crosvm: Add crosvm main program

This program is used to boot a 64-bit kernel elf. It has support for
basic devices that are exposed to the kernel, including a block device.

TEST=cargo test;
     cargo run -- -m 512 -c 4 -d rootfs.squashfs -u -p "init=/bin/bash" vmlinux
BUG=chromium:712319

Change-Id: I25a8349a4624d8643fefe2ad70e517fe03b16b8c
Reviewed-on: https://chromium-review.googlesource.com/514417
Commit-Ready: Zach Reizner <zachr@chromium.org>
Tested-by: Zach Reizner <zachr@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

1 files changed, 542 insertions, 0 deletions

diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..1e1d601
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,542 @@
+// Copyright 2017 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+//! Runs a virtual machine under KVM
+
+extern crate clap;
+extern crate libc;
+extern crate kvm;
+extern crate x86_64;
+extern crate kernel_loader;
+extern crate byteorder;
+#[macro_use] extern crate sys_util;
+
+use std::ffi::{CString, CStr};
+use std::fmt;
+use std::fs::File;
+use std::io::{stdin, stdout};
+use std::string::String;
+use std::sync::{Arc, Mutex, Barrier};
+use std::thread::{spawn, JoinHandle};
+
+use clap::{Arg, App, SubCommand};
+
+use kvm::*;
+use sys_util::{GuestAddress, GuestMemory, EventFd, Terminal, Poller, Pollable,
+               register_signal_handler, Killable};
+
+pub mod hw;
+pub mod kernel_cmdline;
+pub mod control_socket;
+
+use control_socket::*;
+
+enum Error {
+    Socket(std::io::Error),
+    Disk(std::io::Error),
+    BlockDeviceNew(sys_util::Error),
+    Cmdline(kernel_cmdline::Error),
+    ProxyDeviceCreation(std::io::Error),
+    RegisterIoevent(sys_util::Error),
+    RegisterIrqfd(sys_util::Error),
+    KernelLoader(kernel_loader::Error),
+    ConfigureSystem(x86_64::Error),
+    EventFd(sys_util::Error),
+    Kvm(sys_util::Error),
+    Vm(sys_util::Error),
+    Vcpu(sys_util::Error),
+    Sys(sys_util::Error),
+}
+
+impl std::convert::From<kernel_loader::Error> for Error {
+    fn from(e: kernel_loader::Error) -> Error {
+        Error::KernelLoader(e)
+    }
+}
+
+impl std::convert::From<x86_64::Error> for Error {
+    fn from(e: x86_64::Error) -> Error {
+        Error::ConfigureSystem(e)
+    }
+}
+
+impl std::convert::From<sys_util::Error> for Error {
+    fn from(e: sys_util::Error) -> Error {
+        Error::Sys(e)
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            &Error::Socket(ref e) => write!(f, "failed to create socket: {}", e),
+            &Error::Disk(ref e) => write!(f, "failed to load disk image: {}", e),
+            &Error::BlockDeviceNew(ref e) => write!(f, "failed to create block device: {:?}", e),
+            &Error::Cmdline(ref e) => write!(f, "the given kernel command line was invalid: {}", e),
+            &Error::ProxyDeviceCreation(ref e) => write!(f, "failed to create proxy device: {}", e),
+            &Error::RegisterIoevent(ref e) => write!(f, "error registering ioevent: {:?}", e),
+            &Error::RegisterIrqfd(ref e) => write!(f, "error registering irqfd: {:?}", e),
+            &Error::KernelLoader(ref e) => write!(f, "error loading kernel: {:?}", e),
+            &Error::ConfigureSystem(ref e) => write!(f, "error configuring system: {:?}", e),
+            &Error::EventFd(ref e) => write!(f, "error creating EventFd: {:?}", e),
+            &Error::Kvm(ref e) => write!(f, "error creating Kvm: {:?}", e),
+            &Error::Vm(ref e) => write!(f, "error creating Vm: {:?}", e),
+            &Error::Vcpu(ref e) => write!(f, "error creating Vcpu: {:?}", e),
+            &Error::Sys(ref e) => write!(f, "error with system call: {:?}", e),
+        }
+    }
+}
+
+type Result<T> = std::result::Result<T, Error>;
+
+struct Config {
+    disk_path: Option<String>,
+    vcpu_count: Option<u32>,
+    memory: Option<usize>,
+    kernel_image: File,
+    params: Option<String>,
+    socket_path: Option<String>,
+    multiprocess: bool,
+    warn_unknown_ports: bool,
+}
+
+enum VmRequest {
+    RegisterIoevent(EventFd, IoeventAddress, u32),
+    RegisterIrqfd(EventFd, u32),
+}
+
+const KERNEL_START_OFFSET: usize = 0x200000;
+const CMDLINE_OFFSET: usize = 0x20000;
+const CMDLINE_MAX_SIZE: usize = KERNEL_START_OFFSET - CMDLINE_OFFSET;
+
+fn run_config(cfg: Config) -> Result<()> {
+    let socket = if let Some(ref socket_path) = cfg.socket_path {
+        Some(ControlSocketRecv::new(socket_path)
+                 .map_err(|e| Error::Socket(e))?)
