const.h 935 B

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  1. /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2. /* const.h: Macros for dealing with constants. */
  3. #ifndef _LINUX_CONST_H
  4. #define _LINUX_CONST_H
  5. /* Some constant macros are used in both assembler and
  6. * C code. Therefore we cannot annotate them always with
  7. * 'UL' and other type specifiers unilaterally. We
  8. * use the following macros to deal with this.
  9. *
  10. * Similarly, _AT() will cast an expression with a type in C, but
  11. * leave it unchanged in asm.
  12. */
  13. #ifdef __ASSEMBLY__
  14. #define _AC(X,Y) X
  15. #define _AT(T,X) X
  16. #else
  17. #define __AC(X,Y) (X##Y)
  18. #define _AC(X,Y) __AC(X,Y)
  19. #define _AT(T,X) ((T)(X))
  20. #endif
  21. #define _BITUL(x) (_AC(1,UL) << (x))
  22. #define _BITULL(x) (_AC(1,ULL) << (x))
  23. #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
  24. #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
  25. #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
  26. #endif /* !(_LINUX_CONST_H) */