UbixOS V2 2.0

page_fault.S
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1 /*-
2 * Copyright (c) 2002-2018 The UbixOS Project.
3 * All rights reserved.
4 *
5 * This was developed by Christopher W. Olsen for the UbixOS Project.
6 *
7 * Redistribution and use in source and binary forms, with or without modification, are permitted
8 * provided that the following conditions are met:
9 *
10 * 1) Redistributions of source code must retain the above copyright notice, this list of
11 * conditions, the following disclaimer and the list of authors.
12 * 2) Redistributions in binary form must reproduce the above copyright notice, this list of
13 * conditions, the following disclaimer and the list of authors in the documentation and/or
14 * other materials provided with the distribution.
15 * 3) Neither the name of the UbixOS Project nor the names of its contributors may be used to
16 * endorse or promote products derived from this software without specific prior written
17 * permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
22 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
24 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /*
30 Page fault wrapper this will aquire some values we need for later use
31 */
32
33 .globl _vmm_pageFault2
34 .text
35 .code32
36 _vmm_pageFault2:
37 xchgl %eax,(%esp) /* Save EAX */
38 movl 4(%esp),%eax /* Move EIP into EAX to use later */
39 pushl %ebx /* Save EBX */
40 movl 20(%esp),%ebx /* Save ESP for ring 3 to use later */
41 pushl %ecx /* Save ECX,EDX */
42 pushl %edx
43 push %ebx /* Push ESP */
44 push %eax /* Push EIP */
45 movl %cr2,%eax /* Push the faulted address */
46 pushl %eax
47 sti /* Turn interrupts back on we are now entrant safe */
48 call vmm_pageFault /* Call our page fault handler */
49 addl $0xC,%esp /* Adjust the stack to compensate for pushed values */
50 popl %edx /* Restore EAX,EBX,ECX,EDX */
51 popl %ecx
52 popl %ebx
53 popl %eax
54 iret /* Return from the interrupt */
55
56 .globl _vmm_pageFault
57 .text
58 .code32
59
60 _B4:
61 _B3:
62 nop
63
64 _ast:
65
66 _astRet:
67
68 _vmm_pageFault:
69 pushl $0xC
70 pushal
71 push %ds
72 push %es
73 push %fs
74 push %gs
75 mov $0x10,%eax
76 mov %eax,%ds
77 mov %eax,%es
78 mov %eax,%fs
79 cld
80 push %esp
81 call trap
82 notyet:
83 pushl %eax
84 sti
85 call vmm_pageFault
86 /* call syscall */
87 add $0x4,%esp
88 cmpb $0x13,0x38(%esp)
89 je _B4
90 testl $0x2000,0x3c(%esp) /* Test If VM */
91 jz _notVM
92 jmp _isVM
93 _notVM:
94 testb $0x3,0x38(%esp) /* See If We're In User CS (GDT Entry 5) */
95 jz _popFS
96 cli
97 mov %fs:0x0,%eax
98 testl $0x10800,0x80(%eax) /* Document This */
99 je _popFS
100 sti
101 push %esp
102 call _ast
103 add $0x4,%esp
104 jmp _astRet
105 _isVM:
106 hlt
107
108 _popFS:
109 pop %gs
110 pop %fs
111 pop %es
112 pop %ds
113 popa
114 add $0x8,%esp
115 iret
116
117 /***
118 END
119 ***/