Replay r286410. Change KPI of how device drivers that provide wireless

connectivity interact with the net80211 stack.

Historical background: originally wireless devices created an interface,
just like Ethernet devices do. Name of an interface matched the name of
the driver that created. Later, wlan(4) layer was introduced, and the
wlanX interfaces become the actual interface, leaving original ones as
"a parent interface" of wlanX. Kernelwise, the KPI between net80211 layer
and a driver became a mix of methods that pass a pointer to struct ifnet
as identifier and methods that pass pointer to struct ieee80211com. From
user point of view, the parent interface just hangs on in the ifconfig
list, and user can't do anything useful with it.

Now, the struct ifnet goes away. The struct ieee80211com is the only
KPI between a device driver and net80211. Details:

- The struct ieee80211com is embedded into drivers softc.
- Packets are sent via new ic_transmit method, which is very much like
  the previous if_transmit.
- Bringing parent up/down is done via new ic_parent method, which notifies
  driver about any changes: number of wlan(4) interfaces, number of them
  in promisc or allmulti state.
- Device specific ioctls (if any) are received on new ic_ioctl method.
- Packets/errors accounting are done by the stack. In certain cases, when
  driver experiences errors and can not attribute them to any specific
  interface, driver updates ic_oerrors or ic_ierrors counters.

Details on interface configuration with new world order:
- A sequence of commands needed to bring up wireless DOESN"T change.
- /etc/rc.conf parameters DON'T change.
- List of devices that can be used to create wlan(4) interfaces is
  now provided by net.wlan.devices sysctl.

Most drivers in this change were converted by me, except of wpi(4),
that was done by Andriy Voskoboinyk. Big thanks to Kevin Lo for testing
changes to at least 8 drivers. Thanks to pluknet@, Oliver Hartmann,
Olivier Cochard, gjb@, mmoll@, op@ and lev@, who also participated in
testing.

Reviewed by:	adrian
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.

2 files changed, 29 insertions, 208 deletions

diff --git a/sys/dev/wtap/if_wtap.c b/sys/dev/wtap/if_wtap.c
index f6dbe77..526ce54 100644
--- a/sys/dev/wtap/if_wtap.c
+++ b/sys/dev/wtap/if_wtap.c
@@ -261,7 +261,7 @@ static int
 wtap_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
 {
 	struct ieee80211com *ic = vap->iv_ic;
-	struct wtap_softc *sc = ic->ic_ifp->if_softc;
+	struct wtap_softc *sc = ic->ic_softc;
 	struct wtap_vap *avp = WTAP_VAP(vap);
 	struct ieee80211_node *ni = NULL;
 	int error;
@@ -318,7 +318,7 @@ wtap_vap_create(struct ieee80211com *ic, const char name[IFNAMSIZ],
     const uint8_t bssid[IEEE80211_ADDR_LEN],
     const uint8_t mac[IEEE80211_ADDR_LEN])
 {
-	 struct wtap_softc *sc = ic->ic_ifp->if_softc;
+	 struct wtap_softc *sc = ic->ic_softc;
 	 struct ieee80211vap *vap;
 	 struct wtap_vap *avp;
 	 int error;
@@ -326,15 +326,13 @@ wtap_vap_create(struct ieee80211com *ic, const char name[IFNAMSIZ],
 
 	 DWTAP_PRINTF("%s\n", __func__);
 
