C++ IEEE80211_LOCK_ASSERT函数代码示例

static void
tdma_beacon_miss(struct ieee80211vap *vap)
{
	struct ieee80211_tdma_state *ts = vap->iv_tdma;

	IEEE80211_LOCK_ASSERT(vap->iv_ic);

	KASSERT((vap->iv_ic->ic_flags & IEEE80211_F_SCAN) == 0, ("scanning"));
	KASSERT(vap->iv_state == IEEE80211_S_RUN,
	    ("wrong state %d", vap->iv_state));

	IEEE80211_DPRINTF(vap,
		IEEE80211_MSG_STATE | IEEE80211_MSG_TDMA | IEEE80211_MSG_DEBUG,
		"beacon miss, mode %u state %s\n",
		vap->iv_opmode, ieee80211_state_name[vap->iv_state]);

	callout_stop(&vap->iv_swbmiss);

	if (ts->tdma_peer != NULL) {	/* XXX? can this be null? */
		ieee80211_notify_node_leave(vap->iv_bss);
		ts->tdma_peer = NULL;
		/*
		 * Treat beacon miss like an associate failure wrt the
		 * scan policy; this forces the entry in the scan cache
		 * to be ignored after several tries.
		 */
		ieee80211_scan_assoc_fail(vap, vap->iv_bss->ni_macaddr,
		    IEEE80211_STATUS_TIMEOUT);
	}
#if 0
	ts->tdma_inuse = 0;		/* clear slot usage */
#endif
	ieee80211_new_state(vap, IEEE80211_S_SCAN, 0);
}

/*
 * IEEE80211_M_MONITOR vap state machine handler.
 */
static int
monitor_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
{
	struct ieee80211com *ic = vap->iv_ic;
	enum ieee80211_state ostate;

	IEEE80211_LOCK_ASSERT(ic);

	ostate = vap->iv_state;
	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
	    __func__, ieee80211_state_name[ostate],
	    ieee80211_state_name[nstate], arg);
	vap->iv_state = nstate;			/* state transition */
	if (nstate == IEEE80211_S_RUN) {
		switch (ostate) {
		case IEEE80211_S_INIT:
			ieee80211_create_ibss(vap, ic->ic_curchan);
			break;
		default:
			break;
		}
		/*
		 * NB: this shouldn't be here but many people use
		 * monitor mode for raw packets; once we switch
		 * them over to adhoc demo mode remove this.
		 */
		ieee80211_node_authorize(vap->iv_bss);
	}
	return 0;
}

static void
scan_signal(void *arg)
{
	struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;

	IEEE80211_LOCK_ASSERT(ss->ss_ic);

	cv_signal(&SCAN_PRIVATE(ss)->ss_scan_cv);
}

/*
 * Manually stop a scan that is currently running.
 * Provided for drivers that are not able to scan single channels
 * (e.g. for firmware-based devices).
 */
static void
ieee80211_swscan_scan_done(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK_ASSERT(ic);

	scan_signal_locked(ss, 0);
}

static void
ieee80211_swscan_vdetach(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK_ASSERT(ic);

	if (ss != NULL && ss->ss_vap == vap &&
	    (ic->ic_flags & IEEE80211_F_SCAN))
		scan_signal_locked(ss, ISCAN_ABORT);
}

/*
 * Check the scan cache for an ap/channel to use; if that
 * fails then kick off a new scan.
 *
 * Called with the comlock held.
 *
 * XXX TODO: split out!
 */
static int
ieee80211_swscan_check_scan(const struct ieee80211_scanner *scan,
    struct ieee80211vap *vap, int flags,
    u_int duration, u_int mindwell, u_int maxdwell,
    u_int nssid, const struct ieee80211_scan_ssid ssids[])
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;
	int result;

	IEEE80211_LOCK_ASSERT(ic);

	if (ss->ss_ops != NULL) {
		/* XXX verify ss_ops matches vap->iv_opmode */
		if ((flags & IEEE80211_SCAN_NOSSID) == 0) {
			/*
			 * Update the ssid list and mark flags so if
			 * we call start_scan it doesn't duplicate work.
			 */
			ieee80211_scan_copy_ssid(vap, ss, nssid, ssids);
			flags |= IEEE80211_SCAN_NOSSID;
		}
		if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 &&
		    (flags & IEEE80211_SCAN_FLUSH) == 0 &&
		    ieee80211_time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
			/*
			 * We're not currently scanning and the cache is
			 * deemed hot enough to consult.  Lock out others
			 * by marking IEEE80211_F_SCAN while we decide if
			 * something is already in the scan cache we can
			 * use.  Also discard any frames that might come
			 * in while temporarily marked as scanning.
			 */
			SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
			ic->ic_flags |= IEEE80211_F_SCAN;

