Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_BITS_H
3#define __LINUX_BITS_H
4
5#include <linux/const.h>
6#include <asm/bitsperlong.h>
7
8#define BIT(nr) (UL(1) << (nr))
9#define BIT_ULL(nr) (ULL(1) << (nr))
10#define BIT_MASK(nr) (UL(1) << ((nr) % BITS_PER_LONG))
11#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
12#define BIT_ULL_MASK(nr) (ULL(1) << ((nr) % BITS_PER_LONG_LONG))
13#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
14#define BITS_PER_BYTE 8
15
16/*
17 * Create a contiguous bitmask starting at bit position @l and ending at
18 * position @h. For example
19 * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
20 */
21#define GENMASK(h, l) \
22 (((~UL(0)) - (UL(1) << (l)) + 1) & \
23 (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
24
25#define GENMASK_ULL(h, l) \
26 (((~ULL(0)) - (ULL(1) << (l)) + 1) & \
27 (~ULL(0) >> (BITS_PER_LONG_LONG - 1 - (h))))
28
29#endif /* __LINUX_BITS_H */