blob: eccee1040d0ba3eb822e6bd46e334e960e6617d4 [file] [log] [blame]
// 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.
//! Handles IPC for controlling the main VM process.
//!
//! The VM Control IPC protocol is synchronous, meaning that each `VmRequest` sent over a connection
//! will receive a `VmResponse` for that request next time data is received over that connection.
//!
//! The wire message format is a little-endian C-struct of fixed size, along with a file descriptor
//! if the request type expects one.
use std::fmt::{self, Display};
use std::fs::File;
use std::io::{Seek, SeekFrom};
use std::os::unix::io::{AsRawFd, FromRawFd, RawFd};
use libc::{EINVAL, EIO, ENODEV};
use kvm::{IrqRoute, IrqSource, Vm};
use msg_socket::{MsgOnSocket, MsgReceiver, MsgResult, MsgSender, MsgSocket};
use resources::{Alloc, GpuMemoryDesc, MmioType, SystemAllocator};
use sys_util::{error, Error as SysError, EventFd, GuestAddress, MemoryMapping, MmapError, Result};
/// A file descriptor either borrowed or owned by this.
#[derive(Debug)]
pub enum MaybeOwnedFd {
/// Owned by this enum variant, and will be destructed automatically if not moved out.
Owned(File),
/// A file descriptor borrwed by this enum.
Borrowed(RawFd),
}
impl AsRawFd for MaybeOwnedFd {
fn as_raw_fd(&self) -> RawFd {
match self {
MaybeOwnedFd::Owned(f) => f.as_raw_fd(),
MaybeOwnedFd::Borrowed(fd) => *fd,
}
}
}
// When sent, it could be owned or borrowed. On the receiver end, it always owned.
impl MsgOnSocket for MaybeOwnedFd {
fn msg_size() -> usize {
0usize
}
fn max_fd_count() -> usize {
1usize
}
unsafe fn read_from_buffer(buffer: &[u8], fds: &[RawFd]) -> MsgResult<(Self, usize)> {
let (fd, size) = RawFd::read_from_buffer(buffer, fds)?;
let file = File::from_raw_fd(fd);
Ok((MaybeOwnedFd::Owned(file), size))
}
fn write_to_buffer(&self, buffer: &mut [u8], fds: &mut [RawFd]) -> MsgResult<usize> {
let fd = self.as_raw_fd();
fd.write_to_buffer(buffer, fds)
}
}
/// Mode of execution for the VM.
#[derive(Debug)]
pub enum VmRunMode {
/// The default run mode indicating the VCPUs are running.
Running,
/// Indicates that the VCPUs are suspending execution until the `Running` mode is set.
Suspending,
/// Indicates that the VM is exiting all processes.
Exiting,
}
impl Display for VmRunMode {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::VmRunMode::*;
match self {
Running => write!(f, "running"),
Suspending => write!(f, "suspending"),
Exiting => write!(f, "exiting"),
}
}
}
impl Default for VmRunMode {
fn default() -> Self {
VmRunMode::Running
}
}
/// The maximum number of devices that can be listed in one `UsbControlCommand`.
///
/// This value was set to be equal to `xhci_regs::MAX_PORTS` for convenience, but it is not
/// necessary for correctness. Importing that value directly would be overkill because it would
/// require adding a big dependency for a single const.
pub const USB_CONTROL_MAX_PORTS: usize = 16;
#[derive(MsgOnSocket, Debug)]
pub enum BalloonControlCommand {
/// Set the size of the VM's balloon.
Adjust { num_bytes: u64 },
}
#[derive(MsgOnSocket, Debug)]
pub enum DiskControlCommand {
/// Resize a disk to `new_size` in bytes.
