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 /*
  18  * The syscall table always contains 32 bit pointers since we know that the
  19  * address of the function to be called is (way) below 4GB.  So the "int"
  20  * type here is what we want [need] for both 32 bit and 64 bit systems.
  21  */
  22 extern const unsigned int sys_call_table[];
  23 extern const unsigned int sys_call_table_emu[];
  24
  25 static inline long syscall_get_nr(struct task_struct *task,
  26                                   struct pt_regs *regs)
  27 {
  28         return test_pt_regs_flag(regs, PIF_SYSCALL) ?
  29                 (regs->int_code & 0xffff) : -1;
  30 }
  31
  32 static inline void syscall_rollback(struct task_struct *task,
  33                                     struct pt_regs *regs)
  34 {
  35         regs->gprs[2] = regs->orig_gpr2;
  36 }
  37
  38 static inline long syscall_get_error(struct task_struct *task,
  39                                      struct pt_regs *regs)
  40 {
  41         return IS_ERR_VALUE(regs->gprs[2]) ? regs->gprs[2] : 0;
  42 }
  43
  44 static inline long syscall_get_return_value(struct task_struct *task,
  45                                             struct pt_regs *regs)
  46 {
  47         return regs->gprs[2];
  48 }
  49
  50 static inline void syscall_set_return_value(struct task_struct *task,
  51                                             struct pt_regs *regs,
  52                                             int error, long val)
  53 {
  54         regs->gprs[2] = error ? error : val;
  55 }
  56
  57 static inline void syscall_get_arguments(struct task_struct *task,
  58                                          struct pt_regs *regs,
  59                                          unsigned int i, unsigned int n,
  60                                          unsigned long *args)
  61 {
  62         unsigned long mask = -1UL;
  63
  64         /*
  65          * No arguments for this syscall, there's nothing to do.
  66          */
  67         if (!n)
  68                 return;
  69
  70         BUG_ON(i + n > 6);
  71 #ifdef CONFIG_COMPAT
  72         if (test_tsk_thread_flag(task, TIF_31BIT))
  73                 mask = 0xffffffff;
  74 #endif
  75         while (n-- > 0)
  76                 if (i + n > 0)
  77                         args[n] = regs->gprs[2 + i + n] & mask;
  78         if (i == 0)
  79                 args[0] = regs->orig_gpr2 & mask;
  80 }
  81
  82 static inline void syscall_set_arguments(struct task_struct *task,
  83                                          struct pt_regs *regs,
  84                                          unsigned int i, unsigned int n,
  85                                          const unsigned long *args)
  86 {
  87         BUG_ON(i + n > 6);
  88         while (n-- > 0)
  89                 if (i + n > 0)
  90                         regs->gprs[2 + i + n] = args[n];
  91         if (i == 0)
  92                 regs->orig_gpr2 = args[0];
  93 }
  94
  95 static inline int syscall_get_arch(void)
  96 {
  97 #ifdef CONFIG_COMPAT
  98         if (test_tsk_thread_flag(current, TIF_31BIT))
  99                 return AUDIT_ARCH_S390;
 100 #endif
 101         return AUDIT_ARCH_S390X;
 102 }
 103 #endif  /* _ASM_SYSCALL_H */