Stop embedding struct ifnet at the top of driver softcs. Instead the

struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
 - Struct arpcom is no longer referenced in normal interface code.
   Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
   To enforce this ac_enaddr has been renamed to _ac_enaddr.
 - The second argument to ether_ifattach is now always the mac address
   from driver private storage rather than sometimes being ac_enaddr.

Reviewed by:	sobomax, sam

2 files changed, 12 insertions, 3 deletions

diff --git a/sys/dev/iwi/if_iwi.c b/sys/dev/iwi/if_iwi.c
index 8e219f5..d5a1bc4 100644
--- a/sys/dev/iwi/if_iwi.c
+++ b/sys/dev/iwi/if_iwi.c
@@ -229,7 +229,7 @@ static int
 iwi_attach(device_t dev)
 {
 	struct iwi_softc *sc = device_get_softc(dev);
-	struct ifnet *ifp = &sc->sc_arp.ac_if;
+	struct ifnet *ifp;
 	struct ieee80211com *ic = &sc->sc_ic;
 	uint16_t val;
 	int error, i;
@@ -292,6 +292,12 @@ iwi_attach(device_t dev)
 		goto fail;
 	}
 
+	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
+	if (ifp == NULL) {
+		device_printf(dev, "can not if_alloc()\n");
+		goto fail;
+		return (ENOSPC);
+	}
 	ifp->if_softc = sc;
 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
@@ -435,8 +441,11 @@ iwi_detach(device_t dev)
 
 	iwi_free_firmware(sc);
 
-	bpfdetach(ifp);
+	if (ifp != NULL)
+		bpfdetach(ifp);
 	ieee80211_ifdetach(ic);
+	if (ifp != NULL)
+		if_free(ifp);
 
 	iwi_free_cmd_ring(sc, &sc->cmdq);
 	iwi_free_tx_ring(sc, &sc->txq);
diff --git a/sys/dev/iwi/if_iwivar.h b/sys/dev/iwi/if_iwivar.h
index 705aa1a..2e8bcab 100644
--- a/sys/dev/iwi/if_iwivar.h
+++ b/sys/dev/iwi/if_iwivar.h
@@ -109,7 +109,7 @@ struct iwi_rx_ring {
 };
 
 struct iwi_softc {
-	struct arpcom		sc_arp;
+	struct ifnet		*sc_ifp;
 	struct ieee80211com	sc_ic;
 	int			(*sc_newstate)(struct ieee80211com *,
 				    enum ieee80211_state, int);