xref: /freebsd/sys/net80211/ieee80211_superg.c (revision 3fc36ee018bb836bd1796067cf4ef8683f166ebc)
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 	IEEE80211_FF_LOCK_INIT(ic, ic->ic_name);
103 
104 	sg = (struct ieee80211_superg *) IEEE80211_MALLOC(
105 	     sizeof(struct ieee80211_superg), M_80211_VAP,
106 	     IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
107 	if (sg == NULL) {
108 		printf("%s: cannot allocate SuperG state block\n",
109 		    __func__);
110 		return;
111 	}
112 	ic->ic_superg = sg;
113 
114 	/*
115 	 * Default to not being so aggressive for FF/AMSDU
116 	 * aging, otherwise we may hold a frame around
117 	 * for way too long before we expire it out.
118 	 */
119 	ieee80211_ffagemax = msecs_to_ticks(2);
120 }
121 
122 void
123 ieee80211_superg_detach(struct ieee80211com *ic)
124 {
125 	IEEE80211_FF_LOCK_DESTROY(ic);
126 
127 	if (ic->ic_superg != NULL) {
128 		IEEE80211_FREE(ic->ic_superg, M_80211_VAP);
129 		ic->ic_superg = NULL;
130 	}
131 }
132 
133 void
134 ieee80211_superg_vattach(struct ieee80211vap *vap)
135 {
136 	struct ieee80211com *ic = vap->iv_ic;
137 
138 	if (ic->ic_superg == NULL)	/* NB: can't do fast-frames w/o state */
139 		vap->iv_caps &= ~IEEE80211_C_FF;
140 	if (vap->iv_caps & IEEE80211_C_FF)
141 		vap->iv_flags |= IEEE80211_F_FF;
142 	/* NB: we only implement sta mode */
143 	if (vap->iv_opmode == IEEE80211_M_STA &&
144 	    (vap->iv_caps & IEEE80211_C_TURBOP))
145 		vap->iv_flags |= IEEE80211_F_TURBOP;
146 }
147 
148 void
149 ieee80211_superg_vdetach(struct ieee80211vap *vap)
150 {
151 }
152 
153 #define	ATH_OUI_BYTES		0x00, 0x03, 0x7f
154 /*
155  * Add a WME information element to a frame.
156  */
157 uint8_t *
158 ieee80211_add_ath(uint8_t *frm, uint8_t caps, ieee80211_keyix defkeyix)
159 {
160 	static const struct ieee80211_ath_ie info = {
161 		.ath_id		= IEEE80211_ELEMID_VENDOR,
162 		.ath_len	= sizeof(struct ieee80211_ath_ie) - 2,
163 		.ath_oui	= { ATH_OUI_BYTES },
164 		.ath_oui_type	= ATH_OUI_TYPE,
165 		.ath_oui_subtype= ATH_OUI_SUBTYPE,
166 		.ath_version	= ATH_OUI_VERSION,
167 	};
168 	struct ieee80211_ath_ie *ath = (struct ieee80211_ath_ie *) frm;
169 
170 	memcpy(frm, &info, sizeof(info));
171 	ath->ath_capability = caps;
172 	if (defkeyix != IEEE80211_KEYIX_NONE) {
173 		ath->ath_defkeyix[0] = (defkeyix & 0xff);
174 		ath->ath_defkeyix[1] = ((defkeyix >> 8) & 0xff);
175 	} else {
176 		ath->ath_defkeyix[0] = 0xff;
177 		ath->ath_defkeyix[1] = 0x7f;
178 	}
179 	return frm + sizeof(info);
180 }
181 #undef ATH_OUI_BYTES
182 
183 uint8_t *
184 ieee80211_add_athcaps(uint8_t *frm, const struct ieee80211_node *bss)
185 {
186 	const struct ieee80211vap *vap = bss->ni_vap;
187 
188 	return ieee80211_add_ath(frm,
189 	    vap->iv_flags & IEEE80211_F_ATHEROS,
190 	    ((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
191 	    bss->ni_authmode != IEEE80211_AUTH_8021X) ?
