diff options
Diffstat (limited to 'include/linux/bitops.h')
| -rw-r--r-- | include/linux/bitops.h | 68 |
1 files changed, 19 insertions, 49 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index c05a29cb9bb2..2184c6b97aeb 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -10,22 +10,26 @@ #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) #endif +extern unsigned int __sw_hweight8(unsigned int w); +extern unsigned int __sw_hweight16(unsigned int w); +extern unsigned int __sw_hweight32(unsigned int w); +extern unsigned long __sw_hweight64(__u64 w); + /* * Include this here because some architectures need generic_ffs/fls in * scope */ #include <asm/bitops.h> -#define for_each_bit(bit, addr, size) \ +#define for_each_set_bit(bit, addr, size) \ for ((bit) = find_first_bit((addr), (size)); \ (bit) < (size); \ (bit) = find_next_bit((addr), (size), (bit) + 1)) - static __inline__ int get_bitmask_order(unsigned int count) { int order; - + order = fls(count); return order; /* We could be slightly more clever with -1 here... */ } @@ -33,7 +37,7 @@ static __inline__ int get_bitmask_order(unsigned int count) static __inline__ int get_count_order(unsigned int count) { int order; - + order = fls(count) - 1; if (count & (count - 1)) order++; @@ -105,6 +109,17 @@ static inline __u8 ror8(__u8 word, unsigned int shift) return (word >> shift) | (word << (8 - shift)); } +/** + * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit + * @value: value to sign extend + * @index: 0 based bit index (0<=index<32) to sign bit + */ +static inline __s32 sign_extend32(__u32 value, int index) +{ + __u8 shift = 31 - index; + return (__s32)(value << shift) >> shift; +} + static inline unsigned fls_long(unsigned long l) { if (sizeof(l) == 4) @@ -132,28 +147,6 @@ static inline unsigned long __ffs64(u64 word) } #ifdef __KERNEL__ -#ifdef CONFIG_GENERIC_FIND_FIRST_BIT - -/** - * find_first_bit - find the first set bit in a memory region - * @addr: The address to start the search at - * @size: The maximum size to search - * - * Returns the bit number of the first set bit. - */ -extern unsigned long find_first_bit(const unsigned long *addr, - unsigned long size); - -/** - * find_first_zero_bit - find the first cleared bit in a memory region - * @addr: The address to start the search at - * @size: The maximum size to search - * - * Returns the bit number of the first cleared bit. - */ -extern unsigned long find_first_zero_bit(const unsigned long *addr, - unsigned long size); -#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */ #ifdef CONFIG_GENERIC_FIND_LAST_BIT /** @@ -167,28 +160,5 @@ extern unsigned long find_last_bit(const unsigned long *addr, unsigned long size); #endif /* CONFIG_GENERIC_FIND_LAST_BIT */ -#ifdef CONFIG_GENERIC_FIND_NEXT_BIT - -/** - * find_next_bit - find the next set bit in a memory region - * @addr: The address to base the search on - * @offset: The bitnumber to start searching at - * @size: The bitmap size in bits - */ -extern unsigned long find_next_bit(const unsigned long *addr, - unsigned long size, unsigned long offset); - -/** - * find_next_zero_bit - find the next cleared bit in a memory region - * @addr: The address to base the search on - * @offset: The bitnumber to start searching at - * @size: The bitmap size in bits - */ - -extern unsigned long find_next_zero_bit(const unsigned long *addr, - unsigned long size, - unsigned long offset); - -#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */ #endif /* __KERNEL__ */ #endif |