[PATCH v13 03/12] KVM: SVM: Add KVM_SEV_SEND_FINISH command

Ashish Kalra
2021-04-15T15:54:36Z

From: Brijesh Singh <brijesh.singh@amd.com>

The command is used to finailize the encryption context created with
KVM_SEV_SEND_START command.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
---
.../virt/kvm/amd-memory-encryption.rst | 8 +++++++
arch/x86/kvm/svm/sev.c | 23 +++++++++++++++++++
2 files changed, 31 insertions(+)

diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst
index 3c5456e0268a..26c4e6c83f62 100644
--- a/Documentation/virt/kvm/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/amd-memory-encryption.rst
@@ -335,6 +335,14 @@ Returns: 0 on success, -negative on error
__u32 trans_len;
};

+12. KVM_SEV_SEND_FINISH
+------------------------
+
+After completion of the migration flow, the KVM_SEV_SEND_FINISH command can be
+issued by the hypervisor to delete the encryption context.
+
+Returns: 0 on success, -negative on error
+
References
==========

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 30527285a39a..92325d9527ce 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1350,6 +1350,26 @@ static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
return ret;
}

+static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+ struct sev_data_send_finish *data;
+ int ret;
+
+ if (!sev_guest(kvm))
+ return -ENOTTY;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->handle = sev->handle;
+ ret = sev_issue_cmd(kvm, SEV_CMD_SEND_FINISH, data, &argp->error);
+
+ kfree(data);
+ return ret;
+}
+
int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
{
struct kvm_sev_cmd sev_cmd;
@@ -1409,6 +1429,9 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
case KVM_SEV_SEND_UPDATE_DATA:
r = sev_send_update_data(kvm, &sev_cmd);
break;
+ case KVM_SEV_SEND_FINISH:
+ r = sev_send_finish(kvm, &sev_cmd);
+ break;
default:
r = -EINVAL;
goto out;
--
2.17.1