0,0 → 1,191 |
#ifndef _LINUX_BITOPS_H |
#define _LINUX_BITOPS_H |
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#define BIT(nr) (1UL << (nr)) |
#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) |
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) |
#define BITS_PER_BYTE 8 |
#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) |
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/* |
* Include this here because some architectures need generic_ffs/fls in |
* scope |
*/ |
#include <asm/bitops.h> |
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#define for_each_bit(bit, addr, size) \ |
for ((bit) = find_first_bit((addr), (size)); \ |
(bit) < (size); \ |
(bit) = find_next_bit((addr), (size), (bit) + 1)) |
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static __inline__ int get_bitmask_order(unsigned int count) |
{ |
int order; |
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order = fls(count); |
return order; /* We could be slightly more clever with -1 here... */ |
} |
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static __inline__ int get_count_order(unsigned int count) |
{ |
int order; |
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order = fls(count) - 1; |
if (count & (count - 1)) |
order++; |
return order; |
} |
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static inline unsigned long hweight_long(unsigned long w) |
{ |
return sizeof(w) == 4 ? hweight32(w) : hweight64(w); |
} |
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/** |
* rol32 - rotate a 32-bit value left |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u32 rol32(__u32 word, unsigned int shift) |
{ |
return (word << shift) | (word >> (32 - shift)); |
} |
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/** |
* ror32 - rotate a 32-bit value right |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u32 ror32(__u32 word, unsigned int shift) |
{ |
return (word >> shift) | (word << (32 - shift)); |
} |
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/** |
* rol16 - rotate a 16-bit value left |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u16 rol16(__u16 word, unsigned int shift) |
{ |
return (word << shift) | (word >> (16 - shift)); |
} |
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/** |
* ror16 - rotate a 16-bit value right |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u16 ror16(__u16 word, unsigned int shift) |
{ |
return (word >> shift) | (word << (16 - shift)); |
} |
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/** |
* rol8 - rotate an 8-bit value left |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u8 rol8(__u8 word, unsigned int shift) |
{ |
return (word << shift) | (word >> (8 - shift)); |
} |
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/** |
* ror8 - rotate an 8-bit value right |
* @word: value to rotate |
* @shift: bits to roll |
*/ |
static inline __u8 ror8(__u8 word, unsigned int shift) |
{ |
return (word >> shift) | (word << (8 - shift)); |
} |
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static inline unsigned fls_long(unsigned long l) |
{ |
if (sizeof(l) == 4) |
return fls(l); |
return fls64(l); |
} |
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/** |
* __ffs64 - find first set bit in a 64 bit word |
* @word: The 64 bit word |
* |
* On 64 bit arches this is a synomyn for __ffs |
* The result is not defined if no bits are set, so check that @word |
* is non-zero before calling this. |
*/ |
static inline unsigned long __ffs64(u64 word) |
{ |
#if BITS_PER_LONG == 32 |
if (((u32)word) == 0UL) |
return __ffs((u32)(word >> 32)) + 32; |
#elif BITS_PER_LONG != 64 |
#error BITS_PER_LONG not 32 or 64 |
#endif |
return __ffs((unsigned long)word); |
} |
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#ifdef __KERNEL__ |
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT |
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/** |
* 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); |
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/** |
* 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 */ |
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#ifdef CONFIG_GENERIC_FIND_LAST_BIT |
/** |
* find_last_bit - find the last 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, or size. |
*/ |
extern unsigned long find_last_bit(const unsigned long *addr, |
unsigned long size); |
#endif /* CONFIG_GENERIC_FIND_LAST_BIT */ |
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#ifdef CONFIG_GENERIC_FIND_NEXT_BIT |
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/** |
* 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); |
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/** |
* 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 |
*/ |
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extern unsigned long find_next_zero_bit(const unsigned long *addr, |
unsigned long size, |
unsigned long offset); |
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#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */ |
#endif /* __KERNEL__ */ |
#endif |