/*- * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __FBSDID("$FreeBSD: head/sys/net80211/ieee80211_power.c 178354 2008-04-20 20:35:46Z sam $"); /* * IEEE 802.11 power save support. */ #include "opt_wlan.h" #include #include #include #include #include #include #include #include #include static void ieee80211_update_ps(struct ieee80211vap *, int); static int ieee80211_set_tim(struct ieee80211_node *, int); MALLOC_DEFINE(M_80211_POWER, "80211power", "802.11 power save state"); void ieee80211_power_attach(struct ieee80211com *ic) { } void ieee80211_power_detach(struct ieee80211com *ic) { } void ieee80211_power_vattach(struct ieee80211vap *vap) { if (vap->iv_opmode == IEEE80211_M_HOSTAP || vap->iv_opmode == IEEE80211_M_IBSS) { /* NB: driver should override */ vap->iv_update_ps = ieee80211_update_ps; vap->iv_set_tim = ieee80211_set_tim; } } void ieee80211_power_latevattach(struct ieee80211vap *vap) { /* * Allocate these only if needed. Beware that we * know adhoc mode doesn't support ATIM yet... */ if (vap->iv_opmode == IEEE80211_M_HOSTAP) { vap->iv_tim_len = howmany(vap->iv_max_aid,8) * sizeof(uint8_t); MALLOC(vap->iv_tim_bitmap, uint8_t *, vap->iv_tim_len, M_80211_POWER, M_NOWAIT | M_ZERO); if (vap->iv_tim_bitmap == NULL) { printf("%s: no memory for TIM bitmap!\n", __func__); /* XXX good enough to keep from crashing? */ vap->iv_tim_len = 0; } } } void ieee80211_power_vdetach(struct ieee80211vap *vap) { if (vap->iv_tim_bitmap != NULL) { FREE(vap->iv_tim_bitmap, M_80211_POWER); vap->iv_tim_bitmap = NULL; } } /* * Clear any frames queued on a node's power save queue. * The number of frames that were present is returned. */ int ieee80211_node_saveq_drain(struct ieee80211_node *ni) { int qlen; IEEE80211_NODE_SAVEQ_LOCK(ni); qlen = IEEE80211_NODE_SAVEQ_QLEN(ni); _IF_DRAIN(&ni->ni_savedq); IEEE80211_NODE_SAVEQ_UNLOCK(ni); return qlen; } /* * Age frames on the power save queue. The aging interval is * 4 times the listen interval specified by the station. This * number is factored into the age calculations when the frame * is placed on the queue. We store ages as time differences * so we can check and/or adjust only the head of the list. * If a frame's age exceeds the threshold then discard it. * The number of frames discarded is returned so the caller * can check if it needs to adjust the tim. */ int ieee80211_node_saveq_age(struct ieee80211_node *ni) { int discard = 0; if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) { #ifdef IEEE80211_DEBUG struct ieee80211vap *vap = ni->ni_vap; #endif struct mbuf *m; IEEE80211_NODE_SAVEQ_LOCK(ni); while (IF_POLL(&ni->ni_savedq, m) != NULL && M_AGE_GET(m) < IEEE80211_INACT_WAIT) { IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "discard frame, age %u", M_AGE_GET(m)); _IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m); m_freem(m); discard++; } if (m != NULL) M_AGE_SUB(m, IEEE80211_INACT_WAIT); IEEE80211_NODE_SAVEQ_UNLOCK(ni); IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "discard %u frames for age", discard); IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard); } return discard; } /* * Handle a change in the PS station occupancy. */ static void ieee80211_update_ps(struct ieee80211vap *vap, int nsta) { KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP || vap->iv_opmode == IEEE80211_M_IBSS, ("operating mode %u", vap->iv_opmode)); } /* * Indicate whether there are frames queued for a station in power-save mode. */ static int ieee80211_set_tim(struct ieee80211_node *ni, int set) { struct ieee80211vap *vap = ni->ni_vap; struct ieee80211com *ic = ni->ni_ic; uint16_t aid; int changed; KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP || vap->iv_opmode == IEEE80211_M_IBSS, ("operating mode %u", vap->iv_opmode)); aid = IEEE80211_AID(ni->ni_associd); KASSERT(aid < vap->iv_max_aid, ("bogus aid %u, max %u", aid, vap->iv_max_aid)); IEEE80211_LOCK(ic); changed = (set != (isset(vap->iv_tim_bitmap, aid) != 0)); if (changed) { if (set) { setbit(vap->iv_tim_bitmap, aid); vap->iv_ps_pending++; } else { clrbit(vap->iv_tim_bitmap, aid); vap->iv_ps_pending--; } /* NB: we know vap is in RUN state so no need to check */ vap->iv_update_beacon(vap, IEEE80211_BEACON_TIM); } IEEE80211_UNLOCK(ic); return