KVM: X86: Introduce generic guest-mode representation

This patch introduces a generic representation of guest-mode
fpr a vcpu. This currently only exists in the SVM code.
Having this representation generic will help making the
non-svm code aware of nesting when this is necessary.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

2 files changed, 16 insertions, 0 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 0c0941db31c4..56e45a2ed2de 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -779,6 +779,7 @@ enum {
 #define HF_VINTR_MASK           (1 << 2)
 #define HF_NMI_MASK             (1 << 3)
 #define HF_IRET_MASK            (1 << 4)
+#define HF_GUEST_MASK           (1 << 5) /* VCPU is in guest-mode */
 
 /*
  * Hardware virtualization extension instructions may fault if a
diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 975bb45329a1..95ac3afa6e6f 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -84,4 +84,19 @@ static inline u64 kvm_read_edx_eax(struct kvm_vcpu *vcpu)
                 | ((u64)(kvm_register_read(vcpu, VCPU_REGS_RDX) & -1u) << 32);
 }
 
+static inline void enter_guest_mode(struct kvm_vcpu *vcpu)
+{
+        vcpu->arch.hflags |= HF_GUEST_MASK;
+}
+
+static inline void leave_guest_mode(struct kvm_vcpu *vcpu)
+{
+        vcpu->arch.hflags &= ~HF_GUEST_MASK;
+}
+
+static inline bool is_guest_mode(struct kvm_vcpu *vcpu)
+{
+        return vcpu->arch.hflags & HF_GUEST_MASK;
+}
+
 #endif