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 "vmx_onhyperv.h"
10 #include "vmcs.h"
11 #include "../x86.h"
12 
13 void vmread_error(unsigned long field);
14 void vmwrite_error(unsigned long field, unsigned long value);
15 void vmclear_error(struct vmcs *vmcs, u64 phys_addr);
16 void vmptrld_error(struct vmcs *vmcs, u64 phys_addr);
17 void invvpid_error(unsigned long ext, u16 vpid, gva_t gva);
18 void invept_error(unsigned long ext, u64 eptp);
19 
20 #ifndef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
21 /*
22  * The VMREAD error trampoline _always_ uses the stack to pass parameters, even
23  * for 64-bit targets.  Preserving all registers allows the VMREAD inline asm
24  * blob to avoid clobbering GPRs, which in turn allows the compiler to better
25  * optimize sequences of VMREADs.
26  *
27  * Declare the trampoline as an opaque label as it's not safe to call from C
28  * code; there is no way to tell the compiler to pass params on the stack for
29  * 64-bit targets.
30  *
31  * void vmread_error_trampoline(unsigned long field, bool fault);
32  */
33 extern unsigned long vmread_error_trampoline;
34 
35 /*
36  * The second VMREAD error trampoline, called from the assembly trampoline,
37  * exists primarily to enable instrumentation for the VM-Fail path.
38  */
39 void vmread_error_trampoline2(unsigned long field, bool fault);
40 
41 #endif
42 
vmcs_check16(unsigned long field)43 static __always_inline void vmcs_check16(unsigned long field)
44 {
45 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
46 			 "16-bit accessor invalid for 64-bit field");
47 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
48 			 "16-bit accessor invalid for 64-bit high field");
49 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
50 			 "16-bit accessor invalid for 32-bit field");
51 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
52 			 "16-bit accessor invalid for natural width field");
53 }
54 
vmcs_check32(unsigned long field)55 static __always_inline void vmcs_check32(unsigned long field)
56 {
57 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
58 			 "32-bit accessor invalid for 16-bit field");
59 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
60 			 "32-bit accessor invalid for 64-bit field");
61 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
62 			 "32-bit accessor invalid for 64-bit high field");
63 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
64 			 "32-bit accessor invalid for natural width field");
65 }
66 
vmcs_check64(unsigned long field)67 static __always_inline void vmcs_check64(unsigned long field)
68 {
69 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
70 			 "64-bit accessor invalid for 16-bit field");
71 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
72 			 "64-bit accessor invalid for 64-bit high field");
73 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
74 			 "64-bit accessor invalid for 32-bit field");
75 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
76 			 "64-bit accessor invalid for natural width field");
77 }
78 
vmcs_checkl(unsigned long field)79 static __always_inline void vmcs_checkl(unsigned long field)
80 {
81 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
82 			 "Natural width accessor invalid for 16-bit field");
83 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
84 			 "Natural width accessor invalid for 64-bit field");
85 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
86 			 "Natural width accessor invalid for 64-bit high field");
87 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
88 			 "Natural width accessor invalid for 32-bit field");
89 }
90 
__vmcs_readl(unsigned long field)91 static __always_inline unsigned long __vmcs_readl(unsigned long field)
92 {
93 	unsigned long value;
94 
95 #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
96 
97 	asm_goto_output("1: vmread %[field], %[output]\n\t"
98 			  "jna %l[do_fail]\n\t"
99 
100 			  _ASM_EXTABLE(1b, %l[do_exception])
101 
102 			  : [output] "=r" (value)
103 			  : [field] "r" (field)
104 			  : "cc"
105 			  : do_fail, do_exception);
106 
107 	return value;
108 
109 do_fail:
110 	instrumentation_begin();
111 	vmread_error(field);
112 	instrumentation_end();
113 	return 0;
114 
115 do_exception:
116 	kvm_spurious_fault();
117 	return 0;
118 
119 #else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
120 
121 	asm volatile("1: vmread %[field], %[output]\n\t"
122 		     ".byte 0x3e\n\t" /* branch taken hint */
123 		     "ja 3f\n\t"
124 
125 		     /*
126 		      * VMREAD failed.  Push '0' for @fault, push the failing
127 		      * @field, and bounce through the trampoline to preserve
128 		      * volatile registers.
