barrier.h 1.8 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /*
  3. * Copyright IBM Corp. 1999, 2009
  4. *
  5. * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
  6. */
  7. #ifndef __ASM_BARRIER_H
  8. #define __ASM_BARRIER_H
  9. /*
  10. * Force strict CPU ordering.
  11. * And yes, this is required on UP too when we're talking
  12. * to devices.
  13. */
  14. #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
  15. /* Fast-BCR without checkpoint synchronization */
  16. #define __ASM_BARRIER "bcr 14,0\n"
  17. #else
  18. #define __ASM_BARRIER "bcr 15,0\n"
  19. #endif
  20. #define mb() do { asm volatile(__ASM_BARRIER : : : "memory"); } while (0)
  21. #define rmb() barrier()
  22. #define wmb() barrier()
  23. #define dma_rmb() mb()
  24. #define dma_wmb() mb()
  25. #define __smp_mb() mb()
  26. #define __smp_rmb() rmb()
  27. #define __smp_wmb() wmb()
  28. #define __smp_store_release(p, v) \
  29. do { \
  30. compiletime_assert_atomic_type(*p); \
  31. barrier(); \
  32. WRITE_ONCE(*p, v); \
  33. } while (0)
  34. #define __smp_load_acquire(p) \
  35. ({ \
  36. typeof(*p) ___p1 = READ_ONCE(*p); \
  37. compiletime_assert_atomic_type(*p); \
  38. barrier(); \
  39. ___p1; \
  40. })
  41. #define __smp_mb__before_atomic() barrier()
  42. #define __smp_mb__after_atomic() barrier()
  43. /**
  44. * array_index_mask_nospec - generate a mask for array_idx() that is
  45. * ~0UL when the bounds check succeeds and 0 otherwise
  46. * @index: array element index
  47. * @size: number of elements in array
  48. */
  49. #define array_index_mask_nospec array_index_mask_nospec
  50. static inline unsigned long array_index_mask_nospec(unsigned long index,
  51. unsigned long size)
  52. {
  53. unsigned long mask;
  54. if (__builtin_constant_p(size) && size > 0) {
  55. asm(" clgr %2,%1\n"
  56. " slbgr %0,%0\n"
  57. :"=d" (mask) : "d" (size-1), "d" (index) :"cc");
  58. return mask;
  59. }
  60. asm(" clgr %1,%2\n"
  61. " slbgr %0,%0\n"
  62. :"=d" (mask) : "d" (size), "d" (index) :"cc");
  63. return ~mask;
  64. }
  65. #include <asm-generic/barrier.h>
  66. #endif /* __ASM_BARRIER_H */