cloud-hypervisor/vmm/src/vm_config.rs

// Copyright © 2022 Intel Corporation
//
// SPDX-License-Identifier: Apache-2.0
//
use std::net::IpAddr;
use std::path::{Path, PathBuf};
#[cfg(feature = "fw_cfg")]
use std::str::FromStr;
use std::{fs, result};

use net_util::MacAddr;
use serde::{Deserialize, Serialize};
use thiserror::Error;
use virtio_devices::RateLimiterConfig;

use crate::Landlock;
use crate::landlock::LandlockError;

pub type LandlockResult<T> = result::Result<T, LandlockError>;

/// Trait to apply Landlock on VmConfig elements
pub(crate) trait ApplyLandlock {
    /// Apply Landlock rules to file paths
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()>;
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct CpuAffinity {
    pub vcpu: u32,
    pub host_cpus: Vec<usize>,
}

#[derive(Clone, Debug, Default, PartialEq, Eq, Deserialize, Serialize)]
pub struct CpuFeatures {
    #[cfg(target_arch = "x86_64")]
    #[serde(default)]
    pub amx: bool,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct CpuTopology {
    pub threads_per_core: u16,
    pub cores_per_die: u16,
    pub dies_per_package: u16,
    pub packages: u16,
}

// When booting with PVH boot the maximum physical addressable size
// is a 46 bit address space even when the host supports with 5-level
// paging.
pub const DEFAULT_MAX_PHYS_BITS: u8 = 46;

pub fn default_cpuconfig_max_phys_bits() -> u8 {
    DEFAULT_MAX_PHYS_BITS
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct CpusConfig {
    pub boot_vcpus: u32,
    pub max_vcpus: u32,
    #[serde(default)]
    pub topology: Option<CpuTopology>,
    #[serde(default)]
    pub kvm_hyperv: bool,
    #[serde(default = "default_cpuconfig_max_phys_bits")]
    pub max_phys_bits: u8,
    #[serde(default)]
    pub affinity: Option<Vec<CpuAffinity>>,
    #[serde(default)]
    pub features: CpuFeatures,
}

pub const DEFAULT_VCPUS: u32 = 1;

impl Default for CpusConfig {
    fn default() -> Self {
        CpusConfig {
            boot_vcpus: DEFAULT_VCPUS,
            max_vcpus: DEFAULT_VCPUS,
            topology: None,
            kvm_hyperv: false,
            max_phys_bits: DEFAULT_MAX_PHYS_BITS,
            affinity: None,
            features: CpuFeatures::default(),
        }
    }
}

pub const DEFAULT_NUM_PCI_SEGMENTS: u16 = 1;
pub fn default_platformconfig_num_pci_segments() -> u16 {
    DEFAULT_NUM_PCI_SEGMENTS
}

pub const DEFAULT_IOMMU_ADDRESS_WIDTH_BITS: u8 = 64;
pub fn default_platformconfig_iommu_address_width_bits() -> u8 {
    DEFAULT_IOMMU_ADDRESS_WIDTH_BITS
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct PlatformConfig {
    #[serde(default = "default_platformconfig_num_pci_segments")]
    pub num_pci_segments: u16,
    #[serde(default)]
    pub iommu_segments: Option<Vec<u16>>,
    #[serde(default = "default_platformconfig_iommu_address_width_bits")]
    pub iommu_address_width_bits: u8,
    #[serde(default)]
    pub serial_number: Option<String>,
    #[serde(default)]
    pub uuid: Option<String>,
    #[serde(default)]
    pub oem_strings: Option<Vec<String>>,
    #[cfg(feature = "tdx")]
    #[serde(default)]
    pub tdx: bool,
    #[cfg(feature = "sev_snp")]
    #[serde(default)]
    pub sev_snp: bool,
}

pub const DEFAULT_PCI_SEGMENT_APERTURE_WEIGHT: u32 = 1;