129 		      */
130 		     "xorl %k[output], %k[output]\n\t"
131 		     "2:\n\t"
132 		     "push %[output]\n\t"
133 		     "push %[field]\n\t"
134 		     "call vmread_error_trampoline\n\t"
135 
136 		     /*
137 		      * Unwind the stack.  Note, the trampoline zeros out the
138 		      * memory for @fault so that the result is '0' on error.
139 		      */
140 		     "pop %[field]\n\t"
141 		     "pop %[output]\n\t"
142 		     "3:\n\t"
143 
144 		     /* VMREAD faulted.  As above, except push '1' for @fault. */
145 		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %[output])
146 
147 		     : ASM_CALL_CONSTRAINT, [output] "=&r" (value)
148 		     : [field] "r" (field)
149 		     : "cc");
150 	return value;
151 
152 #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
153 }
154 
vmcs_read16(unsigned long field)155 static __always_inline u16 vmcs_read16(unsigned long field)
156 {
157 	vmcs_check16(field);
158 	if (kvm_is_using_evmcs())
159 		return evmcs_read16(field);
160 	return __vmcs_readl(field);
161 }
162 
vmcs_read32(unsigned long field)163 static __always_inline u32 vmcs_read32(unsigned long field)
164 {
165 	vmcs_check32(field);
166 	if (kvm_is_using_evmcs())
167 		return evmcs_read32(field);
168 	return __vmcs_readl(field);
169 }
170 
vmcs_read64(unsigned long field)171 static __always_inline u64 vmcs_read64(unsigned long field)
172 {
173 	vmcs_check64(field);
174 	if (kvm_is_using_evmcs())
175 		return evmcs_read64(field);
176 #ifdef CONFIG_X86_64
177 	return __vmcs_readl(field);
178 #else
179 	return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
180 #endif
181 }
182 
vmcs_readl(unsigned long field)183 static __always_inline unsigned long vmcs_readl(unsigned long field)
184 {
185 	vmcs_checkl(field);
186 	if (kvm_is_using_evmcs())
187 		return evmcs_read64(field);
188 	return __vmcs_readl(field);
189 }
190 
191 #define vmx_asm1(insn, op1, error_args...)				\
192 do {									\
193 	asm goto("1: " __stringify(insn) " %0\n\t"			\
194 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
195 			  "jna %l[error]\n\t"				\
196 			  _ASM_EXTABLE(1b, %l[fault])			\
197 			  : : op1 : "cc" : error, fault);		\
198 	return;								\
199 error:									\
200 	instrumentation_begin();					\
201 	insn##_error(error_args);					\
202 	instrumentation_end();						\
203 	return;								\
204 fault:									\
205 	kvm_spurious_fault();						\
206 } while (0)
207 
208 #define vmx_asm2(insn, op1, op2, error_args...)				\
209 do {									\
210 	asm goto("1: "  __stringify(insn) " %1, %0\n\t"			\
211 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
212 			  "jna %l[error]\n\t"				\
213 			  _ASM_EXTABLE(1b, %l[fault])			\
214 			  : : op1, op2 : "cc" : error, fault);		\
215 	return;								\
216 error:									\
217 	instrumentation_begin();					\
218 	insn##_error(error_args);					\
219 	instrumentation_end();						\
220 	return;								\
221 fault:									\
222 	kvm_spurious_fault();						\
223 } while (0)
224 
__vmcs_writel(unsigned long field,unsigned long value)225 static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
226 {
227 	vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
228 }
229 
vmcs_write16(unsigned long field,u16 value)230 static __always_inline void vmcs_write16(unsigned long field, u16 value)
231 {
232 	vmcs_check16(field);
233 	if (kvm_is_using_evmcs())
234 		return evmcs_write16(field, value);
235 
236 	__vmcs_writel(field, value);
237 }
238 
vmcs_write32(unsigned long field,u32 value)239 static __always_inline void vmcs_write32(unsigned long field, u32 value)
240 {
241 	vmcs_check32(field);
242 	if (kvm_is_using_evmcs())
243 		return evmcs_write32(field, value);
244 
245 	__vmcs_writel(field, value);
246 }
247 
