Struct L2Table

pub(super) struct L2Table {
    cluster: Option<HostCluster>,
    data: Box<[AtomicL2Entry]>,
    cluster_bits: u32,
    external_data_file: bool,
    modified: AtomicBool,
    writer_lock: Mutex<()>,
}

L2 table.

Fields

cluster: Option<HostCluster>

Cluster of the L2 table.

data: Box<[AtomicL2Entry]>

Table data.

cluster_bits: u32

log2 of the cluster size.

external_data_file: bool

Whether this image uses an external data file.

modified: AtomicBool

Whether this table has been modified since it was last written.

writer_lock: Mutex<()>

Lock for creating L2TableWriteGuard.

Implementations

impl L2Table

pub fn new_cleared(header: &Header) -> Self

Create a new zeroed L2 table.

pub fn get_mapping(&self, lookup_cluster: GuestCluster) -> Result<L2Mapping>

Look up a cluster mapping.

pub async fn lock_write(&self) -> L2TableWriteGuard<'_>

Allow modifying this L2 table.

Note that readers are allowed to exist while modifications are happening.

Trait Implementations

impl Clone for L2Table

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for L2Table

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

Formats the value using the given formatter.

impl Drop for L2Table

fn drop(&mut self)

Executes the destructor for this type.

impl Table for L2Table

const NAME: &'static str = "L2 table"

User-readable struct name.

const MAX_ENTRIES: usize = 262_144usize

Maximum allowable number of entries.

type InternalEntry = AtomicL2Entry

Internal type for each table entry.

type Entry = L2Entry

Externally visible type for each table entry.

fn from_data(data: Box<[AtomicL2Entry]>, header: &Header) -> Self

Create a new table with the given contents

fn entries(&self) -> usize

Number of entries.

fn get_ref(&self, index: usize) -> Option<&AtomicL2Entry>

Get the given entry (as reference).

fn get(&self, index: usize) -> L2Entry

Get the given entry (copied).

fn get_cluster(&self) -> Option<HostCluster>

Get this table’s (first) cluster in the image file.

fn get_offset(&self) -> Option<HostOffset>

Get this table’s offset in the image file.

fn set_cluster(&mut self, cluster: HostCluster)

Set this table’s (first) cluster in the image file (for writing).

fn unset_cluster(&mut self)

Remove the table’s association with any cluster in the image file.

fn is_modified(&self) -> bool

Check whether this table has been modified since it was last written.

fn clear_modified(&self)

Clear the modified flag.

fn set_modified(&self)

Set the modified flag.

fn cluster_bits(&self) -> u32

Return log2 of the cluster size.

fn byte_size(&self) -> usize

Table size in bytes.

fn cluster_count(&self) -> ClusterCount

Number of clusters used by this table.

async fn load<S: Storage>( image: &S, header: &Header, cluster: HostCluster, entries: usize, ) -> Result<Self>

Load a table from the image file.

async fn write<S: Storage>(&self, image: &S) -> Result<()>

Write a table to the image file.

async fn write_entry<S: Storage>(&self, image: &S, index: usize) -> Result<()>

Write at least the given single (modified) entry to the image file.