KVM: x86: generalize guest_cpuid_has_ helpers

This patch turns guest_cpuid_has_XYZ(cpuid) into guest_cpuid_has(cpuid,
X86_FEATURE_XYZ), which gets rid of many very similar helpers.

When seeing a X86_FEATURE_*, we can know which cpuid it belongs to, but
this information isn't in common code, so we recreate it for KVM.

Add some BUILD_BUG_ONs to make sure that it runs nicely.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 57 insertions, 113 deletions

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index c723d646..4e9ac93 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -3,6 +3,7 @@
 
 #include "x86.h"
 #include <asm/cpu.h>
+#include <asm/processor.h>
 
 int kvm_update_cpuid(struct kvm_vcpu *vcpu);
 bool kvm_mpx_supported(void);
@@ -29,95 +30,78 @@ static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
 	return vcpu->arch.maxphyaddr;
 }
 
-static inline bool guest_cpuid_has_xsave(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
+struct cpuid_reg {
+	u32 function;
+	u32 index;
+	int reg;
+};
 
-	if (!static_cpu_has(X86_FEATURE_XSAVE))
-		return false;
-
-	best = kvm_find_cpuid_entry(vcpu, 1, 0);
-	return best && (best->ecx & bit(X86_FEATURE_XSAVE));
-}
+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] = {0xc0000001, 0, CPUID_ECX},
+	[CPUID_7_0_EBX]       = {         7, 0, CPUID_EBX},
+	[CPUID_D_1_EAX]       = {       0xd, 1, CPUID_EAX},
+	[CPUID_F_0_EDX]       = {       0xf, 0, CPUID_EDX},
+	[CPUID_F_1_EDX]       = {       0xf, 1, CPUID_EDX},
+	[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},
+};
 
-static inline bool guest_cpuid_has_mtrr(struct kvm_vcpu *vcpu)
+static __always_inline struct cpuid_reg x86_feature_cpuid(unsigned x86_feature)
 {
-	struct kvm_cpuid_entry2 *best;
+	unsigned x86_leaf = x86_feature / 32;
 
-	best = kvm_find_cpuid_entry(vcpu, 1, 0);
-	return best && (best->edx & bit(X86_FEATURE_MTRR));
-}
+	BUILD_BUG_ON(!__builtin_constant_p(x86_leaf));
+	BUILD_BUG_ON(x86_leaf >= ARRAY_SIZE(reverse_cpuid));
+	BUILD_BUG_ON(reverse_cpuid[x86_leaf].function == 0);
 
-static inline bool guest_cpuid_has_tsc_adjust(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_TSC_ADJUST));
-}
-
-static inline bool guest_cpuid_has_smep(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_SMEP));
+	return reverse_cpuid[x86_leaf];
 }
 
-static inline bool guest_cpuid_has_smap(struct kvm_vcpu *vcpu)
+static __always_inline int *guest_cpuid_get_register(struct kvm_vcpu *vcpu, unsigned x86_feature)
 {
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_SMAP));
-}
-
-static inline bool guest_cpuid_has_fsgsbase(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_FSGSBASE));
-}
-
-static inline bool guest_cpuid_has_pku(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ecx & bit(X86_FEATURE_PKU));
-}
-
-static inline bool guest_cpuid_has_longmode(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
-	return best && (best->edx & bit(X86_FEATURE_LM));
-}
+	struct kvm_cpuid_entry2 *entry;
+	const struct cpuid_reg cpuid = x86_feature_cpuid(x86_feature);
 
-static inline bool guest_cpuid_has_osvw(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
+	entry = kvm_find_cpuid_entry(vcpu, cpuid.function, cpuid.index);
+	if (!entry)
+		return NULL;
 
-	best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
-	return best && (best->ecx & bit(X86_FEATURE_OSVW));
+	switch (cpuid.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 inline bool guest_cpuid_has_pcid(struct kvm_vcpu *vcpu)
+static __always_inline bool guest_cpuid_has(struct kvm_vcpu *vcpu, unsigned x86_feature)
 {
-	struct kvm_cpuid_entry2 *best;
+	int *reg;
 
-	best = kvm_find_cpuid_entry(vcpu, 1, 0);
-	return best && (best->ecx & bit(X86_FEATURE_PCID));
-}
+	if (x86_feature == X86_FEATURE_XSAVE &&
+			!static_cpu_has(X86_FEATURE_XSAVE))
+		return false;
 
-static inline bool guest_cpuid_has_x2apic(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
+	reg = guest_cpuid_get_register(vcpu, x86_feature);
+	if (!reg)
+		return false;
 
-	best = kvm_find_cpuid_entry(vcpu, 1, 0);
-	return best && (best->ecx & bit(X86_FEATURE_X2APIC));
+	return *reg & bit(x86_feature);
 }
 
 static inline bool guest_cpuid_is_amd(struct kvm_vcpu *vcpu)
@@ -128,46 +112,6 @@ static inline bool guest_cpuid_is_amd(struct kvm_vcpu *vcpu)
 	return best && best->ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx;
 }
 
-static inline bool guest_cpuid_has_gbpages(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
-	return best && (best->edx & bit(X86_FEATURE_GBPAGES));
-}
-
-static inline bool guest_cpuid_has_rtm(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_RTM));
-}
-
-static inline bool guest_cpuid_has_mpx(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 7, 0);
-	return best && (best->ebx & bit(X86_FEATURE_MPX));
-}
-
-static inline bool guest_cpuid_has_rdtscp(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0);
-	return best && (best->edx & bit(X86_FEATURE_RDTSCP));
-}
-
-static inline bool guest_cpuid_has_nrips(struct kvm_vcpu *vcpu)
-{
-	struct kvm_cpuid_entry2 *best;
-
-	best = kvm_find_cpuid_entry(vcpu, 0x8000000a, 0);
-	return best && (best->edx & bit(X86_FEATURE_NRIPS));
-}
-
 static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best;