xref: /freebsd/sys/net80211/ieee80211_superg.c (revision 325151a3)
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/if.h>
42 #include <net/if_var.h>
43 #include <net/if_llc.h>
44 #include <net/if_media.h>
45 #include <net/bpf.h>
46 #include <net/ethernet.h>
47 
48 #include <net80211/ieee80211_var.h>
49 #include <net80211/ieee80211_input.h>
50 #include <net80211/ieee80211_phy.h>
51 #include <net80211/ieee80211_superg.h>
52 
53 /*
54  * Atheros fast-frame encapsulation format.
55  * FF max payload:
56  * 802.2 + FFHDR + HPAD + 802.3 + 802.2 + 1500 + SPAD + 802.3 + 802.2 + 1500:
57  *   8   +   4   +  4   +   14  +   8   + 1500 +  6   +   14  +   8   + 1500
58  * = 3066
59  */
60 /* fast frame header is 32-bits */
61 #define	ATH_FF_PROTO	0x0000003f	/* protocol */
62 #define	ATH_FF_PROTO_S	0
63 #define	ATH_FF_FTYPE	0x000000c0	/* frame type */
64 #define	ATH_FF_FTYPE_S	6
65 #define	ATH_FF_HLEN32	0x00000300	/* optional hdr length */
66 #define	ATH_FF_HLEN32_S	8
67 #define	ATH_FF_SEQNUM	0x001ffc00	/* sequence number */
68 #define	ATH_FF_SEQNUM_S	10
69 #define	ATH_FF_OFFSET	0xffe00000	/* offset to 2nd payload */
70 #define	ATH_FF_OFFSET_S	21
71 
72 #define	ATH_FF_MAX_HDR_PAD	4
73 #define	ATH_FF_MAX_SEP_PAD	6
74 #define	ATH_FF_MAX_HDR		30
75 
76 #define	ATH_FF_PROTO_L2TUNNEL	0	/* L2 tunnel protocol */
77 #define	ATH_FF_ETH_TYPE		0x88bd	/* Ether type for encapsulated frames */
78 #define	ATH_FF_SNAP_ORGCODE_0	0x00
79 #define	ATH_FF_SNAP_ORGCODE_1	0x03
80 #define	ATH_FF_SNAP_ORGCODE_2	0x7f
81 
82 #define	ATH_FF_TXQMIN	2		/* min txq depth for staging */
83 #define	ATH_FF_TXQMAX	50		/* maximum # of queued frames allowed */
84 #define	ATH_FF_STAGEMAX	5		/* max waiting period for staged frame*/
85 
86 #define	ETHER_HEADER_COPY(dst, src) \
87 	memcpy(dst, src, sizeof(struct ether_header))
88 
89 static	int ieee80211_ffppsmin = 2;	/* pps threshold for ff aggregation */
90 SYSCTL_INT(_net_wlan, OID_AUTO, ffppsmin, CTLFLAG_RW,
91 	&ieee80211_ffppsmin, 0, "min packet rate before fast-frame staging");
92 static	int ieee80211_ffagemax = -1;	/* max time frames held on stage q */
93 SYSCTL_PROC(_net_wlan, OID_AUTO, ffagemax, CTLTYPE_INT | CTLFLAG_RW,
94 	&ieee80211_ffagemax, 0, ieee80211_sysctl_msecs_ticks, "I",
95 	"max hold time for fast-frame staging (ms)");
96 
97 void
98 ieee80211_superg_attach(struct ieee80211com *ic)
99 {
100 	struct ieee80211_superg *sg;
101 
102 	if (ic->ic_caps & IEEE80211_C_FF) {
