C++ IEEE80211_LOCK函数代码示例

/*
 * 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;
}

/*
 * Start a scan unless one is already going.
 */
int
ieee80211_start_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;
	const struct ieee80211_scanner *scan;
	int result;

	scan = ieee80211_scanner_get(vap->iv_opmode);
	if (scan == NULL) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
		    "%s: no scanner support for %s mode\n",
		    __func__, ieee80211_opmode_name[vap->iv_opmode]);
		/* XXX stat */
		return 0;
	}

	IEEE80211_LOCK(ic);
	result = start_scan_locked(scan, vap, flags, duration,
	    mindwell, maxdwell, nssid, ssids);
	IEEE80211_UNLOCK(ic);

	return result;
}

void
ieee80211_scan_detach(struct ieee80211com *ic)
{
	struct ieee80211_scan_state *ss = ic->ic_scan;

	if (ss != NULL) {
		IEEE80211_LOCK(ic);
		SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT;
		scan_signal(ss);
		IEEE80211_UNLOCK(ic);
		ieee80211_draintask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
		callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer);
		KASSERT((ic->ic_flags & IEEE80211_F_SCAN) == 0,
		    ("scan still running"));
		if (ss->ss_ops != NULL) {
			ss->ss_ops->scan_detach(ss);
			ss->ss_ops = NULL;
		}
		ic->ic_scan = NULL;
		free(SCAN_PRIVATE(ss), M_80211_SCAN);
	}
	

#if defined(__ANTARES__)
	ieee80211_scan_sta_uninit();
#endif
}

static void
cancel_scan(struct ieee80211vap *vap, int any, const char *func)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	IEEE80211_LOCK(ic);
	if ((ic->ic_flags & IEEE80211_F_SCAN) &&
	    (any || ss->ss_vap == vap) &&
	    (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
		    "%s: cancel %s scan\n", func,
		    ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
			"active" : "passive");

		/* clear bg scan NOPICK */
		ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
		/* mark cancel request and wake up the scan task */
		scan_signal_locked(ss, ISCAN_CANCEL);
	} else {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
		    "%s: called; F_SCAN=%d, vap=%s, CANCEL=%d\n",
			func,
			!! (ic->ic_flags & IEEE80211_F_SCAN),
			(ss->ss_vap == vap ? "match" : "nomatch"),
			!! (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL));
	}
	IEEE80211_UNLOCK(ic);
}

/* 
 * Tear down vap state and reclaim the ifnet.
 * The driver is assumed to have prepared for
 * this; e.g. by turning off interrupts for the
 * underlying device.
 */
void
ieee80211_vap_detach(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ifnet *ifp = vap->iv_ifp;

	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s parent %s\n",
	    __func__, ieee80211_opmode_name[vap->iv_opmode],
	    ic->ic_ifp->if_xname);

	/* NB: bpfdetach is called by ether_ifdetach and claims all taps */
	ether_ifdetach(ifp);

	ieee80211_stop(vap);

	/*
	 * Flush any deferred vap tasks.
	 */
	ieee80211_draintask(ic, &vap->iv_nstate_task);
	ieee80211_draintask(ic, &vap->iv_swbmiss_task);

	/* XXX band-aid until ifnet handles this for us */
	taskqueue_drain(taskqueue_swi, &ifp->if_linktask);

	IEEE80211_LOCK(ic);
	KASSERT(vap->iv_state == IEEE80211_S_INIT , ("vap still running"));
	TAILQ_REMOVE(&ic->ic_vaps, vap, iv_next);
	ieee80211_syncflag_locked(ic, IEEE80211_F_WME);
#ifdef IEEE80211_SUPPORT_SUPERG
	ieee80211_syncflag_locked(ic, IEEE80211_F_TURBOP);
#endif
	ieee80211_syncflag_locked(ic, IEEE80211_F_PCF);
	ieee80211_syncflag_locked(ic, IEEE80211_F_BURST);
	ieee80211_syncflag_ht_locked(ic, IEEE80211_FHT_HT);
	ieee80211_syncflag_ht_locked(ic, IEEE80211_FHT_USEHT40);
	/* NB: this handles the bpfdetach done below */
	ieee80211_syncflag_ext_locked(ic, IEEE80211_FEXT_BPF);
	ieee80211_syncifflag_locked(ic, IFF_PROMISC);
	ieee80211_syncifflag_locked(ic, IFF_ALLMULTI);
	IEEE80211_UNLOCK(ic);

