/*- * Copyright (c) 2001 Atsushi Onoe * Copyright (c) 2002-2005 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. * 3. The name of the author may not be used to endorse or promote products *    derived from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * 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. * * $Id: ieee80211_power.c 1637 2006-06-10 02:17:05Z mentor $ */#ifndef EXPORT_SYMTAB#define	EXPORT_SYMTAB#endif/* * IEEE 802.11 power save support. */#include <linux/config.h>#include <linux/version.h>#include <linux/module.h>#include <linux/skbuff.h>#include <linux/netdevice.h>#include <linux/etherdevice.h>#include "if_media.h"#include <net80211/ieee80211_var.h>#include <net80211/ieee80211_proto.h>static void ieee80211_set_tim(struct ieee80211_node *ni, int set);voidieee80211_power_attach(struct ieee80211com *ic){}voidieee80211_power_detach(struct ieee80211com *ic){}voidieee80211_power_vattach(struct ieee80211vap *vap){	if (vap->iv_opmode == IEEE80211_M_HOSTAP ||	    vap->iv_opmode == IEEE80211_M_IBSS) {		/* NB: driver should override */		vap->iv_set_tim = ieee80211_set_tim;	}}voidieee80211_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(u_int8_t);		MALLOC(vap->iv_tim_bitmap, u_int8_t *, vap->iv_tim_len,			M_DEVBUF, 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;		}	}}voidieee80211_power_vdetach(struct ieee80211vap *vap){	if (vap->iv_tim_bitmap != NULL) {		FREE(vap->iv_tim_bitmap, M_DEVBUF);		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. */intieee80211_node_saveq_drain(struct ieee80211_node *ni){	struct sk_buff *skb;	int qlen;	IEEE80211_NODE_SAVEQ_LOCK(ni);	qlen = skb_queue_len(&ni->ni_savedq);	while ((skb = __skb_dequeue(&ni->ni_savedq)) != NULL) {		ieee80211_free_node(ni);		dev_kfree_skb_any(skb);	}	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. */intieee80211_node_saveq_age(struct ieee80211_node *ni){	int discard = 0;	/* XXX racey but good 'nuf? */	if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {#ifdef IEEE80211_DEBUG		struct ieee80211vap *vap = ni->ni_vap;#endif		struct sk_buff *skb;		IEEE80211_NODE_SAVEQ_LOCK(ni);		while ((skb = skb_peek(&ni->ni_savedq)) != NULL &&		     M_AGE_GET(skb) < IEEE80211_INACT_WAIT) {			IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,				"discard frame, age %u", M_AGE_GET(skb));			skb = __skb_dequeue(&ni->ni_savedq);			dev_kfree_skb_any(skb);			discard++;		}		if (skb != NULL)			M_AGE_SUB(skb, 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;}/* * Indicate whether there are frames queued for a station in power-save mode. */static voidieee80211_set_tim(struct ieee80211_node *ni, int set){	struct ieee80211vap *vap = ni->ni_vap;	u_int16_t aid;	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(ni->ni_ic);	if (set != (isset(vap->iv_tim_bitmap, aid) != 0)) {		if (set) {			setbit(vap->iv_tim_bitmap, aid);			vap->iv_ps_pending++;		} else {			clrbit(vap->iv_tim_bitmap, aid);			vap->iv_ps_pending--;		}		vap->iv_flags |= IEEE80211_F_TIMUPDATE;	}	IEEE80211_UNLOCK(ni->ni_ic);}/* * 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. */voidieee80211_pwrsave(struct ieee80211_node *ni, struct sk_buff *skb){	struct ieee80211vap *vap = ni->ni_vap;	struct ieee80211com *ic = ni->ni_ic;	unsigned long flags;	struct sk_buff *tail;	int qlen, age;	spin_lock_irqsave(&ni->ni_savedq.lock, flags);	if (skb_queue_len(&ni->ni_savedq) >= IEEE80211_PS_MAX_QUEUE) {		IEEE80211_NODE_STAT(ni, psq_drops);		spin_unlock_irqrestore(&ni->ni_savedq.lock, flags);		IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,			"pwr save q overflow, drops %d (size %d)",			ni->ni_stats.ns_psq_drops, IEEE80211_PS_MAX_QUEUE);#ifdef IEEE80211_DEBUG		if (ieee80211_msg_dumppkts(vap))			ieee80211_dump_pkt(ni->ni_ic, skb->data, skb->len, -1, -1);#endif		dev_kfree_skb(skb);		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.	 */	/* XXX handle overflow? */	age = ((ni->ni_intval * ic->ic_lintval) << 2) / 1024; /* TU -> secs */	tail = skb_peek_tail(&ni->ni_savedq);	if (tail != NULL) {		age -= M_AGE_GET(tail);		__skb_append(tail, skb, &ni->ni_savedq);	} else		__skb_queue_head(&ni->ni_savedq, skb);	M_AGE_SET(skb, age);	qlen = skb_queue_len(&ni->ni_savedq);	spin_unlock_irqrestore(&ni->ni_savedq.lock, flags);	IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,		"save frame, %u now queued", qlen);	if (qlen == 1 && vap->iv_set_tim != NULL)		vap->iv_set_tim(ni, 1);}/* * Handle power-save state change in ap/ibss mode. */voidieee80211_node_pwrsave(struct ieee80211_node *ni, int enable){	struct ieee80211vap *vap = ni->ni_vap;	KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP ||		vap->iv_opmode == IEEE80211_M_IBSS,		("unexpected operating mode %u", vap->iv_opmode));	if (enable) {		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0)			vap->iv_ps_sta++;		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);		return;	}	if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT))		vap->iv_ps_sta--;	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);	/* XXX if no stations in ps mode, flush mc frames */	/*	 * Flush queued unicast frames.	 */	if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0) {		if (vap->iv_set_tim != NULL)			vap->iv_set_tim(ni, 0);		/* just in case */		return;	}	IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,		"flush ps queue, %u packets queued",		IEEE80211_NODE_SAVEQ_QLEN(ni));	for (;;) {		struct sk_buff *skb;		int qlen;		IEEE80211_NODE_SAVEQ_LOCK(ni);		IEEE80211_NODE_SAVEQ_DEQUEUE(ni, skb, qlen);		IEEE80211_NODE_SAVEQ_UNLOCK(ni);		if (skb == NULL)			break;		/* 		 * If this is the last packet, turn off the TIM bit.		 *		 * Set the M_PWR_SAV bit on skb to allow encap to test for		 * adding MORE_DATA bit to wh.		 *		 * The 802.11 MAC Spec says we should only set MORE_DATA for 		 * unicast packets when the STA is in PS mode (7.1.3.1.8);		 * which it isn't.		 */		// M_PWR_SAV_SET(skb);#ifdef ATH_SUPERG_XR		/*		 * if it is a XR vap, send the data to associated normal net		 * device. XR vap has a net device which is not registered with		 * OS. 		 */		if (vap->iv_xrvap && vap->iv_flags & IEEE80211_F_XR)			skb->dev = vap->iv_xrvap->iv_dev;		else			skb->dev = vap->iv_dev;		/* XXX? unnecessary */#endif				ieee80211_parent_queue_xmit(skb);	}	vap->iv_set_tim(ni, 0);}/* * Handle power-save state change in station mode. */voidieee80211_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);			for (;;) {				struct sk_buff *skb;				IEEE80211_NODE_SAVEQ_LOCK(ni);				skb = __skb_dequeue(&ni->ni_savedq);				IEEE80211_NODE_SAVEQ_UNLOCK(ni);				if (skb == NULL)					break;				ieee80211_parent_queue_xmit(skb);			}		}	} else {		ni->ni_flags |= IEEE80211_NODE_PWR_MGT;		ieee80211_send_nulldata(ieee80211_ref_node(ni));	}}