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#ifndef __BITOPS_H__
#define __BITOPS_H__
/*
* Non-atomic bitops.
*/
#include <stdbool.h>
#define BITS_PER_LONG __LONG_WIDTH__
#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_LONG)
#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
static inline void __set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p |= mask;
}
static inline void set_bit(int nr, volatile unsigned long *addr)
{
__set_bit(nr, addr);
}
static inline void __clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p &= ~mask;
}
static inline void clear_bit(int nr, volatile unsigned long *addr)
{
__clear_bit(nr, addr);
}
static inline bool test_bit(int nr, const volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
return (*p & mask) != 0;
}
/* Sets and returns original value of the bit */
static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
{
if (test_bit(nr, addr))
return 1;
set_bit(nr, addr);
return 0;
}
/**
* fls - find last (most-significant) bit set
* @x: the word to search
*
* This is defined the same way as ffs.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static inline int fls(int x)
{
int r = 32;
if (!x)
return 0;
if (!(x & 0xffff0000u)) {
x <<= 16;
r -= 16;
}
if (!(x & 0xff000000u)) {
x <<= 8;
r -= 8;
}
if (!(x & 0xf0000000u)) {
x <<= 4;
r -= 4;
}
if (!(x & 0xc0000000u)) {
x <<= 2;
r -= 2;
}
if (!(x & 0x80000000u)) {
x <<= 1;
r -= 1;
}
return r;
}
/**
* __ffs - find first bit in word.
* @word: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static inline unsigned long __ffs(unsigned long word)
{
int num = 0;
#if BITS_PER_LONG == 64
if ((word & 0xffffffff) == 0) {
num += 32;
word >>= 32;
}
#endif
if ((word & 0xffff) == 0) {
num += 16;
word >>= 16;
}
if ((word & 0xff) == 0) {
num += 8;
word >>= 8;
}
if ((word & 0xf) == 0) {
num += 4;
word >>= 4;
}
if ((word & 0x3) == 0) {
num += 2;
word >>= 2;
}
if ((word & 0x1) == 0)
num += 1;
return num;
}
unsigned long _find_next_bit(const unsigned long *addr,
unsigned long nbits, unsigned long start, unsigned long invert);
/*
* Find the next set bit in a memory region.
*/
static inline unsigned long find_next_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
return _find_next_bit(addr, size, offset, 0UL);
}
static inline unsigned long find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
return _find_next_bit(addr, size, offset, ~0UL);
}
#endif
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