_HTC_HT) {
212 		/*
213 		 * Device is HT capable; enable all HT-related
214 		 * facilities by default.
215 		 * XXX these choices may be too aggressive.
216 		 */
217 		vap->iv_flags_ht |= IEEE80211_FHT_HT
218 				 |  IEEE80211_FHT_HTCOMPAT
219 				 ;
220 		if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI20)
221 			vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI20;
222 		/* XXX infer from channel list? */
223 		if (vap->iv_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
224 			vap->iv_flags_ht |= IEEE80211_FHT_USEHT40;
225 			if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI40)
226 				vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI40;
227 		}
228 		/* enable RIFS if capable */
229 		if (vap->iv_htcaps & IEEE80211_HTC_RIFS)
230 			vap->iv_flags_ht |= IEEE80211_FHT_RIFS;
231 
232 		/* NB: A-MPDU and A-MSDU rx are mandated, these are tx only */
233 		vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_RX;
234 		if (vap->iv_htcaps & IEEE80211_HTC_AMPDU)
235 			vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_TX;
236 		vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_RX;
237 		if (vap->iv_htcaps & IEEE80211_HTC_AMSDU)
238 			vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_TX;
239 	}
240 	/* NB: disable default legacy WDS, too many issues right now */
241 	if (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)
242 		vap->iv_flags_ht &= ~IEEE80211_FHT_HT;
243 }
244 
245 void
246 ieee80211_ht_vdetach(struct ieee80211vap *vap)
247 {
248 }
249 
250 static void
251 ht_announce(struct ieee80211com *ic, int mode,
252 	const struct ieee80211_htrateset *rs)
253 {
254 	struct ifnet *ifp = ic->ic_ifp;
255 	int i, rate, mword;
256 
257 	if_printf(ifp, "%s MCS: ", ieee80211_phymode_name[mode]);
258 	for (i = 0; i < rs->rs_nrates; i++) {
259 		mword = ieee80211_rate2media(ic,
260 		    rs->rs_rates[i] | IEEE80211_RATE_MCS, mode);
261 		if (IFM_SUBTYPE(mword) != IFM_IEEE80211_MCS)
262 			continue;
263 		rate = ieee80211_htrates[rs->rs_rates[i]].ht40_rate_400ns;
264 		printf("%s%d%sMbps", (i != 0 ? " " : ""),
265 		    rate / 2, ((rate & 0x1) != 0 ? ".5" : ""));
266 	}
267 	printf("\n");
268 }
269 
270 void
271 ieee80211_ht_announce(struct ieee80211com *ic)
272 {
273 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
274 		ht_announce(ic, IEEE80211_MODE_11NA, &ieee80211_rateset_11n);
275 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
276 		ht_announce(ic, IEEE80211_MODE_11NG, &ieee80211_rateset_11n);
277 }
278 
279 const struct ieee80211_htrateset *
280 ieee80211_get_suphtrates(struct ieee80211com *ic,
281 	const struct ieee80211_channel *c)
282 {
283 	return &ieee80211_rateset_11n;
284 }
285 
286 /*
287  * Receive processing.
288  */
289 
290 /*
291  * Decap the encapsulated A-MSDU frames and dispatch all but
292  * the last for delivery.  The last frame is returned for
293  * delivery via the normal path.
294  */
295 struct mbuf *
296 ieee80211_decap_amsdu(struct ieee80211_node *ni, struct mbuf *m)
297 {
298 	struct ieee80211vap *vap = ni->ni_vap;
299 	int framelen;
300 	struct mbuf *n;
301 
302 	/* discard 802.3 header inserted by ieee80211_decap */
303 	m_adj(m, sizeof(struct ether_header));
304 
305 	vap->iv_stats.is_amsdu_decap++;
306 
307 	for (;;) {
308 		/*
309 		 * Decap the first frame, bust it apart from the
310 		 * remainder and deliver.  We leave the last frame
311 		 * delivery to the caller (for consistency with other
312 		 * code paths, could also do it here).
313 		 */
314 		m = ieee80211_decap1(m, &framelen);
315 		if (m == NULL) {
316 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
317 			    ni->ni_macaddr, "a-msdu", "%s", "decap failed");
318 			vap->iv_stats.is_amsdu_tooshort++;
319 			return NULL;
320 		}
321 		if (m->m_pkthdr.len == framelen)
322 			break;
323 		n = m_split(m, framelen, M_NOWAIT);
324 		if (n == NULL) {
325 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
326 			    ni->ni_macaddr, "a-msdu",
327 			    "%s", "unable to split encapsulated frames");
328 			vap->iv_stats.is_amsdu_split++;
329 			m_freem(m);			/* NB: must reclaim */
330 			return NULL;
331 		}
332 		vap->iv_deliver_data(vap, ni, m);
333 
334 		/*
335 		 * Remove frame contents; each intermediate frame
336 		 * is required to be aligned to a 4-byte boundary.
337 		 */
338 		m = n;
339 		m_adj(m, roundup2(framelen, 4) - framelen);	/* padding */
340 	}
341 	return m;				/* last delivered by caller */
342 }
343 
344 /*
345  * Purge all frames in the A-MPDU re-order queue.
346  */
347 static void
348 ampdu_rx_purge(struct ieee80211_rx_ampdu *rap)
349 {
350 	struct mbuf *m;
351 	int i;
352 
353 	for (i = 0; i < rap->rxa_wnd; i++) {
354 		m = rap->rxa_m[i];
355 		if (m != NULL) {
356 			rap->rxa_m[i] = NULL;
357 			rap->rxa_qbytes -= m->m_pkthdr.len;
358 			m_freem(m);
359 			if (--rap->rxa_qframes == 0)
360 				break;
361 		}
362 	}
363 	KASSERT(rap->rxa_qbytes == 0 && rap->rxa_qframes == 0,
364 	    ("lost %u data, %u frames on ampdu rx q",
365 	    rap->rxa_qbytes, rap->rxa_qframes));
366 }
367 
368 /*
369  * Start A-MPDU rx/re-order processing for the specified TID.
370  */
371 static int
372 ampdu_rx_start(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap,
373 	int baparamset, int batimeout, int baseqctl)
374 {
375 	int bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
376 
377 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
378 		/*
379 		 * AMPDU previously setup and not terminated with a DELBA,
380 		 * flush the reorder q's in case anything remains.
381 		 */
382 		ampdu_rx_purge(rap);
383 	}
384 	memset(rap, 0, sizeof(*rap));
385 	rap->rxa_wnd = (bufsiz == 0) ?
386 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
387 	rap->rxa_start = MS(baseqctl, IEEE80211_BASEQ_START);
388 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
389 
390 	return 0;
391 }
392 
393 /*
394  * Stop A-MPDU rx processing for the specified TID.
395  */
396 static void
397 ampdu_rx_stop(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
398 {
399 	ampdu_rx_purge(rap);
400 	rap->rxa_flags &= ~(IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND);
401 }
402 
403 /*
404  * Dispatch a frame from the A-MPDU reorder queue.  The
405  * frame is fed back into ieee80211_input marked with an
406  * M_AMPDU_MPDU flag so it doesn't come back to us (it also
407  * permits ieee80211_input to optimize re-processing).
408  */
409 static __inline void
410 ampdu_dispatch(struct ieee80211_node *ni, struct mbuf *m)
411 {
412 	m->m_flags |= M_AMPDU_MPDU;	/* bypass normal processing */
413 	/* NB: rssi and noise are ignored w/ M_AMPDU_MPDU set */
414 	(void) ieee80211_input(ni, m, 0, 0);
415 }
416 
417 /*
418  * Dispatch as many frames as possible from the re-order queue.
419  * Frames will always be "at the front"; we process all frames
420  * up to the first empty slot in the window.  On completion we
421  * cleanup state if there are still pending frames in the current
422  * BA window.  We assume the frame at slot 0 is already handled
423  * by the caller; we always start at slot 1.
424  */
425 static void
426 ampdu_rx_dispatch(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni)
427 {
428 	struct ieee80211vap *vap = ni->ni_vap;
429 	struct mbuf *m;
430 	int i;
431 
432 	/* flush run of frames */
433 	for (i = 1; i < rap->rxa_wnd; i++) {
434 		m = rap->rxa_m[i];
435 		if (m == NULL)
436 			break;
437 		rap->rxa_m[i] = NULL;
438 		rap->rxa_qbytes -= m->m_pkthdr.len;
439 		rap->rxa_qframes--;
440 
441 		ampdu_dispatch(ni, m);
442 	}
443 	/*
444 	 * If frames remain, copy the mbuf pointers down so
445 	 * they correspond to the offsets in the new window.
446 	 */
447 	if (rap->rxa_qframes != 0) {
448 		int n = rap->rxa_qframes, j;
449 		for (j = i+1; j < rap->rxa_wnd; j++) {
450 			if (rap->rxa_m[j] != NULL) {
451 				rap->rxa_m[j-i] = rap->rxa_m[j];
452 				rap->rxa_m[j] = NULL;
453 				if (--n == 0)
454 					break;
455 			}
456 		}
457 		KASSERT(n == 0, ("lost %d frames", n));
458 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
459 	}
460 	/*
461 	 * Adjust the start of the BA window to
462 	 * reflect the frames just dispatched.
463 	 */
464 	rap->rxa_start = IEEE80211_SEQ_ADD(rap->rxa_start, i);
465 	vap->iv_stats.is_ampdu_rx_oor += i;
466 }
467 
468 #ifdef IEEE80211_AMPDU_AGE
469 /*
470  * Dispatch all frames in the A-MPDU re-order queue.
471  */
472 static void
473 ampdu_rx_flush(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
474 {
475 	struct ieee80211vap *vap = ni->ni_vap;
476 	struct mbuf *m;
477 	int i;
478 
479 	for (i = 0; i < rap->rxa_wnd; i++) {
480 		m = rap->rxa_m[i];
481 		if (m == NULL)
482 			continue;
483 		rap->rxa_m[i] = NULL;
484 		rap->rxa_qbytes -= m->m_pkthdr.len;
485 		rap->rxa_qframes--;
486 		vap->iv_stats.is_ampdu_rx_oor++;
487 
488 		ampdu_dispatch(ni, m);
489 		if (rap->rxa_qframes == 0)
490 			break;
491 	}
492 }
493 #endif /* IEEE80211_AMPDU_AGE */
494 
495 /*
496  * Dispatch all frames in the A-MPDU re-order queue
497  * preceding the specified sequence number.  This logic
498  * handles window moves due to a received MSDU or BAR.
499  */
500 static void
501 ampdu_rx_flush_upto(struct ieee80211_node *ni,
502 	struct ieee80211_rx_ampdu *rap, ieee80211_seq winstart)
503 {
504 	struct ieee80211vap *vap = ni->ni_vap;
505 	struct mbuf *m;
506 	ieee80211_seq seqno;
507 	int i;
508 
509 	/*
510 	 * Flush any complete MSDU's with a sequence number lower
511 	 * than winstart.  Gaps may exist.  Note that we may actually
512 	 * dispatch frames past winstart if a run continues; this is
513 	 * an optimization that avoids having to do a separate pass
514 	 * to dispatch frames after moving the BA window start.
