diff options
| -rw-r--r-- | include/asm-generic/bitsperlong.h | 8 | ||||
| -rw-r--r-- | include/linux/bitops.h | 11 |
2 files changed, 19 insertions, 0 deletions
diff --git a/include/asm-generic/bitsperlong.h b/include/asm-generic/bitsperlong.h new file mode 100644 index 0000000..75ee21e --- /dev/null +++ b/include/asm-generic/bitsperlong.h @@ -0,0 +1,8 @@ +#ifndef __ASM_GENERIC_BITS_PER_LONG +#define __ASM_GENERIC_BITS_PER_LONG + +#ifndef BITS_PER_LONG_LONG +#define BITS_PER_LONG_LONG 64 +#endif + +#endif /* __ASM_GENERIC_BITS_PER_LONG */ diff --git a/include/linux/bitops.h b/include/linux/bitops.h index e9bb827..7b4011f 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -8,6 +8,17 @@ #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 * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). |