mirror of
https://github.com/cloud-hypervisor/cloud-hypervisor.git
synced 2024-08-21 07:21:15 +00:00
Issue from beta verion of clippy: Error: --> vm-virtio/src/queue.rs:700:59 | 700 | if let Some(used_event) = self.get_used_event(&mem) { | ^^^^ help: change this to: `mem` | = note: `-D clippy::needless-borrow` implied by `-D warnings` = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow Signed-off-by: Bo Chen <chen.bo@intel.com>
632 lines
20 KiB
Rust
632 lines
20 KiB
Rust
// Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
|
|
//
|
|
// Portions 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-BSD-3-Clause file.
|
|
//
|
|
// Copyright © 2020 Intel Corporation
|
|
//
|
|
// SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
|
|
|
|
#[macro_use]
|
|
extern crate log;
|
|
|
|
pub mod async_io;
|
|
pub mod fixed_vhd_async;
|
|
pub mod fixed_vhd_sync;
|
|
pub mod qcow_sync;
|
|
pub mod raw_async;
|
|
pub mod raw_sync;
|
|
pub mod vhd;
|
|
|
|
use crate::async_io::{AsyncIo, AsyncIoError, AsyncIoResult, DiskFileError, DiskFileResult};
|
|
#[cfg(feature = "io_uring")]
|
|
use io_uring::{opcode, IoUring, Probe};
|
|
use std::cmp;
|
|
use std::convert::TryInto;
|
|
use std::fs::File;
|
|
use std::io::{self, IoSlice, IoSliceMut, Read, Seek, SeekFrom, Write};
|
|
use std::os::linux::fs::MetadataExt;
|
|
#[cfg(feature = "io_uring")]
|
|
use std::os::unix::io::AsRawFd;
|
|
use std::path::Path;
|
|
use std::result;
|
|
use std::sync::{Arc, Mutex};
|
|
use versionize::{VersionMap, Versionize, VersionizeResult};
|
|
use versionize_derive::Versionize;
|
|
use virtio_bindings::bindings::virtio_blk::*;
|
|
use vm_memory::{
|
|
bitmap::AtomicBitmap, bitmap::Bitmap, ByteValued, Bytes, GuestAddress, GuestMemory,
|
|
GuestMemoryError,
|
|
};
|
|
use vm_virtio::DescriptorChain;
|
|
use vmm_sys_util::eventfd::EventFd;
|
|
|
|
type GuestMemoryMmap = vm_memory::GuestMemoryMmap<AtomicBitmap>;
|
|
|
|
const SECTOR_SHIFT: u8 = 9;
|
|
pub const SECTOR_SIZE: u64 = 0x01 << SECTOR_SHIFT;
|
|
|
|
#[derive(Debug)]
|
|
pub enum Error {
|
|
/// Guest gave us bad memory addresses.
|
|
GuestMemory(GuestMemoryError),
|
|
/// Guest gave us offsets that would have overflowed a usize.
|
|
CheckedOffset(GuestAddress, usize),
|
|
/// Guest gave us a write only descriptor that protocol says to read from.
|
|
UnexpectedWriteOnlyDescriptor,
|
|
/// Guest gave us a read only descriptor that protocol says to write to.
|
|
UnexpectedReadOnlyDescriptor,
|
|
/// Guest gave us too few descriptors in a descriptor chain.
|
|
DescriptorChainTooShort,
|
|
/// Guest gave us a descriptor that was too short to use.
|
|
DescriptorLengthTooSmall,
|
|
/// Getting a block's metadata fails for any reason.
|
|
GetFileMetadata,
|
|
/// The requested operation would cause a seek beyond disk end.
|
|
InvalidOffset,
|
|
/// The requested operation does not support multiple descriptors.
|
|
TooManyDescriptors,
|
|
}
|
|
|
|
fn build_device_id(disk_path: &Path) -> result::Result<String, Error> {
|
|
let blk_metadata = match disk_path.metadata() {
|
|
Err(_) => return Err(Error::GetFileMetadata),
|
|
Ok(m) => m,
|
|
};
|
|
// This is how kvmtool does it.
