[PATCH 07/10] KVM: x86: Add is_vm_type_supported callback

[Paolo Bonzini]

From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Allow the backend to specify which VM types are supported.

Based on a patch by Isaku Yamahata <isaku.yamahata@xxxxxxxxx>.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
 arch/x86/include/asm/kvm-x86-ops.h | 1 +
 arch/x86/include/asm/kvm_host.h    | 1 +
 arch/x86/kvm/x86.c                 | 9 ++++++++-
 arch/x86/kvm/x86.h                 | 2 ++
 4 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index ac8b7614e79d..8694a6e3d012 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -20,6 +20,7 @@ KVM_X86_OP(hardware_disable)
 KVM_X86_OP(hardware_unsetup)
 KVM_X86_OP(has_emulated_msr)
 KVM_X86_OP(vcpu_after_set_cpuid)
+KVM_X86_OP_OPTIONAL_RET0(is_vm_type_supported)
 KVM_X86_OP(vm_init)
 KVM_X86_OP_OPTIONAL(vm_destroy)
 KVM_X86_OP_OPTIONAL_RET0(vcpu_precreate)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b7d33205d49d..9636a43ccdc4 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1601,6 +1601,7 @@ struct kvm_x86_ops {
 	bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
 	void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
 
+	bool (*is_vm_type_supported)(unsigned long vm_type);
 	unsigned int vm_size;
 	int (*vm_init)(struct kvm *kvm);
 	void (*vm_destroy)(struct kvm *kvm);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e634e5b67516..c89ddaa1e09f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4581,12 +4581,19 @@ static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,
 }
 #endif
 
-static bool kvm_is_vm_type_supported(unsigned long type)
+bool __kvm_is_vm_type_supported(unsigned long type)
 {
 	return type == KVM_X86_DEFAULT_VM ||
 	       (type == KVM_X86_SW_PROTECTED_VM &&
 		IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);
 }
+EXPORT_SYMBOL_GPL(__kvm_is_vm_type_supported);
+
+static bool kvm_is_vm_type_supported(unsigned long type)
+{
+	return __kvm_is_vm_type_supported(type) ||
+	       static_call(kvm_x86_is_vm_type_supported)(type);
+}
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 {
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 2f7e19166658..4e40c23d66ed 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -9,6 +9,8 @@
 #include "kvm_cache_regs.h"
 #include "kvm_emulate.h"
 
+bool __kvm_is_vm_type_supported(unsigned long type);
+
 struct kvm_caps {
 	/* control of guest tsc rate supported? */
 	bool has_tsc_control;
-- 
2.39.0