futex.h 3.1 KB

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  1. #ifndef _ASM_FUTEX_H
  2. #define _ASM_FUTEX_H
  3. #include <linux/futex.h>
  4. #include <linux/uaccess.h>
  5. #include <asm/errno.h>
  6. #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
  7. do { \
  8. register unsigned long r8 __asm ("r8") = 0; \
  9. __asm__ __volatile__( \
  10. " mf;; \n" \
  11. "[1:] " insn ";; \n" \
  12. " .xdata4 \"__ex_table\", 1b-., 2f-. \n" \
  13. "[2:]" \
  14. : "+r" (r8), "=r" (oldval) \
  15. : "r" (uaddr), "r" (oparg) \
  16. : "memory"); \
  17. ret = r8; \
  18. } while (0)
  19. #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
  20. do { \
  21. register unsigned long r8 __asm ("r8") = 0; \
  22. int val, newval; \
  23. do { \
  24. __asm__ __volatile__( \
  25. " mf;; \n" \
  26. "[1:] ld4 %3=[%4];; \n" \
  27. " mov %2=%3 \n" \
  28. insn ";; \n" \
  29. " mov ar.ccv=%2;; \n" \
  30. "[2:] cmpxchg4.acq %1=[%4],%3,ar.ccv;; \n" \
  31. " .xdata4 \"__ex_table\", 1b-., 3f-.\n" \
  32. " .xdata4 \"__ex_table\", 2b-., 3f-.\n" \
  33. "[3:]" \
  34. : "+r" (r8), "=r" (val), "=&r" (oldval), \
  35. "=&r" (newval) \
  36. : "r" (uaddr), "r" (oparg) \
  37. : "memory"); \
  38. if (unlikely (r8)) \
  39. break; \
  40. } while (unlikely (val != oldval)); \
  41. ret = r8; \
  42. } while (0)
  43. static inline int
  44. futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
  45. {
  46. int op = (encoded_op >> 28) & 7;
  47. int cmp = (encoded_op >> 24) & 15;
  48. int oparg = (encoded_op << 8) >> 20;
  49. int cmparg = (encoded_op << 20) >> 20;
  50. int oldval = 0, ret;
  51. if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
  52. oparg = 1 << oparg;
  53. if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
  54. return -EFAULT;
  55. pagefault_disable();
  56. switch (op) {
  57. case FUTEX_OP_SET:
  58. __futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr,
  59. oparg);
  60. break;
  61. case FUTEX_OP_ADD:
  62. __futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg);
  63. break;
  64. case FUTEX_OP_OR:
  65. __futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg);
  66. break;
  67. case FUTEX_OP_ANDN:
  68. __futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr,
  69. ~oparg);
  70. break;
  71. case FUTEX_OP_XOR:
  72. __futex_atomic_op2("xor %3=%3,%5", ret, oldval, uaddr, oparg);
  73. break;
  74. default:
  75. ret = -ENOSYS;
  76. }
  77. pagefault_enable();
  78. if (!ret) {
  79. switch (cmp) {
  80. case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
  81. case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
  82. case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
  83. case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
  84. case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
  85. case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
  86. default: ret = -ENOSYS;
  87. }
  88. }
  89. return ret;
  90. }
  91. static inline int
  92. futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  93. u32 oldval, u32 newval)
  94. {
  95. if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
  96. return -EFAULT;
  97. {
  98. register unsigned long r8 __asm ("r8") = 0;
  99. unsigned long prev;
  100. __asm__ __volatile__(
  101. " mf;; \n"
  102. " mov ar.ccv=%4;; \n"
  103. "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n"
  104. " .xdata4 \"__ex_table\", 1b-., 2f-. \n"
  105. "[2:]"
  106. : "+r" (r8), "=&r" (prev)
  107. : "r" (uaddr), "r" (newval),
  108. "rO" ((long) (unsigned) oldval)
  109. : "memory");
  110. *uval = prev;
  111. return r8;
  112. }
  113. }
  114. #endif /* _ASM_FUTEX_H */