/* * PowerPC64 atomic bit operations. * Dave Engebretsen, Todd Inglett, Don Reed, Pat McCarthy, Peter Bergner, * Anton Blanchard * * Originally taken from the 32b PPC code.  Modified to use 64b values for * the various counters & memory references. * * Bitops are odd when viewed on big-endian systems.  They were designed * on little endian so the size of the bitset doesn't matter (low order bytes * come first) as long as the bit in question is valid. * * Bits are "tested" often using the C expression (val & (1<<nr)) so we do * our best to stay compatible with that.  The assumption is that val will * be unsigned long for such tests.  As such, we assume the bits are stored * as an array of unsigned long (the usual case is a single unsigned long, * of course).  Here's an example bitset with bit numbering: * *   |63..........0|127........64|195.......128|255.......196| * * This leads to a problem. If an int, short or char is passed as a bitset * it will be a bad memory reference since we want to store in chunks * of unsigned long (64 bits here) size. * * There are a few little-endian macros used mostly for filesystem bitmaps, * these work on similar bit arrays layouts, but byte-oriented: * *   |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56| * * The main difference is that bit 3-5 in the bit number field needs to be * reversed compared to the big-endian bit fields. This can be achieved * by XOR with 0b111000 (0x38). * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #ifndef _PPC64_BITOPS_H#define _PPC64_BITOPS_H #ifdef __KERNEL__ #include <asm/memory.h> /* * clear_bit doesn't imply a memory barrier */#define smp_mb__before_clear_bit()	smp_mb()#define smp_mb__after_clear_bit()	smp_mb() static __inline__ int test_bit(unsigned long nr, __const__ volatile unsigned long *addr){	return (1UL & (addr[nr >> 6] >> (nr & 63)));} static __inline__ void set_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__("1:	ldarx	%0,0,%3		# set_bit\n\	or	%0,%0,%2\n\	stdcx.	%0,0,%3\n\	bne-	1b"	: "=&r" (old), "=m" (*p)	: "r" (mask), "r" (p), "m" (*p)	: "cc");} static __inline__ void clear_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__("1:	ldarx	%0,0,%3		# clear_bit\n\	andc	%0,%0,%2\n\	stdcx.	%0,0,%3\n\	bne-	1b"	: "=&r" (old), "=m" (*p)	: "r" (mask), "r" (p), "m" (*p)	: "cc");} static __inline__ void change_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__("1:	ldarx	%0,0,%3		# change_bit\n\	xor	%0,%0,%2\n\	stdcx.	%0,0,%3\n\	bne-	1b"	: "=&r" (old), "=m" (*p)	: "r" (mask), "r" (p), "m" (*p)	: "cc");} static __inline__ int test_and_set_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old, t;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__(	EIEIO_ON_SMP"1:	ldarx	%0,0,%3		# test_and_set_bit\n\	or	%1,%0,%2 \n\	stdcx.	%1,0,%3 \n\	bne-	1b"	ISYNC_ON_SMP	: "=&r" (old), "=&r" (t)	: "r" (mask), "r" (p)	: "cc", "memory"); 	return (old & mask) != 0;} static __inline__ int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old, t;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__(	EIEIO_ON_SMP"1:	ldarx	%0,0,%3		# test_and_clear_bit\n\	andc	%1,%0,%2\n\	stdcx.	%1,0,%3\n\	bne-	1b"	ISYNC_ON_SMP	: "=&r" (old), "=&r" (t)	: "r" (mask), "r" (p)	: "cc", "memory"); 	return (old & mask) != 0;} static __inline__ int test_and_change_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long old, t;	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	__asm__ __volatile__(	EIEIO_ON_SMP"1:	ldarx	%0,0,%3		# test_and_change_bit\n\	xor	%1,%0,%2\n\	stdcx.	%1,0,%3\n\	bne-	1b"	ISYNC_ON_SMP	: "=&r" (old), "=&r" (t)	: "r" (mask), "r" (p)	: "cc", "memory"); 	return (old & mask) != 0;} static __inline__ void set_bits(unsigned long mask, unsigned long *addr){	unsigned long old; 	__asm__ __volatile__("1:	ldarx	%0,0,%3		# set_bit\n\	or	%0,%0,%2\n\	stdcx.	