[v9,03/18] KVM: SVM: Add KVM_SEV_SEND_FINISH command

Commit Message

Kalra, Ashish Dec. 8, 2020, 10:04 p.m. UTC

From: Brijesh Singh <[e-mail]>

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

Cc: Thomas Gleixner <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Paolo Bonzini <[e-mail]>
Cc: "Radim Krčmář" <[e-mail]>
Cc: Joerg Roedel <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Tom Lendacky <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Reviewed-by: Steve Rutherford <[e-mail]>
Signed-off-by: Brijesh Singh <[e-mail]>
Signed-off-by: Ashish Kalra <[e-mail]>
---
 .../virt/kvm/amd-memory-encryption.rst        |  8 +++++++
 arch/x86/kvm/svm/sev.c                        | 23 +++++++++++++++++++
 2 files changed, 31 insertions(+)

Patch

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 adfe2e53abf3..877780222378 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1167,6 +1167,26 @@  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;
@@ -1217,6 +1237,9 @@  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;