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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_BITS_H
#define __LINUX_BITS_H
#include <linux/const.h>
#include <vdso/bits.h>
#include <uapi/linux/bits.h>
#include <asm/bitsperlong.h>
#define BIT_MASK(nr) (UL(1) << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define BIT_ULL_MASK(nr) (ULL(1) << ((nr) % BITS_PER_LONG_LONG))
#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
#define BITS_PER_BYTE 8
/*
* Create a contiguous bitmask starting at bit position @l and ending at
* position @h. For example
* GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
*/
#if !defined(__ASSEMBLY__)
#include <linux/build_bug.h>
#define GENMASK_INPUT_CHECK(h, l) \
(BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
__is_constexpr((l) > (h)), (l) > (h), 0)))
#else
/*
* BUILD_BUG_ON_ZERO is not available in h files included from asm files,
* disable the input check if that is the case.
*/
#define GENMASK_INPUT_CHECK(h, l) 0
#endif
#define GENMASK(h, l) \
(GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
#define GENMASK_ULL(h, l) \
(GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
#if !defined(__ASSEMBLY__)
/*
* Missing asm support
*
* __GENMASK_U128() depends on _BIT128() which would not work
* in the asm code, as it shifts an 'unsigned __init128' data
* type instead of direct representation of 128 bit constants
* such as long and unsigned long. The fundamental problem is
* that a 128 bit constant will get silently truncated by the
* gcc compiler.
*/
#define GENMASK_U128(h, l) \
(GENMASK_INPUT_CHECK(h, l) + __GENMASK_U128(h, l))
#endif
#endif /* __LINUX_BITS_H */
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