[RFC Part2 PATCH v3 09/26] KVM: Introduce KVM_MEMORY_ENCRYPT_OP ioctl

[Brijesh Singh <brijesh.singh@amd.com>]

If hardware supports encrypting then KVM_MEMORY_ENCRYPT_OP ioctl can
be used by qemu to issue platform specific memory encryption commands.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h |  2 ++
 arch/x86/kvm/x86.c              | 12 ++++++++++++
 include/uapi/linux/kvm.h        |  2 ++
 3 files changed, 16 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7cbaab5..99a0e11 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1057,6 +1057,8 @@ struct kvm_x86_ops {
 	void (*cancel_hv_timer)(struct kvm_vcpu *vcpu);
 
 	void (*setup_mce)(struct kvm_vcpu *vcpu);
+
+	int (*memory_encryption_op)(struct kvm *kvm, void __user *argp);
 };
 
 struct kvm_arch_async_pf {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 88be1aa..c9d3ff5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3974,6 +3974,14 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 	return r;
 }
 
+static int kvm_vm_ioctl_memory_encryption_op(struct kvm *kvm, void __user *argp)
+{
+	if (kvm_x86_ops->memory_encryption_op)
+		return kvm_x86_ops->memory_encryption_op(kvm, argp);
+
+	return -ENOTTY;
+}
+
 long kvm_arch_vm_ioctl(struct file *filp,
 		       unsigned int ioctl, unsigned long arg)
 {
@@ -4234,6 +4242,10 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
 		break;
 	}
+	case KVM_MEMORY_ENCRYPT_OP: {
+		r = kvm_vm_ioctl_memory_encryption_op(kvm, argp);
+		break;
+	}
 	default:
 		r = -ENOTTY;
 	}
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 6cd63c1..ab3b711 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1355,6 +1355,8 @@ struct kvm_s390_ucas_mapping {
 /* Available with KVM_CAP_S390_CMMA_MIGRATION */
 #define KVM_S390_GET_CMMA_BITS      _IOWR(KVMIO, 0xb8, struct kvm_s390_cmma_log)
 #define KVM_S390_SET_CMMA_BITS      _IOW(KVMIO, 0xb9, struct kvm_s390_cmma_log)
+/* Memory Encryption Commands */
+#define KVM_MEMORY_ENCRYPT_OP	  _IOWR(KVMIO, 0xba, unsigned long)
 
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)
 #define KVM_DEV_ASSIGN_PCI_2_3		(1 << 1)
-- 
2.9.4