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
|
#include <os.h>
#include <arch_limits.h>
#include <xen/arch-x86_64.h>
/* For simplicity, we keep all of this into just one data page */
.data
.globl _boot_page
_boot_page:
.align __PAGE_SIZE
/*
* The following data is initialized from C code
*/
/* Pte of this page */
.globl _boot_page_entry
_boot_page_entry:
.quad 0
/* mmuext_op structure */
/* Set new page directory */
_boot_mmuext:
/* Op # */
.long MMUEXT_NEW_BASEPTR
.long 0 /* pad */
/* MFN of target page table directory */
.globl _boot_pdmfn
_boot_pdmfn:
.quad 0
/* Unused */
.quad 0
/* Unpin old page directory */
/* Op # */
.long MMUEXT_UNPIN_TABLE
.long 0 /* pad */
/* MFN of old page table directory */
.globl _boot_oldpdmfn
_boot_oldpdmfn:
.quad 0
/* Unused */
.quad 0
/* Target stack address, also target virtual address of this page */
.globl _boot_stack
_boot_stack:
.quad 0
.globl _boot_target
_boot_target:
.quad 0
/* Target start info */
.globl _boot_start_info
_boot_start_info:
.quad 0
/* Target start address */
.globl _boot_start
_boot_start:
.quad 0
/*
* Boot target OS, does not return
*/
.globl _boot
_boot:
/* Project ourselves at the target place. */
movq _boot_target, %rdi
movq _boot_page_entry, %rsi
movq $2, %rdx /* UVMF_INVLPG */
movq $__HYPERVISOR_update_va_mapping, %rax
syscall
testq %rax, %rax
jz 0f
ud2
0:
/* Go there. */
movq $(0f - _boot_page), %rax
movq _boot_target, %rbx
addq %rbx, %rax
jmpq *%rax
0:
/* Load target page table and unpin old page table. */
/* We shouldn't have any problem since in the new page table our page is
mapped at the same place. */
leaq _boot_mmuext(%rip), %rdi
movq $2, %rsi
xorq %rdx, %rdx
movq $0x7FF0, %r10 /* DOMID_SELF */
movq $__HYPERVISOR_mmuext_op, %rax
syscall
testq %rax, %rax
jns 0f
ud2
0:
/* Initialize registers. */
movq _boot_stack(%rip), %rsp
movq _boot_start_info(%rip), %rsi
/* Jump! */
jmpq *_boot_start(%rip)
|