fn default_pci_segment_aperture_weight() -> u32 {
    DEFAULT_PCI_SEGMENT_APERTURE_WEIGHT
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct PciSegmentConfig {
    #[serde(default)]
    pub pci_segment: u16,
    #[serde(default = "default_pci_segment_aperture_weight")]
    pub mmio32_aperture_weight: u32,
    #[serde(default = "default_pci_segment_aperture_weight")]
    pub mmio64_aperture_weight: u32,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct MemoryZoneConfig {
    pub id: String,
    pub size: u64,
    #[serde(default)]
    pub file: Option<PathBuf>,
    #[serde(default)]
    pub shared: bool,
    #[serde(default)]
    pub hugepages: bool,
    #[serde(default)]
    pub hugepage_size: Option<u64>,
    #[serde(default)]
    pub host_numa_node: Option<u32>,
    #[serde(default)]
    pub hotplug_size: Option<u64>,
    #[serde(default)]
    pub hotplugged_size: Option<u64>,
    #[serde(default)]
    pub prefault: bool,
}

impl ApplyLandlock for MemoryZoneConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        if let Some(file) = &self.file {
            landlock.add_rule_with_access(file, "rw")?;
        }
        Ok(())
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, Deserialize, Serialize, Default)]
pub enum HotplugMethod {
    #[default]
    Acpi,
    VirtioMem,
}

fn default_memoryconfig_thp() -> bool {
    true
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct MemoryConfig {
    pub size: u64,
    #[serde(default)]
    pub mergeable: bool,
    #[serde(default)]
    pub hotplug_method: HotplugMethod,
    #[serde(default)]
    pub hotplug_size: Option<u64>,
    #[serde(default)]
    pub hotplugged_size: Option<u64>,
    #[serde(default)]
    pub shared: bool,
    #[serde(default)]
    pub hugepages: bool,
    #[serde(default)]
    pub hugepage_size: Option<u64>,
    #[serde(default)]
    pub prefault: bool,
    #[serde(default)]
    pub zones: Option<Vec<MemoryZoneConfig>>,
    #[serde(default = "default_memoryconfig_thp")]
    pub thp: bool,
}

pub const DEFAULT_MEMORY_MB: u64 = 512;

impl Default for MemoryConfig {
    fn default() -> Self {
        MemoryConfig {
            size: DEFAULT_MEMORY_MB << 20,
            mergeable: false,
            hotplug_method: HotplugMethod::Acpi,
            hotplug_size: None,
            hotplugged_size: None,
            shared: false,
            hugepages: false,
            hugepage_size: None,
            prefault: false,
            zones: None,
            thp: true,
        }
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize, Default)]
pub enum VhostMode {
    #[default]
    Client,
    Server,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct RateLimiterGroupConfig {
    #[serde(default)]
    pub id: String,
    #[serde(default)]
    pub rate_limiter_config: RateLimiterConfig,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct VirtQueueAffinity {
    pub queue_index: u16,
    pub host_cpus: Vec<usize>,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct DiskConfig {
    pub path: Option<PathBuf>,
    #[serde(default)]
    pub readonly: bool,
    #[serde(default)]
    pub direct: bool,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default = "default_diskconfig_num_queues")]
    pub num_queues: usize,
    #[serde(default = "default_diskconfig_queue_size")]
    pub queue_size: u16,
    #[serde(default)]
    pub vhost_user: bool,
    pub vhost_socket: Option<String>,
    #[serde(default)]
    pub rate_limit_group: Option<String>,
    #[serde(default)]
    pub rate_limiter_config: Option<RateLimiterConfig>,
    #[serde(default)]
    pub id: Option<String>,
    // For testing use only. Not exposed in API.
    #[serde(default)]
    pub disable_io_uring: bool,
    // For testing use only. Not exposed in API.
    #[serde(default)]
    pub disable_aio: bool,
    #[serde(default)]
    pub pci_segment: u16,
    #[serde(default)]
    pub serial: Option<String>,
    #[serde(default)]
    pub queue_affinity: Option<Vec<VirtQueueAffinity>>,
}

impl ApplyLandlock for DiskConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        if let Some(path) = &self.path {
            landlock.add_rule_with_access(path, "rw")?;
        }
        Ok(())
    }
}

pub const DEFAULT_DISK_NUM_QUEUES: usize = 1;

pub fn default_diskconfig_num_queues() -> usize {
    DEFAULT_DISK_NUM_QUEUES
}

pub const DEFAULT_DISK_QUEUE_SIZE: u16 = 128;