			/* NB: need to use supplied flags in check */
			ss->ss_flags = flags & 0xff;
			result = ss->ss_ops->scan_end(ss, vap);

			ic->ic_flags &= ~IEEE80211_F_SCAN;
			SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD;
			if (result) {
				ieee80211_notify_scan_done(vap);
				return 1;
			}
		}
	}
	result = ieee80211_swscan_start_scan_locked(scan, vap, flags, duration,
	    mindwell, maxdwell, nssid, ssids);

	return result;
}

static void
ieee80211_swscan_set_scan_duration(struct ieee80211vap *vap, u_int duration)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK_ASSERT(ic);

	/* NB: flush frames rx'd before 1st channel change */
	SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
	SCAN_PRIVATE(ss)->ss_duration = duration;
}

/*
 * Initiate the CAC timer.  The driver is responsible
 * for setting up the hardware to scan for radar on the
 * channnel, we just handle timing things out.
 */
void
ieee80211_dfs_cac_start(struct ieee80211vap *vap)
{
    struct ieee80211com *ic = vap->iv_ic;
    struct ieee80211_dfs_state *dfs = &ic->ic_dfs;

    IEEE80211_LOCK_ASSERT(ic);

    callout_reset(&dfs->cac_timer, CAC_TIMEOUT, cac_timeout, vap);
    if_printf(vap->iv_ifp, "start %d second CAC timer on channel %u (%u MHz)\n",
              ticks_to_secs(CAC_TIMEOUT),
              ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq);
    ieee80211_notify_cac(ic, ic->ic_curchan, IEEE80211_NOTIFY_CAC_START);
}

static void
cac_timeout(void *arg)
{
    struct ieee80211vap *vap = arg;
    struct ieee80211com *ic = vap->iv_ic;
    struct ieee80211_dfs_state *dfs = &ic->ic_dfs;
    int i;

    IEEE80211_LOCK_ASSERT(ic);

    if (vap->iv_state != IEEE80211_S_CAC)	/* NB: just in case */
        return;
    /*
     * When radar is detected during a CAC we are woken
     * up prematurely to switch to a new channel.
     * Check the channel to decide how to act.
     */
    if (IEEE80211_IS_CHAN_RADAR(ic->ic_curchan)) {
        ieee80211_notify_cac(ic, ic->ic_curchan,
                             IEEE80211_NOTIFY_CAC_RADAR);

        if_printf(vap->iv_ifp,
                  "CAC timer on channel %u (%u MHz) stopped due to radar\n",
                  ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq);

        /* XXX clobbers any existing desired channel */
        /* NB: dfs->newchan may be NULL, that's ok */
        vap->iv_des_chan = dfs->newchan;
        /* XXX recursive lock need ieee80211_new_state_locked */
        ieee80211_new_state(vap, IEEE80211_S_SCAN, 0);
    } else {
        if_printf(vap->iv_ifp,
                  "CAC timer on channel %u (%u MHz) expired; "
                  "no radar detected\n",
                  ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq);
        /*
         * Mark all channels with the current frequency
         * as having completed CAC; this keeps us from
         * doing it again until we change channels.
         */
        for (i = 0; i < ic->ic_nchans; i++) {
            struct ieee80211_channel *c = &ic->ic_channels[i];
            if (c->ic_freq == ic->ic_curchan->ic_freq)
                c->ic_state |= IEEE80211_CHANSTATE_CACDONE;
        }
        ieee80211_notify_cac(ic, ic->ic_curchan,
                             IEEE80211_NOTIFY_CAC_EXPIRE);
        ieee80211_cac_completeswitch(vap);
    }
}

static void
scan_signal_locked(struct ieee80211_scan_state *ss, int iflags)
{
	struct scan_state *ss_priv = SCAN_PRIVATE(ss);
	struct timeout_task *scan_task = &ss_priv->ss_scan_curchan;
	struct ieee80211com *ic = ss->ss_ic;

	IEEE80211_LOCK_ASSERT(ic);

	ss_priv->ss_iflags |= iflags;
	if (ss_priv->ss_iflags & ISCAN_RUNNING) {
		if (taskqueue_cancel_timeout(ic->ic_tq, scan_task, NULL) == 0)
			taskqueue_enqueue_timeout(ic->ic_tq, scan_task, 0);
	}
}

/*
 * Clear the CAC timer.
 */
void
ieee80211_dfs_cac_stop(struct ieee80211vap *vap)
{
    struct ieee80211com *ic = vap->iv_ic;
    struct ieee80211_dfs_state *dfs = &ic->ic_dfs;

    IEEE80211_LOCK_ASSERT(ic);

