1 /* 2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 9 #ifndef _ASM_ARC_SYSCALL_H 10 #define _ASM_ARC_SYSCALL_H 1 11 12 #include <linux/err.h> 13 #include <linux/sched.h> 14 #include <asm/unistd.h> 15 #include <asm/ptrace.h> /* in_syscall() */ 16 17 static inline long 18 syscall_get_nr(struct task_struct *task, struct pt_regs *regs) 19 { 20 if (user_mode(regs) && in_syscall(regs)) 21 return regs->orig_r8; 22 else 23 return -1; 24 } 25 26 static inline void 27 syscall_rollback(struct task_struct *task, struct pt_regs *regs) 28 { 29 /* XXX: I can't fathom how pt_regs->r8 will be clobbered ? */ 30 regs->r8 = regs->orig_r8; 31 } 32 33 static inline long 34 syscall_get_error(struct task_struct *task, struct pt_regs *regs) 35 { 36 /* 0 if syscall succeeded, otherwise -Errorcode */ 37 return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0; 38 } 39 40 static inline long 41 syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) 42 { 43 return regs->r0; 44 } 45 46 static inline void 47 syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, 48 int error, long val) 49 { 50 regs->r0 = (long) error ?: val; 51 } 52 53 /* 54 * @i: argument index [0,5] 55 * @n: number of arguments; n+i must be [1,6]. 56 */ 57 static inline void 58 syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, 59 unsigned int i, unsigned int n, unsigned long *args) 60 { 61 unsigned long *inside_ptregs = &(regs->r0); 62 inside_ptregs -= i; 63 64 BUG_ON((i + n) > 6); 65 66 while (n--) { 67 args[i++] = (*inside_ptregs); 68 inside_ptregs--; 69 } 70 } 71 72 #endif 73