Viewing file:  bitops.h (8.25 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* BK Id: SCCS/s.bitops.h 1.9 05/26/01 14:48:14 paulus
*/
/*
* bitops.h: Bit string operations on the ppc
*/
#ifdef __KERNEL__
#ifndef _PPC_BITOPS_H
#define _PPC_BITOPS_H
#include <linux/config.h>
#include <asm/byteorder.h>
/*
* The test_and_*_bit operations are taken to imply a memory barrier
* on SMP systems.
*/
#ifdef CONFIG_SMP
#define SMP_WMB "eieio\n"
#define SMP_MB "\nsync"
#else
#define SMP_WMB
#define SMP_MB
#endif /* CONFIG_SMP */
/*
* These used to be if'd out here because using : "cc" as a constraint
* resulted in errors from egcs. Things appear to be OK with gcc-2.95.
*/
static __inline__ void set_bit(int nr, volatile void * addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
or %0,%0,%2 \n\
stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc" );
}
/*
* non-atomic version
*/
static __inline__ void __set_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p |= mask;
}
/*
* 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__ void clear_bit(int nr, volatile void *addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
andc %0,%0,%2 \n\
stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc");
}
/*
* non-atomic version
*/
static __inline__ void __clear_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p &= ~mask;
}
static __inline__ void change_bit(int nr, volatile void *addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
xor %0,%0,%2 \n\
stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc");
}
/*
* non-atomic version
*/
static __inline__ void __change_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p ^= mask;
}
/*
* test_and_*_bit do imply a memory barrier (?)
*/
static __inline__ int test_and_set_bit(int nr, volatile void *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
or %1,%0,%3 \n\
stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_set_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old | mask;
return (old & mask) != 0;
}
static __inline__ int test_and_clear_bit(int nr, volatile void *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
andc %1,%0,%3 \n\
stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_clear_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old & ~mask;
return (old & mask) != 0;
}
static __inline__ int test_and_change_bit(int nr, volatile void *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
xor %1,%0,%3 \n\
stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_change_bit(int nr, volatile void *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old ^ mask;
return (old & mask) != 0;
}
static __inline__ int test_bit(int nr, __const__ volatile void *addr)
{
__const__ unsigned int *p = (__const__ unsigned int *) addr;
return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
}
/* Return the bit position of the most significant 1 bit in a word */
static __inline__ int __ilog2(unsigned int x)
{
int lz;
asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
return 31 - lz;
}
static __inline__ int ffz(unsigned int x)
{
if ((x = ~x) == 0)
return 32;
return __ilog2(x & -x);
}
#ifdef __KERNEL__
/*
* 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)
{
return __ilog2(x & -x) + 1;
}
/*
* 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)
#endif /* __KERNEL__ */
/*
* This implementation of find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h.
*/
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
static __inline__ unsigned long find_next_zero_bit(void * addr,
unsigned long size, unsigned long offset)
{
unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
unsigned int result = offset & ~31UL;
unsigned int tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if (offset) {
tmp = *p++;
tmp |= ~0UL >> (32-offset);
if (size < 32)
goto found_first;
if (tmp != ~0U)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = *p++) != ~0U)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
#ifdef __KERNEL__
#define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x18, addr)
#define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 0x18, addr)
static __inline__ int ext2_test_bit(int nr, __const__ void * addr)
{
__const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
return (ADDR[nr >> 3] >> (nr & 7)) & 1;
}
/*
* This implementation of ext2_find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h and modified for a big-endian machine.
*/
#define ext2_find_first_zero_bit(addr, size) \
ext2_find_next_zero_bit((addr), (size), 0)
static __inline__ unsigned long ext2_find_next_zero_bit(void *addr,
unsigned long size, unsigned long offset)
{
unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
unsigned int result = offset & ~31UL;
unsigned int tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if (offset) {
tmp = cpu_to_le32p(p++);
tmp |= ~0UL >> (32-offset);
if (size < 32)
goto found_first;
if (tmp != ~0U)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = cpu_to_le32p(p++)) != ~0U)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = cpu_to_le32p(p);
found_first:
tmp |= ~0U << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
/* Bitmap functions for the minix filesystem. */
#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
#define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr))
#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
#endif /* __KERNEL__ */
#endif /* _PPC_BITOPS_H */
#endif /* __KERNEL__ */
|