1/*
2 * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
3 * Licensed under the GPL
4 */
5
6#ifndef __SYSDEP_STUB_H
7#define __SYSDEP_STUB_H
8
9#include <sysdep/ptrace_user.h>
10#include <generated/asm-offsets.h>
11#include <linux/stddef.h>
12
13#define STUB_MMAP_NR __NR_mmap
14#define MMAP_OFFSET(o) (o)
15
16#define __syscall_clobber "r11","rcx","memory"
17#define __syscall "syscall"
18
19static inline long stub_syscall0(long syscall)
20{
21	long ret;
22
23	__asm__ volatile (__syscall
24		: "=a" (ret)
25		: "0" (syscall) : __syscall_clobber );
26
27	return ret;
28}
29
30static inline long stub_syscall2(long syscall, long arg1, long arg2)
31{
32	long ret;
33
34	__asm__ volatile (__syscall
35		: "=a" (ret)
36		: "0" (syscall), "D" (arg1), "S" (arg2) : __syscall_clobber );
37
38	return ret;
39}
40
41static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
42{
43	long ret;
44
45	__asm__ volatile (__syscall
46		: "=a" (ret)
47		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3)
48		: __syscall_clobber );
49
50	return ret;
51}
52
53static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
54				 long arg4)
55{
56	long ret;
57
58	__asm__ volatile ("movq %5,%%r10 ; " __syscall
59		: "=a" (ret)
60		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
61		  "g" (arg4)
62		: __syscall_clobber, "r10" );
63
64	return ret;
65}
66
67static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
68				 long arg4, long arg5)
69{
70	long ret;
71
72	__asm__ volatile ("movq %5,%%r10 ; movq %6,%%r8 ; " __syscall
73		: "=a" (ret)
74		: "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
75		  "g" (arg4), "g" (arg5)
76		: __syscall_clobber, "r10", "r8" );
77
78	return ret;
79}
80
81static inline void trap_myself(void)
82{
83	__asm("int3");
84}
85
86static inline void remap_stack_and_trap(void)
87{
88	__asm__ volatile (
89		"movq %0,%%rax ;"
90		"movq %%rsp,%%rdi ;"
91		"andq %1,%%rdi ;"
92		"movq %2,%%r10 ;"
93		"movq %%rdi,%%r8 ; addq %3,%%r8 ; movq (%%r8),%%r8 ;"
94		"movq %%rdi,%%r9 ; addq %4,%%r9 ; movq (%%r9),%%r9 ;"
95		__syscall ";"
96		"movq %%rsp,%%rdi ; andq %1,%%rdi ;"
97		"addq %5,%%rdi ; movq %%rax, (%%rdi) ;"
98		"int3"
99		: :
100		"g" (STUB_MMAP_NR),
101		"g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
102		"g" (MAP_FIXED | MAP_SHARED),
103		"g" (UML_STUB_FIELD_FD),
104		"g" (UML_STUB_FIELD_OFFSET),
105		"g" (UML_STUB_FIELD_CHILD_ERR),
106		"S" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
107		"d" (PROT_READ | PROT_WRITE)
108		:
109		__syscall_clobber, "r10", "r8", "r9");
110}
111
112static __always_inline void *get_stub_data(void)
113{
114	unsigned long ret;
115
116	asm volatile (
117		"movq %%rsp,%0 ;"
118		"andq %1,%0"
119		: "=a" (ret)
120		: "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
121
122	return (void *)ret;
123}
124#endif
125