Commit | Line | Data |
---|---|---|
19e2e172 | 1 | /* |
c0ff3c53 RB |
2 | * Access to user system call parameters and results |
3 | * | |
19e2e172 RB |
4 | * This file is subject to the terms and conditions of the GNU General Public |
5 | * License. See the file "COPYING" in the main directory of this archive | |
6 | * for more details. | |
7 | * | |
c0ff3c53 RB |
8 | * See asm-generic/syscall.h for descriptions of what we must do here. |
9 | * | |
19e2e172 RB |
10 | * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org> |
11 | */ | |
12 | ||
13 | #ifndef __ASM_MIPS_SYSCALL_H | |
14 | #define __ASM_MIPS_SYSCALL_H | |
15 | ||
f5179287 | 16 | #include <linux/compiler.h> |
579ec9e1 | 17 | #include <uapi/linux/audit.h> |
bec9b2b2 | 18 | #include <linux/elf-em.h> |
c0ff3c53 RB |
19 | #include <linux/kernel.h> |
20 | #include <linux/sched.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <asm/ptrace.h> | |
4c21b8fd MC |
23 | #include <asm/unistd.h> |
24 | ||
25 | #ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */ | |
26 | #define __NR_syscall 4000 | |
27 | #endif | |
c0ff3c53 | 28 | |
de8cd0dc JH |
29 | static inline bool mips_syscall_is_indirect(struct task_struct *task, |
30 | struct pt_regs *regs) | |
31 | { | |
32 | /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */ | |
33 | return (IS_ENABLED(CONFIG_32BIT) || | |
34 | test_tsk_thread_flag(task, TIF_32BIT_REGS)) && | |
35 | (regs->regs[2] == __NR_syscall); | |
36 | } | |
37 | ||
c0ff3c53 RB |
38 | static inline long syscall_get_nr(struct task_struct *task, |
39 | struct pt_regs *regs) | |
40 | { | |
c2d9f177 | 41 | return current_thread_info()->syscall; |
c0ff3c53 RB |
42 | } |
43 | ||
de8cd0dc JH |
44 | static inline void mips_syscall_update_nr(struct task_struct *task, |
45 | struct pt_regs *regs) | |
46 | { | |
47 | /* | |
48 | * v0 is the system call number, except for O32 ABI syscall(), where it | |
49 | * ends up in a0. | |
50 | */ | |
51 | if (mips_syscall_is_indirect(task, regs)) | |
52 | task_thread_info(task)->syscall = regs->regs[4]; | |
53 | else | |
54 | task_thread_info(task)->syscall = regs->regs[2]; | |
55 | } | |
56 | ||
c0ff3c53 RB |
57 | static inline unsigned long mips_get_syscall_arg(unsigned long *arg, |
58 | struct task_struct *task, struct pt_regs *regs, unsigned int n) | |
59 | { | |
63238f2c | 60 | unsigned long usp __maybe_unused = regs->regs[29]; |
c0ff3c53 RB |
61 | |
62 | switch (n) { | |
63 | case 0: case 1: case 2: case 3: | |
64 | *arg = regs->regs[4 + n]; | |
65 | ||
66 | return 0; | |
67 | ||
68 | #ifdef CONFIG_32BIT | |
69 | case 4: case 5: case 6: case 7: | |
86ca57b5 | 70 | return get_user(*arg, (int *)usp + n); |
c0ff3c53 RB |
71 | #endif |
72 | ||
73 | #ifdef CONFIG_64BIT | |
74 | case 4: case 5: case 6: case 7: | |
75 | #ifdef CONFIG_MIPS32_O32 | |
c50cbd85 | 76 | if (test_tsk_thread_flag(task, TIF_32BIT_REGS)) |
86ca57b5 | 77 | return get_user(*arg, (int *)usp + n); |
c0ff3c53 RB |
78 | else |
79 | #endif | |
80 | *arg = regs->regs[4 + n]; | |
81 | ||
82 | return 0; | |
83 | #endif | |
84 | ||
85 | default: | |
86 | BUG(); | |
87 | } | |
f5179287 RB |
88 | |
89 | unreachable(); | |
c0ff3c53 RB |
90 | } |
91 | ||
1d7bf993 RB |
92 | static inline long syscall_get_return_value(struct task_struct *task, |
93 | struct pt_regs *regs) | |
94 | { | |
95 | return regs->regs[2]; | |
96 | } | |
97 | ||
22feadbe MC |
98 | static inline void syscall_rollback(struct task_struct *task, |
99 | struct pt_regs *regs) | |
100 | { | |
101 | /* Do nothing */ | |
102 | } | |
103 | ||
1d7bf993 RB |
104 | static inline void syscall_set_return_value(struct task_struct *task, |
105 | struct pt_regs *regs, | |
106 | int error, long val) | |
107 | { | |
108 | if (error) { | |
109 | regs->regs[2] = -error; | |
becddba9 | 110 | regs->regs[7] = 1; |
1d7bf993 RB |
111 | } else { |
112 | regs->regs[2] = val; | |
113 | regs->regs[7] = 0; | |
114 | } | |
115 | } | |
116 | ||
c0ff3c53 RB |
117 | static inline void syscall_get_arguments(struct task_struct *task, |
118 | struct pt_regs *regs, | |
c0ff3c53 RB |
119 | unsigned long *args) |
120 | { | |
b35f549d SRRH |
121 | unsigned int i = 0; |
122 | unsigned int n = 6; | |
c0ff3c53 | 123 | int ret; |
de8cd0dc JH |
124 | |
125 | /* O32 ABI syscall() */ | |
126 | if (mips_syscall_is_indirect(task, regs)) | |
4c21b8fd | 127 | i++; |
c0ff3c53 RB |
128 | |
129 | while (n--) | |
a8031d2c | 130 | ret |= mips_get_syscall_arg(args++, task, regs, i++); |
c0ff3c53 RB |
131 | |
132 | /* | |
133 | * No way to communicate an error because this is a void function. | |
134 | */ | |
135 | #if 0 | |
136 | return ret; | |
137 | #endif | |
138 | } | |
139 | ||
19e2e172 RB |
140 | extern const unsigned long sys_call_table[]; |
141 | extern const unsigned long sys32_call_table[]; | |
142 | extern const unsigned long sysn32_call_table[]; | |
143 | ||
5e937a9a | 144 | static inline int syscall_get_arch(void) |
bec9b2b2 | 145 | { |
ce5d1128 | 146 | int arch = AUDIT_ARCH_MIPS; |
bec9b2b2 | 147 | #ifdef CONFIG_64BIT |
40381529 | 148 | if (!test_thread_flag(TIF_32BIT_REGS)) { |
6e345746 | 149 | arch |= __AUDIT_ARCH_64BIT; |
40381529 MC |
150 | /* N32 sets only TIF_32BIT_ADDR */ |
151 | if (test_thread_flag(TIF_32BIT_ADDR)) | |
152 | arch |= __AUDIT_ARCH_CONVENTION_MIPS64_N32; | |
153 | } | |
bec9b2b2 RB |
154 | #endif |
155 | #if defined(__LITTLE_ENDIAN) | |
156 | arch |= __AUDIT_ARCH_LE; | |
157 | #endif | |
158 | return arch; | |
159 | } | |
160 | ||
19e2e172 | 161 | #endif /* __ASM_MIPS_SYSCALL_H */ |