include/asm-generic/atomic64.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Generic implementation of 64-bit atomics using spinlocks,
   4  * useful on processors that don't have 64-bit atomic instructions.
   5  *
   6  * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
   7  */
   8 #ifndef _ASM_GENERIC_ATOMIC64_H
   9 #define _ASM_GENERIC_ATOMIC64_H
  10 #include <linux/types.h>
  11
  12 typedef struct {
  13         s64 counter;
  14 } atomic64_t;
  15
  16 #define ATOMIC64_INIT(i)        { (i) }
  17
  18 extern s64 atomic64_read(const atomic64_t *v);
  19 extern void atomic64_set(atomic64_t *v, s64 i);
  20
  21 #define atomic64_set_release(v, i)      atomic64_set((v), (i))
  22
  23 #define ATOMIC64_OP(op)                                                 \
  24 extern void      atomic64_##op(s64 a, atomic64_t *v);
  25
  26 #define ATOMIC64_OP_RETURN(op)                                          \
  27 extern s64 atomic64_##op##_return(s64 a, atomic64_t *v);
  28
  29 #define ATOMIC64_FETCH_OP(op)                                           \
  30 extern s64 atomic64_fetch_##op(s64 a, atomic64_t *v);
  31
  32 #define ATOMIC64_OPS(op)        ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) ATOMIC64_FETCH_OP(op)
  33
  34 ATOMIC64_OPS(add)
  35 ATOMIC64_OPS(sub)
  36
  37 #undef ATOMIC64_OPS
  38 #define ATOMIC64_OPS(op)        ATOMIC64_OP(op) ATOMIC64_FETCH_OP(op)
  39
  40 ATOMIC64_OPS(and)
  41 ATOMIC64_OPS(or)
  42 ATOMIC64_OPS(xor)
  43
  44 #undef ATOMIC64_OPS
  45 #undef ATOMIC64_FETCH_OP
  46 #undef ATOMIC64_OP_RETURN
  47 #undef ATOMIC64_OP
  48
  49 extern s64 atomic64_dec_if_positive(atomic64_t *v);
  50 #define atomic64_dec_if_positive atomic64_dec_if_positive
  51 extern s64 atomic64_cmpxchg(atomic64_t *v, s64 o, s64 n);
  52 extern s64 atomic64_xchg(atomic64_t *v, s64 new);
  53 extern s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u);
  54 #define atomic64_fetch_add_unless atomic64_fetch_add_unless
  55
  56 #endif  /*  _ASM_GENERIC_ATOMIC64_H  */