LXR linux/arch/tile/include/asm/syscall.h

   1/*
   2 * Copyright (C) 2008-2009 Red Hat, Inc.  All rights reserved.
   3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
   4 *
   5 *   This program is free software; you can redistribute it and/or
   6 *   modify it under the terms of the GNU General Public License
   7 *   as published by the Free Software Foundation, version 2.
   8 *
   9 *   This program is distributed in the hope that it will be useful, but
  10 *   WITHOUT ANY WARRANTY; without even the implied warranty of
  11 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  12 *   NON INFRINGEMENT.  See the GNU General Public License for
  13 *   more details.
  14 *
  15 * See asm-generic/syscall.h for descriptions of what we must do here.
  16 */
  17
  18#ifndef _ASM_TILE_SYSCALL_H
  19#define _ASM_TILE_SYSCALL_H
  20
  21#include <linux/sched.h>
  22#include <linux/err.h>
  23#include <arch/abi.h>
  24
  25/* The array of function pointers for syscalls. */
  26extern void *sys_call_table[];
  27#ifdef CONFIG_COMPAT
  28extern void *compat_sys_call_table[];
  29#endif
  30
  31/*
  32 * Only the low 32 bits of orig_r0 are meaningful, so we return int.
  33 * This importantly ignores the high bits on 64-bit, so comparisons
  34 * sign-extend the low 32 bits.
  35 */
  36static inline int syscall_get_nr(struct task_struct *t, struct pt_regs *regs)
  37{
  38        return regs->regs[TREG_SYSCALL_NR];
  39}
  40
  41static inline void syscall_rollback(struct task_struct *task,
  42                                    struct pt_regs *regs)
  43{
  44        regs->regs[0] = regs->orig_r0;
  45}
  46
  47static inline long syscall_get_error(struct task_struct *task,
  48                                     struct pt_regs *regs)
  49{
  50        unsigned long error = regs->regs[0];
  51        return IS_ERR_VALUE(error) ? error : 0;
  52}
  53
  54static inline long syscall_get_return_value(struct task_struct *task,
  55                                            struct pt_regs *regs)
  56{
  57        return regs->regs[0];
  58}
  59
  60static inline void syscall_set_return_value(struct task_struct *task,
  61                                            struct pt_regs *regs,
  62                                            int error, long val)
  63{
  64        regs->regs[0] = (long) error ?: val;
  65}
  66
  67static inline void syscall_get_arguments(struct task_struct *task,
  68                                         struct pt_regs *regs,
  69                                         unsigned int i, unsigned int n,
  70                                         unsigned long *args)
  71{
  72        BUG_ON(i + n > 6);
  73        memcpy(args, &regs[i], n * sizeof(args[0]));
  74}
  75
  76static inline void syscall_set_arguments(struct task_struct *task,
  77                                         struct pt_regs *regs,
  78                                         unsigned int i, unsigned int n,
  79                                         const unsigned long *args)
  80{
  81        BUG_ON(i + n > 6);
  82        memcpy(&regs[i], args, n * sizeof(args[0]));
  83}
  84
  85#endif  /* _ASM_TILE_SYSCALL_H */
  86