192 	    vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
193 }
194 
195 void
196 ieee80211_parse_ath(struct ieee80211_node *ni, uint8_t *ie)
197 {
198 	const struct ieee80211_ath_ie *ath =
199 		(const struct ieee80211_ath_ie *) ie;
200 
201 	ni->ni_ath_flags = ath->ath_capability;
202 	ni->ni_ath_defkeyix = le16dec(&ath->ath_defkeyix);
203 }
204 
205 int
206 ieee80211_parse_athparams(struct ieee80211_node *ni, uint8_t *frm,
207 	const struct ieee80211_frame *wh)
208 {
209 	struct ieee80211vap *vap = ni->ni_vap;
210 	const struct ieee80211_ath_ie *ath;
211 	u_int len = frm[1];
212 	int capschanged;
213 	uint16_t defkeyix;
214 
215 	if (len < sizeof(struct ieee80211_ath_ie)-2) {
216 		IEEE80211_DISCARD_IE(vap,
217 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_SUPERG,
218 		    wh, "Atheros", "too short, len %u", len);
219 		return -1;
220 	}
221 	ath = (const struct ieee80211_ath_ie *)frm;
222 	capschanged = (ni->ni_ath_flags != ath->ath_capability);
223 	defkeyix = le16dec(ath->ath_defkeyix);
224 	if (capschanged || defkeyix != ni->ni_ath_defkeyix) {
225 		ni->ni_ath_flags = ath->ath_capability;
226 		ni->ni_ath_defkeyix = defkeyix;
227 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
228 		    "ath ie change: new caps 0x%x defkeyix 0x%x",
229 		    ni->ni_ath_flags, ni->ni_ath_defkeyix);
230 	}
231 	if (IEEE80211_ATH_CAP(vap, ni, ATHEROS_CAP_TURBO_PRIME)) {
232 		uint16_t curflags, newflags;
233 
234 		/*
235 		 * Check for turbo mode switch.  Calculate flags
236 		 * for the new mode and effect the switch.
237 		 */
238 		newflags = curflags = vap->iv_ic->ic_bsschan->ic_flags;
239 		/* NB: BOOST is not in ic_flags, so get it from the ie */
240 		if (ath->ath_capability & ATHEROS_CAP_BOOST)
241 			newflags |= IEEE80211_CHAN_TURBO;
242 		else
243 			newflags &= ~IEEE80211_CHAN_TURBO;
244 		if (newflags != curflags)
245 			ieee80211_dturbo_switch(vap, newflags);
246 	}
247 	return capschanged;
248 }
249 
250 /*
251  * Decap the encapsulated frame pair and dispatch the first
252  * for delivery.  The second frame is returned for delivery
253  * via the normal path.
254  */
255 struct mbuf *
256 ieee80211_ff_decap(struct ieee80211_node *ni, struct mbuf *m)
257 {
258 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
259 #define	MS(x,f)	(((x) & f) >> f##_S)
260 	struct ieee80211vap *vap = ni->ni_vap;
261 	struct llc *llc;
262 	uint32_t ath;
263 	struct mbuf *n;
264 	int framelen;
265 
266 	/* NB: we assume caller does this check for us */
267 	KASSERT(IEEE80211_ATH_CAP(vap, ni, IEEE80211_NODE_FF),
268 	    ("ff not negotiated"));
269 	/*
270 	 * Check for fast-frame tunnel encapsulation.
271 	 */
272 	if (m->m_pkthdr.len < 3*FF_LLC_SIZE)
273 		return m;
274 	if (m->m_len < FF_LLC_SIZE &&
275 	    (m = m_pullup(m, FF_LLC_SIZE)) == NULL) {
276 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
277 		    ni->ni_macaddr, "fast-frame",
278 		    "%s", "m_pullup(llc) failed");
279 		vap->iv_stats.is_rx_tooshort++;
280 		return NULL;
281 	}
282 	llc = (struct llc *)(mtod(m, uint8_t *) +
283 	    sizeof(struct ether_header));
284 	if (llc->llc_snap.ether_type != htons(ATH_FF_ETH_TYPE))
285 		return m;
286 	m_adj(m, FF_LLC_SIZE);
287 	m_copydata(m, 0, sizeof(uint32_t), (caddr_t) &ath);
288 	if (MS(ath, ATH_FF_PROTO) != ATH_FF_PROTO_L2TUNNEL) {
289 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
290 		    ni->ni_macaddr, "fast-frame",
291 		    "unsupport tunnel protocol, header 0x%x", ath);
292 		vap->iv_stats.is_ff_badhdr++;
293 		m_freem(m);
294 		return NULL;
295 	}
296 	/* NB: skip header and alignment padding */
297 	m_adj(m, roundup(sizeof(uint32_t) - 2, 4) + 2);
298 
299 	vap->iv_stats.is_ff_decap++;
300 
301 	/*
302 	 * Decap the first frame, bust it apart from the
303 	 * second and deliver; then decap the second frame
304 	 * and return it to the caller for normal delivery.
305 	 */
306 	m = ieee80211_decap1(m, &framelen);
307 	if (m == NULL) {
308 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
309 		    ni->ni_macaddr, "fast-frame", "%s", "first decap failed");
310 		vap->iv_stats.is_ff_tooshort++;
311 		return NULL;
312 	}
313 	n = m_split(m, framelen, M_NOWAIT);
314 	if (n == NULL) {
315 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
316 		    ni->ni_macaddr, "fast-frame",
317 		    "%s", "unable to split encapsulated frames");
318 		vap->iv_stats.is_ff_split++;
319 		m_freem(m);			/* NB: must reclaim */
320 		return NULL;
321 	}
322 	/* XXX not right for WDS */
323 	vap->iv_deliver_data(vap, ni, m);	/* 1st of pair */
324 
325 	/*
326 	 * Decap second frame.