103 		sg = (struct ieee80211_superg *) IEEE80211_MALLOC(
104 		     sizeof(struct ieee80211_superg), M_80211_VAP,
105 		     IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
106 		if (sg == NULL) {
107 			printf("%s: cannot allocate SuperG state block\n",
108 			    __func__);
109 			return;
110 		}
111 		ic->ic_superg = sg;
112 	}
113 	ieee80211_ffagemax = msecs_to_ticks(150);
114 }
115 
116 void
117 ieee80211_superg_detach(struct ieee80211com *ic)
118 {
119 	if (ic->ic_superg != NULL) {
120 		IEEE80211_FREE(ic->ic_superg, M_80211_VAP);
121 		ic->ic_superg = NULL;
122 	}
123 }
124 
125 void
126 ieee80211_superg_vattach(struct ieee80211vap *vap)
127 {
128 	struct ieee80211com *ic = vap->iv_ic;
129 
130 	if (ic->ic_superg == NULL)	/* NB: can't do fast-frames w/o state */
131 		vap->iv_caps &= ~IEEE80211_C_FF;
132 	if (vap->iv_caps & IEEE80211_C_FF)
133 		vap->iv_flags |= IEEE80211_F_FF;
134 	/* NB: we only implement sta mode */
135 	if (vap->iv_opmode == IEEE80211_M_STA &&
136 	    (vap->iv_caps & IEEE80211_C_TURBOP))
137 		vap->iv_flags |= IEEE80211_F_TURBOP;
138 }
139 
140 void
141 ieee80211_superg_vdetach(struct ieee80211vap *vap)
142 {
143 }
144 
145 #define	ATH_OUI_BYTES		0x00, 0x03, 0x7f
146 /*
147  * Add a WME information element to a frame.
148  */
149 uint8_t *
150 ieee80211_add_ath(uint8_t *frm, uint8_t caps, ieee80211_keyix defkeyix)
151 {
152 	static const struct ieee80211_ath_ie info = {
153 		.ath_id		= IEEE80211_ELEMID_VENDOR,
154 		.ath_len	= sizeof(struct ieee80211_ath_ie) - 2,
155 		.ath_oui	= { ATH_OUI_BYTES },
156 		.ath_oui_type	= ATH_OUI_TYPE,
157 		.ath_oui_subtype= ATH_OUI_SUBTYPE,
158 		.ath_version	= ATH_OUI_VERSION,
159 	};
160 	struct ieee80211_ath_ie *ath = (struct ieee80211_ath_ie *) frm;
161 
162 	memcpy(frm, &info, sizeof(info));
163 	ath->ath_capability = caps;
164 	if (defkeyix != IEEE80211_KEYIX_NONE) {
165 		ath->ath_defkeyix[0] = (defkeyix & 0xff);
166 		ath->ath_defkeyix[1] = ((defkeyix >> 8) & 0xff);
167 	} else {
168 		ath->ath_defkeyix[0] = 0xff;
169 		ath->ath_defkeyix[1] = 0x7f;
170 	}
171 	return frm + sizeof(info);
172 }
173 #undef ATH_OUI_BYTES
174 
175 uint8_t *
176 ieee80211_add_athcaps(uint8_t *frm, const struct ieee80211_node *bss)
177 {
178 	const struct ieee80211vap *vap = bss->ni_vap;
179 
180 	return ieee80211_add_ath(frm,
181 	    vap->iv_flags & IEEE80211_F_ATHEROS,
182 	    ((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
183 	    bss->ni_authmode != IEEE80211_AUTH_8021X) ?