+    } else {
+        None
+    };
+
+    let mem_size = cfg.memory.unwrap_or(256) << 20;
+    let guest_mem =
+        GuestMemory::new(&x86_64::arch_memory_regions(mem_size)).expect("new mmap failed");
+
+    let mut cmdline = kernel_cmdline::Cmdline::new(CMDLINE_MAX_SIZE);
+    cmdline
+        .insert_str("console=ttyS0 noapic noacpi reboot=k panic=1 pci=off")
+        .unwrap();
+
+    let mut vm_requests = Vec::new();
+
+    let mut bus = hw::Bus::new();
+
+    let mmio_len = 0x1000;
+    let mut mmio_base: u64 = 0xd0000000;
+    let mut irq: u32 = 5;
+
+    if let Some(ref disk_path) = cfg.disk_path {
+        let disk_image = File::open(disk_path).map_err(|e| Error::Disk(e))?;
+
+        let block_box = Box::new(hw::virtio::Block::new(disk_image)
+                                     .map_err(|e| Error::BlockDeviceNew(e))?);
+        let block_mmio = hw::virtio::MmioDevice::new(guest_mem.clone(), block_box)?;
+        for (i, queue_evt) in block_mmio.queue_evts().iter().enumerate() {
+            let io_addr = IoeventAddress::Mmio(mmio_base + hw::virtio::NOITFY_REG_OFFSET as u64);
+            vm_requests.push(VmRequest::RegisterIoevent(queue_evt.try_clone()?, io_addr, i as u32));
+        }
+
+        if let Some(interrupt_evt) = block_mmio.interrupt_evt() {
+            vm_requests.push(VmRequest::RegisterIrqfd(interrupt_evt.try_clone()?, irq));
+        }
+
+        if cfg.multiprocess {
+            bus.insert(Arc::new(Mutex::new(hw::ProxyDevice::new(block_mmio).unwrap())),
+                        mmio_base,
+                        mmio_len)
+                .unwrap();
+        } else {
+            bus.insert(Arc::new(Mutex::new(block_mmio)), mmio_base, mmio_len)
+                .unwrap();
+        }
+
+        cmdline
+            .insert("virtio_mmio.device",
+                    &format!("4K@0x{:08x}:{}", mmio_base, irq))
+            .map_err(Error::Cmdline)?;
+        cmdline
+            .insert("root", "/dev/vda")
+            .map_err(Error::Cmdline)?;
+        mmio_base += mmio_len;
+        irq += 1;
+    }
+
+    if let Some(params) = cfg.params {
+        cmdline
+            .insert_str(params)
+            .map_err(|e| Error::Cmdline(e))?;
+    }
+
+    run_kvm(vm_requests,
+            cfg.kernel_image,
+            &CString::new(cmdline).unwrap(),
+            cfg.vcpu_count.unwrap_or(1),
+            guest_mem,
+            bus,
+            socket,
+            cfg.warn_unknown_ports)
+}
+
+fn run_kvm(requests: Vec<VmRequest>,
+           mut kernel_image: File,
+           cmdline: &CStr,
+           vcpu_count: u32,
+           guest_mem: GuestMemory,
+           mmio_bus: hw::Bus,
+           control_socket: Option<ControlSocketRecv>,
+           warn_unknown_ports: bool)
+           -> Result<()> {
+    let kvm = Kvm::new().map_err(Error::Kvm)?;
+    let tss_addr = GuestAddress(0xfffbd000);
+    let kernel_start_addr = GuestAddress(KERNEL_START_OFFSET);
+    let cmdline_addr = GuestAddress(CMDLINE_OFFSET);
+
+    let vm = Vm::new(&kvm, guest_mem).map_err(Error::Vm)?;
+    vm.set_tss_addr(tss_addr).expect("set tss addr failed");
+    vm.create_pit().expect("create pit failed");
+    vm.create_irq_chip().expect("create irq chip failed");
+
+    for request in requests {
+        match request {
+            VmRequest::RegisterIoevent(evt, addr, datamatch) => {
+                vm.register_ioevent(&evt, addr, datamatch)
+                    .map_err(Error::RegisterIoevent)?
