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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Access to user system call parameters and results
4 *
5 * Copyright IBM Corp. 2008
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
7 */
8
9#ifndef _ASM_SYSCALL_H
10#define _ASM_SYSCALL_H 1
11
12#include <uapi/linux/audit.h>
13#include <linux/sched.h>
14#include <linux/err.h>
15#include <asm/ptrace.h>
16
17extern const sys_call_ptr_t sys_call_table[];
18extern const sys_call_ptr_t sys_call_table_emu[];
19
20static inline long syscall_get_nr(struct task_struct *task,
21 struct pt_regs *regs)
22{
23 return test_pt_regs_flag(regs, PIF_SYSCALL) ?
24 (regs->int_code & 0xffff) : -1;
25}
26
27static inline void syscall_rollback(struct task_struct *task,
28 struct pt_regs *regs)
29{
30 regs->gprs[2] = regs->orig_gpr2;
31}
32
33static inline long syscall_get_error(struct task_struct *task,
34 struct pt_regs *regs)
35{
36 unsigned long error = regs->gprs[2];
37#ifdef CONFIG_COMPAT
38 if (test_tsk_thread_flag(task, TIF_31BIT)) {
39 /*
40 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
41 * and will match correctly in comparisons.
42 */
43 error = (long)(int)error;
44 }
45#endif
46 return IS_ERR_VALUE(error) ? error : 0;
47}
48
49static inline long syscall_get_return_value(struct task_struct *task,
50 struct pt_regs *regs)
51{
52 return regs->gprs[2];
53}
54
55static inline void syscall_set_return_value(struct task_struct *task,
56 struct pt_regs *regs,
57 int error, long val)
58{
59 set_pt_regs_flag(regs, PIF_SYSCALL_RET_SET);
60 regs->gprs[2] = error ? error : val;
61}
62
63static inline void syscall_get_arguments(struct task_struct *task,
64 struct pt_regs *regs,
65 unsigned long *args)
66{
67 unsigned long mask = -1UL;
68 unsigned int n = 6;
69
70#ifdef CONFIG_COMPAT
71 if (test_tsk_thread_flag(task, TIF_31BIT))
72 mask = 0xffffffff;
73#endif
74 while (n-- > 0)
75 if (n > 0)
76 args[n] = regs->gprs[2 + n] & mask;
77
78 args[0] = regs->orig_gpr2 & mask;
79}
80
81static inline int syscall_get_arch(struct task_struct *task)
82{
83#ifdef CONFIG_COMPAT
84 if (test_tsk_thread_flag(task, TIF_31BIT))
85 return AUDIT_ARCH_S390;
86#endif
87 return AUDIT_ARCH_S390X;
88}
89
90static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
91{
92 return false;
93}
94
95#define SYSCALL_FMT_0
96#define SYSCALL_FMT_1 , "0" (r2)
97#define SYSCALL_FMT_2 , "d" (r3) SYSCALL_FMT_1
98#define SYSCALL_FMT_3 , "d" (r4) SYSCALL_FMT_2
99#define SYSCALL_FMT_4 , "d" (r5) SYSCALL_FMT_3
100#define SYSCALL_FMT_5 , "d" (r6) SYSCALL_FMT_4
101#define SYSCALL_FMT_6 , "d" (r7) SYSCALL_FMT_5
102
103#define SYSCALL_PARM_0
104#define SYSCALL_PARM_1 , long arg1
105#define SYSCALL_PARM_2 SYSCALL_PARM_1, long arg2
106#define SYSCALL_PARM_3 SYSCALL_PARM_2, long arg3
107#define SYSCALL_PARM_4 SYSCALL_PARM_3, long arg4
108#define SYSCALL_PARM_5 SYSCALL_PARM_4, long arg5
109#define SYSCALL_PARM_6 SYSCALL_PARM_5, long arg6
110
111#define SYSCALL_REGS_0
112#define SYSCALL_REGS_1 \
113 register long r2 asm("2") = arg1
114#define SYSCALL_REGS_2 \
115 SYSCALL_REGS_1; \
116 register long r3 asm("3") = arg2
