[RFC PATCH v2 23/32] kvm: introduce KVM_MEMORY_ENCRYPT_OP ioctl

From: Brijesh Singh <brijesh.singh@amd.com>
To: <simon.guinot@sequanux.org>, <linux-efi@vger.kernel.org>,
	<brijesh.singh@amd.com>, <kvm@vger.kernel.org>,
	<rkrcmar@redhat.com>, <matt@codeblueprint.co.uk>,
	<linux-pci@vger.kernel.org>, <linus.walleij@linaro.org>,
	<gary.hook@amd.com>, <linux-mm@kvack.org>,
	<paul.gortmaker@windriver.com>, <hpa@zytor.com>, <cl@linux.com>,
	<dan.j.williams@intel.com>, <aarcange@redhat.com>,
	<sfr@canb.auug.org.au>, <andriy.shevchenko@linux.intel.com>,
	<herbert@gondor.apana.org.au>, <bhe@redhat.com>,
	<xemul@parallels.com>, <joro@8bytes.org>, <x86@kernel.org>,
	<peterz@infradead.org>, <piotr.luc@intel.com>, <mingo@redhat.com>,
	<msalter@redhat.com>, <ross.zwisler@linux.intel.com>,
	<bp@suse.de>, <dyoung@redhat.com>, <thomas.lendacky@amd.com>,
	<jroedel@suse.de>, <keescook@chromium.org>, <arnd@arndb.de>,
	<toshi.kani@hpe.com>, <mathieu.desnoyers@efficios.com>,
	<luto@kernel.org>, <devel@linuxdriverproject.org>,
	<bhelgaas@google.com>, <tglx@linutronix.de>, <mchehab@kernel.org>,
	<iamjoonsoo.kim@lge.com>, <labbott@fedoraproject.org>,
	<tony.luck@intel.com>, <alexandre.bounine@idt.com>,
	<kuleshovmail@gmail.com>, <linux-kernel@vger.kernel.org>,
	<mcgrof@kernel.org>, <mst@redhat.com>,
	<linux-crypto@vger.kernel.org>, <tj@kernel.org>,
	<pbonzini@redhat.com>, <akpm@linux-foundation.org>,
	<davem@davemloft.net>
Subject: [RFC PATCH v2 23/32] kvm: introduce KVM_MEMORY_ENCRYPT_OP ioctl
Date: Thu, 2 Mar 2017 10:17:11 -0500	[thread overview]
Message-ID: <148846783136.2349.9362218518503742320.stgit@brijesh-build-machine> (raw)
In-Reply-To: <148846752022.2349.13667498174822419498.stgit@brijesh-build-machine>

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>
---
 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 bff1f15..62651ad 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1033,6 +1033,8 @@ 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 2099df8..6a737e9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3926,6 +3926,14 @@ 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)
 {
@@ -4189,6 +4197,10 @@ 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 = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
 	}
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index cac48ed..fef7d83 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1281,6 +1281,8 @@ struct kvm_s390_ucas_mapping {
 #define KVM_S390_GET_IRQ_STATE	  _IOW(KVMIO, 0xb6, struct kvm_s390_irq_state)
 /* Available with KVM_CAP_X86_SMM */
 #define KVM_SMI                   _IO(KVMIO,   0xb7)
+/* Memory Encryption Commands */
+#define KVM_MEMORY_ENCRYPT_OP	  _IOWR(KVMIO, 0xb8, unsigned long)
 
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)
 #define KVM_DEV_ASSIGN_PCI_2_3		(1 << 1)
