summaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/vmx/vmx_ops.h
blob: 6a0c6e81f7f3e7e1f94a15089d54edc1e53902d1 (plain)
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
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __KVM_X86_VMX_INSN_H
#define __KVM_X86_VMX_INSN_H

#include <linux/nospec.h>

#include <asm/vmx.h>

#include "hyperv.h"
#include "vmcs.h"
#include "../x86.h"

void vmread_error(unsigned long field);
void vmwrite_error(unsigned long field, unsigned long value);
void vmclear_error(struct vmcs *vmcs, u64 phys_addr);
void vmptrld_error(struct vmcs *vmcs, u64 phys_addr);
void invvpid_error(unsigned long ext, u16 vpid, gva_t gva);
void invept_error(unsigned long ext, u64 eptp, gpa_t gpa);

#ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
/*
 * The VMREAD error trampoline _always_ uses the stack to pass parameters, even
 * for 64-bit targets.  Preserving all registers allows the VMREAD inline asm
 * blob to avoid clobbering GPRs, which in turn allows the compiler to better
 * optimize sequences of VMREADs.
 *
 * Declare the trampoline as an opaque label as it's not safe to call from C
 * code; there is no way to tell the compiler to pass params on the stack for
 * 64-bit targets.
 *
 * void vmread_error_trampoline(unsigned long field, bool fault);
 */
extern unsigned long vmread_error_trampoline;

/*
 * The second VMREAD error trampoline, called from the assembly trampoline,
 * exists primarily to enable instrumentation for the VM-Fail path.
 */
void vmread_error_trampoline2(unsigned long field, bool fault);

#endif

static __always_inline void vmcs_check16(unsigned long field)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
			 "16-bit accessor invalid for 64-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
			 "16-bit accessor invalid for 64-bit high field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
			 "16-bit accessor invalid for 32-bit high field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
			 "16-bit accessor invalid for natural width field");
}

static __always_inline void vmcs_check32(unsigned long field)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
			 "32-bit accessor invalid for 16-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
			 "32-bit accessor invalid for 64-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
			 "32-bit accessor invalid for 64-bit high field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
			 "32-bit accessor invalid for natural width field");
}

static __always_inline void vmcs_check64(unsigned long field)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
			 "64-bit accessor invalid for 16-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
			 "64-bit accessor invalid for 64-bit high field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
			 "64-bit accessor invalid for 32-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
			 "64-bit accessor invalid for natural width field");
}

static __always_inline void vmcs_checkl(unsigned long field)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
			 "Natural width accessor invalid for 16-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
			 "Natural width accessor invalid for 64-bit field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
			 "Natural width accessor invalid for 64-bit high field");
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
			 "Natural width accessor invalid for 32-bit field");
}

static __always_inline unsigned long __vmcs_readl(unsigned long field)
{
	unsigned long value;

#ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT

	asm_goto_output("1: vmread %[field], %[output]\n\t"
			  "jna %l[do_fail]\n\t"

			  _ASM_EXTABLE(1b, %l[do_exception])

			  : [output] "=r" (value)
			  : [field] "r" (field)
			  : "cc"
			  : do_fail, do_exception);

	return value;

do_fail:
	instrumentation_begin();
	vmread_error(field);
	instrumentation_end();
	return 0;

do_exception:
	kvm_spurious_fault();
	return 0;

#else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */

	asm volatile("1: vmread %2, %1\n\t"
		     ".byte 0x3e\n\t" /* branch taken hint */
		     "ja 3f\n\t"

		     /*
		      * VMREAD failed.  Push '0' for @fault, push the failing
		      * @field, and bounce through the trampoline to preserve
		      * volatile registers.
		      */
		     "xorl %k1, %k1\n\t"
		     "2:\n\t"
		     "push %1\n\t"
		     "push %2\n\t"
		     "call vmread_error_trampoline\n\t"

		     /*
		      * Unwind the stack.  Note, the trampoline zeros out the
		      * memory for @fault so that the result is '0' on error.
		      */
		     "pop %2\n\t"
		     "pop %1\n\t"
		     "3:\n\t"

		     /* VMREAD faulted.  As above, except push '1' for @fault. */
		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %1)

		     : ASM_CALL_CONSTRAINT, "=&r"(value) : "r"(field) : "cc");
	return value;

#endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
}

static __always_inline u16 vmcs_read16(unsigned long field)
{
	vmcs_check16(field);
	if (kvm_is_using_evmcs())
		return evmcs_read16(field);
	return __vmcs_readl(field);
}

static __always_inline u32 vmcs_read32(unsigned long field)
{
	vmcs_check32(field);
	if (kvm_is_using_evmcs())
		return evmcs_read32(field);
	return __vmcs_readl(field);
}

static __always_inline u64 vmcs_read64(unsigned long field)
{
	vmcs_check64(field);
	if (kvm_is_using_evmcs())
		return evmcs_read64(field);
#ifdef CONFIG_X86_64
	return __vmcs_readl(field);
#else
	return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
#endif
}

static __always_inline unsigned long vmcs_readl(unsigned long field)
{
	vmcs_checkl(field);
	if (kvm_is_using_evmcs())
		return evmcs_read64(field);
	return __vmcs_readl(field);
}

