From 46ba7487ec8808e771fd4f0947f398fe4fc2c79c Mon Sep 17 00:00:00 2001
From: Patrick Roy <roypat@amazon.co.uk>
Date: Fri, 15 Nov 2024 10:33:18 +0000
Subject: [PATCH] refactor: Remove some getters and setters for boot_source

The initialization code for the `boot_source` field in
`build_boot_source` had me do a double take when I first saw, with all
the setters and getters obscuring what is really happening. Clean this
up by simply using a struct initializer, and also remove the getters and
setters altogether, since all the fields are pub anyway.

Signed-off-by: Patrick Roy <roypat@amazon.co.uk>
---
 src/vmm/src/builder.rs   |  6 ++++--
 src/vmm/src/persist.rs   |  2 +-
 src/vmm/src/resources.rs | 37 ++++++++-----------------------------
 3 files changed, 13 insertions(+), 32 deletions(-)

diff --git a/src/vmm/src/builder.rs b/src/vmm/src/builder.rs
index 1f52fdad063..3355633e3c8 100644
--- a/src/vmm/src/builder.rs
+++ b/src/vmm/src/builder.rs
@@ -259,7 +259,9 @@ pub fn build_microvm_for_boot(
     let request_ts = TimestampUs::default();
 
     let boot_config = vm_resources
-        .boot_source_builder()
+        .boot_source
+        .builder
+        .as_ref()
         .ok_or(MissingKernelConfig)?;
 
     let guest_memory = vm_resources
@@ -508,7 +510,7 @@ pub fn build_microvm_from_snapshot(
     vmm.vm.restore_state(&microvm_state.vm_state)?;
 
     // Restore the boot source config paths.
-    vm_resources.set_boot_source_config(microvm_state.vm_info.boot_source);
+    vm_resources.boot_source.config = microvm_state.vm_info.boot_source;
 
     // Restore devices states.
     let mmio_ctor_args = MMIODevManagerConstructorArgs {
diff --git a/src/vmm/src/persist.rs b/src/vmm/src/persist.rs
index 5b01ed49c75..3479e0b6309 100644
--- a/src/vmm/src/persist.rs
+++ b/src/vmm/src/persist.rs
@@ -64,7 +64,7 @@ impl From<&VmResources> for VmInfo {
             mem_size_mib: value.vm_config.mem_size_mib as u64,
             smt: value.vm_config.smt,
             cpu_template: StaticCpuTemplate::from(&value.vm_config.cpu_template),
-            boot_source: value.boot_source_config().clone(),
+            boot_source: value.boot_source.config.clone(),
             huge_pages: value.vm_config.huge_pages,
         }
     }
diff --git a/src/vmm/src/resources.rs b/src/vmm/src/resources.rs
index a4d15641975..0ad4df8aa19 100644
--- a/src/vmm/src/resources.rs
+++ b/src/vmm/src/resources.rs
@@ -315,16 +315,6 @@ impl VmResources {
         mmds_config
     }
 
-    /// Gets a reference to the boot source configuration.
-    pub fn boot_source_config(&self) -> &BootSourceConfig {
-        &self.boot_source.config
-    }
-
-    /// Gets a reference to the boot source builder.
-    pub fn boot_source_builder(&self) -> Option<&BootConfig> {
-        self.boot_source.builder.as_ref()
-    }
-
     /// Sets a balloon device to be attached when the VM starts.
     pub fn set_balloon_device(
         &mut self,
@@ -354,14 +344,12 @@ impl VmResources {
             return Err(BootSourceConfigError::HugePagesAndInitRd);
         }
 
-        self.set_boot_source_config(boot_source_cfg);
-        self.boot_source.builder = Some(BootConfig::new(self.boot_source_config())?);
-        Ok(())
-    }
+        self.boot_source = BootSource {
+            builder: Some(BootConfig::new(&boot_source_cfg)?),
+            config: boot_source_cfg,
+        };
 
-    /// Set the boot source configuration (contains raw kernel config details).
-    pub fn set_boot_source_config(&mut self, boot_source_cfg: BootSourceConfig) {
-        self.boot_source.config = boot_source_cfg;
+        Ok(())
     }
 
     /// Inserts a block to be attached when the VM starts.
@@ -512,7 +500,7 @@ impl From<&VmResources> for VmmConfig {
         VmmConfig {
             balloon_device: resources.balloon.get_config().ok(),
             block_devices: resources.block.configs(),
-            boot_source: resources.boot_source_config().clone(),
+            boot_source: resources.boot_source.config.clone(),
             cpu_config: None,
             logger: None,
             machine_config: Some(MachineConfig::from(&resources.vm_config)),
@@ -1521,15 +1509,6 @@ mod tests {
         assert_eq!(actual_entropy_cfg, entropy_device_cfg);
     }
 
-    #[test]
-    fn test_boot_config() {
-        let vm_resources = default_vm_resources();
-        let expected_boot_cfg = vm_resources.boot_source.builder.as_ref().unwrap();
-        let actual_boot_cfg = vm_resources.boot_source_builder().unwrap();
-
-        assert!(actual_boot_cfg == expected_boot_cfg);
-    }
-
     #[test]
     fn test_set_boot_source() {
         let tmp_file = TempFile::new().unwrap();
@@ -1541,7 +1520,7 @@ mod tests {
         };
 
         let mut vm_resources = default_vm_resources();
-        let boot_builder = vm_resources.boot_source_builder().unwrap();
+        let boot_builder = vm_resources.boot_source.builder.as_ref().unwrap();
         let tmp_ino = tmp_file.as_file().metadata().unwrap().st_ino();
 
         assert_ne!(
@@ -1568,7 +1547,7 @@ mod tests {
         );
 
         vm_resources.build_boot_source(expected_boot_cfg).unwrap();
-        let boot_source_builder = vm_resources.boot_source_builder().unwrap();
+        let boot_source_builder = vm_resources.boot_source.builder.unwrap();
         assert_eq!(
             boot_source_builder
                 .cmdline