* Copyright 1992, Linus Torvalds.
*/
-#ifndef _LINUX_BITOPS_H
-#error only <linux/bitops.h> can be included directly
-#endif
-
-#include <linux/compiler.h>
-#include <asm/alternative.h>
-
-/*
- * These have to be done with inline assembly: that way the bit-setting
- * is guaranteed to be atomic. All bit operations return 0 if the bit
- * was cleared before the operation and != 0 if it was not.
- *
- * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
- */
-
-#define ADDR (*(volatile long *) addr)
-
-/**
- * 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: there are no guarantees that this function will not be reordered
- * on non x86 architectures, so if you are writing portable code,
- * make sure not to rely on its reordering 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 unsigned long * addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btsl %1,%0"
- :"+m" (ADDR)
- :"Ir" (nr));
-}
-
-/**
- * __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 unsigned long * addr)
-{
- __asm__(
- "btsl %1,%0"
- :"+m" (ADDR)
- :"Ir" (nr));
-}
-
-/**
- * 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 unsigned long * addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btrl %1,%0"
- :"+m" (ADDR)
- :"Ir" (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 unsigned long * addr)
-{
- __asm__ __volatile__(
- "btrl %1,%0"
- :"+m" (ADDR)
- :"Ir" (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 unsigned long * addr)
-{
- __asm__ __volatile__(
- "btcl %1,%0"
- :"+m" (ADDR)
- :"Ir" (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. It may be
- * reordered on other architectures than x86.
- * 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 unsigned long * addr)
-{
- __asm__ __volatile__( LOCK_PREFIX
- "btcl %1,%0"
- :"+m" (ADDR)
- :"Ir" (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 may be reordered on other architectures than x86.
- * It also implies a memory barrier.
- */
-static inline int test_and_set_bit(int nr, volatile unsigned long * addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (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 unsigned long *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 unsigned long * addr)
-{
- int oldbit;
-
- __asm__(
- "btsl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (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 can be reorderdered on other architectures other than x86.
- * It also implies a memory barrier.
- */
-static inline int test_and_clear_bit(int nr, volatile unsigned long * addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (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 unsigned long *addr)
-{
- int oldbit;
-
- __asm__(
- "btrl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (nr));
- return oldbit;
-}
-
-/* WARNING: non atomic and it can be reordered! */
-static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
-{
- int oldbit;
-
- __asm__ __volatile__(
- "btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (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 unsigned long* addr)
-{
- int oldbit;
-
- __asm__ __volatile__( LOCK_PREFIX
- "btcl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit),"+m" (ADDR)
- :"Ir" (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 __always_inline int constant_test_bit(int nr, const volatile unsigned long *addr)
-{
- return ((1UL << (nr & 31)) & (addr[nr >> 5])) != 0;
-}
-
-static inline int variable_test_bit(int nr, const volatile unsigned long * addr)
-{
- int oldbit;
-
- __asm__ __volatile__(
- "btl %2,%1\n\tsbbl %0,%0"
- :"=r" (oldbit)
- :"m" (ADDR),"Ir" (nr));
- return oldbit;
-}
-
-#define test_bit(nr,addr) \
-(__builtin_constant_p(nr) ? \
- constant_test_bit((nr),(addr)) : \
- variable_test_bit((nr),(addr)))
-
-#undef ADDR
-
/**
* 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
+ * Returns the bit number of the first zero bit, not the number of the byte
* containing a bit.
*/
static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
/**
* 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
+ * @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_zero_bit(const unsigned long *addr, int size, int offset);
* @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
+ * Returns the bit number of the first set bit, not the number of the byte
* containing a bit.
*/
static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
/**
* find_next_bit - find the first set bit in a memory region
* @addr: The address to base the search on
- * @offset: The bitnumber to start searching at
+ * @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_bit(const unsigned long *addr, int size, int offset);
#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>
projects / linux-flexiantxendom0-3.2.10.git / blobdiff