xref: /freebsd/sys/net80211/ieee80211_superg.c (revision f677a9e2672665f4eb3dd4111c07ee8f1f954262)
1 /*-
2  * Copyright (c) 2002-2009 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 __FBSDID("$FreeBSD$");
28 
29 #include "opt_wlan.h"
30 
31 #ifdef	IEEE80211_SUPPORT_SUPERG
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/mbuf.h>
36 #include <sys/kernel.h>
37 #include <sys/endian.h>
38 
39 #include <sys/socket.h>
40 
41 #include <net/bpf.h>
42 #include <net/ethernet.h>
43 #include <net/if.h>
44 #include <net/if_llc.h>
45 #include <net/if_media.h>
46 
47 #include <net80211/ieee80211_var.h>
48 #include <net80211/ieee80211_input.h>
49 #include <net80211/ieee80211_phy.h>
50 #include <net80211/ieee80211_superg.h>
51 
52 /*
53  * Atheros fast-frame encapsulation format.
54  * FF max payload:
55  * 802.2 + FFHDR + HPAD + 802.3 + 802.2 + 1500 + SPAD + 802.3 + 802.2 + 1500:
56  *   8   +   4   +  4   +   14  +   8   + 1500 +  6   +   14  +   8   + 1500
57  * = 3066
58  */
59 /* fast frame header is 32-bits */
60 #define	ATH_FF_PROTO	0x0000003f	/* protocol */
61 #define	ATH_FF_PROTO_S	0
62 #define	ATH_FF_FTYPE	0x000000c0	/* frame type */
63 #define	ATH_FF_FTYPE_S	6
64 #define	ATH_FF_HLEN32	0x00000300	/* optional hdr length */
65 #define	ATH_FF_HLEN32_S	8
66 #define	ATH_FF_SEQNUM	0x001ffc00	/* sequence number */
67 #define	ATH_FF_SEQNUM_S	10
68 #define	ATH_FF_OFFSET	0xffe00000	/* offset to 2nd payload */
69 #define	ATH_FF_OFFSET_S	21
70 
71 #define	ATH_FF_MAX_HDR_PAD	4
72 #define	ATH_FF_MAX_SEP_PAD	6
73 #define	ATH_FF_MAX_HDR		30
74 
75 #define	ATH_FF_PROTO_L2TUNNEL	0	/* L2 tunnel protocol */
76 #define	ATH_FF_ETH_TYPE		0x88bd	/* Ether type for encapsulated frames */
77 #define	ATH_FF_SNAP_ORGCODE_0	0x00
78 #define	ATH_FF_SNAP_ORGCODE_1	0x03
79 #define	ATH_FF_SNAP_ORGCODE_2	0x7f
80 
81 #define	ATH_FF_TXQMIN	2		/* min txq depth for staging */
82 #define	ATH_FF_TXQMAX	50		/* maximum # of queued frames allowed */
83 #define	ATH_FF_STAGEMAX	5		/* max waiting period for staged frame*/
84 
85 #define	ETHER_HEADER_COPY(dst, src) \
86 	memcpy(dst, src, sizeof(struct ether_header))
87 
88 static	int ieee80211_ffppsmin = 2;	/* pps threshold for ff aggregation */
89 SYSCTL_INT(_net_wlan, OID_AUTO, ffppsmin, CTLTYPE_INT | CTLFLAG_RW,
90 	&ieee80211_ffppsmin, 0, "min packet rate before fast-frame staging");
91 static	int ieee80211_ffagemax = -1;	/* max time frames held on stage q */
92 SYSCTL_PROC(_net_wlan, OID_AUTO, ffagemax, CTLTYPE_INT | CTLFLAG_RW,
93 	&ieee80211_ffagemax, 0, ieee80211_sysctl_msecs_ticks, "I",
94 	"max hold time for fast-frame staging (ms)");
95 
96 void
97 ieee80211_superg_attach(struct ieee80211com *ic)
98 {
99 	struct ieee80211_superg *sg;
100 
101 	if (ic->ic_caps & IEEE80211_C_FF) {
102 		sg = (struct ieee80211_superg *) malloc(
103 		     sizeof(struct ieee80211_superg), M_80211_VAP,
104 		     M_NOWAIT | M_ZERO);
105 		if (sg == NULL) {
106 			printf("%s: cannot allocate SuperG state block\n",
107 			    __func__);
108 			return;
109 		}
110 		ic->ic_superg = sg;
111 	}
112 	ieee80211_ffagemax = msecs_to_ticks(150);
113 }
114 
115 void
116 ieee80211_superg_detach(struct ieee80211com *ic)
117 {
118 	if (ic->ic_superg != NULL) {
119 		free(ic->ic_superg, M_80211_VAP);
120 		ic->ic_superg = NULL;
121 	}
122 }
123 
124 void
125 ieee80211_superg_vattach(struct ieee80211vap *vap)
126 {
127 	struct ieee80211com *ic = vap->iv_ic;
128 
129 	if (ic->ic_superg == NULL)	/* NB: can't do fast-frames w/o state */
130 		vap->iv_caps &= ~IEEE80211_C_FF;
131 	if (vap->iv_caps & IEEE80211_C_FF)
132 		vap->iv_flags |= IEEE80211_F_FF;
133 	/* NB: we only implement sta mode */
134 	if (vap->iv_opmode == IEEE80211_M_STA &&
135 	    (vap->iv_caps & IEEE80211_C_TURBOP))
136 		vap->iv_flags |= IEEE80211_F_TURBOP;
137 }
138 
139 void
140 ieee80211_superg_vdetach(struct ieee80211vap *vap)
141 {
142 }
143 
144 #define	ATH_OUI_BYTES		0x00, 0x03, 0x7f
145 /*
146  * Add a WME information element to a frame.
