[PATCH v10 03/16] KVM: SVM: Add KVM_SEV_SEND_FINISH command

[Ashish Kalra]

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

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

Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: "Radim Krčmář" <rkrc...@redhat.com>
Cc: Joerg Roedel <j...@8bytes.org>
Cc: Borislav Petkov <b...@suse.de>
Cc: Tom Lendacky <thomas.lenda...@amd.com>
Cc: x...@kernel.org
Cc: k...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.si...@amd.com>
Signed-off-by: Ashish Kalra <ashish.ka...@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 8bed1d801558..0da0c199efa8 100644
--- a/Documentation/virt/kvm/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/amd-memory-encryption.rst
@@ -314,6 +314,14 @@ 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 98e46ae1cba3..0d117b1e6491 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1279,6 +1279,26 @@ 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;
@@ -1335,6 +1355,9 @@ 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