515 	 */
516 	seqno = rap->rxa_start;
517 	for (i = 0; i < rap->rxa_wnd; i++) {
518 		m = rap->rxa_m[i];
519 		if (m != NULL) {
520 			rap->rxa_m[i] = NULL;
521 			rap->rxa_qbytes -= m->m_pkthdr.len;
522 			rap->rxa_qframes--;
523 			vap->iv_stats.is_ampdu_rx_oor++;
524 
525 			ampdu_dispatch(ni, m);
526 		} else {
527 			if (!IEEE80211_SEQ_BA_BEFORE(seqno, winstart))
528 				break;
529 		}
530 		seqno = IEEE80211_SEQ_INC(seqno);
531 	}
532 	/*
533 	 * If frames remain, copy the mbuf pointers down so
534 	 * they correspond to the offsets in the new window.
535 	 */
536 	if (rap->rxa_qframes != 0) {
537 		int n = rap->rxa_qframes, j;
538 
539 		/* NB: this loop assumes i > 0 and/or rxa_m[0] is NULL */
540 		KASSERT(rap->rxa_m[0] == NULL,
541 		    ("%s: BA window slot 0 occupied", __func__));
542 		for (j = i+1; j < rap->rxa_wnd; j++) {
543 			if (rap->rxa_m[j] != NULL) {
544 				rap->rxa_m[j-i] = rap->rxa_m[j];
545 				rap->rxa_m[j] = NULL;
546 				if (--n == 0)
547 					break;
548 			}
549 		}
550 		KASSERT(n == 0, ("%s: lost %d frames, qframes %d off %d "
551 		    "BA win <%d:%d> winstart %d",
552 		    __func__, n, rap->rxa_qframes, i, rap->rxa_start,
553 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
554 		    winstart));
555 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
556 	}
557 	/*
558 	 * Move the start of the BA window; we use the
559 	 * sequence number of the last MSDU that was
560 	 * passed up the stack+1 or winstart if stopped on
561 	 * a gap in the reorder buffer.
562 	 */
563 	rap->rxa_start = seqno;
564 }
565 
566 /*
567  * Process a received QoS data frame for an HT station.  Handle
568  * A-MPDU reordering: if this frame is received out of order
569  * and falls within the BA window hold onto it.  Otherwise if
570  * this frame completes a run, flush any pending frames.  We
571  * return 1 if the frame is consumed.  A 0 is returned if
572  * the frame should be processed normally by the caller.
573  */
574 int
575 ieee80211_ampdu_reorder(struct ieee80211_node *ni, struct mbuf *m)
576 {
577 #define	IEEE80211_FC0_QOSDATA \
578 	(IEEE80211_FC0_TYPE_DATA|IEEE80211_FC0_SUBTYPE_QOS|IEEE80211_FC0_VERSION_0)
579 #define	PROCESS		0	/* caller should process frame */
580 #define	CONSUMED	1	/* frame consumed, caller does nothing */
581 	struct ieee80211vap *vap = ni->ni_vap;
582 	struct ieee80211_qosframe *wh;
583 	struct ieee80211_rx_ampdu *rap;
584 	ieee80211_seq rxseq;
585 	uint8_t tid;
586 	int off;
587 
588 	KASSERT((m->m_flags & (M_AMPDU | M_AMPDU_MPDU)) == M_AMPDU,
589 	    ("!a-mpdu or already re-ordered, flags 0x%x", m->m_flags));
590 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
591 
592 	/* NB: m_len known to be sufficient */
593 	wh = mtod(m, struct ieee80211_qosframe *);
594 	if (wh->i_fc[0] != IEEE80211_FC0_QOSDATA) {
595 		/*
596 		 * Not QoS data, shouldn't get here but just
597 		 * return it to the caller for processing.
598 		 */
599 		return PROCESS;
600 	}
601 	if (IEEE80211_IS_DSTODS(wh))
602 		tid = ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0];
603 	else
604 		tid = wh->i_qos[0];
605 	tid &= IEEE80211_QOS_TID;
606 	rap = &ni->ni_rx_ampdu[tid];
607 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
608 		/*
609 		 * No ADDBA request yet, don't touch.
610 		 */
611 		return PROCESS;
612 	}
613 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
614 	if ((rxseq & IEEE80211_SEQ_FRAG_MASK) != 0) {
615 		/*
616 		 * Fragments are not allowed; toss.
617 		 */
618 		IEEE80211_DISCARD_MAC(vap,
619 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
620 		    "A-MPDU", "fragment, rxseq 0x%x tid %u%s", rxseq, tid,
621 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
622 		vap->iv_stats.is_ampdu_rx_drop++;
623 		IEEE80211_NODE_STAT(ni, rx_drop);
624 		m_freem(m);
625 		return CONSUMED;
626 	}
627 	rxseq >>= IEEE80211_SEQ_SEQ_SHIFT;
628 	rap->rxa_nframes++;
629 again:
630 	if (rxseq == rap->rxa_start) {
631 		/*
632 		 * First frame in window.
633 		 */
634 		if (rap->rxa_qframes != 0) {
635 			/*
636 			 * Dispatch as many packets as we can.
637 			 */
638 			KASSERT(rap->rxa_m[0] == NULL, ("unexpected dup"));
639 			ampdu_dispatch(ni, m);
640 			ampdu_rx_dispatch(rap, ni);
641 			return CONSUMED;
642 		} else {
643 			/*
644 			 * In order; advance window and notify
645 			 * caller to dispatch directly.
646 			 */
647 			rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
648 			return PROCESS;
649 		}
650 	}
651 	/*
652 	 * Frame is out of order; store if in the BA window.
653 	 */
654 	/* calculate offset in BA window */
655 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
656 	if (off < rap->rxa_wnd) {
657 		/*
658 		 * Common case (hopefully): in the BA window.
659 		 * Sec 9.10.7.6 a) (D2.04 p.118 line 47)
660 		 */
661 #ifdef IEEE80211_AMPDU_AGE
662 		/*
663 		 * Check for frames sitting too long in the reorder queue.
664 		 * This should only ever happen if frames are not delivered
665 		 * without the sender otherwise notifying us (e.g. with a
666 		 * BAR to move the window).  Typically this happens because
667 		 * of vendor bugs that cause the sequence number to jump.
668 		 * When this happens we get a gap in the reorder queue that
669 		 * leaves frame sitting on the queue until they get pushed
670 		 * out due to window moves.  When the vendor does not send
671 		 * BAR this move only happens due to explicit packet sends
672 		 *
673 		 * NB: we only track the time of the oldest frame in the
674 		 * reorder q; this means that if we flush we might push
675 		 * frames that still "new"; if this happens then subsequent
676 		 * frames will result in BA window moves which cost something
677 		 * but is still better than a big throughput dip.
678 		 */
679 		if (rap->rxa_qframes != 0) {
680 			/* XXX honor batimeout? */
681 			if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
682 				/*
683 				 * Too long since we received the first
684 				 * frame; flush the reorder buffer.
685 				 */
686 				if (rap->rxa_qframes != 0) {
687 					vap->iv_stats.is_ampdu_rx_age +=
688 					    rap->rxa_qframes;
689 					ampdu_rx_flush(ni, rap);
690 				}
691 				rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
692 				return PROCESS;
693 			}
694 		} else {
695 			/*
696 			 * First frame, start aging timer.
697 			 */
698 			rap->rxa_age = ticks;
699 		}
700 #endif /* IEEE80211_AMPDU_AGE */
701 		/* save packet */
702 		if (rap->rxa_m[off] == NULL) {
703 			rap->rxa_m[off] = m;
704 			rap->rxa_qframes++;
705 			rap->rxa_qbytes += m->m_pkthdr.len;
706 			vap->iv_stats.is_ampdu_rx_reorder++;
707 		} else {
708 			IEEE80211_DISCARD_MAC(vap,
709 			    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
710 			    ni->ni_macaddr, "a-mpdu duplicate",
711 			    "seqno %u tid %u BA win <%u:%u>",
712 			    rxseq, tid, rap->rxa_start,
713 			    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1));
714 			vap->iv_stats.is_rx_dup++;
715 			IEEE80211_NODE_STAT(ni, rx_dup);
716 			m_freem(m);
717 		}
718 		return CONSUMED;
719 	}
720 	if (off < IEEE80211_SEQ_BA_RANGE) {
721 		/*
722 		 * Outside the BA window, but within range;
723 		 * flush the reorder q and move the window.
724 		 * Sec 9.10.7.6 b) (D2.04 p.118 line 60)
725 		 */
726 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
727 		    "move BA win <%u:%u> (%u frames) rxseq %u tid %u",
728 		    rap->rxa_start,
729 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
730 		    rap->rxa_qframes, rxseq, tid);
731 		vap->iv_stats.is_ampdu_rx_move++;
732 
733 		/*
734 		 * The spec says to flush frames up to but not including:
735 		 * 	WinStart_B = rxseq - rap->rxa_wnd + 1
736 		 * Then insert the frame or notify the caller to process
737 		 * it immediately.  We can safely do this by just starting
738 		 * over again because we know the frame will now be within
739 		 * the BA window.
740 		 */
741 		/* NB: rxa_wnd known to be >0 */
742 		ampdu_rx_flush_upto(ni, rap,
743 		    IEEE80211_SEQ_SUB(rxseq, rap->rxa_wnd-1));
744 		goto again;
745 	} else {
746 		/*
747 		 * Outside the BA window and out of range; toss.
748 		 * Sec 9.10.7.6 c) (D2.04 p.119 line 16)
749 		 */
750 		IEEE80211_DISCARD_MAC(vap,
751 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
752 		    "MPDU", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
753 		    rap->rxa_start,
754 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
755 		    rap->rxa_qframes, rxseq, tid,
756 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
757 		vap->iv_stats.is_ampdu_rx_drop++;
758 		IEEE80211_NODE_STAT(ni, rx_drop);
759 		m_freem(m);
760 		return CONSUMED;
761 	}
762 #undef CONSUMED
763 #undef PROCESS
764 #undef IEEE80211_FC0_QOSDATA
765 }
766 
767 /*
768  * Process a BAR ctl frame.  Dispatch all frames up to
769  * the sequence number of the frame.  If this frame is
770  * out of range it's discarded.
771  */
772 void
773 ieee80211_recv_bar(struct ieee80211_node *ni, struct mbuf *m0)
774 {
775 	struct ieee80211vap *vap = ni->ni_vap;
776 	struct ieee80211_frame_bar *wh;
777 	struct ieee80211_rx_ampdu *rap;
778 	ieee80211_seq rxseq;
779 	int tid, off;
780 
781 	if (!ieee80211_recv_bar_ena) {
782 #if 0
783 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_11N,
784 		    ni->ni_macaddr, "BAR", "%s", "processing disabled");
785 #endif
786 		vap->iv_stats.is_ampdu_bar_bad++;
787 		return;
788 	}
789 	wh = mtod(m0, struct ieee80211_frame_bar *);
790 	/* XXX check basic BAR */
791 	tid = MS(le16toh(wh->i_ctl), IEEE80211_BAR_TID);
792 	rap = &ni->ni_rx_ampdu[tid];
793 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
794 		/*
795 		 * No ADDBA request yet, don't touch.