pub fn default_diskconfig_queue_size() -> u16 {
    DEFAULT_DISK_QUEUE_SIZE
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct NetConfig {
    #[serde(default = "default_netconfig_tap")]
    pub tap: Option<String>,
    pub ip: Option<IpAddr>,
    pub mask: Option<IpAddr>,
    #[serde(default = "default_netconfig_mac")]
    pub mac: MacAddr,
    #[serde(default)]
    pub host_mac: Option<MacAddr>,
    #[serde(default)]
    pub mtu: Option<u16>,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default = "default_netconfig_num_queues")]
    pub num_queues: usize,
    #[serde(default = "default_netconfig_queue_size")]
    pub queue_size: u16,
    #[serde(default)]
    pub vhost_user: bool,
    pub vhost_socket: Option<String>,
    #[serde(default)]
    pub vhost_mode: VhostMode,
    #[serde(default)]
    pub id: Option<String>,
    // Special (de)serialize handling:
    // Therefore, we don't serialize FDs, and whatever value is here after
    // deserialization is invalid.
    //
    // Valid FDs are transmitted via a different channel (SCM_RIGHTS message)
    // and will be populated into this struct on the destination VMM eventually.
    #[serde(
        default,
        serialize_with = "serialize_netconfig_fds",
        deserialize_with = "deserialize_netconfig_fds"
    )]
    pub fds: Option<Vec<i32>>,
    #[serde(default)]
    pub rate_limiter_config: Option<RateLimiterConfig>,
    #[serde(default)]
    pub pci_segment: u16,
    #[serde(default = "default_netconfig_true")]
    pub offload_tso: bool,
    #[serde(default = "default_netconfig_true")]
    pub offload_ufo: bool,
    #[serde(default = "default_netconfig_true")]
    pub offload_csum: bool,
}

pub fn default_netconfig_true() -> bool {
    true
}

pub fn default_netconfig_tap() -> Option<String> {
    None
}

pub fn default_netconfig_mac() -> MacAddr {
    MacAddr::local_random()
}

pub const DEFAULT_NET_NUM_QUEUES: usize = 2;

pub fn default_netconfig_num_queues() -> usize {
    DEFAULT_NET_NUM_QUEUES
}

pub const DEFAULT_NET_QUEUE_SIZE: u16 = 256;

pub fn default_netconfig_queue_size() -> u16 {
    DEFAULT_NET_QUEUE_SIZE
}

fn serialize_netconfig_fds<S>(x: &Option<Vec<i32>>, s: S) -> Result<S::Ok, S::Error>
where
    S: serde::Serializer,
{
    if let Some(x) = x {
        debug!("FDs in 'NetConfig' won't be serialized as they are most likely invalid after deserialization; using -1.");
        let invalid_fds = vec![-1; x.len()];
        s.serialize_some(&invalid_fds)
    } else {
        s.serialize_none()
    }
}

fn deserialize_netconfig_fds<'de, D>(d: D) -> Result<Option<Vec<i32>>, D::Error>
where
    D: serde::Deserializer<'de>,
{
    let invalid_fds: Option<Vec<i32>> = Option::deserialize(d)?;
    if let Some(invalid_fds) = invalid_fds {
        debug!(
            "FDs in 'NetConfig' won't be deserialized as they are most likely invalid now. Deserializing them as -1."
        );
        Ok(Some(vec![-1; invalid_fds.len()]))
    } else {
        Ok(None)
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct RngConfig {
    pub src: PathBuf,
    #[serde(default)]
    pub iommu: bool,
}

pub const DEFAULT_RNG_SOURCE: &str = "/dev/urandom";

impl Default for RngConfig {
    fn default() -> Self {
        RngConfig {
            src: PathBuf::from(DEFAULT_RNG_SOURCE),
            iommu: false,
        }
    }
}

impl ApplyLandlock for RngConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        // Rng Path only need read access
        landlock.add_rule_with_access(&self.src, "r")?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct BalloonConfig {
    pub size: u64,
    /// Option to deflate the balloon in case the guest is out of memory.
    #[serde(default)]
    pub deflate_on_oom: bool,
    /// Option to enable free page reporting from the guest.
    #[serde(default)]
    pub free_page_reporting: bool,
}

