xref: /openbmc/linux/arch/x86/kvm/vmx/vmx_ops.h (revision 6f4eaea2)
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/kvm_host.h>
8 #include <asm/vmx.h>
9 
10 #include "evmcs.h"
11 #include "vmcs.h"
12 
13 #define __ex(x) __kvm_handle_fault_on_reboot(x)
14 
15 asmlinkage void vmread_error(unsigned long field, bool fault);
16 __attribute__((regparm(0))) void vmread_error_trampoline(unsigned long field,
17 							 bool fault);
18 void vmwrite_error(unsigned long field, unsigned long value);
19 void vmclear_error(struct vmcs *vmcs, u64 phys_addr);
20 void vmptrld_error(struct vmcs *vmcs, u64 phys_addr);
21 void invvpid_error(unsigned long ext, u16 vpid, gva_t gva);
22 void invept_error(unsigned long ext, u64 eptp, gpa_t gpa);
23 
24 static __always_inline void vmcs_check16(unsigned long field)
25 {
26 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
27 			 "16-bit accessor invalid for 64-bit field");
28 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
29 			 "16-bit accessor invalid for 64-bit high field");
30 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
31 			 "16-bit accessor invalid for 32-bit high field");
32 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
33 			 "16-bit accessor invalid for natural width field");
34 }
35 
36 static __always_inline void vmcs_check32(unsigned long field)
37 {
38 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
39 			 "32-bit accessor invalid for 16-bit field");
40 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
41 			 "32-bit accessor invalid for natural width field");
42 }
43 
44 static __always_inline void vmcs_check64(unsigned long field)
45 {
46 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
47 			 "64-bit accessor invalid for 16-bit field");
48 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
49 			 "64-bit accessor invalid for 64-bit high field");
50 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
51 			 "64-bit accessor invalid for 32-bit field");
52 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x6000,
53 			 "64-bit accessor invalid for natural width field");
54 }
55 
56 static __always_inline void vmcs_checkl(unsigned long field)
57 {
58 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0,
59 			 "Natural width accessor invalid for 16-bit field");
60 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2000,
61 			 "Natural width accessor invalid for 64-bit field");
62 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6001) == 0x2001,
63 			 "Natural width accessor invalid for 64-bit high field");
64 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x4000,
65 			 "Natural width accessor invalid for 32-bit field");
66 }
67 
68 static __always_inline unsigned long __vmcs_readl(unsigned long field)
69 {
70 	unsigned long value;
71 
72 	asm volatile("1: vmread %2, %1\n\t"
73 		     ".byte 0x3e\n\t" /* branch taken hint */
74 		     "ja 3f\n\t"
75 
76 		     /*
77 		      * VMREAD failed.  Push '0' for @fault, push the failing
78 		      * @field, and bounce through the trampoline to preserve
79 		      * volatile registers.
80 		      */
81 		     "push $0\n\t"
82 		     "push %2\n\t"
83 		     "2:call vmread_error_trampoline\n\t"
84 
85 		     /*
86 		      * Unwind the stack.  Note, the trampoline zeros out the
87 		      * memory for @fault so that the result is '0' on error.
88 		      */
89 		     "pop %2\n\t"
90 		     "pop %1\n\t"
91 		     "3:\n\t"
92 
93 		     /* VMREAD faulted.  As above, except push '1' for @fault. */
94 		     ".pushsection .fixup, \"ax\"\n\t"
95 		     "4: push $1\n\t"
96 		     "push %2\n\t"
97 		     "jmp 2b\n\t"
98 		     ".popsection\n\t"
99 		     _ASM_EXTABLE(1b, 4b)
100 		     : ASM_CALL_CONSTRAINT, "=r"(value) : "r"(field) : "cc");
101 	return value;
102 }
103 
104 static __always_inline u16 vmcs_read16(unsigned long field)
105 {
106 	vmcs_check16(field);
107 	if (static_branch_unlikely(&enable_evmcs))
108 		return evmcs_read16(field);
109 	return __vmcs_readl(field);
110 }
111 
112 static __always_inline u32 vmcs_read32(unsigned long field)
113 {
114 	vmcs_check32(field);
115 	if (static_branch_unlikely(&enable_evmcs))
116 		return evmcs_read32(field);
117 	return __vmcs_readl(field);
118 }
119 
120 static __always_inline u64 vmcs_read64(unsigned long field)
121 {
122 	vmcs_check64(field);
123 	if (static_branch_unlikely(&enable_evmcs))
124 		return evmcs_read64(field);
125 #ifdef CONFIG_X86_64
126 	return __vmcs_readl(field);
127 #else
128 	return __vmcs_readl(field) | ((u64)__vmcs_readl(field+1) << 32);
129 #endif
130 }
131 
132 static __always_inline unsigned long vmcs_readl(unsigned long field)
133 {
134 	vmcs_checkl(field);
135 	if (static_branch_unlikely(&enable_evmcs))
136 		return evmcs_read64(field);
137 	return __vmcs_readl(field);
138 }
139 
140 #define vmx_asm1(insn, op1, error_args...)				\
141 do {									\
142 	asm_volatile_goto("1: " __stringify(insn) " %0\n\t"		\
143 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