147  */
148 uint8_t *
149 ieee80211_add_ath(uint8_t *frm, uint8_t caps, ieee80211_keyix defkeyix)
150 {
151 	static const struct ieee80211_ath_ie info = {
152 		.ath_id		= IEEE80211_ELEMID_VENDOR,
153 		.ath_len	= sizeof(struct ieee80211_ath_ie) - 2,
154 		.ath_oui	= { ATH_OUI_BYTES },
155 		.ath_oui_type	= ATH_OUI_TYPE,
156 		.ath_oui_subtype= ATH_OUI_SUBTYPE,
157 		.ath_version	= ATH_OUI_VERSION,
158 	};
159 	struct ieee80211_ath_ie *ath = (struct ieee80211_ath_ie *) frm;
160 
161 	memcpy(frm, &info, sizeof(info));
162 	ath->ath_capability = caps;
163 	if (defkeyix != IEEE80211_KEYIX_NONE) {
164 		ath->ath_defkeyix[0] = (defkeyix & 0xff);
165 		ath->ath_defkeyix[1] = ((defkeyix >> 8) & 0xff);
166 	} else {
167 		ath->ath_defkeyix[0] = 0xff;
168 		ath->ath_defkeyix[1] = 0x7f;
169 	}
170 	return frm + sizeof(info);
171 }
172 #undef ATH_OUI_BYTES
173 
174 uint8_t *
175 ieee80211_add_athcaps(uint8_t *frm, const struct ieee80211_node *bss)
176 {
177 	const struct ieee80211vap *vap = bss->ni_vap;
178 
179 	return ieee80211_add_ath(frm,
180 	    vap->iv_flags & IEEE80211_F_ATHEROS,
181 	    ((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
182 	    bss->ni_authmode != IEEE80211_AUTH_8021X) ?
183 	    vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
184 }
185 
186 void
187 ieee80211_parse_ath(struct ieee80211_node *ni, uint8_t *ie)
188 {
189 	const struct ieee80211_ath_ie *ath =
190 		(const struct ieee80211_ath_ie *) ie;
191 
192 	ni->ni_ath_flags = ath->ath_capability;
193 	ni->ni_ath_defkeyix = LE_READ_2(&ath->ath_defkeyix);
194 }
195 
196 int
197 ieee80211_parse_athparams(struct ieee80211_node *ni, uint8_t *frm,
198 	const struct ieee80211_frame *wh)
199 {
200 	struct ieee80211vap *vap = ni->ni_vap;
201 	const struct ieee80211_ath_ie *ath;
202 	u_int len = frm[1];
203 	int capschanged;
204 	uint16_t defkeyix;
205 
206 	if (len < sizeof(struct ieee80211_ath_ie)-2) {
207 		IEEE80211_DISCARD_IE(vap,
208 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_SUPERG,
209 		    wh, "Atheros", "too short, len %u", len);
210 		return -1;
211 	}
212 	ath = (const struct ieee80211_ath_ie *)frm;
213 	capschanged = (ni->ni_ath_flags != ath->ath_capability);
214 	defkeyix = LE_READ_2(ath->ath_defkeyix);
215 	if (capschanged || defkeyix != ni->ni_ath_defkeyix) {
216 		ni->ni_ath_flags = ath->ath_capability;
217 		ni->ni_ath_defkeyix = defkeyix;
218 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
219 		    "ath ie change: new caps 0x%x defkeyix 0x%x",
220 		    ni->ni_ath_flags, ni->ni_ath_defkeyix);
221 	}
222 	if (IEEE80211_ATH_CAP(vap, ni, ATHEROS_CAP_TURBO_PRIME)) {
223 		uint16_t curflags, newflags;
224 
225 		/*
226 		 * Check for turbo mode switch.  Calculate flags
227 		 * for the new mode and effect the switch.