796 		 */
797 		IEEE80211_DISCARD_MAC(vap,
798 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
799 		    ni->ni_macaddr, "BAR", "no BA stream, tid %u", tid);
800 		vap->iv_stats.is_ampdu_bar_bad++;
801 		return;
802 	}
803 	vap->iv_stats.is_ampdu_bar_rx++;
804 	rxseq = le16toh(wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
805 	if (rxseq == rap->rxa_start)
806 		return;
807 	/* calculate offset in BA window */
808 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
809 	if (off < IEEE80211_SEQ_BA_RANGE) {
810 		/*
811 		 * Flush the reorder q up to rxseq and move the window.
812 		 * Sec 9.10.7.6 a) (D2.04 p.119 line 22)
813 		 */
814 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
815 		    "BAR moves BA win <%u:%u> (%u frames) rxseq %u tid %u",
816 		    rap->rxa_start,
817 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
818 		    rap->rxa_qframes, rxseq, tid);
819 		vap->iv_stats.is_ampdu_bar_move++;
820 
821 		ampdu_rx_flush_upto(ni, rap, rxseq);
822 		if (off >= rap->rxa_wnd) {
823 			/*
824 			 * BAR specifies a window start to the right of BA
825 			 * window; we must move it explicitly since
826 			 * ampdu_rx_flush_upto will not.
827 			 */
828 			rap->rxa_start = rxseq;
829 		}
830 	} else {
831 		/*
832 		 * Out of range; toss.
833 		 * Sec 9.10.7.6 b) (D2.04 p.119 line 41)
834 		 */
835 		IEEE80211_DISCARD_MAC(vap,
836 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
837 		    "BAR", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
838 		    rap->rxa_start,
839 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
840 		    rap->rxa_qframes, rxseq, tid,
841 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
842 		vap->iv_stats.is_ampdu_bar_oow++;
843 		IEEE80211_NODE_STAT(ni, rx_drop);
844 	}
845 }
846 
847 /*
848  * Setup HT-specific state in a node.  Called only
849  * when HT use is negotiated so we don't do extra
850  * work for temporary and/or legacy sta's.
851  */
852 void
853 ieee80211_ht_node_init(struct ieee80211_node *ni)
854 {
855 	struct ieee80211_tx_ampdu *tap;
856 	int ac;
857 
858 	if (ni->ni_flags & IEEE80211_NODE_HT) {
859 		/*
860 		 * Clean AMPDU state on re-associate.  This handles the case
861 		 * where a station leaves w/o notifying us and then returns
862 		 * before node is reaped for inactivity.
863 		 */
864 		ieee80211_ht_node_cleanup(ni);
865 	}
866 	for (ac = 0; ac < WME_NUM_AC; ac++) {
867 		tap = &ni->ni_tx_ampdu[ac];
868 		tap->txa_ac = ac;
869 		tap->txa_ni = ni;
870 		/* NB: further initialization deferred */
871 	}
872 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
873 }
874 
875 /*
876  * Cleanup HT-specific state in a node.  Called only
877  * when HT use has been marked.
878  */
879 void
880 ieee80211_ht_node_cleanup(struct ieee80211_node *ni)
881 {
882 	struct ieee80211com *ic = ni->ni_ic;
883 	int i;
884 
885 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT node"));
886 
887 	/* XXX optimize this */
888 	for (i = 0; i < WME_NUM_AC; i++) {
889 		struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[i];
890 		if (tap->txa_flags & IEEE80211_AGGR_SETUP)
891 			ampdu_tx_stop(tap);
892 	}
893 	for (i = 0; i < WME_NUM_TID; i++)
894 		ic->ic_ampdu_rx_stop(ni, &ni->ni_rx_ampdu[i]);
895 
896 	ni->ni_htcap = 0;
897 	ni->ni_flags &= ~IEEE80211_NODE_HT_ALL;
898 }
899 
900 /*
901  * Age out HT resources for a station.
902  */
903 void
904 ieee80211_ht_node_age(struct ieee80211_node *ni)
905 {
906 #ifdef IEEE80211_AMPDU_AGE
907 	struct ieee80211vap *vap = ni->ni_vap;
908 	uint8_t tid;
909 #endif
910 
911 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
912 
913 #ifdef IEEE80211_AMPDU_AGE
914 	for (tid = 0; tid < WME_NUM_TID; tid++) {
915 		struct ieee80211_rx_ampdu *rap;
916 
917 		rap = &ni->ni_rx_ampdu[tid];
918 		if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0)
919 			continue;
920 		if (rap->rxa_qframes == 0)
921 			continue;
922 		/*
923 		 * Check for frames sitting too long in the reorder queue.
924 		 * See above for more details on what's happening here.
925 		 */
926 		/* XXX honor batimeout? */
927 		if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
928 			/*
929 			 * Too long since we received the first
930 			 * frame; flush the reorder buffer.
931 			 */
932 			vap->iv_stats.is_ampdu_rx_age += rap->rxa_qframes;
933 			ampdu_rx_flush(ni, rap);
934 		}
935 	}
936 #endif /* IEEE80211_AMPDU_AGE */
937 }
938 
939 static struct ieee80211_channel *
940 findhtchan(struct ieee80211com *ic, struct ieee80211_channel *c, int htflags)
941 {
942 	return ieee80211_find_channel(ic, c->ic_freq,
943 	    (c->ic_flags &~ IEEE80211_CHAN_HT) | htflags);
944 }
945 
946 /*
947  * Adjust a channel to be HT/non-HT according to the vap's configuration.
948  */
949 struct ieee80211_channel *
950 ieee80211_ht_adjust_channel(struct ieee80211com *ic,
951 	struct ieee80211_channel *chan, int flags)
952 {
953 	struct ieee80211_channel *c;
954 
955 	if (flags & IEEE80211_FHT_HT) {
956 		/* promote to HT if possible */
957 		if (flags & IEEE80211_FHT_USEHT40) {
958 			if (!IEEE80211_IS_CHAN_HT40(chan)) {
959 				/* NB: arbitrarily pick ht40+ over ht40- */
960 				c = findhtchan(ic, chan, IEEE80211_CHAN_HT40U);
961 				if (c == NULL)
962 					c = findhtchan(ic, chan,
963 						IEEE80211_CHAN_HT40D);
964 				if (c == NULL)
965 					c = findhtchan(ic, chan,
966 						IEEE80211_CHAN_HT20);
967 				if (c != NULL)
968 					chan = c;
969 			}
970 		} else if (!IEEE80211_IS_CHAN_HT20(chan)) {
971 			c = findhtchan(ic, chan, IEEE80211_CHAN_HT20);
972 			if (c != NULL)
973 				chan = c;
974 		}
975 	} else if (IEEE80211_IS_CHAN_HT(chan)) {
976 		/* demote to legacy, HT use is disabled */
977 		c = ieee80211_find_channel(ic, chan->ic_freq,
978 		    chan->ic_flags &~ IEEE80211_CHAN_HT);
979 		if (c != NULL)
980 			chan = c;
981 	}
982 	return chan;
983 }
984 
985 /*
986  * Setup HT-specific state for a legacy WDS peer.
987  */
988 void
989 ieee80211_ht_wds_init(struct ieee80211_node *ni)
990 {
991 	struct ieee80211vap *vap = ni->ni_vap;
992 	struct ieee80211_tx_ampdu *tap;
993 	int ac;
994 
995 	KASSERT(vap->iv_flags_ht & IEEE80211_FHT_HT, ("no HT requested"));
996 
997 	/* XXX check scan cache in case peer has an ap and we have info */
998 	/*
999 	 * If setup with a legacy channel; locate an HT channel.
1000 	 * Otherwise if the inherited channel (from a companion
1001 	 * AP) is suitable use it so we use the same location
1002 	 * for the extension channel).
1003 	 */
1004 	ni->ni_chan = ieee80211_ht_adjust_channel(ni->ni_ic,
1005 	    ni->ni_chan, ieee80211_htchanflags(ni->ni_chan));
1006 
1007 	ni->ni_htcap = 0;
1008 	if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20)
1009 		ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI20;
1010 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan)) {
1011 		ni->ni_htcap |= IEEE80211_HTCAP_CHWIDTH40;
1012 		ni->ni_chw = 40;
1013 		if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
1014 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_ABOVE;
1015 		else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
1016 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_BELOW;
1017 		if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40)
1018 			ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI40;
1019 	} else {
1020 		ni->ni_chw = 20;
1021 		ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_NONE;
1022 	}
1023 	ni->ni_htctlchan = ni->ni_chan->ic_ieee;
1024 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
1025 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1026 	/* XXX does it make sense to enable SMPS? */
1027 
1028 	ni->ni_htopmode = 0;		/* XXX need protection state */
1029 	ni->ni_htstbc = 0;		/* XXX need info */
1030 
1031 	for (ac = 0; ac < WME_NUM_AC; ac++) {
1032 		tap = &ni->ni_tx_ampdu[ac];
1033 		tap->txa_ac = ac;
1034 	}
1035 	/* NB: AMPDU tx/rx governed by IEEE80211_FHT_AMPDU_{TX,RX} */
1036 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1037 }
1038 
1039 /*
1040  * Notify hostap vaps of a change in the HTINFO ie.
1041  */
1042 static void
1043 htinfo_notify(struct ieee80211com *ic)
1044 {
1045 	struct ieee80211vap *vap;
1046 	int first = 1;
1047 
1048 	IEEE80211_LOCK_ASSERT(ic);
1049 
1050 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
1051 		if (vap->iv_opmode != IEEE80211_M_HOSTAP)
1052 			continue;
1053 		if (vap->iv_state != IEEE80211_S_RUN ||
1054 		    !IEEE80211_IS_CHAN_HT(vap->iv_bss->ni_chan))
1055 			continue;
1056 		if (first) {
1057 			IEEE80211_NOTE(vap,
1058 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1059 			    vap->iv_bss,
1060 			    "HT bss occupancy change: %d sta, %d ht, "
1061 			    "%d ht40%s, HT protmode now 0x%x"
1062 			    , ic->ic_sta_assoc
1063 			    , ic->ic_ht_sta_assoc
1064 			    , ic->ic_ht40_sta_assoc
1065 			    , (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) ?
1066 				 ", non-HT sta present" : ""
1067 			    , ic->ic_curhtprotmode);
1068 			first = 0;
1069 		}
1070 		ieee80211_beacon_notify(vap, IEEE80211_BEACON_HTINFO);
1071 	}
1072 }
1073 
1074 /*
1075  * Calculate HT protection mode from current
1076  * state and handle updates.
1077  */
1078 static void
1079 htinfo_update(struct ieee80211com *ic)
1080 {
1081 	uint8_t protmode;
1082 
1083 	if (ic->ic_sta_assoc != ic->ic_ht_sta_assoc) {
1084 		protmode = IEEE80211_HTINFO_OPMODE_MIXED
1085 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1086 	} else if (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) {
1087 		protmode = IEEE80211_HTINFO_OPMODE_PROTOPT
1088 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1089 	} else if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
1090 	    IEEE80211_IS_CHAN_HT40(ic->ic_bsschan) &&
1091 	    ic->ic_sta_assoc != ic->ic_ht40_sta_assoc) {
1092 		protmode = IEEE80211_HTINFO_OPMODE_HT20PR;
1093 	} else {
1094 		protmode = IEEE80211_HTINFO_OPMODE_PURE;
1095 	}
1096 	if (protmode != ic->ic_curhtprotmode) {
1097 		ic->ic_curhtprotmode = protmode;
1098 		htinfo_notify(ic);
1099 	}
1100 }
1101 
1102 /*
1103  * Handle an HT station joining a BSS.
