1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
; $Id: MMRamRCA.asm $
;; @file
; MMRamGCA - Guest Context Ram access Assembly Routines.
;
;
; Copyright (C) 2006-2007 Oracle Corporation
;
; This file is part of VirtualBox Open Source Edition (OSE), as
; available from http://www.virtualbox.org. This file is free software;
; you can redistribute it and/or modify it under the terms of the GNU
; General Public License (GPL) as published by the Free Software
; Foundation, in version 2 as it comes in the "COPYING" file of the
; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
;
;*******************************************************************************
;* Header Files *
;*******************************************************************************
%include "VBox/asmdefs.mac"
%include "VBox/err.mac"
%include "iprt/err.mac"
%include "iprt/x86.mac"
BEGINCODE
;;
; Read data in guest context, CDECL calling conv.
; VMMRCDECL(int) MMGCRamRead(void *pDst, void *pSrc, size_t cb);
; MMRamGC page fault handler must be installed prior this call for safe operation.
;
; @returns eax=0 if data read, other code - invalid access, #PF was generated.
; @param [esp + 04h] Param 1 - Pointer where to store result data (pDst).
; @param [esp + 08h] Param 2 - Pointer of data to read (pSrc).
; @param [esp + 0ch] Param 3 - Size of data to read, only 1/2/4/8 is valid.
; @uses eax, ecx, edx
;
; @remark Data is saved to destination (Param 1) even if read error occurred!
;
align 16
BEGINPROC MMGCRamReadNoTrapHandler
mov eax, [esp + 0ch] ; eax = size of data to read
cmp eax, byte 8 ; yes, it's slow, validate input
ja ramread_InvalidSize
mov edx, [esp + 04h] ; edx = result address
mov ecx, [esp + 08h] ; ecx = data address
jmp [ramread_table + eax*4]
ramread_byte:
xor eax, eax ; rc = VINF_SUCCESS by default
mov cl, [ecx] ; read data
mov [edx], cl ; save data
ret
ramread_word:
xor eax, eax ; rc = VINF_SUCCESS by default
mov cx, [ecx] ; read data
mov [edx], cx ; save data
ret
ramread_dword:
xor eax, eax ; rc = VINF_SUCCESS by default
mov ecx, [ecx] ; read data
mov [edx], ecx ; save data
ret
ramread_qword:
mov eax, [ecx] ; read data
mov [edx], eax ; save data
mov eax, [ecx+4] ; read data
mov [edx+4], eax ; save data
xor eax, eax ; rc = VINF_SUCCESS by default
ret
; Read error - we will be here after our page fault handler.
GLOBALNAME MMGCRamRead_Error
mov eax, VERR_ACCESS_DENIED
ret
; Invalid data size
ramread_InvalidSize:
mov eax, VERR_INVALID_PARAMETER
ret
; Jump table
ramread_table:
DD ramread_InvalidSize
DD ramread_byte
DD ramread_word
DD ramread_InvalidSize
DD ramread_dword
DD ramread_InvalidSize
DD ramread_InvalidSize
DD ramread_InvalidSize
DD ramread_qword
ENDPROC MMGCRamReadNoTrapHandler
;;
; Write data in guest context, CDECL calling conv.
; VMMRCDECL(int) MMGCRamWrite(void *pDst, void *pSrc, size_t cb);
;
; @returns eax=0 if data written, other code - invalid access, #PF was generated.
; @param [esp + 04h] Param 1 - Pointer where to write data (pDst).
; @param [esp + 08h] Param 2 - Pointer of data to write (pSrc).
; @param [esp + 0ch] Param 3 - Size of data to write, only 1/2/4 is valid.
; @uses eax, ecx, edx
;
align 16
BEGINPROC MMGCRamWriteNoTrapHandler
mov eax, [esp + 0ch] ; eax = size of data to write
cmp eax, byte 4 ; yes, it's slow, validate input
ja ramwrite_InvalidSize
mov edx, [esp + 04h] ; edx = write address
mov ecx, [esp + 08h] ; ecx = data address
jmp [ramwrite_table + eax*4]
ramwrite_byte:
xor eax, eax ; rc = VINF_SUCCESS by default
mov cl, [ecx] ; read data
mov [edx], cl ; write data
ret
ramwrite_word:
xor eax, eax ; rc = VINF_SUCCESS by default
mov cx, [ecx] ; read data
mov [edx], cx ; write data
ret
ramwrite_dword:
xor eax, eax ; rc = VINF_SUCCESS by default
mov ecx, [ecx] ; read data
mov [edx], ecx ; write data
ret
; Write error - we will be here after our page fault handler.
GLOBALNAME MMGCRamWrite_Error
mov eax, VERR_ACCESS_DENIED
ret
; Invalid data size
ramwrite_InvalidSize:
mov eax, VERR_INVALID_PARAMETER
ret
; Jump table
ramwrite_table:
DD ramwrite_InvalidSize
DD ramwrite_byte
DD ramwrite_word
DD ramwrite_InvalidSize
DD ramwrite_dword
ENDPROC MMGCRamWriteNoTrapHandler
|