|
|
let device_id = format!(
|
|
"{}{}{}",
|
|
blk_metadata.st_dev(),
|
|
blk_metadata.st_rdev(),
|
|
blk_metadata.st_ino()
|
|
);
|
|
Ok(device_id)
|
|
}
|
|
|
|
pub fn build_disk_image_id(disk_path: &Path) -> Vec<u8> {
|
|
let mut default_disk_image_id = vec![0; VIRTIO_BLK_ID_BYTES as usize];
|
|
match build_device_id(disk_path) {
|
|
Err(_) => {
|
|
warn!("Could not generate device id. We'll use a default.");
|
|
}
|
|
Ok(m) => {
|
|
// The kernel only knows to read a maximum of VIRTIO_BLK_ID_BYTES.
|
|
// This will also zero out any leftover bytes.
|
|
let disk_id = m.as_bytes();
|
|
let bytes_to_copy = cmp::min(disk_id.len(), VIRTIO_BLK_ID_BYTES as usize);
|
|
default_disk_image_id[..bytes_to_copy].clone_from_slice(&disk_id[..bytes_to_copy])
|
|
}
|
|
}
|
|
default_disk_image_id
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
pub enum ExecuteError {
|
|
BadRequest(Error),
|
|
Flush(io::Error),
|
|
Read(GuestMemoryError),
|
|
Seek(io::Error),
|
|
Write(GuestMemoryError),
|
|
Unsupported(u32),
|
|
SubmitIoUring(io::Error),
|
|
GetHostAddress(GuestMemoryError),
|
|
AsyncRead(AsyncIoError),
|
|
AsyncWrite(AsyncIoError),
|
|
AsyncFlush(AsyncIoError),
|
|
}
|
|
|
|
impl ExecuteError {
|
|
pub fn status(&self) -> u32 {
|
|
match *self {
|
|
ExecuteError::BadRequest(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::Flush(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::Read(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::Seek(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::Write(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::Unsupported(_) => VIRTIO_BLK_S_UNSUPP,
|
|
ExecuteError::SubmitIoUring(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::GetHostAddress(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::AsyncRead(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::AsyncWrite(_) => VIRTIO_BLK_S_IOERR,
|
|
ExecuteError::AsyncFlush(_) => VIRTIO_BLK_S_IOERR,
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Copy, Debug, PartialEq)]
|
|
pub enum RequestType {
|
|
In,
|
|
Out,
|
|
Flush,
|
|
GetDeviceId,
|
|
Unsupported(u32),
|
|
}
|
|
|
|
pub fn request_type(
|
|
mem: &GuestMemoryMmap,
|
|
desc_addr: GuestAddress,
|
|
) -> result::Result<RequestType, Error> {
|
|
let type_ = mem.read_obj(desc_addr).map_err(Error::GuestMemory)?;
|
|
match type_ {
|
|
VIRTIO_BLK_T_IN => Ok(RequestType::In),
|
|
VIRTIO_BLK_T_OUT => Ok(RequestType::Out),
|
|
VIRTIO_BLK_T_FLUSH => Ok(RequestType::Flush),
|
|
VIRTIO_BLK_T_GET_ID => Ok(RequestType::GetDeviceId),
|
|
t => Ok(RequestType::Unsupported(t)),
|
|
}
|
|
}
|
|
|
|
fn sector(mem: &GuestMemoryMmap, desc_addr: GuestAddress) -> result::Result<u64, Error> {
|
|
const SECTOR_OFFSET: usize = 8;
|
|
let addr = match mem.checked_offset(desc_addr, SECTOR_OFFSET) {
|
|
Some(v) => v,
|
|
None => return Err(Error::CheckedOffset(desc_addr, SECTOR_OFFSET)),
|
|
};
|
|
|
|
mem.read_obj(addr).map_err(Error::GuestMemory)
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
pub struct Request {
|
|
pub request_type: RequestType,
|
|
pub sector: u64,
|
|
pub data_descriptors: Vec<(GuestAddress, u32)>,
|
|
pub status_addr: GuestAddress,
|
|
pub writeback: bool,
|
|
}
|
|
|
|
impl Request {
|
|
pub fn parse(
|
|
avail_desc: &DescriptorChain,
|
|
mem: &GuestMemoryMmap,
|
|
) -> result::Result<Request, Error> {
|
|
// The head contains the request type which MUST be readable.
