vm-virtio: Enable the vmm support for virtio-console

To use the implemented virtio console device, the users can select one
of the three options ("off", "tty" or "file=/path/to/the/file") with
the command line argument "--console". By default, the console is
enabled as a device named "hvc0" (option: tty). When "off" option is
used, the console device is not added to the VM configuration at all.

Signed-off-by: A K M Fazla Mehrab <fazla.mehrab.akm@intel.com>

src/main.rs

@@ -92,6 +92,12 @@ fn main() {
             Arg::with_name("serial")
                 .long("serial")
                 .help("Control serial port: off|tty|file=/path/to/a/file")
+                .default_value("off"),
+        )
+        .arg(
+            Arg::with_name("console")
+                .long("console")
+                .help("Control (virtio) console: off|tty|file=/path/to/a/file")
                 .default_value("tty"),
         )
         .get_matches();
@@ -109,6 +115,7 @@ fn main() {
 
     let disks: Option<Vec<&str>> = cmd_arguments.values_of("disk").map(|x| x.collect());
     let net: Option<Vec<&str>> = cmd_arguments.values_of("net").map(|x| x.collect());
+    let console = cmd_arguments.value_of("console").unwrap();
     let fs: Option<Vec<&str>> = cmd_arguments.values_of("fs").map(|x| x.collect());
     let pmem: Option<Vec<&str>> = cmd_arguments.values_of("pmem").map(|x| x.collect());
 
@@ -123,6 +130,7 @@ fn main() {
         fs,
         pmem,
         serial,
+        console,
     }) {
         Ok(config) => config,
         Err(e) => {

vmm/src/config.rs

@@ -50,8 +50,10 @@ pub enum Error<'a> {
     ParsePmemFileParam,
     /// Failed parsing size parameter.
     ParseSizeParam(std::num::ParseIntError),
-    /// Failed parsing serial parameter.
+    /// Failed parsing console parameter.
-    ParseSerialParam,
+    ParseConsoleParam,
+    /// Both console and serial are tty.
+    ParseTTYParam,
 }
 pub type Result<'a, T> = result::Result<T, Error<'a>>;
 
@@ -66,6 +68,7 @@ pub struct VmParams<'a> {
     pub fs: Option<Vec<&'a str>>,
     pub pmem: Option<Vec<&'a str>>,
     pub serial: &'a str,
+    pub console: &'a str,
 }
 
 fn parse_size(size: &str) -> Result<u64> {
@@ -342,36 +345,36 @@ impl<'a> PmemConfig<'a> {
 }
 
 #[derive(PartialEq)]
-pub enum SerialOutputMode {
+pub enum ConsoleOutputMode {
     Off,
     Tty,
     File,
 }
 
-pub struct SerialConfig<'a> {
+pub struct ConsoleConfig<'a> {
     pub file: Option<&'a Path>,
-    pub mode: SerialOutputMode,
+    pub mode: ConsoleOutputMode,
 }
 
-impl<'a> SerialConfig<'a> {
+impl<'a> ConsoleConfig<'a> {
     pub fn parse(param: &'a str) -> Result<Self> {
         if param == "off" {
             Ok(Self {
-                mode: SerialOutputMode::Off,
+                mode: ConsoleOutputMode::Off,
                 file: None,
             })
         } else if param == "tty" {
             Ok(Self {
-                mode: SerialOutputMode::Tty,
+                mode: ConsoleOutputMode::Tty,
                 file: None,
             })
         } else if param.starts_with("file=") {
             Ok(Self {
-                mode: SerialOutputMode::File,
+                mode: ConsoleOutputMode::File,
                 file: Some(Path::new(&param[5..])),
             })
         } else {
-            Err(Error::ParseSerialParam)
+            Err(Error::ParseConsoleParam)
         }
     }
 }
@@ -386,7 +389,8 @@ pub struct VmConfig<'a> {
     pub rng: RngConfig<'a>,
     pub fs: Option<Vec<FsConfig<'a>>>,
     pub pmem: Option<Vec<PmemConfig<'a>>>,
-    pub serial: SerialConfig<'a>,
+    pub serial: ConsoleConfig<'a>,
+    pub console: ConsoleConfig<'a>,
 }
 
 impl<'a> VmConfig<'a> {
@@ -427,6 +431,12 @@ impl<'a> VmConfig<'a> {
             pmem = Some(pmem_config_list);
         }
 
+        let console = ConsoleConfig::parse(vm_params.console)?;
+        let serial = ConsoleConfig::parse(vm_params.serial)?;
+        if console.mode == ConsoleOutputMode::Tty && serial.mode == ConsoleOutputMode::Tty {
+            return Err(Error::ParseTTYParam);
+        }
+
         Ok(VmConfig {
             cpus: CpusConfig::parse(vm_params.cpus)?,
             memory: MemoryConfig::parse(vm_params.memory)?,
@@ -437,7 +447,8 @@ impl<'a> VmConfig<'a> {
             rng: RngConfig::parse(vm_params.rng)?,
             fs,
             pmem,
-            serial: SerialConfig::parse(vm_params.serial)?,
+            serial,
+            console,
         })
     }
 }

vmm/src/vm.rs

@@ -21,7 +21,7 @@ extern crate vm_memory;
 extern crate vm_virtio;
 extern crate vmm_sys_util;
 