-	avp = malloc(sizeof(struct wtap_vap), M_80211_VAP, M_NOWAIT | M_ZERO);
-	if (avp == NULL)
-		return (NULL);
+	avp = malloc(sizeof(struct wtap_vap), M_80211_VAP, M_WAITOK | M_ZERO);
 	avp->id = sc->id;
 	avp->av_md = sc->sc_md;
 	avp->av_bcinterval = msecs_to_ticks(BEACON_INTRERVAL + 100*sc->id);
 	vap = (struct ieee80211vap *) avp;
 	error = ieee80211_vap_setup(ic, vap, name, unit, IEEE80211_M_MBSS,
-	    flags | IEEE80211_CLONE_NOBEACONS, bssid, mac);
+	    flags | IEEE80211_CLONE_NOBEACONS, bssid);
 	if (error) {
 		free(avp, M_80211_VAP);
 		return (NULL);
@@ -351,9 +349,10 @@ wtap_vap_create(struct ieee80211com *ic, const char name[IFNAMSIZ],
 	vap->iv_bmiss = wtap_bmiss;
 
 	/* complete setup */
-	ieee80211_vap_attach(vap, wtap_media_change, ieee80211_media_status);
+	ieee80211_vap_attach(vap, wtap_media_change, ieee80211_media_status,
+	    mac);
 	avp->av_dev = make_dev(&wtap_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
-	    "%s", (const char *)ic->ic_ifp->if_xname);
+	    "%s", (const char *)sc->name);
 
 	/* TODO this is a hack to force it to choose the rate we want */
 	ni = ieee80211_ref_node(vap->iv_bss);
@@ -374,148 +373,16 @@ wtap_vap_delete(struct ieee80211vap *vap)
 	free((struct wtap_vap*) vap, M_80211_VAP);
 }
 
-/* NB: This function is not used.
- * I had the problem of the queue
- * being empty all the time.
- * Maybe I am setting the queue wrong?
- */
 static void
-wtap_start(struct ifnet *ifp)
+wtap_parent(struct ieee80211com *ic)
 {
-	struct ieee80211com *ic = ifp->if_l2com;
-	struct ifnet *icifp = ic->ic_ifp;
-	struct wtap_softc *sc = icifp->if_softc;
-	struct ieee80211_node *ni;
-	struct mbuf *m;
-
-	DWTAP_PRINTF("my_start, with id=%u\n", sc->id);
-
-	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || sc->up == 0)
-		return;
-	for (;;) {
-		if(IFQ_IS_EMPTY(&ifp->if_snd)){
-		    printf("queue empty, just trying to see "
-		        "if the other queue is empty\n");
-#if 0
-		    printf("queue for id=1, %u\n",
-		        IFQ_IS_EMPTY(&global_mscs[1]->ifp->if_snd));
-		    printf("queue for id=0, %u\n",
-		        IFQ_IS_EMPTY(&global_mscs[0]->ifp->if_snd));
-#endif
-		    break;
-		}
-		IFQ_DEQUEUE(&ifp->if_snd, m);
-		if (m == NULL) {
-			printf("error dequeueing from ifp->snd\n");
-			break;
-		}
-		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
-		/*
-		 * Check for fragmentation.  If this frame
-		 * has been broken up verify we have enough
-		 * buffers to send all the fragments so all
-		 * go out or none...
-		 */
-#if 0
