Clarify/fix handling of the current channel:

o add ic_curchan and use it uniformly for specifying the current
  channel instead of overloading ic->ic_bss->ni_chan (or in some
  drivers ic_ibss_chan)
o add ieee80211_scanparams structure to encapsulate scanning-related
  state captured for rx frames
o move rx beacon+probe response frame handling into separate routines
o change beacon+probe response handling to treat the scan table
  more like a scan cache--look for an existing entry before adding
  a new one; this combined with ic_curchan use corrects handling of
  stations that were previously found at a different channel
o move adhoc neighbor discovery by beacon+probe response frames to
  a new ieee80211_add_neighbor routine

Reviewed by:	avatar
Tested by:	avatar, Michal Mertl
MFC after:	2 weeks

5 files changed, 23 insertions, 23 deletions

diff --git a/sys/dev/ath/if_ath.c b/sys/dev/ath/if_ath.c
index afd9d61..05cad26 100644
--- a/sys/dev/ath/if_ath.c
+++ b/sys/dev/ath/if_ath.c
@@ -844,7 +844,6 @@ ath_init(void *arg)
 	struct ath_softc *sc = (struct ath_softc *) arg;
 	struct ieee80211com *ic = &sc->sc_ic;
 	struct ifnet *ifp = sc->sc_ifp;
-	struct ieee80211_node *ni;
 	struct ath_hal *ah = sc->sc_ah;
 	HAL_STATUS status;
 
@@ -865,8 +864,8 @@ ath_init(void *arg)
 	 * be followed by initialization of the appropriate bits
 	 * and then setup of the interrupt mask.
 	 */
-	sc->sc_curchan.channel = ic->ic_ibss_chan->ic_freq;
-	sc->sc_curchan.channelFlags = ath_chan2flags(ic, ic->ic_ibss_chan);
+	sc->sc_curchan.channel = ic->ic_curchan->ic_freq;
+	sc->sc_curchan.channelFlags = ath_chan2flags(ic, ic->ic_curchan);
 	if (!ath_hal_reset(ah, ic->ic_opmode, &sc->sc_curchan, AH_FALSE, &status)) {
 		if_printf(ifp, "unable to reset hardware; hal status %u\n",
 			status);
@@ -918,9 +917,7 @@ ath_init(void *arg)
 	 * to kick the 802.11 state machine as it's likely to
 	 * immediately call back to us to send mgmt frames.
 	 */
-	ni = ic->ic_bss;
-	ni->ni_chan = ic->ic_ibss_chan;
-	ath_chan_change(sc, ni->ni_chan);
+	ath_chan_change(sc, ic->ic_curchan);
 	if (ic->ic_opmode != IEEE80211_M_MONITOR) {
 		if (ic->ic_roaming != IEEE80211_ROAMING_MANUAL)
 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
@@ -1022,7 +1019,7 @@ ath_reset(struct ifnet *ifp)
 	 * Convert to a HAL channel description with the flags
 	 * constrained to reflect the current operating mode.
 	 */
-	c = ic->ic_ibss_chan;
+	c = ic->ic_curchan;
 	sc->sc_curchan.channel = c->ic_freq;
 	sc->sc_curchan.channelFlags = ath_chan2flags(ic, c);
 
@@ -4114,7 +4111,7 @@ ath_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 		goto done;
 	}
 	ni = ic->ic_bss;
-	error = ath_chan_set(sc, ni->ni_chan);
+	error = ath_chan_set(sc, ic->ic_curchan);
 	if (error != 0)
 		goto bad;
 	rfilt = ath_calcrxfilter(sc, nstate);
@@ -4153,7 +4150,7 @@ ath_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 			 , ni->ni_intval
 			 , ether_sprintf(ni->ni_bssid)
 			 , ni->ni_capinfo
-			 , ieee80211_chan2ieee(ic, ni->ni_chan));
+			 , ieee80211_chan2ieee(ic, ic->ic_curchan));
 
 		switch (ic->ic_opmode) {
 		case IEEE80211_M_HOSTAP:
diff --git a/sys/dev/ipw/if_ipw.c b/sys/dev/ipw/if_ipw.c
index 88afe1c..2d850a9 100644
--- a/sys/dev/ipw/if_ipw.c
+++ b/sys/dev/ipw/if_ipw.c
@@ -1002,7 +1002,7 @@ ipw_fix_channel(struct ieee80211com *ic, struct mbuf *m)
 #if IEEE80211_CHAN_MAX < 255
 		if (frm[2] <= IEEE80211_CHAN_MAX)
 #endif
-			ic->ic_bss->ni_chan = &ic->ic_channels[frm[2]];
+			ic->ic_curchan = &ic->ic_channels[frm[2]];
 
 		frm += frm[1] + 2;
 	}
diff --git a/sys/dev/ral/if_ral.c b/sys/dev/ral/if_ral.c
index 716bde4..1b275e9 100644
--- a/sys/dev/ral/if_ral.c
+++ b/sys/dev/ral/if_ral.c
@@ -990,21 +990,21 @@ ral_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 		break;
 
 	case IEEE80211_S_SCAN:
-		ral_set_chan(sc, ic->ic_bss->ni_chan);
+		ral_set_chan(sc, ic->ic_curchan);
 		callout_reset(&sc->scan_ch, (sc->dwelltime * hz) / 1000,
 		    ral_next_scan, sc);
 		break;
 
