1 files changed, 72 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1453248723e..f5c60a84fcf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4136,6 +4136,78 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
 	return 1;
 }
 
+struct read_write_emulator_ops {
+	int (*read_write_prepare)(struct kvm_vcpu *vcpu, void *val,
+				  int bytes);
+	int (*read_write_emulate)(struct kvm_vcpu *vcpu, gpa_t gpa,
+				  void *val, int bytes);
+	int (*read_write_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
+			       int bytes, void *val);
+	int (*read_write_exit_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
+				    void *val, int bytes);
+	bool write;
+};
+
+static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes)
+{
+	if (vcpu->mmio_read_completed) {
+		memcpy(val, vcpu->mmio_data, bytes);
+		trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
+			       vcpu->mmio_phys_addr, *(u64 *)val);
+		vcpu->mmio_read_completed = 0;
+		return 1;
+	}
+
+	return 0;
+}
+
+static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
+			void *val, int bytes)
+{
+	return !kvm_read_guest(vcpu->kvm, gpa, val, bytes);
+}
+
+static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
+			 void *val, int bytes)
+{
+	return emulator_write_phys(vcpu, gpa, val, bytes);
+}
+
+static int write_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val)
+{
+	trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, *(u64 *)val);
+	return vcpu_mmio_write(vcpu, gpa, bytes, val);
+}
+
+static int read_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
+			  void *val, int bytes)
+{
+	trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, 0);
+	return X86EMUL_IO_NEEDED;
+}
+
+static int write_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
+			   void *val, int bytes)
+{
+	memcpy(vcpu->mmio_data, val, bytes);
+	memcpy(vcpu->run->mmio.data, vcpu->mmio_data, 8);
+	return X86EMUL_CONTINUE;
+}
+
+static struct read_write_emulator_ops read_emultor = {
+	.read_write_prepare = read_prepare,
+	.read_write_emulate = read_emulate,
+	.read_write_mmio = vcpu_mmio_read,
+	.read_write_exit_mmio = read_exit_mmio,
+};
+
+static struct read_write_emulator_ops write_emultor = {
+	.read_write_emulate = write_emulate,
+	.read_write_mmio = write_mmio,
+	.read_write_exit_mmio = write_exit_mmio,
+	.write = true,
+};
+
 static int emulator_write_emulated_onepage(unsigned long addr,
 					   const void *val,
 					   unsigned int bytes,