144 			  "jna %l[error]\n\t"				\
145 			  _ASM_EXTABLE(1b, %l[fault])			\
146 			  : : op1 : "cc" : error, fault);		\
147 	return;								\
148 error:									\
149 	instrumentation_begin();					\
150 	insn##_error(error_args);					\
151 	instrumentation_end();						\
152 	return;								\
153 fault:									\
154 	kvm_spurious_fault();						\
155 } while (0)
156 
157 #define vmx_asm2(insn, op1, op2, error_args...)				\
158 do {									\
159 	asm_volatile_goto("1: "  __stringify(insn) " %1, %0\n\t"	\
160 			  ".byte 0x2e\n\t" /* branch not taken hint */	\
161 			  "jna %l[error]\n\t"				\
162 			  _ASM_EXTABLE(1b, %l[fault])			\
163 			  : : op1, op2 : "cc" : error, fault);		\
164 	return;								\
165 error:									\
166 	instrumentation_begin();					\
167 	insn##_error(error_args);					\
168 	instrumentation_end();						\
169 	return;								\
170 fault:									\
171 	kvm_spurious_fault();						\
172 } while (0)
173 
174 static __always_inline void __vmcs_writel(unsigned long field, unsigned long value)
175 {
176 	vmx_asm2(vmwrite, "r"(field), "rm"(value), field, value);
177 }
178 
179 static __always_inline void vmcs_write16(unsigned long field, u16 value)
180 {
181 	vmcs_check16(field);
182 	if (static_branch_unlikely(&enable_evmcs))
183 		return evmcs_write16(field, value);
184 
185 	__vmcs_writel(field, value);
186 }
187 
188 static __always_inline void vmcs_write32(unsigned long field, u32 value)
189 {
190 	vmcs_check32(field);
191 	if (static_branch_unlikely(&enable_evmcs))
192 		return evmcs_write32(field, value);
193 
194 	__vmcs_writel(field, value);
195 }
196 
197 static __always_inline void vmcs_write64(unsigned long field, u64 value)
198 {
199 	vmcs_check64(field);
200 	if (static_branch_unlikely(&enable_evmcs))
201 		return evmcs_write64(field, value);
202 
203 	__vmcs_writel(field, value);
204 #ifndef CONFIG_X86_64
205 	__vmcs_writel(field+1, value >> 32);
206 #endif
207 }
208 
209 static __always_inline void vmcs_writel(unsigned long field, unsigned long value)
210 {
211 	vmcs_checkl(field);
212 	if (static_branch_unlikely(&enable_evmcs))
213 		return evmcs_write64(field, value);
214 
215 	__vmcs_writel(field, value);
216 }
217 
218 static __always_inline void vmcs_clear_bits(unsigned long field, u32 mask)
219 {
220 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
221 			 "vmcs_clear_bits does not support 64-bit fields");
222 	if (static_branch_unlikely(&enable_evmcs))
223 		return evmcs_write32(field, evmcs_read32(field) & ~mask);
224 
225 	__vmcs_writel(field, __vmcs_readl(field) & ~mask);
226 }
227 
228 static __always_inline void vmcs_set_bits(unsigned long field, u32 mask)
229 {
230 	BUILD_BUG_ON_MSG(__builtin_constant_p(field) && ((field) & 0x6000) == 0x2000,
231 			 "vmcs_set_bits does not support 64-bit fields");
232 	if (static_branch_unlikely(&enable_evmcs))
233 		return evmcs_write32(field, evmcs_read32(field) | mask);
234 
235 	__vmcs_writel(field, __vmcs_readl(field) | mask);
236 }
237 
238 static inline void vmcs_clear(struct vmcs *vmcs)
239 {
240 	u64 phys_addr = __pa(vmcs);
241 
242 	vmx_asm1(vmclear, "m"(phys_addr), vmcs, phys_addr);
243 }
244 
245 static inline void vmcs_load(struct vmcs *vmcs)
246 {
247 	u64 phys_addr = __pa(vmcs);
248 
249 	if (static_branch_unlikely(&enable_evmcs))
250 		return evmcs_load(phys_addr);
251 
252 	vmx_asm1(vmptrld, "m"(phys_addr), vmcs, phys_addr);
253 }
254 
255 static inline void __invvpid(unsigned long ext, u16 vpid, gva_t gva)
256 {
257 	struct {
258 		u64 vpid : 16;
259 		u64 rsvd : 48;
260 		u64 gva;
261 	} operand = { vpid, 0, gva };
262 
263 	vmx_asm2(invvpid, "r"(ext), "m"(operand), ext, vpid, gva);
264 }
265 
266 static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
267 {
268 	struct {
269 		u64 eptp, gpa;
270 	} operand = {eptp, gpa};
271 
272 	vmx_asm2(invept, "r"(ext), "m"(operand), ext, eptp, gpa);
273 }
274 
275 static inline void vpid_sync_vcpu_single(int vpid)
276 {
277 	if (vpid == 0)
278 		return;
279 
280 	__invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
281 }
282 
283 static inline void vpid_sync_vcpu_global(void)
284 {
285 	__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
286 }
287 
288 static inline void vpid_sync_context(int vpid)
289 {
290 	if (cpu_has_vmx_invvpid_single())
291 		vpid_sync_vcpu_single(vpid);
292 	else if (vpid != 0)
293 		vpid_sync_vcpu_global();
294 }
295 
296 static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
297 {
298 	if (vpid == 0)
299 		return;
300 
301 	if (cpu_has_vmx_invvpid_individual_addr())
302 		__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
303 	else
304 		vpid_sync_context(vpid);
305 }
306 
307 static inline void ept_sync_global(void)
308 {
309 	__invept(VMX_EPT_EXTENT_GLOBAL, 0, 0);
310 }
311 
312 static inline void ept_sync_context(u64 eptp)
313 {
314 	if (cpu_has_vmx_invept_context())
315 		__invept(VMX_EPT_EXTENT_CONTEXT, eptp, 0);
316 	else
317 		ept_sync_global();
318 }
319 
320 #endif /* __KVM_X86_VMX_INSN_H */
321