Add vm subcommand to check support for protected and unprotected VMs.

Test: adb shell /apex/com.android.virt/bin/vm info
Change-Id: I9ed881a82818edacb81446b7684e90ae684bf1e8

vm/Android.bp

@@ -15,6 +15,7 @@ rust_binary {
         "liblibc",
         "liblog_rust",
         "libmicrodroid_payload_config",
+        "librustutils",
         "libserde_json",
         "libserde",
         "libstructopt",

vm/src/main.rs

@@ -26,7 +26,8 @@ use android_system_virtualizationservice::binder::{wait_for_interface, ProcessSt
 use anyhow::{Context, Error};
 use create_partition::command_create_partition;
 use run::{command_run, command_run_app};
-use std::path::PathBuf;
+use rustutils::system_properties;
+use std::path::{Path, PathBuf};
 use structopt::clap::AppSettings;
 use structopt::StructOpt;
 
@@ -126,6 +127,8 @@ enum Opt {
     },
     /// List running virtual machines
     List,
+    /// Print information about virtual machine support
+    Info,
     /// Create a new empty partition to be used as a writable partition for a VM
     CreatePartition {
         /// Path at which to create the image file
@@ -212,6 +215,7 @@ fn main() -> Result<(), Error> {
         }
         Opt::Stop { cid } => command_stop(service, cid),
         Opt::List => command_list(service),
+        Opt::Info => command_info(),
         Opt::CreatePartition { path, size, partition_type } => {
             command_create_partition(service, &path, size, partition_type)
         }
@@ -233,3 +237,31 @@ fn command_list(service: Strong<dyn IVirtualizationService>) -> Result<(), Error
     println!("Running VMs: {:#?}", vms);
     Ok(())
 }
+
+/// Print information about supported VM types.
+fn command_info() -> Result<(), Error> {
+    let unprotected_vm_supported =
+        system_properties::read_bool("ro.boot.hypervisor.vm.supported", false)?;
+    let protected_vm_supported =
+        system_properties::read_bool("ro.boot.hypervisor.protected_vm.supported", false)?;
+    match (unprotected_vm_supported, protected_vm_supported) {
+        (false, false) => println!("VMs are not supported."),
+        (false, true) => println!("Only protected VMs are supported."),
+        (true, false) => println!("Only unprotected VMs are supported."),
+        (true, true) => println!("Both protected and unprotected VMs are supported."),
+    }
+
+    if let Ok(version) = system_properties::read("ro.boot.hypervisor.version") {
+        println!("Hypervisor version: {}", version);
+    } else {
+        println!("Hypervisor version not set.");
+    }
+
+    if Path::new("/dev/kvm").exists() {
+        println!("/dev/kvm exists.");
+    } else {
+        println!("/dev/kvm does not exist.");
+    }
+
+    Ok(())
+}