#[cfg(feature = "pvmemcontrol")]
#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize, Default)]
pub struct PvmemcontrolConfig {}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct FsConfig {
    pub tag: String,
    pub socket: PathBuf,
    #[serde(default = "default_fsconfig_num_queues")]
    pub num_queues: usize,
    #[serde(default = "default_fsconfig_queue_size")]
    pub queue_size: u16,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
}

pub fn default_fsconfig_num_queues() -> usize {
    1
}

pub fn default_fsconfig_queue_size() -> u16 {
    1024
}

impl ApplyLandlock for FsConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        landlock.add_rule_with_access(&self.socket, "rw")?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct PmemConfig {
    pub file: PathBuf,
    #[serde(default)]
    pub size: Option<u64>,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default)]
    pub discard_writes: bool,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
}

impl ApplyLandlock for PmemConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        let access = if self.discard_writes { "r" } else { "rw" };
        landlock.add_rule_with_access(&self.file, access)?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub enum ConsoleOutputMode {
    Off,
    Pty,
    Tty,
    File,
    Socket,
    Null,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct ConsoleConfig {
    #[serde(default = "default_consoleconfig_file")]
    pub file: Option<PathBuf>,
    pub mode: ConsoleOutputMode,
    #[serde(default)]
    pub iommu: bool,
    pub socket: Option<PathBuf>,
}

pub fn default_consoleconfig_file() -> Option<PathBuf> {
    None
}

impl ApplyLandlock for ConsoleConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        if let Some(file) = &self.file {
            landlock.add_rule_with_access(file, "rw")?;
        }
        if let Some(socket) = &self.socket {
            landlock.add_rule_with_access(socket, "rw")?;
        }
        Ok(())
    }
}

#[cfg(target_arch = "x86_64")]
#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct DebugConsoleConfig {
    #[serde(default)]
    pub file: Option<PathBuf>,
    pub mode: ConsoleOutputMode,
    /// Optionally dedicated I/O-port, if the default port should not be used.
    pub iobase: Option<u16>,
}

#[cfg(target_arch = "x86_64")]
impl Default for DebugConsoleConfig {
    fn default() -> Self {
        Self {
            file: None,
            mode: ConsoleOutputMode::Off,
            iobase: Some(devices::debug_console::DEFAULT_PORT as u16),
        }
    }
}
#[cfg(target_arch = "x86_64")]
impl ApplyLandlock for DebugConsoleConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        if let Some(file) = &self.file {
            landlock.add_rule_with_access(file, "rw")?;
        }
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct DeviceConfig {
    pub path: PathBuf,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
    #[serde(default)]
    pub x_nv_gpudirect_clique: Option<u8>,
}

impl ApplyLandlock for DeviceConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        let device_path = fs::read_link(self.path.as_path()).map_err(LandlockError::OpenPath)?;
        let iommu_group = device_path.file_name();
        let iommu_group_str = iommu_group
            .ok_or(LandlockError::InvalidPath)?
            .to_str()
            .ok_or(LandlockError::InvalidPath)?;

        let mut vfio_group_path = PathBuf::from("/dev/vfio");
        vfio_group_path.push(iommu_group_str);
        landlock.add_rule_with_access(&vfio_group_path, "rw")?;

        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct UserDeviceConfig {
    pub socket: PathBuf,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
}

impl ApplyLandlock for UserDeviceConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        landlock.add_rule_with_access(&self.socket, "rw")?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct VdpaConfig {
    pub path: PathBuf,
    #[serde(default = "default_vdpaconfig_num_queues")]
    pub num_queues: usize,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
}

pub fn default_vdpaconfig_num_queues() -> usize {
    1
}

impl ApplyLandlock for VdpaConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        landlock.add_rule_with_access(&self.path, "rw")?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct VsockConfig {
    pub cid: u32,
    pub socket: PathBuf,
    #[serde(default)]
    pub iommu: bool,
    #[serde(default)]
    pub id: Option<String>,
    #[serde(default)]
    pub pci_segment: u16,
}

impl ApplyLandlock for VsockConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        if let Some(parent) = self.socket.parent() {
            landlock.add_rule_with_access(parent, "w")?;
        }

        landlock.add_rule_with_access(&self.socket, "rw")?;