228 		 */
229 		newflags = curflags = vap->iv_ic->ic_bsschan->ic_flags;
230 		/* NB: BOOST is not in ic_flags, so get it from the ie */
231 		if (ath->ath_capability & ATHEROS_CAP_BOOST)
232 			newflags |= IEEE80211_CHAN_TURBO;
233 		else
234 			newflags &= ~IEEE80211_CHAN_TURBO;
235 		if (newflags != curflags)
236 			ieee80211_dturbo_switch(vap, newflags);
237 	}
238 	return capschanged;
239 }
240 
241 /*
242  * Decap the encapsulated frame pair and dispatch the first
243  * for delivery.  The second frame is returned for delivery
244  * via the normal path.
245  */
246 struct mbuf *
247 ieee80211_ff_decap(struct ieee80211_node *ni, struct mbuf *m)
248 {
249 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
250 #define	MS(x,f)	(((x) & f) >> f##_S)
251 	struct ieee80211vap *vap = ni->ni_vap;
252 	struct llc *llc;
253 	uint32_t ath;
254 	struct mbuf *n;
255 	int framelen;
256 
257 	/* NB: we assume caller does this check for us */
258 	KASSERT(IEEE80211_ATH_CAP(vap, ni, IEEE80211_NODE_FF),
259 	    ("ff not negotiated"));
260 	/*
261 	 * Check for fast-frame tunnel encapsulation.
262 	 */
263 	if (m->m_pkthdr.len < 3*FF_LLC_SIZE)
264 		return m;
265 	if (m->m_len < FF_LLC_SIZE &&
266 	    (m = m_pullup(m, FF_LLC_SIZE)) == NULL) {
267 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
268 		    ni->ni_macaddr, "fast-frame",
269 		    "%s", "m_pullup(llc) failed");
270 		vap->iv_stats.is_rx_tooshort++;
271 		return NULL;
272 	}
273 	llc = (struct llc *)(mtod(m, uint8_t *) +
274 	    sizeof(struct ether_header));
275 	if (llc->llc_snap.ether_type != htons(ATH_FF_ETH_TYPE))
276 		return m;
277 	m_adj(m, FF_LLC_SIZE);
278 	m_copydata(m, 0, sizeof(uint32_t), (caddr_t) &ath);
279 	if (MS(ath, ATH_FF_PROTO) != ATH_FF_PROTO_L2TUNNEL) {
280 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
281 		    ni->ni_macaddr, "fast-frame",
282 		    "unsupport tunnel protocol, header 0x%x", ath);
283 		vap->iv_stats.is_ff_badhdr++;
284 		m_freem(m);
285 		return NULL;
286 	}
287 	/* NB: skip header and alignment padding */
288 	m_adj(m, roundup(sizeof(uint32_t) - 2, 4) + 2);
289 
290 	vap->iv_stats.is_ff_decap++;
291 
292 	/*
293 	 * Decap the first frame, bust it apart from the
294 	 * second and deliver; then decap the second frame
295 	 * and return it to the caller for normal delivery.
296 	 */
297 	m = ieee80211_decap1(m, &framelen);
298 	if (m == NULL) {
299 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
300 		    ni->ni_macaddr, "fast-frame", "%s", "first decap failed");
301 		vap->iv_stats.is_ff_tooshort++;
302 		return NULL;
303 	}
304 	n = m_split(m, framelen, M_NOWAIT);
305 	if (n == NULL) {
306 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
307 		    ni->ni_macaddr, "fast-frame",
308 		    "%s", "unable to split encapsulated frames");
309 		vap->iv_stats.is_ff_split++;
310 		m_freem(m);			/* NB: must reclaim */
311 		return NULL;
312 	}
313 	/* XXX not right for WDS */
314 	vap->iv_deliver_data(vap, ni, m);	/* 1st of pair */
315 
316 	/*
317 	 * Decap second frame.