1104  */
1105 void
1106 ieee80211_ht_node_join(struct ieee80211_node *ni)
1107 {
1108 	struct ieee80211com *ic = ni->ni_ic;
1109 
1110 	IEEE80211_LOCK_ASSERT(ic);
1111 
1112 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1113 		ic->ic_ht_sta_assoc++;
1114 		if (ni->ni_chw == 40)
1115 			ic->ic_ht40_sta_assoc++;
1116 	}
1117 	htinfo_update(ic);
1118 }
1119 
1120 /*
1121  * Handle an HT station leaving a BSS.
1122  */
1123 void
1124 ieee80211_ht_node_leave(struct ieee80211_node *ni)
1125 {
1126 	struct ieee80211com *ic = ni->ni_ic;
1127 
1128 	IEEE80211_LOCK_ASSERT(ic);
1129 
1130 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1131 		ic->ic_ht_sta_assoc--;
1132 		if (ni->ni_chw == 40)
1133 			ic->ic_ht40_sta_assoc--;
1134 	}
1135 	htinfo_update(ic);
1136 }
1137 
1138 /*
1139  * Public version of htinfo_update; used for processing
1140  * beacon frames from overlapping bss.
1141  *
1142  * Caller can specify either IEEE80211_HTINFO_OPMODE_MIXED
1143  * (on receipt of a beacon that advertises MIXED) or
1144  * IEEE80211_HTINFO_OPMODE_PROTOPT (on receipt of a beacon
1145  * from an overlapping legacy bss).  We treat MIXED with
1146  * a higher precedence than PROTOPT (i.e. we will not change
1147  * change PROTOPT -> MIXED; only MIXED -> PROTOPT).  This
1148  * corresponds to how we handle things in htinfo_update.
1149  */
1150 void
1151 ieee80211_htprot_update(struct ieee80211com *ic, int protmode)
1152 {
1153 #define	OPMODE(x)	SM(x, IEEE80211_HTINFO_OPMODE)
1154 	IEEE80211_LOCK(ic);
1155 
1156 	/* track non-HT station presence */
1157 	KASSERT(protmode & IEEE80211_HTINFO_NONHT_PRESENT,
1158 	    ("protmode 0x%x", protmode));
1159 	ic->ic_flags_ht |= IEEE80211_FHT_NONHT_PR;
1160 	ic->ic_lastnonht = ticks;
1161 
1162 	if (protmode != ic->ic_curhtprotmode &&
1163 	    (OPMODE(ic->ic_curhtprotmode) != IEEE80211_HTINFO_OPMODE_MIXED ||
1164 	     OPMODE(protmode) == IEEE80211_HTINFO_OPMODE_PROTOPT)) {
1165 		/* push beacon update */
1166 		ic->ic_curhtprotmode = protmode;
1167 		htinfo_notify(ic);
1168 	}
1169 	IEEE80211_UNLOCK(ic);
1170 #undef OPMODE
1171 }
1172 
1173 /*
1174  * Time out presence of an overlapping bss with non-HT
1175  * stations.  When operating in hostap mode we listen for
1176  * beacons from other stations and if we identify a non-HT
1177  * station is present we update the opmode field of the
1178  * HTINFO ie.  To identify when all non-HT stations are
1179  * gone we time out this condition.
1180  */
1181 void
1182 ieee80211_ht_timeout(struct ieee80211com *ic)
1183 {
1184 	IEEE80211_LOCK_ASSERT(ic);
1185 
1186 	if ((ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) &&
1187 	    time_after(ticks, ic->ic_lastnonht + IEEE80211_NONHT_PRESENT_AGE)) {
1188 #if 0
1189 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1190 		    "%s", "time out non-HT STA present on channel");
1191 #endif
1192 		ic->ic_flags_ht &= ~IEEE80211_FHT_NONHT_PR;
1193 		htinfo_update(ic);
1194 	}
1195 }
1196 
1197 /* unalligned little endian access */
1198 #define LE_READ_2(p)					\
1199 	((uint16_t)					\
1200 	 ((((const uint8_t *)(p))[0]      ) |		\
1201 	  (((const uint8_t *)(p))[1] <<  8)))
1202 
1203 /*
1204  * Process an 802.11n HT capabilities ie.
1205  */
1206 void
1207 ieee80211_parse_htcap(struct ieee80211_node *ni, const uint8_t *ie)
1208 {
1209 	if (ie[0] == IEEE80211_ELEMID_VENDOR) {
1210 		/*
1211 		 * Station used Vendor OUI ie to associate;
1212 		 * mark the node so when we respond we'll use
1213 		 * the Vendor OUI's and not the standard ie's.
1214 		 */
1215 		ni->ni_flags |= IEEE80211_NODE_HTCOMPAT;
1216 		ie += 4;
1217 	} else
1218 		ni->ni_flags &= ~IEEE80211_NODE_HTCOMPAT;
1219 
1220 	ni->ni_htcap = LE_READ_2(ie +
1221 		__offsetof(struct ieee80211_ie_htcap, hc_cap));
1222 	ni->ni_htparam = ie[__offsetof(struct ieee80211_ie_htcap, hc_param)];
1223 }
1224 
1225 static void
1226 htinfo_parse(struct ieee80211_node *ni,
1227 	const struct ieee80211_ie_htinfo *htinfo)
1228 {
1229 	uint16_t w;
1230 
1231 	ni->ni_htctlchan = htinfo->hi_ctrlchannel;
1232 	ni->ni_ht2ndchan = SM(htinfo->hi_byte1, IEEE80211_HTINFO_2NDCHAN);
1233 	w = LE_READ_2(&htinfo->hi_byte2);
1234 	ni->ni_htopmode = SM(w, IEEE80211_HTINFO_OPMODE);
1235 	w = LE_READ_2(&htinfo->hi_byte45);
1236 	ni->ni_htstbc = SM(w, IEEE80211_HTINFO_BASIC_STBCMCS);
1237 }
1238 
1239 /*
1240  * Parse an 802.11n HT info ie and save useful information
1241  * to the node state.  Note this does not effect any state
1242  * changes such as for channel width change.
1243  */
1244 void
1245 ieee80211_parse_htinfo(struct ieee80211_node *ni, const uint8_t *ie)
1246 {
1247 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1248 		ie += 4;
1249 	htinfo_parse(ni, (const struct ieee80211_ie_htinfo *) ie);
1250 }
1251 
1252 /*
1253  * Handle 11n channel switch.  Use the received HT ie's to
1254  * identify the right channel to use.  If we cannot locate it
1255  * in the channel table then fallback to legacy operation.
1256  * Note that we use this information to identify the node's
1257  * channel only; the caller is responsible for insuring any
1258  * required channel change is done (e.g. in sta mode when
1259  * parsing the contents of a beacon frame).
1260  */
1261 static void
1262 htinfo_update_chw(struct ieee80211_node *ni, int htflags)
1263 {
1264 	struct ieee80211com *ic = ni->ni_ic;
1265 	struct ieee80211_channel *c;
1266 	int chanflags;
1267 
1268 	chanflags = (ni->ni_chan->ic_flags &~ IEEE80211_CHAN_HT) | htflags;
1269 	if (chanflags != ni->ni_chan->ic_flags) {
1270 		/* XXX not right for ht40- */
1271 		c = ieee80211_find_channel(ic, ni->ni_chan->ic_freq, chanflags);
1272 		if (c == NULL && (htflags & IEEE80211_CHAN_HT40)) {
1273 			/*
1274 			 * No HT40 channel entry in our table; fall back
1275 			 * to HT20 operation.  This should not happen.
1276 			 */
1277 			c = findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT20);
1278 #if 0
1279 			IEEE80211_NOTE(ni->ni_vap,
1280 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1281 			    "no HT40 channel (freq %u), falling back to HT20",
1282 			    ni->ni_chan->ic_freq);
1283 #endif
1284 			/* XXX stat */
1285 		}
1286 		if (c != NULL && c != ni->ni_chan) {
1287 			IEEE80211_NOTE(ni->ni_vap,
1288 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1289 			    "switch station to HT%d channel %u/0x%x",
1290 			    IEEE80211_IS_CHAN_HT40(c) ? 40 : 20,
1291 			    c->ic_freq, c->ic_flags);
1292 			ni->ni_chan = c;
1293 		}
1294 		/* NB: caller responsible for forcing any channel change */
1295 	}
1296 	/* update node's tx channel width */
1297 	ni->ni_chw = IEEE80211_IS_CHAN_HT40(ni->ni_chan)? 40 : 20;
1298 }
1299 
1300 /*
1301  * Update 11n MIMO PS state according to received htcap.
1302  */
1303 static __inline int
1304 htcap_update_mimo_ps(struct ieee80211_node *ni)
1305 {
1306 	uint16_t oflags = ni->ni_flags;
1307 
1308 	switch (ni->ni_htcap & IEEE80211_HTCAP_SMPS) {
1309 	case IEEE80211_HTCAP_SMPS_DYNAMIC:
1310 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1311 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1312 		break;
1313 	case IEEE80211_HTCAP_SMPS_ENA:
1314 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1315 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1316 		break;
1317 	case IEEE80211_HTCAP_SMPS_OFF:
1318 	default:		/* disable on rx of reserved value */
1319 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1320 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1321 		break;
1322 	}
1323 	return (oflags ^ ni->ni_flags);
1324 }
1325 
1326 /*
1327  * Update short GI state according to received htcap
1328  * and local settings.
1329  */
1330 static __inline void
1331 htcap_update_shortgi(struct ieee80211_node *ni)
1332 {
1333 	struct ieee80211vap *vap = ni->ni_vap;
1334 
1335 	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
1336 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
1337 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20))
1338 		ni->ni_flags |= IEEE80211_NODE_SGI20;
1339 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
1340 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40))
1341 		ni->ni_flags |= IEEE80211_NODE_SGI40;
1342 }
1343 
1344 /*
1345  * Parse and update HT-related state extracted from
1346  * the HT cap and info ie's.
1347  */
1348 void
1349 ieee80211_ht_updateparams(struct ieee80211_node *ni,
1350 	const uint8_t *htcapie, const uint8_t *htinfoie)
1351 {
1352 	struct ieee80211vap *vap = ni->ni_vap;
1353 	const struct ieee80211_ie_htinfo *htinfo;
1354 	int htflags;
1355 
1356 	ieee80211_parse_htcap(ni, htcapie);
1357 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1358 		htcap_update_mimo_ps(ni);
1359 	htcap_update_shortgi(ni);
1360 
1361 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
1362 		htinfoie += 4;
1363 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1364 	htinfo_parse(ni, htinfo);
1365 
1366 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1367 	    IEEE80211_CHAN_HT20 : 0;
1368 	/* NB: honor operating mode constraint */
1369 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_TXWIDTH_2040) &&
1370 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1371 		if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_ABOVE)
1372 			htflags = IEEE80211_CHAN_HT40U;
1373 		else if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_BELOW)
1374 			htflags = IEEE80211_CHAN_HT40D;
1375 	}
1376 	htinfo_update_chw(ni, htflags);
1377 
1378 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_RIFSMODE_PERM) &&
1379 	    (vap->iv_flags_ht & IEEE80211_FHT_RIFS))
1380 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1381 	else
1382 		ni->ni_flags &= ~IEEE80211_NODE_RIFS;
1383 }
1384 
1385 /*
1386  * Parse and update HT-related state extracted from the HT cap ie
1387  * for a station joining an HT BSS.
