arch/s390/include/asm/rwonce.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef __ASM_S390_RWONCE_H
   4 #define __ASM_S390_RWONCE_H
   5
   6 #include <linux/compiler_types.h>
   7
   8 /*
   9  * Use READ_ONCE_ALIGNED_128() for 128-bit block concurrent (atomic) read
  10  * accesses. Note that x must be 128-bit aligned, otherwise a specification
  11  * exception is generated.
  12  */
  13 #define READ_ONCE_ALIGNED_128(x)                        \
  14 ({                                                      \
  15         union {                                         \
  16                 typeof(x) __x;                          \
  17                 __uint128_t val;                        \
  18         } __u;                                          \
  19                                                         \
  20         BUILD_BUG_ON(sizeof(x) != 16);                  \
  21         asm volatile(                                   \
  22                 "       lpq     %[val],%[_x]\n"         \
  23                 : [val] "=d" (__u.val)                  \
  24                 : [_x] "QS" (x)                         \
  25                 : "memory");                            \
  26         __u.__x;                                        \
  27 })
  28
  29 #include <asm-generic/rwonce.h>
  30
  31 #endif  /* __ASM_S390_RWONCE_H */