1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef ARCH_X86_KVM_CPUID_H
3 #define ARCH_X86_KVM_CPUID_H
4
5 #include "x86.h"
6 #include <asm/cpu.h>
7 #include <asm/processor.h>
8 #include <uapi/asm/kvm_para.h>
9
10 extern u32 kvm_cpu_caps[NCAPINTS] __read_mostly;
11 void kvm_set_cpu_caps(void);
12
13 void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
14 void kvm_update_pv_runtime(struct kvm_vcpu *vcpu);
15 struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
16 u32 function, u32 index);
17 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
18 struct kvm_cpuid_entry2 __user *entries,
19 unsigned int type);
20 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
21 struct kvm_cpuid *cpuid,
22 struct kvm_cpuid_entry __user *entries);
23 int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
24 struct kvm_cpuid2 *cpuid,
25 struct kvm_cpuid_entry2 __user *entries);
26 int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
27 struct kvm_cpuid2 *cpuid,
28 struct kvm_cpuid_entry2 __user *entries);
29 bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
30 u32 *ecx, u32 *edx, bool exact_only);
31
32 int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu);
33
cpuid_maxphyaddr(struct kvm_vcpu * vcpu)34 static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
35 {
36 return vcpu->arch.maxphyaddr;
37 }
38
kvm_vcpu_is_illegal_gpa(struct kvm_vcpu * vcpu,gpa_t gpa)39 static inline bool kvm_vcpu_is_illegal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
40 {
41 return (gpa >= BIT_ULL(cpuid_maxphyaddr(vcpu)));
42 }
43
44 struct cpuid_reg {
45 u32 function;
46 u32 index;
47 int reg;
48 };
49
50 static const struct cpuid_reg reverse_cpuid[] = {
51 [CPUID_1_EDX] = { 1, 0, CPUID_EDX},
52 [CPUID_8000_0001_EDX] = {0x80000001, 0, CPUID_EDX},
53 [CPUID_8086_0001_EDX] = {0x80860001, 0, CPUID_EDX},
54 [CPUID_1_ECX] = { 1, 0, CPUID_ECX},
55 [CPUID_C000_0001_EDX] = {0xc0000001, 0, CPUID_EDX},
56 [CPUID_8000_0001_ECX] = {0x80000001, 0, CPUID_ECX},
57 [CPUID_7_0_EBX] = { 7, 0, CPUID_EBX},
58 [CPUID_D_1_EAX] = { 0xd, 1, CPUID_EAX},
59 [CPUID_8000_0008_EBX] = {0x80000008, 0, CPUID_EBX},
60 [CPUID_6_EAX] = { 6, 0, CPUID_EAX},
61 [CPUID_8000_000A_EDX] = {0x8000000a, 0, CPUID_EDX},
62 [CPUID_7_ECX] = { 7, 0, CPUID_ECX},
63 [CPUID_8000_0007_EBX] = {0x80000007, 0, CPUID_EBX},
64 [CPUID_7_EDX] = { 7, 0, CPUID_EDX},
65 [CPUID_7_1_EAX] = { 7, 1, CPUID_EAX},
66 [CPUID_8000_0021_EAX] = {0x80000021, 0, CPUID_EAX},
67 };
68
69 /*
70 * Reverse CPUID and its derivatives can only be used for hardware-defined
71 * feature words, i.e. words whose bits directly correspond to a CPUID leaf.
72 * Retrieving a feature bit or masking guest CPUID from a Linux-defined word
73 * is nonsensical as the bit number/mask is an arbitrary software-defined value
74 * and can't be used by KVM to query/control guest capabilities. And obviously
75 * the leaf being queried must have an entry in the lookup table.
76 */
reverse_cpuid_check(unsigned int x86_leaf)77 static __always_inline void reverse_cpuid_check(unsigned int x86_leaf)
78 {
79 BUILD_BUG_ON(x86_leaf == CPUID_LNX_1);
80 BUILD_BUG_ON(x86_leaf == CPUID_LNX_2);
81 BUILD_BUG_ON(x86_leaf == CPUID_LNX_3);
82 BUILD_BUG_ON(x86_leaf == CPUID_LNX_4);
83 BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid));
84 BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0);
85 }
86
87 /*
88 * Retrieve the bit mask from an X86_FEATURE_* definition. Features contain
89 * the hardware defined bit number (stored in bits 4:0) and a software defined
90 * "word" (stored in bits 31:5). The word is used to index into arrays of
91 * bit masks that hold the per-cpu feature capabilities, e.g. this_cpu_has().
