diff options
Diffstat (limited to 'include/net/checksum.h')
| -rw-r--r-- | include/net/checksum.h | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/include/net/checksum.h b/include/net/checksum.h index 10a16b5bd1c7..5c30891e84e5 100644 --- a/include/net/checksum.h +++ b/include/net/checksum.h @@ -88,8 +88,11 @@ static inline __wsum csum_block_add(__wsum csum, __wsum csum2, int offset) { u32 sum = (__force u32)csum2; - if (offset&1) - sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); + + /* rotate sum to align it with a 16b boundary */ + if (offset & 1) + sum = ror32(sum, 8); + return csum_add(csum, (__force __wsum)sum); } @@ -102,10 +105,7 @@ csum_block_add_ext(__wsum csum, __wsum csum2, int offset, int len) static inline __wsum csum_block_sub(__wsum csum, __wsum csum2, int offset) { - u32 sum = (__force u32)csum2; - if (offset&1) - sum = ((sum&0xFF00FF)<<8)+((sum>>8)&0xFF00FF); - return csum_sub(csum, (__force __wsum)sum); + return csum_block_add(csum, ~csum2, offset); } static inline __wsum csum_unfold(__sum16 n) @@ -120,6 +120,11 @@ static inline __wsum csum_partial_ext(const void *buff, int len, __wsum sum) #define CSUM_MANGLED_0 ((__force __sum16)0xffff) +static inline void csum_replace_by_diff(__sum16 *sum, __wsum diff) +{ + *sum = csum_fold(csum_add(diff, ~csum_unfold(*sum))); +} + static inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to) { __wsum tmp = csum_sub(~csum_unfold(*sum), (__force __wsum)from); |