Linux kernel mirror (for testing)
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linux
1#ifndef __ASM_SH_SYSCALL_32_H
2#define __ASM_SH_SYSCALL_32_H
3
4#include <linux/kernel.h>
5#include <linux/sched.h>
6#include <linux/err.h>
7#include <asm/ptrace.h>
8
9/* The system call number is given by the user in R3 */
10static inline long syscall_get_nr(struct task_struct *task,
11 struct pt_regs *regs)
12{
13 return (regs->tra >= 0) ? regs->regs[3] : -1L;
14}
15
16static inline void syscall_rollback(struct task_struct *task,
17 struct pt_regs *regs)
18{
19 /*
20 * XXX: This needs some thought. On SH we don't
21 * save away the original r0 value anywhere.
22 */
23}
24
25static inline long syscall_get_error(struct task_struct *task,
26 struct pt_regs *regs)
27{
28 return IS_ERR_VALUE(regs->regs[0]) ? regs->regs[0] : 0;
29}
30
31static inline long syscall_get_return_value(struct task_struct *task,
32 struct pt_regs *regs)
33{
34 return regs->regs[0];
35}
36
37static inline void syscall_set_return_value(struct task_struct *task,
38 struct pt_regs *regs,
39 int error, long val)
40{
41 if (error)
42 regs->regs[0] = -error;
43 else
44 regs->regs[0] = val;
45}
46
47static inline void syscall_get_arguments(struct task_struct *task,
48 struct pt_regs *regs,
49 unsigned int i, unsigned int n,
50 unsigned long *args)
51{
52 /*
53 * Do this simply for now. If we need to start supporting
54 * fetching arguments from arbitrary indices, this will need some
55 * extra logic. Presently there are no in-tree users that depend
56 * on this behaviour.
57 */
58 BUG_ON(i);
59
60 /* Argument pattern is: R4, R5, R6, R7, R0, R1 */
61 switch (n) {
62 case 6: args[5] = regs->regs[1];
63 case 5: args[4] = regs->regs[0];
64 case 4: args[3] = regs->regs[7];
65 case 3: args[2] = regs->regs[6];
66 case 2: args[1] = regs->regs[5];
67 case 1: args[0] = regs->regs[4];
68 case 0:
69 break;
70 default:
71 BUG();
72 }
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 /* Same note as above applies */
81 BUG_ON(i);
82
83 switch (n) {
84 case 6: regs->regs[1] = args[5];
85 case 5: regs->regs[0] = args[4];
86 case 4: regs->regs[7] = args[3];
87 case 3: regs->regs[6] = args[2];
88 case 2: regs->regs[5] = args[1];
89 case 1: regs->regs[4] = args[0];
90 break;
91 default:
92 BUG();
93 }
94}
95
96#endif /* __ASM_SH_SYSCALL_32_H */