arch/s390/include/asm/cmpxchg.h

   1 /*
   2  * Copyright IBM Corp. 1999, 2011
   3  *
   4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
   5  */
   6
   7 #ifndef __ASM_CMPXCHG_H
   8 #define __ASM_CMPXCHG_H
   9
  10 #include <linux/mmdebug.h>
  11 #include <linux/types.h>
  12 #include <linux/bug.h>
  13
  14 #define cmpxchg(ptr, o, n)                                              \
  15 ({                                                                      \
  16         __typeof__(*(ptr)) __o = (o);                                   \
  17         __typeof__(*(ptr)) __n = (n);                                   \
  18         (__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\
  19 })
  20
  21 #define cmpxchg64       cmpxchg
  22 #define cmpxchg_local   cmpxchg
  23 #define cmpxchg64_local cmpxchg
  24
  25 #define xchg(ptr, x)                                                    \
  26 ({                                                                      \
  27         __typeof__(ptr) __ptr = (ptr);                                  \
  28         __typeof__(*(ptr)) __old;                                       \
  29         do {                                                            \
  30                 __old = *__ptr;                                         \
  31         } while (!__sync_bool_compare_and_swap(__ptr, __old, x));       \
  32         __old;                                                          \
  33 })
  34
  35 #define __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, insn)               \
  36 ({                                                                      \
  37         register __typeof__(*(p1)) __old1 asm("2") = (o1);              \
  38         register __typeof__(*(p2)) __old2 asm("3") = (o2);              \
  39         register __typeof__(*(p1)) __new1 asm("4") = (n1);              \
  40         register __typeof__(*(p2)) __new2 asm("5") = (n2);              \
  41         int cc;                                                         \
  42         asm volatile(                                                   \
  43                         insn   " %[old],%[new],%[ptr]\n"                \
  44                 "       ipm     %[cc]\n"                                \
  45                 "       srl     %[cc],28"                               \
  46                 : [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2)    \
  47                 : [new] "d" (__new1), "d" (__new2),                     \
  48                   [ptr] "Q" (*(p1)), "Q" (*(p2))                        \
  49                 : "memory", "cc");                                      \
  50         !cc;                                                            \
  51 })
  52
  53 #define __cmpxchg_double_4(p1, p2, o1, o2, n1, n2) \
  54         __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cds")
  55
  56 #define __cmpxchg_double_8(p1, p2, o1, o2, n1, n2) \
  57         __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cdsg")
  58
  59 extern void __cmpxchg_double_called_with_bad_pointer(void);
  60
  61 #define __cmpxchg_double(p1, p2, o1, o2, n1, n2)                        \
  62 ({                                                                      \
  63         int __ret;                                                      \
  64         switch (sizeof(*(p1))) {                                        \
  65         case 4:                                                         \
  66                 __ret = __cmpxchg_double_4(p1, p2, o1, o2, n1, n2);     \
  67                 break;                                                  \
  68         case 8:                                                         \
  69                 __ret = __cmpxchg_double_8(p1, p2, o1, o2, n1, n2);     \
  70                 break;                                                  \
  71         default:                                                        \
  72                 __cmpxchg_double_called_with_bad_pointer();             \
  73         }                                                               \
  74         __ret;                                                          \
  75 })
  76
  77 #define cmpxchg_double(p1, p2, o1, o2, n1, n2)                          \
  78 ({                                                                      \
  79         __typeof__(p1) __p1 = (p1);                                     \
  80         __typeof__(p2) __p2 = (p2);                                     \
  81         BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long));                    \
  82         BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));                    \
  83         VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
  84         __cmpxchg_double_8(__p1, __p2, o1, o2, n1, n2);                 \
  85 })
  86
  87 #define system_has_cmpxchg_double()     1
  88
  89 #endif /* __ASM_CMPXCHG_H */