2 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
25 * $FreeBSD: head/sys/net80211/ieee80211_power.c 186302 2008-12-18 23:00:09Z sam $
29 * IEEE 802.11 power save support.
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
37 #include <sys/socket.h>
40 #include <net/if_media.h>
41 #include <net/ethernet.h>
42 #include <net/route.h>
44 #include <netproto/802_11/ieee80211_var.h>
48 static void ieee80211_update_ps(struct ieee80211vap *, int);
49 static int ieee80211_set_tim(struct ieee80211_node *, int);
51 MALLOC_DEFINE(M_80211_POWER, "80211power", "802.11 power save state");
54 ieee80211_power_attach(struct ieee80211com *ic)
59 ieee80211_power_detach(struct ieee80211com *ic)
64 ieee80211_power_vattach(struct ieee80211vap *vap)
66 if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
67 vap->iv_opmode == IEEE80211_M_IBSS) {
68 /* NB: driver should override */
69 vap->iv_update_ps = ieee80211_update_ps;
70 vap->iv_set_tim = ieee80211_set_tim;
75 ieee80211_power_latevattach(struct ieee80211vap *vap)
78 * Allocate these only if needed. Beware that we
79 * know adhoc mode doesn't support ATIM yet...
81 if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
82 vap->iv_tim_len = howmany(vap->iv_max_aid,8) * sizeof(uint8_t);
83 vap->iv_tim_bitmap = (uint8_t *) kmalloc(vap->iv_tim_len,
84 M_80211_POWER, M_INTWAIT | M_ZERO);
85 if (vap->iv_tim_bitmap == NULL) {
86 kprintf("%s: no memory for TIM bitmap!\n", __func__);
87 /* XXX good enough to keep from crashing? */
94 ieee80211_power_vdetach(struct ieee80211vap *vap)
96 if (vap->iv_tim_bitmap != NULL) {
97 kfree(vap->iv_tim_bitmap, M_80211_POWER);
98 vap->iv_tim_bitmap = NULL;
103 ieee80211_psq_init(struct ieee80211_psq *psq, const char *name)
105 memset(psq, 0, sizeof(*psq));
106 psq->psq_maxlen = IEEE80211_PS_MAX_QUEUE;
110 ieee80211_psq_cleanup(struct ieee80211_psq *psq)
113 psq_drain(psq); /* XXX should not be needed? */
115 KASSERT(psq->psq_len == 0, ("%d frames on ps q", psq->psq_len));
120 * Return the highest priority frame in the ps queue.
123 ieee80211_node_psq_dequeue(struct ieee80211_node *ni, int *qlen)
125 struct ieee80211_psq *psq = &ni->ni_psq;
126 struct ieee80211_psq_head *qhead;
129 qhead = &psq->psq_head[0];
131 if ((m = qhead->head) != NULL) {
132 if ((qhead->head = m->m_nextpkt) == NULL)
134 KASSERT(qhead->len > 0, ("qhead len %d", qhead->len));
136 KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len));
140 if (m == NULL && qhead == &psq->psq_head[0]) {
141 /* Algol-68 style for loop */
142 qhead = &psq->psq_head[1];
146 *qlen = psq->psq_len;
151 * Reclaim an mbuf from the ps q. If marked with M_ENCAP
152 * we assume there is a node reference that must be relcaimed.
155 psq_mfree(struct mbuf *m)
157 if (m->m_flags & M_ENCAP) {
158 struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif;
159 ieee80211_free_node(ni);
166 * Clear any frames queued in the power save queue.
167 * The number of frames that were present is returned.
170 psq_drain(struct ieee80211_psq *psq)
172 struct ieee80211_psq_head *qhead;
177 qhead = &psq->psq_head[0];
179 while ((m = qhead->head) != NULL) {
180 qhead->head = m->m_nextpkt;
185 if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */
186 qhead = &psq->psq_head[1];
195 * Clear any frames queued in the power save queue.
196 * The number of frames that were present is returned.
