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#ifndef _ASM_X86_ATOMIC64_32_H
#define _ASM_X86_ATOMIC64_32_H
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/processor.h>
//#include <asm/cmpxchg.h>
/* An 64bit atomic type */
typedef struct {
u64 __aligned(8) counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
#ifdef CONFIG_X86_CMPXCHG64
#define ATOMIC64_ALTERNATIVE_(f, g) "call atomic64_" #g "_cx8"
#else
#define ATOMIC64_ALTERNATIVE_(f, g) ALTERNATIVE("call atomic64_" #f "_386", "call atomic64_" #g "_cx8", X86_FEATURE_CX8)
#endif
#define ATOMIC64_ALTERNATIVE(f) ATOMIC64_ALTERNATIVE_(f, f)
/**
* atomic64_cmpxchg - cmpxchg atomic64 variable
* @p: pointer to type atomic64_t
* @o: expected value
* @n: new value
*
* Atomically sets @v to @n if it was equal to @o and returns
* the old value.
*/
static inline long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n)
{
return cmpxchg64(&v->counter, o, n);
}
/**
* atomic64_xchg - xchg atomic64 variable
* @v: pointer to type atomic64_t
* @n: value to assign
*
* Atomically xchgs the value of @v to @n and returns
* the old value.
*/
static inline long long atomic64_xchg(atomic64_t *v, long long n)
{
long long o;
unsigned high = (unsigned)(n >> 32);
unsigned low = (unsigned)n;
asm volatile(ATOMIC64_ALTERNATIVE(xchg)
: "=A" (o), "+b" (low), "+c" (high)
: "S" (v)
: "memory"
);
return o;
}
/**
* atomic64_set - set atomic64 variable
* @v: pointer to type atomic64_t
* @n: value to assign
*
* Atomically sets the value of @v to @n.
*/
static inline void atomic64_set(atomic64_t *v, long long i)
{
unsigned high = (unsigned)(i >> 32);
unsigned low = (unsigned)i;
asm volatile(ATOMIC64_ALTERNATIVE(set)
: "+b" (low), "+c" (high)
: "S" (v)
: "eax", "edx", "memory"
);
}
/**
* atomic64_read - read atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically reads the value of @v and returns it.
*/
static inline long long atomic64_read(atomic64_t *v)
{
long long r;
asm volatile(ATOMIC64_ALTERNATIVE(read)
: "=A" (r), "+c" (v)
: : "memory"
);
return r;
}
/**
* atomic64_add_return - add and return
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns @i + *@v
*/
static inline long long atomic64_add_return(long long i, atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE(add_return)
: "+A" (i), "+c" (v)
: : "memory"
);
return i;
}
/*
* Other variants with different arithmetic operators:
*/
static inline long long atomic64_sub_return(long long i, atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE(sub_return)
: "+A" (i), "+c" (v)
: : "memory"
);
return i;
}
static inline long long atomic64_inc_return(atomic64_t *v)
{
long long a;
asm volatile(ATOMIC64_ALTERNATIVE(inc_return)
: "=A" (a)
: "S" (v)
: "memory", "ecx"
);
return a;
}
static inline long long atomic64_dec_return(atomic64_t *v)
{
long long a;
asm volatile(ATOMIC64_ALTERNATIVE(dec_return)
: "=A" (a)
: "S" (v)
: "memory", "ecx"
);
return a;
}
/**
* atomic64_add - add integer to atomic64 variable
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v.
*/
static inline long long atomic64_add(long long i, atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE_(add, add_return)
: "+A" (i), "+c" (v)
: : "memory"
);
return i;
}
/**
* atomic64_sub - subtract the atomic64 variable
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v.
*/
static inline long long atomic64_sub(long long i, atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE_(sub, sub_return)
: "+A" (i), "+c" (v)
: : "memory"
);
return i;
}
/**
* atomic64_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
static inline int atomic64_sub_and_test(long long i, atomic64_t *v)
{
return atomic64_sub_return(i, v) == 0;
}
/**
* atomic64_inc - increment atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1.
*/
static inline void atomic64_inc(atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE_(inc, inc_return)
: : "S" (v)
: "memory", "eax", "ecx", "edx"
);
}
/**
* atomic64_dec - decrement atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically decrements @ptr by 1.
*/
static inline void atomic64_dec(atomic64_t *v)
{
asm volatile(ATOMIC64_ALTERNATIVE_(dec, dec_return)
: : "S" (v)
: "memory", "eax", "ecx", "edx"
);
}
/**
* atomic64_dec_and_test - decrement and test
* @v: pointer to type atomic64_t
*
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all other
* cases.
*/
static inline int atomic64_dec_and_test(atomic64_t *v)
{
return atomic64_dec_return(v) == 0;
}
/**
* atomic64_inc_and_test - increment and test
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
static inline int atomic64_inc_and_test(atomic64_t *v)
{
return atomic64_inc_return(v) == 0;
}
/**
* atomic64_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
static inline int atomic64_add_negative(long long i, atomic64_t *v)
{
return atomic64_add_return(i, v) < 0;
}
/**
* atomic64_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
{
unsigned low = (unsigned)u;
unsigned high = (unsigned)(u >> 32);
asm volatile(ATOMIC64_ALTERNATIVE(add_unless) "\n\t"
: "+A" (a), "+c" (v), "+S" (low), "+D" (high)
: : "memory");
return (int)a;
}
static inline int atomic64_inc_not_zero(atomic64_t *v)
{
int r;
asm volatile(ATOMIC64_ALTERNATIVE(inc_not_zero)
: "=a" (r)
: "S" (v)
: "ecx", "edx", "memory"
);
return r;
}
static inline long long atomic64_dec_if_positive(atomic64_t *v)
{
long long r;
asm volatile(ATOMIC64_ALTERNATIVE(dec_if_positive)
: "=A" (r)
: "S" (v)
: "ecx", "memory"
);
return r;
}
#undef ATOMIC64_ALTERNATIVE
#undef ATOMIC64_ALTERNATIVE_
#endif /* _ASM_X86_ATOMIC64_32_H */
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