        Ok(())
    }
}

#[cfg(feature = "ivshmem")]
pub const DEFAULT_IVSHMEM_SIZE: usize = 128;

#[cfg(feature = "ivshmem")]
#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct IvshmemConfig {
    pub path: PathBuf,
    pub size: usize,
}

#[cfg(feature = "ivshmem")]
impl Default for IvshmemConfig {
    fn default() -> Self {
        Self {
            path: PathBuf::new(),
            size: DEFAULT_IVSHMEM_SIZE << 20,
        }
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct NumaDistance {
    #[serde(default)]
    pub destination: u32,
    #[serde(default)]
    pub distance: u8,
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct NumaConfig {
    #[serde(default)]
    pub guest_numa_id: u32,
    #[serde(default)]
    pub cpus: Option<Vec<u32>>,
    #[serde(default)]
    pub distances: Option<Vec<NumaDistance>>,
    #[serde(default)]
    pub memory_zones: Option<Vec<String>>,
    #[serde(default)]
    pub pci_segments: Option<Vec<u16>>,
}

/// Errors describing a misconfigured payload, i.e., a configuration that
/// can't be booted by Cloud Hypervisor.
///
/// This typically is the case for invalid combinations of cmdline, kernel,
/// firmware, and initrd.
#[derive(Debug, Error, PartialEq, Eq)]
pub enum PayloadConfigError {
    /// Specifying a kernel is not supported when a firmware is provided.
    #[error("Specifying a kernel is not supported when a firmware is provided")]
    FirmwarePlusOtherPayloads,
    /// No bootitem provided: neither firmware nor kernel.
    #[error("No bootitem provided: neither firmware nor kernel")]
    MissingBootitem,
}

#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
pub struct PayloadConfig {
    #[serde(default)]
    pub firmware: Option<PathBuf>,
    #[serde(default)]
    pub kernel: Option<PathBuf>,
    #[serde(default)]
    pub cmdline: Option<String>,
    #[serde(default)]
    pub initramfs: Option<PathBuf>,
    #[cfg(feature = "igvm")]
    #[serde(default)]
    pub igvm: Option<PathBuf>,
    #[cfg(feature = "sev_snp")]
    #[serde(default)]
    pub host_data: Option<String>,
    #[cfg(feature = "fw_cfg")]
    pub fw_cfg_config: Option<FwCfgConfig>,
}

#[cfg(feature = "fw_cfg")]
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
pub struct FwCfgConfig {
    pub e820: bool,
    pub kernel: bool,
    pub cmdline: bool,
    pub initramfs: bool,
    pub acpi_tables: bool,
    pub items: Option<FwCfgItemList>,
}

#[cfg(feature = "fw_cfg")]
impl Default for FwCfgConfig {
    fn default() -> Self {
        FwCfgConfig {
            e820: true,
            kernel: true,
            cmdline: true,
            initramfs: true,
            acpi_tables: true,
            items: None,
        }
    }
}

#[cfg(feature = "fw_cfg")]
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
pub struct FwCfgItemList {
    #[serde(default)]
    pub item_list: Vec<FwCfgItem>,
}

#[cfg(feature = "fw_cfg")]
#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
pub struct FwCfgItem {
    #[serde(default)]
    pub name: String,
    #[serde(default)]
    pub file: PathBuf,
}