-		STAILQ_INIT(&frags);
-#endif
-		if ((m->m_flags & M_FRAG)){
-			printf("dont support frags\n");
-			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
-			return;
-		}
-		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
-		if(wtap_raw_xmit(ni, m, NULL) < 0){
-			printf("error raw_xmiting\n");
-			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
-			return;
-		}
-	}
-}
-
-static int
-wtap_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
-{
-#if 0
-	DWTAP_PRINTF("%s\n", __func__);
-	uprintf("%s, command %lu\n", __func__, cmd);
-#endif
-#define	IS_RUNNING(ifp) \
-	((ifp->if_flags & IFF_UP) && (ifp->if_drv_flags & IFF_DRV_RUNNING))
-	struct ieee80211com *ic = ifp->if_l2com;
-	struct wtap_softc *sc = ifp->if_softc;
-	struct ifreq *ifr = (struct ifreq *)data;
-	int error = 0;
-
-	switch (cmd) {
-	case SIOCSIFFLAGS:
-		//printf("%s: %s\n", __func__, "SIOCSIFFLAGS");
-		if (IS_RUNNING(ifp)) {
-			DWTAP_PRINTF("running\n");
-#if 0
-			/*
-			 * To avoid rescanning another access point,
-			 * do not call ath_init() here.  Instead,
-			 * only reflect promisc mode settings.
-			 */
-			//ath_mode_init(sc);
-#endif
-			} else if (ifp->if_flags & IFF_UP) {
-			DWTAP_PRINTF("up\n");
-			sc->up = 1;
-#if 0
-			/*
-			 * Beware of being called during attach/detach
-			 * to reset promiscuous mode.  In that case we
-			 * will still be marked UP but not RUNNING.
-			 * However trying to re-init the interface
-			 * is the wrong thing to do as we've already
-			 * torn down much of our state.  There's
-			 * probably a better way to deal with this.
-			 */
-			//if (!sc->sc_invalid)
-			//	ath_init(sc);	/* XXX lose error */
-#endif
-			ifp->if_drv_flags |= IFF_DRV_RUNNING;
-			ieee80211_start_all(ic);
-		} else {
-			DWTAP_PRINTF("stoping\n");
-#if 0
-			ath_stop_locked(ifp);
-#ifdef notyet
-			/* XXX must wakeup in places like ath_vap_delete */
-			if (!sc->sc_invalid)
-				ath_hal_setpower(sc->sc_ah, HAL_PM_FULL_SLEEP);
-#endif
-#endif
-		}
-		break;
-	case SIOCGIFMEDIA:
-	case SIOCSIFMEDIA:
-#if 0
-		DWTAP_PRINTF("%s: %s\n", __func__, "SIOCGIFMEDIA|SIOCSIFMEDIA");
-#endif
-		error = ifmedia_ioctl(ifp, ifr, &ic->ic_media, cmd);
-		break;
-	case SIOCGIFADDR:
-#if 0
-		DWTAP_PRINTF("%s: %s\n", __func__, "SIOCGIFADDR");
-#endif
-		error = ether_ioctl(ifp, cmd, data);
-		break;
-	default:
-		DWTAP_PRINTF("%s: %s [%lu]\n", __func__, "EINVAL", cmd);
-		error = EINVAL;
-		break;
-	}
-	return error;
-#undef IS_RUNNING
-}
-
-static void
-wtap_init(void *arg){
+	struct wtap_softc *sc = ic->ic_softc;
 
