Struct disk::composite::CompositeDiskFile

pub struct CompositeDiskFile {
    component_disks: Vec<ComponentDiskPart>,
    _disk_spec_file: File,
}

Represents a composite virtual disk made out of multiple component files. This is described on disk by a protocol buffer file that lists out the component file locations and their offsets and lengths on the virtual disk. The spaces covered by the component disks must be contiguous and not overlapping.

Fields

component_disks: Vec<ComponentDiskPart>

_disk_spec_file: File

Implementations

impl CompositeDiskFile

fn new( disks: Vec<ComponentDiskPart>, disk_spec_file: File ) -> Result<CompositeDiskFile, Error>

pub fn from_file( file: File, params: DiskFileParams ) -> Result<CompositeDiskFile, Error>

Set up a composite disk by reading the specification from a file. The file must consist of the CDISK_MAGIC string followed by one binary instance of the CompositeDisk protocol buffer. Returns an error if it could not read the file or if the specification was invalid.

fn length(&self) -> u64

fn disk_at_offset(&self, offset: u64) -> Result<&ComponentDiskPart>

Trait Implementations

impl AsRawDescriptors for CompositeDiskFile

fn as_raw_descriptors(&self) -> Vec<RawDescriptor>

Returns the underlying raw descriptors.

impl Debug for CompositeDiskFile

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl DiskFile for CompositeDiskFile

fn try_clone(&self) -> Result<Box<dyn DiskFile>>

Creates a new DiskFile instance that shares the same underlying disk file image. IO operations to a DiskFile should affect all DiskFile instances with the same underlying disk file image.

impl DiskGetLen for CompositeDiskFile

fn get_len(&self) -> Result<u64>

Get the current length of the disk in bytes.

impl FileReadWriteAtVolatile for CompositeDiskFile

fn read_at_volatile( &self, slice: VolatileSlice<'_>, offset: u64 ) -> Result<usize>

Reads bytes from this file at offset into the given slice, returning the number of bytes read on success. On Windows file pointer will update with the read, but on Linux the file pointer will not change.

fn write_at_volatile( &self, slice: VolatileSlice<'_>, offset: u64 ) -> Result<usize>

Writes bytes to this file at offset from the given slice, returning the number of bytes written on success. On Windows file pointer will update with the write, but on Linux the file pointer will not change.

fn read_vectored_at_volatile( &self, bufs: &[VolatileSlice<'_>], offset: u64 ) -> Result<usize, Error>

Like read_at_volatile, except it reads to a slice of buffers. Data is copied to fill each buffer in order, with the final buffer written to possibly being only partially filled. This method must behave as a single call to read_at_volatile with the buffers concatenated would. The default implementation calls read_at_volatile with either the first nonempty buffer provided, or returns Ok(0) if none exists. On Windows file pointer will update with the read, but on Linux the file pointer will not change.

fn read_exact_at_volatile( &self, slice: VolatileSlice<'_>, offset: u64 ) -> Result<(), Error>

Reads bytes from this file at offset into the given slice until all bytes in the slice are read, or an error is returned. On Windows file pointer will update with the read, but on Linux the file pointer will not change.

fn write_vectored_at_volatile( &self, bufs: &[VolatileSlice<'_>], offset: u64 ) -> Result<usize, Error>

Like write_at_volatile, except that it writes from a slice of buffers. Data is copied from each buffer in order, with the final buffer read from possibly being only partially consumed. This method must behave as a call to write_at_volatile with the buffers concatenated would. The default implementation calls write_at_volatile with either the first nonempty buffer provided, or returns Ok(0) if none exists. On Windows file pointer will update with the write, but on Linux the file pointer will not change.

fn write_all_at_volatile( &self, slice: VolatileSlice<'_>, offset: u64 ) -> Result<(), Error>

Writes bytes to this file at offset from the given slice until all bytes in the slice are written, or an error is returned. On Windows file pointer will update with the write, but on Linux the file pointer will not change.

impl FileSetLen for CompositeDiskFile

fn set_len(&self, _len: u64) -> Result<()>

impl ToAsyncDisk for CompositeDiskFile

fn to_async_disk(self: Box<Self>, ex: &Executor) -> Result<Box<dyn AsyncDisk>>

Convert a boxed self in to a box-wrapped implementaiton of AsyncDisk. Used to convert a standard disk image to an async disk image. This conversion and the inverse are needed so that the Send DiskImage can be given to the block thread where it is converted to a non-Send AsyncDisk. The AsyncDisk can then be converted back and returned to the main device thread if the block device is destroyed or reset.