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/*
* 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_ARM_BITOPS_H
#define __ASM_ARM_BITOPS_H
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <linux/bitops.h>
#endif
#include <asm/proc-armv/system.h>
#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, volatile void * addr);
extern void clear_bit(int nr, volatile void * addr);
extern void change_bit(int nr, volatile void * addr);
static inline void __change_bit(int nr, volatile 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, volatile 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, volatile void * addr)
{
unsigned long flags = 0;
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, volatile 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, volatile void * addr)
{
unsigned long flags = 0;
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, volatile void * addr);
static inline int __test_and_change_bit(int nr, volatile 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;
}
/*
* 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));
}
static inline int __ilog2(unsigned int x)
{
return generic_fls(x) - 1;
}
#define ffz(x) __ffs(~(x))
static inline int find_next_zero_bit(void *addr, int size, int offset)
{
unsigned long *p = ((unsigned long *)addr) + (offset / BITS_PER_LONG);
unsigned long result = offset & ~(BITS_PER_LONG - 1);
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= (BITS_PER_LONG - 1);
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (BITS_PER_LONG - offset);
if (size < BITS_PER_LONG)
goto found_first;
if (~tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG - 1)) {
tmp = *(p++);
if (~tmp)
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
found_middle:
return result + ffz(tmp);
}
/*
* 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 find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
#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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