-	DWTAP_PRINTF("%s\n", __func__);
+	if (ic->ic_nrunning > 0) {
+		sc->up = 1;
+		ieee80211_start_all(ic);
+	} else
+		sc->up = 0;
 }
 
 static void
@@ -581,8 +448,7 @@ wtap_inject(struct wtap_softc *sc, struct mbuf *m)
 void
 wtap_rx_deliver(struct wtap_softc *sc, struct mbuf *m)
 {
-	struct ifnet *ifp = sc->sc_ifp;
-	struct ieee80211com *ic = ifp->if_l2com;
+	struct ieee80211com *ic = &sc->sc_ic;
 	struct ieee80211_node *ni;
 	int type;
 #if 0
@@ -591,11 +457,9 @@ wtap_rx_deliver(struct wtap_softc *sc, struct mbuf *m)
 
 	DWTAP_PRINTF("[%d] receiving m=%p\n", sc->id, m);
 	if (m == NULL) {		/* NB: shouldn't happen */
-		if_printf(ifp, "%s: no mbuf!\n", __func__);
+		ic_printf(ic, "%s: no mbuf!\n", __func__);
 	}
 
-	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
-
 	ieee80211_dump_pkt(ic, mtod(m, caddr_t), 0,0,0);
 
 	/*
@@ -620,8 +484,7 @@ static void
 wtap_rx_proc(void *arg, int npending)
 {
 	struct wtap_softc *sc = (struct wtap_softc *)arg;
-	struct ifnet *ifp = sc->sc_ifp;
-	struct ieee80211com *ic = ifp->if_l2com;
+	struct ieee80211com *ic = &sc->sc_ic;
 	struct mbuf *m;
 	struct ieee80211_node *ni;
 	int type;
@@ -644,12 +507,10 @@ wtap_rx_proc(void *arg, int npending)
 		m = bf->m;
 		DWTAP_PRINTF("[%d] receiving m=%p\n", sc->id, bf->m);
 		if (m == NULL) {		/* NB: shouldn't happen */
-			if_printf(ifp, "%s: no mbuf!\n", __func__);
+			ic_printf(ic, "%s: no mbuf!\n", __func__);
 			free(bf, M_WTAP_RXBUF);
 			return;
 		}
-
-		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
 #if 0
 		ieee80211_dump_pkt(ic, mtod(m, caddr_t), 0,0,0);
 #endif
@@ -716,7 +577,7 @@ wtap_update_promisc(struct ieee80211com *ic)
 }
 
 static int
-wtap_if_transmit(struct ifnet *ifp, struct mbuf *m)
+wtap_transmit(struct ieee80211com *ic, struct mbuf *m)
 {
 	struct ieee80211_node *ni =
 	    (struct ieee80211_node *) m->m_pkthdr.rcvif;
@@ -753,7 +614,7 @@ static void
 wtap_node_free(struct ieee80211_node *ni)
 {
 	struct ieee80211com *ic = ni->ni_ic;
-	struct wtap_softc *sc = ic->ic_ifp->if_softc;
+	struct wtap_softc *sc = ic->ic_softc;
 
 	DWTAP_PRINTF("%s\n", __func__);
 	sc->sc_node_free(ni);
@@ -762,41 +623,17 @@ wtap_node_free(struct ieee80211_node *ni)
 int32_t
 wtap_attach(struct wtap_softc *sc, const uint8_t *macaddr)
 {
-	struct ifnet *ifp;
-	struct ieee80211com *ic;
-	char wtap_name[] = {'w','T','a','p',sc->id,
-	    '_','t','a','s','k','q','\0'};
+	struct ieee80211com *ic = &sc->sc_ic;
 
 	DWTAP_PRINTF("%s\n", __func__);
 
-	ifp = if_alloc(IFT_IEEE80211);
-	if (ifp == NULL) {
-		printf("can not if_alloc()\n");
-		return -1;
-	}
-	ic = ifp->if_l2com;
-	if_initname(ifp, "wtap", sc->id);
-
-	sc->sc_ifp = ifp;
 	sc->up = 0;
-
 	STAILQ_INIT(&sc->sc_rxbuf);
-	sc->sc_tq = taskqueue_create(wtap_name, M_NOWAIT | M_ZERO,
+	sc->sc_tq = taskqueue_create("wtap_taskq", M_NOWAIT | M_ZERO,
 	    taskqueue_thread_enqueue, &sc->sc_tq);
-	taskqueue_start_threads(&sc->sc_tq, 1, PI_SOFT, "%s taskQ",
-	    ifp->if_xname);
+	taskqueue_start_threads(&sc->sc_tq, 1, PI_SOFT, "%s taskQ", sc->name);
 	TASK_INIT(&sc->sc_rxtask, 0, wtap_rx_proc, sc);
 
-	ifp->if_softc = sc;
-	ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
-	ifp->if_start = wtap_start;
-	ifp->if_ioctl = wtap_ioctl;
-	ifp->if_init = wtap_init;
-	IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
-	ifp->if_snd.ifq_drv_maxlen = ifqmaxlen;
-	IFQ_SET_READY(&ifp->if_snd);
-
-	ic->ic_ifp = ifp;
 	ic->ic_softc = sc;
 	ic->ic_name = sc->name;
 	ic->ic_phytype = IEEE80211_T_DS;
@@ -815,17 +652,8 @@ wtap_attach(struct wtap_softc *sc, const uint8_t *macaddr)
 	ic->ic_channels[0].ic_flags = IEEE80211_CHAN_B;
 	ic->ic_channels[0].ic_freq = 2412;
 
