diff options
Diffstat (limited to 'kernel/include/uapi/linux/const.h')
-rw-r--r-- | kernel/include/uapi/linux/const.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/kernel/include/uapi/linux/const.h b/kernel/include/uapi/linux/const.h new file mode 100644 index 000000000..c872bfd25 --- /dev/null +++ b/kernel/include/uapi/linux/const.h @@ -0,0 +1,27 @@ +/* const.h: Macros for dealing with constants. */ + +#ifndef _LINUX_CONST_H +#define _LINUX_CONST_H + +/* Some constant macros are used in both assembler and + * C code. Therefore we cannot annotate them always with + * 'UL' and other type specifiers unilaterally. We + * use the following macros to deal with this. + * + * Similarly, _AT() will cast an expression with a type in C, but + * leave it unchanged in asm. + */ + +#ifdef __ASSEMBLY__ +#define _AC(X,Y) X +#define _AT(T,X) X +#else +#define __AC(X,Y) (X##Y) +#define _AC(X,Y) __AC(X,Y) +#define _AT(T,X) ((T)(X)) +#endif + +#define _BITUL(x) (_AC(1,UL) << (x)) +#define _BITULL(x) (_AC(1,ULL) << (x)) + +#endif /* !(_LINUX_CONST_H) */ |