318 	 */
319 	m_adj(n, roundup2(framelen, 4) - framelen);	/* padding */
320 	n = ieee80211_decap1(n, &framelen);
321 	if (n == NULL) {
322 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
323 		    ni->ni_macaddr, "fast-frame", "%s", "second decap failed");
324 		vap->iv_stats.is_ff_tooshort++;
325 	}
326 	/* XXX verify framelen against mbuf contents */
327 	return n;				/* 2nd delivered by caller */
328 #undef MS
329 #undef FF_LLC_SIZE
330 }
331 
332 /*
333  * Fast frame encapsulation.  There must be two packets
334  * chained with m_nextpkt.  We do header adjustment for
335  * each, add the tunnel encapsulation, and then concatenate
336  * the mbuf chains to form a single frame for transmission.
337  */
338 struct mbuf *
339 ieee80211_ff_encap(struct ieee80211vap *vap, struct mbuf *m1, int hdrspace,
340 	struct ieee80211_key *key)
341 {
342 	struct mbuf *m2;
343 	struct ether_header eh1, eh2;
344 	struct llc *llc;
345 	struct mbuf *m;
346 	int pad;
347 
348 	m2 = m1->m_nextpkt;
349 	if (m2 == NULL) {
350 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
351 		    "%s: only one frame\n", __func__);
352 		goto bad;
353 	}
354 	m1->m_nextpkt = NULL;
355 	/*
356 	 * Include fast frame headers in adjusting header layout.
357 	 */
358 	KASSERT(m1->m_len >= sizeof(eh1), ("no ethernet header!"));
359 	ETHER_HEADER_COPY(&eh1, mtod(m1, caddr_t));
360 	m1 = ieee80211_mbuf_adjust(vap,
361 		hdrspace + sizeof(struct llc) + sizeof(uint32_t) + 2 +
362 		    sizeof(struct ether_header),
363 		key, m1);
364 	if (m1 == NULL) {
365 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
366 		m_freem(m2);
367 		goto bad;
368 	}
369 
370 	/*
371 	 * Copy second frame's Ethernet header out of line
372 	 * and adjust for encapsulation headers.  Note that
373 	 * we make room for padding in case there isn't room
374 	 * at the end of first frame.
375 	 */
376 	KASSERT(m2->m_len >= sizeof(eh2), ("no ethernet header!"));
377 	ETHER_HEADER_COPY(&eh2, mtod(m2, caddr_t));
378 	m2 = ieee80211_mbuf_adjust(vap,
379 		ATH_FF_MAX_HDR_PAD + sizeof(struct ether_header),
380 		NULL, m2);
381 	if (m2 == NULL) {
382 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
383 		goto bad;
384 	}
385 
386 	/*
387 	 * Now do tunnel encapsulation.  First, each
388 	 * frame gets a standard encapsulation.
389 	 */
390 	m1 = ieee80211_ff_encap1(vap, m1, &eh1);
391 	if (m1 == NULL)
392 		goto bad;
393 	m2 = ieee80211_ff_encap1(vap, m2, &eh2);
394 	if (m2 == NULL)
395 		goto bad;
396 
397 	/*
398 	 * Pad leading frame to a 4-byte boundary.  If there
399 	 * is space at the end of the first frame, put it
400 	 * there; otherwise prepend to the front of the second
401 	 * frame.  We know doing the second will always work
402 	 * because we reserve space above.  We prefer appending
403 	 * as this typically has better DMA alignment properties.
404 	 */
405 	for (m = m1; m->m_next != NULL; m = m->m_next)
406 		;
407 	pad = roundup2(m1->m_pkthdr.len, 4) - m1->m_pkthdr.len;
408 	if (pad) {
409 		if (M_TRAILINGSPACE(m) < pad) {		/* prepend to second */
410 			m2->m_data -= pad;
411 			m2->m_len += pad;
412 			m2->m_pkthdr.len += pad;
413 		} else {				/* append to first */
414 			m->m_len += pad;
415 			m1->m_pkthdr.len += pad;
416 		}
417 	}
418 
419 	/*
420 	 * Now, stick 'em together and prepend the tunnel headers;
421 	 * first the Atheros tunnel header (all zero for now) and
422 	 * then a special fast frame LLC.