vmcs_write64(unsigned long field,u64 value)248 static __always_inline void vmcs_write64(unsigned long field, u64 value)
249 {
250 	vmcs_check64(field);
251 	if (kvm_is_using_evmcs())
252 		return evmcs_write64(field, value);
253 
254 	__vmcs_writel(field, value);
255 #ifndef CONFIG_X86_64
256 	__vmcs_writel(field+1, value >> 32);
257 #endif
258 }
259 
vmcs_writel(unsigned long field,unsigned long value)260 static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
261 {
262 	vmcs_checkl(field);
263 	if (kvm_is_using_evmcs())
264 		return evmcs_write64(field, value);
265 
266 	__vmcs_writel(field, value);
267 }
268 
vmcs_clear_bits(unsigned long field,u32 mask)269 static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
270 {
271 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
272 			 "vmcs_clear_bits does not support 64-bit fields");
273 	if (kvm_is_using_evmcs())
274 		return evmcs_write32(field, evmcs_read32(field) & ~mask);
275 
276 	__vmcs_writel(field, __vmcs_readl(field) & ~mask);
277 }
278 
vmcs_set_bits(unsigned long field,u32 mask)279 static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
280 {
281 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
282 			 "vmcs_set_bits does not support 64-bit fields");
283 	if (kvm_is_using_evmcs())
284 		return evmcs_write32(field, evmcs_read32(field) | mask);
285 
286 	__vmcs_writel(field, __vmcs_readl(field) | mask);
287 }
288 
vmcs_clear(struct vmcs * vmcs)289 static inline void vmcs_clear(struct vmcs *vmcs)
290 {
291 	u64 phys_addr = __pa(vmcs);
292 
293 	vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
294 }
295 
vmcs_load(struct vmcs * vmcs)296 static inline void vmcs_load(struct vmcs *vmcs)
297 {
298 	u64 phys_addr = __pa(vmcs);
299 
300 	if (kvm_is_using_evmcs())
301 		return evmcs_load(phys_addr);
302 
303 	vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
304 }
305 
__invvpid(unsigned long ext,u16 vpid,gva_t gva)306 static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
307 {
308 	struct {
309 		u64 vpid : 16;
310 		u64 rsvd : 48;
311 		u64 gva;
312 	} operand = { vpid, 0, gva };
313 
314 	vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
315 }
316 
__invept(unsigned long ext,u64 eptp)317 static inline void __invept(unsigned long ext, u64 eptp)
318 {
319 	struct {
320 		u64 eptp;
321 		u64 reserved_0;
322 	} operand = { eptp, 0 };
323 	vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp);
324 }
325 
vpid_sync_vcpu_single(int vpid)326 static inline void vpid_sync_vcpu_single(int vpid)
327 {
328 	if (vpid == 0)
329 		return;
330 
331 	__invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
332 }
333 
vpid_sync_vcpu_global(void)334 static inline void vpid_sync_vcpu_global(void)
335 {
336 	__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
337 }
338 
vpid_sync_context(int vpid)339 static inline void vpid_sync_context(int vpid)
340 {
341 	if (cpu_has_vmx_invvpid_single())
342 		vpid_sync_vcpu_single(vpid);
343 	else if (vpid != 0)
344 		vpid_sync_vcpu_global();
345 }
346 
vpid_sync_vcpu_addr(int vpid,gva_t addr)347 static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
348 {
349 	if (vpid == 0)
350 		return;
351 
352 	if (cpu_has_vmx_invvpid_individual_addr())
353 		__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
354 	else
355 		vpid_sync_context(vpid);
356 }
357 
ept_sync_global(void)358 static inline void ept_sync_global(void)
359 {
360 	__invept(VMX_EPT_EXTENT_GLOBAL, 0);
361 }
362 
ept_sync_context(u64 eptp)363 static inline void ept_sync_context(u64 eptp)
364 {
365 	if (cpu_has_vmx_invept_context())
366 		__invept(VMX_EPT_EXTENT_CONTEXT, eptp);
367 	else
368 		ept_sync_global();
369 }
370 
371 #endif /* __KVM_X86_VMX_INSN_H */
372