327 	 */
328 	m_adj(n, roundup2(framelen, 4) - framelen);	/* padding */
329 	n = ieee80211_decap1(n, &framelen);
330 	if (n == NULL) {
331 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
332 		    ni->ni_macaddr, "fast-frame", "%s", "second decap failed");
333 		vap->iv_stats.is_ff_tooshort++;
334 	}
335 	/* XXX verify framelen against mbuf contents */
336 	return n;				/* 2nd delivered by caller */
337 #undef MS
338 #undef FF_LLC_SIZE
339 }
340 
341 /*
342  * Fast frame encapsulation.  There must be two packets
343  * chained with m_nextpkt.  We do header adjustment for
344  * each, add the tunnel encapsulation, and then concatenate
345  * the mbuf chains to form a single frame for transmission.
346  */
347 struct mbuf *
348 ieee80211_ff_encap(struct ieee80211vap *vap, struct mbuf *m1, int hdrspace,
349 	struct ieee80211_key *key)
350 {
351 	struct mbuf *m2;
352 	struct ether_header eh1, eh2;
353 	struct llc *llc;
354 	struct mbuf *m;
355 	int pad;
356 
357 	m2 = m1->m_nextpkt;
358 	if (m2 == NULL) {
359 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
360 		    "%s: only one frame\n", __func__);
361 		goto bad;
362 	}
363 	m1->m_nextpkt = NULL;
364 
365 	/*
366 	 * Adjust to include 802.11 header requirement.
367 	 */
368 	KASSERT(m1->m_len >= sizeof(eh1), ("no ethernet header!"));
369 	ETHER_HEADER_COPY(&eh1, mtod(m1, caddr_t));
370 	m1 = ieee80211_mbuf_adjust(vap, hdrspace, key, m1);
371 	if (m1 == NULL) {
372 		printf("%s: failed initial mbuf_adjust\n", __func__);
373 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
374 		m_freem(m2);
375 		goto bad;
376 	}
377 
378 	/*
379 	 * Copy second frame's Ethernet header out of line
380 	 * and adjust for possible padding in case there isn't room
381 	 * at the end of first frame.
382 	 */
383 	KASSERT(m2->m_len >= sizeof(eh2), ("no ethernet header!"));
384 	ETHER_HEADER_COPY(&eh2, mtod(m2, caddr_t));
385 	m2 = ieee80211_mbuf_adjust(vap, 4, NULL, m2);
386 	if (m2 == NULL) {
387 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
388 		printf("%s: failed second \n", __func__);
389 		goto bad;
390 	}
391 
392 	/*
393 	 * Now do tunnel encapsulation.  First, each
394 	 * frame gets a standard encapsulation.
395 	 */
396 	m1 = ieee80211_ff_encap1(vap, m1, &eh1);
397 	if (m1 == NULL)
398 		goto bad;
399 	m2 = ieee80211_ff_encap1(vap, m2, &eh2);
400 	if (m2 == NULL)
401 		goto bad;
402 
403 	/*
404 	 * Pad leading frame to a 4-byte boundary.  If there
405 	 * is space at the end of the first frame, put it
406 	 * there; otherwise prepend to the front of the second
407 	 * frame.  We know doing the second will always work
408 	 * because we reserve space above.  We prefer appending
409 	 * as this typically has better DMA alignment properties.
410 	 */
411 	for (m = m1; m->m_next != NULL; m = m->m_next)
412 		;
413 	pad = roundup2(m1->m_pkthdr.len, 4) - m1->m_pkthdr.len;
414 	if (pad) {
415 		if (M_TRAILINGSPACE(m) < pad) {		/* prepend to second */
416 			m2->m_data -= pad;
417 			m2->m_len += pad;
418 			m2->m_pkthdr.len += pad;
419 		} else {				/* append to first */
420 			m->m_len += pad;
421 			m1->m_pkthdr.len += pad;
422 		}
423 	}
424 
425 	/*
426 	 * A-MSDU's are just appended; the "I'm A-MSDU!" bit is in the
427 	 * QoS header.
