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