xref: /linux/tools/include/linux/bits.h (revision 44f57d78)
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 */
27