428 	 *
429 	 * XXX optimize by prepending together
430 	 */
431 	m->m_next = m2;			/* NB: last mbuf from above */
432 	m1->m_pkthdr.len += m2->m_pkthdr.len;
433 	M_PREPEND(m1, sizeof(uint32_t)+2, M_NOWAIT);
434 	if (m1 == NULL) {		/* XXX cannot happen */
435 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
436 		    "%s: no space for tunnel header\n", __func__);
437 		vap->iv_stats.is_tx_nobuf++;
438 		return NULL;
439 	}
440 	memset(mtod(m1, void *), 0, sizeof(uint32_t)+2);
441 
442 	M_PREPEND(m1, sizeof(struct llc), M_NOWAIT);
443 	if (m1 == NULL) {		/* XXX cannot happen */
444 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
445 		    "%s: no space for llc header\n", __func__);
446 		vap->iv_stats.is_tx_nobuf++;
447 		return NULL;
448 	}
449 	llc = mtod(m1, struct llc *);
450 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
451 	llc->llc_control = LLC_UI;
452 	llc->llc_snap.org_code[0] = ATH_FF_SNAP_ORGCODE_0;
453 	llc->llc_snap.org_code[1] = ATH_FF_SNAP_ORGCODE_1;
454 	llc->llc_snap.org_code[2] = ATH_FF_SNAP_ORGCODE_2;
455 	llc->llc_snap.ether_type = htons(ATH_FF_ETH_TYPE);
456 
457 	vap->iv_stats.is_ff_encap++;
458 
459 	return m1;
460 bad:
461 	vap->iv_stats.is_ff_encapfail++;
462 	if (m1 != NULL)
463 		m_freem(m1);
464 	if (m2 != NULL)
465 		m_freem(m2);
466 	return NULL;
467 }
468 
469 /*
470  * A-MSDU encapsulation.
471  *
472  * This assumes just two frames for now, since we're borrowing the
473  * same queuing code and infrastructure as fast-frames.
474  *
475  * There must be two packets chained with m_nextpkt.
476  * We do header adjustment for each, and then concatenate the mbuf chains
477  * to form a single frame for transmission.
478  */
479 struct mbuf *
480 ieee80211_amsdu_encap(struct ieee80211vap *vap, struct mbuf *m1, int hdrspace,
481 	struct ieee80211_key *key)
482 {
483 	struct mbuf *m2;
484 	struct ether_header eh1, eh2;
485 	struct mbuf *m;
486 	int pad;
487 
488 	m2 = m1->m_nextpkt;
489 	if (m2 == NULL) {
490 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
491 		    "%s: only one frame\n", __func__);
492 		goto bad;
493 	}
494 	m1->m_nextpkt = NULL;
495 
496 	/*
497 	 * Include A-MSDU header in adjusting header layout.
498 	 */
499 	KASSERT(m1->m_len >= sizeof(eh1), ("no ethernet header!"));
500 	ETHER_HEADER_COPY(&eh1, mtod(m1, caddr_t));
501 	m1 = ieee80211_mbuf_adjust(vap,
502 		hdrspace + sizeof(struct llc) + sizeof(uint32_t) +
503 		    sizeof(struct ether_header),
504 		key, m1);
505 	if (m1 == NULL) {
506 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
507 		m_freem(m2);
508 		goto bad;
509 	}
510 
511 	/*
512 	 * Copy second frame's Ethernet header out of line
513 	 * and adjust for encapsulation headers.  Note that
514 	 * we make room for padding in case there isn't room
515 	 * at the end of first frame.
516 	 */
517 	KASSERT(m2->m_len >= sizeof(eh2), ("no ethernet header!"));
518 	ETHER_HEADER_COPY(&eh2, mtod(m2, caddr_t));
519 	m2 = ieee80211_mbuf_adjust(vap, 4, NULL, m2);
520 	if (m2 == NULL) {
521 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
522 		goto bad;
523 	}
524 
525 	/*
526 	 * Now do tunnel encapsulation.  First, each
527 	 * frame gets a standard encapsulation.
528 	 */
529 	m1 = ieee80211_ff_encap1(vap, m1, &eh1);
530 	if (m1 == NULL)
531 		goto bad;
532 	m2 = ieee80211_ff_encap1(vap, m2, &eh2);
533 	if (m2 == NULL)
534 		goto bad;
535 
536 	/*
537 	 * Pad leading frame to a 4-byte boundary.  If there
538 	 * is space at the end of the first frame, put it
539 	 * there; otherwise prepend to the front of the second
540 	 * frame.  We know doing the second will always work
541 	 * because we reserve space above.  We prefer appending
542 	 * as this typically has better DMA alignment properties.
543 	 */
544 	for (m = m1; m->m_next != NULL; m = m->m_next)
545 		;
546 	pad = roundup2(m1->m_pkthdr.len, 4) - m1->m_pkthdr.len;
547 	if (pad) {
548 		if (M_TRAILINGSPACE(m) < pad) {		/* prepend to second */
549 			m2->m_data -= pad;
550 			m2->m_len += pad;
551 			m2->m_pkthdr.len += pad;
552 		} else {				/* append to first */
553 			m->m_len += pad;
554 			m1->m_pkthdr.len += pad;
555 		}
556 	}
557 
558 	/*
559 	 * Now, stick 'em together.