 	case IEEE80211_S_AUTH:
-		ral_set_chan(sc, ic->ic_bss->ni_chan);
+		ral_set_chan(sc, ic->ic_curchan);
 		break;
 
 	case IEEE80211_S_ASSOC:
-		ral_set_chan(sc, ic->ic_bss->ni_chan);
+		ral_set_chan(sc, ic->ic_curchan);
 		break;
 
 	case IEEE80211_S_RUN:
-		ral_set_chan(sc, ic->ic_bss->ni_chan);
+		ral_set_chan(sc, ic->ic_curchan);
 
 		if (ic->ic_opmode != IEEE80211_M_MONITOR)
 			ral_set_bssid(sc, ic->ic_bss->ni_bssid);
@@ -1768,7 +1768,7 @@ ral_tx_mgt(struct ral_softc *sc, struct mbuf *m0, struct ieee80211_node *ni)
 	desc = &sc->prioq.desc[sc->prioq.cur];
 	data = &sc->prioq.data[sc->prioq.cur];
 
-	rate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 4;
+	rate = IEEE80211_IS_CHAN_5GHZ(ic->ic_curchan) ? 12 : 4;
 
 	error = bus_dmamap_load_mbuf_sg(sc->prioq.data_dmat, data->map, m0,
 	    segs, &nsegs, 0);
@@ -1910,7 +1910,7 @@ ral_tx_data(struct ral_softc *sc, struct mbuf *m0, struct ieee80211_node *ni)
 		uint16_t dur;
 		int rtsrate, ackrate;
 
-		rtsrate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 4;
+		rtsrate = IEEE80211_IS_CHAN_5GHZ(ic->ic_curchan) ? 12 : 4;
 		ackrate = ral_ack_rate(rate);
 
 		dur = ral_txtime(m0->m_pkthdr.len + 4, rate, ic->ic_flags) +
@@ -2739,7 +2739,8 @@ ral_init(void *priv)
 
 	/* set default BSS channel */
 	ic->ic_bss->ni_chan = ic->ic_ibss_chan;
-	ral_set_chan(sc, ic->ic_bss->ni_chan);
+	ic->ic_curchan = ic->ic_ibss_chan;
+	ral_set_chan(sc, ic->ic_curchan);
 
 	/* kick Rx */
 	tmp = RAL_DROP_PHY_ERROR | RAL_DROP_CRC_ERROR;
diff --git a/sys/dev/usb/if_ural.c b/sys/dev/usb/if_ural.c
index 0083652..7deb1bc 100644
--- a/sys/dev/usb/if_ural.c
+++ b/sys/dev/usb/if_ural.c
@@ -722,20 +722,20 @@ ural_task(void *arg)
 		break;
 
 	case IEEE80211_S_SCAN:
-		ural_set_chan(sc, ic->ic_bss->ni_chan);
+		ural_set_chan(sc, ic->ic_curchan);
 		callout_reset(&sc->scan_ch, hz / 5, ural_next_scan, sc);
 		break;
 
 	case IEEE80211_S_AUTH:
-		ural_set_chan(sc, ic->ic_bss->ni_chan);
+		ural_set_chan(sc, ic->ic_curchan);
 		break;
 
 	case IEEE80211_S_ASSOC:
-		ural_set_chan(sc, ic->ic_bss->ni_chan);
+		ural_set_chan(sc, ic->ic_curchan);
 		break;
 
 	case IEEE80211_S_RUN:
-		ural_set_chan(sc, ic->ic_bss->ni_chan);
+		ural_set_chan(sc, ic->ic_curchan);
 
 		if (ic->ic_opmode != IEEE80211_M_MONITOR)
 			ural_set_bssid(sc, ic->ic_bss->ni_bssid);
@@ -1125,7 +1125,7 @@ ural_tx_mgt(struct ural_softc *sc, struct mbuf *m0, struct ieee80211_node *ni)
 	data = &sc->tx_data[0];
 	desc = (struct ural_tx_desc *)data->buf;
 
-	rate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 4;
+	rate = IEEE80211_IS_CHAN_5GHZ(ic->ic_curchan) ? 12 : 4;
 
 	if (sc->sc_drvbpf != NULL) {
 		struct ural_tx_radiotap_header *tap = &sc->sc_txtap;
@@ -1956,7 +1956,8 @@ ural_init(void *priv)
 
 	/* set default BSS channel */
 	ic->ic_bss->ni_chan = ic->ic_ibss_chan;
-	ural_set_chan(sc, ic->ic_bss->ni_chan);
+	ic->ic_curchan = ic->ic_ibss_chan;
+	ural_set_chan(sc, ic->ic_curchan);
 
 	/* clear statistic registers (STA_CSR0 to STA_CSR10) */
 	ural_read_multi(sc, RAL_STA_CSR0, sta, sizeof sta);
diff --git a/sys/dev/wi/if_wi.c b/sys/dev/wi/if_wi.c
index 4de137c..fc9ab4d 100644
--- a/sys/dev/wi/if_wi.c
+++ b/sys/dev/wi/if_wi.c
@@ -2736,6 +2736,7 @@ wi_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 		wi_read_rid(sc, WI_RID_CURRENT_CHAN, &val, &buflen);
 		/* XXX validate channel */
 		ni->ni_chan = &ic->ic_channels[le16toh(val)];
+		ic->ic_curchan = ni->ni_chan;
 		ic->ic_ibss_chan = ni->ni_chan;
 #if NBPFILTER > 0
 		sc->sc_tx_th.wt_chan_freq = sc->sc_rx_th.wr_chan_freq =