futex.h 1.3 KB

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  1. #ifndef _ASM_GENERIC_FUTEX_H
  2. #define _ASM_GENERIC_FUTEX_H
  3. #ifdef __KERNEL__
  4. #include <linux/futex.h>
  5. #include <asm/errno.h>
  6. #include <asm/uaccess.h>
  7. static inline int
  8. futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
  9. {
  10. int op = (encoded_op >> 28) & 7;
  11. int cmp = (encoded_op >> 24) & 15;
  12. int oparg = (encoded_op << 8) >> 20;
  13. int cmparg = (encoded_op << 20) >> 20;
  14. int oldval = 0, ret;
  15. if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
  16. oparg = 1 << oparg;
  17. if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
  18. return -EFAULT;
  19. pagefault_disable();
  20. switch (op) {
  21. case FUTEX_OP_SET:
  22. case FUTEX_OP_ADD:
  23. case FUTEX_OP_OR:
  24. case FUTEX_OP_ANDN:
  25. case FUTEX_OP_XOR:
  26. default:
  27. ret = -ENOSYS;
  28. }
  29. pagefault_enable();
  30. if (!ret) {
  31. switch (cmp) {
  32. case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
  33. case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
  34. case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
  35. case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
  36. case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
  37. case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
  38. default: ret = -ENOSYS;
  39. }
  40. }
  41. return ret;
  42. }
  43. static inline int
  44. futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
  45. {
  46. return -ENOSYS;
  47. }
  48. #endif
  49. #endif