vmm, arch, devices: Put ACPI support behind a default feature

Put the ACPI support behind a feature and ensure that the code compiles
without that feature by adding an extra build to Travis.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

.travis.yml

@@ -9,6 +9,7 @@ before_script:
 
 script:
   - cargo build --release
+  - cargo build --release --no-default-features
   - cargo test
   - cargo clippy --all-targets --all-features -- -D warnings
   - find . -name "*.rs" | xargs rustfmt --check

arch/Cargo.toml

@@ -3,13 +3,17 @@ name = "arch"
 version = "0.1.0"
 authors = ["The Chromium OS Authors"]
 
+[features]
+default = ["acpi"]
+acpi = ["acpi_tables"]
+
 [dependencies]
 byteorder = "1.3.2"
 kvm-bindings = "0.1.1"
 kvm-ioctls = { git = "https://github.com/rust-vmm/kvm-ioctls", branch = "master" }
 libc = "0.2.60"
 
-acpi_tables = { path ="../acpi_tables" }
+acpi_tables = { path = "../acpi_tables", optional = true }
 arch_gen = { path = "../arch_gen" }
 
 [dependencies.vm-memory]

arch/src/x86_64/acpi.rs

@@ -48,7 +48,7 @@ struct PCIRangeEntry {
     pub segment: u16,
     pub start: u8,
     pub end: u8,
-    _reserved: u32
+    _reserved: u32,
 }
 
 pub fn create_dsdt_table(serial_enabled: bool) -> SDT {

arch/src/x86_64/mod.rs

@@ -183,8 +183,11 @@ pub fn configure_system(
         }
     }
 
-    let rsdp_addr = acpi::create_acpi_tables(guest_mem, num_cpus, serial_enabled);
-    params.0.acpi_rsdp_addr = rsdp_addr.0;
+    #[cfg(feature = "acpi")]
+    {
+        let rsdp_addr = acpi::create_acpi_tables(guest_mem, num_cpus, serial_enabled);
+        params.0.acpi_rsdp_addr = rsdp_addr.0;
+    }
 
     let zero_page_addr = layout::ZERO_PAGE_START;
     guest_mem

devices/Cargo.toml

@@ -15,3 +15,7 @@ vmm-sys-util = { git = "https://github.com/rust-vmm/vmm-sys-util" }
 
 [dev-dependencies]
 tempfile = "3.1.0"
+
+[features]
+default = ["acpi"]
+acpi = []

devices/src/lib.rs

@@ -19,11 +19,13 @@ extern crate vmm_sys_util;
 use std::fs::File;
 use std::{io, result};
 
+#[cfg(feature = "acpi")]
 mod acpi;
 mod bus;
 pub mod ioapic;
 pub mod legacy;
 
+#[cfg(feature = "acpi")]
 pub use self::acpi::AcpiShutdownDevice;
 pub use self::bus::{Bus, BusDevice, Error as BusError};
 

vmm/Cargo.toml

@@ -4,8 +4,12 @@ version = "0.1.0"
 authors = ["The Cloud Hypervisor Authors"]
 edition = "2018"
 
+[features]
+default = ["acpi"]
+acpi = ["acpi_tables"]
+
 [dependencies]
-acpi_tables = { path = "../acpi_tables" }
+acpi_tables = { path = "../acpi_tables", optional = true }
 arch = { path = "../arch" }
 devices = { path = "../devices" }
 epoll = "4.1.0"

vmm/src/vm.rs

@@ -619,6 +619,7 @@ struct DeviceManager {
     // i8042 device for i8042 reset
     i8042: Arc<Mutex<devices::legacy::I8042Device>>,
 
+    #[cfg(feature = "acpi")]
     // ACPI device for reboot/shutdwon
     acpi_device: Arc<Mutex<devices::AcpiShutdownDevice>>,
 
@@ -700,6 +701,8 @@ impl DeviceManager {
         let i8042 = Arc::new(Mutex::new(devices::legacy::I8042Device::new(
             reset_evt.try_clone().map_err(DeviceManagerError::EventFd)?,
         )));
+
+        #[cfg(feature = "acpi")]
         let acpi_device = Arc::new(Mutex::new(devices::AcpiShutdownDevice::new(
             exit_evt.try_clone().map_err(DeviceManagerError::EventFd)?,
             reset_evt.try_clone().map_err(DeviceManagerError::EventFd)?,
@@ -755,6 +758,7 @@ impl DeviceManager {
             serial,
             console_input: console,
             i8042,
+            #[cfg(feature = "acpi")]
             acpi_device,
             exit_evt,
             reset_evt,
@@ -1303,6 +1307,7 @@ impl DeviceManager {
             .insert(self.i8042.clone(), 0x61, 0x4)
             .map_err(Error::BusError)?;
 
+        #[cfg(feature = "acpi")]
         self.io_bus
             .insert(self.acpi_device.clone(), 0x3c0, 0x4)
             .map_err(Error::BusError)?;