1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2011 NetApp, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/types.h>
30
31 #include <machine/specialreg.h>
32 #include <machine/segments.h>
33 #include <machine/vmm.h>
34
35 #include <errno.h>
36 #include <string.h>
37
38 #include "vmmapi.h"
39 #include "internal.h"
40
41 #define I386_TSS_SIZE 104
42
43 #define DESC_PRESENT 0x00000080
44 #define DESC_LONGMODE 0x00002000
45 #define DESC_DEF32 0x00004000
46 #define DESC_GRAN 0x00008000
47 #define DESC_UNUSABLE 0x00010000
48
49 #define GUEST_NULL_SEL 0
50 #define GUEST_CODE_SEL 1
51 #define GUEST_DATA_SEL 2
52 #define GUEST_TSS_SEL 3
53 #define GUEST_GDTR_LIMIT64 (3 * 8 - 1)
54
55 static struct segment_descriptor i386_gdt[] = {
56 {}, /* NULL */
57 { .sd_lolimit = 0xffff, .sd_type = SDT_MEMER, /* CODE */
58 .sd_p = 1, .sd_hilimit = 0xf, .sd_def32 = 1, .sd_gran = 1 },
59 { .sd_lolimit = 0xffff, .sd_type = SDT_MEMRW, /* DATA */
60 .sd_p = 1, .sd_hilimit = 0xf, .sd_def32 = 1, .sd_gran = 1 },
61 { .sd_lolimit = I386_TSS_SIZE - 1, /* TSS */
62 .sd_type = SDT_SYS386TSS, .sd_p = 1 }
63 };
64
65 /*
66 * Setup the 'vcpu' register set such that it will begin execution at
67 * 'eip' in flat mode.
68 */
69 int
vm_setup_freebsd_registers_i386(struct vcpu * vcpu,uint32_t eip,uint32_t gdtbase,uint32_t esp)70 vm_setup_freebsd_registers_i386(struct vcpu *vcpu, uint32_t eip,
71 uint32_t gdtbase, uint32_t esp)
72 {
73 uint64_t cr0, rflags, desc_base;
74 uint32_t desc_access, desc_limit, tssbase;
75 uint16_t gsel;
76 struct segment_descriptor *gdt;
77 int error, tmp;
78
79 /* A 32-bit guest requires unrestricted mode. */
80 error = vm_get_capability(vcpu, VM_CAP_UNRESTRICTED_GUEST, &tmp);
81 if (error)
82 goto done;
83 error = vm_set_capability(vcpu, VM_CAP_UNRESTRICTED_GUEST, 1);
84 if (error)
85 goto done;
86
87 cr0 = CR0_PE | CR0_NE;
88 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CR0, cr0)) != 0)
89 goto done;
90
91 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CR4, 0)) != 0)
92 goto done;
93
94 /*
95 * Forcing EFER to 0 causes bhyve to clear the "IA-32e guest
96 * mode" entry control.
97 */
98 if ((error = vm_set_register(vcpu, VM_REG_GUEST_EFER, 0)))
99 goto done;
100
101 gdt = vm_map_gpa(vcpu->ctx, gdtbase, 0x1000);
102 if (gdt == NULL)
103 return (EFAULT);
104 memcpy(gdt, i386_gdt, sizeof(i386_gdt));
105 desc_base = gdtbase;
106 desc_limit = sizeof(i386_gdt) - 1;
107 error = vm_set_desc(vcpu, VM_REG_GUEST_GDTR,
108 desc_base, desc_limit, 0);
109 if (error != 0)
110 goto done;
111
112 /* Place the TSS one page above the GDT. */
113 tssbase = gdtbase + 0x1000;
114 gdt[3].sd_lobase = tssbase;
115
116 rflags = 0x2;
117 error = vm_set_register(vcpu, VM_REG_GUEST_RFLAGS, rflags);