#[cfg(feature = "fw_cfg")]
pub enum FwCfgItemError {
    InvalidValue(String),
}

#[cfg(feature = "fw_cfg")]
impl FromStr for FwCfgItemList {
    type Err = FwCfgItemError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let body = s
            .trim()
            .strip_prefix('[')
            .and_then(|s| s.strip_suffix(']'))
            .ok_or_else(|| FwCfgItemError::InvalidValue(s.to_string()))?;

        let mut fw_cfg_items: Vec<FwCfgItem> = vec![];
        let items: Vec<&str> = body.split(':').collect();
        for item in items {
            fw_cfg_items.push(
                FwCfgItem::parse(item)
                    .map_err(|_| FwCfgItemError::InvalidValue(item.to_string()))?,
            );
        }
        Ok(FwCfgItemList {
            item_list: fw_cfg_items,
        })
    }
}

impl PayloadConfig {
    /// Validates the payload config.
    ///
    /// Succeeds if Cloud Hypervisor will be able to boot the configuration.
    /// Further, warns for some odd configurations.
    pub fn validate(&mut self) -> Result<(), PayloadConfigError> {
        match (&self.firmware, &self.kernel) {
            (Some(_firmware), Some(_kernel)) => Err(PayloadConfigError::FirmwarePlusOtherPayloads),
            (Some(_firmware), None) => {
                if self.cmdline.is_some() {
                    log::warn!("Ignoring cmdline parameter as firmware is provided as the payload");
                    self.cmdline = None;
                }
                if self.initramfs.is_some() {
                    log::warn!(
                        "Ignoring initramfs parameter as firmware is provided as the payload"
                    );
                    self.initramfs = None;
                }
                Ok(())
            }
            (None, Some(_kernel)) => Ok(()),
            (None, None) => Err(PayloadConfigError::MissingBootitem),
        }?;

        Ok(())
    }
}

impl ApplyLandlock for PayloadConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        // Payload only needs read access
        if let Some(firmware) = &self.firmware {
            landlock.add_rule_with_access(firmware, "r")?;
        }

        if let Some(kernel) = &self.kernel {
            landlock.add_rule_with_access(kernel, "r")?;
        }

        if let Some(initramfs) = &self.initramfs {
            landlock.add_rule_with_access(initramfs, "r")?;
        }

        #[cfg(feature = "igvm")]
        if let Some(igvm) = &self.igvm {
            landlock.add_rule_with_access(igvm, "r")?;
        }

        Ok(())
    }
}

pub fn default_serial() -> ConsoleConfig {
    ConsoleConfig {
        file: None,
        mode: ConsoleOutputMode::Null,
        iommu: false,
        socket: None,
    }
}

pub fn default_console() -> ConsoleConfig {
    ConsoleConfig {
        file: None,
        mode: ConsoleOutputMode::Tty,
        iommu: false,
        socket: None,
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct TpmConfig {
    pub socket: PathBuf,
}

impl ApplyLandlock for TpmConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        landlock.add_rule_with_access(&self.socket, "rw")?;
        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct LandlockConfig {
    pub path: PathBuf,
    pub access: String,
}

impl ApplyLandlock for LandlockConfig {
    fn apply_landlock(&self, landlock: &mut Landlock) -> LandlockResult<()> {
        landlock.add_rule_with_access(&self.path, self.access.clone().as_str())?;
        Ok(())
    }
}

#[derive(Debug, PartialEq, Eq, Deserialize, Serialize)]
pub struct VmConfig {
    #[serde(default)]
    pub cpus: CpusConfig,
    #[serde(default)]
    pub memory: MemoryConfig,
    pub payload: Option<PayloadConfig>,
    pub rate_limit_groups: Option<Vec<RateLimiterGroupConfig>>,
    pub disks: Option<Vec<DiskConfig>>,
    pub net: Option<Vec<NetConfig>>,
    #[serde(default)]
    pub rng: RngConfig,
    pub balloon: Option<BalloonConfig>,
    pub fs: Option<Vec<FsConfig>>,
    pub pmem: Option<Vec<PmemConfig>>,
    #[serde(default = "default_serial")]
    pub serial: ConsoleConfig,
    #[serde(default = "default_console")]
    pub console: ConsoleConfig,
    #[cfg(target_arch = "x86_64")]
    #[serde(default)]
    pub debug_console: DebugConsoleConfig,
    pub devices: Option<Vec<DeviceConfig>>,
    pub user_devices: Option<Vec<UserDeviceConfig>>,
    pub vdpa: Option<Vec<VdpaConfig>>,
    pub vsock: Option<VsockConfig>,
    #[cfg(feature = "pvmemcontrol")]
    #[serde(default)]
    pub pvmemcontrol: Option<PvmemcontrolConfig>,
    #[serde(default)]
    pub pvpanic: bool,
    #[serde(default)]
    pub iommu: bool,
    pub numa: Option<Vec<NumaConfig>>,
    #[serde(default)]
    pub watchdog: bool,
    #[cfg(feature = "guest_debug")]
    #[serde(default)]
    pub gdb: bool,
    pub pci_segments: Option<Vec<PciSegmentConfig>>,
    pub platform: Option<PlatformConfig>,
    pub tpm: Option<TpmConfig>,
    // Preserved FDs are the ones that share the same life-time as its holding
    // VmConfig instance, such as FDs for creating TAP devices.
    // Preserved FDs will stay open as long as the holding VmConfig instance is
    // valid, and will be closed when the holding VmConfig instance is destroyed.
    #[serde(skip)]
    pub preserved_fds: Option<Vec<i32>>,
    #[serde(default)]
    pub landlock_enable: bool,
    pub landlock_rules: Option<Vec<LandlockConfig>>,
    #[cfg(feature = "ivshmem")]
    pub ivshmem: Option<IvshmemConfig>,
}