1388  */
1389 void
1390 ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
1391 {
1392 	struct ieee80211vap *vap = ni->ni_vap;
1393 	int htflags;
1394 
1395 	ieee80211_parse_htcap(ni, htcapie);
1396 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1397 		htcap_update_mimo_ps(ni);
1398 	htcap_update_shortgi(ni);
1399 
1400 	/* NB: honor operating mode constraint */
1401 	/* XXX 40 MHZ intolerant */
1402 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1403 	    IEEE80211_CHAN_HT20 : 0;
1404 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) &&
1405 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1406 		if (IEEE80211_IS_CHAN_HT40U(vap->iv_bss->ni_chan))
1407 			htflags = IEEE80211_CHAN_HT40U;
1408 		else if (IEEE80211_IS_CHAN_HT40D(vap->iv_bss->ni_chan))
1409 			htflags = IEEE80211_CHAN_HT40D;
1410 	}
1411 	htinfo_update_chw(ni, htflags);
1412 }
1413 
1414 /*
1415  * Install received HT rate set by parsing the HT cap ie.
1416  */
1417 int
1418 ieee80211_setup_htrates(struct ieee80211_node *ni, const uint8_t *ie, int flags)
1419 {
1420 	struct ieee80211vap *vap = ni->ni_vap;
1421 	const struct ieee80211_ie_htcap *htcap;
1422 	struct ieee80211_htrateset *rs;
1423 	int i;
1424 
1425 	rs = &ni->ni_htrates;
1426 	memset(rs, 0, sizeof(*rs));
1427 	if (ie != NULL) {
1428 		if (ie[0] == IEEE80211_ELEMID_VENDOR)
1429 			ie += 4;
1430 		htcap = (const struct ieee80211_ie_htcap *) ie;
1431 		for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1432 			if (isclr(htcap->hc_mcsset, i))
1433 				continue;
1434 			if (rs->rs_nrates == IEEE80211_HTRATE_MAXSIZE) {
1435 				IEEE80211_NOTE(vap,
1436 				    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1437 				    "WARNING, HT rate set too large; only "
1438 				    "using %u rates", IEEE80211_HTRATE_MAXSIZE);
1439 				vap->iv_stats.is_rx_rstoobig++;
1440 				break;
1441 			}
1442 			rs->rs_rates[rs->rs_nrates++] = i;
1443 		}
1444 	}
1445 	return ieee80211_fix_rate(ni, (struct ieee80211_rateset *) rs, flags);
1446 }
1447 
1448 /*
1449  * Mark rates in a node's HT rate set as basic according
1450  * to the information in the supplied HT info ie.
1451  */
1452 void
1453 ieee80211_setup_basic_htrates(struct ieee80211_node *ni, const uint8_t *ie)
1454 {
1455 	const struct ieee80211_ie_htinfo *htinfo;
1456 	struct ieee80211_htrateset *rs;
1457 	int i, j;
1458 
1459 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1460 		ie += 4;
1461 	htinfo = (const struct ieee80211_ie_htinfo *) ie;
1462 	rs = &ni->ni_htrates;
1463 	if (rs->rs_nrates == 0) {
1464 		IEEE80211_NOTE(ni->ni_vap,
1465 		    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1466 		    "%s", "WARNING, empty HT rate set");
1467 		return;
1468 	}
1469 	for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1470 		if (isclr(htinfo->hi_basicmcsset, i))
1471 			continue;
1472 		for (j = 0; j < rs->rs_nrates; j++)
1473 			if ((rs->rs_rates[j] & IEEE80211_RATE_VAL) == i)
1474 				rs->rs_rates[j] |= IEEE80211_RATE_BASIC;
1475 	}
1476 }
1477 
1478 static void
1479 ampdu_tx_setup(struct ieee80211_tx_ampdu *tap)
1480 {
1481 	callout_init(&tap->txa_timer, CALLOUT_MPSAFE);
1482 	tap->txa_flags |= IEEE80211_AGGR_SETUP;
1483 }
1484 
1485 static void
1486 ampdu_tx_stop(struct ieee80211_tx_ampdu *tap)
1487 {
1488 	struct ieee80211_node *ni = tap->txa_ni;
1489 	struct ieee80211com *ic = ni->ni_ic;
1490 
1491 	KASSERT(tap->txa_flags & IEEE80211_AGGR_SETUP,
1492 	    ("txa_flags 0x%x ac %d", tap->txa_flags, tap->txa_ac));
1493 
1494 	/*
1495 	 * Stop BA stream if setup so driver has a chance
1496 	 * to reclaim any resources it might have allocated.
1497 	 */
1498 	ic->ic_addba_stop(ni, tap);
1499 	/*
1500 	 * Stop any pending BAR transmit.
1501 	 */
1502 	bar_stop_timer(tap);
1503 
1504 	tap->txa_lastsample = 0;
1505 	tap->txa_avgpps = 0;
1506 	/* NB: clearing NAK means we may re-send ADDBA */
1507 	tap->txa_flags &= ~(IEEE80211_AGGR_SETUP | IEEE80211_AGGR_NAK);
1508 }
1509 
1510 static void
1511 addba_timeout(void *arg)
1512 {
1513 	struct ieee80211_tx_ampdu *tap = arg;
1514 
1515 	/* XXX ? */
1516 	tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1517 	tap->txa_attempts++;
1518 }
1519 
1520 static void
1521 addba_start_timeout(struct ieee80211_tx_ampdu *tap)
1522 {
1523 	/* XXX use CALLOUT_PENDING instead? */
1524 	callout_reset(&tap->txa_timer, ieee80211_addba_timeout,
1525 	    addba_timeout, tap);
1526 	tap->txa_flags |= IEEE80211_AGGR_XCHGPEND;
1527 	tap->txa_nextrequest = ticks + ieee80211_addba_timeout;
1528 }
1529 
1530 static void
1531 addba_stop_timeout(struct ieee80211_tx_ampdu *tap)
1532 {
1533 	/* XXX use CALLOUT_PENDING instead? */
1534 	if (tap->txa_flags & IEEE80211_AGGR_XCHGPEND) {
1535 		callout_stop(&tap->txa_timer);
1536 		tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1537 	}
1538 }
1539 
1540 /*
1541  * Default method for requesting A-MPDU tx aggregation.
1542  * We setup the specified state block and start a timer
1543  * to wait for an ADDBA response frame.
1544  */
1545 static int
1546 ieee80211_addba_request(struct ieee80211_node *ni,
1547 	struct ieee80211_tx_ampdu *tap,
1548 	int dialogtoken, int baparamset, int batimeout)
1549 {
1550 	int bufsiz;
1551 
1552 	/* XXX locking */
1553 	tap->txa_token = dialogtoken;
1554 	tap->txa_flags |= IEEE80211_AGGR_IMMEDIATE;
1555 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1556 	tap->txa_wnd = (bufsiz == 0) ?
1557 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1558 	addba_start_timeout(tap);
1559 	return 1;
1560 }
1561 
1562 /*
1563  * Default method for processing an A-MPDU tx aggregation
1564  * response.  We shutdown any pending timer and update the
1565  * state block according to the reply.
1566  */
1567 static int
1568 ieee80211_addba_response(struct ieee80211_node *ni,
1569 	struct ieee80211_tx_ampdu *tap,
1570 	int status, int baparamset, int batimeout)
1571 {
1572 	int bufsiz, tid;
1573 
1574 	/* XXX locking */
1575 	addba_stop_timeout(tap);
1576 	if (status == IEEE80211_STATUS_SUCCESS) {
1577 		bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1578 		/* XXX override our request? */
1579 		tap->txa_wnd = (bufsiz == 0) ?
1580 		    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1581 		/* XXX AC/TID */
1582 		tid = MS(baparamset, IEEE80211_BAPS_TID);
1583 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
1584 		tap->txa_attempts = 0;
1585 	} else {
1586 		/* mark tid so we don't try again */
1587 		tap->txa_flags |= IEEE80211_AGGR_NAK;
1588 	}
1589 	return 1;
1590 }
1591 
1592 /*
1593  * Default method for stopping A-MPDU tx aggregation.
1594  * Any timer is cleared and we drain any pending frames.
1595  */
1596 static void
1597 ieee80211_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
1598 {
1599 	/* XXX locking */
1600 	addba_stop_timeout(tap);
1601 	if (tap->txa_flags & IEEE80211_AGGR_RUNNING) {
1602 		/* XXX clear aggregation queue */
1603 		tap->txa_flags &= ~IEEE80211_AGGR_RUNNING;
1604 	}
1605 	tap->txa_attempts = 0;
1606 }
1607 
1608 /*
1609  * Process a received action frame using the default aggregation
1610  * policy.  We intercept ADDBA-related frames and use them to
1611  * update our aggregation state.  All other frames are passed up
1612  * for processing by ieee80211_recv_action.
1613  */
1614 static int
1615 ht_recv_action_ba_addba_request(struct ieee80211_node *ni,
1616 	const struct ieee80211_frame *wh,
1617 	const uint8_t *frm, const uint8_t *efrm)
1618 {
1619 	struct ieee80211com *ic = ni->ni_ic;
1620 	struct ieee80211vap *vap = ni->ni_vap;
1621 	struct ieee80211_rx_ampdu *rap;
1622 	uint8_t dialogtoken;
1623 	uint16_t baparamset, batimeout, baseqctl;
1624 	uint16_t args[4];
1625 	int tid;
1626 
1627 	dialogtoken = frm[2];
1628 	baparamset = LE_READ_2(frm+3);
1629 	batimeout = LE_READ_2(frm+5);
1630 	baseqctl = LE_READ_2(frm+7);
1631 
1632 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1633 
1634 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1635 	    "recv ADDBA request: dialogtoken %u baparamset 0x%x "
1636 	    "(tid %d bufsiz %d) batimeout %d baseqctl %d:%d",
1637 	    dialogtoken, baparamset,
1638 	    tid, MS(baparamset, IEEE80211_BAPS_BUFSIZ),
1639 	    batimeout,
1640 	    MS(baseqctl, IEEE80211_BASEQ_START),
1641 	    MS(baseqctl, IEEE80211_BASEQ_FRAG));
1642 
1643 	rap = &ni->ni_rx_ampdu[tid];
1644 
1645 	/* Send ADDBA response */
1646 	args[0] = dialogtoken;
1647 	/*
1648 	 * NB: We ack only if the sta associated with HT and
1649 	 * the ap is configured to do AMPDU rx (the latter
1650 	 * violates the 11n spec and is mostly for testing).
1651 	 */
1652 	if ((ni->ni_flags & IEEE80211_NODE_AMPDU_RX) &&
1653 	    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_RX)) {
1654 		/* XXX handle ampdu_rx_start failure */
1655 		ic->ic_ampdu_rx_start(ni, rap,
1656 		    baparamset, batimeout, baseqctl);
1657 
1658 		args[1] = IEEE80211_STATUS_SUCCESS;
1659 	} else {
1660 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1661 		    ni, "reject ADDBA request: %s",
1662 		    ni->ni_flags & IEEE80211_NODE_AMPDU_RX ?
