alistair23-linux/include/asm-sh64/bitops.h
Akinobu Mita 67b0ad574b [PATCH] bitops: use non atomic operations for minix_*_bit() and ext2_*_bit()
Bitmap functions for the minix filesystem and the ext2 filesystem except
ext2_set_bit_atomic() and ext2_clear_bit_atomic() do not require the atomic
guarantees.

But these are defined by using atomic bit operations on several architectures.
 (cris, frv, h8300, ia64, m32r, m68k, m68knommu, mips, s390, sh, sh64, sparc,
sparc64, v850, and xtensa)

This patch switches to non atomic bit operation.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:10 -08:00

512 lines
11 KiB
C

#ifndef __ASM_SH64_BITOPS_H
#define __ASM_SH64_BITOPS_H
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* include/asm-sh64/bitops.h
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 Paul Mundt
*/
#ifdef __KERNEL__
#include <linux/compiler.h>
#include <asm/system.h>
/* For __swab32 */
#include <asm/byteorder.h>
static __inline__ void set_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a |= mask;
local_irq_restore(flags);
}
static inline void __set_bit(int nr, void *addr)
{
int mask;
unsigned int *a = addr;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
*a |= mask;
}
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
static inline void clear_bit(int nr, volatile unsigned long *a)
{
int mask;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a &= ~mask;
local_irq_restore(flags);
}
static inline void __clear_bit(int nr, volatile unsigned long *a)
{
int mask;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
*a &= ~mask;
}
static __inline__ void change_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a ^= mask;
local_irq_restore(flags);
}
static __inline__ void __change_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
*a ^= mask;
}
static __inline__ int test_and_set_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a |= mask;
local_irq_restore(flags);
return retval;
}
static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
retval = (mask & *a) != 0;
*a |= mask;
return retval;
}
static __inline__ int test_and_clear_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a &= ~mask;
local_irq_restore(flags);
return retval;
}
static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
retval = (mask & *a) != 0;
*a &= ~mask;
return retval;
}
static __inline__ int test_and_change_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a ^= mask;
local_irq_restore(flags);
return retval;
}
static __inline__ int __test_and_change_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
retval = (mask & *a) != 0;
*a ^= mask;
return retval;
}
static __inline__ int test_bit(int nr, const volatile void *addr)
{
return 1UL & (((const volatile unsigned int *) addr)[nr >> 5] >> (nr & 31));
}
static __inline__ unsigned long ffz(unsigned long word)
{
unsigned long result, __d2, __d3;
__asm__("gettr tr0, %2\n\t"
"pta $+32, tr0\n\t"
"andi %1, 1, %3\n\t"
"beq %3, r63, tr0\n\t"
"pta $+4, tr0\n"
"0:\n\t"
"shlri.l %1, 1, %1\n\t"
"addi %0, 1, %0\n\t"
"andi %1, 1, %3\n\t"
"beqi %3, 1, tr0\n"
"1:\n\t"
"ptabs %2, tr0\n\t"
: "=r" (result), "=r" (word), "=r" (__d2), "=r" (__d3)
: "0" (0L), "1" (word));
return result;
}
/**
* __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 r = 0;
if (!word)
return 0;
if (!(word & 0xffff)) {
word >>= 16;
r += 16;
}
if (!(word & 0xff)) {
word >>= 8;
r += 8;
}
if (!(word & 0xf)) {
word >>= 4;
r += 4;
}
if (!(word & 3)) {
word >>= 2;
r += 2;
}
if (!(word & 1)) {
word >>= 1;
r += 1;
}
return r;
}
/**
* find_next_bit - find the next set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
static inline unsigned long find_next_bit(const unsigned long *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 << offset;
if (size < 32)
goto found_first;
if (tmp)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = *p++) != 0)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= ~0UL >> (32 - size);
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found_middle:
return result + __ffs(tmp);
}
/**
* find_first_bit - find the first set bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit-number of the first set bit, not the number of the byte
* containing a bit.
*/
#define find_first_bit(addr, size) \
find_next_bit((addr), (size), 0)
static inline int find_next_zero_bit(void *addr, int size, int offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
unsigned long result = offset & ~31UL;
unsigned long 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)
goto found_middle;
size -= 32;
result += 32;
}
while (size & ~31UL) {
if (~(tmp = *(p++)))
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 find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
/*
* 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)
/*
* Every architecture must define this function. It's the fastest
* way of searching a 140-bit bitmap where the first 100 bits are
* unlikely to be set. It's guaranteed that at least one of the 140
* bits is cleared.
*/
static inline int sched_find_first_bit(unsigned long *b)
{
if (unlikely(b[0]))
return __ffs(b[0]);
if (unlikely(b[1]))
return __ffs(b[1]) + 32;
if (unlikely(b[2]))
return __ffs(b[2]) + 64;
if (b[3])
return __ffs(b[3]) + 96;
return __ffs(b[4]) + 128;
}
/*
* 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).
*/
#define ffs(x) generic_ffs(x)
/*
* 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)
#ifdef __LITTLE_ENDIAN__
#define ext2_set_bit(nr, addr) __test_and_set_bit((nr), (addr))
#define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr), (addr))
#define ext2_test_bit(nr, addr) test_bit((nr), (addr))
#define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr), (size))
#define ext2_find_next_zero_bit(addr, size, offset) \
find_next_zero_bit((addr), (size), (offset))
#else
static __inline__ int ext2_set_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = (mask & *ADDR) != 0;
*ADDR |= mask;
return retval;
}
static __inline__ int ext2_clear_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = (mask & *ADDR) != 0;
*ADDR &= ~mask;
return retval;
}
static __inline__ int ext2_test_bit(int nr, const volatile void * addr)
{
int mask;
const volatile unsigned char *ADDR = (const unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
return ((mask & *ADDR) != 0);
}
#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 long *p = ((unsigned long *) addr) + (offset >> 5);
unsigned long result = offset & ~31UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if(offset) {
/* We hold the little endian value in tmp, but then the
* shift is illegal. So we could keep a big endian value
* in tmp, like this:
*
* tmp = __swab32(*(p++));
* tmp |= ~0UL >> (32-offset);
*
* but this would decrease preformance, so we change the
* shift:
*/
tmp = *(p++);
tmp |= __swab32(~0UL >> (32-offset));
if(size < 32)
goto found_first;
if(~tmp)
goto found_middle;
size -= 32;
result += 32;
}
while(size & ~31UL) {
if(~(tmp = *(p++)))
goto found_middle;
result += 32;
size -= 32;
}
if(!size)
return result;
tmp = *p;
found_first:
/* tmp is little endian, so we would have to swab the shift,
* see above. But then we have to swab tmp below for ffz, so
* we might as well do this here.
*/
return result + ffz(__swab32(tmp) | (~0UL << size));
found_middle:
return result + ffz(__swab32(tmp));
}
#endif
#define ext2_set_bit_atomic(lock, nr, addr) \
({ \
int ret; \
spin_lock(lock); \
ret = ext2_set_bit((nr), (addr)); \
spin_unlock(lock); \
ret; \
})
#define ext2_clear_bit_atomic(lock, nr, addr) \
({ \
int ret; \
spin_lock(lock); \
ret = ext2_clear_bit((nr), (addr)); \
spin_unlock(lock); \
ret; \
})
/* 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)
#define ffs(x) generic_ffs(x)
#define fls(x) generic_fls(x)
#define fls64(x) generic_fls64(x)
#endif /* __KERNEL__ */
#endif /* __ASM_SH64_BITOPS_H */