|
|
if avail_desc.is_write_only() {
|
|
return Err(Error::UnexpectedWriteOnlyDescriptor);
|
|
}
|
|
|
|
let mut req = Request {
|
|
request_type: request_type(mem, avail_desc.addr)?,
|
|
sector: sector(mem, avail_desc.addr)?,
|
|
data_descriptors: Vec::new(),
|
|
status_addr: GuestAddress(0),
|
|
writeback: true,
|
|
};
|
|
|
|
let status_desc;
|
|
let mut desc = avail_desc
|
|
.next_descriptor()
|
|
.ok_or(Error::DescriptorChainTooShort)
|
|
.map_err(|e| {
|
|
error!("Only head descriptor present: request = {:?}", req);
|
|
e
|
|
})?;
|
|
|
|
if !desc.has_next() {
|
|
status_desc = desc;
|
|
// Only flush requests are allowed to skip the data descriptor.
|
|
if req.request_type != RequestType::Flush {
|
|
error!("Need a data descriptor: request = {:?}", req);
|
|
return Err(Error::DescriptorChainTooShort);
|
|
}
|
|
} else {
|
|
while desc.has_next() {
|
|
if desc.is_write_only() && req.request_type == RequestType::Out {
|
|
return Err(Error::UnexpectedWriteOnlyDescriptor);
|
|
}
|
|
if !desc.is_write_only() && req.request_type == RequestType::In {
|
|
return Err(Error::UnexpectedReadOnlyDescriptor);
|
|
}
|
|
if !desc.is_write_only() && req.request_type == RequestType::GetDeviceId {
|
|
return Err(Error::UnexpectedReadOnlyDescriptor);
|
|
}
|
|
req.data_descriptors.push((desc.addr, desc.len));
|
|
desc = desc
|
|
.next_descriptor()
|
|
.ok_or(Error::DescriptorChainTooShort)
|
|
.map_err(|e| {
|
|
error!("DescriptorChain corrupted: request = {:?}", req);
|
|
e
|
|
})?;
|
|
}
|
|
status_desc = desc;
|
|
}
|
|
|
|
// The status MUST always be writable.
|
|
if !status_desc.is_write_only() {
|
|
return Err(Error::UnexpectedReadOnlyDescriptor);
|
|
}
|
|
|
|
if status_desc.len < 1 {
|
|
return Err(Error::DescriptorLengthTooSmall);
|
|
}
|
|
|
|
req.status_addr = status_desc.addr;
|
|
|
|
Ok(req)
|
|
}
|
|
|
|
#[allow(clippy::ptr_arg)]
|
|
pub fn execute<T: Seek + Read + Write>(
|
|
&self,
|
|
disk: &mut T,
|
|
disk_nsectors: u64,
|
|
mem: &GuestMemoryMmap,
|
|
disk_id: &Vec<u8>,
|
|
) -> result::Result<u32, ExecuteError> {
|
|
disk.seek(SeekFrom::Start(self.sector << SECTOR_SHIFT))
|
|
.map_err(ExecuteError::Seek)?;
|
|
let mut len = 0;
|
|
for (data_addr, data_len) in &self.data_descriptors {
|
|
let mut top: u64 = u64::from(*data_len) / SECTOR_SIZE;
|
|
if u64::from(*data_len) % SECTOR_SIZE != 0 {
|
|
top += 1;
|
|
}
|
|
top = top
|
|
.checked_add(self.sector)
|
|
.ok_or(ExecuteError::BadRequest(Error::InvalidOffset))?;
|
|
if top > disk_nsectors {
|
|
return Err(ExecuteError::BadRequest(Error::InvalidOffset));
|
|
}
|
|
|
|
match self.request_type {
|
|
RequestType::In => {
|
|
mem.read_exact_from(*data_addr, disk, *data_len as usize)
|
|
.map_err(ExecuteError::Read)?;
|
|
len += data_len;
|
|
}
|
|
RequestType::Out => {
|
|
mem.write_all_to(*data_addr, disk, *data_len as usize)
|
|
.map_err(ExecuteError::Write)?;
|
|
if !self.writeback {
|
|
disk.flush().map_err(ExecuteError::Flush)?;
|
|
}
|
|
}
|
|
RequestType::Flush => disk.flush().map_err(ExecuteError::Flush)?,
|
|
RequestType::GetDeviceId => {
|
|
if (*data_len as usize) < disk_id.len() {
|
|
return Err(ExecuteError::BadRequest(Error::InvalidOffset));
|
|
}
|
|
mem.write_slice(disk_id.as_slice(), *data_addr)
|
|
.map_err(ExecuteError::Write)?;
|
|
}
|
|
RequestType::Unsupported(t) => return Err(ExecuteError::Unsupported(t)),
|
|
};
|
|
}
|
|
Ok(len)
|
|
}
|
|
|
|
pub fn execute_async(
|
|
&self,
|
|
mem: &GuestMemoryMmap,
|
|
disk_nsectors: u64,
|
|
disk_image: &mut dyn AsyncIo,
|
|
disk_id: &[u8],
|
|
user_data: u64,
|
|
) -> result::Result<bool, ExecuteError> {
|
|
let sector = self.sector;
|
|
let request_type = self.request_type;
|
|
let offset = (sector << SECTOR_SHIFT) as libc::off_t;
|
|
|
|
let mut iovecs = Vec::new();
|
|
for (data_addr, data_len) in &self.data_descriptors {
|
|
let mut top: u64 = u64::from(*data_len) / SECTOR_SIZE;
|
|
if u64::from(*data_len) % SECTOR_SIZE != 0 {
|
|
top += 1;
|
|
}
|
|
top = top
|
|
.checked_add(sector)
|
|
.ok_or(ExecuteError::BadRequest(Error::InvalidOffset))?;
|
|
if top > disk_nsectors {
|
|
return Err(ExecuteError::BadRequest(Error::InvalidOffset));
|
|
}
|
|
|
|
let buf = mem
|
|
.get_slice(*data_addr, *data_len as usize)
|
|
.map_err(ExecuteError::GetHostAddress)?