	ifmedia_removeall(&vap->iv_media);

	ieee80211_radiotap_vdetach(vap);
	ieee80211_regdomain_vdetach(vap);
	ieee80211_scan_vdetach(vap);
#ifdef IEEE80211_SUPPORT_SUPERG
	ieee80211_superg_vdetach(vap);
#endif
	ieee80211_ht_vdetach(vap);
	/* NB: must be before ieee80211_node_vdetach */
	ieee80211_proto_vdetach(vap);
	ieee80211_crypto_vdetach(vap);
	ieee80211_power_vdetach(vap);
	ieee80211_node_vdetach(vap);
	ieee80211_sysctl_vdetach(vap);

	if_free(ifp);
}

/*
 * Activate a vap.  State should have been prepared with a
 * call to ieee80211_vap_setup and by the driver.  On return
 * from this call the vap is ready for use.
 */
int
ieee80211_vap_attach(struct ieee80211vap *vap,
	ifm_change_cb_t media_change, ifm_stat_cb_t media_stat)
{
	struct ifnet *ifp = vap->iv_ifp;
	struct ieee80211com *ic = vap->iv_ic;
	struct ifmediareq imr;
	int maxrate;

	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
	    "%s: %s parent %s flags 0x%x flags_ext 0x%x\n",
	    __func__, ieee80211_opmode_name[vap->iv_opmode],
	    ic->ic_ifp->if_xname, vap->iv_flags, vap->iv_flags_ext);

	/*
	 * Do late attach work that cannot happen until after
	 * the driver has had a chance to override defaults.
	 */
	ieee80211_node_latevattach(vap);
	ieee80211_power_latevattach(vap);

	maxrate = ieee80211_media_setup(ic, &vap->iv_media, vap->iv_caps,
	    vap->iv_opmode == IEEE80211_M_STA, media_change, media_stat);
	ieee80211_media_status(ifp, &imr);
	/* NB: strip explicit mode; we're actually in autoselect */
	ifmedia_set(&vap->iv_media,
	    imr.ifm_active &~ (IFM_MMASK | IFM_IEEE80211_TURBO));
	if (maxrate)
		ifp->if_baudrate = IF_Mbps(maxrate);

	ether_ifattach(ifp, vap->iv_myaddr);
	if (vap->iv_opmode == IEEE80211_M_MONITOR) {
		/* NB: disallow transmit */
		ifp->if_transmit = null_transmit;
		ifp->if_output = null_output;
	} else {
		/* hook output method setup by ether_ifattach */
		vap->iv_output = ifp->if_output;
		ifp->if_output = ieee80211_output;
	}
	/* NB: if_mtu set by ether_ifattach to ETHERMTU */

	IEEE80211_LOCK(ic);
	TAILQ_INSERT_TAIL(&ic->ic_vaps, vap, iv_next);
	ieee80211_syncflag_locked(ic, IEEE80211_F_WME);
#ifdef IEEE80211_SUPPORT_SUPERG
	ieee80211_syncflag_locked(ic, IEEE80211_F_TURBOP);
#endif
	ieee80211_syncflag_locked(ic, IEEE80211_F_PCF);
	ieee80211_syncflag_locked(ic, IEEE80211_F_BURST);
	ieee80211_syncflag_ht_locked(ic, IEEE80211_FHT_HT);
	ieee80211_syncflag_ht_locked(ic, IEEE80211_FHT_USEHT40);
	ieee80211_syncifflag_locked(ic, IFF_PROMISC);
	ieee80211_syncifflag_locked(ic, IFF_ALLMULTI);
	IEEE80211_UNLOCK(ic);

	return 1;
}

/*
 * Handle mindwell requirements completed; initiate a channel
 * change to the next channel asap.
 */
static void
scan_mindwell(struct ieee80211_scan_state *ss)
{
	struct ieee80211com *ic = ss->ss_ic;

