bitops.h 1.3 KB
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#ifndef _LINUX_BITOPS_H
#define _LINUX_BITOPS_H
#include <asm/types.h>

/*
 * 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;
	
	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;
	
	order = fls(count) - 1;
	if (count & (count - 1))
		order++;
	return order;
}

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static inline unsigned long hweight_long(unsigned long w)
{
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	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
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}

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/**
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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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/**
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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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static inline unsigned fls_long(unsigned long l)
{
	if (sizeof(l) == 4)
		return fls(l);
	return fls64(l);
}

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#endif