|
|
.as_ptr();
|
|
let iovec = libc::iovec {
|
|
iov_base: buf as *mut libc::c_void,
|
|
iov_len: *data_len as libc::size_t,
|
|
};
|
|
iovecs.push(iovec);
|
|
}
|
|
|
|
// Queue operations expected to be submitted.
|
|
match request_type {
|
|
RequestType::In => {
|
|
for (data_addr, data_len) in &self.data_descriptors {
|
|
mem.get_slice(*data_addr, *data_len as usize)
|
|
.map_err(ExecuteError::GetHostAddress)?
|
|
.bitmap()
|
|
.mark_dirty(0, *data_len as usize);
|
|
}
|
|
disk_image
|
|
.read_vectored(offset, iovecs, user_data)
|
|
.map_err(ExecuteError::AsyncRead)?;
|
|
}
|
|
RequestType::Out => {
|
|
disk_image
|
|
.write_vectored(offset, iovecs, user_data)
|
|
.map_err(ExecuteError::AsyncWrite)?;
|
|
}
|
|
RequestType::Flush => {
|
|
disk_image
|
|
.fsync(Some(user_data))
|
|
.map_err(ExecuteError::AsyncFlush)?;
|
|
}
|
|
RequestType::GetDeviceId => {
|
|
let (data_addr, data_len) = if self.data_descriptors.len() == 1 {
|
|
(self.data_descriptors[0].0, self.data_descriptors[0].1)
|
|
} else {
|
|
return Err(ExecuteError::BadRequest(Error::TooManyDescriptors));
|
|
};
|
|
if (data_len as usize) < disk_id.len() {
|
|
return Err(ExecuteError::BadRequest(Error::InvalidOffset));
|
|
}
|
|
mem.write_slice(disk_id, data_addr)
|
|
.map_err(ExecuteError::Write)?;
|
|
return Ok(false);
|
|
}
|
|
RequestType::Unsupported(t) => return Err(ExecuteError::Unsupported(t)),
|
|
}
|
|
|
|
Ok(true)
|
|
}
|
|
|
|
pub fn set_writeback(&mut self, writeback: bool) {
|
|
self.writeback = writeback
|
|
}
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug, Default, Versionize)]
|
|
#[repr(C, packed)]
|
|
pub struct VirtioBlockConfig {
|
|
pub capacity: u64,
|
|
pub size_max: u32,
|
|
pub seg_max: u32,
|
|
pub geometry: VirtioBlockGeometry,
|
|
pub blk_size: u32,
|
|
pub physical_block_exp: u8,
|
|
pub alignment_offset: u8,
|
|
pub min_io_size: u16,
|
|
pub opt_io_size: u32,
|
|
pub writeback: u8,
|
|
pub unused: u8,
|
|
pub num_queues: u16,
|
|
pub max_discard_sectors: u32,
|
|
pub max_discard_seg: u32,
|
|
pub discard_sector_alignment: u32,
|
|
pub max_write_zeroes_sectors: u32,
|
|
pub max_write_zeroes_seg: u32,
|
|
pub write_zeroes_may_unmap: u8,
|
|
pub unused1: [u8; 3],
|
|
}
|
|
unsafe impl ByteValued for VirtioBlockConfig {}
|
|
|
|
#[derive(Copy, Clone, Debug, Default, Versionize)]
|
|
#[repr(C, packed)]
|
|
pub struct VirtioBlockGeometry {
|
|
pub cylinders: u16,
|
|
pub heads: u8,
|
|
pub sectors: u8,
|
|
}
|
|
unsafe impl ByteValued for VirtioBlockGeometry {}
|
|
|
|
/// Check if io_uring for block device can be used on the current system, as
|
|
/// it correctly supports the expected io_uring features.
