[netdevice] Allow the hardware and link-layer addresses to differ in size

IPoIB has a 20-byte link-layer address, of which only eight bytes
represent anything relating to a "hardware address".

The PXE and EFI SNP APIs expect the permanent address to be the same
size as the link-layer address, so fill in the "permanent address"
field with the initial link layer address (as generated by
register_netdev() based upon the real hardware address).

src/net/80211/net80211.c

@@ -602,9 +602,11 @@ static struct ll_protocol net80211_ll_protocol __ll_protocol = {
 	.name = "802.11",
 	.push = net80211_ll_push,
 	.pull = net80211_ll_pull,
+	.init_addr = eth_init_addr,
 	.ntoa = eth_ntoa,
 	.mc_hash = net80211_ll_mc_hash,
 	.ll_proto = htons ( ARPHRD_ETHER ),	/* "encapsulated Ethernet" */
+	.hw_addr_len = ETH_ALEN,
 	.ll_addr_len = ETH_ALEN,
 	.ll_header_len = IEEE80211_TYP_FRAME_HEADER_LEN +
 				IEEE80211_LLC_HEADER_LEN,

src/net/ethernet.c

@@ -96,6 +96,16 @@ static int eth_pull ( struct net_device *netdev __unused,
 	return 0;
 }
 
+/**
+ * Initialise Ethernet address
+ *
+ * @v hw_addr		Hardware address
+ * @v ll_addr		Link-layer address
+ */
+void eth_init_addr ( const void *hw_addr, void *ll_addr ) {
+	memcpy ( ll_addr, hw_addr, ETH_ALEN );
+}
+
 /**
  * Transcribe Ethernet address
  *
@@ -143,10 +153,12 @@ static int eth_mc_hash ( unsigned int af, const void *net_addr,
 struct ll_protocol ethernet_protocol __ll_protocol = {
 	.name		= "Ethernet",
 	.ll_proto	= htons ( ARPHRD_ETHER ),
+	.hw_addr_len	= ETH_ALEN,
 	.ll_addr_len	= ETH_ALEN,
 	.ll_header_len	= ETH_HLEN,
 	.push		= eth_push,
 	.pull		= eth_pull,
+	.init_addr	= eth_init_addr,
 	.ntoa		= eth_ntoa,
 	.mc_hash	= eth_mc_hash,
 };

src/net/netdevice.c

@@ -358,8 +358,7 @@ int register_netdev ( struct net_device *netdev ) {
 		   ifindex++ );
 
 	/* Set initial link-layer address */
-	memcpy ( netdev->ll_addr, netdev->hw_addr,
-		 netdev->ll_protocol->ll_addr_len );
+	netdev->ll_protocol->init_addr ( netdev->hw_addr, netdev->ll_addr );
 
 	/* Register per-netdev configuration settings */
 	if ( ( rc = register_settings ( netdev_settings ( netdev ),