1 #ifndef _LINUX_MATH64_H
2 #define _LINUX_MATH64_H
4 #include <linux/types.h>
7 #if BITS_PER_LONG == 64
9 #define div64_long(x,y) div64_s64((x),(y))
12 * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
14 * This is commonly provided by 32bit archs to provide an optimized 64bit
17 static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
19 *remainder = dividend % divisor;
20 return dividend / divisor;
24 * div_s64_rem - signed 64bit divide with 32bit divisor with remainder
26 static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
28 *remainder = dividend % divisor;
29 return dividend / divisor;
33 * div64_u64_rem - unsigned 64bit divide with 64bit divisor
35 static inline u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder)
37 *remainder = dividend % divisor;
38 return dividend / divisor;
42 * div64_u64 - unsigned 64bit divide with 64bit divisor
44 static inline u64 div64_u64(u64 dividend, u64 divisor)
46 return dividend / divisor;
50 * div64_s64 - signed 64bit divide with 64bit divisor
52 static inline s64 div64_s64(s64 dividend, s64 divisor)
54 return dividend / divisor;
57 #elif BITS_PER_LONG == 32
59 #define div64_long(x,y) div_s64((x),(y))
62 static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
64 *remainder = do_div(dividend, divisor);
70 extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
74 extern u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder);
78 static inline u64 div64_u64(u64 dividend, u64 divisor)
81 return div64_u64_rem(dividend, divisor, &remainder);
86 extern s64 div64_s64(s64 dividend, s64 divisor);
89 #endif /* BITS_PER_LONG */
92 * div_u64 - unsigned 64bit divide with 32bit divisor
94 * This is the most common 64bit divide and should be used if possible,
95 * as many 32bit archs can optimize this variant better than a full 64bit
99 static inline u64 div_u64(u64 dividend, u32 divisor)
102 return div_u64_rem(dividend, divisor, &remainder);
107 * div_s64 - signed 64bit divide with 32bit divisor
110 static inline s64 div_s64(s64 dividend, s32 divisor)
113 return div_s64_rem(dividend, divisor, &remainder);
117 u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
119 static __always_inline u32
120 __iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
124 while (dividend >= divisor) {
125 /* The following asm() prevents the compiler from
126 optimising this loop into a modulo operation. */
127 asm("" : "+rm"(dividend));
133 *remainder = dividend;
138 #endif /* _LINUX_MATH64_H */