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/*
* Copyright (c) 2011 The Chromium OS Authors.
*
* Copyright 1995, Russell King.
* Various bits and pieces copyrights include:
* Linus Torvalds (test_bit).
*
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*
* Please note that the code in this file should never be included
* from user space. Many of these are not implemented in assembler
* since they would be too costly. Also, they require priviledged
* instructions (which are not available from user mode) to ensure
* that they are atomic.
*/
#ifndef __ASM_SANDBOX_BITOPS_H
#define __ASM_SANDBOX_BITOPS_H
#include <asm/system.h>
#ifdef __KERNEL__
#define smp_mb__before_clear_bit() do { } while (0)
#define smp_mb__after_clear_bit() do { } while (0)
/*
* Function prototypes to keep gcc -Wall happy.
*/
extern void set_bit(int nr, void *addr);
extern void clear_bit(int nr, void *addr);
extern void change_bit(int nr, void *addr);
static inline void __change_bit(int nr, void *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, void *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_set_bit(int nr, void *addr)
{
unsigned long flags;
int out;
local_irq_save(flags);
out = __test_and_set_bit(nr, addr);
local_irq_restore(flags);
return out;
}
static inline int __test_and_clear_bit(int nr, void *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, void *addr)
{
unsigned long flags;
int out;
local_irq_save(flags);
out = __test_and_clear_bit(nr, addr);
local_irq_restore(flags);
return out;
}
extern int test_and_change_bit(int nr, void *addr);
static inline int __test_and_change_bit(int nr, void *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;
}
extern int find_first_zero_bit(void *addr, unsigned size);
extern int find_next_zero_bit(void *addr, int size, int offset);
/*
* This routine doesn't need to be atomic.
*/
static inline int test_bit(int nr, const void *addr)
{
return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7));
}
/*
* ffz = Find First Zero in word. Undefined if no zero exists,
* so code should check against ~0UL first..
*/
static inline unsigned long ffz(unsigned long word)
{
int k;
word = ~word;
k = 31;
if (word & 0x0000ffff) {
k -= 16; word <<= 16;
}
if (word & 0x00ff0000) {
k -= 8; word <<= 8;
}
if (word & 0x0f000000) {
k -= 4; word <<= 4;
}
if (word & 0x30000000) {
k -= 2; word <<= 2;
}
if (word & 0x40000000)
k -= 1;
return k;
}
/*
* 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)
#define ext2_set_bit test_and_set_bit
#define ext2_clear_bit test_and_clear_bit
#define ext2_test_bit test_bit
#define ext2_find_first_zero_bit find_first_zero_bit
#define ext2_find_next_zero_bit find_next_zero_bit
/* Bitmap functions for the minix filesystem. */
#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 /* _ARM_BITOPS_H */
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