1663 		       "administratively disabled" :
1664 		       "not negotiated for station");
1665 		vap->iv_stats.is_addba_reject++;
1666 		args[1] = IEEE80211_STATUS_UNSPECIFIED;
1667 	}
1668 	/* XXX honor rap flags? */
1669 	args[2] = IEEE80211_BAPS_POLICY_IMMEDIATE
1670 		| SM(tid, IEEE80211_BAPS_TID)
1671 		| SM(rap->rxa_wnd, IEEE80211_BAPS_BUFSIZ)
1672 		;
1673 	args[3] = 0;
1674 	ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1675 		IEEE80211_ACTION_BA_ADDBA_RESPONSE, args);
1676 	return 0;
1677 }
1678 
1679 static int
1680 ht_recv_action_ba_addba_response(struct ieee80211_node *ni,
1681 	const struct ieee80211_frame *wh,
1682 	const uint8_t *frm, const uint8_t *efrm)
1683 {
1684 	struct ieee80211com *ic = ni->ni_ic;
1685 	struct ieee80211vap *vap = ni->ni_vap;
1686 	struct ieee80211_tx_ampdu *tap;
1687 	uint8_t dialogtoken, policy;
1688 	uint16_t baparamset, batimeout, code;
1689 	int tid, ac, bufsiz;
1690 
1691 	dialogtoken = frm[2];
1692 	code = LE_READ_2(frm+3);
1693 	baparamset = LE_READ_2(frm+5);
1694 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1695 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1696 	policy = MS(baparamset, IEEE80211_BAPS_POLICY);
1697 	batimeout = LE_READ_2(frm+7);
1698 
1699 	ac = TID_TO_WME_AC(tid);
1700 	tap = &ni->ni_tx_ampdu[ac];
1701 	if ((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
1702 		IEEE80211_DISCARD_MAC(vap,
1703 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1704 		    ni->ni_macaddr, "ADDBA response",
1705 		    "no pending ADDBA, tid %d dialogtoken %u "
1706 		    "code %d", tid, dialogtoken, code);
1707 		vap->iv_stats.is_addba_norequest++;
1708 		return 0;
1709 	}
1710 	if (dialogtoken != tap->txa_token) {
1711 		IEEE80211_DISCARD_MAC(vap,
1712 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1713 		    ni->ni_macaddr, "ADDBA response",
1714 		    "dialogtoken mismatch: waiting for %d, "
1715 		    "received %d, tid %d code %d",
1716 		    tap->txa_token, dialogtoken, tid, code);
1717 		vap->iv_stats.is_addba_badtoken++;
1718 		return 0;
1719 	}
1720 	/* NB: assumes IEEE80211_AGGR_IMMEDIATE is 1 */
1721 	if (policy != (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE)) {
1722 		IEEE80211_DISCARD_MAC(vap,
1723 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1724 		    ni->ni_macaddr, "ADDBA response",
1725 		    "policy mismatch: expecting %s, "
1726 		    "received %s, tid %d code %d",
1727 		    tap->txa_flags & IEEE80211_AGGR_IMMEDIATE,
1728 		    policy, tid, code);
1729 		vap->iv_stats.is_addba_badpolicy++;
1730 		return 0;
1731 	}
1732 #if 0
1733 	/* XXX we take MIN in ieee80211_addba_response */
1734 	if (bufsiz > IEEE80211_AGGR_BAWMAX) {
1735 		IEEE80211_DISCARD_MAC(vap,
1736 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1737 		    ni->ni_macaddr, "ADDBA response",
1738 		    "BA window too large: max %d, "
1739 		    "received %d, tid %d code %d",
1740 		    bufsiz, IEEE80211_AGGR_BAWMAX, tid, code);
1741 		vap->iv_stats.is_addba_badbawinsize++;
1742 		return 0;
1743 	}
1744 #endif
1745 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1746 	    "recv ADDBA response: dialogtoken %u code %d "
1747 	    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d",
1748 	    dialogtoken, code, baparamset, tid, bufsiz,
1749 	    batimeout);
1750 	ic->ic_addba_response(ni, tap, code, baparamset, batimeout);
1751 	return 0;
1752 }
1753 
1754 static int
1755 ht_recv_action_ba_delba(struct ieee80211_node *ni,
1756 	const struct ieee80211_frame *wh,
1757 	const uint8_t *frm, const uint8_t *efrm)
1758 {
1759 	struct ieee80211com *ic = ni->ni_ic;
1760 	struct ieee80211_rx_ampdu *rap;
1761 	struct ieee80211_tx_ampdu *tap;
1762 	uint16_t baparamset, code;
1763 	int tid, ac;
1764 
1765 	baparamset = LE_READ_2(frm+2);
1766 	code = LE_READ_2(frm+4);
1767 
1768 	tid = MS(baparamset, IEEE80211_DELBAPS_TID);
1769 
1770 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1771 	    "recv DELBA: baparamset 0x%x (tid %d initiator %d) "
1772 	    "code %d", baparamset, tid,
1773 	    MS(baparamset, IEEE80211_DELBAPS_INIT), code);
1774 
1775 	if ((baparamset & IEEE80211_DELBAPS_INIT) == 0) {
1776 		ac = TID_TO_WME_AC(tid);
1777 		tap = &ni->ni_tx_ampdu[ac];
1778 		ic->ic_addba_stop(ni, tap);
1779 	} else {
1780 		rap = &ni->ni_rx_ampdu[tid];
1781 		ic->ic_ampdu_rx_stop(ni, rap);
1782 	}
1783 	return 0;
1784 }
1785 
1786 static int
1787 ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
1788 	const struct ieee80211_frame *wh,
1789 	const uint8_t *frm, const uint8_t *efrm)
1790 {
1791 	int chw;
1792 
1793 	chw = (frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040) ? 40 : 20;
1794 
1795 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1796 	    "%s: HT txchwidth, width %d%s",
1797 	    __func__, chw, ni->ni_chw != chw ? "*" : "");
1798 	if (chw != ni->ni_chw) {
1799 		ni->ni_chw = chw;
1800 		/* XXX notify on change */
1801 	}
1802 	return 0;
1803 }
1804 
1805 static int
1806 ht_recv_action_ht_mimopwrsave(struct ieee80211_node *ni,
1807 	const struct ieee80211_frame *wh,
1808 	const uint8_t *frm, const uint8_t *efrm)
1809 {
1810 	const struct ieee80211_action_ht_mimopowersave *mps =
1811 	    (const struct ieee80211_action_ht_mimopowersave *) frm;
1812 
1813 	/* XXX check iv_htcaps */
1814 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_ENA)
1815 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1816 	else
1817 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1818 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_MODE)
1819 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1820 	else
1821 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1822 	/* XXX notify on change */
1823 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1824 	    "%s: HT MIMO PS (%s%s)", __func__,
1825 	    (ni->ni_flags & IEEE80211_NODE_MIMO_PS) ?  "on" : "off",
1826 	    (ni->ni_flags & IEEE80211_NODE_MIMO_RTS) ?  "+rts" : ""
1827 	);
1828 	return 0;
1829 }
1830 
1831 /*
1832  * Transmit processing.
1833  */
1834 
1835 /*
1836  * Check if A-MPDU should be requested/enabled for a stream.
1837  * We require a traffic rate above a per-AC threshold and we
1838  * also handle backoff from previous failed attempts.
1839  *
1840  * Drivers may override this method to bring in information
1841  * such as link state conditions in making the decision.
1842  */
1843 static int
1844 ieee80211_ampdu_enable(struct ieee80211_node *ni,
1845 	struct ieee80211_tx_ampdu *tap)
1846 {
1847 	struct ieee80211vap *vap = ni->ni_vap;
1848 
1849 	if (tap->txa_avgpps < vap->iv_ampdu_mintraffic[tap->txa_ac])
1850 		return 0;
1851 	/* XXX check rssi? */
1852 	if (tap->txa_attempts >= ieee80211_addba_maxtries &&
1853 	    ticks < tap->txa_nextrequest) {
1854 		/*
1855 		 * Don't retry too often; txa_nextrequest is set
1856 		 * to the minimum interval we'll retry after
1857 		 * ieee80211_addba_maxtries failed attempts are made.
1858 		 */
1859 		return 0;
1860 	}
1861 	IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1862 	    "enable AMPDU on %s, avgpps %d pkts %d",
1863 	    ieee80211_wme_acnames[tap->txa_ac], tap->txa_avgpps, tap->txa_pkts);
1864 	return 1;
1865 }
1866 
1867 /*
1868  * Request A-MPDU tx aggregation.  Setup local state and
1869  * issue an ADDBA request.  BA use will only happen after
1870  * the other end replies with ADDBA response.
1871  */
1872 int
1873 ieee80211_ampdu_request(struct ieee80211_node *ni,
1874 	struct ieee80211_tx_ampdu *tap)
1875 {
1876 	struct ieee80211com *ic = ni->ni_ic;
1877 	uint16_t args[4];
1878 	int tid, dialogtoken;
1879 	static int tokens = 0;	/* XXX */
1880 
1881 	/* XXX locking */
1882 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
1883 		/* do deferred setup of state */
1884 		ampdu_tx_setup(tap);
1885 	}
1886 	/* XXX hack for not doing proper locking */
1887 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
1888 
1889 	dialogtoken = (tokens+1) % 63;		/* XXX */
1890 	tid = WME_AC_TO_TID(tap->txa_ac);
1891 	tap->txa_start = ni->ni_txseqs[tid];
1892 
1893 	args[0] = dialogtoken;
1894 	args[1]	= IEEE80211_BAPS_POLICY_IMMEDIATE
1895 		| SM(tid, IEEE80211_BAPS_TID)
1896 		| SM(IEEE80211_AGGR_BAWMAX, IEEE80211_BAPS_BUFSIZ)
1897 		;
1898 	args[2] = 0;	/* batimeout */
1899 	/* NB: do first so there's no race against reply */
1900 	if (!ic->ic_addba_request(ni, tap, dialogtoken, args[1], args[2])) {
1901 		/* unable to setup state, don't make request */
1902 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1903 		    ni, "%s: could not setup BA stream for AC %d",
1904 		    __func__, tap->txa_ac);
1905 		/* defer next try so we don't slam the driver with requests */
1906 		tap->txa_attempts = ieee80211_addba_maxtries;
1907 		/* NB: check in case driver wants to override */
1908 		if (tap->txa_nextrequest <= ticks)
1909 			tap->txa_nextrequest = ticks + ieee80211_addba_backoff;
1910 		return 0;
1911 	}
1912 	tokens = dialogtoken;			/* allocate token */
1913 	/* NB: after calling ic_addba_request so driver can set txa_start */
1914 	args[3] = SM(tap->txa_start, IEEE80211_BASEQ_START)
1915 		| SM(0, IEEE80211_BASEQ_FRAG)
1916 		;
1917 	return ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1918 		IEEE80211_ACTION_BA_ADDBA_REQUEST, args);
1919 }
1920 
1921 /*
1922  * Terminate an AMPDU tx stream.  State is reclaimed
1923  * and the peer notified with a DelBA Action frame.