%0,0,%3\n\	bne-	1b"	: "=&r" (old), "=m" (*addr)	: "r" (mask), "r" (addr), "m" (*addr)	: "cc");} /* * non-atomic versions */static __inline__ void __set_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	*p |= mask;} static __inline__ void __clear_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	*p &= ~mask;} static __inline__ void __change_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6); 	*p ^= mask;} static __inline__ int __test_and_set_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);	unsigned long old = *p; 	*p = old | mask;	return (old & mask) != 0;} static __inline__ int __test_and_clear_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);	unsigned long old = *p; 	*p = old & ~mask;	return (old & mask) != 0;} static __inline__ int __test_and_change_bit(unsigned long nr, volatile unsigned long *addr){	unsigned long mask = 1UL << (nr & 0x3f);	unsigned long *p = ((unsigned long *)addr) + (nr >> 6);	unsigned long old = *p; 	*p = old ^ mask;	return (old & mask) != 0;} /* * Return the zero-based bit position (from RIGHT TO LEFT, 63 -> 0) of the * most significant (left-most) 1-bit in a double word. */static __inline__ int __ilog2(unsigned long x){	int lz; 	asm ("cntlzd %0,%1" : "=r" (lz) : "r" (x));	return 63 - lz;} /* * Determines the bit position of the least significant (rightmost) 0 bit * in the specified double word. The returned bit position will be zero-based, * starting from the right side (63 - 0). */static __inline__ unsigned long ffz(unsigned long x){	/* no zero exists anywhere in the 8 byte area. */	if ((x = ~x) == 0)		return 64; 	/*	 * Calculate the bit position of the least signficant '1' bit in x	 * (since x has been changed this will actually be the least signficant	 * '0' bit in * the original x).  Note: (x & -x) gives us a mask that	 * is the least significant * (RIGHT-most) 1-bit of the value in x.	 */	return __ilog2(x & -x);} static __inline__ int __ffs(unsigned long x){	return __ilog2(x & -x);} /* * 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). */static __inline__ int ffs(int x){	unsigned long i = (unsigned long)x;	return __ilog2(i & -i) + 1;} /* * fls: find last (most-significant) bit set. * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. */#define fls(x) generic_fls(x) /* * hweightN: returns the hamming weight (i.e. the number * of bits set) of a N-bit word */#define hweight64(x) generic_hweight64(x)#define hweight32(x) generic_hweight32(x)#define hweight16(x) generic_hweight16(x)#define hweight8(x) generic_hweight8(x) extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, unsigned long offset);#define find_first_zero_bit(addr, size) \	find_next_zero_bit((addr), (size), 0) extern unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset);#define find_first_bit(addr, size) \	find_next_bit((addr), (size), 0) extern unsigned long find_next_zero_le_bit(const unsigned long *addr, unsigned long size, unsigned long offset);#define find_first_zero_le_bit(addr, size) \	find_next_zero_le_bit((addr), (size), 0) static __inline__ int test_le_bit(unsigned long nr, __const__ unsigned long * addr){	__const__ unsigned char	*ADDR = (__const__ unsigned char *) addr;	return (ADDR[nr >> 3] >> (nr & 7)) & 1;} #define test_and_clear_le_bit(nr, addr) \	test_and_clear_bit((nr) ^ 0x38, (addr))#define test_and_set_le_bit(nr, addr) \	test_and_set_bit((nr) ^ 0x38, (addr)) /* * non-atomic versions */ #define __set_le_bit(nr, addr) \	__set_bit((nr) ^ 0x38, (addr))#define __clear_le_bit(nr, addr) \	__clear_bit((nr) ^ 0x38, (addr))#define __test_and_clear_le_bit(nr, addr) \	__test_and_clear_bit((nr) ^ 0x38, (addr))#define __test_and_set_le_bit(nr, addr) \	__test_and_set_bit((nr) ^ 0x38, (addr)) #define ext2_set_bit(nr,addr) \	__test_and_set_le_bit((nr), (unsigned long*)addr)#define ext2_clear_bit(nr, addr) \	__test_and_clear_le_bit((nr), (unsigned long*)addr) #define ext2_set_bit_atomic(lock, nr, addr) \	test_and_set_le_bit((nr), (unsigned long*)addr)#define ext2_clear_bit_atomic(lock, nr, addr) \	test_and_clear_le_bit((nr), (unsigned long*)addr)  #define ext2_test_bit(nr, addr)      test_le_bit((nr),(unsigned long*)addr)#define ext2_find_first_zero_bit(addr, size) \	find_first_zero_le_bit((unsigned long*)addr, size)#define ext2_find_next_zero_bit(addr, size, off) \	find_next_zero_le_bit((unsigned long*)addr, size, off) #define minix_test_and_set_bit(nr,addr)		test_and_set_bit(nr,addr)#define minix_set_bit(nr,addr)			set_bit(nr,addr)#define minix_test_and_clear_bit(nr,addr)	test_and_clear_bit(nr,addr)#define minix_test_bit(nr,addr)			test_bit(nr,addr)#define minix_find_first_zero_bit(addr,size)	find_first_zero_bit(addr,size) #endif /* __KERNEL__ */#endif /* _PPC64_BITOPS_H */