184 	    vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
185 }
186 
187 void
188 ieee80211_parse_ath(struct ieee80211_node *ni, uint8_t *ie)
189 {
190 	const struct ieee80211_ath_ie *ath =
191 		(const struct ieee80211_ath_ie *) ie;
192 
193 	ni->ni_ath_flags = ath->ath_capability;
194 	ni->ni_ath_defkeyix = LE_READ_2(&ath->ath_defkeyix);
195 }
196 
197 int
198 ieee80211_parse_athparams(struct ieee80211_node *ni, uint8_t *frm,
199 	const struct ieee80211_frame *wh)
200 {
201 	struct ieee80211vap *vap = ni->ni_vap;
202 	const struct ieee80211_ath_ie *ath;
203 	u_int len = frm[1];
204 	int capschanged;
205 	uint16_t defkeyix;
206 
207 	if (len < sizeof(struct ieee80211_ath_ie)-2) {
208 		IEEE80211_DISCARD_IE(vap,
209 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_SUPERG,
210 		    wh, "Atheros", "too short, len %u", len);
211 		return -1;
212 	}
213 	ath = (const struct ieee80211_ath_ie *)frm;
214 	capschanged = (ni->ni_ath_flags != ath->ath_capability);
215 	defkeyix = LE_READ_2(ath->ath_defkeyix);
216 	if (capschanged || defkeyix != ni->ni_ath_defkeyix) {
217 		ni->ni_ath_flags = ath->ath_capability;
218 		ni->ni_ath_defkeyix = defkeyix;
219 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
220 		    "ath ie change: new caps 0x%x defkeyix 0x%x",
221 		    ni->ni_ath_flags, ni->ni_ath_defkeyix);
222 	}
223 	if (IEEE80211_ATH_CAP(vap, ni, ATHEROS_CAP_TURBO_PRIME)) {
224 		uint16_t curflags, newflags;
225 
226 		/*
227 		 * Check for turbo mode switch.  Calculate flags
228 		 * for the new mode and effect the switch.
229 		 */
230 		newflags = curflags = vap->iv_ic->ic_bsschan->ic_flags;
231 		/* NB: BOOST is not in ic_flags, so get it from the ie */
232 		if (ath->ath_capability & ATHEROS_CAP_BOOST)
233 			newflags |= IEEE80211_CHAN_TURBO;
234 		else
235 			newflags &= ~IEEE80211_CHAN_TURBO;
236 		if (newflags != curflags)
237 			ieee80211_dturbo_switch(vap, newflags);
238 	}
239 	return capschanged;
240 }
241 
242 /*
243  * Decap the encapsulated frame pair and dispatch the first
244  * for delivery.  The second frame is returned for delivery
245  * via the normal path.
246  */
247 struct mbuf *
248 ieee80211_ff_decap(struct ieee80211_node *ni, struct mbuf *m)
249 {
250 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
251 #define	MS(x,f)	(((x) & f) >> f##_S)
252 	struct ieee80211vap *vap = ni->ni_vap;
253 	struct llc *llc;
254 	uint32_t ath;
255 	struct mbuf *n;
256 	int framelen;
257 
258 	/* NB: we assume caller does this check for us */
259 	KASSERT(IEEE80211_ATH_CAP(vap, ni, IEEE80211_NODE_FF),
260 	    ("ff not negotiated"));
261 	/*
262 	 * Check for fast-frame tunnel encapsulation.
263 	 */
264 	if (m->m_pkthdr.len < 3*FF_LLC_SIZE)
265 		return m;
266 	if (m->m_len < FF_LLC_SIZE &&
267 	    (m = m_pullup(m, FF_LLC_SIZE)) == NULL) {
268 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
269 		    ni->ni_macaddr, "fast-frame",
270 		    "%s", "m_pullup(llc) failed");
271 		vap->iv_stats.is_rx_tooshort++;
272 		return NULL;
273 	}
274 	llc = (struct llc *)(mtod(m, uint8_t *) +
275 	    sizeof(struct ether_header));
276 	if (llc->llc_snap.ether_type != htons(ATH_FF_ETH_TYPE))
277 		return m;
278 	m_adj(m, FF_LLC_SIZE);
279 	m_copydata(m, 0, sizeof(uint32_t), (caddr_t) &ath);
280 	if (MS(ath, ATH_FF_PROTO) != ATH_FF_PROTO_L2TUNNEL) {
281 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
282 		    ni->ni_macaddr, "fast-frame",
283 		    "unsupport tunnel protocol, header 0x%x", ath);
284 		vap->iv_stats.is_ff_badhdr++;
285 		m_freem(m);
286 		return NULL;
287 	}
288 	/* NB: skip header and alignment padding */
289 	m_adj(m, roundup(sizeof(uint32_t) - 2, 4) + 2);
290 
291 	vap->iv_stats.is_ff_decap++;
292 
293 	/*
294 	 * Decap the first frame, bust it apart from the
295 	 * second and deliver; then decap the second frame
296 	 * and return it to the caller for normal delivery.