+            }
+            VmRequest::RegisterIrqfd(evt, irq) => {
+                vm.register_irqfd(&evt, irq)
+                    .map_err(Error::RegisterIrqfd)?
+            }
+        }
+    }
+
+    kernel_loader::load_kernel(vm.get_memory(), kernel_start_addr, &mut kernel_image)?;
+    kernel_loader::load_cmdline(vm.get_memory(), cmdline_addr, cmdline)?;
+    x86_64::configure_system(vm.get_memory(),
+                             kernel_start_addr,
+                             cmdline_addr,
+                             cmdline.to_bytes().len() + 1,
+                             vcpu_count as u8)?;
+
+    let mut io_bus = hw::Bus::new();
+
+    let exit_evt = EventFd::new().expect("failed to create exit eventfd");
+
+    struct NoDevice;
+    impl hw::BusDevice for NoDevice {}
+
+    let com_evt_1_3 = EventFd::new().map_err(Error::EventFd)?;
+    let com_evt_2_4 = EventFd::new().map_err(Error::EventFd)?;
+    let stdio_serial =
+        Arc::new(Mutex::new(hw::Serial::new_out(com_evt_1_3.try_clone().map_err(Error::EventFd)?,
+                                                Box::new(stdout()))));
+    let nul_device = Arc::new(Mutex::new(NoDevice));
+    io_bus.insert(stdio_serial.clone(), 0x3f8, 0x8).unwrap();
+    io_bus
+        .insert(Arc::new(Mutex::new(hw::Serial::new_sink(com_evt_2_4
+                                                             .try_clone()
+                                                             .map_err(Error::EventFd)?))),
+                0x2f8,
+                0x8)
+        .unwrap();
+    io_bus
+        .insert(Arc::new(Mutex::new(hw::Serial::new_sink(com_evt_1_3
+                                                             .try_clone()
+                                                             .map_err(Error::EventFd)?))),
+                0x3e8,
+                0x8)
+        .unwrap();
+    io_bus
+        .insert(Arc::new(Mutex::new(hw::Serial::new_sink(com_evt_2_4
+                                                             .try_clone()
+                                                             .map_err(Error::EventFd)?))),
+                0x2e8,
+                0x8)
+        .unwrap();
+    io_bus
+        .insert(Arc::new(Mutex::new(hw::Cmos::new())), 0x70, 0x2)
+        .unwrap();
+    io_bus
+        .insert(Arc::new(Mutex::new(hw::I8042Device::new(exit_evt
+                                                             .try_clone()
+                                                             .map_err(Error::EventFd)?))),
+                0x061,
+                0x4)
+        .unwrap();
+    io_bus.insert(nul_device.clone(), 0x040, 0x8).unwrap(); // ignore pit
+    io_bus.insert(nul_device.clone(), 0x0ed, 0x1).unwrap(); // most likely this one does nothing
+    io_bus.insert(nul_device.clone(), 0x0f0, 0x2).unwrap(); // ignore fpu
+    io_bus.insert(nul_device.clone(), 0xcf8, 0x8).unwrap(); // ignore pci
+
+    vm.register_irqfd(&com_evt_1_3, 4)
+        .map_err(Error::RegisterIrqfd)?;
+    vm.register_irqfd(&com_evt_2_4, 3)
+        .map_err(Error::RegisterIrqfd)?;
+
+    let mut vcpu_handles = Vec::with_capacity(vcpu_count as usize);
+    let vcpu_thread_barrier = Arc::new(Barrier::new((vcpu_count + 1) as usize));
+    for cpu_id in 0..vcpu_count {
+        let mmio_bus = mmio_bus.clone();
+        let io_bus = io_bus.clone();
+        let vcpu_thread_barrier = vcpu_thread_barrier.clone();
+        let vcpu_exit_evt = exit_evt.try_clone().map_err(Error::EventFd)?;
+        let vcpu = Vcpu::new(cpu_id as u64, &kvm, &vm).map_err(Error::Vcpu)?;
+        x86_64::configure_vcpu(vm.get_memory(),
+                               kernel_start_addr,
+                               &kvm,
+                               &vcpu,
+                               cpu_id as u64,
+                               vcpu_count as u64)?;
+        vcpu_handles.push(spawn(move || {
+            unsafe {
+                extern "C" fn handle_signal() {}
+                // Our signal handler does nothing and is trivially async signal safe.
