Struct KernelAsyncRing 

pub struct KernelAsyncRing { /* private fields */ }

A kernel async-I/O ring backed by an io_uring instance.

Implementations

impl KernelAsyncRing

pub fn new(entries: u32) -> Result<Self>

Create a ring with entries submission slots. Fails on kernels without io_uring (e.g. some containers) so callers can fall back to synchronous I/O.

pub unsafe fn prepare_read( &mut self, file: &File, buf: *mut u8, len: u32, offset: u64, user_data: u64, ) -> Result<()>

Queue a read of len bytes from file at offset into buf, tagged with user_data. Open file with open_for_async_read.

Safety

buf must remain valid and not move until the matching completion is reaped - the kernel writes into it asynchronously.

pub fn submit_and_wait(&mut self, want: u32) -> Result<u32>

Submit all queued ops and block until at least want complete.

pub fn reap(&mut self) -> Option<Completion>

Reap one completion if available.