Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_BITS_H
3#define __LINUX_BITS_H
4#include <asm/bitsperlong.h>
5
6#define BIT(nr) (1UL << (nr))
7#define BIT_ULL(nr) (1ULL << (nr))
8#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
9#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
10#define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
11#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
12#define BITS_PER_BYTE 8
13
14/*
15 * Create a contiguous bitmask starting at bit position @l and ending at
16 * position @h. For example
17 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
18 */
19#define GENMASK(h, l) \
20 (((~0UL) - (1UL << (l)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
21
22#define GENMASK_ULL(h, l) \
23 (((~0ULL) - (1ULL << (l)) + 1) & \
24 (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
25
26#endif /* __LINUX_BITS_H */