* Copyright 1992, Linus Torvalds.
*/
-#ifndef _LINUX_BITOPS_H
-#error only <linux/bitops.h> can be included directly
-#endif
-
-#include <asm/alternative.h>
-
-#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 1)
-/* Technically wrong, but this avoids compilation errors on some gcc
- versions. */
-#define ADDR "=m" (*(volatile long *) addr)
-#else
-#define ADDR "+m" (*(volatile long *) addr)
-#endif
-
-/**
- * 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(int nr, volatile void *addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btsl %1,%0"
- :ADDR
- :"dIr" (nr) : "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.
- */
-static inline void __set_bit(int nr, volatile void *addr)
-{
- __asm__ volatile(
- "btsl %1,%0"
- :ADDR
- :"dIr" (nr) : "memory");
-}
-
-/**
- * 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(int nr, volatile void *addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btrl %1,%0"
- :ADDR
- :"dIr" (nr));
-}
-
-/*
- * clear_bit_unlock - Clears a bit in memory
- * @nr: Bit to clear
- * @addr: Address to start counting from
- *
- * clear_bit() is atomic and implies release semantics before the memory
- * operation. It can be used for an unlock.
- */
-static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
-{
- barrier();
- clear_bit(nr, addr);
-}
-
-static inline void __clear_bit(int nr, volatile void *addr)
-{
- __asm__ __volatile__(
- "btrl %1,%0"
- :ADDR
- :"dIr" (nr));
-}
-
-/*
- * __clear_bit_unlock - Clears a bit in memory
- * @nr: Bit to clear
- * @addr: Address to start counting from
- *
- * __clear_bit() is non-atomic and implies release semantics before the memory
- * operation. It can be used for an unlock if no other CPUs can concurrently
- * modify other bits in the word.
- *
- * No memory barrier is required here, because x86 cannot reorder stores past
- * older loads. Same principle as spin_unlock.
- */
-static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
-{
- barrier();
- __clear_bit(nr, addr);
-}
-
-#define smp_mb__before_clear_bit() barrier()
-#define smp_mb__after_clear_bit() barrier()
-
-/**
- * __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(int nr, volatile void *addr)
-{
- __asm__ __volatile__(
- "btcl %1,%0"
- :ADDR
- :"dIr" (nr));
-}
-
-/**
- * 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(int nr, volatile void *addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btcl %1,%0"
- :ADDR
- :"dIr" (nr));
-}
-
-/**
- * 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(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr) : "memory");
- return oldbit;
-}
-
-/**
- * test_and_set_bit_lock - Set a bit and return its old value for lock
- * @nr: Bit to set
- * @addr: Address to count from
- *
- * This is the same as test_and_set_bit on x86.
- */
-static inline int test_and_set_bit_lock(int nr, volatile void *addr)
-{
- return test_and_set_bit(nr, addr);
-}
-
-/**
- * __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(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__(
- "btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr));
- return oldbit;
-}
-
-/**
- * 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(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr) : "memory");
- return oldbit;
-}
-
-/**
- * __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(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__(
- "btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr));
- return oldbit;
-}
-
-/* WARNING: non atomic and it can be reordered! */
-static inline int __test_and_change_bit(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__ __volatile__(
- "btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr) : "memory");
- return oldbit;
-}
-
-/**
- * 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(int nr, volatile void *addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),ADDR
- :"dIr" (nr) : "memory");
- return oldbit;
-}
-
-#if 0 /* Fool kernel-doc since it doesn't do macros yet */
-/**
- * test_bit - Determine whether a bit is set
- * @nr: bit number to test
- * @addr: Address to start counting from
- */
-static int test_bit(int nr, const volatile void *addr);
-#endif
-
-static inline int constant_test_bit(int nr, const volatile void *addr)
-{
- return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
-}
-
-static inline int variable_test_bit(int nr, volatile const void *addr)
-{
- int oldbit;
-
- __asm__ __volatile__(
- "btl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit)
- :"m" (*(volatile long *)addr),"dIr" (nr));
- return oldbit;
-}
-
-#define test_bit(nr,addr) \
-(__builtin_constant_p(nr) ? \
- constant_test_bit((nr),(addr)) : \
- variable_test_bit((nr),(addr)))
-
-#undef ADDR
-
extern long find_first_zero_bit(const unsigned long *addr, unsigned long size);
-extern long find_next_zero_bit(const unsigned long *addr, long size, long offset);
extern long find_first_bit(const unsigned long *addr, unsigned long size);
-extern long find_next_bit(const unsigned long *addr, long size, long offset);
/* return index of first bet set in val or max when no bit is set */
static inline long __scanbit(unsigned long val, unsigned long max)
return val;
}
-#define find_first_bit(addr,size) \
-((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
- (__scanbit(*(unsigned long *)addr,(size))) : \
- find_first_bit(addr,size)))
-
#define find_next_bit(addr,size,off) \
((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \
find_next_bit(addr,size,off)))
-#define find_first_zero_bit(addr,size) \
-((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
- (__scanbit(~*(unsigned long *)addr,(size))) : \
- find_first_zero_bit(addr,size)))
-
#define find_next_zero_bit(addr,size,off) \
((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \
find_next_zero_bit(addr,size,off)))
-/*
- * Find string of zero bits in a bitmap. -1 when not found.
- */
-extern unsigned long
-find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len);
+#define find_first_bit(addr, size) \
+ ((__builtin_constant_p((size)) && (size) <= BITS_PER_LONG \
+ ? (__scanbit(*(unsigned long *)(addr), (size))) \
+ : find_first_bit((addr), (size))))
-static inline void set_bit_string(unsigned long *bitmap, unsigned long i,
- int len)
-{
- unsigned long end = i + len;
- while (i < end) {
- __set_bit(i, bitmap);
- i++;
- }
-}
+#define find_first_zero_bit(addr, size) \
+ ((__builtin_constant_p((size)) && (size) <= BITS_PER_LONG \
+ ? (__scanbit(~*(unsigned long *)(addr), (size))) \
+ : find_first_zero_bit((addr), (size))))
-static inline void __clear_bit_string(unsigned long *bitmap, unsigned long i,
- int len)
-{
- unsigned long end = i + len;
+static inline void set_bit_string(unsigned long *bitmap, unsigned long i,
+ int len)
+{
+ unsigned long end = i + len;
while (i < end) {
- __clear_bit(i, bitmap);
+ __set_bit(i, bitmap);
i++;
}
-}
+}
/**
* ffz - find first zero in word.
#include <asm-generic/bitops/ext2-non-atomic.h>
-#define ext2_set_bit_atomic(lock,nr,addr) \
- test_and_set_bit((nr),(unsigned long*)addr)
-#define ext2_clear_bit_atomic(lock,nr,addr) \
- test_and_clear_bit((nr),(unsigned long*)addr)
+#define ext2_set_bit_atomic(lock, nr, addr) \
+ test_and_set_bit((nr), (unsigned long *)(addr))
+#define ext2_clear_bit_atomic(lock, nr, addr) \
+ test_and_clear_bit((nr), (unsigned long *)(addr))
#include <asm-generic/bitops/minix.h>