92 */
__feature_bit(int x86_feature)93 static __always_inline u32 __feature_bit(int x86_feature)
94 {
95 reverse_cpuid_check(x86_feature / 32);
96 return 1 << (x86_feature & 31);
97 }
98
99 #define feature_bit(name) __feature_bit(X86_FEATURE_##name)
100
x86_feature_cpuid(unsigned int x86_feature)101 static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned int x86_feature)
102 {
103 unsigned int x86_leaf = x86_feature / 32;
104
105 reverse_cpuid_check(x86_leaf);
106 return reverse_cpuid[x86_leaf];
107 }
108
__cpuid_entry_get_reg(struct kvm_cpuid_entry2 * entry,u32 reg)109 static __always_inline u32 *__cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry,
110 u32 reg)
111 {
112 switch (reg) {
113 case CPUID_EAX:
114 return &entry->eax;
115 case CPUID_EBX:
116 return &entry->ebx;
117 case CPUID_ECX:
118 return &entry->ecx;
119 case CPUID_EDX:
120 return &entry->edx;
121 default:
122 BUILD_BUG();
123 return NULL;
124 }
125 }
126
cpuid_entry_get_reg(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature)127 static __always_inline u32 *cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry,
128 unsigned int x86_feature)
129 {
130 const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature);
131
132 return __cpuid_entry_get_reg(entry, cpuid.reg);
133 }
134
cpuid_entry_get(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature)135 static __always_inline u32 cpuid_entry_get(struct kvm_cpuid_entry2 *entry,
136 unsigned int x86_feature)
137 {
138 u32 *reg = cpuid_entry_get_reg(entry, x86_feature);
139
140 return *reg & __feature_bit(x86_feature);
141 }
142
cpuid_entry_has(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature)143 static __always_inline bool cpuid_entry_has(struct kvm_cpuid_entry2 *entry,
144 unsigned int x86_feature)
145 {
146 return cpuid_entry_get(entry, x86_feature);
147 }
148
cpuid_entry_clear(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature)149 static __always_inline void cpuid_entry_clear(struct kvm_cpuid_entry2 *entry,
150 unsigned int x86_feature)
151 {
152 u32 *reg = cpuid_entry_get_reg(entry, x86_feature);
153
154 *reg &= ~__feature_bit(x86_feature);
155 }
156
cpuid_entry_set(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature)157 static __always_inline void cpuid_entry_set(struct kvm_cpuid_entry2 *entry,
158 unsigned int x86_feature)
159 {
160 u32 *reg = cpuid_entry_get_reg(entry, x86_feature);
161
162 *reg |= __feature_bit(x86_feature);
163 }
164
cpuid_entry_change(struct kvm_cpuid_entry2 * entry,unsigned int x86_feature,bool set)165 static __always_inline void cpuid_entry_change(struct kvm_cpuid_entry2 *entry,
166 unsigned int x86_feature,
167 bool set)
168 {
169 u32 *reg = cpuid_entry_get_reg(entry, x86_feature);
170
171 /*
172 * Open coded instead of using cpuid_entry_{clear,set}() to coerce the
173 * compiler into using CMOV instead of Jcc when possible.
174 */
175 if (set)
176 *reg |= __feature_bit(x86_feature);
177 else
178 *reg &= ~__feature_bit(x86_feature);
179 }
180
cpuid_entry_override(struct kvm_cpuid_entry2 * entry,enum cpuid_leafs leaf)181 static __always_inline void cpuid_entry_override(struct kvm_cpuid_entry2 *entry,
182 enum cpuid_leafs leaf)
183 {
184 u32 *reg = cpuid_entry_get_reg(entry, leaf * 32);
185
186 BUILD_BUG_ON(leaf >= ARRAY_SIZE(kvm_cpu_caps));
187 *reg = kvm_cpu_caps[leaf];
188 }
189
guest_cpuid_get_register(struct kvm_vcpu * vcpu,unsigned int x86_feature)190 static __always_inline u32 *guest_cpuid_get_register(struct kvm_vcpu *vcpu,
191 unsigned int x86_feature)
192 {
193 const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature);
194 struct kvm_cpuid_entry2 *entry;
195
196 entry = kvm_find_cpuid_entry(vcpu, cpuid.function, cpuid.index);
197 if (!entry)
198 return NULL;
199
200 return __cpuid_entry_get_reg(entry, cpuid.reg);
201 }
202
guest_cpuid_has(struct kvm_vcpu * vcpu,unsigned int x86_feature)203 static __always_inline bool guest_cpuid_has(struct kvm_vcpu *vcpu,
204 unsigned int x86_feature)
205 {
206 u32 *reg;
207
208 reg = guest_cpuid_get_register(vcpu, x86_feature);
209 if (!reg)
210 return false;
211
212 return *reg & __feature_bit(x86_feature);
213 }
214
guest_cpuid_clear(struct kvm_vcpu * vcpu,unsigned int x86_feature)215 static __always_inline void guest_cpuid_clear(struct kvm_vcpu *vcpu,
