Struct disk::qcow::refcount::RefCount

pub struct RefCount {
    ref_table: VecCache<u64>,
    refcount_table_offset: u64,
    refblock_cache: CacheMap<VecCache<u16>>,
    refcount_block_entries: u64,
    cluster_size: u64,
    max_valid_cluster_offset: u64,
}

Represents the refcount entries for an open qcow file.

Fields

ref_table: VecCache<u64>

refcount_table_offset: u64

refblock_cache: CacheMap<VecCache<u16>>

refcount_block_entries: u64

cluster_size: u64

max_valid_cluster_offset: u64

Implementations

impl RefCount

pub fn new( raw_file: &mut QcowRawFile, refcount_table_offset: u64, refcount_table_entries: u64, refcount_block_entries: u64, cluster_size: u64 ) -> Result<RefCount>

Creates a RefCount from file, reading the refcount table from refcount_table_offset. refcount_table_entries specifies the number of refcount blocks used by this image. refcount_block_entries indicates the number of refcounts in each refcount block. Each refcount table entry points to a refcount block.

pub fn refcounts_per_block(&self) -> u64

Returns the number of refcounts per block.

pub fn max_valid_cluster_offset(&self) -> u64

Returns the maximum valid cluster offset in the raw file for this refcount table.

pub fn set_cluster_refcount( &mut self, raw_file: &mut QcowRawFile, cluster_address: u64, refcount: u16, new_cluster: Option<(u64, VecCache<u16>)> ) -> Result<Option<u64>, Error>

Returns NeedNewCluster if a new cluster needs to be allocated for refcounts. If an existing cluster needs to be read, NeedCluster(addr) is returned. The Caller should allocate a cluster or read the required one and call this function again with the cluster. On success, an optional address of a dropped cluster is returned. The dropped cluster can be reused for other purposes.

pub fn flush_blocks(&mut self, raw_file: &mut QcowRawFile) -> Result<()>

Flush the dirty refcount blocks. This must be done before flushing the table that points to the blocks.

pub fn flush_table(&mut self, raw_file: &mut QcowRawFile) -> Result<bool>

Flush the refcount table that keeps the address of the refcounts blocks. Returns true if the table changed since the previous flush_table() call.

pub fn get_cluster_refcount( &mut self, raw_file: &mut QcowRawFile, address: u64 ) -> Result<u16, Error>

Gets the refcount for a cluster with the given address.

fn get_refcount_index(&self, address: u64) -> (usize, usize)

Trait Implementations

impl Debug for RefCount

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

Formats the value using the given formatter.