297 	 */
298 	m = ieee80211_decap1(m, &framelen);
299 	if (m == NULL) {
300 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
301 		    ni->ni_macaddr, "fast-frame", "%s", "first decap failed");
302 		vap->iv_stats.is_ff_tooshort++;
303 		return NULL;
304 	}
305 	n = m_split(m, framelen, M_NOWAIT);
306 	if (n == NULL) {
307 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
308 		    ni->ni_macaddr, "fast-frame",
309 		    "%s", "unable to split encapsulated frames");
310 		vap->iv_stats.is_ff_split++;
311 		m_freem(m);			/* NB: must reclaim */
312 		return NULL;
313 	}
314 	/* XXX not right for WDS */
315 	vap->iv_deliver_data(vap, ni, m);	/* 1st of pair */
316 
317 	/*
318 	 * Decap second frame.
319 	 */
320 	m_adj(n, roundup2(framelen, 4) - framelen);	/* padding */
321 	n = ieee80211_decap1(n, &framelen);
322 	if (n == NULL) {
323 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
324 		    ni->ni_macaddr, "fast-frame", "%s", "second decap failed");
325 		vap->iv_stats.is_ff_tooshort++;
326 	}
327 	/* XXX verify framelen against mbuf contents */
328 	return n;				/* 2nd delivered by caller */
329 #undef MS
330 #undef FF_LLC_SIZE
331 }
332 
333 /*
334  * Fast frame encapsulation.  There must be two packets
335  * chained with m_nextpkt.  We do header adjustment for
336  * each, add the tunnel encapsulation, and then concatenate
337  * the mbuf chains to form a single frame for transmission.
338  */
339 struct mbuf *
340 ieee80211_ff_encap(struct ieee80211vap *vap, struct mbuf *m1, int hdrspace,
341 	struct ieee80211_key *key)
342 {
343 	struct mbuf *m2;
344 	struct ether_header eh1, eh2;
345 	struct llc *llc;
346 	struct mbuf *m;
347 	int pad;
348 
349 	m2 = m1->m_nextpkt;
350 	if (m2 == NULL) {
351 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
352 		    "%s: only one frame\n", __func__);
353 		goto bad;
354 	}
355 	m1->m_nextpkt = NULL;
356 	/*
357 	 * Include fast frame headers in adjusting header layout.
358 	 */
359 	KASSERT(m1->m_len >= sizeof(eh1), ("no ethernet header!"));
360 	ETHER_HEADER_COPY(&eh1, mtod(m1, caddr_t));
361 	m1 = ieee80211_mbuf_adjust(vap,
362 		hdrspace + sizeof(struct llc) + sizeof(uint32_t) + 2 +
363 		    sizeof(struct ether_header),
364 		key, m1);
365 	if (m1 == NULL) {
366 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
367 		m_freem(m2);
368 		goto bad;
369 	}
370 
371 	/*
372 	 * Copy second frame's Ethernet header out of line
373 	 * and adjust for encapsulation headers.  Note that
374 	 * we make room for padding in case there isn't room
375 	 * at the end of first frame.
376 	 */
377 	KASSERT(m2->m_len >= sizeof(eh2), ("no ethernet header!"));
378 	ETHER_HEADER_COPY(&eh2, mtod(m2, caddr_t));
379 	m2 = ieee80211_mbuf_adjust(vap,
380 		ATH_FF_MAX_HDR_PAD + sizeof(struct ether_header),
381 		NULL, m2);
382 	if (m2 == NULL) {
383 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
384 		goto bad;
385 	}
386 
387 	/*
388 	 * Now do tunnel encapsulation.  First, each
389 	 * frame gets a standard encapsulation.
390 	 */
391 	m1 = ieee80211_ff_encap1(vap, m1, &eh1);
392 	if (m1 == NULL)
393 		goto bad;
394 	m2 = ieee80211_ff_encap1(vap, m2, &eh2);
395 	if (m2 == NULL)
396 		goto bad;
397 
398 	/*
399 	 * Pad leading frame to a 4-byte boundary.  If there
400 	 * is space at the end of the first frame, put it
401 	 * there; otherwise prepend to the front of the second
402 	 * frame.  We know doing the second will always work
403 	 * because we reserve space above.  We prefer appending
404 	 * as this typically has better DMA alignment properties.
