--- zzzz-none-000/linux-3.10.107/lib/div64.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/lib/div64.c 2021-02-04 17:41:59.000000000 +0000 @@ -79,6 +79,46 @@ #endif /** + * div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder + * @dividend: 64bit dividend + * @divisor: 64bit divisor + * @remainder: 64bit remainder + * + * This implementation is a comparable to algorithm used by div64_u64. + * But this operation, which includes math for calculating the remainder, + * is kept distinct to avoid slowing down the div64_u64 operation on 32bit + * systems. + */ +#ifndef div64_u64_rem +u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder) +{ + u32 high = divisor >> 32; + u64 quot; + + if (high == 0) { + u32 rem32; + quot = div_u64_rem(dividend, divisor, &rem32); + *remainder = rem32; + } else { + int n = 1 + fls(high); + quot = div_u64(dividend >> n, divisor >> n); + + if (quot != 0) + quot--; + + *remainder = dividend - quot * divisor; + if (*remainder >= divisor) { + quot++; + *remainder -= divisor; + } + } + + return quot; +} +EXPORT_SYMBOL(div64_u64_rem); +#endif + +/** * div64_u64 - unsigned 64bit divide with 64bit divisor * @dividend: 64bit dividend * @divisor: 64bit divisor @@ -87,7 +127,7 @@ * by the book 'Hacker's Delight'. The original source and full proof * can be found here and is available for use without restriction. * - * 'http://www.hackersdelight.org/HDcode/newCode/divDouble.c.txt' + * 'http://www.hackersdelight.org/hdcodetxt/divDouble.c.txt' */ #ifndef div64_u64 u64 div64_u64(u64 dividend, u64 divisor) @@ -122,7 +162,7 @@ { s64 quot, t; - quot = div64_u64(abs64(dividend), abs64(divisor)); + quot = div64_u64(abs(dividend), abs(divisor)); t = (dividend ^ divisor) >> 63; return (quot ^ t) - t;