xref: /openbmc/linux/arch/x86/kvm/vmx/vmx_ops.h (revision 1edd0337)
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 "hyperv.h"
10 #include "vmcs.h"
11 #include "../x86.h"
12 
13 void vmread_error(unsigned long field, bool fault);
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, gpa_t gpa);
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 #endif
35 
36 static __always_inline void vmcs_check16(unsigned long field)
37 {
38 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
39 			 "16-bit accessor invalid for 64-bit field");
40 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
41 			 "16-bit accessor invalid for 64-bit high field");
42 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
43 			 "16-bit accessor invalid for 32-bit high field");
44 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
45 			 "16-bit accessor invalid for natural width field");
46 }
47 
48 static __always_inline void vmcs_check32(unsigned long field)
49 {
50 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
51 			 "32-bit accessor invalid for 16-bit field");
52 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
53 			 "32-bit accessor invalid for 64-bit field");
54 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
55 			 "32-bit accessor invalid for 64-bit high field");
56 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
57 			 "32-bit accessor invalid for natural width field");
58 }
59 
60 static __always_inline void vmcs_check64(unsigned long field)
61 {
62 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
63 			 "64-bit accessor invalid for 16-bit field");
64 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
65 			 "64-bit accessor invalid for 64-bit high field");
66 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
67 			 "64-bit accessor invalid for 32-bit field");
68 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
69 			 "64-bit accessor invalid for natural width field");
70 }
71 
72 static __always_inline void vmcs_checkl(unsigned long field)
73 {
74 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
75 			 "Natural width accessor invalid for 16-bit field");
76 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
77 			 "Natural width accessor invalid for 64-bit field");
78 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
79 			 "Natural width accessor invalid for 64-bit high field");
80 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
81 			 "Natural width accessor invalid for 32-bit field");
82 }
83 
84 static __always_inline unsigned long __vmcs_readl(unsigned long field)
85 {
86 	unsigned long value;
87 
88 #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT
89 
90 	asm_volatile_goto("1: vmread %[field], %[output]\n\t"
91 			  "jna %l[do_fail]\n\t"
92 
93 			  _ASM_EXTABLE(1b, %l[do_exception])
94 
95 			  : [output] "=r" (value)
96 			  : [field] "r" (field)
97 			  : "cc"
98 			  : do_fail, do_exception);
99 
100 	return value;
101 
102 do_fail:
103 	instrumentation_begin();
104 	WARN_ONCE(1, KBUILD_MODNAME ": vmread failed: field=%lx\n", field);
105 	pr_warn_ratelimited(KBUILD_MODNAME ": vmread failed: field=%lx\n", field);
106 	instrumentation_end();
107 	return 0;
108 
109 do_exception:
110 	kvm_spurious_fault();
111 	return 0;
112 
113 #else /* !CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
114 
115 	asm volatile("1: vmread %2, %1\n\t"
116 		     ".byte 0x3e\n\t" /* branch taken hint */
117 		     "ja 3f\n\t"
118 
119 		     /*
120 		      * VMREAD failed.  Push '0' for @fault, push the failing
121 		      * @field, and bounce through the trampoline to preserve
122 		      * volatile registers.
123 		      */
124 		     "xorl %k1, %k1\n\t"
125 		     "2:\n\t"
126 		     "push %1\n\t"
127 		     "push %2\n\t"
128 		     "call vmread_error_trampoline\n\t"
129 
130 		     /*
131 		      * Unwind the stack.  Note, the trampoline zeros out the
132 		      * memory for @fault so that the result is '0' on error.
133 		      */
134 		     "pop %2\n\t"
135 		     "pop %1\n\t"
136 		     "3:\n\t"
137 
138 		     /* VMREAD faulted.  As above, except push '1' for @fault. */
139 		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %1)
140 
141 		     : ASM_CALL_CONSTRAINT, "=&r"(value) : "r"(field) : "cc");
142 	return value;
143 
144 #endif /* CONFIG_CC_HAS_ASM_GOTO_OUTPUT */
145 }
146 
147 static __always_inline u16 vmcs_read16(unsigned long field)
148 {
149 	vmcs_check16(field);
150 	if (static_branch_unlikely(&enable_evmcs))
151 		return evmcs_read16(field);
152 	return __vmcs_readl(field);
153 }
154 
155 static __always_inline u32 vmcs_read32(unsigned long field)
156 {
157 	vmcs_check32(field);
158 	if (static_branch_unlikely(&enable_evmcs))
159 		return evmcs_read32(field);
160 	return __vmcs_readl(field);
161 }
162 
163 static __always_inline u64 vmcs_read64(unsigned long field)
164 {
165 	vmcs_check64(field);
166 	if (static_branch_unlikely(&enable_evmcs))
167 		return evmcs_read64(field);
168 #ifdef CONFIG_X86_64
169 	return __vmcs_readl(field);
170 #else
171 	return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
172 #endif
173 }
174 
175 static __always_inline unsigned long vmcs_readl(unsigned long field)
176 {
177 	vmcs_checkl(field);
