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#ifndef _ASM_GENERIC_BITOPS_H_
#define _ASM_GENERIC_BITOPS_H_
/*
* For the benefit of those who are trying to port Linux to another
* architecture, here are some C-language equivalents. You should
* recode these in the native assembly language, if at all possible.
* To guarantee atomicity, these routines call cli() and sti() to
* disable interrupts while they operate. (You have to provide inline
* routines to cli() and sti().)
*
* Also note, these routines assume that you have 32 bit integers.
* You will have to change this if you are trying to port Linux to the
* Alpha architecture or to a Cray. :-)
*
* C language equivalents written by Theodore Ts'o, 9/26/92
*/
extern __inline__ int set_bit(int nr,int * addr)
{
int mask, retval;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
cli();
retval = (mask & *addr) != 0;
*addr |= mask;
sti();
return retval;
}
extern __inline__ int clear_bit(int nr, int * addr)
{
int mask, retval;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
cli();
retval = (mask & *addr) != 0;
*addr &= ~mask;
sti();
return retval;
}
extern __inline__ int test_bit(int nr, int * addr)
{
int mask;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
return ((mask & *addr) != 0);
}
#ifdef __KERNEL__
/*
* ffs: find first bit set. This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz (man ffs).
*/
#define ffs(x) generic_ffs(x)
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
*/
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
#endif /* __KERNEL__ */
#endif /* _ASM_GENERIC_BITOPS_H */
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