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 <asm/ptrace.h>
10 #include <generated/asm-offsets.h>
11
12 #define STUB_MMAP_NR __NR_mmap2
13 #define MMAP_OFFSET(o) ((o) >> UM_KERN_PAGE_SHIFT)
14
stub_syscall0(long syscall)15 static inline long stub_syscall0(long syscall)
16 {
17 long ret;
18
19 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall));
20
21 return ret;
22 }
23
stub_syscall1(long syscall,long arg1)24 static inline long stub_syscall1(long syscall, long arg1)
25 {
26 long ret;
27
28 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1));
29
30 return ret;
31 }
32
stub_syscall2(long syscall,long arg1,long arg2)33 static inline long stub_syscall2(long syscall, long arg1, long arg2)
34 {
35 long ret;
36
37 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
38 "c" (arg2));
39
40 return ret;
41 }
42
stub_syscall3(long syscall,long arg1,long arg2,long arg3)43 static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
44 {
45 long ret;
46
47 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
48 "c" (arg2), "d" (arg3));
49
50 return ret;
51 }
52
stub_syscall4(long syscall,long arg1,long arg2,long arg3,long arg4)53 static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
54 long arg4)
55 {
56 long ret;
57
58 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
59 "c" (arg2), "d" (arg3), "S" (arg4));
60
61 return ret;
62 }
63
stub_syscall5(long syscall,long arg1,long arg2,long arg3,long arg4,long arg5)64 static inline long stub_syscall5(long syscall, long arg1, long arg2, long arg3,
65 long arg4, long arg5)
66 {
67 long ret;
68
69 __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
70 "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5));
71
72 return ret;
73 }
74
trap_myself(void)75 static inline void trap_myself(void)
76 {
77 __asm("int3");
78 }
79
remap_stack_and_trap(void)80 static inline void remap_stack_and_trap(void)
81 {
82 __asm__ volatile (
83 "movl %%esp,%%ebx ;"
84 "andl %0,%%ebx ;"
85 "movl %1,%%eax ;"
86 "movl %%ebx,%%edi ; addl %2,%%edi ; movl (%%edi),%%edi ;"
87 "movl %%ebx,%%ebp ; addl %3,%%ebp ; movl (%%ebp),%%ebp ;"
88 "int $0x80 ;"
89 "addl %4,%%ebx ; movl %%eax, (%%ebx) ;"
90 "int $3"
91 : :
92 "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)),
93 "g" (STUB_MMAP_NR),
94 "g" (UML_STUB_FIELD_FD),
95 "g" (UML_STUB_FIELD_OFFSET),
96 "g" (UML_STUB_FIELD_CHILD_ERR),
97 "c" (STUB_DATA_PAGES * UM_KERN_PAGE_SIZE),
98 "d" (PROT_READ | PROT_WRITE),
99 "S" (MAP_FIXED | MAP_SHARED)
100 :
101 "memory");
102 }
103
get_stub_data(void)104 static __always_inline void *get_stub_data(void)
105 {
106 unsigned long ret;
107
108 asm volatile (
109 "movl %%esp,%0 ;"
110 "andl %1,%0"
111 : "=a" (ret)
112 : "g" (~(STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - 1)));
113
114 return (void *)ret;
115 }
116 #endif
117