    /* NB: racey but not important */
    if (callout_pending(&dfs->cac_timer)) {
        if_printf(vap->iv_ifp, "stop CAC timer on channel %u (%u MHz)\n",
                  ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq);
        ieee80211_notify_cac(ic, ic->ic_curchan,
                             IEEE80211_NOTIFY_CAC_STOP);
    }
    callout_stop(&dfs->cac_timer);
}

/*
 * Update common scanner state to reflect the current
 * operating mode.  This is called when the state machine
 * is transitioned to RUN state w/o scanning--e.g. when
 * operating in monitor mode.  The purpose of this is to
 * ensure later callbacks find ss_ops set to properly
 * reflect current operating mode.
 */
static void
scan_update_locked(struct ieee80211vap *vap,
	const struct ieee80211_scanner *scan)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK_ASSERT(ic);

#ifdef IEEE80211_DEBUG
	if (ss->ss_vap != vap || ss->ss_ops != scan) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
		    "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
		    __func__,
		    ss->ss_vap != NULL ?
			ss->ss_vap->iv_ifp->if_xname : "none",
		    ss->ss_vap != NULL ?
			ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
		    vap->iv_ifp->if_xname,
		    ieee80211_opmode_name[vap->iv_opmode]);
	}
#endif
	ss->ss_vap = vap;
	if (ss->ss_ops != scan) {
		/*
		 * Switch scanners; detach old, attach new.  Special
		 * case where a single scan module implements multiple
		 * policies by using different scan ops but a common
		 * core.  We assume if the old and new attach methods
		 * are identical then it's ok to just change ss_ops
		 * and not flush the internal state of the module.
		 */
		if (scan == NULL || ss->ss_ops == NULL ||
		    ss->ss_ops->scan_attach != scan->scan_attach) {
			if (ss->ss_ops != NULL)
				ss->ss_ops->scan_detach(ss);
			if (scan != NULL && !scan->scan_attach(ss)) {
				/* XXX attach failure */
				/* XXX stat+msg */
				scan = NULL;
			}
		}
		ss->ss_ops = scan;
	}
}

/*
 * Synchronize flags_ext bit state in the com structure
 * according to the state of all vap's.  This is used,
 * for example, to handle state changes via ioctls.
 */
static void
ieee80211_syncflag_ext_locked(struct ieee80211com *ic, int flag)
{
	struct ieee80211vap *vap;
	int bit;

	IEEE80211_LOCK_ASSERT(ic);

	bit = 0;
	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next)
		if (vap->iv_flags_ext & flag) {
			bit = 1;
			break;
		}
	if (bit)
		ic->ic_flags_ext |= flag;
	else
		ic->ic_flags_ext &= ~flag;
}

/*
 * Check the scan cache for an ap/channel to use; if that
 * fails then kick off a new scan.
 */
struct ieee80211_channel *
ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
{
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK_ASSERT(ic);

	if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
		/* XXX printf? */
		return NULL;
	}
	if (ss->ss_ops->scan_pickchan == NULL) {
		IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
		    "%s: scan module does not support picking a channel, "
		    "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
		return NULL;
	}
	return ss->ss_ops->scan_pickchan(ss, flags);
}

/*
 * Synchronize flag bit state in the parent ifnet structure
 * according to the state of all vap ifnet's.  This is used,
 * for example, to handle IFF_PROMISC and IFF_ALLMULTI.
 */
void
ieee80211_syncifflag_locked(struct ieee80211com *ic, int flag)
{
	struct ifnet *ifp = ic->ic_ifp;
	struct ieee80211vap *vap;
	int bit, oflags;

	IEEE80211_LOCK_ASSERT(ic);

	bit = 0;
	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next)
		if (vap->iv_ifp->if_flags & flag) {
			/*
			 * XXX the bridge sets PROMISC but we don't want to
			 * enable it on the device, discard here so all the
			 * drivers don't need to special-case it
			 */
			if (flag == IFF_PROMISC &&
			    !(vap->iv_opmode == IEEE80211_M_MONITOR ||
			      (vap->iv_opmode == IEEE80211_M_AHDEMO &&
			       (vap->iv_caps & IEEE80211_C_TDMA) == 0)))
				continue;
			bit = 1;
			break;
		}
	oflags = ifp->if_flags;
	if (bit)
		ifp->if_flags |= flag;
	else
		ifp->if_flags &= ~flag;
	if ((ifp->if_flags ^ oflags) & flag) {
		/* XXX should we return 1/0 and let caller do this? */
		if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
			if (flag == IFF_PROMISC)
				ieee80211_runtask(ic, &ic->ic_promisc_task);
			else if (flag == IFF_ALLMULTI)
				ieee80211_runtask(ic, &ic->ic_mcast_task);
		}
	}
}