-	ieee80211_ifattach(ic, macaddr);
-
-#if 0
-	/* new prototype hook-ups */
-	msc->if_input = ifp->if_input;
-	ifp->if_input = myath_if_input;
-	msc->if_output = ifp->if_output;
-	ifp->if_output = myath_if_output;
-#endif
-	sc->if_transmit = ifp->if_transmit;
-	ifp->if_transmit = wtap_if_transmit;
+	IEEE80211_ADDR_COPY(ic->ic_macaddr, macaddr);
+	ieee80211_ifattach(ic);
 
 	/* override default methods */
 	ic->ic_newassoc = wtap_newassoc;
@@ -835,15 +663,14 @@ wtap_attach(struct wtap_softc *sc, const uint8_t *macaddr)
 	ic->ic_raw_xmit = wtap_raw_xmit;
 	ic->ic_update_mcast = wtap_update_mcast;
 	ic->ic_update_promisc = wtap_update_promisc;
+	ic->ic_transmit = wtap_transmit;
+	ic->ic_parent = wtap_parent;
 
 	sc->sc_node_alloc = ic->ic_node_alloc;
 	ic->ic_node_alloc = wtap_node_alloc;
 	sc->sc_node_free = ic->ic_node_free;
 	ic->ic_node_free = wtap_node_free;
 
-#if 0
-	ic->ic_node_getsignal = myath_node_getsignal;
-#endif
 	ic->ic_scan_start = wtap_scan_start;
 	ic->ic_scan_end = wtap_scan_end;
 	ic->ic_set_channel = wtap_set_channel;
@@ -882,13 +709,11 @@ wtap_attach(struct wtap_softc *sc, const uint8_t *macaddr)
 int32_t
 wtap_detach(struct wtap_softc *sc)
 {
-	struct ifnet *ifp = sc->sc_ifp;
-	struct ieee80211com *ic = ifp->if_l2com;
+	struct ieee80211com *ic = &sc->sc_ic;
 
 	DWTAP_PRINTF("%s\n", __func__);
 	ieee80211_ageq_drain(&ic->ic_stageq);
 	ieee80211_ifdetach(ic);
-	if_free(ifp);
 	return 0;
 }
 
diff --git a/sys/dev/wtap/if_wtapvar.h b/sys/dev/wtap/if_wtapvar.h
index a886be9..04a1818 100644
--- a/sys/dev/wtap/if_wtapvar.h
+++ b/sys/dev/wtap/if_wtapvar.h
@@ -130,18 +130,14 @@ struct wtap_vap {
 struct taskqueue;
 
 struct wtap_softc {
+	struct ieee80211com	sc_ic;
 	char 			name[7];	/* wtapXX\0 */
 	int32_t			id;
 	int32_t			up;
-	struct ifnet		*sc_ifp;	/* interface common */
 	struct wtap_medium	*sc_md;		/* interface medium */
 	struct ieee80211_node*	(* sc_node_alloc)
 	    (struct ieee80211vap *, const uint8_t [IEEE80211_ADDR_LEN]);
 	void (*sc_node_free)(struct ieee80211_node *);
-	int (*if_output)			/* output routine (enqueue) */
-	    (struct ifnet *, struct mbuf *, struct sockaddr *, struct route *);
-	void (*if_input) (struct ifnet *, struct mbuf *);/* from h/w driver */
-	int (*if_transmit)(struct ifnet *, struct mbuf *);/* output routine */
 	struct mtx		sc_mtx;		/* master lock (recursive) */
 	struct taskqueue	*sc_tq;		/* private task queue */
 	wtap_bufhead		sc_rxbuf;	/* receive buffer */