423 	 *
424 	 * XXX optimize by prepending together
425 	 */
426 	m->m_next = m2;			/* NB: last mbuf from above */
427 	m1->m_pkthdr.len += m2->m_pkthdr.len;
428 	M_PREPEND(m1, sizeof(uint32_t)+2, M_NOWAIT);
429 	if (m1 == NULL) {		/* XXX cannot happen */
430 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
431 		    "%s: no space for tunnel header\n", __func__);
432 		vap->iv_stats.is_tx_nobuf++;
433 		return NULL;
434 	}
435 	memset(mtod(m1, void *), 0, sizeof(uint32_t)+2);
436 
437 	M_PREPEND(m1, sizeof(struct llc), M_NOWAIT);
438 	if (m1 == NULL) {		/* XXX cannot happen */
439 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
440 		    "%s: no space for llc header\n", __func__);
441 		vap->iv_stats.is_tx_nobuf++;
442 		return NULL;
443 	}
444 	llc = mtod(m1, struct llc *);
445 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
446 	llc->llc_control = LLC_UI;
447 	llc->llc_snap.org_code[0] = ATH_FF_SNAP_ORGCODE_0;
448 	llc->llc_snap.org_code[1] = ATH_FF_SNAP_ORGCODE_1;
449 	llc->llc_snap.org_code[2] = ATH_FF_SNAP_ORGCODE_2;
450 	llc->llc_snap.ether_type = htons(ATH_FF_ETH_TYPE);
451 
452 	vap->iv_stats.is_ff_encap++;
453 
454 	return m1;
455 bad:
456 	if (m1 != NULL)
457 		m_freem(m1);
458 	if (m2 != NULL)
459 		m_freem(m2);
460 	return NULL;
461 }
462 
463 static void
464 ff_transmit(struct ieee80211_node *ni, struct mbuf *m)
465 {
466 	struct ieee80211vap *vap = ni->ni_vap;
467 	struct ieee80211com *ic = ni->ni_ic;
468 	int error;
469 
470 	IEEE80211_TX_LOCK_ASSERT(vap->iv_ic);
471 
472 	/* encap and xmit */
473 	m = ieee80211_encap(vap, ni, m);
474 	if (m != NULL) {
475 		struct ifnet *ifp = vap->iv_ifp;
476 
477 		error = ieee80211_parent_xmitpkt(ic, m);;
478 		if (error != 0) {
479 			/* NB: IFQ_HANDOFF reclaims mbuf */
480 			ieee80211_free_node(ni);
481 		} else {
482 			ifp->if_opackets++;
483 		}
484 	} else
485 		ieee80211_free_node(ni);
486 }
487 
488 /*
489  * Flush frames to device; note we re-use the linked list
490  * the frames were stored on and use the sentinel (unchanged)
491  * which may be non-NULL.
492  */
493 static void
494 ff_flush(struct mbuf *head, struct mbuf *last)
495 {
496 	struct mbuf *m, *next;
497 	struct ieee80211_node *ni;
498 	struct ieee80211vap *vap;
499 
500 	for (m = head; m != last; m = next) {
501 		next = m->m_nextpkt;
502 		m->m_nextpkt = NULL;
503 
504 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
505 		vap = ni->ni_vap;
506 
507 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
508 		    "%s: flush frame, age %u", __func__, M_AGE_GET(m));
509 		vap->iv_stats.is_ff_flush++;
510 
511 		ff_transmit(ni, m);
512 	}
513 }
514 
515 /*
516  * Age frames on the staging queue.
517  *
518  * This is called without the comlock held, but it does all its work
519  * behind the comlock.  Because of this, it's possible that the
520  * staging queue will be serviced between the function which called
521  * it and now; thus simply checking that the queue has work in it
522  * may fail.
523  *
524  * See PR kern/174283 for more details.
