diff options
Diffstat (limited to 'arch/x86/kvm/cpuid.h')
| -rw-r--r-- | arch/x86/kvm/cpuid.h | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h new file mode 100644 index 000000000..1ba9313d2 --- /dev/null +++ b/arch/x86/kvm/cpuid.h @@ -0,0 +1,342 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef ARCH_X86_KVM_CPUID_H +#define ARCH_X86_KVM_CPUID_H + +#include "x86.h" +#include <asm/cpu.h> +#include <asm/processor.h> +#include <uapi/asm/kvm_para.h> + +extern u32 kvm_cpu_caps[NCAPINTS] __read_mostly; +void kvm_set_cpu_caps(void); + +void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu); +void kvm_update_pv_runtime(struct kvm_vcpu *vcpu); +struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, + u32 function, u32 index); +int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid, + struct kvm_cpuid_entry2 __user *entries, + unsigned int type); +int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, + struct kvm_cpuid *cpuid, + struct kvm_cpuid_entry __user *entries); +int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, + struct kvm_cpuid2 *cpuid, + struct kvm_cpuid_entry2 __user *entries); +int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, + struct kvm_cpuid2 *cpuid, + struct kvm_cpuid_entry2 __user *entries); +bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, + u32 *ecx, u32 *edx, bool exact_only); + +int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu); + +static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.maxphyaddr; +} + +static inline bool kvm_vcpu_is_illegal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa) +{ + return (gpa >= BIT_ULL(cpuid_maxphyaddr(vcpu))); +} + +struct cpuid_reg { + u32 function; + u32 index; + int reg; +}; + +static const struct cpuid_reg reverse_cpuid[] = { + [CPUID_1_EDX] = { 1, 0, CPUID_EDX}, + [CPUID_8000_0001_EDX] = {0x80000001, 0, CPUID_EDX}, + [CPUID_8086_0001_EDX] = {0x80860001, 0, CPUID_EDX}, + [CPUID_1_ECX] = { 1, 0, CPUID_ECX}, + [CPUID_C000_0001_EDX] = {0xc0000001, 0, CPUID_EDX}, + [CPUID_8000_0001_ECX] = {0x80000001, 0, CPUID_ECX}, + [CPUID_7_0_EBX] = { 7, 0, CPUID_EBX}, + [CPUID_D_1_EAX] = { 0xd, 1, CPUID_EAX}, + [CPUID_8000_0008_EBX] = {0x80000008, 0, CPUID_EBX}, + [CPUID_6_EAX] = { 6, 0, CPUID_EAX}, + [CPUID_8000_000A_EDX] = {0x8000000a, 0, CPUID_EDX}, + [CPUID_7_ECX] = { 7, 0, CPUID_ECX}, + [CPUID_8000_0007_EBX] = {0x80000007, 0, CPUID_EBX}, + [CPUID_7_EDX] = { 7, 0, CPUID_EDX}, + [CPUID_7_1_EAX] = { 7, 1, CPUID_EAX}, + [CPUID_8000_0021_EAX] = {0x80000021, 0, CPUID_EAX}, +}; + +/* + * Reverse CPUID and its derivatives can only be used for hardware-defined + * feature words, i.e. words whose bits directly correspond to a CPUID leaf. + * Retrieving a feature bit or masking guest CPUID from a Linux-defined word + * is nonsensical as the bit number/mask is an arbitrary software-defined value + * and can't be used by KVM to query/control guest capabilities. And obviously + * the leaf being queried must have an entry in the lookup table. + */ +static __always_inline void reverse_cpuid_check(unsigned int x86_leaf) +{ + BUILD_BUG_ON(x86_leaf == CPUID_LNX_1); + BUILD_BUG_ON(x86_leaf == CPUID_LNX_2); + BUILD_BUG_ON(x86_leaf == CPUID_LNX_3); + BUILD_BUG_ON(x86_leaf == CPUID_LNX_4); + BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid)); + BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0); +} + +/* + * Retrieve the bit mask from an X86_FEATURE_* definition. Features contain + * the hardware defined bit number (stored in bits 4:0) and a software defined + * "word" (stored in bits 31:5). The word is used to index into arrays of + * bit masks that hold the per-cpu feature capabilities, e.g. this_cpu_has(). + */ +static __always_inline u32 __feature_bit(int x86_feature) +{ + reverse_cpuid_check(x86_feature / 32); + return 1 << (x86_feature & 31); +} + +#define feature_bit(name) __feature_bit(X86_FEATURE_##name) + +static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned int x86_feature) +{ + unsigned int x86_leaf = x86_feature / 32; + + reverse_cpuid_check(x86_leaf); + return reverse_cpuid[x86_leaf]; +} + +static __always_inline u32 *__cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry, + u32 reg) +{ + switch (reg) { + case CPUID_EAX: + return &entry->eax; + case CPUID_EBX: + return &entry->ebx; + case CPUID_ECX: + return &entry->ecx; + case CPUID_EDX: + return &entry->edx; + default: + BUILD_BUG(); + return NULL; + } +} + +static __always_inline u32 *cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature) +{ + const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature); + + return __cpuid_entry_get_reg(entry, cpuid.reg); +} + +static __always_inline u32 cpuid_entry_get(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature) +{ + u32 *reg = cpuid_entry_get_reg(entry, x86_feature); + + return *reg & __feature_bit(x86_feature); +} + +static __always_inline bool cpuid_entry_has(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature) +{ + return cpuid_entry_get(entry, x86_feature); +} + +static __always_inline void cpuid_entry_clear(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature) +{ + u32 *reg = cpuid_entry_get_reg(entry, x86_feature); + + *reg &= ~__feature_bit(x86_feature); +} + +static __always_inline void cpuid_entry_set(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature) +{ + u32 *reg = cpuid_entry_get_reg(entry, x86_feature); + + *reg |= __feature_bit(x86_feature); +} + +static __always_inline void cpuid_entry_change(struct kvm_cpuid_entry2 *entry, + unsigned int x86_feature, + bool set) +{ + u32 *reg = cpuid_entry_get_reg(entry, x86_feature); + + /* + * Open coded instead of using cpuid_entry_{clear,set}() to coerce the + * compiler into using CMOV instead of Jcc when possible. + */ + if (set) + *reg |= __feature_bit(x86_feature); + else + *reg &= ~__feature_bit(x86_feature); +} + +static __always_inline void cpuid_entry_override(struct kvm_cpuid_entry2 *entry, + enum cpuid_leafs leaf) +{ + u32 *reg = cpuid_entry_get_reg(entry, leaf * 32); + + BUILD_BUG_ON(leaf >= ARRAY_SIZE(kvm_cpu_caps)); + *reg = kvm_cpu_caps[leaf]; +} + +static __always_inline u32 *guest_cpuid_get_register(struct kvm_vcpu *vcpu, + unsigned int x86_feature) +{ + const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature); + struct kvm_cpuid_entry2 *entry; + + entry = kvm_find_cpuid_entry(vcpu, cpuid.function, cpuid.index); + if (!entry) + return NULL; + + return __cpuid_entry_get_reg(entry, cpuid.reg); +} + +static __always_inline bool guest_cpuid_has(struct kvm_vcpu *vcpu, + unsigned int x86_feature) +{ + u32 *reg; + + reg = guest_cpuid_get_register(vcpu, x86_feature); + if (!reg) + return false; + + return *reg & __feature_bit(x86_feature); +} + +static __always_inline void guest_cpuid_clear(struct kvm_vcpu *vcpu, + unsigned int x86_feature) +{ + u32 *reg; + + reg = guest_cpuid_get_register(vcpu, x86_feature); + if (reg) + *reg &= ~__feature_bit(x86_feature); +} + +static inline bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0, 0); + return best && + (is_guest_vendor_amd(best->ebx, best->ecx, best->edx) || + is_guest_vendor_hygon(best->ebx, best->ecx, best->edx)); +} + +static inline int guest_cpuid_family(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0x1, 0); + if (!best) + return -1; + + return x86_family(best->eax); +} + +static inline int guest_cpuid_model(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0x1, 0); + if (!best) + return -1; + + return x86_model(best->eax); +} + +static inline int guest_cpuid_stepping(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0x1, 0); + if (!best) + return -1; + + return x86_stepping(best->eax); +} + +static inline bool guest_has_spec_ctrl_msr(struct kvm_vcpu *vcpu) +{ + return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) || + guest_cpuid_has(vcpu, X86_FEATURE_AMD_STIBP) || + guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBRS) || + guest_cpuid_has(vcpu, X86_FEATURE_AMD_SSBD)); +} + +static inline bool guest_has_pred_cmd_msr(struct kvm_vcpu *vcpu) +{ + return (guest_cpuid_has(vcpu, X86_FEATURE_SPEC_CTRL) || + guest_cpuid_has(vcpu, X86_FEATURE_AMD_IBPB)); +} + +static inline bool supports_cpuid_fault(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.msr_platform_info & MSR_PLATFORM_INFO_CPUID_FAULT; +} + +static inline bool cpuid_fault_enabled(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.msr_misc_features_enables & + MSR_MISC_FEATURES_ENABLES_CPUID_FAULT; +} + +static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature) +{ + unsigned int x86_leaf = x86_feature / 32; + + reverse_cpuid_check(x86_leaf); + kvm_cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature); +} + +static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature) +{ + unsigned int x86_leaf = x86_feature / 32; + + reverse_cpuid_check(x86_leaf); + kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature); +} + +static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature) +{ + unsigned int x86_leaf = x86_feature / 32; + + reverse_cpuid_check(x86_leaf); + return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature); +} + +static __always_inline bool kvm_cpu_cap_has(unsigned int x86_feature) +{ + return !!kvm_cpu_cap_get(x86_feature); +} + +static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature) +{ + if (boot_cpu_has(x86_feature)) + kvm_cpu_cap_set(x86_feature); +} + +static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa) +{ + return PAGE_ALIGNED(gpa) && !(gpa >> cpuid_maxphyaddr(vcpu)); +} + +static __always_inline bool guest_pv_has(struct kvm_vcpu *vcpu, + unsigned int kvm_feature) +{ + if (!vcpu->arch.pv_cpuid.enforce) + return true; + + return vcpu->arch.pv_cpuid.features & (1u << kvm_feature); +} + +#endif |