math64.h 1.8 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586
  1. #ifndef _LINUX_MATH64_H
  2. #define _LINUX_MATH64_H
  3. #include <linux/types.h>
  4. #include <asm/div64.h>
  5. #if BITS_PER_LONG == 64
  6. /**
  7. * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
  8. *
  9. * This is commonly provided by 32bit archs to provide an optimized 64bit
  10. * divide.
  11. */
  12. static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
  13. {
  14. *remainder = dividend % divisor;
  15. return dividend / divisor;
  16. }
  17. /**
  18. * div_s64_rem - signed 64bit divide with 32bit divisor with remainder
  19. */
  20. static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
  21. {
  22. *remainder = dividend % divisor;
  23. return dividend / divisor;
  24. }
  25. /**
  26. * div64_u64 - unsigned 64bit divide with 64bit divisor
  27. */
  28. static inline u64 div64_u64(u64 dividend, u64 divisor)
  29. {
  30. return dividend / divisor;
  31. }
  32. #elif BITS_PER_LONG == 32
  33. #ifndef div_u64_rem
  34. static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
  35. {
  36. *remainder = do_div(dividend, divisor);
  37. return dividend;
  38. }
  39. #endif
  40. #ifndef div_s64_rem
  41. extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
  42. #endif
  43. #ifndef div64_u64
  44. extern u64 div64_u64(u64 dividend, u64 divisor);
  45. #endif
  46. #endif /* BITS_PER_LONG */
  47. /**
  48. * div_u64 - unsigned 64bit divide with 32bit divisor
  49. *
  50. * This is the most common 64bit divide and should be used if possible,
  51. * as many 32bit archs can optimize this variant better than a full 64bit
  52. * divide.
  53. */
  54. #ifndef div_u64
  55. static inline u64 div_u64(u64 dividend, u32 divisor)
  56. {
  57. u32 remainder;
  58. return div_u64_rem(dividend, divisor, &remainder);
  59. }
  60. #endif
  61. /**
  62. * div_s64 - signed 64bit divide with 32bit divisor
  63. */
  64. #ifndef div_s64
  65. static inline s64 div_s64(s64 dividend, s32 divisor)
  66. {
  67. s32 remainder;
  68. return div_s64_rem(dividend, divisor, &remainder);
  69. }
  70. #endif
  71. u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
  72. #endif /* _LINUX_MATH64_H */