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| author | Alexander Duyck <alexander.h.duyck@redhat.com> | 2015-05-04 14:33:48 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-05-05 19:24:42 -0400 |
| commit | 2c7a88c252bf3381958cf716f31b6b2e0f2f3fa7 (patch) | |
| tree | 8c242beda53e88b084af505aaa4039f1c1f3f2e6 | |
| parent | 784b58a327ad16967ab64bbfa558df81980d31e9 (diff) | |
| download | linux-2c7a88c252bf3381958cf716f31b6b2e0f2f3fa7.tar.bz2 | |
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 <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/etherdevice.h | 18 | ||||
| -rw-r--r-- | net/ethernet/eth.c | 2 |
2 files changed, 19 insertions, 1 deletions
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 @@ -191,6 +191,24 @@ static inline bool is_valid_ether_addr(const u8 *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; /* |