Enum FixedMapping

pub(super) enum FixedMapping {
    ZeroDiscard,
    ZeroRetainAllocation,
    FullDiscard,
}

Possible mapping types for Qcow2::ensure_fixed_mapping().

Variants

ZeroDiscard

Make all clusters zero clusters, discarding previous allocations.

Note this breaks existing mapping information, which must be communicated somehow, for example by requiring mutable access to the Qcow2 object.

ZeroRetainAllocation

Make all clusters zero clusters, retaining previous allocations.

Retains previous data cluster allocations in the form of preallocated zero clusters, but cannot retain previously existing compressed cluster allocations. Because those mappings are not returned through the mapping interface, however, concurrent accesses should be reasonably safe.

(Writing to zeroed data cluster mappings will just have no effect.)

FullDiscard

Fully remove clusters’ mappings, allowing backing data to appear.

Note this breaks existing mapping information, which must be communicated somehow, for example by requiring mutable access to the Qcow2 object.

Trait Implementations

impl Clone for FixedMapping

fn clone(&self) -> FixedMapping

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FixedMapping

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

Formats the value using the given formatter.

impl PartialEq for FixedMapping

fn eq(&self, other: &FixedMapping) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for FixedMapping

impl Eq for FixedMapping

impl StructuralPartialEq for FixedMapping