#define vmx_asm1(insn, op1, error_args...)				\
do {									\
	asm goto("1: " __stringify(insn) " %0\n\t"			\
			  ".byte 0x2e\n\t" /* branch not taken hint */	\
			  "jna %l[error]\n\t"				\
			  _ASM_EXTABLE(1b, %l[fault])			\
			  : : op1 : "cc" : error, fault);		\
	return;								\
error:									\
	instrumentation_begin();					\
	insn##_error(error_args);					\
	instrumentation_end();						\
	return;								\
fault:									\
	kvm_spurious_fault();						\
} while (0)

#define vmx_asm2(insn, op1, op2, error_args...)				\
do {									\
	asm goto("1: "  __stringify(insn) " %1, %0\n\t"			\
			  ".byte 0x2e\n\t" /* branch not taken hint */	\
			  "jna %l[error]\n\t"				\
			  _ASM_EXTABLE(1b, %l[fault])			\
			  : : op1, op2 : "cc" : error, fault);		\
	return;								\
error:									\
	instrumentation_begin();					\
	insn##_error(error_args);					\
	instrumentation_end();						\
	return;								\
fault:									\
	kvm_spurious_fault();						\
} while (0)

static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
{
	vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
}

static __always_inline void vmcs_write16(unsigned long field, u16 value)
{
	vmcs_check16(field);
	if (kvm_is_using_evmcs())
		return evmcs_write16(field, value);

	__vmcs_writel(field, value);
}

static __always_inline void vmcs_write32(unsigned long field, u32 value)
{
	vmcs_check32(field);
	if (kvm_is_using_evmcs())
		return evmcs_write32(field, value);

	__vmcs_writel(field, value);
}

static __always_inline void vmcs_write64(unsigned long field, u64 value)
{
	vmcs_check64(field);
	if (kvm_is_using_evmcs())
		return evmcs_write64(field, value);

	__vmcs_writel(field, value);
#ifndef CONFIG_X86_64
	__vmcs_writel(field+1, value >> 32);
#endif
}

static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
{
	vmcs_checkl(field);
	if (kvm_is_using_evmcs())
		return evmcs_write64(field, value);

	__vmcs_writel(field, value);
}

static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
			 "vmcs_clear_bits does not support 64-bit fields");
	if (kvm_is_using_evmcs())
		return evmcs_write32(field, evmcs_read32(field) & ~mask);

	__vmcs_writel(field, __vmcs_readl(field) & ~mask);
}

static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
{
	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
			 "vmcs_set_bits does not support 64-bit fields");
	if (kvm_is_using_evmcs())
		return evmcs_write32(field, evmcs_read32(field) | mask);

	__vmcs_writel(field, __vmcs_readl(field) | mask);
}

static inline void vmcs_clear(struct vmcs *vmcs)
{
	u64 phys_addr = __pa(vmcs);

	vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
}

static inline void vmcs_load(struct vmcs *vmcs)
{
	u64 phys_addr = __pa(vmcs);

	if (kvm_is_using_evmcs())
		return evmcs_load(phys_addr);

	vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
}

static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
{
	struct {
		u64 vpid : 16;
		u64 rsvd : 48;
		u64 gva;
	} operand = { vpid, 0, gva };

	vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
}

static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
{
	struct {
		u64 eptp, gpa;
	} operand = {eptp, gpa};

	vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa);
}

static inline void vpid_sync_vcpu_single(int vpid)
{
	if (vpid == 0)
		return;

	__invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
}

static inline void vpid_sync_vcpu_global(void)
{
	__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
}

static inline void vpid_sync_context(int vpid)
{
	if (cpu_has_vmx_invvpid_single())
		vpid_sync_vcpu_single(vpid);
	else if (vpid != 0)
		vpid_sync_vcpu_global();
}

static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
{
	if (vpid == 0)
		return;

	if (cpu_has_vmx_invvpid_individual_addr())
		__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
	else
		vpid_sync_context(vpid);
}

static inline void ept_sync_global(void)
{
	__invept(VMX_EPT_EXTENT_GLOBAL, 0, 0);
}

static inline void ept_sync_context(u64 eptp)
{
	if (cpu_has_vmx_invept_context())
		__invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0);
	else
		ept_sync_global();
}

#endif /* __KVM_X86_VMX_INSN_H */