	IEEE80211_LOCK(ic);
	scan_signal(ss);
	IEEE80211_UNLOCK(ic);
}

/**
 * This function provides control to simulate Radar event
 *
 * @param 
 *  SYSCTL_HANDLER_ARGS Standard arguments of the Linux sysctl handler 
 *
 * @returns 
 *  0 on success, or corresponding negative error code on failure
 */
static int
ieee80211_sysctl_radar(SYSCTL_HANDLER_ARGS)
{
	struct ieee80211com *ic  = ctl->extra1;
	
	IEEE80211_LOCK(ic);
	ieee80211_dfs_notify_radar(ic, ic->ic_curchan);
	IEEE80211_UNLOCK(ic); 
	return 0;
}

static void
scan_signal(struct ieee80211_scan_state *ss, int iflags)
{
	struct ieee80211com *ic = ss->ss_ic;

	IEEE80211_UNLOCK_ASSERT(ic);

	IEEE80211_LOCK(ic);
	scan_signal_locked(ss, iflags);
	IEEE80211_UNLOCK(ic);
}

/*
 * Public access to scan_next for drivers that manage
 * scanning themselves (e.g. for firmware-based devices).
 */
void
ieee80211_scan_next(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss = ic->ic_scan;

	/* wake up the scan task */
	IEEE80211_LOCK(ic);
	scan_signal(ss);
	IEEE80211_UNLOCK(ic);
}

/*
 * Public access to scan_next for drivers that are not able to scan single
 * channels (e.g. for firmware-based devices).
 */
void
ieee80211_scan_done(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ieee80211_scan_state *ss;

	IEEE80211_LOCK(ic);
	ss = ic->ic_scan;
	ss->ss_next = ss->ss_last; /* all channels are complete */
	scan_signal(ss);
	IEEE80211_UNLOCK(ic);
}

/*
 * Scan curchan.  If this is an active scan and the channel
 * is not marked passive then send probe request frame(s).
 * Arrange for the channel change after maxdwell ticks.
 */
static void
scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
{
	struct ieee80211vap *vap  = ss->ss_vap;

	IEEE80211_LOCK(vap->iv_ic);
	if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
		ieee80211_probe_curchan(vap, 0);
	callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
	    maxdwell, scan_signal, ss);
	IEEE80211_UNLOCK(vap->iv_ic);
}

/*
 * Check the scan cache for an ap/channel to use; if that
 * fails then kick off a new scan.
 */
int
ieee80211_check_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;
	const struct ieee80211_scanner *scan;
	int result;

	scan = ieee80211_scanner_get(vap->iv_opmode);
	if (scan == NULL) {
		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
		    "%s: no scanner support for %s mode\n",
		    __func__, vap->iv_opmode);
		/* XXX stat */
		return 0;
	}

	/*
	 * Check if there's a list of scan candidates already.
	 * XXX want more than the ap we're currently associated with
	 */

	IEEE80211_LOCK(ic);
	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
	    "%s: %s scan, %s%s%s%s%s\n"
	    , __func__
	    , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
	    , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
	    , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
	    , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
	    , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
	    , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
	);

	if (ss->ss_ops != scan) {
		/* XXX re-use cache contents? e.g. adhoc<->sta */
		flags |= IEEE80211_SCAN_FLUSH;
	}

	/*
	 * XXX TODO: separate things out a bit better.
	 */
	ieee80211_scan_update_locked(vap, scan);

	result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
	    mindwell, maxdwell, nssid, ssids);

	IEEE80211_UNLOCK(ic);

	return (result);
}

void
ieee80211_syncflag_ext(struct ieee80211vap *vap, int flag)
{
	struct ieee80211com *ic = vap->iv_ic;

	IEEE80211_LOCK(ic);
	if (flag < 0) {
		flag = -flag;
		vap->iv_flags_ext &= ~flag;
	} else
		vap->iv_flags_ext |= flag;
	ieee80211_syncflag_ext_locked(ic, flag);
	IEEE80211_UNLOCK(ic);
}

static int
ieee80211_sysctl_radar(SYSCTL_HANDLER_ARGS)
{
	struct ieee80211com *ic = arg1;
	int t = 0, error;

	error = sysctl_handle_int(oidp, &t, 0, req);
	if (error || !req->newptr)
		return error;
	IEEE80211_LOCK(ic);
	ieee80211_dfs_notify_radar(ic, ic->ic_curchan);
	IEEE80211_UNLOCK(ic);
	return 0;
}