Resize { new_size: u64 },
}
impl Display for DiskControlCommand {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::DiskControlCommand::*;
match self {
Resize { new_size } => write!(f, "disk_resize {}", new_size),
}
}
}
#[derive(MsgOnSocket, Debug)]
pub enum DiskControlResult {
Ok,
Err(SysError),
}
#[derive(MsgOnSocket, Debug)]
pub enum UsbControlCommand {
AttachDevice {
bus: u8,
addr: u8,
vid: u16,
pid: u16,
fd: Option<MaybeOwnedFd>,
},
DetachDevice {
port: u8,
},
ListDevice {
ports: [u8; USB_CONTROL_MAX_PORTS],
},
}
#[derive(MsgOnSocket, Copy, Clone, Debug, Default)]
pub struct UsbControlAttachedDevice {
pub port: u8,
pub vendor_id: u16,
pub product_id: u16,
}
impl UsbControlAttachedDevice {
fn valid(self) -> bool {
self.port != 0
}
}
#[derive(MsgOnSocket, Debug)]
pub enum UsbControlResult {
Ok { port: u8 },
NoAvailablePort,
NoSuchDevice,
NoSuchPort,
FailedToOpenDevice,
Devices([UsbControlAttachedDevice; USB_CONTROL_MAX_PORTS]),
}
impl Display for UsbControlResult {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::UsbControlResult::*;
match self {
Ok { port } => write!(f, "ok {}", port),
NoAvailablePort => write!(f, "no_available_port"),
NoSuchDevice => write!(f, "no_such_device"),
NoSuchPort => write!(f, "no_such_port"),
FailedToOpenDevice => write!(f, "failed_to_open_device"),
Devices(devices) => {
write!(f, "devices")?;
for d in devices.iter().filter(|d| d.valid()) {
write!(f, " {} {:04x} {:04x}", d.port, d.vendor_id, d.product_id)?;
}
std::result::Result::Ok(())
}
}
}
}
#[derive(MsgOnSocket, Debug)]
pub enum VmMemoryRequest {
/// Register shared memory represented by the given fd into guest address space. The response
/// variant is `VmResponse::RegisterMemory`.
RegisterMemory(MaybeOwnedFd, usize),
/// Similiar to `VmMemoryRequest::RegisterMemory`, but doesn't allocate new address space.
/// Useful for cases where the address space is already allocated (PCI regions).
RegisterMemoryAtAddress(Alloc, MaybeOwnedFd, usize, u64),
/// Unregister the given memory slot that was previously registereed with `RegisterMemory`.
UnregisterMemory(u32),
/// Allocate GPU buffer of a given size/format and register the memory into guest address space.
/// The response variant is `VmResponse::AllocateAndRegisterGpuMemory`
AllocateAndRegisterGpuMemory {
width: u32,
height: u32,
format: u32,
},
}
impl VmMemoryRequest {
/// Executes this request on the given Vm.
///
/// # Arguments
/// * `vm` - The `Vm` to perform the request on.
/// * `allocator` - Used to allocate addresses.
///
/// This does not return a result, instead encapsulating the success or failure in a
/// `VmMemoryResponse` with the intended purpose of sending the response back over the socket
/// that received this `VmMemoryResponse`.
pub fn execute(&self, vm: &mut Vm, sys_allocator: &mut SystemAllocator) -> VmMemoryResponse {
use self::VmMemoryRequest::*;
match *self {
RegisterMemory(ref fd, size) => {
match register_memory(vm, sys_allocator, fd, size, None) {
Ok((pfn, slot)) => VmMemoryResponse::RegisterMemory { pfn, slot },
Err(e) => VmMemoryResponse::Err(e),
}
}
RegisterMemoryAtAddress(alloc, ref fd, size, guest_addr) => {
match register_memory(vm, sys_allocator, fd, size, Some((alloc, guest_addr))) {
Ok((pfn, slot)) => VmMemoryResponse::RegisterMemory { pfn, slot },
Err(e) => VmMemoryResponse::Err(e),
}
}
UnregisterMemory(slot) => match vm.remove_mmio_memory(slot) {
Ok(_) => VmMemoryResponse::Ok,
Err(e) => VmMemoryResponse::Err(e),
},
AllocateAndRegisterGpuMemory {
width,
height,
format,
} => {
let (mut fd, desc) = match sys_allocator.gpu_memory_allocator() {
Some(gpu_allocator) => match gpu_allocator.allocate(width, height, format) {
Ok(v) => v,
Err(e) => return VmMemoryResponse::Err(e),
},
None => return VmMemoryResponse::Err(SysError::new(ENODEV)),
};
// Determine size of buffer using 0 byte seek from end. This is preferred over
// `stride * height` as it's not limited to packed pixel formats.
let size = match fd.seek(SeekFrom::End(0)) {
Ok(v) => v,
Err(e) => return VmMemoryResponse::Err(SysError::from(e)),
};
match register_memory(vm, sys_allocator, &fd, size as usize, None) {
Ok((pfn, slot)) => VmMemoryResponse::AllocateAndRegisterGpuMemory {
fd: MaybeOwnedFd::Owned(fd),
pfn,
slot,
desc,
},
Err(e) => VmMemoryResponse::Err(e),
}
}
}
}
}
#[derive(MsgOnSocket, Debug)]
pub enum VmMemoryResponse {
/// The request to register memory into guest address space was successfully done at page frame
/// number `pfn` and memory slot number `slot`.
RegisterMemory {
pfn: u64,
slot: u32,
},
/// The request to allocate and register GPU memory into guest address space was successfully
/// done at page frame number `pfn` and memory slot number `slot` for buffer with `desc`.
