xref: /openbmc/linux/arch/x86/kvm/vmx/vmx_ops.h (revision 8ab59da2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __KVM_X86_VMX_INSN_H
3 #define __KVM_X86_VMX_INSN_H
4 
5 #include <linux/nospec.h>
6 
7 #include <asm/vmx.h>
8 
9 #include "evmcs.h"
10 #include "vmcs.h"
11 #include "../x86.h"
12 
13 void vmread_error(unsigned long field, bool fault);
14 __attribute__((regparm(0))) void vmread_error_trampoline(unsigned long field,
15 							 bool fault);
16 void vmwrite_error(unsigned long field, unsigned long value);
17 void vmclear_error(struct vmcs *vmcs, u64 phys_addr);
18 void vmptrld_error(struct vmcs *vmcs, u64 phys_addr);
19 void invvpid_error(unsigned long ext, u16 vpid, gva_t gva);
20 void invept_error(unsigned long ext, u64 eptp, gpa_t gpa);
21 
22 static __always_inline void vmcs_check16(unsigned long field)
23 {
24 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
25 			 "16-bit accessor invalid for 64-bit field");
26 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
27 			 "16-bit accessor invalid for 64-bit high field");
28 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
29 			 "16-bit accessor invalid for 32-bit high field");
30 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
31 			 "16-bit accessor invalid for natural width field");
32 }
33 
34 static __always_inline void vmcs_check32(unsigned long field)
35 {
36 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
37 			 "32-bit accessor invalid for 16-bit field");
38 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
39 			 "32-bit accessor invalid for 64-bit field");
40 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
41 			 "32-bit accessor invalid for 64-bit high field");
42 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
43 			 "32-bit accessor invalid for natural width field");
44 }
45 
46 static __always_inline void vmcs_check64(unsigned long field)
47 {
48 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
49 			 "64-bit accessor invalid for 16-bit field");
50 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
51 			 "64-bit accessor invalid for 64-bit high field");
52 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
53 			 "64-bit accessor invalid for 32-bit field");
54 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
55 			 "64-bit accessor invalid for natural width field");
56 }
57 
58 static __always_inline void vmcs_checkl(unsigned long field)
59 {
60 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
61 			 "Natural width accessor invalid for 16-bit field");
62 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
63 			 "Natural width accessor invalid for 64-bit field");
64 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
65 			 "Natural width accessor invalid for 64-bit high field");
66 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
67 			 "Natural width accessor invalid for 32-bit field");
68 }
69 
70 static __always_inline unsigned long __vmcs_readl(unsigned long field)
71 {
72 	unsigned long value;
73 
74 #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
75 
76 	asm_volatile_goto("1: vmread %[field], %[output]\n\t"
77 			  "jna %l[do_fail]\n\t"
78 
79 			  _ASM_EXTABLE(1b, %l[do_exception])
80 
81 			  : [output] "=r" (value)
82 			  : [field] "r" (field)
83 			  : "cc"
84 			  : do_fail, do_exception);
85 
86 	return value;
87 
88 do_fail:
89 	WARN_ONCE(1, "kvm: vmread failed: field=%lx\n", field);
90 	pr_warn_ratelimited("kvm: vmread failed: field=%lx\n", field);
91 	return 0;
92 
93 do_exception:
94 	kvm_spurious_fault();
95 	return 0;
96 
97 #else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
98 
99 	asm volatile("1: vmread %2, %1\n\t"
100 		     ".byte 0x3e\n\t" /* branch taken hint */
101 		     "ja 3f\n\t"
102 
103 		     /*
104 		      * VMREAD failed.  Push '0' for @fault, push the failing
105 		      * @field, and bounce through the trampoline to preserve
106 		      * volatile registers.
107 		      */
108 		     "xorl %k1, %k1\n\t"
109 		     "2:\n\t"
110 		     "push %1\n\t"
111 		     "push %2\n\t"
112 		     "call vmread_error_trampoline\n\t"
113 
114 		     /*
115 		      * Unwind the stack.  Note, the trampoline zeros out the
116 		      * memory for @fault so that the result is '0' on error.
