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-rw-r--r--arch/x86/kvm/cpuid.h342
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