Merge VM and CDISK config into libvmconfig
so that virtualizationservice and vm use it.
Bug: 190503456
Test: MicrodroidHostTestCases
Change-Id: I63eaf0ac1c6d0e1e17d19f4863c5f4f14525aa32
diff --git a/vmconfig/Android.bp b/vmconfig/Android.bp
new file mode 100644
index 0000000..321eba0
--- /dev/null
+++ b/vmconfig/Android.bp
@@ -0,0 +1,19 @@
+package {
+ default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+rust_library {
+ name: "libvmconfig",
+ crate_name: "vmconfig",
+ srcs: ["src/lib.rs"],
+ edition: "2018",
+ rustlibs: [
+ "android.system.virtualizationservice-rust",
+ "libanyhow",
+ "libserde_json",
+ "libserde",
+ ],
+ apex_available: [
+ "com.android.virt",
+ ],
+}
diff --git a/vmconfig/src/lib.rs b/vmconfig/src/lib.rs
new file mode 100644
index 0000000..c9385f3
--- /dev/null
+++ b/vmconfig/src/lib.rs
@@ -0,0 +1,175 @@
+// Copyright 2021, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Struct for VM configuration with JSON (de)serialization and AIDL parcelables
+
+use android_system_virtualizationservice::{
+ aidl::android::system::virtualizationservice::DiskImage::DiskImage as AidlDiskImage,
+ aidl::android::system::virtualizationservice::Partition::Partition as AidlPartition,
+ aidl::android::system::virtualizationservice::VirtualMachineConfig::VirtualMachineConfig,
+ binder::ParcelFileDescriptor,
+};
+
+use anyhow::{bail, Context, Error, Result};
+use serde::{Deserialize, Serialize};
+use std::fs::{File, OpenOptions};
+use std::io::BufReader;
+use std::path::{Path, PathBuf};
+
+/// Configuration for a particular VM to be started.
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+pub struct VmConfig {
+ /// The filename of the kernel image, if any.
+ pub kernel: Option<PathBuf>,
+ /// The filename of the initial ramdisk for the kernel, if any.
+ pub initrd: Option<PathBuf>,
+ /// Parameters to pass to the kernel. As far as the VMM and boot protocol are concerned this is
+ /// just a string, but typically it will contain multiple parameters separated by spaces.
+ pub params: Option<String>,
+ /// The bootloader to use. If this is supplied then the kernel and initrd must not be supplied;
+ /// the bootloader is instead responsibly for loading the kernel from one of the disks.
+ pub bootloader: Option<PathBuf>,
+ /// Disk images to be made available to the VM.
+ #[serde(default)]
+ pub disks: Vec<DiskImage>,
+ /// Whether the VM should be a protected VM.
+ #[serde(default)]
+ pub protected: bool,
+}
+
+impl VmConfig {
+ /// Ensure that the configuration has a valid combination of fields set, or return an error if
+ /// not.
+ pub fn validate(&self) -> Result<(), Error> {
+ if self.bootloader.is_none() && self.kernel.is_none() {
+ bail!("VM must have either a bootloader or a kernel image.");
+ }
+ if self.bootloader.is_some() && (self.kernel.is_some() || self.initrd.is_some()) {
+ bail!("Can't have both bootloader and kernel/initrd image.");
+ }
+ for disk in &self.disks {
+ if disk.image.is_none() == disk.partitions.is_empty() {
+ bail!("Exactly one of image and partitions must be specified. (Was {:?}.)", disk);
+ }
+ }
+ Ok(())
+ }
+
+ /// Load the configuration for a VM from the given JSON file, and check that it is valid.
+ pub fn load(file: &File) -> Result<VmConfig, Error> {
+ let buffered = BufReader::new(file);
+ let config: VmConfig = serde_json::from_reader(buffered)?;
+ config.validate()?;
+ Ok(config)
+ }
+
+ /// Convert the `VmConfig` to a [`VirtualMachineConfig`] which can be passed to the Virt
+ /// Manager.
+ pub fn to_parcelable(&self) -> Result<VirtualMachineConfig, Error> {
+ Ok(VirtualMachineConfig {
+ kernel: maybe_open_parcel_file(&self.kernel, false)?,
+ initrd: maybe_open_parcel_file(&self.initrd, false)?,
+ params: self.params.clone(),
+ bootloader: maybe_open_parcel_file(&self.bootloader, false)?,
+ disks: self.disks.iter().map(DiskImage::to_parcelable).collect::<Result<_, Error>>()?,
+ protected_vm: self.protected,
+ })
+ }
+}
+
+/// A disk image to be made available to the VM.
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+pub struct DiskImage {
+ /// The filename of the disk image, if it already exists. Exactly one of this and `partitions`
+ /// must be specified.
+ #[serde(default)]
+ pub image: Option<PathBuf>,
+ /// A set of partitions to be assembled into a composite image.
+ #[serde(default)]
+ pub partitions: Vec<Partition>,
+ /// Whether this disk should be writable by the VM.
+ pub writable: bool,
+}
+
+impl DiskImage {
+ fn to_parcelable(&self) -> Result<AidlDiskImage, Error> {
+ let partitions =
+ self.partitions.iter().map(Partition::to_parcelable).collect::<Result<_>>()?;
+ Ok(AidlDiskImage {
+ image: maybe_open_parcel_file(&self.image, self.writable)?,
+ writable: self.writable,
+ partitions,
+ })
+ }
+}
+
+/// A partition to be assembled into a composite image.
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+pub struct Partition {
+ /// A label for the partition.
+ pub label: String,
+ /// The filename of the partition image.
+ #[serde(default)]
+ pub path: Option<PathBuf>,
+ /// The filename of the partition image.
+ #[serde(default)]
+ pub paths: Vec<PathBuf>,
+ /// Whether the partition should be writable.
+ #[serde(default)]
+ pub writable: bool,
+}
+
+impl Partition {
+ fn to_parcelable(&self) -> Result<AidlPartition> {
+ if !self.paths.is_empty() {
+ if self.path.is_some() {
+ bail!("Partition {} contains both path/paths", &self.label);
+ }
+ let images = self
+ .paths
+ .iter()
+ .map(|path| open_parcel_file(&path, self.writable))
+ .collect::<Result<Vec<_>, _>>()?;
+ Ok(AidlPartition { images, writable: self.writable, label: self.label.to_owned() })
+ } else {
+ let path = self.path.as_ref().ok_or_else(|| {
+ Error::msg(format!("Partition {} doesn't set path/paths", &self.label))
+ })?;
+ Ok(AidlPartition {
+ images: vec![open_parcel_file(&path, self.writable)?],
+ writable: self.writable,
+ label: self.label.to_owned(),
+ })
+ }
+ }
+}
+
+/// Try to open the given file and wrap it in a [`ParcelFileDescriptor`].
+fn open_parcel_file(filename: &Path, writable: bool) -> Result<ParcelFileDescriptor> {
+ Ok(ParcelFileDescriptor::new(
+ OpenOptions::new()
+ .read(true)
+ .write(writable)
+ .open(filename)
+ .with_context(|| format!("Failed to open {:?}", filename))?,
+ ))
+}
+
+/// If the given filename is `Some`, try to open it and wrap it in a [`ParcelFileDescriptor`].
+fn maybe_open_parcel_file(
+ filename: &Option<PathBuf>,
+ writable: bool,
+) -> Result<Option<ParcelFileDescriptor>> {
+ filename.as_deref().map(|filename| open_parcel_file(filename, writable)).transpose()
+}