525  */
526 void
527 ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
528     int quanta)
529 {
530 	struct mbuf *m, *head;
531 	struct ieee80211_node *ni;
532 	struct ieee80211_tx_ampdu *tap;
533 
534 #if 0
535 	KASSERT(sq->head != NULL, ("stageq empty"));
536 #endif
537 
538 	IEEE80211_LOCK(ic);
539 	head = sq->head;
540 	while ((m = sq->head) != NULL && M_AGE_GET(m) < quanta) {
541 		int tid = WME_AC_TO_TID(M_WME_GETAC(m));
542 
543 		/* clear tap ref to frame */
544 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
545 		tap = &ni->ni_tx_ampdu[tid];
546 		KASSERT(tap->txa_private == m, ("staging queue empty"));
547 		tap->txa_private = NULL;
548 
549 		sq->head = m->m_nextpkt;
550 		sq->depth--;
551 	}
552 	if (m == NULL)
553 		sq->tail = NULL;
554 	else
555 		M_AGE_SUB(m, quanta);
556 	IEEE80211_UNLOCK(ic);
557 
558 	IEEE80211_TX_LOCK(ic);
559 	ff_flush(head, m);
560 	IEEE80211_TX_UNLOCK(ic);
561 }
562 
563 static void
564 stageq_add(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *m)
565 {
566 	int age = ieee80211_ffagemax;
567 
568 	IEEE80211_LOCK_ASSERT(ic);
569 
570 	if (sq->tail != NULL) {
571 		sq->tail->m_nextpkt = m;
572 		age -= M_AGE_GET(sq->head);
573 	} else
574 		sq->head = m;
575 	KASSERT(age >= 0, ("age %d", age));
576 	M_AGE_SET(m, age);
577 	m->m_nextpkt = NULL;
578 	sq->tail = m;
579 	sq->depth++;
580 }
581 
582 static void
583 stageq_remove(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *mstaged)
584 {
585 	struct mbuf *m, *mprev;
586 
587 	IEEE80211_LOCK_ASSERT(ic);
588 
589 	mprev = NULL;
590 	for (m = sq->head; m != NULL; m = m->m_nextpkt) {
591 		if (m == mstaged) {
592 			if (mprev == NULL)
593 				sq->head = m->m_nextpkt;
594 			else
595 				mprev->m_nextpkt = m->m_nextpkt;
596 			if (sq->tail == m)
597 				sq->tail = mprev;
598 			sq->depth--;
599 			return;
600 		}
601 		mprev = m;
602 	}
603 	printf("%s: packet not found\n", __func__);
604 }
605 
606 static uint32_t
607 ff_approx_txtime(struct ieee80211_node *ni,
608 	const struct mbuf *m1, const struct mbuf *m2)
609 {
610 	struct ieee80211com *ic = ni->ni_ic;
611 	struct ieee80211vap *vap = ni->ni_vap;
612 	uint32_t framelen;
613 
614 	/*
615 	 * Approximate the frame length to be transmitted. A swag to add
616 	 * the following maximal values to the skb payload:
617 	 *   - 32: 802.11 encap + CRC
618 	 *   - 24: encryption overhead (if wep bit)
619 	 *   - 4 + 6: fast-frame header and padding
620 	 *   - 16: 2 LLC FF tunnel headers
621 	 *   - 14: 1 802.3 FF tunnel header (mbuf already accounts for 2nd)
622 	 */
623 	framelen = m1->m_pkthdr.len + 32 +
624 	    ATH_FF_MAX_HDR_PAD + ATH_FF_MAX_SEP_PAD + ATH_FF_MAX_HDR;
625 	if (vap->iv_flags & IEEE80211_F_PRIVACY)
626 		framelen += 24;
627 	if (m2 != NULL)
628 		framelen += m2->m_pkthdr.len;
629 	return ieee80211_compute_duration(ic->ic_rt, framelen, ni->ni_txrate, 0);
630 }
631 
632 /*
633  * Check if the supplied frame can be partnered with an existing
634  * or pending frame.  Return a reference to any frame that should be
635  * sent on return; otherwise return NULL.
636  */
637 struct mbuf *
638 ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
639 {
640 	struct ieee80211vap *vap = ni->ni_vap;
641 	struct ieee80211com *ic = ni->ni_ic;
642 	struct ieee80211_superg *sg = ic->ic_superg;
643 	const int pri = M_WME_GETAC(m);
644 	struct ieee80211_stageq *sq;
645 	struct ieee80211_tx_ampdu *tap;
646 	struct mbuf *mstaged;
647 	uint32_t txtime, limit;
648 
649 	IEEE80211_TX_UNLOCK_ASSERT(ic);
650 
651 	/*
652 	 * Check if the supplied frame can be aggregated.
653 	 *
654 	 * NB: we allow EAPOL frames to be aggregated with other ucast traffic.
655 	 *     Do 802.1x EAPOL frames proceed in the clear? Then they couldn't
656 	 *     be aggregated with other types of frames when encryption is on?
657 	 */
658 	IEEE80211_LOCK(ic);
659 	tap = &ni->ni_tx_ampdu[WME_AC_TO_TID(pri)];
660 	mstaged = tap->txa_private;		/* NB: we reuse AMPDU state */
661 	ieee80211_txampdu_count_packet(tap);
662 
663 	/*
664 	 * When not in station mode never aggregate a multicast
665 	 * frame; this insures, for example, that a combined frame
666 	 * does not require multiple encryption keys.