|
|
#[cfg(feature = "io_uring")]
|
|
pub fn block_io_uring_is_supported() -> bool {
|
|
let error_msg = "io_uring not supported:";
|
|
|
|
// Check we can create an io_uring instance, which effectively verifies
|
|
// that io_uring_setup() syscall is supported.
|
|
let io_uring = match IoUring::new(1) {
|
|
Ok(io_uring) => io_uring,
|
|
Err(e) => {
|
|
info!("{} failed to create io_uring instance: {}", error_msg, e);
|
|
return false;
|
|
}
|
|
};
|
|
|
|
let submitter = io_uring.submitter();
|
|
|
|
let event_fd = match EventFd::new(libc::EFD_NONBLOCK) {
|
|
Ok(fd) => fd,
|
|
Err(e) => {
|
|
info!("{} failed to create eventfd: {}", error_msg, e);
|
|
return false;
|
|
}
|
|
};
|
|
|
|
// Check we can register an eventfd as this is going to be needed while
|
|
// using io_uring with the virtio block device. This also validates that
|
|
// io_uring_register() syscall is supported.
|
|
match submitter.register_eventfd(event_fd.as_raw_fd()) {
|
|
Ok(_) => {}
|
|
Err(e) => {
|
|
info!("{} failed to register eventfd: {}", error_msg, e);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
let mut probe = Probe::new();
|
|
|
|
// Check we can register a probe to validate supported operations.
|
|
match submitter.register_probe(&mut probe) {
|
|
Ok(_) => {}
|
|
Err(e) => {
|
|
info!("{} failed to register a probe: {}", error_msg, e);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Check IORING_OP_FSYNC is supported
|
|
if !probe.is_supported(opcode::Fsync::CODE) {
|
|
info!("{} IORING_OP_FSYNC operation not supported", error_msg);
|
|
return false;
|
|
}
|
|
|
|
// Check IORING_OP_READ is supported
|
|
if !probe.is_supported(opcode::Read::CODE) {
|
|
info!("{} IORING_OP_READ operation not supported", error_msg);
|
|
return false;
|
|
}
|
|
|
|
// Check IORING_OP_WRITE is supported
|
|
if !probe.is_supported(opcode::Write::CODE) {
|
|
info!("{} IORING_OP_WRITE operation not supported", error_msg);
|
|
return false;
|
|
}
|
|
|
|
true
|
|
}
|
|
|
|
#[cfg(not(feature = "io_uring"))]
|
|
pub fn block_io_uring_is_supported() -> bool {
|
|
false
|
|
}
|
|
|
|
pub fn disk_size(file: &mut dyn Seek, semaphore: &mut Arc<Mutex<()>>) -> DiskFileResult<u64> {
|
|
// Take the semaphore to ensure other threads are not interacting with
|
|
// the underlying file.
|
|
let _lock = semaphore.lock().unwrap();
|
|
|
|
Ok(file.seek(SeekFrom::End(0)).map_err(DiskFileError::Size)? as u64)
|
|
}
|
|
|
|
pub trait ReadSeekFile: Read + Seek {}
|
|
impl<F: Read + Seek> ReadSeekFile for F {}
|
|
|
|
pub fn read_vectored_sync(
|
|
offset: libc::off_t,
|
|
iovecs: Vec<libc::iovec>,
|
|
user_data: u64,
|
|
file: &mut dyn ReadSeekFile,
|
|
eventfd: &EventFd,
|
|
completion_list: &mut Vec<(u64, i32)>,
|
|
semaphore: &mut Arc<Mutex<()>>,
|
|
) -> AsyncIoResult<()> {
|
|
// Convert libc::iovec into IoSliceMut
|
|
let mut slices = Vec::new();
|
|
for iovec in iovecs.iter() {
|
|
slices.push(IoSliceMut::new(unsafe { std::mem::transmute(*iovec) }));
|
|
}
|
|
|
|
let result = {
|
|
// Take the semaphore to ensure other threads are not interacting
|
|
// with the underlying file.