199 ieee80211_node_psq_drain(struct ieee80211_node *ni)
201 return psq_drain(&ni->ni_psq);
205 * Age frames on the power save queue. The aging interval is
206 * 4 times the listen interval specified by the station. This
207 * number is factored into the age calculations when the frame
208 * is placed on the queue. We store ages as time differences
209 * so we can check and/or adjust only the head of the list.
210 * If a frame's age exceeds the threshold then discard it.
211 * The number of frames discarded is returned so the caller
212 * can check if it needs to adjust the tim.
215 ieee80211_node_psq_age(struct ieee80211_node *ni)
217 struct ieee80211_psq *psq = &ni->ni_psq;
220 if (psq->psq_len != 0) {
221 #ifdef IEEE80211_DEBUG
222 struct ieee80211vap *vap = ni->ni_vap;
224 struct ieee80211_psq_head *qhead;
227 qhead = &psq->psq_head[0];
229 while ((m = qhead->head) != NULL &&
230 M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
231 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
232 "discard frame, age %u", M_AGE_GET(m));
233 if ((qhead->head = m->m_nextpkt) == NULL)
235 KASSERT(qhead->len > 0, ("qhead len %d", qhead->len));
237 KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len));
242 if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */
243 qhead = &psq->psq_head[1];
247 M_AGE_SUB(m, IEEE80211_INACT_WAIT);
249 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
250 "discard %u frames for age", discard);
251 IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard);
257 * Handle a change in the PS station occupancy.
260 ieee80211_update_ps(struct ieee80211vap *vap, int nsta)
263 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP ||
264 vap->iv_opmode == IEEE80211_M_IBSS,
265 ("operating mode %u", vap->iv_opmode));
269 * Indicate whether there are frames queued for a station in power-save mode.
272 ieee80211_set_tim(struct ieee80211_node *ni, int set)
274 struct ieee80211vap *vap = ni->ni_vap;
275 struct ieee80211com *ic = ni->ni_ic;
280 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP ||
281 vap->iv_opmode == IEEE80211_M_IBSS,
282 ("operating mode %u", vap->iv_opmode));
284 aid = IEEE80211_AID(ni->ni_associd);
285 KASSERT(aid < vap->iv_max_aid,
286 ("bogus aid %u, max %u", aid, vap->iv_max_aid));
288 changed = (set != (isset(vap->iv_tim_bitmap, aid) != 0));
291 setbit(vap->iv_tim_bitmap, aid);
292 vap->iv_ps_pending++;
294 clrbit(vap->iv_tim_bitmap, aid);
295 vap->iv_ps_pending--;
297 /* NB: we know vap is in RUN state so no need to check */
298 vap->iv_update_beacon(vap, IEEE80211_BEACON_TIM);
305 * Save an outbound packet for a node in power-save sleep state.
306 * The new packet is placed on the node's saved queue, and the TIM
307 * is changed, if necessary.
310 ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m)
312 struct ieee80211_psq *psq = &ni->ni_psq;
313 struct ieee80211vap *vap = ni->ni_vap;
314 struct ieee80211com *ic = ni->ni_ic;
315 struct ieee80211_psq_head *qhead;
318 if (psq->psq_len >= psq->psq_maxlen) {
320 IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
321 "pwr save q overflow, drops %d (size %d)",
322 psq->psq_drops, psq->psq_len);
323 #ifdef IEEE80211_DEBUG
324 if (ieee80211_msg_dumppkts(vap))
325 ieee80211_dump_pkt(ni->ni_ic, mtod(m, caddr_t),
332 * Tag the frame with it's expiry time and insert it in
333 * the appropriate queue. The aging interval is 4 times
334 * the listen interval specified by the station. Frames
335 * that sit around too long are reclaimed using this
338 /* TU -> secs. XXX handle overflow? */
339 age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000;
341 * Encapsulated frames go on the high priority queue,
342 * other stuff goes on the low priority queue. We use
343 * this to order frames returned out of the driver
344 * ahead of frames we collect in ieee80211_start.
