diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bitops.h | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 7d30ace..7b4011f 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -3,7 +3,20 @@ #include <asm/types.h> -#define BIT(nr) (1UL << (nr)) +#define BIT(nr) (1UL << (nr)) +#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) + +/* + * 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. + */ +#define GENMASK(h, l) \ + (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) + +#define GENMASK_ULL(h, l) \ + (((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h)))) /* * ffs: find first bit set. This is defined the same way as @@ -106,9 +119,6 @@ static inline unsigned int generic_hweight8(unsigned int w) return (res & 0x0F) + ((res >> 4) & 0x0F); } -#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) -#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) - #include <asm/bitops.h> /* linux/include/asm-generic/bitops/non-atomic.h */ |