xref: /openbmc/linux/arch/xtensa/include/asm/syscall.h (revision 9fb29c73)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2001 - 2007 Tensilica Inc.
7  * Copyright (C) 2018 Cadence Design Systems Inc.
8  */
9 
10 #ifndef _ASM_SYSCALL_H
11 #define _ASM_SYSCALL_H
12 
13 #include <linux/err.h>
14 #include <asm/ptrace.h>
15 #include <uapi/linux/audit.h>
16 
17 static inline int syscall_get_arch(void)
18 {
19 	return AUDIT_ARCH_XTENSA;
20 }
21 
22 typedef void (*syscall_t)(void);
23 extern syscall_t sys_call_table[];
24 
25 static inline long syscall_get_nr(struct task_struct *task,
26 				  struct pt_regs *regs)
27 {
28 	return regs->syscall;
29 }
30 
31 static inline void syscall_rollback(struct task_struct *task,
32 				    struct pt_regs *regs)
33 {
34 	/* Do nothing. */
35 }
36 
37 static inline long syscall_get_error(struct task_struct *task,
38 				     struct pt_regs *regs)
39 {
40 	/* 0 if syscall succeeded, otherwise -Errorcode */
41 	return IS_ERR_VALUE(regs->areg[2]) ? regs->areg[2] : 0;
42 }
43 
44 static inline long syscall_get_return_value(struct task_struct *task,
45 					    struct pt_regs *regs)
46 {
47 	return regs->areg[2];
48 }
49 
50 static inline void syscall_set_return_value(struct task_struct *task,
51 					    struct pt_regs *regs,
52 					    int error, long val)
53 {
54 	regs->areg[0] = (long) error ? error : val;
55 }
56 
57 #define SYSCALL_MAX_ARGS 6
58 #define XTENSA_SYSCALL_ARGUMENT_REGS {6, 3, 4, 5, 8, 9}
59 
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 	static const unsigned int reg[] = XTENSA_SYSCALL_ARGUMENT_REGS;
66 	unsigned int j;
67 
68 	if (n == 0)
69 		return;
70 
71 	WARN_ON_ONCE(i + n > SYSCALL_MAX_ARGS);
72 
73 	for (j = 0; j < n; ++j) {
74 		if (i + j < SYSCALL_MAX_ARGS)
75 			args[j] = regs->areg[reg[i + j]];
76 		else
77 			args[j] = 0;
78 	}
79 }
80 
81 static inline void syscall_set_arguments(struct task_struct *task,
82 					 struct pt_regs *regs,
83 					 unsigned int i, unsigned int n,
84 					 const unsigned long *args)
85 {
86 	static const unsigned int reg[] = XTENSA_SYSCALL_ARGUMENT_REGS;
87 	unsigned int j;
88 
89 	if (n == 0)
90 		return;
91 
92 	if (WARN_ON_ONCE(i + n > SYSCALL_MAX_ARGS)) {
93 		if (i < SYSCALL_MAX_ARGS)
94 			n = SYSCALL_MAX_ARGS - i;
95 		else
96 			return;
97 	}
98 
99 	for (j = 0; j < n; ++j)
100 		regs->areg[reg[i + j]] = args[j];
101 }
102 
103 asmlinkage long xtensa_rt_sigreturn(struct pt_regs*);
104 asmlinkage long xtensa_shmat(int, char __user *, int);
105 asmlinkage long xtensa_fadvise64_64(int, int,
106 				    unsigned long long, unsigned long long);
107 
108 #endif
109