346 if (m->m_flags & M_ENCAP)
347 qhead = &psq->psq_head[0];
349 qhead = &psq->psq_head[1];
350 if (qhead->tail == NULL) {
355 * Take care to adjust age when inserting the first
356 * frame of a queue and the other queue already has
357 * frames. We need to preserve the age difference
358 * relationship so ieee80211_node_psq_age works.
360 if (qhead == &psq->psq_head[1]) {
361 mh = psq->psq_head[0].head;
365 mh = psq->psq_head[1].head;
367 int nage = M_AGE_GET(mh) - age;
368 /* XXX is clamping to zero good 'nuf? */
369 M_AGE_SET(mh, nage < 0 ? 0 : nage);
373 qhead->tail->m_nextpkt = m;
374 age -= M_AGE_GET(qhead->head);
376 KASSERT(age >= 0, ("age %d", age));
381 qlen = ++(psq->psq_len);
383 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
384 "save frame with age %d, %u now queued", age, qlen);
386 if (qlen == 1 && vap->iv_set_tim != NULL)
387 vap->iv_set_tim(ni, 1);
393 * Move frames from the ps q to the vap's send queue
394 * and/or the driver's send queue; and kick the start
395 * method for each, as appropriate. Note we're careful
396 * to preserve packet ordering here.
399 pwrsave_flushq(struct ieee80211_node *ni)
401 struct ieee80211_psq *psq = &ni->ni_psq;
402 struct ieee80211vap *vap = ni->ni_vap;
403 struct ieee80211_psq_head *qhead;
404 struct ifnet *parent, *ifp;
406 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
407 "flush ps queue, %u packets queued", psq->psq_len);
409 qhead = &psq->psq_head[0]; /* 802.11 frames */
410 if (qhead->head != NULL) {
411 /* XXX could dispatch through vap and check M_ENCAP */
412 parent = vap->iv_ic->ic_ifp;
413 /* XXX need different driver interface */
414 /* XXX bypasses q max and OACTIVE */
415 IF_PREPEND_LIST(&parent->if_snd, qhead->head, qhead->tail,
417 qhead->head = qhead->tail = NULL;
422 qhead = &psq->psq_head[1]; /* 802.3 frames */
423 if (qhead->head != NULL) {
425 /* XXX need different driver interface */
426 /* XXX bypasses q max and OACTIVE */
427 IF_PREPEND_LIST(&ifp->if_snd, qhead->head, qhead->tail,
429 qhead->head = qhead->tail = NULL;
435 /* NB: do this outside the psq lock */
436 /* XXX packets might get reordered if parent is OACTIVE */
438 parent->if_start(parent);
444 * Handle station power-save state change.
447 ieee80211_node_pwrsave(struct ieee80211_node *ni, int enable)
449 struct ieee80211vap *vap = ni->ni_vap;
454 if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
458 ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
459 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
460 "power save mode on, %u sta's in ps mode", vap->iv_ps_sta);
463 vap->iv_update_ps(vap, vap->iv_ps_sta);
465 if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
469 ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
470 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
471 "power save mode off, %u sta's in ps mode", vap->iv_ps_sta);
473 /* NB: order here is intentional so TIM is clear before flush */
474 if (vap->iv_set_tim != NULL)
475 vap->iv_set_tim(ni, 0);
477 /* NB if no sta's in ps, driver should flush mc q */
478 vap->iv_update_ps(vap, vap->iv_ps_sta);
480 if (ni->ni_psq.psq_len != 0)
486 * Handle power-save state change in station mode.
489 ieee80211_sta_pwrsave(struct ieee80211vap *vap, int enable)
491 struct ieee80211_node *ni = vap->iv_bss;
493 if (!((enable != 0) ^ ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) != 0)))
496 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
497 "sta power save mode %s", enable ? "on" : "off");
499 ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
500 ieee80211_send_nulldata(ieee80211_ref_node(ni));
502 * Flush any queued frames; we can do this immediately
503 * because we know they'll be queued behind the null
504 * data frame we send the ap.
505 * XXX can we use a data frame to take us out of ps?
507 if (ni->ni_psq.psq_len != 0)
510 ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
511 ieee80211_send_nulldata(ieee80211_ref_node(ni));