[RFC PATCH 12/14] KVM: x86: Move VMX and SVM support checks into VAC

[Anish Ghulati]

kvm_is_***_supported checks to see if VMX and SVM are supported on the
host. Move this to VAC because it needs to be called before each h/w
enable and disable call.

Signed-off-by: Anish Ghulati <aghulati@xxxxxxxxxx>
---
 arch/x86/kvm/svm/svm.c | 45 +-----------------------------------------
 arch/x86/kvm/svm/vac.c | 43 ++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/vac.h     |  4 ++++
 arch/x86/kvm/vmx/vac.c | 29 +++++++++++++++++++++++++++
 arch/x86/kvm/vmx/vmx.c | 31 +----------------------------
 arch/x86/kvm/x86.h     |  6 ------
 6 files changed, 78 insertions(+), 80 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 752f769c0333..df5673c98e7b 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -515,52 +515,9 @@ static void svm_init_osvw(struct kvm_vcpu *vcpu)
 		vcpu->arch.osvw.status |= 1;
 }
 
-static bool __kvm_is_svm_supported(void)
-{
-	int cpu = smp_processor_id();
-	struct cpuinfo_x86 *c = &cpu_data(cpu);
-
-	u64 vm_cr;
-
-	if (c->x86_vendor != X86_VENDOR_AMD &&
-	    c->x86_vendor != X86_VENDOR_HYGON) {
-		pr_err("CPU %d isn't AMD or Hygon\n", cpu);
-		return false;
-	}
-
-	if (!cpu_has(c, X86_FEATURE_SVM)) {
-		pr_err("SVM not supported by CPU %d\n", cpu);
-		return false;
-	}
-
-	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
-		pr_info("KVM is unsupported when running as an SEV guest\n");
-		return false;
-	}
-
-	rdmsrl(MSR_VM_CR, vm_cr);
-	if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE)) {
-		pr_err("SVM disabled (by BIOS) in MSR_VM_CR on CPU %d\n", cpu);
-		return false;
-	}
-
-	return true;
-}
-
-bool kvm_is_svm_supported(void)
-{
-	bool supported;
-
-	migrate_disable();
-	supported = __kvm_is_svm_supported();
-	migrate_enable();
-
-	return supported;
-}
-
 static int svm_check_processor_compat(void)
 {
-	if (!__kvm_is_svm_supported())
+	if (!kvm_is_svm_supported())
 		return -EIO;
 
 	return 0;
diff --git a/arch/x86/kvm/svm/vac.c b/arch/x86/kvm/svm/vac.c
index 2dd1c763f7d6..7c4db99ca7d5 100644
--- a/arch/x86/kvm/svm/vac.c
+++ b/arch/x86/kvm/svm/vac.c
@@ -10,6 +10,49 @@
 DEFINE_PER_CPU(struct svm_cpu_data, svm_data);
 unsigned int max_sev_asid;
 
+static bool __kvm_is_svm_supported(void)
+{
+	int cpu = smp_processor_id();
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+	u64 vm_cr;
+
+	if (c->x86_vendor != X86_VENDOR_AMD &&
+	    c->x86_vendor != X86_VENDOR_HYGON) {
+		pr_err("CPU %d isn't AMD or Hygon\n", cpu);
+		return false;
+	}
+
+	if (!cpu_has(c, X86_FEATURE_SVM)) {
+		pr_err("SVM not supported by CPU %d\n", cpu);
+		return false;
+	}
+
+	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
+		pr_info("KVM is unsupported when running as an SEV guest\n");
+		return false;
+	}
+
+	rdmsrl(MSR_VM_CR, vm_cr);
+	if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE)) {
+		pr_err("SVM disabled (by BIOS) in MSR_VM_CR on CPU %d\n", cpu);
+		return false;
+	}
+
+	return true;
+}
+
+bool kvm_is_svm_supported(void)
+{
+	bool supported;
+
+	migrate_disable();
+	supported = __kvm_is_svm_supported();
+	migrate_enable();
+
+	return supported;
+}
+
 static inline void kvm_cpu_svm_disable(void)
 {
 	uint64_t efer;
diff --git a/arch/x86/kvm/vac.h b/arch/x86/kvm/vac.h
index 6c0a480ee9e3..5be30cce5a1c 100644
--- a/arch/x86/kvm/vac.h
+++ b/arch/x86/kvm/vac.h
@@ -9,9 +9,11 @@ int __init vac_init(void);
 void vac_exit(void);
 
