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
18 /* ftrace syscalls requires exporting the sys_call_table */
19 #ifdef CONFIG_FTRACE_SYSCALLS
20 extern const unsigned long *sys_call_table;
21 #endif /* CONFIG_FTRACE_SYSCALLS */
22
syscall_get_nr(struct task_struct * task,struct pt_regs * regs)23 static inline long syscall_get_nr(struct task_struct *task,
24 struct pt_regs *regs)
25 {
26 return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L;
27 }
28
syscall_rollback(struct task_struct * task,struct pt_regs * regs)29 static inline void syscall_rollback(struct task_struct *task,
30 struct pt_regs *regs)
31 {
32 regs->gpr[3] = regs->orig_gpr3;
33 }
34
syscall_get_error(struct task_struct * task,struct pt_regs * regs)35 static inline long syscall_get_error(struct task_struct *task,
36 struct pt_regs *regs)
37 {
38 return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0;
39 }
40
syscall_get_return_value(struct task_struct * task,struct pt_regs * regs)41 static inline long syscall_get_return_value(struct task_struct *task,
42 struct pt_regs *regs)
43 {
44 return regs->gpr[3];
45 }
46
syscall_set_return_value(struct task_struct * task,struct pt_regs * regs,int error,long val)47 static inline void syscall_set_return_value(struct task_struct *task,
48 struct pt_regs *regs,
49 int error, long val)
50 {
51 if (error) {
52 regs->ccr |= 0x10000000L;
53 regs->gpr[3] = -error;
54 } else {
55 regs->ccr &= ~0x10000000L;
56 regs->gpr[3] = val;
57 }
58 }
59
syscall_get_arguments(struct task_struct * task,struct pt_regs * regs,unsigned int i,unsigned int n,unsigned long * args)60 static inline void syscall_get_arguments(struct task_struct *task,
61 struct pt_regs *regs,
62 unsigned int i, unsigned int n,
63 unsigned long *args)
64 {
65 BUG_ON(i + n > 6);
66 #ifdef CONFIG_PPC64
67 if (test_tsk_thread_flag(task, TIF_32BIT)) {
68 /*
69 * Zero-extend 32-bit argument values. The high bits are
70 * garbage ignored by the actual syscall dispatch.
71 */
72 while (n-- > 0)
73 args[n] = (u32) regs->gpr[3 + i + n];
74 return;
75 }
76 #endif
77 memcpy(args, ®s->gpr[3 + i], n * sizeof(args[0]));
78 }
79
syscall_set_arguments(struct task_struct * task,struct pt_regs * regs,unsigned int i,unsigned int n,const unsigned long * args)80 static inline void syscall_set_arguments(struct task_struct *task,
81 struct pt_regs *regs,
82 unsigned int i, unsigned int n,
83 const unsigned long *args)
84 {
85 BUG_ON(i + n > 6);
86 memcpy(®s->gpr[3 + i], args, n * sizeof(args[0]));
87 }
88
89 #endif /* _ASM_SYSCALL_H */
90