From 9c5135da7a241f658ca3666fe6e3cc55eebc0666 Mon Sep 17 00:00:00 2001
From: Samuel Ortiz <sameo@linux.intel.com>
Date: Tue, 24 Sep 2019 01:03:05 +0200
Subject: [PATCH] vmm: Simplify the VM start flow

We can integrate the kernel loading into the VM start method.
The VM start flow is then: Vm::new() -> vm.start(), which feels more
natural.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
---
 vmm/src/lib.rs | 8 +-------
 vmm/src/vm.rs  | 7 +++----
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/vmm/src/lib.rs b/vmm/src/lib.rs
index b47f95cd9..58a53b933 100644
--- a/vmm/src/lib.rs
+++ b/vmm/src/lib.rs
@@ -26,9 +26,6 @@ pub enum Error {
 
     /// Cannot start a VM.
     VmStart(vm::Error),
-
-    /// Cannot load a kernel.
-    LoadKernel(vm::Error),
 }
 pub type Result<T> = result::Result<T, Error>;
 
@@ -39,7 +36,6 @@ impl Display for Error {
         match self {
             VmNew(e) => write!(f, "Can not create a new virtual machine: {:?}", e),
             VmStart(e) => write!(f, "Can not start a new virtual machine: {:?}", e),
-            LoadKernel(e) => write!(f, "Can not load a guest kernel: {:?}", e),
         }
     }
 }
@@ -60,9 +56,7 @@ pub fn boot_kernel(config: VmConfig) -> Result<()> {
         let vmm = Vmm::new()?;
         let mut vm = Vm::new(&vmm.kvm, &config).map_err(Error::VmNew)?;
 
-        let entry = vm.load_kernel().map_err(Error::LoadKernel)?;
-
-        if vm.start(entry).map_err(Error::VmStart)? == ExitBehaviour::Shutdown {
+        if vm.start().map_err(Error::VmStart)? == ExitBehaviour::Shutdown {
             break;
         }
 
diff --git a/vmm/src/vm.rs b/vmm/src/vm.rs
index 9e59827e0..ce6c553cc 100755
--- a/vmm/src/vm.rs
+++ b/vmm/src/vm.rs
@@ -766,7 +766,7 @@ impl<'a> Vm<'a> {
         })
     }
 
-    pub fn load_kernel(&mut self) -> Result<GuestAddress> {
+    fn load_kernel(&mut self) -> Result<GuestAddress> {
         let mut cmdline = self.config.cmdline.args.clone();
         for entry in self.devices.cmdline_additions() {
             cmdline.insert_str(entry).map_err(|_| Error::CmdLine)?;
@@ -956,10 +956,9 @@ impl<'a> Vm<'a> {
         }
     }
 
-    pub fn start(&mut self, entry_addr: GuestAddress) -> Result<ExitBehaviour> {
+    pub fn start(&mut self) -> Result<ExitBehaviour> {
+        let entry_addr = self.load_kernel()?;
         let vcpu_count = u8::from(&self.config.cpus);
-
-        //        let vcpus: Vec<thread::JoinHandle<()>> = Vec::with_capacity(vcpu_count as usize);
         let vcpu_thread_barrier = Arc::new(Barrier::new((vcpu_count + 1) as usize));
 
         for cpu_id in 0..vcpu_count {