560 	 */
561 	m->m_next = m2;			/* NB: last mbuf from above */
562 	m1->m_pkthdr.len += m2->m_pkthdr.len;
563 
564 	vap->iv_stats.is_amsdu_encap++;
565 
566 	return m1;
567 bad:
568 	vap->iv_stats.is_amsdu_encapfail++;
569 	if (m1 != NULL)
570 		m_freem(m1);
571 	if (m2 != NULL)
572 		m_freem(m2);
573 	return NULL;
574 }
575 
576 
577 static void
578 ff_transmit(struct ieee80211_node *ni, struct mbuf *m)
579 {
580 	struct ieee80211vap *vap = ni->ni_vap;
581 	struct ieee80211com *ic = ni->ni_ic;
582 
583 	IEEE80211_TX_LOCK_ASSERT(ic);
584 
585 	/* encap and xmit */
586 	m = ieee80211_encap(vap, ni, m);
587 	if (m != NULL)
588 		(void) ieee80211_parent_xmitpkt(ic, m);
589 	else
590 		ieee80211_free_node(ni);
591 }
592 
593 /*
594  * Flush frames to device; note we re-use the linked list
595  * the frames were stored on and use the sentinel (unchanged)
596  * which may be non-NULL.
597  */
598 static void
599 ff_flush(struct mbuf *head, struct mbuf *last)
600 {
601 	struct mbuf *m, *next;
602 	struct ieee80211_node *ni;
603 	struct ieee80211vap *vap;
604 
605 	for (m = head; m != last; m = next) {
606 		next = m->m_nextpkt;
607 		m->m_nextpkt = NULL;
608 
609 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
610 		vap = ni->ni_vap;
611 
612 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
613 		    "%s: flush frame, age %u", __func__, M_AGE_GET(m));
614 		vap->iv_stats.is_ff_flush++;
615 
616 		ff_transmit(ni, m);
617 	}
618 }
619 
620 /*
621  * Age frames on the staging queue.
622  */
623 void
624 ieee80211_ff_age(struct ieee80211com *ic, struct ieee80211_stageq *sq,
625     int quanta)
626 {
627 	struct mbuf *m, *head;
628 	struct ieee80211_node *ni;
629 
630 	IEEE80211_FF_LOCK(ic);
631 	if (sq->depth == 0) {
632 		IEEE80211_FF_UNLOCK(ic);
633 		return;		/* nothing to do */
634 	}
635 
636 	KASSERT(sq->head != NULL, ("stageq empty"));
637 
638 	head = sq->head;
639 	while ((m = sq->head) != NULL && M_AGE_GET(m) < quanta) {
640 		int tid = WME_AC_TO_TID(M_WME_GETAC(m));
641 
642 		/* clear staging ref to frame */
643 		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
644 		KASSERT(ni->ni_tx_superg[tid] == m, ("staging queue empty"));
645 		ni->ni_tx_superg[tid] = NULL;
646 
647 		sq->head = m->m_nextpkt;
648 		sq->depth--;
649 	}
650 	if (m == NULL)
651 		sq->tail = NULL;
652 	else
653 		M_AGE_SUB(m, quanta);
654 	IEEE80211_FF_UNLOCK(ic);
655 
656 	IEEE80211_TX_LOCK(ic);
657 	ff_flush(head, m);
658 	IEEE80211_TX_UNLOCK(ic);
659 }
660 
661 static void
662 stageq_add(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *m)
663 {
664 	int age = ieee80211_ffagemax;
665 
666 	IEEE80211_FF_LOCK_ASSERT(ic);
667 
668 	if (sq->tail != NULL) {
669 		sq->tail->m_nextpkt = m;
670 		age -= M_AGE_GET(sq->head);
671 	} else
672 		sq->head = m;
673 	KASSERT(age >= 0, ("age %d", age));
674 	M_AGE_SET(m, age);
675 	m->m_nextpkt = NULL;
676 	sq->tail = m;
677 	sq->depth++;
678 }
679 
680 static void
681 stageq_remove(struct ieee80211com *ic, struct ieee80211_stageq *sq, struct mbuf *mstaged)
682 {
683 	struct mbuf *m, *mprev;
684 
685 	IEEE80211_FF_LOCK_ASSERT(ic);
686 
687 	mprev = NULL;
688 	for (m = sq->head; m != NULL; m = m->m_nextpkt) {
689 		if (m == mstaged) {
690 			if (mprev == NULL)
691 				sq->head = m->m_nextpkt;
692 			else
693 				mprev->m_nextpkt = m->m_nextpkt;
694 			if (sq->tail == m)
695 				sq->tail = mprev;
696 			sq->depth--;
697 			return;
698 		}
699 		mprev = m;
700 	}
701 	printf("%s: packet not found\n", __func__);
702 }
703 
704 static uint32_t
705 ff_approx_txtime(struct ieee80211_node *ni,
706 	const struct mbuf *m1, const struct mbuf *m2)
707 {
708 	struct ieee80211com *ic = ni->ni_ic;
709 	struct ieee80211vap *vap = ni->ni_vap;
710 	uint32_t framelen;
711 	uint32_t frame_time;
712 
713 	/*
714 	 * Approximate the frame length to be transmitted. A swag to add
715 	 * the following maximal values to the skb payload:
716 	 *   - 32: 802.11 encap + CRC
717 	 *   - 24: encryption overhead (if wep bit)
718 	 *   - 4 + 6: fast-frame header and padding
719 	 *   - 16: 2 LLC FF tunnel headers
720 	 *   - 14: 1 802.3 FF tunnel header (mbuf already accounts for 2nd)
721 	 */
722 	framelen = m1->m_pkthdr.len + 32 +
723 	    ATH_FF_MAX_HDR_PAD + ATH_FF_MAX_SEP_PAD + ATH_FF_MAX_HDR;
724 	if (vap->iv_flags & IEEE80211_F_PRIVACY)
725 		framelen += 24;
726 	if (m2 != NULL)
727 		framelen += m2->m_pkthdr.len;
728 
729 	/*
730 	 * For now, we assume non-shortgi, 20MHz, just because I want to
731 	 * at least test 802.11n.
