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8
9#include <linux/linkage.h>
10#include <asm/page_types.h>
11#include <asm/kexec.h>
12#include <asm/processor-flags.h>
13
14
15
16
17
18#define PTR(x) (x << 2)
19
20
21
22
23
24
25#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
26
27
28#define ESP DATA(0x0)
29#define CR0 DATA(0x4)
30#define CR3 DATA(0x8)
31#define CR4 DATA(0xc)
32
33
34#define CP_VA_CONTROL_PAGE DATA(0x10)
35#define CP_PA_PGD DATA(0x14)
36#define CP_PA_SWAP_PAGE DATA(0x18)
37#define CP_PA_BACKUP_PAGES_MAP DATA(0x1c)
38
39 .text
40 .globl relocate_kernel
41relocate_kernel:
42
43
44 pushl %ebx
45 pushl %esi
46 pushl %edi
47 pushl %ebp
48 pushf
49
50 movl 20+8(%esp), %ebp
51 movl PTR(VA_CONTROL_PAGE)(%ebp), %edi
52 movl %esp, ESP(%edi)
53 movl %cr0, %eax
54 movl %eax, CR0(%edi)
55 movl %cr3, %eax
56 movl %eax, CR3(%edi)
57 movl %cr4, %eax
58 movl %eax, CR4(%edi)
59
60
61 movl 20+4(%esp), %ebx
62 movl 20+8(%esp), %ebp
63 movl 20+12(%esp), %edx
64 movl 20+16(%esp), %ecx
65 movl 20+20(%esp), %esi
66
67
68 pushl $0
69 popfl
70
71
72 movl PTR(VA_CONTROL_PAGE)(%ebp), %edi
73 movl %edi, CP_VA_CONTROL_PAGE(%edi)
74 movl PTR(PA_PGD)(%ebp), %eax
75 movl %eax, CP_PA_PGD(%edi)
76 movl PTR(PA_SWAP_PAGE)(%ebp), %eax
77 movl %eax, CP_PA_SWAP_PAGE(%edi)
78 movl %ebx, CP_PA_BACKUP_PAGES_MAP(%edi)
79
80
81
82
83
84 movl PTR(PA_CONTROL_PAGE)(%ebp), %edi
85
86
87 movl PTR(PA_PGD)(%ebp), %eax
88 movl %eax, %cr3
89
90
91 lea PAGE_SIZE(%edi), %esp
92
93
94 movl %edi, %eax
95 addl $(identity_mapped - relocate_kernel), %eax
96 pushl %eax
97 ret
98
99identity_mapped:
100
101 pushl $0
102
103 pushl %edx
104
105
106
107
108
109
110
111
112
113
114 movl %cr0, %eax
115 andl $~(X86_CR0_PG | X86_CR0_AM | X86_CR0_WP | X86_CR0_TS | X86_CR0_EM), %eax
116 orl $(X86_CR0_PE), %eax
117 movl %eax, %cr0
118
119
120 testl %ecx, %ecx
121 jz 1f
122
123
124
125
126 xorl %eax, %eax
127 movl %eax, %cr4
128
129 jmp 1f
1301:
131
132
133 xorl %eax, %eax
134 movl %eax, %cr3
135
136 movl CP_PA_SWAP_PAGE(%edi), %eax
137 pushl %eax
138 pushl %ebx
139 call swap_pages
140 addl $8, %esp
141
142
143
144
145
146
147 xorl %eax, %eax
148 movl %eax, %cr3
149
150
151
152
153
154
155 testl %esi, %esi
156 jnz 1f
157 xorl %edi, %edi
158 xorl %eax, %eax
159 xorl %ebx, %ebx
160 xorl %ecx, %ecx
161 xorl %edx, %edx
162 xorl %esi, %esi
163 xorl %ebp, %ebp
164 ret
1651:
166 popl %edx
167 movl CP_PA_SWAP_PAGE(%edi), %esp
168 addl $PAGE_SIZE, %esp
1692:
170 call *%edx
171
172
173 movl 0(%esp), %ebp
174 call 1f
1751:
176 popl %ebx
177 subl $(1b - relocate_kernel), %ebx
178 movl CP_VA_CONTROL_PAGE(%ebx), %edi
179 lea PAGE_SIZE(%ebx), %esp
180 movl CP_PA_SWAP_PAGE(%ebx), %eax
181 movl CP_PA_BACKUP_PAGES_MAP(%ebx), %edx
182 pushl %eax
183 pushl %edx
184 call swap_pages
185 addl $8, %esp
186 movl CP_PA_PGD(%ebx), %eax
187 movl %eax, %cr3
188 movl %cr0, %eax
189 orl $X86_CR0_PG, %eax
190 movl %eax, %cr0
191 lea PAGE_SIZE(%edi), %esp
192 movl %edi, %eax
193 addl $(virtual_mapped - relocate_kernel), %eax
194 pushl %eax
195 ret
196
197virtual_mapped:
198 movl CR4(%edi), %eax
199 movl %eax, %cr4
200 movl CR3(%edi), %eax
201 movl %eax, %cr3
202 movl CR0(%edi), %eax
203 movl %eax, %cr0
204 movl ESP(%edi), %esp
205 movl %ebp, %eax
206
207 popf
208 popl %ebp
209 popl %edi
210 popl %esi
211 popl %ebx
212 ret
213
214
215swap_pages:
216 movl 8(%esp), %edx
217 movl 4(%esp), %ecx
218 pushl %ebp
219 pushl %ebx
220 pushl %edi
221 pushl %esi
222 movl %ecx, %ebx
223 jmp 1f
224
2250:
226 movl (%ebx), %ecx
227 addl $4, %ebx
2281:
229 testb $0x1, %cl
230 jz 2f
231 movl %ecx, %edi
232 andl $0xfffff000, %edi
233 jmp 0b
2342:
235 testb $0x2, %cl
236 jz 2f
237 movl %ecx, %ebx
238 andl $0xfffff000, %ebx
239 jmp 0b
2402:
241 testb $0x4, %cl
242 jz 2f
243 jmp 3f
2442:
245 testb $0x8, %cl
246 jz 0b
247 movl %ecx, %esi
248 andl $0xfffff000, %esi
249
250 movl %edi, %eax
251 movl %esi, %ebp
252
253 movl %edx, %edi
254 movl $1024, %ecx
255 rep ; movsl
256
257 movl %ebp, %edi
258 movl %eax, %esi
259 movl $1024, %ecx
260 rep ; movsl
261
262 movl %eax, %edi
263 movl %edx, %esi
264 movl $1024, %ecx
265 rep ; movsl
266
267 lea PAGE_SIZE(%ebp), %esi
268 jmp 0b
2693:
270 popl %esi
271 popl %edi
272 popl %ebx
273 popl %ebp
274 ret
275
276 .globl kexec_control_code_size
277.set kexec_control_code_size, . - relocate_kernel
278