117#define SYSCALL_REGS_3 \
118 SYSCALL_REGS_2; \
119 register long r4 asm("4") = arg3
120#define SYSCALL_REGS_4 \
121 SYSCALL_REGS_3; \
122 register long r5 asm("5") = arg4
123#define SYSCALL_REGS_5 \
124 SYSCALL_REGS_4; \
125 register long r6 asm("6") = arg5
126#define SYSCALL_REGS_6 \
127 SYSCALL_REGS_5; \
128 register long r7 asm("7") = arg6
129
130#define GENERATE_SYSCALL_FUNC(nr) \
131static __always_inline \
132long syscall##nr(unsigned long syscall SYSCALL_PARM_##nr) \
133{ \
134 register unsigned long r1 asm ("1") = syscall; \
135 register long rc asm ("2"); \
136 SYSCALL_REGS_##nr; \
137 \
138 asm volatile ( \
139 " svc 0\n" \
140 : "=d" (rc) \
141 : "d" (r1) SYSCALL_FMT_##nr \
142 : "memory"); \
143 return rc; \
144}
145
146GENERATE_SYSCALL_FUNC(0)
147GENERATE_SYSCALL_FUNC(1)
148GENERATE_SYSCALL_FUNC(2)
149GENERATE_SYSCALL_FUNC(3)
150GENERATE_SYSCALL_FUNC(4)
151GENERATE_SYSCALL_FUNC(5)
152GENERATE_SYSCALL_FUNC(6)
153
154#endif /* _ASM_SYSCALL_H */
1/*
2 * Access to user system call parameters and results
3 *
4 * Copyright IBM Corp. 2008
5 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License (version 2 only)
9 * as published by the Free Software Foundation.
10 */
11
12#ifndef _ASM_SYSCALL_H
13#define _ASM_SYSCALL_H 1
14
15#include <linux/sched.h>
16#include <asm/ptrace.h>
17
18/*
19 * The syscall table always contains 32 bit pointers since we know that the
20 * address of the function to be called is (way) below 4GB. So the "int"
21 * type here is what we want [need] for both 32 bit and 64 bit systems.
22 */
23extern const unsigned int sys_call_table[];
24
25static inline long syscall_get_nr(struct task_struct *task,
26 struct pt_regs *regs)
27{
28 return regs->svcnr ? regs->svcnr : -1;
29}
30
31static inline void syscall_rollback(struct task_struct *task,
32 struct pt_regs *regs)
33{
34 regs->gprs[2] = regs->orig_gpr2;
35}
36
37static inline long syscall_get_error(struct task_struct *task,
38 struct pt_regs *regs)
39{
40 return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0;
41}
42
43static inline long syscall_get_return_value(struct task_struct *task,
44 struct pt_regs *regs)
45{
46 return regs->gprs[2];
47}
48
49static inline void syscall_set_return_value(struct task_struct *task,
50 struct pt_regs *regs,
51 int error, long val)
52{
53 regs->gprs[2] = error ? -error : val;
54}
55
56static inline void syscall_get_arguments(struct task_struct *task,
57 struct pt_regs *regs,
58 unsigned int i, unsigned int n,
59 unsigned long *args)
60{
61 unsigned long mask = -1UL;
62
63 BUG_ON(i + n > 6);
64#ifdef CONFIG_COMPAT
65 if (test_tsk_thread_flag(task, TIF_31BIT))
66 mask = 0xffffffff;
67#endif
68 while (n-- > 0)
69 if (i + n > 0)
70 args[n] = regs->gprs[2 + i + n] & mask;
71 if (i == 0)
72 args[0] = regs->orig_gpr2 & mask;
73}
74
75static inline void syscall_set_arguments(struct task_struct *task,
76 struct pt_regs *regs,
77 unsigned int i, unsigned int n,
78 const unsigned long *args)
79{
80 BUG_ON(i + n > 6);
81 while (n-- > 0)
82 if (i + n > 0)
83 regs->gprs[2 + i + n] = args[n];
84 if (i == 0)
85 regs->orig_gpr2 = args[0];
86}
87
88#endif /* _ASM_SYSCALL_H */