non-atomic.h

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#ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_
#define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_

#include <asm/types.h>

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 __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 __change_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 int __test_and_set_bit(int nr, volatile unsigned long *addr)
{
    unsigned long mask = BIT_MASK(nr);
    unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
    unsigned long old = *p;

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

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

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

/* WARNING: non atomic and it can be reordered! */
static inline int __test_and_change_bit(int nr,
                        volatile unsigned long *addr)
{
    unsigned long mask = BIT_MASK(nr);
    unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
    unsigned long old = *p;

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

static inline int test_bit(int nr, const volatile unsigned long *addr)
{
    return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}

#endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */