xref: /linux/tools/include/linux/bits.h (revision 71e2f4dd5a65bd8dbca0b77661e75eea471168f8)
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 */
30