Method append_data_cluster

block/src/qcow/mod.rs:1622–1627

Allocate and initialize a new data cluster. Returns the offset of the cluster into the file on success.

(&mut self, initial_data: Option<Vec<u8>>)

    // Allocate and initialize a new data cluster. Returns the offset of the
    // cluster into the file on success.
    fn append_data_cluster(&mut self, initial_data: Option<Vec<u8>>) -> std::io::Result<u64> {
        let new_addr: u64 = self.get_new_cluster(initial_data)?;
        // The cluster refcount starts at one indicating it is used but doesn't need COW.
        self.set_cluster_refcount_track_freed(new_addr, 1)?;
        Ok(new_addr)
    }

    // Returns true if the cluster containing `address` is already allocated.
    fn cluster_allocated(&mut self, address: u64) -> std::io::Result<bool> {