arch/s390/include/asm/cmpxchg.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright IBM Corp. 1999, 2011
   4  *
   5  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
   6  */
   7
   8 #ifndef __ASM_CMPXCHG_H
   9 #define __ASM_CMPXCHG_H
  10
  11 #include <linux/mmdebug.h>
  12 #include <linux/types.h>
  13 #include <linux/bug.h>
  14
  15 #define cmpxchg(ptr, o, n)                                              \
  16 ({                                                                      \
  17         __typeof__(*(ptr)) __o = (o);                                   \
  18         __typeof__(*(ptr)) __n = (n);                                   \
  19         (__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\
  20 })
  21
  22 #define cmpxchg64       cmpxchg
  23 #define cmpxchg_local   cmpxchg
  24 #define cmpxchg64_local cmpxchg
  25
  26 #define xchg(ptr, x)                                                    \
  27 ({                                                                      \
  28         __typeof__(ptr) __ptr = (ptr);                                  \
  29         __typeof__(*(ptr)) __old;                                       \
  30         do {                                                            \
  31                 __old = *__ptr;                                         \
  32         } while (!__sync_bool_compare_and_swap(__ptr, __old, x));       \
  33         __old;                                                          \
  34 })
  35
  36 #define __cmpxchg_double(p1, p2, o1, o2, n1, n2)                        \
  37 ({                                                                      \
  38         register __typeof__(*(p1)) __old1 asm("2") = (o1);              \
  39         register __typeof__(*(p2)) __old2 asm("3") = (o2);              \
  40         register __typeof__(*(p1)) __new1 asm("4") = (n1);              \
  41         register __typeof__(*(p2)) __new2 asm("5") = (n2);              \
  42         int cc;                                                         \
  43         asm volatile(                                                   \
  44                 "       cdsg    %[old],%[new],%[ptr]\n"                 \
  45                 "       ipm     %[cc]\n"                                \
  46                 "       srl     %[cc],28"                               \
  47                 : [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2)    \
  48                 : [new] "d" (__new1), "d" (__new2),                     \
  49                   [ptr] "Q" (*(p1)), "Q" (*(p2))                        \
  50                 : "memory", "cc");                                      \
  51         !cc;                                                            \
  52 })
  53
  54 #define cmpxchg_double(p1, p2, o1, o2, n1, n2)                          \
  55 ({                                                                      \
  56         __typeof__(p1) __p1 = (p1);                                     \
  57         __typeof__(p2) __p2 = (p2);                                     \
  58         BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long));                    \
  59         BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));                    \
  60         VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
  61         __cmpxchg_double(__p1, __p2, o1, o2, n1, n2);                   \
  62 })
  63
  64 #define system_has_cmpxchg_double()     1
  65
  66 #endif /* __ASM_CMPXCHG_H */