405 	 */
406 	for (m = m1; m->m_next != NULL; m = m->m_next)
407 		;
408 	pad = roundup2(m1->m_pkthdr.len, 4) - m1->m_pkthdr.len;
409 	if (pad) {
410 		if (M_TRAILINGSPACE(m) < pad) {		/* prepend to second */
411 			m2->m_data -= pad;
412 			m2->m_len += pad;
413 			m2->m_pkthdr.len += pad;
414 		} else {				/* append to first */
415 			m->m_len += pad;
416 			m1->m_pkthdr.len += pad;
417 		}
418 	}
419 
420 	/*
421 	 * Now, stick 'em together and prepend the tunnel headers;
422 	 * first the Atheros tunnel header (all zero for now) and
423 	 * then a special fast frame LLC.
424 	 *
425 	 * XXX optimize by prepending together
426 	 */
427 	m->m_next = m2;			/* NB: last mbuf from above */
428 	m1->m_pkthdr.len += m2->m_pkthdr.len;
429 	M_PREPEND(m1, sizeof(uint32_t)+2, M_NOWAIT);
430 	if (m1 == NULL) {		/* XXX cannot happen */
431 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
432 		    "%s: no space for tunnel header\n", __func__);
433 		vap->iv_stats.is_tx_nobuf++;
434 		return NULL;
435 	}
436 	memset(mtod(m1, void *), 0, sizeof(uint32_t)+2);
437 
438 	M_PREPEND(m1, sizeof(struct llc), M_NOWAIT);
439 	if (m1 == NULL) {		/* XXX cannot happen */
440 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
441 		    "%s: no space for llc header\n", __func__);
442 		vap->iv_stats.is_tx_nobuf++;
443 		return NULL;
444 	}
445 	llc = mtod(m1, struct llc *);
446 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
447 	llc->llc_control = LLC_UI;
448 	llc->llc_snap.org_code[0] = ATH_FF_SNAP_ORGCODE_0;
449 	llc->llc_snap.org_code[1] = ATH_FF_SNAP_ORGCODE_1;
450 	llc->llc_snap.org_code[2] = ATH_FF_SNAP_ORGCODE_2;
451 	llc->llc_snap.ether_type = htons(ATH_FF_ETH_TYPE);
452 
453 	vap->iv_stats.is_ff_encap++;
454 
455 	return m1;
456 bad:
457 	if (m1 != NULL)
458 		m_freem(m1);
459 	if (m2 != NULL)
460 		m_freem(m2);
461 	return NULL;
462 }
463 
464 static void
465 ff_transmit(struct ieee80211_node *ni, struct mbuf *m)
466 {
467 	struct ieee80211vap *vap = ni->ni_vap;
468 	struct ieee80211com *ic = ni->ni_ic;
469 	int error;
470 
471 	IEEE80211_TX_LOCK_ASSERT(vap->iv_ic);
472 
473 	/* encap and xmit */
474 	m = ieee80211_encap(vap, ni, m);
475 	if (m != NULL) {
476 		struct ifnet *ifp = vap->iv_ifp;
477 
478 		error = ieee80211_parent_xmitpkt(ic, m);
479 		if (!error)
480 			if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
481 	} else
482 		ieee80211_free_node(ni);
483 }
484 
485 /*
486  * Flush frames to device; note we re-use the linked list
487  * the frames were stored on and use the sentinel (unchanged)
488  * which may be non-NULL.
