xref: /linux/arch/arm/include/asm/syscall.h (revision 5c61ee2cd5860e41c8ab98837761ffaa93eb4dfe)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Access to user system call parameters and results
4  *
5  * See asm-generic/syscall.h for descriptions of what we must do here.
6  */
7 
8 #ifndef _ASM_ARM_SYSCALL_H
9 #define _ASM_ARM_SYSCALL_H
10 
11 #include <uapi/linux/audit.h> /* for AUDIT_ARCH_* */
12 #include <linux/elf.h> /* for ELF_EM */
13 #include <linux/err.h>
14 #include <linux/sched.h>
15 
16 #include <asm/unistd.h>
17 
18 #define NR_syscalls (__NR_syscalls)
19 
20 extern const unsigned long sys_call_table[];
21 
22 static inline int syscall_get_nr(struct task_struct *task,
23 				 struct pt_regs *regs)
24 {
25 	return task_thread_info(task)->syscall;
26 }
27 
28 static inline void syscall_rollback(struct task_struct *task,
29 				    struct pt_regs *regs)
30 {
31 	regs->ARM_r0 = regs->ARM_ORIG_r0;
32 }
33 
34 static inline long syscall_get_error(struct task_struct *task,
35 				     struct pt_regs *regs)
36 {
37 	unsigned long error = regs->ARM_r0;
38 	return IS_ERR_VALUE(error) ? error : 0;
39 }
40 
41 static inline long syscall_get_return_value(struct task_struct *task,
42 					    struct pt_regs *regs)
43 {
44 	return regs->ARM_r0;
45 }
46 
47 static inline void syscall_set_return_value(struct task_struct *task,
48 					    struct pt_regs *regs,
49 					    int error, long val)
50 {
51 	regs->ARM_r0 = (long) error ? error : val;
52 }
53 
54 #define SYSCALL_MAX_ARGS 7
55 
56 static inline void syscall_get_arguments(struct task_struct *task,
57 					 struct pt_regs *regs,
58 					 unsigned long *args)
59 {
60 	args[0] = regs->ARM_ORIG_r0;
61 	args++;
62 
63 	memcpy(args, &regs->ARM_r0 + 1, 5 * sizeof(args[0]));
64 }
65 
66 static inline void syscall_set_arguments(struct task_struct *task,
67 					 struct pt_regs *regs,
68 					 const unsigned long *args)
69 {
70 	regs->ARM_ORIG_r0 = args[0];
71 	args++;
72 
73 	memcpy(&regs->ARM_r0 + 1, args, 5 * sizeof(args[0]));
74 }
75 
76 static inline int syscall_get_arch(void)
77 {
78 	/* ARM tasks don't change audit architectures on the fly. */
79 	return AUDIT_ARCH_ARM;
80 }
81 
82 #endif /* _ASM_ARM_SYSCALL_H */
83