From 2c7a88c252bf3381958cf716f31b6b2e0f2f3fa7 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Mon, 4 May 2015 14:33:48 -0700 Subject: etherdev: Fix sparse error, make test usable by other functions This change does two things. First it fixes a sparse error for the fact that the __be16 degrades to an integer. Since that is actually what I am kind of doing I am simply working around that by forcing both sides of the comparison to u16. Also I realized on some compilers I was generating another instruction for big endian systems such as PowerPC since it was masking the value before doing the comparison. So to resolve that I have simply pulled the mask out and wrapped it in an #ifndef __BIG_ENDIAN. Lastly I pulled this all out into its own function. I notices there are similar checks in a number of other places so this function can be reused there to help reduce overhead in these paths as well. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 18 ++++++++++++++++++ net/ethernet/eth.c | 2 +- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index c4a10f991fe0..9012f8775208 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -190,6 +190,24 @@ static inline bool is_valid_ether_addr(const u8 *addr) return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr); } +/** + * eth_proto_is_802_3 - Determine if a given Ethertype/length is a protocol + * @proto: Ethertype/length value to be tested + * + * Check that the value from the Ethertype/length field is a valid Ethertype. + * + * Return true if the valid is an 802.3 supported Ethertype. + */ +static inline bool eth_proto_is_802_3(__be16 proto) +{ +#ifndef __BIG_ENDIAN + /* if CPU is little endian mask off bits representing LSB */ + proto &= htons(0xFF00); +#endif + /* cast both to u16 and compare since LSB can be ignored */ + return (__force u16)proto >= (__force u16)htons(ETH_P_802_3_MIN); +} + /** * eth_random_addr - Generate software assigned random Ethernet address * @addr: Pointer to a six-byte array containing the Ethernet address diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 314e4c5a5a5e..9045e2a1108f 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -179,7 +179,7 @@ __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev) if (unlikely(netdev_uses_dsa(dev))) return htons(ETH_P_XDSA); - if (likely((eth->h_proto & htons(0xFF00)) >= htons(ETH_P_802_3_MIN))) + if (likely(eth_proto_is_802_3(eth->h_proto))) return eth->h_proto; /* -- cgit