AllocateAndRegisterGpuMemory {
fd: MaybeOwnedFd,
pfn: u64,
slot: u32,
desc: GpuMemoryDesc,
},
Ok,
Err(SysError),
}
#[derive(MsgOnSocket, Debug)]
pub enum VmIrqRequest {
/// Allocate one gsi, and associate gsi to irqfd with register_irqfd()
AllocateOneMsi { irqfd: MaybeOwnedFd },
/// Add one msi route entry into kvm
AddMsiRoute {
gsi: u32,
msi_address: u64,
msi_data: u32,
},
}
impl VmIrqRequest {
/// Executes this request on the given Vm.
///
/// # Arguments
/// * `vm` - The `Vm` to perform the request on.
///
/// This does not return a result, instead encapsulating the success or failure in a
/// `VmIrqResponse` with the intended purpose of sending the response back over the socket
/// that received this `VmIrqResponse`.
pub fn execute(&self, vm: &mut Vm, sys_allocator: &mut SystemAllocator) -> VmIrqResponse {
use self::VmIrqRequest::*;
match *self {
AllocateOneMsi { ref irqfd } => {
if let Some(irq_num) = sys_allocator.allocate_irq() {
let evt = unsafe { EventFd::from_raw_fd(irqfd.as_raw_fd()) };
match vm.register_irqfd(&evt, irq_num) {
Ok(_) => VmIrqResponse::AllocateOneMsi { gsi: irq_num },
Err(e) => VmIrqResponse::Err(e),
}
} else {
VmIrqResponse::Err(SysError::new(EINVAL))
}
}
AddMsiRoute {
gsi,
msi_address,
msi_data,
} => {
let route = IrqRoute {
gsi,
source: IrqSource::Msi {
address: msi_address,
data: msi_data,
},
};
match vm.add_irq_route_entry(route) {
Ok(_) => VmIrqResponse::Ok,
Err(e) => VmIrqResponse::Err(e),
}
}
}
}
}
#[derive(MsgOnSocket, Debug)]
pub enum VmIrqResponse {
AllocateOneMsi { gsi: u32 },
Ok,
Err(SysError),
}
pub type BalloonControlRequestSocket = MsgSocket<BalloonControlCommand, ()>;
pub type BalloonControlResponseSocket = MsgSocket<(), BalloonControlCommand>;
pub type DiskControlRequestSocket = MsgSocket<DiskControlCommand, DiskControlResult>;
pub type DiskControlResponseSocket = MsgSocket<DiskControlResult, DiskControlCommand>;
pub type UsbControlSocket = MsgSocket<UsbControlCommand, UsbControlResult>;
pub type VmMemoryControlRequestSocket = MsgSocket<VmMemoryRequest, VmMemoryResponse>;
pub type VmMemoryControlResponseSocket = MsgSocket<VmMemoryResponse, VmMemoryRequest>;
pub type VmIrqRequestSocket = MsgSocket<VmIrqRequest, VmIrqResponse>;
pub type VmIrqResponseSocket = MsgSocket<VmIrqResponse, VmIrqRequest>;
pub type VmControlRequestSocket = MsgSocket<VmRequest, VmResponse>;
pub type VmControlResponseSocket = MsgSocket<VmResponse, VmRequest>;
/// A request to the main process to perform some operation on the VM.
///
/// Unless otherwise noted, each request should expect a `VmResponse::Ok` to be received on success.
#[derive(MsgOnSocket, Debug)]
pub enum VmRequest {
/// Break the VM's run loop and exit.
Exit,
/// Suspend the VM's VCPUs until resume.
Suspend,
/// Resume the VM's VCPUs that were previously suspended.
Resume,
/// Command for balloon driver.
BalloonCommand(BalloonControlCommand),
/// Send a command to a disk chosen by `disk_index`.
/// `disk_index` is a 0-based count of `--disk`, `--rwdisk`, and `-r` command-line options.
DiskCommand {
disk_index: usize,
command: DiskControlCommand,
},
/// Command to use controller.
