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linux/include/asm-mips/bitops.h
Ralf Baechle 2caf190002 [MIPS] Cleanup fls implementation. 
fls was the only called of flz, so fold flz into fls, same for the
__ilog2 call.  Delete the now unused flz function.
    
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-02-07 13:30:24 +00:00

974 lines
24 KiB
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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 - 1997, 1999, 2000 Ralf Baechle (ralf@gnu.org)
* Copyright (c) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/bug.h>
#include <asm/byteorder.h> /* sigh ... */
#include <asm/cpu-features.h>
#if (_MIPS_SZLONG == 32)
#define SZLONG_LOG 5
#define SZLONG_MASK 31UL
#define __LL "ll "
#define __SC "sc "
#define cpu_to_lelongp(x) cpu_to_le32p((__u32 *) (x))
#elif (_MIPS_SZLONG == 64)
#define SZLONG_LOG 6
#define SZLONG_MASK 63UL
#define __LL "lld "
#define __SC "scd "
#define cpu_to_lelongp(x) cpu_to_le64p((__u64 *) (x))
#endif
#ifdef __KERNEL__
#include <asm/interrupt.h>
#include <asm/sgidefs.h>
#include <asm/war.h>
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() smp_mb()
/*
* Only disable interrupt for kernel mode stuff to keep usermode stuff
* that dares to use kernel include files alive.
*/
#define __bi_flags unsigned long flags
#define __bi_local_irq_save(x) local_irq_save(x)
#define __bi_local_irq_restore(x) local_irq_restore(x)
#else
#define __bi_flags
#define __bi_local_irq_save(x)
#define __bi_local_irq_restore(x)
#endif /* __KERNEL__ */
/*
* 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.
*/
static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
if (cpu_has_llsc && R10000_LLSC_WAR) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # set_bit \n"
" or %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
} else if (cpu_has_llsc) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # set_bit \n"
" or %0, %2 \n"
" " __SC "%0, %1 \n"
" beqz %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
*a |= mask;
__bi_local_irq_restore(flags);
}
}
/*
* __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.
*/
static inline void __set_bit(unsigned long nr, volatile unsigned long * addr)
{
unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
*m |= 1UL << (nr & SZLONG_MASK);
}
/*
* 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.
*/
static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
if (cpu_has_llsc && R10000_LLSC_WAR) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # clear_bit \n"
" and %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
} else if (cpu_has_llsc) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # clear_bit \n"
" and %0, %2 \n"
" " __SC "%0, %1 \n"
" beqz %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
*a &= ~mask;
__bi_local_irq_restore(flags);
}
}
/*
* __clear_bit - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* Unlike clear_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.
*/
static inline void __clear_bit(unsigned long nr, volatile unsigned long * addr)
{
unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
*m &= ~(1UL << (nr & SZLONG_MASK));
}
/*
* change_bit - Toggle a bit in memory
* @nr: Bit to change
* @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.
*/
static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
{
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # change_bit \n"
" xor %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
} else if (cpu_has_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # change_bit \n"
" xor %0, %2 \n"
" " __SC "%0, %1 \n"
" beqz %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
*a ^= mask;
__bi_local_irq_restore(flags);
}
}
/*
* __change_bit - Toggle a bit in memory
* @nr: the bit to change
* @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.
*/
static inline void __change_bit(unsigned long nr, volatile unsigned long * addr)
{
unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
*m ^= 1UL << (nr & SZLONG_MASK);
}
/*
* 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.
*/
static inline int test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set mips0 \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else if (cpu_has_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set push \n"
" .set noreorder \n"
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqz %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set pop \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else {
volatile unsigned long *a = addr;
unsigned long mask;
int retval;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
retval = (mask & *a) != 0;
*a |= mask;
__bi_local_irq_restore(flags);
return retval;
}
}
/*
* __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.
*/
static inline int __test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
volatile unsigned long *a = addr;
unsigned long mask;
int retval;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
retval = (mask & *a) != 0;
*a |= mask;
return retval;
}
/*
* test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_clear_bit(unsigned long nr,
volatile unsigned long *addr)
{
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_clear_bit \n"
" or %2, %0, %3 \n"
" xor %2, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set mips0 \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else if (cpu_has_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set push \n"
" .set noreorder \n"
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_clear_bit \n"
" or %2, %0, %3 \n"
" xor %2, %3 \n"
" " __SC "%2, %1 \n"
" beqz %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set pop \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else {
volatile unsigned long *a = addr;
unsigned long mask;
int retval;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
retval = (mask & *a) != 0;
*a &= ~mask;
__bi_local_irq_restore(flags);
return retval;
}
}
/*
* __test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @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.