489  */
490 static void
491 ff_flush(struct mbuf *head, struct mbuf *last)
492 {
493 	struct mbuf *m, *next;
494 	struct ieee80211_node *ni;
495 	struct ieee80211vap *vap;
496 
497 	for (m = head; m != last; m = next) {
498 		next = m->m_nextpkt;
499 		m->m_nextpkt = NULL;
500 
501 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
502 		vap = ni->ni_vap;
503 
504 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
505 		    "%s: flush frame, age %u", __func__, M_AGE_GET(m));
506 		vap->iv_stats.is_ff_flush++;
507 
508 		ff_transmit(ni, m);
509 	}
510 }
511 
512 /*
513  * Age frames on the staging queue.
514  *
515  * This is called without the comlock held, but it does all its work
516  * behind the comlock.  Because of this, it's possible that the
517  * staging queue will be serviced between the function which called
518  * it and now; thus simply checking that the queue has work in it
519  * may fail.
520  *
521  * See PR kern/174283 for more details.
522  */
523 void
524 ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
525     int quanta)
526 {
527 	struct mbuf *m, *head;
528 	struct ieee80211_node *ni;
529 
530 #if 0
531 	KASSERT(sq->head != NULL, ("stageq empty"));
532 #endif
533 
534 	IEEE80211_LOCK(ic);
535 	head = sq->head;
536 	while ((m = sq->head) != NULL && M_AGE_GET(m) < quanta) {
537 		int tid = WME_AC_TO_TID(M_WME_GETAC(m));
538 
539 		/* clear staging ref to frame */
540 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
541 		KASSERT(ni->ni_tx_superg[tid] == m, ("staging queue empty"));
542 		ni->ni_tx_superg[tid] = NULL;
543 
544 		sq->head = m->m_nextpkt;
545 		sq->depth--;
546 	}
547 	if (m == NULL)
548 		sq->tail = NULL;
549 	else
550 		M_AGE_SUB(m, quanta);
551 	IEEE80211_UNLOCK(ic);
552 
553 	IEEE80211_TX_LOCK(ic);
554 	ff_flush(head, m);
555 	IEEE80211_TX_UNLOCK(ic);
556 }
557 
558 static void
559 stageq_add(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *m)
560 {
561 	int age = ieee80211_ffagemax;
562 
563 	IEEE80211_LOCK_ASSERT(ic);
564 
565 	if (sq->tail != NULL) {
566 		sq->tail->m_nextpkt = m;
567 		age -= M_AGE_GET(sq->head);
568 	} else
569 		sq->head = m;
570 	KASSERT(age >= 0, ("age %d", age));
571 	M_AGE_SET(m, age);
572 	m->m_nextpkt = NULL;
573 	sq->tail = m;
574 	sq->depth++;
575 }
576 
577 static void
578 stageq_remove(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *mstaged)
579 {
580 	struct mbuf *m, *mprev;
581 
582 	IEEE80211_LOCK_ASSERT(ic);
583 
584 	mprev = NULL;
585 	for (m = sq->head; m != NULL; m = m->m_nextpkt) {
586 		if (m == mstaged) {
587 			if (mprev == NULL)
588 				sq->head = m->m_nextpkt;
589 			else
590 				mprev->m_nextpkt = m->m_nextpkt;
591 			if (sq->tail == m)
592 				sq->tail = mprev;
593 			sq->depth--;
594 			return;
595 		}
596 		mprev = m;
597 	}
598 	printf("%s: packet not found\n", __func__);
599 }
600 
601 static uint32_t
602 ff_approx_txtime(struct ieee80211_node *ni,
603 	const struct mbuf *m1, const struct mbuf *m2)
604 {
605 	struct ieee80211com *ic = ni->ni_ic;
606 	struct ieee80211vap *vap = ni->ni_vap;
607 	uint32_t framelen;
608 
609 	/*
610 	 * Approximate the frame length to be transmitted. A swag to add
611 	 * the following maximal values to the skb payload:
612 	 *   - 32: 802.11 encap + CRC
613 	 *   - 24: encryption overhead (if wep bit)
614 	 *   - 4 + 6: fast-frame header and padding
615 	 *   - 16: 2 LLC FF tunnel headers
616 	 *   - 14: 1 802.3 FF tunnel header (mbuf already accounts for 2nd)
617 	 */
618 	framelen = m1->m_pkthdr.len + 32 +
619 	    ATH_FF_MAX_HDR_PAD + ATH_FF_MAX_SEP_PAD + ATH_FF_MAX_HDR;
620 	if (vap->iv_flags & IEEE80211_F_PRIVACY)
621 		framelen += 24;
622 	if (m2 != NULL)
623 		framelen += m2->m_pkthdr.len;
624 	return ieee80211_compute_duration(ic->ic_rt, framelen, ni->ni_txrate, 0);
625 }
626 
627 /*
628  * Check if the supplied frame can be partnered with an existing
629  * or pending frame.  Return a reference to any frame that should be
630  * sent on return; otherwise return NULL.