118 if (error)
119 goto done;
120
121 desc_base = 0;
122 desc_limit = 0xffffffff;
123 desc_access = DESC_GRAN | DESC_DEF32 | DESC_PRESENT | SDT_MEMERA;
124 error = vm_set_desc(vcpu, VM_REG_GUEST_CS,
125 desc_base, desc_limit, desc_access);
126
127 desc_access = DESC_GRAN | DESC_DEF32 | DESC_PRESENT | SDT_MEMRWA;
128 error = vm_set_desc(vcpu, VM_REG_GUEST_DS,
129 desc_base, desc_limit, desc_access);
130 if (error)
131 goto done;
132
133 error = vm_set_desc(vcpu, VM_REG_GUEST_ES,
134 desc_base, desc_limit, desc_access);
135 if (error)
136 goto done;
137
138 error = vm_set_desc(vcpu, VM_REG_GUEST_FS,
139 desc_base, desc_limit, desc_access);
140 if (error)
141 goto done;
142
143 error = vm_set_desc(vcpu, VM_REG_GUEST_GS,
144 desc_base, desc_limit, desc_access);
145 if (error)
146 goto done;
147
148 error = vm_set_desc(vcpu, VM_REG_GUEST_SS,
149 desc_base, desc_limit, desc_access);
150 if (error)
151 goto done;
152
153 desc_base = tssbase;
154 desc_limit = I386_TSS_SIZE - 1;
155 desc_access = DESC_PRESENT | SDT_SYS386BSY;
156 error = vm_set_desc(vcpu, VM_REG_GUEST_TR,
157 desc_base, desc_limit, desc_access);
158 if (error)
159 goto done;
160
161
162 error = vm_set_desc(vcpu, VM_REG_GUEST_LDTR, 0, 0,
163 DESC_UNUSABLE);
164 if (error)
165 goto done;
166
167 gsel = GSEL(GUEST_CODE_SEL, SEL_KPL);
168 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CS, gsel)) != 0)
169 goto done;
170
171 gsel = GSEL(GUEST_DATA_SEL, SEL_KPL);
172 if ((error = vm_set_register(vcpu, VM_REG_GUEST_DS, gsel)) != 0)
173 goto done;
174
175 if ((error = vm_set_register(vcpu, VM_REG_GUEST_ES, gsel)) != 0)
176 goto done;
177
178 if ((error = vm_set_register(vcpu, VM_REG_GUEST_FS, gsel)) != 0)
179 goto done;
180
181 if ((error = vm_set_register(vcpu, VM_REG_GUEST_GS, gsel)) != 0)
182 goto done;
183
184 if ((error = vm_set_register(vcpu, VM_REG_GUEST_SS, gsel)) != 0)
185 goto done;
186
187 gsel = GSEL(GUEST_TSS_SEL, SEL_KPL);
188 if ((error = vm_set_register(vcpu, VM_REG_GUEST_TR, gsel)) != 0)
189 goto done;
190
191 /* LDTR is pointing to the null selector */
192 if ((error = vm_set_register(vcpu, VM_REG_GUEST_LDTR, 0)) != 0)
193 goto done;
194
195 /* entry point */
196 if ((error = vm_set_register(vcpu, VM_REG_GUEST_RIP, eip)) != 0)
197 goto done;
198
199 if ((error = vm_set_register(vcpu, VM_REG_GUEST_RSP, esp)) != 0)
200 goto done;
201
202 error = 0;
203 done:
204 return (error);
205 }
206
207 void
vm_setup_freebsd_gdt(uint64_t * gdtr)208 vm_setup_freebsd_gdt(uint64_t *gdtr)
209 {
210 gdtr[GUEST_NULL_SEL] = 0;
211 gdtr[GUEST_CODE_SEL] = 0x0020980000000000;
212 gdtr[GUEST_DATA_SEL] = 0x0000900000000000;
213 }
214
215 /*
216 * Setup the 'vcpu' register set such that it will begin execution at
217 * 'rip' in long mode.