*/
static inline int __test_and_clear_bit(unsigned long nr,
volatile unsigned long * addr)
{
volatile unsigned long *a = addr;
unsigned long mask;
int retval;
a += (nr >> SZLONG_LOG);
mask = 1UL << (nr & SZLONG_MASK);
retval = ((mask & *a) != 0);
*a &= ~mask;
return retval;
}
/*
* test_and_change_bit - Change a bit and return its old value
* @nr: Bit to change
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_change_bit(unsigned long nr,
volatile unsigned long *addr)
{
if (cpu_has_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_change_bit \n"
" xor %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set mips0 \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else if (cpu_has_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp, res;
__asm__ __volatile__(
" .set push \n"
" .set noreorder \n"
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_change_bit \n"
" xor %2, %0, %3 \n"
" " __SC "\t%2, %1 \n"
" beqz %2, 1b \n"
" and %2, %0, %3 \n"
#ifdef CONFIG_SMP
" sync \n"
#endif
" .set pop \n"
: "=&r" (temp), "=m" (*m), "=&r" (res)
: "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
: "memory");
return res != 0;
} else {
volatile unsigned long *a = addr;
unsigned long mask, retval;
__bi_flags;
a += nr >> SZLONG_LOG;
mask = 1UL << (nr & SZLONG_MASK);
__bi_local_irq_save(flags);
retval = (mask & *a) != 0;
*a ^= mask;
__bi_local_irq_restore(flags);
return retval;
}
}
/*
* __test_and_change_bit - Change a bit and return its old value
* @nr: Bit to change
* @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.
*/
static inline int __test_and_change_bit(unsigned long nr,
volatile unsigned long *addr)
{
volatile unsigned long *a = addr;
unsigned long mask;
int retval;
a += (nr >> SZLONG_LOG);
mask = 1UL << (nr & SZLONG_MASK);
retval = ((mask & *a) != 0);
*a ^= mask;
return retval;
}
#undef __bi_flags
#undef __bi_local_irq_save
#undef __bi_local_irq_restore
/*
* test_bit - Determine whether a bit is set
* @nr: bit number to test
* @addr: Address to start counting from
*/
static inline int test_bit(unsigned long nr, const volatile unsigned long *addr)
{
return 1UL & (addr[nr >> SZLONG_LOG] >> (nr & SZLONG_MASK));
}
/*
* Return the bit position (0..63) of the most significant 1 bit in a word
* Returns -1 if no 1 bit exists
*/
static inline int __ilog2(unsigned long x)
{
int lz;
if (sizeof(x) == 4) {
__asm__ (
" .set push \n"
" .set mips32 \n"
" clz %0, %1 \n"
" .set pop \n"
: "=r" (lz)
: "r" (x));
return 31 - lz;
}
BUG_ON(sizeof(x) != 8);
__asm__ (
" .set push \n"
" .set mips64 \n"
" dclz %0, %1 \n"
" .set pop \n"
: "=r" (lz)
: "r" (x));
return 63 - lz;
}
/*
* __ffs - find first bit in word.
* @word: The word to search
*
* Returns 0..SZLONG-1
* Undefined if no bit exists, so code should check against 0 first.
*/
static inline unsigned long __ffs(unsigned long word)
{
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
return __ilog2(word & -word);
#else
int b = 0, s;
#ifdef CONFIG_32BIT
s = 16; if (word << 16 != 0) s = 0; b += s; word >>= s;
s = 8; if (word << 24 != 0) s = 0; b += s; word >>= s;
s = 4; if (word << 28 != 0) s = 0; b += s; word >>= s;
s = 2; if (word << 30 != 0) s = 0; b += s; word >>= s;
s = 1; if (word << 31 != 0) s = 0; b += s;
return b;
#endif
#ifdef CONFIG_64BIT
s = 32; if (word << 32 != 0) s = 0; b += s; word >>= s;
s = 16; if (word << 48 != 0) s = 0; b += s; word >>= s;
s = 8; if (word << 56 != 0) s = 0; b += s; word >>= s;
s = 4; if (word << 60 != 0) s = 0; b += s; word >>= s;
s = 2; if (word << 62 != 0) s = 0; b += s; word >>= s;
s = 1; if (word << 63 != 0) s = 0; b += s;
return b;
#endif
#endif
}
/*
* ffs - find first bit set.
* @word: The word to search
*
* Returns 1..SZLONG
* Returns 0 if no bit exists
*/
static inline unsigned long ffs(unsigned long word)
{
if (!word)
return 0;
return __ffs(word) + 1;
}
/*
* ffz - find first zero in word.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long ffz(unsigned long word)
{
return __ffs (~word);
}
/*
* fls - find last bit set.
