/arch/powerpc/include/asm/syscall.h

 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, &regs->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(&regs->gpr[3 + i], args, n * sizeof(args[0]));
82}
83
84#endif	/* _ASM_SYSCALL_H */