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/*
* 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.
*
* Copyright (c) 1994, 95, 96, 97, 98, 99, 2000 Ralf Baechle
* Copyright (c) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#include <linux/types.h>
#include <linux/byteorder/swab.h> /* sigh ... */
#ifndef __KERNEL__
#error "Don't do this, sucker ..."
#endif
#include <asm/system.h>
#include <asm/sgidefs.h>
#include <asm/mipsregs.h>
/*
* set_bit - Atomically set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* This function is atomic and may not be reordered. See __set_bit()
* if you do not require the atomic guarantees.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
extern __inline__ void
set_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp;
__asm__ __volatile__(
"1:\tlld\t%0, %1\t\t# set_bit\n\t"
"or\t%0, %2\n\t"
"scd\t%0, %1\n\t"
"beqz\t%0, 1b"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << (nr & 0x3f)), "m" (*m)
: "memory");
}
/*
* __set_bit - Set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* Unlike set_bit(), this function is non-atomic and may be reordered.
* If it's called on the same region of memory simultaneously, the effect
* may be that only one operation succeeds.
*/
extern __inline__ void __set_bit(int nr, volatile void * addr)
{
unsigned long * m = ((unsigned long *) addr) + (nr >> 6);
*m |= 1UL << (nr & 0x3f);
}
/*
* clear_bit - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit() is atomic and may not be reordered. However, it does
* not contain a memory barrier, so if it is used for locking purposes,
* you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
* in order to ensure changes are visible on other processors.
*/
extern __inline__ void
clear_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp;
__asm__ __volatile__(
"1:\tlld\t%0, %1\t\t# clear_bit\n\t"
"and\t%0, %2\n\t"
"scd\t%0, %1\n\t"
"beqz\t%0, 1b\n\t"
: "=&r" (temp), "=m" (*m)
: "ir" (~(1UL << (nr & 0x3f))), "m" (*m));
}
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
/*
* change_bit - Toggle a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* change_bit() is atomic and may not be reordered.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
extern __inline__ void
change_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp;
__asm__ __volatile__(
"1:\tlld\t%0, %1\t\t# change_bit\n\t"
"xor\t%0, %2\n\t"
"scd\t%0, %1\n\t"
"beqz\t%0, 1b"
:"=&r" (temp), "=m" (*m)
:"ir" (1UL << (nr & 0x3f)), "m" (*m));
}
/*
* __change_bit - Toggle a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* Unlike change_bit(), this function is non-atomic and may be reordered.
* If it's called on the same region of memory simultaneously, the effect
* may be that only one operation succeeds.
*/
extern __inline__ void __change_bit(int nr, volatile void * addr)
{
unsigned long * m = ((unsigned long *) addr) + (nr >> 6);
*m ^= 1UL << (nr & 0x3f);
}
/*
* test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
extern __inline__ unsigned long
test_and_set_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp, res;
__asm__ __volatile__(
".set\tnoreorder\t\t# test_and_set_bit\n"
"1:\tlld\t%0, %1\n\t"
"or\t%2, %0, %3\n\t"
"scd\t%2, %1\n\t"
"beqz\t%2, 1b\n\t"
" and\t%2, %0, %3\n\t"
".set\treorder"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & 0x3f)), "m" (*m)
: "memory");
return res != 0;
}
/*
* __test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is non-atomic and can be reordered.
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
extern __inline__ int
__test_and_set_bit(int nr, volatile void * addr)
{
unsigned long mask, retval;
long *a = (unsigned long *) addr;
a += (nr >> 6);
mask = 1UL << (nr & 0x3f);
retval = ((mask & *a) != 0);
*a |= mask;
return retval;
}
/*
* test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
extern __inline__ unsigned long
test_and_clear_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp, res;
__asm__ __volatile__(
".set\tnoreorder\t\t# test_and_clear_bit\n"
"1:\tlld\t%0, %1\n\t"
"or\t%2, %0, %3\n\t"
"xor\t%2, %3\n\t"
"scd\t%2, %1\n\t"
"beqz\t%2, 1b\n\t"
" and\t%2, %0, %3\n\t"
".set\treorder"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & 0x3f)), "m" (*m)
: "memory");
return res != 0;
}
/*
* __test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is non-atomic and can be reordered.
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
extern __inline__ int
__test_and_clear_bit(int nr, volatile void * addr)
{
unsigned long mask, retval;
unsigned long *a = (unsigned long *) addr;
a += (nr >> 6);
mask = 1UL << (nr & 0x3f);
retval = ((mask & *a) != 0);
*a &= ~mask;
return retval;
}
/*
* test_and_change_bit - Change a bit and return its new value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
extern __inline__ unsigned long
test_and_change_bit(unsigned long nr, volatile void *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> 6);
unsigned long temp, res;
__asm__ __volatile__(
".set\tnoreorder\t\t# test_and_change_bit\n"
"1:\tlld\t%0, %1\n\t"
"xor\t%2, %0, %3\n\t"
"scd\t%2, %1\n\t"
"beqz\t%2, 1b\n\t"
" and\t%2, %0, %3\n\t"
".set\treorder"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & 0x3f)), "m" (*m)
: "memory");
return res != 0;
}
/*
* __test_and_change_bit - Change a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is non-atomic and can be reordered.