631  */
632 struct mbuf *
633 ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
634 {
635 	struct ieee80211vap *vap = ni->ni_vap;
636 	struct ieee80211com *ic = ni->ni_ic;
637 	struct ieee80211_superg *sg = ic->ic_superg;
638 	const int pri = M_WME_GETAC(m);
639 	struct ieee80211_stageq *sq;
640 	struct ieee80211_tx_ampdu *tap;
641 	struct mbuf *mstaged;
642 	uint32_t txtime, limit;
643 
644 	IEEE80211_TX_UNLOCK_ASSERT(ic);
645 
646 	/*
647 	 * Check if the supplied frame can be aggregated.
648 	 *
649 	 * NB: we allow EAPOL frames to be aggregated with other ucast traffic.
650 	 *     Do 802.1x EAPOL frames proceed in the clear? Then they couldn't
651 	 *     be aggregated with other types of frames when encryption is on?
652 	 */
653 	IEEE80211_LOCK(ic);
654 	tap = &ni->ni_tx_ampdu[WME_AC_TO_TID(pri)];
655 	mstaged = ni->ni_tx_superg[WME_AC_TO_TID(pri)];
656 	/* XXX NOTE: reusing packet counter state from A-MPDU */
657 	/*
658 	 * XXX NOTE: this means we're double-counting; it should just
659 	 * be done in ieee80211_output.c once for both superg and A-MPDU.
660 	 */
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 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = 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 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = 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(ni->ni_tx_superg[WME_AC_TO_TID(pri)]== NULL,
742 		    ("ni_tx_superg[]: %p",
743 		    ni->ni_tx_superg[WME_AC_TO_TID(pri)]));
744 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = m;
745 
746 		stageq_add(ic, sq, m);
747 		IEEE80211_UNLOCK(ic);
748 
749 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
750 		    "%s: stage frame, %u queued", __func__, sq->depth);
751 		/* NB: mstaged is NULL */
752 	}
753 	return mstaged;
754 }
755 
756 void
757 ieee80211_ff_node_init(struct ieee80211_node *ni)
758 {
759 	/*
760 	 * Clean FF state on re-associate.  This handles the case
761 	 * where a station leaves w/o notifying us and then returns
762 	 * before node is reaped for inactivity.
763 	 */
764 	ieee80211_ff_node_cleanup(ni);
765 }
766 
767 void
768 ieee80211_ff_node_cleanup(struct ieee80211_node *ni)
769 {
770 	struct ieee80211com *ic = ni->ni_ic;
771 	struct ieee80211_superg *sg = ic->ic_superg;
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 		 * XXX Initialise the packet counter.
781 		 *
782 		 * This may be double-work for 11n stations;
783 		 * but without it we never setup things.
784 		 */
785 		ieee80211_txampdu_init_pps(&ni->ni_tx_ampdu[tid]);
786 		m = ni->ni_tx_superg[tid];
787 		if (m != NULL) {
788 			ni->ni_tx_superg[tid] = NULL;
789 			stageq_remove(ic, &sg->ff_stageq[ac], m);
790 			m->m_nextpkt = head;
791 			head = m;
792 		}
793 	}
794 	IEEE80211_UNLOCK(ic);
795 
796 	/*
797 	 * Free mbufs, taking care to not dereference the mbuf after
798 	 * we free it (hence grabbing m_nextpkt before we free it.)
