Commit d54385ce authored by Alexander Duyck's avatar Alexander Duyck Committed by David S. Miller
Browse files

etherdev: Process is_multicast_ether_addr at same size as other operations 



This change makes it so that we process the address in
is_multicast_ether_addr at the same size as the other calls.  This allows
us to avoid duplicate reads when used with other calls such as
is_zero_ether_addr or eth_addr_copy.  In addition I have added a 64 bit
version of the function so in eth_type_trans we can process the destination
address as a 64 bit value throughout.

Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 849b920e

include/linux/etherdevice.h

+23 −1
Original line number Diff line number Diff line
@@ -110,7 +110,29 @@ static inline bool is_zero_ether_addr(const u8 *addr) 
 */

static inline bool is_multicast_ether_addr(const u8 *addr)

{

	return 0x01 & addr[0];

#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)

	u32 a = *(const u32 *)addr;

#else

	u16 a = *(const u16 *)addr;

#endif

#ifdef __BIG_ENDIAN

	return 0x01 & (a >> ((sizeof(a) * 8) - 8));

#else

	return 0x01 & a;

#endif

}



static inline bool is_multicast_ether_addr_64bits(const u8 addr[6+2])

{

#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64

#ifdef __BIG_ENDIAN

	return 0x01 & ((*(const u64 *)addr) >> 56);

#else

	return 0x01 & (*(const u64 *)addr);

#endif

#else

	return is_multicast_ether_addr(addr);

#endif

}



/**

net/ethernet/eth.c

+1 −1
Original line number Diff line number Diff line
@@ -159,7 +159,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) 
	skb_pull_inline(skb, ETH_HLEN);

	eth = eth_hdr(skb);



	if (unlikely(is_multicast_ether_addr(eth->h_dest))) {

	if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) {

		if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))

			skb->pkt_type = PACKET_BROADCAST;

		else

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