178 	if (static_branch_unlikely(&enable_evmcs))
179 		return evmcs_read64(field);
180 	return __vmcs_readl(field);
181 }
182 
183 #define vmx_asm1(insn, op1, error_args...)				\
184 do {									\
185 	asm_volatile_goto("1: " __stringify(insn) " %0\n\t"		\
186 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
187 			  "jna %l[error]\n\t"				\
188 			  _ASM_EXTABLE(1b, %l[fault])			\
189 			  : : op1 : "cc" : error, fault);		\
190 	return;								\
191 error:									\
192 	instrumentation_begin();					\
193 	insn##_error(error_args);					\
194 	instrumentation_end();						\
195 	return;								\
196 fault:									\
197 	kvm_spurious_fault();						\
198 } while (0)
199 
200 #define vmx_asm2(insn, op1, op2, error_args...)				\
201 do {									\
202 	asm_volatile_goto("1: "  __stringify(insn) " %1, %0\n\t"	\
203 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
204 			  "jna %l[error]\n\t"				\
205 			  _ASM_EXTABLE(1b, %l[fault])			\
206 			  : : op1, op2 : "cc" : error, fault);		\
207 	return;								\
208 error:									\
209 	instrumentation_begin();					\
210 	insn##_error(error_args);					\
211 	instrumentation_end();						\
212 	return;								\
213 fault:									\
214 	kvm_spurious_fault();						\
215 } while (0)
216 
217 static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
218 {
219 	vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
220 }
221 
222 static __always_inline void vmcs_write16(unsigned long field, u16 value)
223 {
224 	vmcs_check16(field);
225 	if (static_branch_unlikely(&enable_evmcs))
226 		return evmcs_write16(field, value);
227 
228 	__vmcs_writel(field, value);
229 }
230 
231 static __always_inline void vmcs_write32(unsigned long field, u32 value)
232 {
233 	vmcs_check32(field);
234 	if (static_branch_unlikely(&enable_evmcs))
235 		return evmcs_write32(field, value);
236 
237 	__vmcs_writel(field, value);
238 }
239 
240 static __always_inline void vmcs_write64(unsigned long field, u64 value)
241 {
242 	vmcs_check64(field);
243 	if (static_branch_unlikely(&enable_evmcs))
244 		return evmcs_write64(field, value);
245 
246 	__vmcs_writel(field, value);
247 #ifndef CONFIG_X86_64
248 	__vmcs_writel(field+1, value >> 32);
249 #endif
250 }
251 
252 static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
253 {
254 	vmcs_checkl(field);
255 	if (static_branch_unlikely(&enable_evmcs))
256 		return evmcs_write64(field, value);
257 
258 	__vmcs_writel(field, value);
259 }
260 
261 static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
262 {
263 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
264 			 "vmcs_clear_bits does not support 64-bit fields");
265 	if (static_branch_unlikely(&enable_evmcs))
266 		return evmcs_write32(field, evmcs_read32(field) & ~mask);
267 
268 	__vmcs_writel(field, __vmcs_readl(field) & ~mask);
269 }
270 
271 static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
272 {
273 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
274 			 "vmcs_set_bits does not support 64-bit fields");
275 	if (static_branch_unlikely(&enable_evmcs))
276 		return evmcs_write32(field, evmcs_read32(field) | mask);
277 
278 	__vmcs_writel(field, __vmcs_readl(field) | mask);
279 }
280 
281 static inline void vmcs_clear(struct vmcs *vmcs)
282 {
283 	u64 phys_addr = __pa(vmcs);
284 
285 	vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
286 }
287 
288 static inline void vmcs_load(struct vmcs *vmcs)
289 {
290 	u64 phys_addr = __pa(vmcs);
291 
292 	if (static_branch_unlikely(&enable_evmcs))
293 		return evmcs_load(phys_addr);
294 
295 	vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
296 }
297 
298 static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
299 {
300 	struct {
301 		u64 vpid : 16;
302 		u64 rsvd : 48;
303 		u64 gva;
304 	} operand = { vpid, 0, gva };
305 
306 	vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
307 }
308 
309 static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
310 {
311 	struct {
312 		u64 eptp, gpa;
313 	} operand = {eptp, gpa};
314 
315 	vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa);
316 }
317 
318 static inline void vpid_sync_vcpu_single(int vpid)
319 {
320 	if (vpid == 0)
321 		return;
322 
323 	__invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
324 }
325 
326 static inline void vpid_sync_vcpu_global(void)
327 {
328 	__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
329 }
330 
331 static inline void vpid_sync_context(int vpid)
332 {
333 	if (cpu_has_vmx_invvpid_single())
334 		vpid_sync_vcpu_single(vpid);
335 	else if (vpid != 0)
336 		vpid_sync_vcpu_global();
337 }
338 
339 static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
340 {
341 	if (vpid == 0)
342 		return;
343 
344 	if (cpu_has_vmx_invvpid_individual_addr())
345 		__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
346 	else
347 		vpid_sync_context(vpid);
348 }
349 
350 static inline void ept_sync_global(void)
351 {
352 	__invept(VMX_EPT_EXTENT_GLOBAL, 0, 0);
353 }
354 
355 static inline void ept_sync_context(u64 eptp)
356 {
357 	if (cpu_has_vmx_invept_context())
358 		__invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0);
359 	else
360 		ept_sync_global();
361 }
362 
363 #endif /* __KVM_X86_VMX_INSN_H */
364