799 	 */
800 	m = head;
801 	while (m != NULL) {
802 		next_m = m->m_nextpkt;
803 		m_freem(m);
804 		ieee80211_free_node(ni);
805 		m = next_m;
806 	}
807 }
808 
809 /*
810  * Switch between turbo and non-turbo operating modes.
811  * Use the specified channel flags to locate the new
812  * channel, update 802.11 state, and then call back into
813  * the driver to effect the change.
814  */
815 void
816 ieee80211_dturbo_switch(struct ieee80211vap *vap, int newflags)
817 {
818 	struct ieee80211com *ic = vap->iv_ic;
819 	struct ieee80211_channel *chan;
820 
821 	chan = ieee80211_find_channel(ic, ic->ic_bsschan->ic_freq, newflags);
822 	if (chan == NULL) {		/* XXX should not happen */
823 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
824 		    "%s: no channel with freq %u flags 0x%x\n",
825 		    __func__, ic->ic_bsschan->ic_freq, newflags);
826 		return;
827 	}
828 
829 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
830 	    "%s: %s -> %s (freq %u flags 0x%x)\n", __func__,
831 	    ieee80211_phymode_name[ieee80211_chan2mode(ic->ic_bsschan)],
832 	    ieee80211_phymode_name[ieee80211_chan2mode(chan)],
833 	    chan->ic_freq, chan->ic_flags);
834 
835 	ic->ic_bsschan = chan;
836 	ic->ic_prevchan = ic->ic_curchan;
837 	ic->ic_curchan = chan;
838 	ic->ic_rt = ieee80211_get_ratetable(chan);
839 	ic->ic_set_channel(ic);
840 	ieee80211_radiotap_chan_change(ic);
841 	/* NB: do not need to reset ERP state 'cuz we're in sta mode */
842 }
843 
844 /*
845  * Return the current ``state'' of an Atheros capbility.
846  * If associated in station mode report the negotiated
847  * setting. Otherwise report the current setting.
848  */
849 static int
850 getathcap(struct ieee80211vap *vap, int cap)
851 {
852 	if (vap->iv_opmode == IEEE80211_M_STA &&
853 	    vap->iv_state == IEEE80211_S_RUN)
854 		return IEEE80211_ATH_CAP(vap, vap->iv_bss, cap) != 0;
855 	else
856 		return (vap->iv_flags & cap) != 0;
857 }
858 
859 static int
860 superg_ioctl_get80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
861 {
862 	switch (ireq->i_type) {
863 	case IEEE80211_IOC_FF:
864 		ireq->i_val = getathcap(vap, IEEE80211_F_FF);
865 		break;
866 	case IEEE80211_IOC_TURBOP:
867 		ireq->i_val = getathcap(vap, IEEE80211_F_TURBOP);
868 		break;
869 	default:
870 		return ENOSYS;
871 	}
872 	return 0;
873 }
874 IEEE80211_IOCTL_GET(superg, superg_ioctl_get80211);
875 
876 static int
877 superg_ioctl_set80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
878 {
879 	switch (ireq->i_type) {
880 	case IEEE80211_IOC_FF:
881 		if (ireq->i_val) {
882 			if ((vap->iv_caps & IEEE80211_C_FF) == 0)
883 				return EOPNOTSUPP;
884 			vap->iv_flags |= IEEE80211_F_FF;
885 		} else
886 			vap->iv_flags &= ~IEEE80211_F_FF;
887 		return ENETRESET;
888 	case IEEE80211_IOC_TURBOP:
889 		if (ireq->i_val) {
890 			if ((vap->iv_caps & IEEE80211_C_TURBOP) == 0)
891 				return EOPNOTSUPP;
892 			vap->iv_flags |= IEEE80211_F_TURBOP;
893 		} else
894 			vap->iv_flags &= ~IEEE80211_F_TURBOP;
895 		return ENETRESET;
896 	default:
897 		return ENOSYS;
898 	}
899 	return 0;
900 }
901 IEEE80211_IOCTL_SET(superg, superg_ioctl_set80211);
902 
903 #endif	/* IEEE80211_SUPPORT_SUPERG */
904