1 #ifndef _LINUX_MATH64_H
2 #define _LINUX_MATH64_H
4 #include <linux/types.h>
7 #if BITS_PER_LONG == 64
10 * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
12 * This is commonly provided by 32bit archs to provide an optimized 64bit
15 static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
17 *remainder = dividend % divisor;
18 return dividend / divisor;
22 * div_s64_rem - signed 64bit divide with 32bit divisor with remainder
24 static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
26 *remainder = dividend % divisor;
27 return dividend / divisor;
31 * div64_u64 - unsigned 64bit divide with 64bit divisor
33 static inline u64 div64_u64(u64 dividend, u64 divisor)
35 return dividend / divisor;
39 * div64_s64 - signed 64bit divide with 64bit divisor
41 static inline s64 div64_s64(s64 dividend, s64 divisor)
43 return dividend / divisor;
46 #elif BITS_PER_LONG == 32
49 static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
51 *remainder = do_div(dividend, divisor);
57 extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
61 extern u64 div64_u64(u64 dividend, u64 divisor);
65 extern s64 div64_s64(s64 dividend, s64 divisor);
68 #endif /* BITS_PER_LONG */
71 * div_u64 - unsigned 64bit divide with 32bit divisor
73 * This is the most common 64bit divide and should be used if possible,
74 * as many 32bit archs can optimize this variant better than a full 64bit
78 static inline u64 div_u64(u64 dividend, u32 divisor)
81 return div_u64_rem(dividend, divisor, &remainder);
86 * div_s64 - signed 64bit divide with 32bit divisor
89 static inline s64 div_s64(s64 dividend, s32 divisor)
92 return div_s64_rem(dividend, divisor, &remainder);
96 u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
98 static __always_inline u32
99 __iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
103 while (dividend >= divisor) {
104 /* The following asm() prevents the compiler from
105 optimising this loop into a modulo operation. */
106 asm("" : "+rm"(dividend));
112 *remainder = dividend;
117 #endif /* _LINUX_MATH64_H */