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#ifndef _TOOLS_LINUX_BITOPS_H_
#define _TOOLS_LINUX_BITOPS_H_

#include <asm/types.h>
#include <linux/kernel.h>
#include <linux/compiler.h>
#include <linux/page.h>

#ifndef __WORDSIZE
#define __WORDSIZE (__SIZEOF_LONG__ * 8)
#endif

#ifndef BITS_PER_LONG
# define BITS_PER_LONG __WORDSIZE
#endif

#define BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr)		((nr) / BITS_PER_LONG)
#define BITS_PER_TYPE(type)	(sizeof(type) * BITS_PER_BYTE)
#define BITS_PER_BYTE		8
#define BITS_TO_LONGS(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
#define BITS_TO_U64(nr)		DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
#define BITS_TO_U32(nr)		DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
#define BITS_TO_BYTES(nr)	DIV_ROUND_UP(nr, BITS_PER_BYTE)

static inline void __set_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	*p  |= mask;
}

static inline void set_bit(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	__atomic_or_fetch(p, mask, __ATOMIC_RELAXED);
}

static inline void __clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	*p &= ~mask;
}

static inline void clear_bit(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	__atomic_and_fetch(p, ~mask, __ATOMIC_RELAXED);
}

static inline int test_bit(long nr, const volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *) addr) + BIT_WORD(nr);

	return (*p & mask) != 0;
}

static inline int __test_and_set_bit(int nr, unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	unsigned long old;

	old = *p;
	*p = old | mask;

	return (old & mask) != 0;
}

static inline bool test_and_set_bit(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *) addr) + BIT_WORD(nr);
	unsigned long old;

	old = __atomic_fetch_or(p, mask, __ATOMIC_RELAXED);

	return (old & mask) != 0;
}

static inline bool test_and_clear_bit(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *) addr) + BIT_WORD(nr);
	unsigned long old;

	old = __atomic_fetch_and(p, ~mask, __ATOMIC_RELAXED);

	return (old & mask) != 0;
}

static inline void clear_bit_unlock(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	__atomic_and_fetch(p, ~mask, __ATOMIC_RELEASE);
}

static inline bool test_and_set_bit_lock(long nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *) addr) + BIT_WORD(nr);
	unsigned long old;

	old = __atomic_fetch_or(p, mask, __ATOMIC_ACQUIRE);

	return (old & mask) != 0;
}

#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))

/* same as for_each_set_bit() but use bit as value to start with */
#define for_each_set_bit_from(bit, addr, size) \
	for ((bit) = find_next_bit((addr), (size), (bit));	\
	     (bit) < (size);					\
	     (bit) = find_next_bit((addr), (size), (bit) + 1))

static inline unsigned long hweight_long(unsigned long w)
{
	return __builtin_popcountl(w);
}

static inline unsigned long hweight64(u64 w)
{
	return __builtin_popcount((u32) w) +
	       __builtin_popcount(w >> 32);
}

static inline unsigned long hweight32(u32 w)
{
	return __builtin_popcount(w);
}

static inline unsigned long hweight8(unsigned long w)
{
	return __builtin_popcountl(w);
}

/**
 * rol64 - rotate a 64-bit value left
 * @word: value to rotate
 * @shift: bits to roll
 */
static inline __u64 rol64(__u64 word, unsigned int shift)
{
	return (word << shift) | (word >> (64 - shift));
}

/**
 * ror64 - rotate a 64-bit value right
 * @word: value to rotate
 * @shift: bits to roll
 */
static inline __u64 ror64(__u64 word, unsigned int shift)
{
	return (word >> shift) | (word << (64 - shift));
}

/**
 * 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 >> ((-shift) & 31));
}

/**
 * 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));
}

/**
 * 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));
}

/**
 * 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));
}

/**
 * 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));
}

/**
 * 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));
}

static inline unsigned long __fls(unsigned long word)
{
	return (sizeof(word) * 8) - 1 - __builtin_clzl(word);
}

static inline int fls(int x)
{
	return x ? sizeof(x) * 8 - __builtin_clz(x) : 0;
}

static inline int fls64(__u64 x)
{
#if BITS_PER_LONG == 32
	__u32 h = x >> 32;
	if (h)
		return fls(h) + 32;
	return fls(x);
#elif BITS_PER_LONG == 64
	if (x == 0)
		return 0;
	return __fls(x) + 1;
#endif
}

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

static inline unsigned long __ffs(unsigned long word)
{
	return __builtin_ctzl(word);
}

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);
}

#define ffz(x)  __ffs(~(x))

static inline __attribute__((const))
unsigned long rounddown_pow_of_two(unsigned long n)
{
	return 1UL << (fls_long(n) - 1);
}

#endif