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
extern __inline__ int
__test_and_change_bit(int nr, volatile void * addr)
{
unsigned long mask, retval;
unsigned long *a = (unsigned long *) addr;
a += (nr >> 6);
mask = 1UL << (nr & 0x3f);
retval = ((mask & *a) != 0);
*a ^= mask;
return retval;
}
/*
* test_bit - Determine whether a bit is set
* @nr: bit number to test
* @addr: Address to start counting from
*/
extern __inline__ unsigned long
test_bit(int nr, volatile void * addr)
{
return 1UL & (((volatile unsigned long *) addr)[nr >> 6] >> (nr & 0x3f));
}
#ifndef __MIPSEB__
/* Little endian versions. */
/*
* find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte
* containing a bit.
*/
extern __inline__ int
find_first_zero_bit (void *addr, unsigned size)
{
unsigned long dummy;
int res;
if (!size)
return 0;
__asm__ (".set\tnoreorder\n\t"
".set\tnoat\n"
"1:\tsubu\t$1,%6,%0\n\t"
"blez\t$1,2f\n\t"
"lw\t$1,(%5)\n\t"
"addiu\t%5,4\n\t"
#if (_MIPS_ISA == _MIPS_ISA_MIPS2 ) || (_MIPS_ISA == _MIPS_ISA_MIPS3 ) || \
(_MIPS_ISA == _MIPS_ISA_MIPS4 ) || (_MIPS_ISA == _MIPS_ISA_MIPS5 ) || \
(_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64)
"beql\t%1,$1,1b\n\t"
"addiu\t%0,32\n\t"
#else
"addiu\t%0,32\n\t"
"beq\t%1,$1,1b\n\t"
"nop\n\t"
"subu\t%0,32\n\t"
#endif
"li\t%1,1\n"
"1:\tand\t%2,$1,%1\n\t"
"beqz\t%2,2f\n\t"
"sll\t%1,%1,1\n\t"
"bnez\t%1,1b\n\t"
"add\t%0,%0,1\n\t"
".set\tat\n\t"
".set\treorder\n"
"2:"
: "=r" (res), "=r" (dummy), "=r" (addr)
: "0" ((signed int) 0), "1" ((unsigned int) 0xffffffff),
"2" (addr), "r" (size)
: "$1");
return res;
}
/*
* find_next_zero_bit - find the first zero 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
*/
extern __inline__ int
find_next_zero_bit (void * addr, int size, int offset)
{
unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
int set = 0, bit = offset & 31, res;
unsigned long dummy;
if (bit) {
/*
* Look for zero in first byte
*/
__asm__(".set\tnoreorder\n\t"
".set\tnoat\n"
"1:\tand\t$1,%4,%1\n\t"
"beqz\t$1,1f\n\t"
"sll\t%1,%1,1\n\t"
"bnez\t%1,1b\n\t"
"addiu\t%0,1\n\t"
".set\tat\n\t"
".set\treorder\n"
"1:"
: "=r" (set), "=r" (dummy)
: "0" (0), "1" (1 << bit), "r" (*p)
: "$1");
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No zero yet, search remaining full bytes for a zero
*/
res = find_first_zero_bit(p, size - 32 * (p - (unsigned int *) addr));
return offset + set + res;
}
#endif /* !(__MIPSEB__) */
/*
* ffz - find first zero in word.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
extern __inline__ unsigned long ffz(unsigned long word)
{
unsigned long k;
word = ~word;
k = 63;
if (word & 0x00000000ffffffffUL) { k -= 32; word <<= 32; }
if (word & 0x0000ffff00000000UL) { k -= 16; word <<= 16; }
if (word & 0x00ff000000000000UL) { k -= 8; word <<= 8; }
if (word & 0x0f00000000000000UL) { k -= 4; word <<= 4; }
if (word & 0x3000000000000000UL) { k -= 2; word <<= 2; }
if (word & 0x4000000000000000UL) { k -= 1; }
return k;
}
#ifdef __KERNEL__
/*
* ffs - find first bit set
* @x: the word to search
*
* 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 of a N-bit word
* @x: the word to weigh
*
* The Hamming Weight of a number is the total number of bits set in it.
*/
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
#endif /* __KERNEL__ */
#ifdef __MIPSEB__
/*
* find_next_zero_bit - find the first zero 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
*/
extern __inline__ unsigned long
find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (64-offset);
if (size < 64)
goto found_first;
if (~tmp)
goto found_middle;
size -= 64;
result += 64;
}
while (size & ~63UL) {
if (~(tmp = *(p++)))
goto found_middle;
result += 64;
size -= 64;
}
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)
#endif /* (__MIPSEB__) */
#ifdef __KERNEL__
/* Now for the ext2 filesystem bit operations and helper routines. */
#ifdef __MIPSEB__
extern inline int
ext2_set_bit(int nr,void * addr)
{
int mask, retval, flags;
unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
save_and_cli(flags);
retval = (mask & *ADDR) != 0;
*ADDR |= mask;
restore_flags(flags);
return retval;
}
extern inline int
ext2_clear_bit(int nr, void * addr)
{
int mask, retval, flags;
unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
save_and_cli(flags);
retval = (mask & *ADDR) != 0;
*ADDR &= ~mask;
restore_flags(flags);
return retval;
}
extern inline int
ext2_test_bit(int nr, const void * addr)
{
int mask;
const 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)
extern inline unsigned int
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) {
/* 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));
}
#else /* !(__MIPSEB__) */
/* Native ext2 byte ordering, just collapse using defines. */
#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))
#endif /* !(__MIPSEB__) */
/*
* Bitmap functions for the minix filesystem.
* FIXME: These assume that Minix uses the native byte/bitorder.
* This limits the Minix filesystem's value for data exchange very much.
*/
#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 /* _ASM_BITOPS_H */
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