futex.h 2.1 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef _ASM_MICROBLAZE_FUTEX_H
  3. #define _ASM_MICROBLAZE_FUTEX_H
  4. #ifdef __KERNEL__
  5. #include <linux/futex.h>
  6. #include <linux/uaccess.h>
  7. #include <asm/errno.h>
  8. #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
  9. ({ \
  10. __asm__ __volatile__ ( \
  11. "1: lwx %0, %2, r0; " \
  12. insn \
  13. "2: swx %1, %2, r0; \
  14. addic %1, r0, 0; \
  15. bnei %1, 1b; \
  16. 3: \
  17. .section .fixup,\"ax\"; \
  18. 4: brid 3b; \
  19. addik %1, r0, %3; \
  20. .previous; \
  21. .section __ex_table,\"a\"; \
  22. .word 1b,4b,2b,4b; \
  23. .previous;" \
  24. : "=&r" (oldval), "=&r" (ret) \
  25. : "r" (uaddr), "i" (-EFAULT), "r" (oparg) \
  26. ); \
  27. })
  28. static inline int
  29. arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
  30. {
  31. int oldval = 0, ret;
  32. if (!access_ok(uaddr, sizeof(u32)))
  33. return -EFAULT;
  34. switch (op) {
  35. case FUTEX_OP_SET:
  36. __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
  37. break;
  38. case FUTEX_OP_ADD:
  39. __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
  40. break;
  41. case FUTEX_OP_OR:
  42. __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
  43. break;
  44. case FUTEX_OP_ANDN:
  45. __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
  46. break;
  47. case FUTEX_OP_XOR:
  48. __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
  49. break;
  50. default:
  51. ret = -ENOSYS;
  52. }
  53. if (!ret)
  54. *oval = oldval;
  55. return ret;
  56. }
  57. static inline int
  58. futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  59. u32 oldval, u32 newval)
  60. {
  61. int ret = 0, cmp;
  62. u32 prev;
  63. if (!access_ok(uaddr, sizeof(u32)))
  64. return -EFAULT;
  65. __asm__ __volatile__ ("1: lwx %1, %3, r0; \
  66. cmp %2, %1, %4; \
  67. bnei %2, 3f; \
  68. 2: swx %5, %3, r0; \
  69. addic %2, r0, 0; \
  70. bnei %2, 1b; \
  71. 3: \
  72. .section .fixup,\"ax\"; \
  73. 4: brid 3b; \
  74. addik %0, r0, %6; \
  75. .previous; \
  76. .section __ex_table,\"a\"; \
  77. .word 1b,4b,2b,4b; \
  78. .previous;" \
  79. : "+r" (ret), "=&r" (prev), "=&r"(cmp) \
  80. : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));
  81. *uval = prev;
  82. return ret;
  83. }
  84. #endif /* __KERNEL__ */
  85. #endif