+                register_signal_handler(0, handle_signal)
+                    .expect("failed to register vcpu signal handler");
+            }
+
+            vcpu_thread_barrier.wait();
+            loop {
+                let run_res = vcpu.run();
+                match run_res {
+                    Ok(run) => {
+                        match run {
+                            VcpuExit::IoIn(addr, data) => {
+                                if !io_bus.read(addr as u64, data) && warn_unknown_ports {
+                                    println!("warning: unhandled I/O port {}-bit read at 0x{:03x}",
+                                             data.len() << 3,
+                                             addr);
+                                }
+                            }
+
+                            VcpuExit::IoOut(addr, data) => {
+                                if !io_bus.write(addr as u64, data) && warn_unknown_ports {
+                                    println!("warning: unhandled I/O port {}-bit write at 0x{:03x}",
+                                             data.len() << 3,
+                                             addr);
+                                }
+                            }
+
+                            VcpuExit::MmioRead(addr, data) => {
+                                if !mmio_bus.read(addr, data) && warn_unknown_ports {
+                                    println!("warning: unhandled mmio {}-bit read at 0x{:08x}",
+                                             data.len() << 3,
+                                             addr);
+                                }
+                            }
+
+                            VcpuExit::MmioWrite(addr, data) => {
+                                if !mmio_bus.write(addr, data) && warn_unknown_ports {
+                                    println!("warning: unhandled mmio {}-bit write at 0x{:08x}",
+                                             data.len() << 3,
+                                             addr);
+                                }
+                            }
+
+                            VcpuExit::Hlt => break,
+                            VcpuExit::Shutdown => break,
+                            r => println!("unexpected vcpu exit: {:?}", r),
+                        }
+                    }
+                    Err(e) => {
+                        if e.errno() != libc::EAGAIN {
+                            break;
+                        }
+                    }
+                }
+            }
+            vcpu_exit_evt
+                .write(1)
+                .expect("failed to signal vcpu exit eventfd");
+        }));
+    }
+
+    vcpu_thread_barrier.wait();
+
+    run_control(control_socket, stdio_serial, exit_evt, vcpu_handles)
+}
+
+fn run_control(control_socket: Option<ControlSocketRecv>,
+               stdio_serial: Arc<Mutex<hw::Serial>>,
+               exit_evt: EventFd,
+               vcpu_handles: Vec<JoinHandle<()>>)
+               -> Result<()> {
+    const EXIT: u32 = 1;
+    const STDIN: u32 = 2;
+    const CONTROL: u32 = 3;
+
+    let stdin_handle = stdin();
+    let stdin_lock = stdin_handle.lock();
+    stdin_lock
+        .set_raw_mode()
+        .expect("failed to set terminal raw mode");
+
+    let mut pollables = Vec::new();
+    pollables.push((EXIT, &exit_evt as &Pollable));
+    pollables.push((STDIN, &stdin_lock as &Pollable));
+    if let Some(socket) = control_socket.as_ref() {
+        pollables.push((CONTROL, socket as &Pollable));
+    }
+
+    let mut poller = Poller::new(3);
+
+    'poll: loop {
+        let poll_res = {
+            match poller.poll(&pollables[..]) {
+                Ok(v) => v,
+                Err(e) => {
+                    println!("failed to poll: {:?}", e);
+                    break;
+                }
+            }
+        };
+        for i in poll_res {
+            match *i {
+                EXIT => {
+                    println!("vcpu requested shutdown");
+                    break 'poll;
+                }
+                STDIN => {
+                    let mut out = [0u8; 64];
+                    let count = stdin_lock.read_raw(&mut out[..]).unwrap_or_default();
+                    if count != 0 {
+                        stdio_serial
+                            .lock()
+                            .unwrap()
+                            .queue_input_bytes(&out[..count])
+                            .expect("failed to queue bytes into serial port");
+                    }
+                }
+                CONTROL if control_socket.is_some() => {
+                    if let Some(socket) = control_socket.as_ref() {
+                        match socket.recv().unwrap() {
+                            Command::Stop => {
+                                println!("control socket requested shutdown");
+                                break 'poll;
+                            }
+                            _ => {}
+                        }
+                    }
+                }
+                _ => {}
+            }
+        }
+    }
+