 #ifdef CONFIG_KVM_INTEL
+bool kvm_is_vmx_supported(void);
 int __init vac_vmx_init(void);
 void vac_vmx_exit(void);
 #else
+bool kvm_is_vmx_supported(void) { return false }
 int __init vac_vmx_init(void)
 {
 	return 0;
@@ -20,9 +22,11 @@ void vac_vmx_exit(void) {}
 #endif
 
 #ifdef CONFIG_KVM_AMD
+bool kvm_is_svm_supported(void);
 int __init vac_svm_init(void);
 void vac_svm_exit(void);
 #else
+bool kvm_is_svm_supported(void) { return false }
 int __init vac_svm_init(void)
 {
 	return 0;
diff --git a/arch/x86/kvm/vmx/vac.c b/arch/x86/kvm/vmx/vac.c
index 202686ccbaec..cdfdeb67a719 100644
--- a/arch/x86/kvm/vmx/vac.c
+++ b/arch/x86/kvm/vmx/vac.c
@@ -31,6 +31,35 @@ struct vmcs *vac_get_vmxarea(int cpu)
 static DECLARE_BITMAP(vmx_vpid_bitmap, VMX_NR_VPIDS);
 static DEFINE_SPINLOCK(vmx_vpid_lock);
 
+static bool __kvm_is_vmx_supported(void)
+{
+	int cpu = smp_processor_id();
+
+	if (!(cpuid_ecx(1) & feature_bit(VMX))) {
+		pr_err("VMX not supported by CPU %d\n", cpu);
+		return false;
+	}
+
+	if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
+	    !this_cpu_has(X86_FEATURE_VMX)) {
+		pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL on CPU %d\n", cpu);
+		return false;
+	}
+
+	return true;
+}
+
+bool kvm_is_vmx_supported(void)
+{
+	bool supported;
+
+	migrate_disable();
+	supported = __kvm_is_vmx_supported();
+	migrate_enable();
+
+	return supported;
+}
+
 int allocate_vpid(void)
 {
 	int vpid;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 46e2d5c69d1d..6301b49e0e80 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2625,42 +2625,13 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
 	return 0;
 }
 
-static bool __kvm_is_vmx_supported(void)
-{
-	int cpu = smp_processor_id();
-
-	if (!(cpuid_ecx(1) & feature_bit(VMX))) {
-		pr_err("VMX not supported by CPU %d\n", cpu);
-		return false;
-	}
-
-	if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
-	    !this_cpu_has(X86_FEATURE_VMX)) {
-		pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL on CPU %d\n", cpu);
-		return false;
-	}
-
-	return true;
-}
-
-bool kvm_is_vmx_supported(void)
-{
-	bool supported;
-
-	migrate_disable();
-	supported = __kvm_is_vmx_supported();
-	migrate_enable();
-
-	return supported;
-}
-
 static int vmx_check_processor_compat(void)
 {
 	int cpu = raw_smp_processor_id();
 	struct vmcs_config vmcs_conf;
 	struct vmx_capability vmx_cap;
 
-	if (!__kvm_is_vmx_supported())
+	if (!kvm_is_vmx_supported())
 		return -EIO;
 
 	if (setup_vmcs_config(&vmcs_conf, &vmx_cap) < 0) {
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 322be05e6c5b..1da8efcd3e9c 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -10,18 +10,12 @@
 #include "kvm_emulate.h"
 
 #ifdef CONFIG_KVM_AMD
-bool kvm_is_svm_supported(void);
 int __init svm_init(void);
 void svm_module_exit(void);
-#else
-bool kvm_is_svm_supported(void) { return false; }
 #endif
 #ifdef CONFIG_KVM_INTEL
-bool kvm_is_vmx_supported(void);
 int __init vmx_init(void);
 void vmx_module_exit(void);
-#else
-bool kvm_is_vmx_supported(void) { return false; }
 #endif
 
 struct kvm_caps {
-- 
2.42.0.869.gea05f2083d-goog