changed; } /* * Save an outbound packet for a node in power-save sleep state. * The new packet is placed on the node's saved queue, and the TIM * is changed, if necessary. */ void ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m) { struct ieee80211vap *vap = ni->ni_vap; struct ieee80211com *ic = ni->ni_ic; int qlen, age; IEEE80211_NODE_SAVEQ_LOCK(ni); if (_IF_QFULL(&ni->ni_savedq)) { _IF_DROP(&ni->ni_savedq); IEEE80211_NODE_SAVEQ_UNLOCK(ni); IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni, "pwr save q overflow, drops %d (size %d)", ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE); #ifdef IEEE80211_DEBUG if (ieee80211_msg_dumppkts(vap)) ieee80211_dump_pkt(ni->ni_ic, mtod(m, caddr_t), m->m_len, -1, -1); #endif m_freem(m); return; } /* * Tag the frame with it's expiry time and insert * it in the queue. The aging interval is 4 times * the listen interval specified by the station. * Frames that sit around too long are reclaimed * using this information. */ /* TU -> secs. XXX handle overflow? */ age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000; _IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age); IEEE80211_NODE_SAVEQ_UNLOCK(ni); IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "save frame with age %d, %u now queued", age, qlen); if (qlen == 1 && vap->iv_set_tim != NULL) vap->iv_set_tim(ni, 1); } /* * Unload the frames from the ps q but don't send them * to the driver yet. We do this in two stages to minimize * locking but also because there's no easy way to preserve * ordering given the existing ifnet access mechanisms. * XXX could be optimized */ static void pwrsave_flushq(struct ieee80211_node *ni) { struct mbuf *m, *mhead, *mtail; int mcount; IEEE80211_NODE_SAVEQ_LOCK(ni); mcount = IEEE80211_NODE_SAVEQ_QLEN(ni); mhead = mtail = NULL; for (;;) { _IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m); if (m == NULL) break; if (mhead == NULL) { mhead = m; m->m_nextpkt = NULL; } else mtail->m_nextpkt = m; mtail = m; } IEEE80211_NODE_SAVEQ_UNLOCK(ni); if (mhead != NULL) { /* XXX need different driver interface */ /* XXX bypasses q max and OACTIVE */ struct ifnet *ifp = ni->ni_vap->iv_ifp; IF_PREPEND_LIST(&ifp->if_snd, mhead, mtail, mcount); if_start(ifp); } } /* * Handle station power-save state change. */ void ieee80211_node_pwrsave(struct ieee80211_node *ni, int enable) { struct ieee80211vap *vap = ni->ni_vap; int update; update = 0; if (enable) { if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) { vap->iv_ps_sta++; update = 1; } ni->ni_flags |= IEEE80211_NODE_PWR_MGT; IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "power save mode on, %u sta's in ps mode", vap->iv_ps_sta); if (update) vap->iv_update_ps(vap, vap->iv_ps_sta); } else { if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) { vap->iv_ps_sta--; update = 1; } ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT; IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "power save mode off, %u sta's in ps mode", vap->iv_ps_sta); /* NB: order here is intentional so TIM is clear before flush */ if (vap->iv_set_tim != NULL) vap->iv_set_tim(ni, 0); if (update) { /* NB if no sta's in ps, driver should flush mc q */ vap->iv_update_ps(vap, vap->iv_ps_sta); } pwrsave_flushq(ni); } } /* * Handle power-save state change in station mode. */ void ieee80211_sta_pwrsave(struct ieee80211vap *vap, int enable) { struct ieee80211_node *ni = vap->iv_bss; int qlen; if (!((enable != 0) ^ ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) != 0))) return; IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "sta power save mode %s", enable ? "on" : "off"); if (!enable) { ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT; ieee80211_send_nulldata(ieee80211_ref_node(ni)); /* * Flush any queued frames; we can do this immediately * because we know they'll be queued behind the null * data frame we send the ap. * XXX can we use a data frame to take us out of ps? */ qlen = IEEE80211_NODE_SAVEQ_QLEN(ni); if (qlen != 0) { IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, "flush ps queue, %u packets queued", qlen); pwrsave_flushq(ni); } } else { ni->ni_flags |= IEEE80211_NODE_PWR_MGT; ieee80211_send_nulldata(ieee80211_ref_node(ni)); } }