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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_ATOMIC64_64_H
#define _ASM_X86_ATOMIC64_64_H
#include <linux/types.h>
#include <asm/alternative.h>
#include <asm/cmpxchg.h>
/* The 64-bit atomic type */
#define ATOMIC64_INIT(i) { (i) }
/**
* atomic64_read - read atomic64 variable
* @v: pointer of type atomic64_t
*
* Atomically reads the value of @v.
* Doesn't imply a read memory barrier.
*/
static inline long atomic64_read(const atomic64_t *v)
{
return READ_ONCE((v)->counter);
}
/**
* atomic64_set - set atomic64 variable
* @v: pointer to type atomic64_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*/
static inline void atomic64_set(atomic64_t *v, long i)
{
WRITE_ONCE(v->counter, i);
}
/**
* atomic64_add - add integer to atomic64 variable
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v.
*/
static __always_inline void atomic64_add(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "addq %1,%0"
: "=m" (v->counter)
: "er" (i), "m" (v->counter));
}
/**
* atomic64_sub - subtract the atomic64 variable
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v.
*/
static inline void atomic64_sub(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "subq %1,%0"
: "=m" (v->counter)
: "er" (i), "m" (v->counter));
}
/**
* atomic64_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
static inline bool atomic64_sub_and_test(long i, atomic64_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "subq", v->counter, "er", i, "%0", e);
}
/**
* atomic64_inc - increment atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1.
*/
static __always_inline void atomic64_inc(atomic64_t *v)
{
asm volatile(LOCK_PREFIX "incq %0"
: "=m" (v->counter)
: "m" (v->counter));
}
/**
* atomic64_dec - decrement atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically decrements @v by 1.
*/
static __always_inline void atomic64_dec(atomic64_t *v)
{
asm volatile(LOCK_PREFIX "decq %0"
: "=m" (v->counter)
: "m" (v->counter));
}
/**
* atomic64_dec_and_test - decrement and test
* @v: pointer to type atomic64_t
*
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all other
* cases.
*/
static inline bool atomic64_dec_and_test(atomic64_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "decq", v->counter, "%0", e);
}
/**
* atomic64_inc_and_test - increment and test
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
static inline bool atomic64_inc_and_test(atomic64_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "incq", v->counter, "%0", e);
}
/**
* atomic64_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
static inline bool atomic64_add_negative(long i, atomic64_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "addq", v->counter, "er", i, "%0", s);
}
/**
* atomic64_add_return - add and return
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns @i + @v
*/
static __always_inline long atomic64_add_return(long i, atomic64_t *v)
{
return i + xadd(&v->counter, i);
}
static inline long atomic64_sub_return(long i, atomic64_t *v)
{
return atomic64_add_return(-i, v);
}
static inline long atomic64_fetch_add(long i, atomic64_t *v)
{
return xadd(&v->counter, i);
}
static inline long atomic64_fetch_sub(long i, atomic64_t *v)
{
return xadd(&v->counter, -i);
}
#define atomic64_inc_return(v) (atomic64_add_return(1, (v)))
#define atomic64_dec_return(v) (atomic64_sub_return(1, (v)))
static inline long atomic64_cmpxchg(atomic64_t *v, long old, long new)
{
return cmpxchg(&v->counter, old, new);
}
#define atomic64_try_cmpxchg atomic64_try_cmpxchg
static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, s64 *old, long new)
{
return try_cmpxchg(&v->counter, old, new);
}
static inline long atomic64_xchg(atomic64_t *v, long new)
{
return xchg(&v->counter, new);
}
/**
* atomic64_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns the old value of @v.
*/
static inline bool atomic64_add_unless(atomic64_t *v, long a, long u)
{
s64 c = atomic64_read(v);
do {
if (unlikely(c == u))
return false;
} while (!atomic64_try_cmpxchg(v, &c, c + a));
return true;
}
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
/*
* atomic64_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic_t
*
* The function returns the old value of *v minus 1, even if
* the atomic variable, v, was not decremented.
*/
static inline long atomic64_dec_if_positive(atomic64_t *v)
{
s64 dec, c = atomic64_read(v);
do {
dec = c - 1;
if (unlikely(dec < 0))
break;
} while (!atomic64_try_cmpxchg(v, &c, dec));
return dec;
}
static inline void atomic64_and(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "andq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
static inline long atomic64_fetch_and(long i, atomic64_t *v)
{
s64 val = atomic64_read(v);
do {
} while (!atomic64_try_cmpxchg(v, &val, val & i));
return val;
}
static inline void atomic64_or(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "orq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
static inline long atomic64_fetch_or(long i, atomic64_t *v)
{
s64 val = atomic64_read(v);
do {
} while (!atomic64_try_cmpxchg(v, &val, val | i));
return val;
}
static inline void atomic64_xor(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "xorq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
static inline long atomic64_fetch_xor(long i, atomic64_t *v)
{
s64 val = atomic64_read(v);
do {
} while (!atomic64_try_cmpxchg(v, &val, val ^ i));
return val;
}
#endif /* _ASM_X86_ATOMIC64_64_H */
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