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);
}
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)
#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);