1/* 2 * Access to user system call parameters and results 3 * 4 * Copyright (C) 2008 Red Hat, Inc. All rights reserved. 5 * 6 * This copyrighted material is made available to anyone wishing to use, 7 * modify, copy, or redistribute it subject to the terms and conditions 8 * of the GNU General Public License v.2. 9 * 10 * See asm-generic/syscall.h for descriptions of what we must do here. 11 */ 12 13#ifndef _ASM_SYSCALL_H 14#define _ASM_SYSCALL_H 1 15 16#include <linux/sched.h> 17 18static inline long syscall_get_nr(struct task_struct *task, 19 struct pt_regs *regs) 20{ 21 return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L; 22} 23 24static inline void syscall_rollback(struct task_struct *task, 25 struct pt_regs *regs) 26{ 27 regs->gpr[3] = regs->orig_gpr3; 28} 29 30static inline long syscall_get_error(struct task_struct *task, 31 struct pt_regs *regs) 32{ 33 return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0; 34} 35 36static inline long syscall_get_return_value(struct task_struct *task, 37 struct pt_regs *regs) 38{ 39 return regs->gpr[3]; 40} 41 42static inline void syscall_set_return_value(struct task_struct *task, 43 struct pt_regs *regs, 44 int error, long val) 45{ 46 if (error) { 47 regs->ccr |= 0x10000000L; 48 regs->gpr[3] = -error; 49 } else { 50 regs->ccr &= ~0x10000000L; 51 regs->gpr[3] = val; 52 } 53} 54 55static inline void syscall_get_arguments(struct task_struct *task, 56 struct pt_regs *regs, 57 unsigned int i, unsigned int n, 58 unsigned long *args) 59{ 60 BUG_ON(i + n > 6); 61#ifdef CONFIG_PPC64 62 if (test_tsk_thread_flag(task, TIF_32BIT)) { 63 /* 64 * Zero-extend 32-bit argument values. The high bits are 65 * garbage ignored by the actual syscall dispatch. 66 */ 67 while (n-- > 0) 68 args[n] = (u32) regs->gpr[3 + i + n]; 69 return; 70 } 71#endif 72 memcpy(args, ®s->gpr[3 + i], n * sizeof(args[0])); 73} 74 75static inline void syscall_set_arguments(struct task_struct *task, 76 struct pt_regs *regs, 77 unsigned int i, unsigned int n, 78 const unsigned long *args) 79{ 80 BUG_ON(i + n > 6); 81 memcpy(®s->gpr[3 + i], args, n * sizeof(args[0])); 82} 83 84#endif /* _ASM_SYSCALL_H */ 85