UsbCommand(UsbControlCommand),
}
fn register_memory(
vm: &mut Vm,
allocator: &mut SystemAllocator,
fd: &dyn AsRawFd,
size: usize,
allocation: Option<(Alloc, u64)>,
) -> Result<(u64, u32)> {
let mmap = match MemoryMapping::from_fd(fd, size) {
Ok(v) => v,
Err(MmapError::SystemCallFailed(e)) => return Err(e),
_ => return Err(SysError::new(EINVAL)),
};
let addr = match allocation {
Some((Alloc::PciBar { bus, dev, bar }, address)) => {
match allocator
.mmio_allocator(MmioType::High)
.get(&Alloc::PciBar { bus, dev, bar })
{
Some((start_addr, length, _)) => {
let range = *start_addr..*start_addr + *length;
let end = address + (size as u64);
match (range.contains(&address), range.contains(&end)) {
(true, true) => address,
_ => return Err(SysError::new(EINVAL)),
}
}
None => return Err(SysError::new(EINVAL)),
}
}
None => {
let alloc = allocator.get_anon_alloc();
match allocator.mmio_allocator(MmioType::High).allocate(
size as u64,
alloc,
"vmcontrol_register_memory".to_string(),
) {
Ok(a) => a,
_ => return Err(SysError::new(EINVAL)),
}
}
_ => return Err(SysError::new(EINVAL)),
};
let slot = match vm.add_mmio_memory(GuestAddress(addr), mmap, false, false) {
Ok(v) => v,
Err(e) => return Err(e),
};
Ok((addr >> 12, slot))
}
impl VmRequest {
/// Executes this request on the given Vm and other mutable state.
///
/// This does not return a result, instead encapsulating the success or failure in a
/// `VmResponse` with the intended purpose of sending the response back over the socket that
/// received this `VmRequest`.
pub fn execute(
&self,
run_mode: &mut Option<VmRunMode>,
balloon_host_socket: &BalloonControlRequestSocket,
disk_host_sockets: &[DiskControlRequestSocket],
usb_control_socket: &UsbControlSocket,
) -> VmResponse {
match *self {
VmRequest::Exit => {
*run_mode = Some(VmRunMode::Exiting);
VmResponse::Ok
}
VmRequest::Suspend => {
*run_mode = Some(VmRunMode::Suspending);
VmResponse::Ok
}
VmRequest::Resume => {
*run_mode = Some(VmRunMode::Running);
VmResponse::Ok
}
VmRequest::BalloonCommand(ref command) => match balloon_host_socket.send(command) {
Ok(_) => VmResponse::Ok,
Err(_) => VmResponse::Err(SysError::last()),
},
VmRequest::DiskCommand {
disk_index,
ref command,
} => {
// Forward the request to the block device process via its control socket.
if let Some(sock) = disk_host_sockets.get(disk_index) {
if let Err(e) = sock.send(command) {
error!("disk socket send failed: {}", e);
VmResponse::Err(SysError::new(EINVAL))
} else {
match sock.recv() {
Ok(DiskControlResult::Ok) => VmResponse::Ok,
Ok(DiskControlResult::Err(e)) => VmResponse::Err(e),
Err(e) => {
error!("disk socket recv failed: {}", e);
VmResponse::Err(SysError::new(EINVAL))
}
}
}
} else {
VmResponse::Err(SysError::new(ENODEV))
}
}
VmRequest::UsbCommand(ref cmd) => {
let res = usb_control_socket.send(cmd);
if let Err(e) = res {
error!("fail to send command to usb control socket: {}", e);
return VmResponse::Err(SysError::new(EIO));
}
match usb_control_socket.recv() {
Ok(response) => VmResponse::UsbResponse(response),
Err(e) => {
error!("fail to recv command from usb control socket: {}", e);
VmResponse::Err(SysError::new(EIO))
}
}
}
}
}
}
/// Indication of success or failure of a `VmRequest`.
///
/// Success is usually indicated `VmResponse::Ok` unless there is data associated with the response.
#[derive(MsgOnSocket, Debug)]
pub enum VmResponse {
/// Indicates the request was executed successfully.
Ok,
/// Indicates the request encountered some error during execution.
Err(SysError),
/// The request to register memory into guest address space was successfully done at page frame
/// number `pfn` and memory slot number `slot`.
RegisterMemory { pfn: u64, slot: u32 },
/// The request to allocate and register GPU memory into guest address space was successfully
/// done at page frame number `pfn` and memory slot number `slot` for buffer with `desc`.
AllocateAndRegisterGpuMemory {
fd: MaybeOwnedFd,
pfn: u64,
slot: u32,
desc: GpuMemoryDesc,
},
/// Results of usb control commands.
UsbResponse(UsbControlResult),
}
impl Display for VmResponse {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::VmResponse::*;
match self {
Ok => write!(f, "ok"),
Err(e) => write!(f, "error: {}", e),
RegisterMemory { pfn, slot } => write!(
f,
"memory registered to page frame number {:#x} and memory slot {}",
pfn, slot
),
AllocateAndRegisterGpuMemory { pfn, slot, .. } => write!(
f,
"gpu memory allocated and registered to page frame number {:#x} and memory slot {}",
pfn, slot
),
UsbResponse(result) => write!(f, "usb control request get result {:?}", result),
}
}
}