667 	 */
668 	if (vap->iv_opmode != IEEE80211_M_STA &&
669 	    ETHER_IS_MULTICAST(mtod(m, struct ether_header *)->ether_dhost)) {
670 		/* XXX flush staged frame? */
671 		IEEE80211_UNLOCK(ic);
672 		return m;
673 	}
674 	/*
675 	 * If there is no frame to combine with and the pps is
676 	 * too low; then do not attempt to aggregate this frame.
677 	 */
678 	if (mstaged == NULL &&
679 	    ieee80211_txampdu_getpps(tap) < ieee80211_ffppsmin) {
680 		IEEE80211_UNLOCK(ic);
681 		return m;
682 	}
683 	sq = &sg->ff_stageq[pri];
684 	/*
685 	 * Check the txop limit to insure the aggregate fits.
686 	 */
687 	limit = IEEE80211_TXOP_TO_US(
688 		ic->ic_wme.wme_chanParams.cap_wmeParams[pri].wmep_txopLimit);
689 	if (limit != 0 &&
690 	    (txtime = ff_approx_txtime(ni, m, mstaged)) > limit) {
691 		/*
692 		 * Aggregate too long, return to the caller for direct
693 		 * transmission.  In addition, flush any pending frame
694 		 * before sending this one.
695 		 */
696 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
697 		    "%s: txtime %u exceeds txop limit %u\n",
698 		    __func__, txtime, limit);
699 
700 		tap->txa_private = NULL;
701 		if (mstaged != NULL)
702 			stageq_remove(ic, sq, mstaged);
703 		IEEE80211_UNLOCK(ic);
704 
705 		if (mstaged != NULL) {
706 			IEEE80211_TX_LOCK(ic);
707 			IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
708 			    "%s: flush staged frame", __func__);
709 			/* encap and xmit */
710 			ff_transmit(ni, mstaged);
711 			IEEE80211_TX_UNLOCK(ic);
712 		}
713 		return m;		/* NB: original frame */
714 	}
715 	/*
716 	 * An aggregation candidate.  If there's a frame to partner
717 	 * with then combine and return for processing.  Otherwise
718 	 * save this frame and wait for a partner to show up (or
719 	 * the frame to be flushed).  Note that staged frames also
720 	 * hold their node reference.
721 	 */
722 	if (mstaged != NULL) {
723 		tap->txa_private = NULL;
724 		stageq_remove(ic, sq, mstaged);
725 		IEEE80211_UNLOCK(ic);
726 
727 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
728 		    "%s: aggregate fast-frame", __func__);
729 		/*
730 		 * Release the node reference; we only need
731 		 * the one already in mstaged.
732 		 */
733 		KASSERT(mstaged->m_pkthdr.rcvif == (void *)ni,
734 		    ("rcvif %p ni %p", mstaged->m_pkthdr.rcvif, ni));
735 		ieee80211_free_node(ni);
736 
737 		m->m_nextpkt = NULL;
738 		mstaged->m_nextpkt = m;
739 		mstaged->m_flags |= M_FF; /* NB: mark for encap work */
740 	} else {
741 		KASSERT(tap->txa_private == NULL,
742 		    ("txa_private %p", tap->txa_private));
743 		tap->txa_private = m;
744 
745 		stageq_add(ic, sq, m);
746 		IEEE80211_UNLOCK(ic);
747 
748 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
749 		    "%s: stage frame, %u queued", __func__, sq->depth);
750 		/* NB: mstaged is NULL */
751 	}
752 	return mstaged;
753 }
754 
755 void
756 ieee80211_ff_node_init(struct ieee80211_node *ni)
757 {
758 	/*
759 	 * Clean FF state on re-associate.  This handles the case
760 	 * where a station leaves w/o notifying us and then returns
761 	 * before node is reaped for inactivity.
762 	 */
763 	ieee80211_ff_node_cleanup(ni);
764 }
765 
766 void
767 ieee80211_ff_node_cleanup(struct ieee80211_node *ni)
768 {
769 	struct ieee80211com *ic = ni->ni_ic;
770 	struct ieee80211_superg *sg = ic->ic_superg;
771 	struct ieee80211_tx_ampdu *tap;
772 	struct mbuf *m, *next_m, *head;
773 	int tid;
774 
775 	IEEE80211_LOCK(ic);
776 	head = NULL;
777 	for (tid = 0; tid < WME_NUM_TID; tid++) {
778 		int ac = TID_TO_WME_AC(tid);
779 
780 		tap = &ni->ni_tx_ampdu[tid];
781 		m = tap->txa_private;
782 		if (m != NULL) {
783 			tap->txa_private = NULL;
784 			stageq_remove(ic, &sg->ff_stageq[ac], m);
785 			m->m_nextpkt = head;
786 			head = m;
787 		}
788 	}
789 	IEEE80211_UNLOCK(ic);
790 
791 	/*
792 	 * Free mbufs, taking care to not dereference the mbuf after
793 	 * we free it (hence grabbing m_nextpkt before we free it.)
