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#ifndef _LINUX_MATH64_H
#define _LINUX_MATH64_H
#include <linux/types.h>
#define do_div(n,base) ({ \
u32 __base = (base); \
u32 __rem; \
__rem = ((u64)(n)) % __base; \
(n) = ((u64)(n)) / __base; \
__rem; \
})
#define div64_long(x, y) div64_s64((x), (y))
#define div64_ul(x, y) div64_u64((x), (y))
/**
* div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
*
* This is commonly provided by 32bit archs to provide an optimized 64bit
* divide.
*/
static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
{
*remainder = dividend % divisor;
return dividend / divisor;
}
/**
* div_s64_rem - signed 64bit divide with 32bit divisor with remainder
*/
static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
{
*remainder = dividend % divisor;
return dividend / divisor;
}
/**
* div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder
*/
static inline u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder)
{
*remainder = dividend % divisor;
return dividend / divisor;
}
/**
* div64_u64 - unsigned 64bit divide with 64bit divisor
*/
static inline u64 div64_u64(u64 dividend, u64 divisor)
{
return dividend / divisor;
}
/**
* div64_s64 - signed 64bit divide with 64bit divisor
*/
static inline s64 div64_s64(s64 dividend, s64 divisor)
{
return dividend / divisor;
}
/**
* div_u64 - unsigned 64bit divide with 32bit divisor
*
* This is the most common 64bit divide and should be used if possible,
* as many 32bit archs can optimize this variant better than a full 64bit
* divide.
*/
static inline u64 div_u64(u64 dividend, u32 divisor)
{
u32 remainder;
return div_u64_rem(dividend, divisor, &remainder);
}
/**
* div_s64 - signed 64bit divide with 32bit divisor
*/
static inline s64 div_s64(s64 dividend, s32 divisor)
{
s32 remainder;
return div_s64_rem(dividend, divisor, &remainder);
}
#ifndef mul_u32_u32
/*
* Many a GCC version messes this up and generates a 64x64 mult :-(
*/
static inline u64 mul_u32_u32(u32 a, u32 b)
{
return (u64)a * b;
}
#endif
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
#ifndef mul_u64_u64_shr
static __always_inline u64 mul_u64_u64_shr(u64 a, u64 mul, unsigned int shift)
{
return (u64)(((unsigned __int128)a * mul) >> shift);
}
#endif /* mul_u64_u64_shr */
#else
#ifndef mul_u64_u64_shr
static inline u64 mul_u64_u64_shr(u64 a, u64 b, unsigned int shift)
{
union {
u64 ll;
struct {
#ifdef __BIG_ENDIAN
u32 high, low;
#else
u32 low, high;
#endif
} l;
} rl, rm, rn, rh, a0, b0;
u64 c;
a0.ll = a;
b0.ll = b;
rl.ll = mul_u32_u32(a0.l.low, b0.l.low);
rm.ll = mul_u32_u32(a0.l.low, b0.l.high);
rn.ll = mul_u32_u32(a0.l.high, b0.l.low);
rh.ll = mul_u32_u32(a0.l.high, b0.l.high);
/*
* Each of these lines computes a 64-bit intermediate result into "c",
* starting at bits 32-95. The low 32-bits go into the result of the
* multiplication, the high 32-bits are carried into the next step.
*/
rl.l.high = c = (u64)rl.l.high + rm.l.low + rn.l.low;
rh.l.low = c = (c >> 32) + rm.l.high + rn.l.high + rh.l.low;
rh.l.high = (c >> 32) + rh.l.high;
/*
* The 128-bit result of the multiplication is in rl.ll and rh.ll,
* shift it right and throw away the high part of the result.
*/
if (shift == 0)
return rl.ll;
if (shift < 64)
return (rl.ll >> shift) | (rh.ll << (64 - shift));
return rh.ll >> (shift & 63);
}
#endif /* mul_u64_u64_shr */
#endif
#endif /* _LINUX_MATH64_H */
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