|
|
let _lock = semaphore.lock().unwrap();
|
|
|
|
// Move the cursor to the right offset
|
|
file.seek(SeekFrom::Start(offset as u64))
|
|
.map_err(AsyncIoError::ReadVectored)?;
|
|
|
|
// Read vectored
|
|
file.read_vectored(slices.as_mut_slice())
|
|
.map_err(AsyncIoError::ReadVectored)?
|
|
};
|
|
|
|
completion_list.push((user_data, result as i32));
|
|
eventfd.write(1).unwrap();
|
|
|
|
Ok(())
|
|
}
|
|
|
|
pub trait WriteSeekFile: Write + Seek {}
|
|
impl<F: Write + Seek> WriteSeekFile for F {}
|
|
|
|
pub fn write_vectored_sync(
|
|
offset: libc::off_t,
|
|
iovecs: Vec<libc::iovec>,
|
|
user_data: u64,
|
|
file: &mut dyn WriteSeekFile,
|
|
eventfd: &EventFd,
|
|
completion_list: &mut Vec<(u64, i32)>,
|
|
semaphore: &mut Arc<Mutex<()>>,
|
|
) -> AsyncIoResult<()> {
|
|
// Convert libc::iovec into IoSlice
|
|
let mut slices = Vec::new();
|
|
for iovec in iovecs.iter() {
|
|
slices.push(IoSlice::new(unsafe { std::mem::transmute(*iovec) }));
|
|
}
|
|
|
|
let result = {
|
|
// Take the semaphore to ensure other threads are not interacting
|
|
// with the underlying file.
|
|
let _lock = semaphore.lock().unwrap();
|
|
|
|
// Move the cursor to the right offset
|
|
file.seek(SeekFrom::Start(offset as u64))
|
|
.map_err(AsyncIoError::WriteVectored)?;
|
|
|
|
// Write vectored
|
|
file.write_vectored(slices.as_slice())
|
|
.map_err(AsyncIoError::WriteVectored)?
|
|
};
|
|
|
|
completion_list.push((user_data, result as i32));
|
|
eventfd.write(1).unwrap();
|
|
|
|
Ok(())
|
|
}
|
|
|
|
pub fn fsync_sync(
|
|
user_data: Option<u64>,
|
|
file: &mut dyn Write,
|
|
eventfd: &EventFd,
|
|
completion_list: &mut Vec<(u64, i32)>,
|
|
semaphore: &mut Arc<Mutex<()>>,
|
|
) -> AsyncIoResult<()> {
|
|
let result: i32 = {
|
|
// Take the semaphore to ensure other threads are not interacting
|
|
// with the underlying file.
|
|
let _lock = semaphore.lock().unwrap();
|
|
|
|
// Flush
|
|
file.flush().map_err(AsyncIoError::Fsync)?;
|
|
|
|
0
|
|
};
|
|
|
|
if let Some(user_data) = user_data {
|
|
completion_list.push((user_data, result));
|
|
eventfd.write(1).unwrap();
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
pub enum ImageType {
|
|
FixedVhd,
|
|
Qcow2,
|
|
Raw,
|
|
}
|
|
|
|
const QCOW_MAGIC: u32 = 0x5146_49fb;
|
|
|
|
/// Determine image type through file parsing.
|
|
pub fn detect_image_type(f: &mut File) -> std::io::Result<ImageType> {
|
|
// We must create a buffer aligned on 512 bytes with a size being a
|
|
// multiple of 512 bytes as the file might be opened with O_DIRECT flag.
|
|
#[repr(align(512))]
|
|
struct Sector {
|
|
data: [u8; 512],
|
|
}
|
|
let mut s = Sector { data: [0; 512] };
|
|
|
|
f.read_exact(&mut s.data)?;
|
|
|
|
// Check 4 first bytes to get the header value and determine the image type
|
|
let image_type = if u32::from_be_bytes(s.data[0..4].try_into().unwrap()) == QCOW_MAGIC {
|
|
ImageType::Qcow2
|
|
} else if vhd::is_fixed_vhd(f)? {
|
|
ImageType::FixedVhd
|
|
} else {
|
|
ImageType::Raw
|
|
};
|
|
|
|
Ok(image_type)
|
|
}
|