alioth 0.12.0

// Copyright 2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#[path = "dev/dev.rs"]
pub mod dev;
pub mod pci;
#[path = "queue/queue.rs"]
pub mod queue;
#[cfg(target_os = "linux")]
pub mod vhost;
#[cfg(target_os = "linux")]
#[path = "vu/vu.rs"]
pub mod vu;
#[path = "worker/worker.rs"]
pub mod worker;

use std::fmt::Debug;
use std::os::fd::BorrowedFd;
use std::path::Path;

use snafu::Snafu;

use crate::errors::{DebugTrace, trace_error};
use crate::{bitflags, consts};

#[trace_error]
#[derive(Snafu, DebugTrace)]
#[snafu(module, context(suffix(false)))]
pub enum Error {
    #[snafu(display("Hypervisor internal error"), context(false))]
    HvError { source: Box<crate::hv::Error> },
    #[snafu(display("Failed to access guest memory"), context(false))]
    Memory { source: Box<crate::mem::Error> },
    #[snafu(display("PCI bus error"), context(false))]
    PciBus { source: crate::pci::Error },
    #[snafu(display("Cannot access file {path:?}"))]
    AccessFile {
        path: Box<Path>,
        error: std::io::Error,
    },
    #[snafu(display("Failed to lock file {path:?}"))]
    LockFile {
        path: Box<Path>,
        error: std::fs::TryLockError,
    },
    #[snafu(display("Error from OS"), context(false))]
    System { error: std::io::Error },
    #[snafu(display("Failed to create a poll"))]
    CreatePoll { error: std::io::Error },
    #[snafu(display("Failed to register/deregister an event source"))]
    EventSource { error: std::io::Error },
    #[snafu(display("Failed to poll events"))]
    PollEvents { error: std::io::Error },
    #[snafu(display("Failed to create a worker thread"))]
    WorkerThread { error: std::io::Error },
    #[snafu(display("Invalid descriptor id {id}"))]
    InvalidDescriptor { id: u16 },
    #[snafu(display("Invalid queue index {index}"))]
    InvalidQueueIndex { index: u16 },
    #[snafu(display("Invalid msix vector {vector}"))]
    InvalidMsixVector { vector: u16 },
    #[snafu(display("Invalid virtq buffer"))]
    InvalidBuffer,
    #[cfg(target_os = "linux")]
    #[snafu(display("vhost-user error"), context(false))]
    Vu { source: Box<vu::Error> },
    #[cfg(target_os = "linux")]
    #[snafu(display("vhost error"), context(false))]
    Vhost { source: Box<vhost::Error> },
    #[snafu(display("fuse error"), context(false))]
    Fuse { source: Box<crate::fuse::Error> },
}

type Result<T, E = Error> = std::result::Result<T, E>;

bitflags! {
    pub struct VirtioFeature(u128) {
        INDIRECT_DESC = 1 << 28;
        EVENT_IDX = 1 << 29;
        VHOST_PROTOCOL = 1 << 30;
        VERSION_1 = 1 << 32;
        ACCESS_PLATFORM = 1 << 33;
        RING_PACKED = 1 << 34;
    }
}

const FEATURE_BUILT_IN: u128 = VirtioFeature::EVENT_IDX.bits()
    | VirtioFeature::RING_PACKED.bits()
    | VirtioFeature::VERSION_1.bits();

consts! {
    pub struct DeviceId(u16) {
        NET = 1;
        BLOCK = 2;
        ENTROPY = 4;
        BALLOON = 5;
        SOCKET = 19;
        IOMMU = 23;
        MEM = 24;
        FILE_SYSTEM = 26;
        PMEM = 27;
    }
}

bitflags! {
    #[derive(Default)]
    pub struct DevStatus(u8) {
        ACK = 1 << 0;
        DRIVER = 1 << 1;
        DRIVER_OK = 1 << 2;
        FEATURES_OK = 1 << 3;
        NEEDS_RESET = 1 << 6;
        FAILED = 1 << 7;
    }
}

pub trait IrqSender: Send + Sync + Debug + 'static {
    fn queue_irq(&self, idx: u16);
    fn config_irq(&self);
    fn queue_irqfd<F, T>(&self, idx: u16, f: F) -> Result<T>
    where
        F: FnOnce(BorrowedFd) -> Result<T>;
    fn config_irqfd<F, T>(&self, f: F) -> Result<T>
    where
        F: FnOnce(BorrowedFd) -> Result<T>;
}

#[cfg(test)]
#[path = "virtio_test.rs"]
mod tests;