732 	 */
733 	if (ni->ni_txrate & IEEE80211_RATE_MCS)
734 		frame_time = ieee80211_compute_duration_ht(framelen,
735 		    ni->ni_txrate,
736 		    IEEE80211_HT_RC_2_STREAMS(ni->ni_txrate),
737 		    0, /* isht40 */
738 		    0); /* isshortgi */
739 	else
740 		frame_time = ieee80211_compute_duration(ic->ic_rt, framelen,
741 			    ni->ni_txrate, 0);
742 	return (frame_time);
743 }
744 
745 /*
746  * Check if the supplied frame can be partnered with an existing
747  * or pending frame.  Return a reference to any frame that should be
748  * sent on return; otherwise return NULL.
749  */
750 struct mbuf *
751 ieee80211_ff_check(struct ieee80211_node *ni, struct mbuf *m)
752 {
753 	struct ieee80211vap *vap = ni->ni_vap;
754 	struct ieee80211com *ic = ni->ni_ic;
755 	struct ieee80211_superg *sg = ic->ic_superg;
756 	const int pri = M_WME_GETAC(m);
757 	struct ieee80211_stageq *sq;
758 	struct ieee80211_tx_ampdu *tap;
759 	struct mbuf *mstaged;
760 	uint32_t txtime, limit;
761 
762 	IEEE80211_TX_UNLOCK_ASSERT(ic);
763 
764 	IEEE80211_LOCK(ic);
765 	limit = IEEE80211_TXOP_TO_US(
766 	    ic->ic_wme.wme_chanParams.cap_wmeParams[pri].wmep_txopLimit);
767 	IEEE80211_UNLOCK(ic);
768 
769 	/*
770 	 * Check if the supplied frame can be aggregated.
771 	 *
772 	 * NB: we allow EAPOL frames to be aggregated with other ucast traffic.
773 	 *     Do 802.1x EAPOL frames proceed in the clear? Then they couldn't
774 	 *     be aggregated with other types of frames when encryption is on?
775 	 */
776 	IEEE80211_FF_LOCK(ic);
777 	tap = &ni->ni_tx_ampdu[WME_AC_TO_TID(pri)];
778 	mstaged = ni->ni_tx_superg[WME_AC_TO_TID(pri)];
779 	/* XXX NOTE: reusing packet counter state from A-MPDU */
780 	/*
781 	 * XXX NOTE: this means we're double-counting; it should just
782 	 * be done in ieee80211_output.c once for both superg and A-MPDU.
783 	 */
784 	ieee80211_txampdu_count_packet(tap);
785 
786 	/*
787 	 * When not in station mode never aggregate a multicast
788 	 * frame; this insures, for example, that a combined frame
789 	 * does not require multiple encryption keys.
790 	 */
791 	if (vap->iv_opmode != IEEE80211_M_STA &&
792 	    ETHER_IS_MULTICAST(mtod(m, struct ether_header *)->ether_dhost)) {
793 		/* XXX flush staged frame? */
794 		IEEE80211_FF_UNLOCK(ic);
795 		return m;
796 	}
797 	/*
798 	 * If there is no frame to combine with and the pps is
799 	 * too low; then do not attempt to aggregate this frame.
800 	 */
801 	if (mstaged == NULL &&
802 	    ieee80211_txampdu_getpps(tap) < ieee80211_ffppsmin) {
803 		IEEE80211_FF_UNLOCK(ic);
804 		return m;
805 	}
806 	sq = &sg->ff_stageq[pri];
807 	/*
808 	 * Check the txop limit to insure the aggregate fits.
809 	 */
810 	if (limit != 0 &&
811 	    (txtime = ff_approx_txtime(ni, m, mstaged)) > limit) {
812 		/*
813 		 * Aggregate too long, return to the caller for direct
814 		 * transmission.  In addition, flush any pending frame
815 		 * before sending this one.