-use crate::config::{SerialOutputMode, VmConfig};
+use crate::config::{ConsoleOutputMode, VmConfig};
 use arch::RegionType;
 use devices::ioapic;
 use kvm_bindings::{
@@ -142,6 +142,9 @@ pub enum Error {
     /// Write to the serial console failed.
     Serial(vmm_sys_util::Error),
 
+    /// Write to the virtio console failed.
+    Console(vmm_sys_util::Error),
+
     /// Cannot setup terminal in raw mode.
     SetTerminalRaw(vmm_sys_util::Error),
 
@@ -189,6 +192,9 @@ pub enum DeviceManagerError {
     /// Cannot create virtio-net device
     CreateVirtioNet(vm_virtio::net::Error),
 
+    /// Cannot create virtio-console device
+    CreateVirtioConsole(io::Error),
+
     /// Cannot create virtio-rng device
     CreateVirtioRng(io::Error),
 
@@ -236,6 +242,9 @@ pub enum DeviceManagerError {
 
     /// Error creating serial output file
     SerialOutputFileOpen(io::Error),
+
+    /// Error creating console output file
+    ConsoleOutputFileOpen(io::Error),
 }
 pub type DeviceManagerResult<T> = result::Result<T, DeviceManagerError>;
 
@@ -483,6 +492,7 @@ struct DeviceManager {
 
     // Serial port on 0x3f8
     serial: Option<Arc<Mutex<devices::legacy::Serial>>>,
+    console: Option<Arc<vm_virtio::ConsoleInput>>,
 
     // i8042 device for exit
     i8042: Arc<Mutex<devices::legacy::I8042Device>>,
@@ -525,12 +535,12 @@ impl DeviceManager {
         };
 
         let serial_writer: Option<Box<io::Write + Send>> = match vm_cfg.serial.mode {
-            SerialOutputMode::File => Some(Box::new(
+            ConsoleOutputMode::File => Some(Box::new(
                 File::create(vm_cfg.serial.file.unwrap())
                     .map_err(DeviceManagerError::SerialOutputFileOpen)?,
             )),
-            SerialOutputMode::Tty => Some(Box::new(stdout())),
+            ConsoleOutputMode::Tty => Some(Box::new(stdout())),
-            SerialOutputMode::Off => None,
+            ConsoleOutputMode::Off => None,
         };
         let serial = if serial_writer.is_some() {
             // Serial is tied to IRQ #4
@@ -632,6 +642,31 @@ impl DeviceManager {
             }
         }
 
+        let console_writer: Option<Box<io::Write + Send>> = match vm_cfg.console.mode {
+            ConsoleOutputMode::File => Some(Box::new(
+                File::create(vm_cfg.console.file.unwrap())
+                    .map_err(DeviceManagerError::ConsoleOutputFileOpen)?,
+            )),
+            ConsoleOutputMode::Tty => Some(Box::new(stdout())),
+            ConsoleOutputMode::Off => None,
+        };
+        let console = if console_writer.is_some() {
+            let (virtio_console_device, console) = vm_virtio::Console::new(console_writer)
+                .map_err(DeviceManagerError::CreateVirtioConsole)?;
+            DeviceManager::add_virtio_pci_device(
+                Box::new(virtio_console_device),
+                memory.clone(),
+                allocator,
+                vm_fd,
+                &mut pci,
+                &mut buses,
+                &interrupt_info,
+            )?;
+            Some(console)
+        } else {
+            None
+        };
+
         // Add virtio-rng if required
         if let Some(rng_path) = vm_cfg.rng.src.to_str() {
             let virtio_rng_device =
@@ -745,6 +780,7 @@ impl DeviceManager {
             io_bus,
             mmio_bus,
             serial,
+            console,
             i8042,
             exit_evt,
             ioapic,
@@ -1253,7 +1289,7 @@ impl<'a> Vm<'a> {
         let mut events = vec![epoll::Event::new(epoll::Events::empty(), 0); EPOLL_EVENTS_LEN];
         let epoll_fd = self.epoll.as_raw_fd();
 
-        if self.devices.serial.is_some() && self.on_tty {
+        if (self.devices.serial.is_some() || self.devices.console.is_some()) && self.on_tty {
             io::stdin()
                 .lock()
                 .set_raw_mode()
@@ -1276,13 +1312,13 @@ impl<'a> Vm<'a> {
                             break 'outer;
                         }
                         EpollDispatch::Stdin => {
-                            if self.devices.serial.is_some() {
                             let mut out = [0u8; 64];
                             let count = io::stdin()
                                 .lock()
                                 .read_raw(&mut out)
                                 .map_err(Error::Serial)?;
 
+                            if self.devices.serial.is_some() {
                                 self.devices
                                     .serial
                                     .as_ref()
@@ -1292,6 +1328,14 @@ impl<'a> Vm<'a> {
                                     .queue_input_bytes(&out[..count])
                                     .map_err(Error::Serial)?;
                             }
+
+                            if self.devices.console.is_some() {
+                                self.devices
+                                    .console
+                                    .as_ref()
+                                    .unwrap()
+                                    .queue_input_bytes(&out[..count]);
+                            }
                         }
                     }
                 }