1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Access to user system call parameters and results
4  *
5  * See asm-generic/syscall.h for function descriptions.
6  *
7  * Copyright (C) 2015 Mickaël Salaün <mic@digikod.net>
8  */
9 
10 #ifndef __UM_SYSCALL_GENERIC_H
11 #define __UM_SYSCALL_GENERIC_H
12 
13 #include <asm/ptrace.h>
14 #include <linux/err.h>
15 #include <linux/sched.h>
16 #include <sysdep/ptrace.h>
17 
18 static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
19 {
20 
21 	return PT_REGS_SYSCALL_NR(regs);
22 }
23 
24 static inline void syscall_rollback(struct task_struct *task,
25 				    struct pt_regs *regs)
26 {
27 	/* do nothing */
28 }
29 
30 static inline long syscall_get_error(struct task_struct *task,
31 				     struct pt_regs *regs)
32 {
33 	const long error = regs_return_value(regs);
34 
35 	return IS_ERR_VALUE(error) ? error : 0;
36 }
37 
38 static inline long syscall_get_return_value(struct task_struct *task,
39 					    struct pt_regs *regs)
40 {
41 	return regs_return_value(regs);
42 }
43 
44 static inline void syscall_set_return_value(struct task_struct *task,
45 					    struct pt_regs *regs,
46 					    int error, long val)
47 {
48 	PT_REGS_SET_SYSCALL_RETURN(regs, (long) error ?: val);
49 }
50 
51 static inline void syscall_get_arguments(struct task_struct *task,
52 					 struct pt_regs *regs,
53 					 unsigned long *args)
54 {
55 	const struct uml_pt_regs *r = &regs->regs;
56 
57 	*args++ = UPT_SYSCALL_ARG1(r);
58 	*args++ = UPT_SYSCALL_ARG2(r);
59 	*args++ = UPT_SYSCALL_ARG3(r);
60 	*args++ = UPT_SYSCALL_ARG4(r);
61 	*args++ = UPT_SYSCALL_ARG5(r);
62 	*args   = UPT_SYSCALL_ARG6(r);
63 }
64 
65 static inline void syscall_set_arguments(struct task_struct *task,
66 					 struct pt_regs *regs,
67 					 const unsigned long *args)
68 {
69 	struct uml_pt_regs *r = &regs->regs;
70 
71 	UPT_SYSCALL_ARG1(r) = *args++;
72 	UPT_SYSCALL_ARG2(r) = *args++;
73 	UPT_SYSCALL_ARG3(r) = *args++;
74 	UPT_SYSCALL_ARG4(r) = *args++;
75 	UPT_SYSCALL_ARG5(r) = *args++;
76 	UPT_SYSCALL_ARG6(r) = *args;
77 }
78 
79 /* See arch/x86/um/asm/syscall.h for syscall_get_arch() definition. */
80 
81 #endif	/* __UM_SYSCALL_GENERIC_H */
82