816 		 */
817 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
818 		    "%s: txtime %u exceeds txop limit %u\n",
819 		    __func__, txtime, limit);
820 
821 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = NULL;
822 		if (mstaged != NULL)
823 			stageq_remove(ic, sq, mstaged);
824 		IEEE80211_FF_UNLOCK(ic);
825 
826 		if (mstaged != NULL) {
827 			IEEE80211_TX_LOCK(ic);
828 			IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
829 			    "%s: flush staged frame", __func__);
830 			/* encap and xmit */
831 			ff_transmit(ni, mstaged);
832 			IEEE80211_TX_UNLOCK(ic);
833 		}
834 		return m;		/* NB: original frame */
835 	}
836 	/*
837 	 * An aggregation candidate.  If there's a frame to partner
838 	 * with then combine and return for processing.  Otherwise
839 	 * save this frame and wait for a partner to show up (or
840 	 * the frame to be flushed).  Note that staged frames also
841 	 * hold their node reference.
842 	 */
843 	if (mstaged != NULL) {
844 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = NULL;
845 		stageq_remove(ic, sq, mstaged);
846 		IEEE80211_FF_UNLOCK(ic);
847 
848 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
849 		    "%s: aggregate fast-frame", __func__);
850 		/*
851 		 * Release the node reference; we only need
852 		 * the one already in mstaged.
853 		 */
854 		KASSERT(mstaged->m_pkthdr.rcvif == (void *)ni,
855 		    ("rcvif %p ni %p", mstaged->m_pkthdr.rcvif, ni));
856 		ieee80211_free_node(ni);
857 
858 		m->m_nextpkt = NULL;
859 		mstaged->m_nextpkt = m;
860 		mstaged->m_flags |= M_FF; /* NB: mark for encap work */
861 	} else {
862 		KASSERT(ni->ni_tx_superg[WME_AC_TO_TID(pri)] == NULL,
863 		    ("ni_tx_superg[]: %p",
864 		    ni->ni_tx_superg[WME_AC_TO_TID(pri)]));
865 		ni->ni_tx_superg[WME_AC_TO_TID(pri)] = m;
866 
867 		stageq_add(ic, sq, m);
868 		IEEE80211_FF_UNLOCK(ic);
869 
870 		IEEE80211_NOTE(vap, IEEE80211_MSG_SUPERG, ni,
871 		    "%s: stage frame, %u queued", __func__, sq->depth);
872 		/* NB: mstaged is NULL */
873 	}
874 	return mstaged;
875 }
876 
877 struct mbuf *
878 ieee80211_amsdu_check(struct ieee80211_node *ni, struct mbuf *m)
879 {
880 	/*
881 	 * XXX TODO: actually enforce the node support
882 	 * and HTCAP requirements for the maximum A-MSDU
883 	 * size.
884 	 */
885 
886 	/* First: software A-MSDU transmit? */
887 	if (! ieee80211_amsdu_tx_ok(ni))
888 		return (m);
889 
890 	/* Next - EAPOL? Nope, don't aggregate; we don't QoS encap them */
891 	if (m->m_flags & (M_EAPOL | M_MCAST | M_BCAST))
892 		return (m);
893 
894 	/* Next - needs to be a data frame, non-broadcast, etc */
895 	if (ETHER_IS_MULTICAST(mtod(m, struct ether_header *)->ether_dhost))
896 		return (m);
897 
898 	return (ieee80211_ff_check(ni, m));
899 }
900 
901 void
902 ieee80211_ff_node_init(struct ieee80211_node *ni)
903 {
904 	/*
905 	 * Clean FF state on re-associate.  This handles the case
906 	 * where a station leaves w/o notifying us and then returns
907 	 * before node is reaped for inactivity.
908 	 */
909 	ieee80211_ff_node_cleanup(ni);
910 }
911 
912 /*
913  * Note: this comlock acquisition LORs with the node lock:
914  *
915  * 1: sta_join1 -> NODE_LOCK -> node_free -> node_cleanup -> ff_node_cleanup -> COM_LOCK
916  * 2: TBD
917  */
918 void
919 ieee80211_ff_node_cleanup(struct ieee80211_node *ni)
920 {
921 	struct ieee80211com *ic = ni->ni_ic;
922 	struct ieee80211_superg *sg = ic->ic_superg;
923 	struct mbuf *m, *next_m, *head;
924 	int tid;
925 
926 	IEEE80211_FF_LOCK(ic);
927 	head = NULL;
928 	for (tid = 0; tid < WME_NUM_TID; tid++) {
929 		int ac = TID_TO_WME_AC(tid);
930 		/*
931 		 * XXX Initialise the packet counter.
932 		 *
933 		 * This may be double-work for 11n stations;
934 		 * but without it we never setup things.
