/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_LOCAL_H
#define _ASM_X86_LOCAL_H

#include <linux/percpu.h>

#include <linux/atomic.h>
#include <linux/local.h>
#include <asm/asm.h>

typedef struct {
    atomic_long_t a;
} local_t;

typedef struct {
    atomic_long_unchecked_t a;
} local_unchecked_t;

#define LOCAL_INIT(i)    { ATOMIC_LONG_INIT(i) }

static inline long local_read(const local_t *l)
{
    return atomic_long_read(&l->a);
}

static inline long local_read_unchecked(const local_unchecked_t *l)
{
    return atomic_long_read(&l->a);
}

static inline void local_set(local_t *l, long i)
{
    atomic_long_set(&l->a, (i));
}

static inline void local_set_unchecked(local_unchecked_t *l, long i)
{
    atomic_long_set(&l->a, (i));
}

static inline void local_inc(local_t *l)
{
    asm volatile(_ASM_INC "%0\n\t"
             PAX_REFCOUNT_OVERFLOW(BITS_PER_LONG)
             : [counter] "+m" (l->a.counter)
             : : "cc", "cx");
}

static inline void local_inc_unchecked(local_unchecked_t *l)
{
    asm volatile(_ASM_INC "%0\n"
             : "+m" (l->a.counter));
}

static inline void local_dec(local_t *l)
{
    asm volatile(_ASM_DEC "%0\n\t"
             PAX_REFCOUNT_UNDERFLOW(BITS_PER_LONG)
             : [counter] "+m" (l->a.counter)
             : : "cc", "cx");
}

static inline void local_dec_unchecked(local_unchecked_t *l)
{
    asm volatile(_ASM_DEC "%0\n"
             : "+m" (l->a.counter));
}

static inline void local_add(long i, local_t *l)
{
    asm volatile(_ASM_ADD "%1,%0\n\t"
             PAX_REFCOUNT_OVERFLOW(BITS_PER_LONG)
             : [counter] "+m" (l->a.counter)
             : "ir" (i)
             : "cc", "cx");
}

static inline void local_add_unchecked(long i, local_unchecked_t *l)
{
    asm volatile(_ASM_ADD "%1,%0\n"
             : "+m" (l->a.counter)
             : "ir" (i));
}

static inline void local_sub(long i, local_t *l)
{
    asm volatile(_ASM_SUB "%1,%0\n\t"
             PAX_REFCOUNT_UNDERFLOW(BITS_PER_LONG)
             : [counter] "+m" (l->a.counter)
             : "ir" (i)
             : "cc", "cx");
}

static inline void local_sub_unchecked(long i, local_unchecked_t *l)
{
    asm volatile(_ASM_SUB "%1,%0\n"
             : "+m" (l->a.counter)
             : "ir" (i));
}

/**
 * local_sub_and_test - subtract value from variable and test result
 * @i: integer value to subtract
 * @l: pointer to type local_t
 *
 * Atomically subtracts @i from @l and returns
 * true if the result is zero, or false for all
 * other cases.
 */
static inline bool local_sub_and_test(long i, local_t *l)
{
    return GEN_BINARY_RMWcc(_ASM_SUB, l->a.counter, underflow, BITS_PER_LONG, e, "er", i);
}

/**
 * local_dec_and_test - decrement and test
 * @l: pointer to type local_t
 *
 * Atomically decrements @l by 1 and
 * returns true if the result is 0, or false for all other
 * cases.
 */
static inline bool local_dec_and_test(local_t *l)
{
    return GEN_UNARY_RMWcc(_ASM_DEC, l->a.counter, underflow, BITS_PER_LONG, e);
}

/**
 * local_inc_and_test - increment and test
 * @l: pointer to type local_t
 *
 * Atomically increments @l by 1
 * and returns true if the result is zero, or false for all
 * other cases.
 */
static inline bool local_inc_and_test(local_t *l)
{
    return GEN_UNARY_RMWcc(_ASM_INC, l->a.counter, overflow, BITS_PER_LONG, e);
}

/**
 * local_add_negative - add and test if negative
 * @i: integer value to add
 * @l: pointer to type local_t
 *
 * Atomically adds @i to @l and returns true
 * if the result is negative, or false when
 * result is greater than or equal to zero.
 */
static inline bool local_add_negative(long i, local_t *l)
{
    return GEN_BINARY_RMWcc(_ASM_ADD, l->a.counter, overflow, BITS_PER_LONG, s, "er", i);
}

/**
 * local_add_return - add and return
 * @i: integer value to add
 * @l: pointer to type local_t
 *
 * Atomically adds @i to @l and returns @i + @l
 */
static inline long local_add_return(long i, local_t *l)
{
    long __i = i;
    asm volatile(_ASM_XADD "%0, %1\n\t"
             PAX_REFCOUNT_OVERFLOW(BITS_PER_LONG)
             : "+r" (i), [counter] "+m" (l->a.counter)
             : : "memory", "cc", "cx");
    return i + __i;
}

/**
 * local_add_return_unchecked - add and return
 * @i: integer value to add
 * @l: pointer to type local_unchecked_t
 *
 * Atomically adds @i to @l and returns @i + @l
 */
static inline long local_add_return_unchecked(long i, local_unchecked_t *l)
{
    long __i = i;
    asm volatile(_ASM_XADD "%0, %1;"
             : "+r" (i), "+m" (l->a.counter)
             : : "memory");
    return i + __i;
}

static inline long local_sub_return(long i, local_t *l)
{
    return local_add_return(-i, l);
}

#define local_inc_return(l)  (local_add_return(1, l))
#define local_dec_return(l)  (local_sub_return(1, l))

static inline long local_cmpxchg(local_t *l, long old, long new)
{
    return cmpxchg_local(&l->a.counter, old, new);
}

static inline long local_cmpxchg_unchecked(local_unchecked_t *l, long old, long new)
{
    return cmpxchg_local(&l->a.counter, old, new);
}

static inline bool local_try_cmpxchg(local_t *l, long *old, long new)
{
    return try_cmpxchg_local(&l->a.counter,
                 (typeof(l->a.counter) *) old, new);
}

static inline bool local_try_cmpxchg_unchecked(local_unchecked_t *l, long *old, long new)
{
    return try_cmpxchg_local(&l->a.counter,
                 (typeof(l->a.counter) *) old, new);
}

/* Always has a lock prefix */
#define local_xchg(l, n) (xchg(&((l)->a.counter), (n)))

/**
 * local_add_unless - add unless the number is a given value
 * @l: pointer of type local_t
 * @a: the amount to add to l...
 * @u: ...unless l is equal to u.
 *
 * Atomically adds @a to @l, so long as it was not @u.
 * Returns non-zero if @l was not @u, and zero otherwise.
 */
#define local_add_unless(l, a, u)                \
({                                \
    long c, old;                        \
    c = local_read((l));                    \
    for (;;) {                        \
        if (unlikely(c == (u)))                \
            break;                    \
        old = local_cmpxchg((l), c, c + (a));        \
        if (likely(old == c))                \
            break;                    \
        c = old;                    \
    }                            \
    c != (u);                        \
})
#define local_inc_not_zero(l) local_add_unless((l), 1, 0)

/* On x86_32, these are no better than the atomic variants.
 * On x86-64 these are better than the atomic variants on SMP kernels
 * because they dont use a lock prefix.
 */
#define __local_inc(l)        local_inc(l)
#define __local_dec(l)        local_dec(l)
#define __local_add(i, l)    local_add((i), (l))
#define __local_sub(i, l)    local_sub((i), (l))

#include <linux/local-defs.h>

#endif /* _ASM_X86_LOCAL_H */