388 lines
8.5 KiB
C
388 lines
8.5 KiB
C
/*
|
|
* bitops.h: Bit string operations on the ppc
|
|
*/
|
|
|
|
#ifndef _PPC_BITOPS_H
|
|
#define _PPC_BITOPS_H
|
|
|
|
#include <linux/config.h>
|
|
#include <asm/byteorder.h>
|
|
|
|
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);
|
|
extern int test_and_set_bit(int nr, volatile void *addr);
|
|
extern int test_and_clear_bit(int nr, volatile void *addr);
|
|
extern int test_and_change_bit(int nr, volatile void *addr);
|
|
|
|
/*
|
|
* Arguably these bit operations don't imply any memory barrier or
|
|
* SMP ordering, but in fact a lot of drivers expect them to imply
|
|
* both, since they do on x86 cpus.
|
|
*/
|
|
#ifdef CONFIG_SMP
|
|
#define SMP_WMB "eieio\n"
|
|
#define SMP_MB "\nsync"
|
|
#else
|
|
#define SMP_WMB
|
|
#define SMP_MB
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#define __INLINE_BITOPS 1
|
|
|
|
#if __INLINE_BITOPS
|
|
/*
|
|
* These used to be if'd out here because using : "cc" as a constraint
|
|
* resulted in errors from egcs. Things may be OK with gcc-2.95.
|
|
*/
|
|
extern __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__(SMP_WMB "\
|
|
1: lwarx %0,0,%3\n\
|
|
or %0,%0,%2\n\
|
|
stwcx. %0,0,%3\n\
|
|
bne 1b"
|
|
SMP_MB
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc" );
|
|
}
|
|
|
|
extern __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__(SMP_WMB "\
|
|
1: lwarx %0,0,%3\n\
|
|
andc %0,%0,%2\n\
|
|
stwcx. %0,0,%3\n\
|
|
bne 1b"
|
|
SMP_MB
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc");
|
|
}
|
|
|
|
extern __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__(SMP_WMB "\
|
|
1: lwarx %0,0,%3\n\
|
|
xor %0,%0,%2\n\
|
|
stwcx. %0,0,%3\n\
|
|
bne 1b"
|
|
SMP_MB
|
|
: "=&r" (old), "=m" (*p)
|
|
: "r" (mask), "r" (p), "m" (*p)
|
|
: "cc");
|
|
}
|
|
|
|
extern __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 "\
|
|
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");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
extern __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 "\
|
|
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");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
|
|
extern __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 "\
|
|
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");
|
|
|
|
return (old & mask) != 0;
|
|
}
|
|
#endif /* __INLINE_BITOPS */
|
|
|
|
extern __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 */
|
|
/* - the result is undefined when x == 0 */
|
|
extern __inline__ int __ilog2(unsigned int x)
|
|
{
|
|
int lz;
|
|
|
|
asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
|
|
return 31 - lz;
|
|
}
|
|
|
|
extern __inline__ int ffz(unsigned int x)
|
|
{
|
|
if ((x = ~x) == 0)
|
|
return 32;
|
|
return __ilog2(x & -x);
|
|
}
|
|
|
|
/*
|
|
* fls: find last (most-significant) bit set.
|
|
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
|
|
*
|
|
* On powerpc, __ilog2(0) returns -1, but this is not safe in general
|
|
*/
|
|
static __inline__ int fls(unsigned int x)
|
|
{
|
|
return __ilog2(x) + 1;
|
|
}
|
|
#define PLATFORM_FLS
|
|
|
|
/**
|
|
* fls64 - find last set bit in a 64-bit word
|
|
* @x: the word to search
|
|
*
|
|
* This is defined in a similar way as the libc and compiler builtin
|
|
* ffsll, but returns the position of the most significant set bit.
|
|
*
|
|
* fls64(value) returns 0 if value is 0 or the position of the last
|
|
* set bit if value is nonzero. The last (most significant) bit is
|
|
* at position 64.
|
|
*/
|
|
#if BITS_PER_LONG == 32
|
|
static inline int fls64(__u64 x)
|
|
{
|
|
__u32 h = x >> 32;
|
|
if (h)
|
|
return fls(h) + 32;
|
|
return fls(x);
|
|
}
|
|
#elif BITS_PER_LONG == 64
|
|
static inline int fls64(__u64 x)
|
|
{
|
|
if (x == 0)
|
|
return 0;
|
|
return __ilog2(x) + 1;
|
|
}
|
|
#else
|
|
#error BITS_PER_LONG not 32 or 64
|
|
#endif
|
|
|
|
static inline int __ilog2_u64(u64 n)
|
|
{
|
|
return fls64(n) - 1;
|
|
}
|
|
|
|
static inline int ffs64(u64 x)
|
|
{
|
|
return __ilog2_u64(x & -x) + 1ull;
|
|
}
|
|
|
|
#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).
|
|
*/
|
|
extern __inline__ int ffs(int x)
|
|
{
|
|
return __ilog2(x & -x) + 1;
|
|
}
|
|
#define PLATFORM_FFS
|
|
|
|
/*
|
|
* 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)
|
|
|
|
extern __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;
|
|
found_middle:
|
|
return result + ffz(tmp);
|
|
}
|
|
|
|
|
|
#define _EXT2_HAVE_ASM_BITOPS_
|
|
|
|
#ifdef __KERNEL__
|
|
/*
|
|
* test_and_{set,clear}_bit guarantee atomicity without
|
|
* disabling interrupts.
|
|
*/
|
|
#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)
|
|
|
|
#else
|
|
extern __inline__ int ext2_set_bit(int nr, void * addr)
|
|
{
|
|
int mask;
|
|
unsigned char *ADDR = (unsigned char *) addr;
|
|
int oldbit;
|
|
|
|
ADDR += nr >> 3;
|
|
mask = 1 << (nr & 0x07);
|
|
oldbit = (*ADDR & mask) ? 1 : 0;
|
|
*ADDR |= mask;
|
|
return oldbit;
|
|
}
|
|
|
|
extern __inline__ int ext2_clear_bit(int nr, void * addr)
|
|
{
|
|
int mask;
|
|
unsigned char *ADDR = (unsigned char *) addr;
|
|
int oldbit;
|
|
|
|
ADDR += nr >> 3;
|
|
mask = 1 << (nr & 0x07);
|
|
oldbit = (*ADDR & mask) ? 1 : 0;
|
|
*ADDR = *ADDR & ~mask;
|
|
return oldbit;
|
|
}
|
|
#endif /* __KERNEL__ */
|
|
|
|
extern __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;
|
|
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 /* _PPC_BITOPS_H */
|