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