xref: /openbmc/linux/arch/riscv/include/asm/syscall.h (revision 6562c9ac)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2008-2009 Red Hat, Inc.  All rights reserved.
4  * Copyright 2010 Tilera Corporation. All Rights Reserved.
5  * Copyright 2015 Regents of the University of California, Berkeley
6  *
7  * See asm-generic/syscall.h for descriptions of what we must do here.
8  */
9 
10 #ifndef _ASM_RISCV_SYSCALL_H
11 #define _ASM_RISCV_SYSCALL_H
12 
13 #include <uapi/linux/audit.h>
14 #include <linux/sched.h>
15 #include <linux/err.h>
16 
17 /* The array of function pointers for syscalls. */
18 extern void * const sys_call_table[];
19 extern void * const compat_sys_call_table[];
20 
21 /*
22  * Only the low 32 bits of orig_r0 are meaningful, so we return int.
23  * This importantly ignores the high bits on 64-bit, so comparisons
24  * sign-extend the low 32 bits.
25  */
26 static inline int syscall_get_nr(struct task_struct *task,
27 				 struct pt_regs *regs)
28 {
29 	return regs->a7;
30 }
31 
32 static inline void syscall_rollback(struct task_struct *task,
33 				    struct pt_regs *regs)
34 {
35         regs->a0 = regs->orig_a0;
36 }
37 
38 static inline long syscall_get_error(struct task_struct *task,
39 				     struct pt_regs *regs)
40 {
41 	unsigned long error = regs->a0;
42 
43 	return IS_ERR_VALUE(error) ? error : 0;
44 }
45 
46 static inline long syscall_get_return_value(struct task_struct *task,
47 					    struct pt_regs *regs)
48 {
49 	return regs->a0;
50 }
51 
52 static inline void syscall_set_return_value(struct task_struct *task,
53 					    struct pt_regs *regs,
54 					    int error, long val)
55 {
56 	regs->a0 = (long) error ?: val;
57 }
58 
59 static inline void syscall_get_arguments(struct task_struct *task,
60 					 struct pt_regs *regs,
61 					 unsigned long *args)
62 {
63 	args[0] = regs->orig_a0;
64 	args++;
65 	memcpy(args, &regs->a1, 5 * sizeof(args[0]));
66 }
67 
68 static inline int syscall_get_arch(struct task_struct *task)
69 {
70 #ifdef CONFIG_64BIT
71 	return AUDIT_ARCH_RISCV64;
72 #else
73 	return AUDIT_ARCH_RISCV32;
74 #endif
75 }
76 
77 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
78 #endif	/* _ASM_RISCV_SYSCALL_H */
79