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#ifndef __ARCH_X86_64_ATOMIC__

#define __ARCH_X86_64_ATOMIC__

#include <linux/config.h>

/* atomic_t should be 32 bit signed type */

/*

 * Atomic operations that C can't guarantee us.  Useful for

 * resource counting etc..

 */

#ifdef CONFIG_SMP

#define LOCK "lock ; "

#else

#define LOCK ""

#endif

/*

 * Make sure gcc doesn't try to be clever and move things around

 * on us. We need to use _exactly_ the address the user gave us,

 * not some alias that contains the same information.

 */

typedef struct { volatile int counter; } atomic_t;

#define ATOMIC_INIT(i)  { (i) }

/**

 * atomic_read - read atomic variable

 * @v: pointer of type atomic_t

 *

 * Atomically reads the value of @v.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

#define atomic_read(v)          ((v)->counter)

/**

 * atomic_set - set atomic variable

 * @v: pointer of type atomic_t

 * @i: required value

 *

 * Atomically sets the value of @v to @i.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

#define atomic_set(v,i)         (((v)->counter) = (i))

/**

 * atomic_add - add integer to atomic variable

 * @i: integer value to add

 * @v: pointer of type atomic_t

 *

 * Atomically adds @i to @v.  Note that the guaranteed useful range

 * of an atomic_t is only 24 bits.

 */

static __inline__ void atomic_add(int i, atomic_t *v)

{

        __asm__ __volatile__(

                LOCK "addl %1,%0"

                :"=m" (v->counter)

                :"ir" (i), "m" (v->counter));

}

/**

 * atomic_sub - subtract the atomic variable

 * @i: integer value to subtract

 * @v: pointer of type atomic_t

 *

 * Atomically subtracts @i from @v.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ void atomic_sub(int i, atomic_t *v)

{

        __asm__ __volatile__(

                LOCK "subl %1,%0"

                :"=m" (v->counter)

                :"ir" (i), "m" (v->counter));

}

/**

 * atomic_sub_and_test - subtract value from variable and test result

 * @i: integer value to subtract

 * @v: pointer of type atomic_t

 *

 * Atomically subtracts @i from @v and returns

 * true if the result is zero, or false for all

 * other cases.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ int atomic_sub_and_test(int i, atomic_t *v)

{

        unsigned char c;

        __asm__ __volatile__(

                LOCK "subl %2,%0; sete %1"

                :"=m" (v->counter), "=qm" (c)

                :"ir" (i), "m" (v->counter) : "memory");

        return c;

}

/**

 * atomic_inc - increment atomic variable

 * @v: pointer of type atomic_t

 *

 * Atomically increments @v by 1.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ void atomic_inc(atomic_t *v)

{

        __asm__ __volatile__(

                LOCK "incl %0"

                :"=m" (v->counter)

                :"m" (v->counter));

}

/**

 * atomic_dec - decrement atomic variable

 * @v: pointer of type atomic_t

 *

 * Atomically decrements @v by 1.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ void atomic_dec(atomic_t *v)

{

        __asm__ __volatile__(

                LOCK "decl %0"

                :"=m" (v->counter)

                :"m" (v->counter));

}

/**

 * atomic_dec_and_test - decrement and test

 * @v: pointer of type atomic_t

 *

 * Atomically decrements @v by 1 and

 * returns true if the result is 0, or false for all other

 * cases.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ int atomic_dec_and_test(atomic_t *v)

{

        unsigned char c;

        __asm__ __volatile__(

                LOCK "decl %0; sete %1"

                :"=m" (v->counter), "=qm" (c)

                :"m" (v->counter) : "memory");

        return c != 0;

}

/**

 * atomic_inc_and_test - increment and test

 * @v: pointer of type atomic_t

 *

 * Atomically increments @v by 1

 * and returns true if the result is zero, or false for all

 * other cases.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ int atomic_inc_and_test(atomic_t *v)

{

        unsigned char c;

        __asm__ __volatile__(

                LOCK "incl %0; sete %1"

                :"=m" (v->counter), "=qm" (c)

                :"m" (v->counter) : "memory");

        return c != 0;

}

/**

 * atomic_add_negative - add and test if negative

 * @v: pointer of type atomic_t

 * @i: integer value to add

 *

 * Atomically adds @i to @v and returns true

 * if the result is negative, or false when

 * result is greater than or equal to zero.  Note that the guaranteed

 * useful range of an atomic_t is only 24 bits.

 */

static __inline__ int atomic_add_negative(int i, atomic_t *v)

{

        unsigned char c;

        __asm__ __volatile__(

                LOCK "addl %2,%0; sets %1"

                :"=m" (v->counter), "=qm" (c)

                :"ir" (i), "m" (v->counter) : "memory");

        return c;

}

/* These are x86-specific, used by some header files */

#define atomic_clear_mask(mask, addr) \

__asm__ __volatile__(LOCK "andl %0,%1" \

: : "r" (~(mask)),"m" (*addr) : "memory")

#define atomic_set_mask(mask, addr) \

__asm__ __volatile__(LOCK "orl %0,%1" \

: : "r" ((unsigned)mask),"m" (*addr) : "memory")

/* Atomic operations are already serializing on x86 */

#define smp_mb__before_atomic_dec()     barrier()

#define smp_mb__after_atomic_dec()      barrier()

#define smp_mb__before_atomic_inc()     barrier()

#define smp_mb__after_atomic_inc()      barrier()

#endif