+    for handle in vcpu_handles {
+        match handle.kill(0) {
+            Ok(_) => {
+                if let Err(e) = handle.join() {
+                    println!("failed to join vcpu thread: {:?}", e);
+                }
+            }
+            Err(e) => println!("failed to kill vcpu thread: {:?}", e),
+        }
+    }
+
+    stdin_lock
+        .set_canon_mode()
+        .expect("failed to restore canonical mode for terminal");
+
+    Ok(())
+}
+
+fn main() {
+    let matches = App::new("crosvm")
+        .version("0.1.0")
+        .author("The Chromium OS Authors")
+        .about("Runs a virtual machine under KVM")
+        .subcommand(SubCommand::with_name("stop").arg(Arg::with_name("socket")
+                                                          .required(true)
+                                                          .multiple(true)
+                                                          .index(1)
+                                                          .value_name("PATH")
+                                                          .help("path of the control sockets")))
+        .subcommand(SubCommand::with_name("run")
+                        .arg(Arg::with_name("disk")
+                                 .short("d")
+                                 .long("disk")
+                                 .value_name("FILE")
+                                 .help("rootfs disk image")
+                                 .takes_value(true))
+                        .arg(Arg::with_name("cpus")
+                                 .short("c")
+                                 .long("cpus")
+                                 .value_name("N")
+                                 .help("number of VCPUs (WARNING: CURRENTLY UNUSED)")
+                                 .takes_value(true))
+                        .arg(Arg::with_name("memory")
+                                 .short("m")
+                                 .long("mem")
+                                 .value_name("N")
+                                 .help("amount of guest memory in MiB")
+                                 .takes_value(true))
+                        .arg(Arg::with_name("params")
+                                 .short("p")
+                                 .long("params")
+                                 .value_name("params")
+                                 .help("extra kernel command line arguments")
+                                 .takes_value(true))
+                        .arg(Arg::with_name("multiprocess")
+                                 .short("u")
+                                 .long("multiprocess")
+                                 .help("run the devices in a child process"))
+                        .arg(Arg::with_name("socket")
+                                 .short("s")
+                                 .long("socket")
+                                 .value_name("PATH")
+                                 .help("Path to put the control socket. If PATH is a directory, a name will be generated.")
+                                 .takes_value(true))
+                        .arg(Arg::with_name("warn-unknown-ports")
+                                 .long("warn-unknown-ports")
+                                 .help("warn when an the VM uses an unknown port"))
+                        .arg(Arg::with_name("KERNEL")
+                                 .required(true)
+                                 .index(1)
+                                 .help("bzImage of kernel to run")))
+        .get_matches();
+
+    match matches.subcommand() {
+        ("stop", Some(matches)) => {
+            for socket_path in matches.values_of("socket").unwrap() {
+                let res = match ControlSocketSend::new(socket_path) {
+                    Ok(s) => s.send(&Command::Stop),
+                    Err(e) => Err(e),
+                };
+                if let Err(e) = res {
+                    println!("failed to send stop command to socket at '{}': {}",
+                             socket_path,
+                             e);
+                }
+            }
+        }
+        ("run", Some(matches)) => {
+            let config = Config {
+                disk_path: matches.value_of("disk").map(|s| s.to_string()),
+                vcpu_count: matches.value_of("cpus").and_then(|v| v.parse().ok()),
+                memory: matches.value_of("memory").and_then(|v| v.parse().ok()),
+                kernel_image: File::open(matches.value_of("KERNEL").unwrap())
+                    .expect("Expected kernel image path to be valid"),
+                params: matches.value_of("params").map(|s| s.to_string()),
+                multiprocess: matches.is_present("multiprocess"),
+                socket_path: matches.value_of("socket").map(|s| s.to_string()),
+                warn_unknown_ports: matches.is_present("warn-unknown-ports"),
+            };
+
+            match run_config(config) {
+                Ok(_) => println!("crosvm has exited normally"),
+                Err(e) => println!("{}", e),
+            }
+        }
+        _ => {}
+    }
+}