935 		 */
936 		ieee80211_txampdu_init_pps(&ni->ni_tx_ampdu[tid]);
937 		m = ni->ni_tx_superg[tid];
938 		if (m != NULL) {
939 			ni->ni_tx_superg[tid] = NULL;
940 			stageq_remove(ic, &sg->ff_stageq[ac], m);
941 			m->m_nextpkt = head;
942 			head = m;
943 		}
944 	}
945 	IEEE80211_FF_UNLOCK(ic);
946 
947 	/*
948 	 * Free mbufs, taking care to not dereference the mbuf after
949 	 * we free it (hence grabbing m_nextpkt before we free it.)
950 	 */
951 	m = head;
952 	while (m != NULL) {
953 		next_m = m->m_nextpkt;
954 		m_freem(m);
955 		ieee80211_free_node(ni);
956 		m = next_m;
957 	}
958 }
959 
960 /*
961  * Switch between turbo and non-turbo operating modes.
962  * Use the specified channel flags to locate the new
963  * channel, update 802.11 state, and then call back into
964  * the driver to effect the change.
965  */
966 void
967 ieee80211_dturbo_switch(struct ieee80211vap *vap, int newflags)
968 {
969 	struct ieee80211com *ic = vap->iv_ic;
970 	struct ieee80211_channel *chan;
971 
972 	chan = ieee80211_find_channel(ic, ic->ic_bsschan->ic_freq, newflags);
973 	if (chan == NULL) {		/* XXX should not happen */
974 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
975 		    "%s: no channel with freq %u flags 0x%x\n",
976 		    __func__, ic->ic_bsschan->ic_freq, newflags);
977 		return;
978 	}
979 
980 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SUPERG,
981 	    "%s: %s -> %s (freq %u flags 0x%x)\n", __func__,
982 	    ieee80211_phymode_name[ieee80211_chan2mode(ic->ic_bsschan)],
983 	    ieee80211_phymode_name[ieee80211_chan2mode(chan)],
984 	    chan->ic_freq, chan->ic_flags);
985 
986 	ic->ic_bsschan = chan;
987 	ic->ic_prevchan = ic->ic_curchan;
988 	ic->ic_curchan = chan;
989 	ic->ic_rt = ieee80211_get_ratetable(chan);
990 	ic->ic_set_channel(ic);
991 	ieee80211_radiotap_chan_change(ic);
992 	/* NB: do not need to reset ERP state 'cuz we're in sta mode */
993 }
994 
995 /*
996  * Return the current ``state'' of an Atheros capbility.
997  * If associated in station mode report the negotiated
998  * setting. Otherwise report the current setting.
999  */
1000 static int
1001 getathcap(struct ieee80211vap *vap, int cap)
1002 {
1003 	if (vap->iv_opmode == IEEE80211_M_STA &&
1004 	    vap->iv_state == IEEE80211_S_RUN)
1005 		return IEEE80211_ATH_CAP(vap, vap->iv_bss, cap) != 0;
1006 	else
1007 		return (vap->iv_flags & cap) != 0;
1008 }
1009 
1010 static int
1011 superg_ioctl_get80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
1012 {
1013 	switch (ireq->i_type) {
1014 	case IEEE80211_IOC_FF:
1015 		ireq->i_val = getathcap(vap, IEEE80211_F_FF);
1016 		break;
1017 	case IEEE80211_IOC_TURBOP:
1018 		ireq->i_val = getathcap(vap, IEEE80211_F_TURBOP);
1019 		break;
1020 	default:
1021 		return ENOSYS;
1022 	}
1023 	return 0;
1024 }
1025 IEEE80211_IOCTL_GET(superg, superg_ioctl_get80211);
1026 
1027 static int
1028 superg_ioctl_set80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
1029 {
1030 	switch (ireq->i_type) {
1031 	case IEEE80211_IOC_FF:
1032 		if (ireq->i_val) {
1033 			if ((vap->iv_caps & IEEE80211_C_FF) == 0)
1034 				return EOPNOTSUPP;
1035 			vap->iv_flags |= IEEE80211_F_FF;
1036 		} else
1037 			vap->iv_flags &= ~IEEE80211_F_FF;
1038 		return ENETRESET;
1039 	case IEEE80211_IOC_TURBOP:
1040 		if (ireq->i_val) {
1041 			if ((vap->iv_caps & IEEE80211_C_TURBOP) == 0)
1042 				return EOPNOTSUPP;
1043 			vap->iv_flags |= IEEE80211_F_TURBOP;
1044 		} else
1045 			vap->iv_flags &= ~IEEE80211_F_TURBOP;
1046 		return ENETRESET;
1047 	default:
1048 		return ENOSYS;
1049 	}
1050 }
1051 IEEE80211_IOCTL_SET(superg, superg_ioctl_set80211);
1052 
1053 #endif	/* IEEE80211_SUPPORT_SUPERG */
1054