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
stub_syscall0(long syscall)19 static __always_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
stub_syscall2(long syscall,long arg1,long arg2)30 static __always_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
stub_syscall3(long syscall,long arg1,long arg2,long arg3)41 static __always_inline long stub_syscall3(long syscall, long arg1, long arg2,
42 long arg3)
43 {
44 long ret;
45
46 __asm__ volatile (__syscall
47 : "=a" (ret)
48 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3)
49 : __syscall_clobber );
50
51 return ret;
52 }
53
stub_syscall4(long syscall,long arg1,long arg2,long arg3,long arg4)54 static __always_inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
55 long arg4)
56 {
57 long ret;
58
59 __asm__ volatile ("movq %5,%%r10 ; " __syscall
60 : "=a" (ret)
61 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
62 "g" (arg4)
63 : __syscall_clobber, "r10" );
64
65 return ret;
66 }
67
stub_syscall5(long syscall,long arg1,long arg2,long arg3,long arg4,long arg5)68 static __always_inline long stub_syscall5(long syscall, long arg1, long arg2,
69 long arg3, long arg4, long arg5)
70 {
71 long ret;
72
73 __asm__ volatile ("movq %5,%%r10 ; movq %6,%%r8 ; " __syscall
74 : "=a" (ret)
75 : "0" (syscall), "D" (arg1), "S" (arg2), "d" (arg3),
76 "g" (arg4), "g" (arg5)
77 : __syscall_clobber, "r10", "r8" );
78
79 return ret;
80 }
81
trap_myself(void)82 static __always_inline void trap_myself(void)
83 {
84 __asm("int3");
85 }
86
remap_stack_and_trap(void)87 static __always_inline void remap_stack_and_trap(void)
88 {
89 __asm__ volatile (
90 "movq %0,%%rax ;"
91 "movq %%rsp,%%rdi ;"
92 "andq %1,%%rdi ;"
93 "movq %2,%%r10 ;"
94 "movq %%rdi,%%r8 ; addq %3,%%r8 ; movq (%%r8),%%r8 ;"
95 "movq %%rdi,%%r9 ; addq %4,%%r9 ; movq (%%r9),%%r9 ;"
96 __syscall ";"
97 "movq %%rsp,%%rdi ; andq %1,%%rdi ;"
98 "addq %5,%%rdi ; movq %%rax, (%%rdi) ;"
99 "int3"
100 : :
101 "g" (STUB_MMAP_NR),
102 "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
103 "g" (MAP_FIXED | MAP_SHARED),
104 "g" (UML_STUB_FIELD_FD),
105 "g" (UML_STUB_FIELD_OFFSET),
106 "g" (UML_STUB_FIELD_CHILD_ERR),
107 "S" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
108 "d" (PROT_READ | PROT_WRITE)
109 :
110 __syscall_clobber, "r10", "r8", "r9");
111 }
112
get_stub_data(void)113 static __always_inline void *get_stub_data(void)
114 {
115 unsigned long ret;
116
117 asm volatile (
118 "movq %%rsp,%0 ;"
119 "andq %1,%0"
120 : "=a" (ret)
121 : "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
122
123 return (void *)ret;
124 }
125 #endif
126