Struct OperationId 

pub struct OperationId { /* private fields */ }

The name of one in-flight operation, carrying no claim on anything.

Returned by a push so a caller can refer to the operation it just queued – to cancel it, to correlate it, or to feed crate::contract::RingContract. It is Copy, has no Drop, and losing one is harmless.

A name, not a capability (D-71)

This deliberately carries no power to retrieve a payload. The ring hands a payload back only from the pop that observed its completion, which is what makes a use-after-free unrepresentable: there is no call that turns an identity into the memory an operation may still be using.

That is the same property Token::claim_if bought at runtime, and this buys it structurally. The retired claim_if took a crate::Completion rather than a usize precisely because a Completion has no public constructor, so the only proof the kernel has finished was one that had been popped; a caller-supplied integer would have let safe code free a buffer the kernel was still writing into. M28.4.1d.3 removed the call rather than the argument: the payload now comes back from the pop, so there is no second entry point to guard.

Handing an OperationId to a cancel stays safe for the reason it was always safe to pass a token’s id there: a cancel returns no memory.

Implementations

impl OperationId

pub fn user_data(&self) -> usize

The UserData value this operation carries.

The integer the kernel echoes back in its IORING_CQE. Useful as a cancel target and for a caller’s own correlation; it is not a handle to anything.

Trait Implementations

impl Clone for OperationId

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for OperationId

impl Debug for OperationId

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

Formats the value using the given formatter.

impl Display for OperationId

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

Formats the value using the given formatter.

impl Eq for OperationId

impl Hash for OperationId

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for OperationId

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for OperationId