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#ifndef __ARCH_M68K_ATOMIC__
#define __ARCH_M68K_ATOMIC__
#include <linux/types.h>
#include <linux/irqflags.h>
#include <asm/cmpxchg.h>
#include <asm/barrier.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/
/*
* We do not have SMP m68k systems, so we don't have to deal with that.
*/
#define ATOMIC_INIT(i) { (i) }
#define atomic_read(v) READ_ONCE((v)->counter)
#define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
/*
* The ColdFire parts cannot do some immediate to memory operations,
* so for them we do not specify the "i" asm constraint.
*/
#ifdef CONFIG_COLDFIRE
#define ASM_DI "d"
#else
#define ASM_DI "di"
#endif
#define ATOMIC_OP(op, c_op, asm_op) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
__asm__ __volatile__(#asm_op "l %1,%0" : "+m" (*v) : ASM_DI (i));\
} \
#ifdef CONFIG_RMW_INSNS
#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
static inline int atomic_##op##_return(int i, atomic_t *v) \
{ \
int t, tmp; \
\
__asm__ __volatile__( \
"1: movel %2,%1\n" \
" " #asm_op "l %3,%1\n" \
" casl %2,%1,%0\n" \
" jne 1b" \
: "+m" (*v), "=&d" (t), "=&d" (tmp) \
: "g" (i), "2" (atomic_read(v))); \
return t; \
}
#else
#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
static inline int atomic_##op##_return(int i, atomic_t * v) \
{ \
unsigned long flags; \
int t; \
\
local_irq_save(flags); \
t = (v->counter c_op i); \
local_irq_restore(flags); \
\
return t; \
}
#endif /* CONFIG_RMW_INSNS */
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
ATOMIC_OP(and, &=, and)
ATOMIC_OP(or, |=, or)
ATOMIC_OP(xor, ^=, eor)
#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
static inline void atomic_inc(atomic_t *v)
{
__asm__ __volatile__("addql #1,%0" : "+m" (*v));
}
static inline void atomic_dec(atomic_t *v)
{
__asm__ __volatile__("subql #1,%0" : "+m" (*v));
}
static inline int atomic_dec_and_test(atomic_t *v)
{
char c;
__asm__ __volatile__("subql #1,%1; seq %0" : "=d" (c), "+m" (*v));
return c != 0;
}
static inline int atomic_dec_and_test_lt(atomic_t *v)
{
char c;
__asm__ __volatile__(
"subql #1,%1; slt %0"
: "=d" (c), "=m" (*v)
: "m" (*v));
return c != 0;
}
static inline int atomic_inc_and_test(atomic_t *v)
{
char c;
__asm__ __volatile__("addql #1,%1; seq %0" : "=d" (c), "+m" (*v));
return c != 0;
}
#ifdef CONFIG_RMW_INSNS
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
#else /* !CONFIG_RMW_INSNS */
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
unsigned long flags;
int prev;
local_irq_save(flags);
prev = atomic_read(v);
if (prev == old)
atomic_set(v, new);
local_irq_restore(flags);
return prev;
}
static inline int atomic_xchg(atomic_t *v, int new)
{
unsigned long flags;
int prev;
local_irq_save(flags);
prev = atomic_read(v);
atomic_set(v, new);
local_irq_restore(flags);
return prev;
}
#endif /* !CONFIG_RMW_INSNS */
#define atomic_dec_return(v) atomic_sub_return(1, (v))
#define atomic_inc_return(v) atomic_add_return(1, (v))
static inline int atomic_sub_and_test(int i, atomic_t *v)
{
char c;
__asm__ __volatile__("subl %2,%1; seq %0"
: "=d" (c), "+m" (*v)
: ASM_DI (i));
return c != 0;
}
static inline int atomic_add_negative(int i, atomic_t *v)
{
char c;
__asm__ __volatile__("addl %2,%1; smi %0"
: "=d" (c), "+m" (*v)
: ASM_DI (i));
return c != 0;
}
static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
for (;;) {
if (unlikely(c == (u)))
break;
old = atomic_cmpxchg((v), c, c + (a));
if (likely(old == c))
break;
c = old;
}
return c;
}
#endif /* __ARCH_M68K_ATOMIC __ */
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