From aabfc9513ec7f52204039347a15638bde75f5078 Mon Sep 17 00:00:00 2001
From: Muminul Islam <muislam@microsoft.com>
Date: Wed, 1 May 2024 14:46:04 -0700
Subject: [PATCH] hypervisor: implement pause/resume API for MSHV

Implementing pause/Resume API for MSHV.
Here we set/reset the partition property(TIME_FREEZE)

Signed-off-by: Muminul Islam <muislam@microsoft.com>
---
 hypervisor/src/mshv/mod.rs | 32 ++++++++++++++++++++++++++++++++
 hypervisor/src/vm.rs       |  4 ++++
 2 files changed, 36 insertions(+)

diff --git a/hypervisor/src/mshv/mod.rs b/hypervisor/src/mshv/mod.rs
index b1b3a9c6c..bd5e9dfb3 100644
--- a/hypervisor/src/mshv/mod.rs
+++ b/hypervisor/src/mshv/mod.rs
@@ -2076,4 +2076,36 @@ impl vm::Vm for MshvVm {
     fn get_preferred_target(&self, kvi: &mut VcpuInit) -> vm::Result<()> {
         unimplemented!()
     }
+
+    /// Pause the VM
+    fn pause(&self) -> vm::Result<()> {
+        // Freeze the partition
+        self.fd
+            .set_partition_property(
+                hv_partition_property_code_HV_PARTITION_PROPERTY_TIME_FREEZE,
+                1u64,
+            )
+            .map_err(|e| {
+                vm::HypervisorVmError::SetVmProperty(anyhow!(
+                    "Failed to set partition property: {}",
+                    e
+                ))
+            })
+    }
+
+    /// Resume the VM
+    fn resume(&self) -> vm::Result<()> {
+        // Resuming the partition using TIME_FREEZE property
+        self.fd
+            .set_partition_property(
+                hv_partition_property_code_HV_PARTITION_PROPERTY_TIME_FREEZE,
+                0u64,
+            )
+            .map_err(|e| {
+                vm::HypervisorVmError::SetVmProperty(anyhow!(
+                    "Failed to set partition property: {}",
+                    e
+                ))
+            })
+    }
 }
diff --git a/hypervisor/src/vm.rs b/hypervisor/src/vm.rs
index bf57f2342..ed15ed9db 100644
--- a/hypervisor/src/vm.rs
+++ b/hypervisor/src/vm.rs
@@ -231,6 +231,10 @@ pub enum HypervisorVmError {
     ///
     #[error("Failed to complete isolated import: {0}")]
     CompleteIsolatedImport(#[source] anyhow::Error),
+    /// Failed to set VM property
+    ///
+    #[error("Failed to set VM property: {0}")]
+    SetVmProperty(#[source] anyhow::Error),
 }
 ///
 /// Result type for returning from a function