117 		      */
118 		     "pop %2\n\t"
119 		     "pop %1\n\t"
120 		     "3:\n\t"
121 
122 		     /* VMREAD faulted.  As above, except push '1' for @fault. */
123 		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %1)
124 
125 		     : ASM_CALL_CONSTRAINT, "=&r"(value) : "r"(field) : "cc");
126 	return value;
127 
128 #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
129 }
130 
131 static __always_inline u16 vmcs_read16(unsigned long field)
132 {
133 	vmcs_check16(field);
134 	if (static_branch_unlikely(&enable_evmcs))
135 		return evmcs_read16(field);
136 	return __vmcs_readl(field);
137 }
138 
139 static __always_inline u32 vmcs_read32(unsigned long field)
140 {
141 	vmcs_check32(field);
142 	if (static_branch_unlikely(&enable_evmcs))
143 		return evmcs_read32(field);
144 	return __vmcs_readl(field);
145 }
146 
147 static __always_inline u64 vmcs_read64(unsigned long field)
148 {
149 	vmcs_check64(field);
150 	if (static_branch_unlikely(&enable_evmcs))
151 		return evmcs_read64(field);
152 #ifdef CONFIG_X86_64
153 	return __vmcs_readl(field);
154 #else
155 	return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
156 #endif
157 }
158 
159 static __always_inline unsigned long vmcs_readl(unsigned long field)
160 {
161 	vmcs_checkl(field);
162 	if (static_branch_unlikely(&enable_evmcs))
163 		return evmcs_read64(field);
164 	return __vmcs_readl(field);
165 }
166 
167 #define vmx_asm1(insn, op1, error_args...)				\
168 do {									\
169 	asm_volatile_goto("1: " __stringify(insn) " %0\n\t"		\
170 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
171 			  "jna %l[error]\n\t"				\
172 			  _ASM_EXTABLE(1b, %l[fault])			\
173 			  : : op1 : "cc" : error, fault);		\
174 	return;								\
175 error:									\
176 	instrumentation_begin();					\
177 	insn##_error(error_args);					\
178 	instrumentation_end();						\
179 	return;								\
180 fault:									\
181 	kvm_spurious_fault();						\
182 } while (0)
183 
184 #define vmx_asm2(insn, op1, op2, error_args...)				\
185 do {									\
186 	asm_volatile_goto("1: "  __stringify(insn) " %1, %0\n\t"	\
187 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
188 			  "jna %l[error]\n\t"				\
189 			  _ASM_EXTABLE(1b, %l[fault])			\
190 			  : : op1, op2 : "cc" : error, fault);		\
191 	return;								\
192 error:									\
193 	instrumentation_begin();					\
194 	insn##_error(error_args);					\
195 	instrumentation_end();						\
196 	return;								\
197 fault:									\
198 	kvm_spurious_fault();						\
199 } while (0)
200 
201 static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
202 {
203 	vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
204 }
205 
206 static __always_inline void vmcs_write16(unsigned long field, u16 value)
207 {
208 	vmcs_check16(field);
209 	if (static_branch_unlikely(&enable_evmcs))
210 		return evmcs_write16(field, value);
211 
212 	__vmcs_writel(field, value);
213 }
214 
215 static __always_inline void vmcs_write32(unsigned long field, u32 value)
216 {
217 	vmcs_check32(field);
218 	if (static_branch_unlikely(&enable_evmcs))
219 		return evmcs_write32(field, value);
220 
221 	__vmcs_writel(field, value);
222 }
223 
224 static __always_inline void vmcs_write64(unsigned long field, u64 value)
225 {
226 	vmcs_check64(field);
227 	if (static_branch_unlikely(&enable_evmcs))
228 		return evmcs_write64(field, value);
229 
230 	__vmcs_writel(field, value);
231 #ifndef CONFIG_X86_64
232 	__vmcs_writel(field+1, value >> 32);
233 #endif
234 }
235 
236 static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
237 {
238 	vmcs_checkl(field);
239 	if (static_branch_unlikely(&enable_evmcs))
240 		return evmcs_write64(field, value);
241 
242 	__vmcs_writel(field, value);
243 }
244 
245 static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
246 {
247 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
248 			 "vmcs_clear_bits does not support 64-bit fields");
249 	if (static_branch_unlikely(&enable_evmcs))
250 		return evmcs_write32(field, evmcs_read32(field) & ~mask);
251 
252 	__vmcs_writel(field, __vmcs_readl(field) & ~mask);
253 }
254 
255 static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
256 {
257 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
258 			 "vmcs_set_bits does not support 64-bit fields");
259 	if (static_branch_unlikely(&enable_evmcs))
260 		return evmcs_write32(field, evmcs_read32(field) | mask);
261 
262 	__vmcs_writel(field, __vmcs_readl(field) | mask);
263 }
264 
265 static inline void vmcs_clear(struct vmcs *vmcs)
266 {
267 	u64 phys_addr = __pa(vmcs);
268 
269 	vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
270 }
271 
272 static inline void vmcs_load(struct vmcs *vmcs)
273 {
274 	u64 phys_addr = __pa(vmcs);
275 
276 	if (static_branch_unlikely(&enable_evmcs))
277 		return evmcs_load(phys_addr);
278 
279 	vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
280 }
281 
282 static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
283 {
284 	struct {
285 		u64 vpid : 16;
286 		u64 rsvd : 48;
287 		u64 gva;
288 	} operand = { vpid, 0, gva };
289 
290 	vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
291 }
292 
293 static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
294 {
295 	struct {
296 		u64 eptp, gpa;
297 	} operand = {eptp, gpa};
298 
299 	vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa);
300 }
301 
302 static inline void vpid_sync_vcpu_single(int vpid)
303 {
304 	if (vpid == 0)
305 		return;
306 
307 	__invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
308 }
309 
310 static inline void vpid_sync_vcpu_global(void)
311 {
312 	__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
313 }
314 
315 static inline void vpid_sync_context(int vpid)
316 {
317 	if (cpu_has_vmx_invvpid_single())
318 		vpid_sync_vcpu_single(vpid);
319 	else if (vpid != 0)
320 		vpid_sync_vcpu_global();
321 }
322 
323 static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
324 {
325 	if (vpid == 0)
326 		return;
327 
328 	if (cpu_has_vmx_invvpid_individual_addr())
329 		__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
330 	else
331 		vpid_sync_context(vpid);
332 }
333 
334 static inline void ept_sync_global(void)
335 {
336 	__invept(VMX_EPT_EXTENT_GLOBAL, 0, 0);
337 }
338 
339 static inline void ept_sync_context(u64 eptp)
340 {
341 	if (cpu_has_vmx_invept_context())
342 		__invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0);
343 	else
344 		ept_sync_global();
345 }
346 
347 #endif /* __KVM_X86_VMX_INSN_H */
348