impl VmConfig {
    pub(crate) fn apply_landlock(&self) -> LandlockResult<()> {
        let mut landlock = Landlock::new()?;

        #[cfg(target_arch = "aarch64")]
        {
            landlock.add_rule_with_access(Path::new("/sys/devices/system/cpu/cpu0/cache"), "r")?;
        }

        if let Some(mem_zones) = &self.memory.zones {
            for zone in mem_zones.iter() {
                zone.apply_landlock(&mut landlock)?;
            }
        }

        let disks = &self.disks;
        if let Some(disks) = disks {
            for disk in disks.iter() {
                disk.apply_landlock(&mut landlock)?;
            }
        }

        self.rng.apply_landlock(&mut landlock)?;

        if let Some(fs_configs) = &self.fs {
            for fs_config in fs_configs.iter() {
                fs_config.apply_landlock(&mut landlock)?;
            }
        }

        if let Some(pmem_configs) = &self.pmem {
            for pmem_config in pmem_configs.iter() {
                pmem_config.apply_landlock(&mut landlock)?;
            }
        }

        self.console.apply_landlock(&mut landlock)?;
        self.serial.apply_landlock(&mut landlock)?;

        #[cfg(target_arch = "x86_64")]
        {
            self.debug_console.apply_landlock(&mut landlock)?;
        }

        if let Some(devices) = &self.devices {
            landlock.add_rule_with_access(Path::new("/dev/vfio/vfio"), "rw")?;

            for device in devices.iter() {
                device.apply_landlock(&mut landlock)?;
            }
        }

        if let Some(user_devices) = &self.user_devices {
            for user_devices in user_devices.iter() {
                user_devices.apply_landlock(&mut landlock)?;
            }
        }

        if let Some(vdpa_configs) = &self.vdpa {
            for vdpa_config in vdpa_configs.iter() {
                vdpa_config.apply_landlock(&mut landlock)?;
            }
        }

        if let Some(vsock_config) = &self.vsock {
            vsock_config.apply_landlock(&mut landlock)?;
        }

        if let Some(payload) = &self.payload {
            payload.apply_landlock(&mut landlock)?;
        }

        if let Some(tpm_config) = &self.tpm {
            tpm_config.apply_landlock(&mut landlock)?;
        }

        if self.net.is_some() {
            landlock.add_rule_with_access(Path::new("/dev/net/tun"), "rw")?;
        }

        if let Some(landlock_rules) = &self.landlock_rules {
            for landlock_rule in landlock_rules.iter() {
                landlock_rule.apply_landlock(&mut landlock)?;
            }
        }

        landlock.restrict_self()?;

        Ok(())
    }

    #[cfg(all(feature = "kvm", target_arch = "x86_64"))]
    pub(crate) fn max_apic_id(&self) -> u32 {
        if let Some(topology) = &self.cpus.topology {
            arch::x86_64::get_max_x2apic_id((
                topology.threads_per_core,
                topology.cores_per_die,
                topology.dies_per_package,
                topology.packages,
            ))
        } else {
            self.cpus.max_vcpus
        }
    }
}