syscall.h 3.8 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154
  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /*
  3. * Access to user system call parameters and results
  4. *
  5. * Copyright IBM Corp. 2008
  6. * Author(s): Martin Schwidefsky ([email protected])
  7. */
  8. #ifndef _ASM_SYSCALL_H
  9. #define _ASM_SYSCALL_H 1
  10. #include <uapi/linux/audit.h>
  11. #include <linux/sched.h>
  12. #include <linux/err.h>
  13. #include <asm/ptrace.h>
  14. extern const sys_call_ptr_t sys_call_table[];
  15. extern const sys_call_ptr_t sys_call_table_emu[];
  16. static inline long syscall_get_nr(struct task_struct *task,
  17. struct pt_regs *regs)
  18. {
  19. return test_pt_regs_flag(regs, PIF_SYSCALL) ?
  20. (regs->int_code & 0xffff) : -1;
  21. }
  22. static inline void syscall_rollback(struct task_struct *task,
  23. struct pt_regs *regs)
  24. {
  25. regs->gprs[2] = regs->orig_gpr2;
  26. }
  27. static inline long syscall_get_error(struct task_struct *task,
  28. struct pt_regs *regs)
  29. {
  30. unsigned long error = regs->gprs[2];
  31. #ifdef CONFIG_COMPAT
  32. if (test_tsk_thread_flag(task, TIF_31BIT)) {
  33. /*
  34. * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
  35. * and will match correctly in comparisons.
  36. */
  37. error = (long)(int)error;
  38. }
  39. #endif
  40. return IS_ERR_VALUE(error) ? error : 0;
  41. }
  42. static inline long syscall_get_return_value(struct task_struct *task,
  43. struct pt_regs *regs)
  44. {
  45. return regs->gprs[2];
  46. }
  47. static inline void syscall_set_return_value(struct task_struct *task,
  48. struct pt_regs *regs,
  49. int error, long val)
  50. {
  51. set_pt_regs_flag(regs, PIF_SYSCALL_RET_SET);
  52. regs->gprs[2] = error ? error : val;
  53. }
  54. static inline void syscall_get_arguments(struct task_struct *task,
  55. struct pt_regs *regs,
  56. unsigned long *args)
  57. {
  58. unsigned long mask = -1UL;
  59. unsigned int n = 6;
  60. #ifdef CONFIG_COMPAT
  61. if (test_tsk_thread_flag(task, TIF_31BIT))
  62. mask = 0xffffffff;
  63. #endif
  64. while (n-- > 0)
  65. if (n > 0)
  66. args[n] = regs->gprs[2 + n] & mask;
  67. args[0] = regs->orig_gpr2 & mask;
  68. }
  69. static inline int syscall_get_arch(struct task_struct *task)
  70. {
  71. #ifdef CONFIG_COMPAT
  72. if (test_tsk_thread_flag(task, TIF_31BIT))
  73. return AUDIT_ARCH_S390;
  74. #endif
  75. return AUDIT_ARCH_S390X;
  76. }
  77. static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
  78. {
  79. return false;
  80. }
  81. #define SYSCALL_FMT_0
  82. #define SYSCALL_FMT_1 , "0" (r2)
  83. #define SYSCALL_FMT_2 , "d" (r3) SYSCALL_FMT_1
  84. #define SYSCALL_FMT_3 , "d" (r4) SYSCALL_FMT_2
  85. #define SYSCALL_FMT_4 , "d" (r5) SYSCALL_FMT_3
  86. #define SYSCALL_FMT_5 , "d" (r6) SYSCALL_FMT_4
  87. #define SYSCALL_FMT_6 , "d" (r7) SYSCALL_FMT_5
  88. #define SYSCALL_PARM_0
  89. #define SYSCALL_PARM_1 , long arg1
  90. #define SYSCALL_PARM_2 SYSCALL_PARM_1, long arg2
  91. #define SYSCALL_PARM_3 SYSCALL_PARM_2, long arg3
  92. #define SYSCALL_PARM_4 SYSCALL_PARM_3, long arg4
  93. #define SYSCALL_PARM_5 SYSCALL_PARM_4, long arg5
  94. #define SYSCALL_PARM_6 SYSCALL_PARM_5, long arg6
  95. #define SYSCALL_REGS_0
  96. #define SYSCALL_REGS_1 \
  97. register long r2 asm("2") = arg1
  98. #define SYSCALL_REGS_2 \
  99. SYSCALL_REGS_1; \
  100. register long r3 asm("3") = arg2
  101. #define SYSCALL_REGS_3 \
  102. SYSCALL_REGS_2; \
  103. register long r4 asm("4") = arg3
  104. #define SYSCALL_REGS_4 \
  105. SYSCALL_REGS_3; \
  106. register long r5 asm("5") = arg4
  107. #define SYSCALL_REGS_5 \
  108. SYSCALL_REGS_4; \
  109. register long r6 asm("6") = arg5
  110. #define SYSCALL_REGS_6 \
  111. SYSCALL_REGS_5; \
  112. register long r7 asm("7") = arg6
  113. #define GENERATE_SYSCALL_FUNC(nr) \
  114. static __always_inline \
  115. long syscall##nr(unsigned long syscall SYSCALL_PARM_##nr) \
  116. { \
  117. register unsigned long r1 asm ("1") = syscall; \
  118. register long rc asm ("2"); \
  119. SYSCALL_REGS_##nr; \
  120. \
  121. asm volatile ( \
  122. " svc 0\n" \
  123. : "=d" (rc) \
  124. : "d" (r1) SYSCALL_FMT_##nr \
  125. : "memory"); \
  126. return rc; \
  127. }
  128. GENERATE_SYSCALL_FUNC(0)
  129. GENERATE_SYSCALL_FUNC(1)
  130. GENERATE_SYSCALL_FUNC(2)
  131. GENERATE_SYSCALL_FUNC(3)
  132. GENERATE_SYSCALL_FUNC(4)
  133. GENERATE_SYSCALL_FUNC(5)
  134. GENERATE_SYSCALL_FUNC(6)
  135. #endif /* _ASM_SYSCALL_H */