216 unsigned int x86_feature)
217 {
218 u32 *reg;
219
220 reg = guest_cpuid_get_register(vcpu, x86_feature);
221 if (reg)
222 *reg &= ~__feature_bit(x86_feature);
223 }
224
guest_cpuid_is_amd_or_hygon(struct kvm_vcpu * vcpu)225 static inline bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu)
226 {
227 struct kvm_cpuid_entry2 *best;
228
229 best = kvm_find_cpuid_entry(vcpu, 0, 0);
230 return best &&
231 (is_guest_vendor_amd(best->ebx, best->ecx, best->edx) ||
232 is_guest_vendor_hygon(best->ebx, best->ecx, best->edx));
233 }
234
guest_cpuid_family(struct kvm_vcpu * vcpu)235 static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
236 {
237 struct kvm_cpuid_entry2 *best;
238
239 best = kvm_find_cpuid_entry(vcpu, 0x1, 0);
240 if (!best)
241 return -1;
242
243 return x86_family(best->eax);
244 }
245
guest_cpuid_model(struct kvm_vcpu * vcpu)246 static inline int guest_cpuid_model(struct kvm_vcpu *vcpu)
247 {
248 struct kvm_cpuid_entry2 *best;
249
250 best = kvm_find_cpuid_entry(vcpu, 0x1, 0);
251 if (!best)
252 return -1;
253
254 return x86_model(best->eax);
255 }
256
guest_cpuid_stepping(struct kvm_vcpu * vcpu)257 static inline int guest_cpuid_stepping(struct kvm_vcpu *vcpu)
258 {
259 struct kvm_cpuid_entry2 *best;
260
261 best = kvm_find_cpuid_entry(vcpu, 0x1, 0);
262 if (!best)
263 return -1;
264
265 return x86_stepping(best->eax);
266 }
267
guest_has_spec_ctrl_msr(struct kvm_vcpu * vcpu)268 static inline bool guest_has_spec_ctrl_msr(struct kvm_vcpu *vcpu)
269 {
270 return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) ||
271 guest_cpuid_has(vcpu, X86_FEATURE_AMD_STIBP) ||
272 guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBRS) ||
273 guest_cpuid_has(vcpu, X86_FEATURE_AMD_SSBD));
274 }
275
guest_has_pred_cmd_msr(struct kvm_vcpu * vcpu)276 static inline bool guest_has_pred_cmd_msr(struct kvm_vcpu *vcpu)
277 {
278 return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) ||
279 guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBPB));
280 }
281
supports_cpuid_fault(struct kvm_vcpu * vcpu)282 static inline bool supports_cpuid_fault(struct kvm_vcpu *vcpu)
283 {
284 return vcpu->arch.msr_platform_info & MSR_PLATFORM_INFO_CPUID_FAULT;
285 }
286
cpuid_fault_enabled(struct kvm_vcpu * vcpu)287 static inline bool cpuid_fault_enabled(struct kvm_vcpu *vcpu)
288 {
289 return vcpu->arch.msr_misc_features_enables &
290 MSR_MISC_FEATURES_ENABLES_CPUID_FAULT;
291 }
292
kvm_cpu_cap_clear(unsigned int x86_feature)293 static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature)
294 {
295 unsigned int x86_leaf = x86_feature / 32;
296
297 reverse_cpuid_check(x86_leaf);
298 kvm_cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature);
299 }
300
kvm_cpu_cap_set(unsigned int x86_feature)301 static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature)
302 {
303 unsigned int x86_leaf = x86_feature / 32;
304
305 reverse_cpuid_check(x86_leaf);
306 kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature);
307 }
308
kvm_cpu_cap_get(unsigned int x86_feature)309 static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature)
310 {
311 unsigned int x86_leaf = x86_feature / 32;
312
313 reverse_cpuid_check(x86_leaf);
314 return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature);
315 }
316
kvm_cpu_cap_has(unsigned int x86_feature)317 static __always_inline bool kvm_cpu_cap_has(unsigned int x86_feature)
318 {
319 return !!kvm_cpu_cap_get(x86_feature);
320 }
321
kvm_cpu_cap_check_and_set(unsigned int x86_feature)322 static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature)
323 {
324 if (boot_cpu_has(x86_feature))
325 kvm_cpu_cap_set(x86_feature);
326 }
327
page_address_valid(struct kvm_vcpu * vcpu,gpa_t gpa)328 static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa)
329 {
330 return PAGE_ALIGNED(gpa) && !(gpa >> cpuid_maxphyaddr(vcpu));
331 }
332
guest_pv_has(struct kvm_vcpu * vcpu,unsigned int kvm_feature)333 static __always_inline bool guest_pv_has(struct kvm_vcpu *vcpu,
334 unsigned int kvm_feature)
335 {
336 if (!vcpu->arch.pv_cpuid.enforce)
337 return true;
338
339 return vcpu->arch.pv_cpuid.features & (1u << kvm_feature);
340 }
341
342 #endif
343