#ifndef _ASM_BITOPS_H#define _ASM_BITOPS_H/* * Copyright 1992, Linus Torvalds. */#ifdef i386/* * These have to be done with inline assembly: that way the bit-setting * is guaranteed to be atomic. All bitoperations return 0 if the bit * was cleared before the operation and != 0 if it was not. * * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). *//* * Some hacks to defeat gcc over-optimizations.. */struct __dummy { unsigned long a[100]; };#define ADDR (*(struct __dummy *) addr)extern __inline__ int set_bit(int nr, void * addr){	int oldbit;	__asm__ __volatile__("btsl %2,%1\n\tsbbl %0,%0"		:"=r" (oldbit),"=m" (ADDR)		:"r" (nr));	return oldbit;}extern __inline__ int clear_bit(int nr, void * addr){	int oldbit;	__asm__ __volatile__("btrl %2,%1\n\tsbbl %0,%0"		:"=r" (oldbit),"=m" (ADDR)		:"r" (nr));	return oldbit;}/* * This routine doesn't need to be atomic, but it's faster to code it * this way. */extern __inline__ int test_bit(int nr, void * addr){	int oldbit;	__asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0"		:"=r" (oldbit)		:"m" (ADDR),"r" (nr));	return oldbit;}#else/* * 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 assmebly 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);}#endif	/* i386 */#endif /* _ASM_BITOPS_H */