LXR linux/arch/um/include/asm/syscall-generic.h

   1/*
   2 * Access to user system call parameters and results
   3 *
   4 * See asm-generic/syscall.h for function descriptions.
   5 *
   6 * Copyright (C) 2015 Mickaël Salaün <mic@digikod.net>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#ifndef __UM_SYSCALL_GENERIC_H
  14#define __UM_SYSCALL_GENERIC_H
  15
  16#include <asm/ptrace.h>
  17#include <linux/err.h>
  18#include <linux/sched.h>
  19#include <sysdep/ptrace.h>
  20
  21static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
  22{
  23
  24        return PT_REGS_SYSCALL_NR(regs);
  25}
  26
  27static inline void syscall_rollback(struct task_struct *task,
  28                                    struct pt_regs *regs)
  29{
  30        /* do nothing */
  31}
  32
  33static inline long syscall_get_error(struct task_struct *task,
  34                                     struct pt_regs *regs)
  35{
  36        const long error = regs_return_value(regs);
  37
  38        return IS_ERR_VALUE(error) ? error : 0;
  39}
  40
  41static inline long syscall_get_return_value(struct task_struct *task,
  42                                            struct pt_regs *regs)
  43{
  44        return regs_return_value(regs);
  45}
  46
  47static inline void syscall_set_return_value(struct task_struct *task,
  48                                            struct pt_regs *regs,
  49                                            int error, long val)
  50{
  51        PT_REGS_SET_SYSCALL_RETURN(regs, (long) error ?: val);
  52}
  53
  54static inline void syscall_get_arguments(struct task_struct *task,
  55                                         struct pt_regs *regs,
  56                                         unsigned int i, unsigned int n,
  57                                         unsigned long *args)
  58{
  59        const struct uml_pt_regs *r = &regs->regs;
  60
  61        switch (i) {
  62        case 0:
  63                if (!n--)
  64                        break;
  65                *args++ = UPT_SYSCALL_ARG1(r);
  66        case 1:
  67                if (!n--)
  68                        break;
  69                *args++ = UPT_SYSCALL_ARG2(r);
  70        case 2:
  71                if (!n--)
  72                        break;
  73                *args++ = UPT_SYSCALL_ARG3(r);
  74        case 3:
  75                if (!n--)
  76                        break;
  77                *args++ = UPT_SYSCALL_ARG4(r);
  78        case 4:
  79                if (!n--)
  80                        break;
  81                *args++ = UPT_SYSCALL_ARG5(r);
  82        case 5:
  83                if (!n--)
  84                        break;
  85                *args++ = UPT_SYSCALL_ARG6(r);
  86        case 6:
  87                if (!n--)
  88                        break;
  89        default:
  90                BUG();
  91                break;
  92        }
  93}
  94
  95static inline void syscall_set_arguments(struct task_struct *task,
  96                                         struct pt_regs *regs,
  97                                         unsigned int i, unsigned int n,
  98                                         const unsigned long *args)
  99{
 100        struct uml_pt_regs *r = &regs->regs;
 101
 102        switch (i) {
 103        case 0:
 104                if (!n--)
 105                        break;
 106                UPT_SYSCALL_ARG1(r) = *args++;
 107        case 1:
 108                if (!n--)
 109                        break;
 110                UPT_SYSCALL_ARG2(r) = *args++;
 111        case 2:
 112                if (!n--)
 113                        break;
 114                UPT_SYSCALL_ARG3(r) = *args++;
 115        case 3:
 116                if (!n--)
 117                        break;
 118                UPT_SYSCALL_ARG4(r) = *args++;
 119        case 4:
 120                if (!n--)
 121                        break;
 122                UPT_SYSCALL_ARG5(r) = *args++;
 123        case 5:
 124                if (!n--)
 125                        break;
 126                UPT_SYSCALL_ARG6(r) = *args++;
 127        case 6:
 128                if (!n--)
 129                        break;
 130        default:
 131                BUG();
 132                break;
 133        }
 134}
 135
 136/* See arch/x86/um/asm/syscall.h for syscall_get_arch() definition. */
 137
 138#endif  /* __UM_SYSCALL_GENERIC_H */
 139