Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * Copyright (C) 2012 ARM Ltd.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 */
16#ifndef __ASM_SYSCALL_H
17#define __ASM_SYSCALL_H
18
19#include <linux/err.h>
20
21
22static inline int syscall_get_nr(struct task_struct *task,
23 struct pt_regs *regs)
24{
25 return regs->syscallno;
26}
27
28static inline void syscall_rollback(struct task_struct *task,
29 struct pt_regs *regs)
30{
31 regs->regs[0] = regs->orig_x0;
32}
33
34
35static inline long syscall_get_error(struct task_struct *task,
36 struct pt_regs *regs)
37{
38 unsigned long error = regs->regs[0];
39 return IS_ERR_VALUE(error) ? error : 0;
40}
41
42static inline long syscall_get_return_value(struct task_struct *task,
43 struct pt_regs *regs)
44{
45 return regs->regs[0];
46}
47
48static inline void syscall_set_return_value(struct task_struct *task,
49 struct pt_regs *regs,
50 int error, long val)
51{
52 regs->regs[0] = (long) error ? error : val;
53}
54
55#define SYSCALL_MAX_ARGS 6
56
57static inline void syscall_get_arguments(struct task_struct *task,
58 struct pt_regs *regs,
59 unsigned int i, unsigned int n,
60 unsigned long *args)
61{
62 if (i + n > SYSCALL_MAX_ARGS) {
63 unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i;
64 unsigned int n_bad = n + i - SYSCALL_MAX_ARGS;
65 pr_warning("%s called with max args %d, handling only %d\n",
66 __func__, i + n, SYSCALL_MAX_ARGS);
67 memset(args_bad, 0, n_bad * sizeof(args[0]));
68 }
69
70 if (i == 0) {
71 args[0] = regs->orig_x0;
72 args++;
73 i++;
74 n--;
75 }
76
77 memcpy(args, ®s->regs[i], n * sizeof(args[0]));
78}
79
80static inline void syscall_set_arguments(struct task_struct *task,
81 struct pt_regs *regs,
82 unsigned int i, unsigned int n,
83 const unsigned long *args)
84{
85 if (i + n > SYSCALL_MAX_ARGS) {
86 pr_warning("%s called with max args %d, handling only %d\n",
87 __func__, i + n, SYSCALL_MAX_ARGS);
88 n = SYSCALL_MAX_ARGS - i;
89 }
90
91 if (i == 0) {
92 regs->orig_x0 = args[0];
93 args++;
94 i++;
95 n--;
96 }
97
98 memcpy(®s->regs[i], args, n * sizeof(args[0]));
99}
100
101#endif /* __ASM_SYSCALL_H */