/* SPDX-License-Identifier: GPL-2.0 */
#ifndef ARCH_X86_KVM_CPUID_H
#define ARCH_X86_KVM_CPUID_H

#include "reverse_cpuid.h"
#include <asm/cpu.h>
#include <asm/processor.h>
#include <uapi/asm/kvm_para.h>

extern u32 kvm_cpu_caps[NR_KVM_CPU_CAPS] __read_mostly;
extern bool kvm_is_configuring_cpu_caps __read_mostly;

void kvm_initialize_cpu_caps(void);

static inline void kvm_finalize_cpu_caps(void)
{
        WARN_ON_ONCE(!kvm_is_configuring_cpu_caps);
        kvm_is_configuring_cpu_caps = false;
}

void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu);
struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2(struct kvm_cpuid_entry2 *entries,
                                               int nent, u32 function, u64 index);
/*
 * Magic value used by KVM when querying userspace-provided CPUID entries and
 * doesn't care about the CPIUD index because the index of the function in
 * question is not significant.  Note, this magic value must have at least one
 * bit set in bits[63:32] and must be consumed as a u64 by kvm_find_cpuid_entry2()
 * to avoid false positives when processing guest CPUID input.
 *
 * KVM_CPUID_INDEX_NOT_SIGNIFICANT should never be used directly outside of
 * kvm_find_cpuid_entry2() and kvm_find_cpuid_entry().
 */
#define KVM_CPUID_INDEX_NOT_SIGNIFICANT -1ull

static inline struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
                                                                  u32 function, u32 index)
{
        return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
                                     function, index);
}

static inline struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
                                                            u32 function)
{
        return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
                                     function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
}

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);

void __init kvm_init_xstate_sizes(void);
u32 xstate_required_size(u64 xstate_bv, bool compacted);

int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu);
int cpuid_query_maxguestphyaddr(struct kvm_vcpu *vcpu);
u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu);

static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
{
        return vcpu->arch.maxphyaddr;
}

static inline bool kvm_vcpu_is_legal_gpa(struct kvm_vcpu *vcpu, gpa_t gpa)
{
        return !(gpa & vcpu->arch.reserved_gpa_bits);
}

static inline bool kvm_vcpu_is_legal_aligned_gpa(struct kvm_vcpu *vcpu,
                                                 gpa_t gpa, gpa_t alignment)
{
        return IS_ALIGNED(gpa, alignment) && kvm_vcpu_is_legal_gpa(vcpu, gpa);
}

static inline bool page_address_valid(struct kvm_vcpu *vcpu, gpa_t gpa)
{
        return kvm_vcpu_is_legal_aligned_gpa(vcpu, gpa, PAGE_SIZE);
}

static __always_inline void cpuid_entry_override(struct kvm_cpuid_entry2 *entry,
                                                 unsigned int 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 bool guest_cpuid_has(struct kvm_vcpu *vcpu,
                                            unsigned int x86_feature)
{
        const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature);
        struct kvm_cpuid_entry2 *entry;
        u32 *reg;

        /*
         * XSAVES is a special snowflake.  Due to lack of a dedicated intercept
         * on SVM, KVM must assume that XSAVES (and thus XRSTORS) is usable by
         * the guest if the host supports XSAVES and *XSAVE* is exposed to the
         * guest.  Because the guest can execute XSAVES and XRSTORS, i.e. can
         * indirectly consume XSS, KVM must ensure XSS is zeroed when running
         * the guest, i.e. must set XSAVES in vCPU capabilities.  But to reject
         * direct XSS reads and writes (to minimize the virtualization hole and
         * honor userspace's CPUID), KVM needs to check the raw guest CPUID,
         * not KVM's view of guest capabilities.
         *
         * For all other features, guest capabilities are accurate.  Expand
         * this allowlist with extreme vigilance.
         */
        BUILD_BUG_ON(x86_feature != X86_FEATURE_XSAVES);

        entry = kvm_find_cpuid_entry_index(vcpu, cpuid.function, cpuid.index);
        if (!entry)
                return NULL;

