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#ifndef __ASM_SH_ATOMIC_H

#define __ASM_SH_ATOMIC_H

/*

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

 * resource counting etc..

 *

 */

typedef struct { volatile int counter; } atomic_t;

#define ATOMIC_INIT(i)  ( (atomic_t) { (i) } )

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

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

#include <asm/system.h>

/*

 * To get proper branch prediction for the main line, we must branch

 * forward to code at the end of this object's .text section, then

 * branch back to restart the operation.

 */

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

{

        unsigned long flags;

        save_and_cli(flags);

        *(long *)v += i;

        restore_flags(flags);

}

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

{

        unsigned long flags;

        save_and_cli(flags);

        *(long *)v -= i;

        restore_flags(flags);

}

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

{

        unsigned long temp, flags;

        save_and_cli(flags);

        temp = *(long *)v;

        temp += i;

        *(long *)v = temp;

        restore_flags(flags);

        return temp;

}

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

{

        unsigned long temp, flags;

        save_and_cli(flags);

        temp = *(long *)v;

        temp -= i;

        *(long *)v = temp;

        restore_flags(flags);

        return temp;

}

#define atomic_dec_return(v) atomic_sub_return(1,(v))

#define atomic_inc_return(v) atomic_add_return(1,(v))

#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)

#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)

#define atomic_inc(v) atomic_add(1,(v))

#define atomic_dec(v) atomic_sub(1,(v))

static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v)

{

        unsigned long flags;

        save_and_cli(flags);

        *(long *)v &= ~mask;

        restore_flags(flags);

}

static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v)

{

        unsigned long flags;

        save_and_cli(flags);

        *(long *)v |= mask;

        restore_flags(flags);

}

/* Atomic operations are already serializing on SH */

#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 /* __ASM_SH_ATOMIC_H */