* @word: The word to search
*
* Returns 1..SZLONG
* Returns 0 if no bit exists
*/
static inline unsigned long fls(unsigned long word)
{
#ifdef CONFIG_32BIT
#ifdef CONFIG_CPU_MIPS32
__asm__ ("clz %0, %1" : "=r" (word) : "r" (word));
return 32 - word;
#else
{
int r = 32, s;
if (word == 0)
return 0;
s = 16; if ((word & 0xffff0000)) s = 0; r -= s; word <<= s;
s = 8; if ((word & 0xff000000)) s = 0; r -= s; word <<= s;
s = 4; if ((word & 0xf0000000)) s = 0; r -= s; word <<= s;
s = 2; if ((word & 0xc0000000)) s = 0; r -= s; word <<= s;
s = 1; if ((word & 0x80000000)) s = 0; r -= s;
return r;
}
#endif
#endif /* CONFIG_32BIT */
#ifdef CONFIG_64BIT
#ifdef CONFIG_CPU_MIPS64
__asm__ ("dclz %0, %1" : "=r" (word) : "r" (word));
return 64 - word;
#else
{
int r = 64, s;
if (word == 0)
return 0;
s = 32; if ((word & 0xffffffff00000000UL)) s = 0; r -= s; word <<= s;
s = 16; if ((word & 0xffff000000000000UL)) s = 0; r -= s; word <<= s;
s = 8; if ((word & 0xff00000000000000UL)) s = 0; r -= s; word <<= s;
s = 4; if ((word & 0xf000000000000000UL)) s = 0; r -= s; word <<= s;
s = 2; if ((word & 0xc000000000000000UL)) s = 0; r -= s; word <<= s;
s = 1; if ((word & 0x8000000000000000UL)) s = 0; r -= s;
return r;
}
#endif
#endif /* CONFIG_64BIT */
}
#define fls64(x) generic_fls64(x)
/*
* 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
*/
static inline unsigned long find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
const unsigned long *p = addr + (offset >> SZLONG_LOG);
unsigned long result = offset & ~SZLONG_MASK;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= SZLONG_MASK;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (_MIPS_SZLONG-offset);
if (size < _MIPS_SZLONG)
goto found_first;
if (~tmp)
goto found_middle;
size -= _MIPS_SZLONG;
result += _MIPS_SZLONG;
}
while (size & ~SZLONG_MASK) {
if (~(tmp = *(p++)))
goto found_middle;
result += _MIPS_SZLONG;
size -= _MIPS_SZLONG;
}
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);
}
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
/*
* 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)
{
const unsigned long *p = addr + (offset >> SZLONG_LOG);
unsigned long result = offset & ~SZLONG_MASK;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= SZLONG_MASK;
if (offset) {
tmp = *(p++);
tmp &= ~0UL << offset;
if (size < _MIPS_SZLONG)
goto found_first;
if (tmp)
goto found_middle;
size -= _MIPS_SZLONG;
result += _MIPS_SZLONG;
}
while (size & ~SZLONG_MASK) {
if ((tmp = *(p++)))
goto found_middle;
result += _MIPS_SZLONG;
size -= _MIPS_SZLONG;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= ~0UL >> (_MIPS_SZLONG - 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)
#ifdef __KERNEL__
/*
* 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(const unsigned long *b)
{
#ifdef CONFIG_32BIT
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;
#endif
#ifdef CONFIG_64BIT
if (unlikely(b[0]))
return __ffs(b[0]);
if (unlikely(b[1]))
return __ffs(b[1]) + 64;
return __ffs(b[2]) + 128;
#endif
}
/*
* 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 hweight64(x) generic_hweight64(x)
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
static inline int __test_and_set_le_bit(unsigned long nr, unsigned long *addr)
{
unsigned char *ADDR = (unsigned char *) addr;
int mask, retval;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = (mask & *ADDR) != 0;
*ADDR |= mask;
return retval;
}
static inline int __test_and_clear_le_bit(unsigned long nr, unsigned long *addr)
{
unsigned char *ADDR = (unsigned char *) addr;
int mask, retval;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = (mask & *ADDR) != 0;
*ADDR &= ~mask;
return retval;
}
static inline int test_le_bit(unsigned long nr, const unsigned long * addr)
{
const unsigned char *ADDR = (const unsigned char *) addr;
int mask;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
return ((mask & *ADDR) != 0);
}
static inline unsigned long find_next_zero_le_bit(unsigned long *addr,
unsigned long size, unsigned long offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> SZLONG_LOG);
unsigned long result = offset & ~SZLONG_MASK;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= SZLONG_MASK;
if (offset) {
tmp = cpu_to_lelongp(p++);
tmp |= ~0UL >> (_MIPS_SZLONG-offset); /* bug or feature ? */
if (size < _MIPS_SZLONG)
goto found_first;
if (~tmp)
goto found_middle;
size -= _MIPS_SZLONG;
result += _MIPS_SZLONG;
}
while (size & ~SZLONG_MASK) {
if (~(tmp = cpu_to_lelongp(p++)))
goto found_middle;
result += _MIPS_SZLONG;
size -= _MIPS_SZLONG;
}
if (!size)
return result;
tmp = cpu_to_lelongp(p);
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
#define find_first_zero_le_bit(addr, size) \
find_next_zero_le_bit((addr), (size), 0)
#define ext2_set_bit(nr,addr) \
__test_and_set_le_bit((nr),(unsigned long*)addr)
#define ext2_clear_bit(nr, addr) \
__test_and_clear_le_bit((nr),(unsigned long*)addr)
#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; \
})
#define ext2_test_bit(nr, addr) test_le_bit((nr),(unsigned long*)addr)
#define ext2_find_first_zero_bit(addr, size) \
find_first_zero_le_bit((unsigned long*)addr, size)
#define ext2_find_next_zero_bit(addr, size, off) \
find_next_zero_le_bit((unsigned long*)addr, size, off)
/*
* 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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