218 */
219 int
vm_setup_freebsd_registers(struct vcpu * vcpu,uint64_t rip,uint64_t cr3,uint64_t gdtbase,uint64_t rsp)220 vm_setup_freebsd_registers(struct vcpu *vcpu,
221 uint64_t rip, uint64_t cr3, uint64_t gdtbase,
222 uint64_t rsp)
223 {
224 int error;
225 uint64_t cr0, cr4, efer, rflags, desc_base;
226 uint32_t desc_access, desc_limit;
227 uint16_t gsel;
228
229 cr0 = CR0_PE | CR0_PG | CR0_NE;
230 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CR0, cr0)) != 0)
231 goto done;
232
233 cr4 = CR4_PAE;
234 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CR4, cr4)) != 0)
235 goto done;
236
237 efer = EFER_LME | EFER_LMA;
238 if ((error = vm_set_register(vcpu, VM_REG_GUEST_EFER, efer)))
239 goto done;
240
241 rflags = 0x2;
242 error = vm_set_register(vcpu, VM_REG_GUEST_RFLAGS, rflags);
243 if (error)
244 goto done;
245
246 desc_base = 0;
247 desc_limit = 0;
248 desc_access = 0x0000209B;
249 error = vm_set_desc(vcpu, VM_REG_GUEST_CS,
250 desc_base, desc_limit, desc_access);
251 if (error)
252 goto done;
253
254 desc_access = 0x00000093;
255 error = vm_set_desc(vcpu, VM_REG_GUEST_DS,
256 desc_base, desc_limit, desc_access);
257 if (error)
258 goto done;
259
260 error = vm_set_desc(vcpu, VM_REG_GUEST_ES,
261 desc_base, desc_limit, desc_access);
262 if (error)
263 goto done;
264
265 error = vm_set_desc(vcpu, VM_REG_GUEST_FS,
266 desc_base, desc_limit, desc_access);
267 if (error)
268 goto done;
269
270 error = vm_set_desc(vcpu, VM_REG_GUEST_GS,
271 desc_base, desc_limit, desc_access);
272 if (error)
273 goto done;
274
275 error = vm_set_desc(vcpu, VM_REG_GUEST_SS,
276 desc_base, desc_limit, desc_access);
277 if (error)
278 goto done;
279
280 /*
281 * XXX TR is pointing to null selector even though we set the
282 * TSS segment to be usable with a base address and limit of 0.
283 */
284 desc_access = 0x0000008b;
285 error = vm_set_desc(vcpu, VM_REG_GUEST_TR, 0, 0, desc_access);
286 if (error)
287 goto done;
288
289 error = vm_set_desc(vcpu, VM_REG_GUEST_LDTR, 0, 0,
290 DESC_UNUSABLE);
291 if (error)
292 goto done;
293
294 gsel = GSEL(GUEST_CODE_SEL, SEL_KPL);
295 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CS, gsel)) != 0)
296 goto done;
297
298 gsel = GSEL(GUEST_DATA_SEL, SEL_KPL);
299 if ((error = vm_set_register(vcpu, VM_REG_GUEST_DS, gsel)) != 0)
300 goto done;
301
302 if ((error = vm_set_register(vcpu, VM_REG_GUEST_ES, gsel)) != 0)
303 goto done;
304
305 if ((error = vm_set_register(vcpu, VM_REG_GUEST_FS, gsel)) != 0)
306 goto done;
307
308 if ((error = vm_set_register(vcpu, VM_REG_GUEST_GS, gsel)) != 0)
309 goto done;
310
311 if ((error = vm_set_register(vcpu, VM_REG_GUEST_SS, gsel)) != 0)
312 goto done;
313
314 /* XXX TR is pointing to the null selector */
315 if ((error = vm_set_register(vcpu, VM_REG_GUEST_TR, 0)) != 0)
316 goto done;
317
318 /* LDTR is pointing to the null selector */
319 if ((error = vm_set_register(vcpu, VM_REG_GUEST_LDTR, 0)) != 0)
320 goto done;
321
322 /* entry point */
323 if ((error = vm_set_register(vcpu, VM_REG_GUEST_RIP, rip)) != 0)
324 goto done;
325
326 /* page table base */
327 if ((error = vm_set_register(vcpu, VM_REG_GUEST_CR3, cr3)) != 0)
328 goto done;
329
330 desc_base = gdtbase;
331 desc_limit = GUEST_GDTR_LIMIT64;
332 error = vm_set_desc(vcpu, VM_REG_GUEST_GDTR,
333 desc_base, desc_limit, 0);
334 if (error != 0)
335 goto done;
336
337 if ((error = vm_set_register(vcpu, VM_REG_GUEST_RSP, rsp)) != 0)
338 goto done;
339
340 error = 0;
341 done:
342 return (error);
343 }
344