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#ifndef _ASM_IA64_BITOPS_H
#define _ASM_IA64_BITOPS_H
/*
* Copyright (C) 1998-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
* O(1) scheduler patch
*/
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/intrinsics.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.
*
* The address must be (at least) "long" aligned.
* Note that there are driver (e.g., eepro100) which use these operations to
* operate on hw-defined data-structures, so we can't easily change these
* operations to force a bigger alignment.
*
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*/
static __inline__ void
set_bit (int nr, volatile void *addr)
{
__u32 bit, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
bit = 1 << (nr & 31);
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old | bit;
} while (cmpxchg_acq(m, old, new) != old);
}
/**
* __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)
{
*((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
}
/*
* clear_bit() has "acquire" semantics.
*/
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() do { /* skip */; } while (0)
/**
* 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)
{
__u32 mask, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
mask = ~(1 << (nr & 31));
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old & mask;
} while (cmpxchg_acq(m, old, new) != old);
}
/**
* clear_bit_unlock - Clears a bit in memory with release
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit_unlock() is atomic and may not be reordered. It does
* contain a memory barrier suitable for unlock type operations.
*/
static __inline__ void
clear_bit_unlock (int nr, volatile void *addr)
{
__u32 mask, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
mask = ~(1 << (nr & 31));
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old & mask;
} while (cmpxchg_rel(m, old, new) != old);
}
/**
* __clear_bit_unlock - Non-atomically clears a bit in memory with release
* @nr: Bit to clear
* @addr: Address to start counting from
*
* Similarly to clear_bit_unlock, the implementation uses a store
* with release semantics. See also arch_spin_unlock().
*/
static __inline__ void
__clear_bit_unlock(int nr, void *addr)
{
__u32 * const m = (__u32 *) addr + (nr >> 5);
__u32 const new = *m & ~(1 << (nr & 31));
ia64_st4_rel_nta(m, new);
}
/**
* __clear_bit - Clears a bit in memory (non-atomic version)
* @nr: the bit to clear
* @addr: the 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 (int nr, volatile void *addr)
{
*((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
}
/**
* change_bit - Toggle a bit in memory
* @nr: Bit to toggle
* @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)
{
__u32 bit, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
bit = (1 << (nr & 31));
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old ^ bit;
} while (cmpxchg_acq(m, old, new) != old);
}
/**
* __change_bit - Toggle a bit in memory
* @nr: the bit to toggle
* @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)
{
*((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
}
/**
* 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 the acquisition side of the memory barrier.
*/
static __inline__ int
test_and_set_bit (int nr, volatile void *addr)
{
__u32 bit, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
bit = 1 << (nr & 31);
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old | bit;
} while (cmpxchg_acq(m, old, new) != old);
return (old & bit) != 0;
}
/**
* 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 ia64
*/
#define test_and_set_bit_lock test_and_set_bit
/**
* __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)
{
__u32 *p = (__u32 *) addr + (nr >> 5);
__u32 m = 1 << (nr & 31);
int oldbitset = (*p & m) != 0;
*p |= m;
return oldbitset;
}
/**
* 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 the acquisition side of the memory barrier.
*/
static __inline__ int
test_and_clear_bit (int nr, volatile void *addr)
{
__u32 mask, old, new;
volatile __u32 *m;
CMPXCHG_BUGCHECK_DECL
m = (volatile __u32 *) addr + (nr >> 5);
mask = ~(1 << (nr & 31));
do {
CMPXCHG_BUGCHECK(m);
old = *m;
new = old & mask;
} while (cmpxchg_acq(m, old, new) != old);
return (old & ~mask) != 0;
}
/**
* __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)
{
__u32 *p = (__u32 *) addr + (nr >> 5);
__u32 m = 1 << (nr & 31);
int oldbitset = (*p & m) != 0;
*p &= ~m;
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