arch/s390/include/asm/syscall.h

   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 (schwidefsky@de.ibm.com)
   7  */
   8
   9 #ifndef _ASM_SYSCALL_H
  10 #define _ASM_SYSCALL_H  1
  11
  12 #include <uapi/linux/audit.h>
  13 #include <linux/sched.h>
  14 #include <linux/err.h>
  15 #include <asm/ptrace.h>
  16
  17 extern const unsigned long sys_call_table[];
  18 extern const unsigned long sys_call_table_emu[];
  19
  20 static inline long syscall_get_nr(struct task_struct *task,
  21                                   struct pt_regs *regs)
  22 {
  23         return test_pt_regs_flag(regs, PIF_SYSCALL) ?
  24                 (regs->int_code & 0xffff) : -1;
  25 }
  26
  27 static inline void syscall_rollback(struct task_struct *task,
  28                                     struct pt_regs *regs)
  29 {
  30         regs->gprs[2] = regs->orig_gpr2;
  31 }
  32
  33 static inline long syscall_get_error(struct task_struct *task,
  34                                      struct pt_regs *regs)
  35 {
  36         unsigned long error = regs->gprs[2];
  37 #ifdef CONFIG_COMPAT
  38         if (test_tsk_thread_flag(task, TIF_31BIT)) {
  39                 /*
  40                  * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
  41                  * and will match correctly in comparisons.
  42                  */
  43                 error = (long)(int)error;
  44         }
  45 #endif
  46         return IS_ERR_VALUE(error) ? error : 0;
  47 }
  48
  49 static inline long syscall_get_return_value(struct task_struct *task,
  50                                             struct pt_regs *regs)
  51 {
  52         return regs->gprs[2];
  53 }
  54
  55 static inline void syscall_set_return_value(struct task_struct *task,
  56                                             struct pt_regs *regs,
  57                                             int error, long val)
  58 {
  59         regs->gprs[2] = error ? error : val;
  60 }
  61
  62 static inline void syscall_get_arguments(struct task_struct *task,
  63                                          struct pt_regs *regs,
  64                                          unsigned long *args)
  65 {
  66         unsigned long mask = -1UL;
  67         unsigned int n = 6;
  68
  69 #ifdef CONFIG_COMPAT
  70         if (test_tsk_thread_flag(task, TIF_31BIT))
  71                 mask = 0xffffffff;
  72 #endif
  73         while (n-- > 0)
  74                 if (n > 0)
  75                         args[n] = regs->gprs[2 + n] & mask;
  76
  77         args[0] = regs->orig_gpr2 & mask;
  78 }
  79
  80 static inline void syscall_set_arguments(struct task_struct *task,
  81                                          struct pt_regs *regs,
  82                                          const unsigned long *args)
  83 {
  84         unsigned int n = 6;
  85
  86         while (n-- > 0)
  87                 if (n > 0)
  88                         regs->gprs[2 + n] = args[n];
  89         regs->orig_gpr2 = args[0];
  90 }
  91
  92 static inline int syscall_get_arch(struct task_struct *task)
  93 {
  94 #ifdef CONFIG_COMPAT
  95         if (test_tsk_thread_flag(task, TIF_31BIT))
  96                 return AUDIT_ARCH_S390;
  97 #endif
  98         return AUDIT_ARCH_S390X;
  99 }
 100 #endif  /* _ASM_SYSCALL_H */