        reg = __cpuid_entry_get_reg(entry, cpuid.reg);
        if (!reg)
                return false;

        return *reg & __feature_bit(x86_feature);
}

static inline bool guest_cpuid_is_amd_compatible(struct kvm_vcpu *vcpu)
{
        return vcpu->arch.is_amd_compatible;
}

static inline bool guest_cpuid_is_intel_compatible(struct kvm_vcpu *vcpu)
{
        return !guest_cpuid_is_amd_compatible(vcpu);
}

static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
{
        struct kvm_cpuid_entry2 *best;

        best = kvm_find_cpuid_entry(vcpu, 0x1);
        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);
        if (!best)
                return -1;

        return x86_model(best->eax);
}

static inline bool cpuid_model_is_consistent(struct kvm_vcpu *vcpu)
{
        return boot_cpu_data.x86_model == guest_cpuid_model(vcpu);
}

static inline int guest_cpuid_stepping(struct kvm_vcpu *vcpu)
{
        struct kvm_cpuid_entry2 *best;

        best = kvm_find_cpuid_entry(vcpu, 0x1);
        if (!best)
                return -1;

        return x86_stepping(best->eax);
}

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 = __feature_leaf(x86_feature);

        WARN_ON_ONCE(!kvm_is_configuring_cpu_caps);
        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 = __feature_leaf(x86_feature);

        WARN_ON_ONCE(!kvm_is_configuring_cpu_caps);
        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 = __feature_leaf(x86_feature);

        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 __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);
}

static __always_inline void guest_cpu_cap_set(struct kvm_vcpu *vcpu,
                                              unsigned int x86_feature)
{
        unsigned int x86_leaf = __feature_leaf(x86_feature);

        vcpu->arch.cpu_caps[x86_leaf] |= __feature_bit(x86_feature);
}

static __always_inline void guest_cpu_cap_clear(struct kvm_vcpu *vcpu,
                                                unsigned int x86_feature)
{
        unsigned int x86_leaf = __feature_leaf(x86_feature);

        vcpu->arch.cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature);
}

static __always_inline void guest_cpu_cap_change(struct kvm_vcpu *vcpu,
                                                 unsigned int x86_feature,
                                                 bool guest_has_cap)
{
        if (guest_has_cap)
                guest_cpu_cap_set(vcpu, x86_feature);
        else
                guest_cpu_cap_clear(vcpu, x86_feature);
}

static __always_inline bool guest_cpu_cap_has(struct kvm_vcpu *vcpu,
                                              unsigned int x86_feature)
{
        unsigned int x86_leaf = __feature_leaf(x86_feature);

        /*
         * Except for MWAIT, querying dynamic feature bits is disallowed, so
         * that KVM can defer runtime updates until the next CPUID emulation.
         */
        BUILD_BUG_ON(x86_feature == X86_FEATURE_APIC ||
                     x86_feature == X86_FEATURE_OSXSAVE ||
                     x86_feature == X86_FEATURE_OSPKE);

        return vcpu->arch.cpu_caps[x86_leaf] & __feature_bit(x86_feature);
}

static inline bool kvm_vcpu_is_legal_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
{
        if (guest_cpu_cap_has(vcpu, X86_FEATURE_LAM))
                cr3 &= ~(X86_CR3_LAM_U48 | X86_CR3_LAM_U57);

        return kvm_vcpu_is_legal_gpa(vcpu, cr3);
}

static inline bool guest_has_spec_ctrl_msr(struct kvm_vcpu *vcpu)
{
        return (guest_cpu_cap_has(vcpu, X86_FEATURE_SPEC_CTRL) ||
                guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_STIBP) ||
                guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_IBRS) ||
                guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_SSBD));
}

static inline bool guest_has_pred_cmd_msr(struct kvm_vcpu *vcpu)
{
        return (guest_cpu_cap_has(vcpu, X86_FEATURE_SPEC_CTRL) ||
                guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_IBPB) ||
                guest_cpu_cap_has(vcpu, X86_FEATURE_SBPB));
}

#endif