After completion of SEND_START, but before SEND_FINISH, the source VMM can
issue the SEND_CANCEL command to stop a migration. This is necessary so
that a cancelled migration can restart with a new target later.
Signed-off-by: Steve Rutherford <srutherford@xxxxxxxxxx>
---
.../virt/kvm/amd-memory-encryption.rst | 9 +++++++
arch/x86/kvm/svm/sev.c | 24 +++++++++++++++++++
include/linux/psp-sev.h | 10 ++++++++
include/uapi/linux/kvm.h | 2 ++
4 files changed, 45 insertions(+)
diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst
index 469a6308765b1..9e018a3eec03b 100644
--- a/Documentation/virt/kvm/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/amd-memory-encryption.rst
@@ -284,6 +284,15 @@ Returns: 0 on success, -negative on error
__u32 len;
};
+16. KVM_SEV_SEND_CANCEL
+------------------------
+
+After completion of SEND_START, but before SEND_FINISH, the source VMM can issue the
+SEND_CANCEL command to stop a migration. This is necessary so that a cancelled
+migration can restart with a new target later.
+
+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 83e00e5245136..88e72102cb900 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1110,6 +1110,27 @@ static int sev_get_attestation_report(struct kvm *kvm, struct kvm_sev_cmd *argp)
return ret;
}
+static int sev_send_cancel(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+ struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+ struct sev_data_send_cancel *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_CANCEL, data, &argp->error);
+
+ kfree(data);
+ return ret;
+}
+
+
int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
{
struct kvm_sev_cmd sev_cmd;
@@ -1163,6 +1184,9 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
case KVM_SEV_GET_ATTESTATION_REPORT:
r = sev_get_attestation_report(kvm, &sev_cmd);
break;
+ case KVM_SEV_SEND_CANCEL:
+ r = sev_send_cancel(kvm, &sev_cmd);
+ break;
default:
r = -EINVAL;
goto out;
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index b801ead1e2bb5..74f2babffc574 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -73,6 +73,7 @@ enum sev_cmd {
SEV_CMD_SEND_UPDATE_DATA = 0x041,
SEV_CMD_SEND_UPDATE_VMSA = 0x042,
SEV_CMD_SEND_FINISH = 0x043,
+ SEV_CMD_SEND_CANCEL = 0x044,
/* Guest migration commands (incoming) */
SEV_CMD_RECEIVE_START = 0x050,
@@ -392,6 +393,15 @@ struct sev_data_send_finish {
u32 handle; /* In */
} __packed;
+/**
+ * struct sev_data_send_cancel - SEND_CANCEL command parameters
+ *
+ * @handle: handle of the VM to process
+ */
+struct sev_data_send_cancel {
+ u32 handle; /* In */
+} __packed;
+
/**
* struct sev_data_receive_start - RECEIVE_START command parameters
*
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index f6afee209620d..707469b6b7072 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1671,6 +1671,8 @@ enum sev_cmd_id {
KVM_SEV_CERT_EXPORT,
/* Attestation report */
KVM_SEV_GET_ATTESTATION_REPORT,
+ /* Guest Migration Extension */
+ KVM_SEV_SEND_CANCEL,
KVM_SEV_NR_MAX,
};
--
2.31.0.208.g409f899ff0-goog
