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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */2/* const.h: Macros for dealing with constants. */3 4#ifndef _UAPI_LINUX_CONST_H5#define _UAPI_LINUX_CONST_H6 7/* Some constant macros are used in both assembler and8 * C code. Therefore we cannot annotate them always with9 * 'UL' and other type specifiers unilaterally. We10 * use the following macros to deal with this.11 *12 * Similarly, _AT() will cast an expression with a type in C, but13 * leave it unchanged in asm.14 */15 16#ifdef __ASSEMBLY__17#define _AC(X,Y) X18#define _AT(T,X) X19#else20#define __AC(X,Y) (X##Y)21#define _AC(X,Y) __AC(X,Y)22#define _AT(T,X) ((T)(X))23#endif24 25#define _UL(x) (_AC(x, UL))26#define _ULL(x) (_AC(x, ULL))27 28#define _BITUL(x) (_UL(1) << (x))29#define _BITULL(x) (_ULL(1) << (x))30 31#if !defined(__ASSEMBLY__)32/*33 * Missing asm support34 *35 * __BIT128() would not work in the asm code, as it shifts an36 * 'unsigned __init128' data type as direct representation of37 * 128 bit constants is not supported in the gcc compiler, as38 * they get silently truncated.39 *40 * TODO: Please revisit this implementation when gcc compiler41 * starts representing 128 bit constants directly like long42 * and unsigned long etc. Subsequently drop the comment for43 * GENMASK_U128() which would then start supporting asm code.44 */45#define _BIT128(x) ((unsigned __int128)(1) << (x))46#endif47 48#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (__typeof__(x))(a) - 1)49#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))50 51#define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))52 53#endif /* _UAPI_LINUX_CONST_H */54