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linux/arch/ia64/include/asm/bitops.h
Tony Luck 7f30491ccd [IA64] Move include/asm-ia64 to arch/ia64/include/asm 
After moving the the include files there were a few clean-ups:

1) Some files used #include <asm-ia64/xyz.h>, changed to <asm/xyz.h>

2) Some comments alerted maintainers to look at various header files to
make matching updates if certain code were to be changed. Updated these
comments to use the new include paths.

3) Some header files mentioned their own names in initial comments. Just
deleted these self references.

Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-08-01 10:21:21 -07:00

469 lines
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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 __raw_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;
*p &= ~m;
return oldbitset;
}
/**
* 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 the acquisition side of the memory barrier.
*/
static __inline__ int
test_and_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);
return (old & bit) != 0;
}
/**
* __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.
*/
static __inline__ int
__test_and_change_bit (int nr, void *addr)
{
__u32 old, bit = (1 << (nr & 31));
__u32 *m = (__u32 *) addr + (nr >> 5);
old = *m;
*m = old ^ bit;
return (old & bit) != 0;
}
static __inline__ int
test_bit (int nr, const volatile void *addr)
{
return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
}
/**
* ffz - find the first zero bit in a long word
* @x: The long word to find the bit in
*
* Returns the bit-number (0..63) of the first (least significant) zero bit.
* Undefined if no zero exists, so code should check against ~0UL first...
*/
static inline unsigned long
ffz (unsigned long x)
{
unsigned long result;
result = ia64_popcnt(x & (~x - 1));
return result;
}
/**
* __ffs - find first bit in word.
* @x: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static __inline__ unsigned long
__ffs (unsigned long x)
{
unsigned long result;
result = ia64_popcnt((x-1) & ~x);
return result;
}
#ifdef __KERNEL__
/*
* Return bit number of last (most-significant) bit set. Undefined
* for x==0. Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
*/
static inline unsigned long
ia64_fls (unsigned long x)
{
long double d = x;
long exp;
exp = ia64_getf_exp(d);
return exp - 0xffff;
}
/*
* Find the last (most significant) bit set. Returns 0 for x==0 and
* bits are numbered from 1..32 (e.g., fls(9) == 4).
*/
static inline int
fls (int t)
{
unsigned long x = t & 0xffffffffu;
if (!x)
return 0;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
return ia64_popcnt(x);
}
/*
* Find the last (most significant) bit set. Undefined for x==0.
* Bits are numbered from 0..63 (e.g., __fls(9) == 3).
*/
static inline unsigned long
__fls (unsigned long x)
{
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
x |= x >> 32;
return ia64_popcnt(x) - 1;
}
#include <asm-generic/bitops/fls64.h>
/*
* ffs: find first bit set. This is defined the same way as the libc and
* compiler builtin ffs routines, therefore differs in spirit from the above
* ffz (man ffs): it operates on "int" values only and the result value is the
* bit number + 1. ffs(0) is defined to return zero.
*/
#define ffs(x) __builtin_ffs(x)
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
*/
static __inline__ unsigned long
hweight64 (unsigned long x)
{
unsigned long result;
result = ia64_popcnt(x);
return result;
}
#define hweight32(x) (unsigned int) hweight64((x) & 0xfffffffful)
#define hweight16(x) (unsigned int) hweight64((x) & 0xfffful)
#define hweight8(x) (unsigned int) hweight64((x) & 0xfful)
#endif /* __KERNEL__ */
#include <asm-generic/bitops/find.h>
#ifdef __KERNEL__
#include <asm-generic/bitops/ext2-non-atomic.h>
#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
#include <asm-generic/bitops/minix.h>
#include <asm-generic/bitops/sched.h>
#endif /* __KERNEL__ */
#endif /* _ASM_IA64_BITOPS_H */
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