1924  */
1925 void
1926 ieee80211_ampdu_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
1927 	int reason)
1928 {
1929 	struct ieee80211com *ic = ni->ni_ic;
1930 	struct ieee80211vap *vap = ni->ni_vap;
1931 	uint16_t args[4];
1932 
1933 	/* XXX locking */
1934 	tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
1935 	if (IEEE80211_AMPDU_RUNNING(tap)) {
1936 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1937 		    ni, "%s: stop BA stream for AC %d (reason %d)",
1938 		    __func__, tap->txa_ac, reason);
1939 		vap->iv_stats.is_ampdu_stop++;
1940 
1941 		ic->ic_addba_stop(ni, tap);
1942 		args[0] = WME_AC_TO_TID(tap->txa_ac);
1943 		args[1] = IEEE80211_DELBAPS_INIT;
1944 		args[2] = reason;			/* XXX reason code */
1945 		ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1946 			IEEE80211_ACTION_BA_DELBA, args);
1947 	} else {
1948 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1949 		    ni, "%s: BA stream for AC %d not running (reason %d)",
1950 		    __func__, tap->txa_ac, reason);
1951 		vap->iv_stats.is_ampdu_stop_failed++;
1952 	}
1953 }
1954 
1955 static void
1956 bar_timeout(void *arg)
1957 {
1958 	struct ieee80211_tx_ampdu *tap = arg;
1959 	struct ieee80211_node *ni = tap->txa_ni;
1960 
1961 	KASSERT((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0,
1962 	    ("bar/addba collision, flags 0x%x", tap->txa_flags));
1963 
1964 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1965 	    ni, "%s: tid %u flags 0x%x attempts %d", __func__,
1966 	    tap->txa_ac, tap->txa_flags, tap->txa_attempts);
1967 
1968 	/* guard against race with bar_tx_complete */
1969 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
1970 		return;
1971 	/* XXX ? */
1972 	if (tap->txa_attempts >= ieee80211_bar_maxtries)
1973 		ieee80211_ampdu_stop(ni, tap, IEEE80211_REASON_TIMEOUT);
1974 	else
1975 		ieee80211_send_bar(ni, tap, tap->txa_seqpending);
1976 }
1977 
1978 static void
1979 bar_start_timer(struct ieee80211_tx_ampdu *tap)
1980 {
1981 	callout_reset(&tap->txa_timer, ieee80211_bar_timeout, bar_timeout, tap);
1982 }
1983 
1984 static void
1985 bar_stop_timer(struct ieee80211_tx_ampdu *tap)
1986 {
1987 	callout_stop(&tap->txa_timer);
1988 }
1989 
1990 static void
1991 bar_tx_complete(struct ieee80211_node *ni, void *arg, int status)
1992 {
1993 	struct ieee80211_tx_ampdu *tap = arg;
1994 
1995 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
1996 	    ni, "%s: tid %u flags 0x%x pending %d status %d",
1997 	    __func__, tap->txa_ac, tap->txa_flags,
1998 	    callout_pending(&tap->txa_timer), status);
1999 
2000 	/* XXX locking */
2001 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) &&
2002 	    callout_pending(&tap->txa_timer)) {
2003 		struct ieee80211com *ic = ni->ni_ic;
2004 
2005 		if (status)		/* ACK'd */
2006 			bar_stop_timer(tap);
2007 		ic->ic_bar_response(ni, tap, status);
2008 		/* NB: just let timer expire so we pace requests */
2009 	}
2010 }
2011 
2012 static void
2013 ieee80211_bar_response(struct ieee80211_node *ni,
2014 	struct ieee80211_tx_ampdu *tap, int status)
2015 {
2016 
2017 	if (status != 0) {		/* got ACK */
2018 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2019 		    ni, "BAR moves BA win <%u:%u> (%u frames) txseq %u tid %u",
2020 		    tap->txa_start,
2021 		    IEEE80211_SEQ_ADD(tap->txa_start, tap->txa_wnd-1),
2022 		    tap->txa_qframes, tap->txa_seqpending,
2023 		    WME_AC_TO_TID(tap->txa_ac));
2024 
2025 		/* NB: timer already stopped in bar_tx_complete */
2026 		tap->txa_start = tap->txa_seqpending;
2027 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2028 	}
2029 }
2030 
2031 /*
2032  * Transmit a BAR frame to the specified node.  The
2033  * BAR contents are drawn from the supplied aggregation
2034  * state associated with the node.
2035  *
2036  * NB: we only handle immediate ACK w/ compressed bitmap.
2037  */
2038 int
2039 ieee80211_send_bar(struct ieee80211_node *ni,
2040 	struct ieee80211_tx_ampdu *tap, ieee80211_seq seq)
2041 {
2042 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2043 	struct ieee80211vap *vap = ni->ni_vap;
2044 	struct ieee80211com *ic = ni->ni_ic;
2045 	struct ieee80211_frame_bar *bar;
2046 	struct mbuf *m;
2047 	uint16_t barctl, barseqctl;
2048 	uint8_t *frm;
2049 	int tid, ret;
2050 
2051 	if ((tap->txa_flags & IEEE80211_AGGR_RUNNING) == 0) {
2052 		/* no ADDBA response, should not happen */
2053 		/* XXX stat+msg */
2054 		return EINVAL;
2055 	}
2056 	/* XXX locking */
2057 	bar_stop_timer(tap);
2058 
2059 	ieee80211_ref_node(ni);
2060 
2061 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom, sizeof(*bar));
2062 	if (m == NULL)
2063 		senderr(ENOMEM, is_tx_nobuf);
2064 
2065 	if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
2066 		m_freem(m);
2067 		senderr(ENOMEM, is_tx_nobuf);	/* XXX */
2068 		/* NOTREACHED */
2069 	}
2070 
2071 	bar = mtod(m, struct ieee80211_frame_bar *);
2072 	bar->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2073 		IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_BAR;
2074 	bar->i_fc[1] = 0;
2075 	IEEE80211_ADDR_COPY(bar->i_ra, ni->ni_macaddr);
2076 	IEEE80211_ADDR_COPY(bar->i_ta, vap->iv_myaddr);
2077 
2078 	tid = WME_AC_TO_TID(tap->txa_ac);
2079 	barctl 	= (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE ?
2080 			0 : IEEE80211_BAR_NOACK)
2081 		| IEEE80211_BAR_COMP
2082 		| SM(tid, IEEE80211_BAR_TID)
2083 		;
2084 	barseqctl = SM(seq, IEEE80211_BAR_SEQ_START);
2085 	/* NB: known to have proper alignment */
2086 	bar->i_ctl = htole16(barctl);
2087 	bar->i_seq = htole16(barseqctl);
2088 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_bar);
2089 
2090 	M_WME_SETAC(m, WME_AC_VO);
2091 
2092 	IEEE80211_NODE_STAT(ni, tx_mgmt);	/* XXX tx_ctl? */
2093 
2094 	/* XXX locking */
2095 	/* init/bump attempts counter */
2096 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2097 		tap->txa_attempts = 1;
2098 	else
2099 		tap->txa_attempts++;
2100 	tap->txa_seqpending = seq;
2101 	tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2102 
2103 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2104 	    ni, "send BAR: tid %u ctl 0x%x start %u (attempt %d)",
2105 	    tid, barctl, seq, tap->txa_attempts);
2106 
2107 	ret = ic->ic_raw_xmit(ni, m, NULL);
2108 	if (ret != 0) {
2109 		/* xmit failed, clear state flag */
2110 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2111 		goto bad;
2112 	}
2113 	/* XXX hack against tx complete happening before timer is started */
2114 	if (tap->txa_flags & IEEE80211_AGGR_BARPEND)
2115 		bar_start_timer(tap);
2116 	return 0;
2117 bad:
2118 	ieee80211_free_node(ni);
2119 	return ret;
2120 #undef senderr
2121 }
2122 
2123 static int
2124 ht_action_output(struct ieee80211_node *ni, struct mbuf *m)
2125 {
2126 	struct ieee80211_bpf_params params;
2127 
2128 	memset(&params, 0, sizeof(params));
2129 	params.ibp_pri = WME_AC_VO;
2130 	params.ibp_rate0 = ni->ni_txparms->mgmtrate;
2131 	/* NB: we know all frames are unicast */
2132 	params.ibp_try0 = ni->ni_txparms->maxretry;
2133 	params.ibp_power = ni->ni_txpower;
2134 	return ieee80211_mgmt_output(ni, m, IEEE80211_FC0_SUBTYPE_ACTION,
2135 	     &params);
2136 }
2137 
2138 #define	ADDSHORT(frm, v) do {			\
2139 	frm[0] = (v) & 0xff;			\
2140 	frm[1] = (v) >> 8;			\
2141 	frm += 2;				\
2142 } while (0)
2143 
2144 /*
2145  * Send an action management frame.  The arguments are stuff
2146  * into a frame without inspection; the caller is assumed to
2147  * prepare them carefully (e.g. based on the aggregation state).
2148  */
2149 static int
2150 ht_send_action_ba_addba(struct ieee80211_node *ni,
2151 	int category, int action, void *arg0)
2152 {
2153 	struct ieee80211vap *vap = ni->ni_vap;
2154 	struct ieee80211com *ic = ni->ni_ic;
2155 	uint16_t *args = arg0;
2156 	struct mbuf *m;
2157 	uint8_t *frm;
2158 
2159 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2160 	    "send ADDBA %s: dialogtoken %d "
2161 	    "baparamset 0x%x (tid %d) batimeout 0x%x baseqctl 0x%x",
2162 	    (action == IEEE80211_ACTION_BA_ADDBA_REQUEST) ?
2163 		"request" : "response",
2164 	    args[0], args[1], MS(args[1], IEEE80211_BAPS_TID),
2165 	    args[2], args[3]);
2166 
2167 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2168 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2169 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2170 	ieee80211_ref_node(ni);
2171 
2172 	m = ieee80211_getmgtframe(&frm,
2173 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2174 	    sizeof(uint16_t)	/* action+category */
2175 	    /* XXX may action payload */
2176 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2177 	);
2178 	if (m != NULL) {
2179 		*frm++ = category;
2180 		*frm++ = action;
2181 		*frm++ = args[0];		/* dialog token */
2182 		ADDSHORT(frm, args[1]);		/* baparamset */
2183 		ADDSHORT(frm, args[2]);		/* batimeout */
2184 		if (action == IEEE80211_ACTION_BA_ADDBA_REQUEST)
2185 			ADDSHORT(frm, args[3]);	/* baseqctl */
2186 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2187 		return ht_action_output(ni, m);
2188 	} else {
2189 		vap->iv_stats.is_tx_nobuf++;
2190 		ieee80211_free_node(ni);
2191 		return ENOMEM;
2192 	}
2193 }
2194 
2195 static int
2196 ht_send_action_ba_delba(struct ieee80211_node *ni,
2197 	int category, int action, void *arg0)
2198 {
2199 	struct ieee80211vap *vap = ni->ni_vap;
2200 	struct ieee80211com *ic = ni->ni_ic;
2201 	uint16_t *args = arg0;
2202 	struct mbuf *m;
2203 	uint16_t baparamset;
2204 	uint8_t *frm;
2205 
2206 	baparamset = SM(args[0], IEEE80211_DELBAPS_TID)
2207 		   | args[1]
2208 		   ;
2209 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2210 	    "send DELBA action: tid %d, initiator %d reason %d",
2211 	    args[0], args[1], args[2]);
2212 
2213 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2214 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2215 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2216 	ieee80211_ref_node(ni);
2217 
2218 	m = ieee80211_getmgtframe(&frm,
2219 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2220 	    sizeof(uint16_t)	/* action+category */
2221 	    /* XXX may action payload */
2222 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2223 	);
2224 	if (m != NULL) {
2225 		*frm++ = category;
2226 		*frm++ = action;
2227 		ADDSHORT(frm, baparamset);
2228 		ADDSHORT(frm, args[2]);		/* reason code */
2229 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2230 		return ht_action_output(ni, m);
2231 	} else {
2232 		vap->iv_stats.is_tx_nobuf++;
2233 		ieee80211_free_node(ni);
2234 		return ENOMEM;
2235 	}
2236 }
2237 
2238 static int
2239 ht_send_action_ht_txchwidth(struct ieee80211_node *ni,
2240 	int category, int action, void *arg0)
2241 {
2242 	struct ieee80211vap *vap = ni->ni_vap;
2243 	struct ieee80211com *ic = ni->ni_ic;
2244 	struct mbuf *m;
2245 	uint8_t *frm;
2246 
2247 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2248 	    "send HT txchwidth: width %d",
2249 	    IEEE80211_IS_CHAN_HT40(ni->ni_chan) ? 40 : 20);
2250 
2251 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2252 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2253 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2254 	ieee80211_ref_node(ni);
2255 
2256 	m = ieee80211_getmgtframe(&frm,
2257 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2258 	    sizeof(uint16_t)	/* action+category */
2259 	    /* XXX may action payload */
2260 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2261 	);
2262 	if (m != NULL) {
2263 		*frm++ = category;
2264 		*frm++ = action;
2265 		*frm++ = IEEE80211_IS_CHAN_HT40(ni->ni_chan) ?