794 	 */
795 	m = head;
796 	while (m != NULL) {
797 		next_m = m->m_nextpkt;
798 		m_freem(m);
799 		ieee80211_free_node(ni);
800 		m = next_m;
801 	}
802 }
803 
804 /*
805  * Switch between turbo and non-turbo operating modes.
806  * Use the specified channel flags to locate the new
807  * channel, update 802.11 state, and then call back into
808  * the driver to effect the change.
809  */
810 void
811 ieee80211_dturbo_switch(struct ieee80211vap *vap, int newflags)
812 {
813 	struct ieee80211com *ic = vap->iv_ic;
814 	struct ieee80211_channel *chan;
815 
816 	chan = ieee80211_find_channel(ic, ic->ic_bsschan->ic_freq, newflags);
817 	if (chan == NULL) {		/* XXX should not happen */
818 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
819 		    "%s: no channel with freq %u flags 0x%x\n",
820 		    __func__, ic->ic_bsschan->ic_freq, newflags);
821 		return;
822 	}
823 
824 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
825 	    "%s: %s -> %s (freq %u flags 0x%x)\n", __func__,
826 	    ieee80211_phymode_name[ieee80211_chan2mode(ic->ic_bsschan)],
827 	    ieee80211_phymode_name[ieee80211_chan2mode(chan)],
828 	    chan->ic_freq, chan->ic_flags);
829 
830 	ic->ic_bsschan = chan;
831 	ic->ic_prevchan = ic->ic_curchan;
832 	ic->ic_curchan = chan;
833 	ic->ic_rt = ieee80211_get_ratetable(chan);
834 	ic->ic_set_channel(ic);
835 	ieee80211_radiotap_chan_change(ic);
836 	/* NB: do not need to reset ERP state 'cuz we're in sta mode */
837 }
838 
839 /*
840  * Return the current ``state'' of an Atheros capbility.
841  * If associated in station mode report the negotiated
842  * setting. Otherwise report the current setting.
843  */
844 static int
845 getathcap(struct ieee80211vap *vap, int cap)
846 {
847 	if (vap->iv_opmode == IEEE80211_M_STA &&
848 	    vap->iv_state == IEEE80211_S_RUN)
849 		return IEEE80211_ATH_CAP(vap, vap->iv_bss, cap) != 0;
850 	else
851 		return (vap->iv_flags & cap) != 0;
852 }
853 
854 static int
855 superg_ioctl_get80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
856 {
857 	switch (ireq->i_type) {
858 	case IEEE80211_IOC_FF:
859 		ireq->i_val = getathcap(vap, IEEE80211_F_FF);
860 		break;
861 	case IEEE80211_IOC_TURBOP:
862 		ireq->i_val = getathcap(vap, IEEE80211_F_TURBOP);
863 		break;
864 	default:
865 		return ENOSYS;
866 	}
867 	return 0;
868 }
869 IEEE80211_IOCTL_GET(superg, superg_ioctl_get80211);
870 
871 static int
872 superg_ioctl_set80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
873 {
874 	switch (ireq->i_type) {
875 	case IEEE80211_IOC_FF:
876 		if (ireq->i_val) {
877 			if ((vap->iv_caps & IEEE80211_C_FF) == 0)
878 				return EOPNOTSUPP;
879 			vap->iv_flags |= IEEE80211_F_FF;
880 		} else
881 			vap->iv_flags &= ~IEEE80211_F_FF;
882 		return ENETRESET;
883 	case IEEE80211_IOC_TURBOP:
884 		if (ireq->i_val) {
885 			if ((vap->iv_caps & IEEE80211_C_TURBOP) == 0)
886 				return EOPNOTSUPP;
887 			vap->iv_flags |= IEEE80211_F_TURBOP;
888 		} else
889 			vap->iv_flags &= ~IEEE80211_F_TURBOP;
890 		return ENETRESET;
891 	default:
892 		return ENOSYS;
893 	}
894 	return 0;
895 }
896 IEEE80211_IOCTL_SET(superg, superg_ioctl_set80211);
897 
898 #endif	/* IEEE80211_SUPPORT_SUPERG */
899