2266 			IEEE80211_A_HT_TXCHWIDTH_2040 :
2267 			IEEE80211_A_HT_TXCHWIDTH_20;
2268 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2269 		return ht_action_output(ni, m);
2270 	} else {
2271 		vap->iv_stats.is_tx_nobuf++;
2272 		ieee80211_free_node(ni);
2273 		return ENOMEM;
2274 	}
2275 }
2276 #undef ADDSHORT
2277 
2278 /*
2279  * Construct the MCS bit mask for inclusion
2280  * in an HT information element.
2281  */
2282 static void
2283 ieee80211_set_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2284 {
2285 	int i;
2286 
2287 	for (i = 0; i < rs->rs_nrates; i++) {
2288 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2289 		if (r < IEEE80211_HTRATE_MAXSIZE) {	/* XXX? */
2290 			/* NB: this assumes a particular implementation */
2291 			setbit(frm, r);
2292 		}
2293 	}
2294 }
2295 
2296 /*
2297  * Add body of an HTCAP information element.
2298  */
2299 static uint8_t *
2300 ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
2301 {
2302 #define	ADDSHORT(frm, v) do {			\
2303 	frm[0] = (v) & 0xff;			\
2304 	frm[1] = (v) >> 8;			\
2305 	frm += 2;				\
2306 } while (0)
2307 	struct ieee80211vap *vap = ni->ni_vap;
2308 	uint16_t caps;
2309 	int rxmax, density;
2310 
2311 	/* HT capabilities */
2312 	caps = vap->iv_htcaps & 0xffff;
2313 	/*
2314 	 * Note channel width depends on whether we are operating as
2315 	 * a sta or not.  When operating as a sta we are generating
2316 	 * a request based on our desired configuration.  Otherwise
2317 	 * we are operational and the channel attributes identify
2318 	 * how we've been setup (which might be different if a fixed
2319 	 * channel is specified).
2320 	 */
2321 	if (vap->iv_opmode == IEEE80211_M_STA) {
2322 		/* override 20/40 use based on config */
2323 		if (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)
2324 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2325 		else
2326 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2327 		/* use advertised setting (XXX locally constraint) */
2328 		rxmax = MS(ni->ni_htparam, IEEE80211_HTCAP_MAXRXAMPDU);
2329 		density = MS(ni->ni_htparam, IEEE80211_HTCAP_MPDUDENSITY);
2330 	} else {
2331 		/* override 20/40 use based on current channel */
2332 		if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2333 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2334 		else
2335 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2336 		rxmax = vap->iv_ampdu_rxmax;
2337 		density = vap->iv_ampdu_density;
2338 	}
2339 	/* adjust short GI based on channel and config */
2340 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20) == 0)
2341 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
2342 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40) == 0 ||
2343 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
2344 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
2345 	ADDSHORT(frm, caps);
2346 
2347 	/* HT parameters */
2348 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
2349 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
2350 	     ;
2351 	frm++;
2352 
2353 	/* pre-zero remainder of ie */
2354 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
2355 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
2356 
2357 	/* supported MCS set */
2358 	/*
2359 	 * XXX it would better to get the rate set from ni_htrates
2360 	 * so we can restrict it but for sta mode ni_htrates isn't
2361 	 * setup when we're called to form an AssocReq frame so for
2362 	 * now we're restricted to the default HT rate set.
2363 	 */
2364 	ieee80211_set_htrates(frm, &ieee80211_rateset_11n);
2365 
2366 	frm += sizeof(struct ieee80211_ie_htcap) -
2367 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
2368 	return frm;
2369 #undef ADDSHORT
2370 }
2371 
2372 /*
2373  * Add 802.11n HT capabilities information element
2374  */
2375 uint8_t *
2376 ieee80211_add_htcap(uint8_t *frm, struct ieee80211_node *ni)
2377 {
2378 	frm[0] = IEEE80211_ELEMID_HTCAP;
2379 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
2380 	return ieee80211_add_htcap_body(frm + 2, ni);
2381 }
2382 
2383 /*
2384  * Add Broadcom OUI wrapped standard HTCAP ie; this is
2385  * used for compatibility w/ pre-draft implementations.
2386  */
2387 uint8_t *
2388 ieee80211_add_htcap_vendor(uint8_t *frm, struct ieee80211_node *ni)
2389 {
2390 	frm[0] = IEEE80211_ELEMID_VENDOR;
2391 	frm[1] = 4 + sizeof(struct ieee80211_ie_htcap) - 2;
2392 	frm[2] = (BCM_OUI >> 0) & 0xff;
2393 	frm[3] = (BCM_OUI >> 8) & 0xff;
2394 	frm[4] = (BCM_OUI >> 16) & 0xff;
2395 	frm[5] = BCM_OUI_HTCAP;
2396 	return ieee80211_add_htcap_body(frm + 6, ni);
2397 }
2398 
2399 /*
2400  * Construct the MCS bit mask of basic rates
2401  * for inclusion in an HT information element.
2402  */
2403 static void
2404 ieee80211_set_basic_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2405 {
2406 	int i;
2407 
2408 	for (i = 0; i < rs->rs_nrates; i++) {
2409 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2410 		if ((rs->rs_rates[i] & IEEE80211_RATE_BASIC) &&
2411 		    r < IEEE80211_HTRATE_MAXSIZE) {
2412 			/* NB: this assumes a particular implementation */
2413 			setbit(frm, r);
2414 		}
2415 	}
2416 }
2417 
2418 /*
2419  * Update the HTINFO ie for a beacon frame.
2420  */
2421 void
2422 ieee80211_ht_update_beacon(struct ieee80211vap *vap,
2423 	struct ieee80211_beacon_offsets *bo)
2424 {
2425 #define	PROTMODE	(IEEE80211_HTINFO_OPMODE|IEEE80211_HTINFO_NONHT_PRESENT)
2426 	const struct ieee80211_channel *bsschan = vap->iv_bss->ni_chan;
2427 	struct ieee80211com *ic = vap->iv_ic;
2428 	struct ieee80211_ie_htinfo *ht =
2429 	   (struct ieee80211_ie_htinfo *) bo->bo_htinfo;
2430 
2431 	/* XXX only update on channel change */
2432 	ht->hi_ctrlchannel = ieee80211_chan2ieee(ic, bsschan);
2433 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2434 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PERM;
2435 	else
2436 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PROH;
2437 	if (IEEE80211_IS_CHAN_HT40U(bsschan))
2438 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2439 	else if (IEEE80211_IS_CHAN_HT40D(bsschan))
2440 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2441 	else
2442 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_NONE;
2443 	if (IEEE80211_IS_CHAN_HT40(bsschan))
2444 		ht->hi_byte1 |= IEEE80211_HTINFO_TXWIDTH_2040;
2445 
2446 	/* protection mode */
2447 	ht->hi_byte2 = (ht->hi_byte2 &~ PROTMODE) | ic->ic_curhtprotmode;
2448 
2449 	/* XXX propagate to vendor ie's */
2450 #undef PROTMODE
2451 }
2452 
2453 /*
2454  * Add body of an HTINFO information element.
2455  *
2456  * NB: We don't use struct ieee80211_ie_htinfo because we can
2457  * be called to fillin both a standard ie and a compat ie that
2458  * has a vendor OUI at the front.
2459  */
2460 static uint8_t *
2461 ieee80211_add_htinfo_body(uint8_t *frm, struct ieee80211_node *ni)
2462 {
2463 	struct ieee80211vap *vap = ni->ni_vap;
2464 	struct ieee80211com *ic = ni->ni_ic;
2465 
2466 	/* pre-zero remainder of ie */
2467 	memset(frm, 0, sizeof(struct ieee80211_ie_htinfo) - 2);
2468 
2469 	/* primary/control channel center */
2470 	*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2471 
2472 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2473 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PERM;
2474 	else
2475 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PROH;
2476 	if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
2477 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2478 	else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
2479 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2480 	else
2481 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_NONE;
2482 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2483 		frm[0] |= IEEE80211_HTINFO_TXWIDTH_2040;
2484 
2485 	frm[1] = ic->ic_curhtprotmode;
2486 
2487 	frm += 5;
2488 
2489 	/* basic MCS set */
2490 	ieee80211_set_basic_htrates(frm, &ni->ni_htrates);
2491 	frm += sizeof(struct ieee80211_ie_htinfo) -
2492 		__offsetof(struct ieee80211_ie_htinfo, hi_basicmcsset);
2493 	return frm;
2494 }
2495 
2496 /*
2497  * Add 802.11n HT information information element.
2498  */
2499 uint8_t *
2500 ieee80211_add_htinfo(uint8_t *frm, struct ieee80211_node *ni)
2501 {
2502 	frm[0] = IEEE80211_ELEMID_HTINFO;
2503 	frm[1] = sizeof(struct ieee80211_ie_htinfo) - 2;
2504 	return ieee80211_add_htinfo_body(frm + 2, ni);
2505 }
2506 
2507 /*
2508  * Add Broadcom OUI wrapped standard HTINFO ie; this is
2509  * used for compatibility w/ pre-draft implementations.
2510  */
2511 uint8_t *
2512 ieee80211_add_htinfo_vendor(uint8_t *frm, struct ieee80211_node *ni)
2513 {
2514 	frm[0] = IEEE80211_ELEMID_VENDOR;
2515 	frm[1] = 4 + sizeof(struct ieee80211_ie_htinfo) - 2;
2516 	frm[2] = (BCM_OUI >> 0) & 0xff;
2517 	frm[3] = (BCM_OUI >> 8) & 0xff;
2518 	frm[4] = (BCM_OUI >> 16) & 0xff;
2519 	frm[5] = BCM_OUI_HTINFO;
2520 	return ieee80211_add_htinfo_body(frm + 6, ni);
2521 }
2522