Struct VirtqueueAvailableRing

#[repr(C, align(2))]
pub struct VirtqueueAvailableRing<const MAX_QUEUE_SIZE: usize> { /* private fields */ }

The Virtqueue available ring.

This struct is exposed to the VirtIO device as a means to share buffers (pointed to by descriptors of the VirtqueueDescriptors descriptors table) with the VirtIO device (host). It avoids the need for explicit locking by using two distinct rings, each undirectionally exchanging information about used buffers. When a new buffer is placed into the available ring, the VirtIO driver (guest) must increment idx to the index where it would place the next available descriptor pointer in the ring field. After such an update, the queue must inform the device about this change through a call to VirtIOTransport::queue_notify. Given that volatile writes cannot be reordered with respect to each other, changes to the available ring are guaranteed to be visible to the VirtIO device (host).

Trait Implementations

impl<const MAX_QUEUE_SIZE: usize> Default for VirtqueueAvailableRing<MAX_QUEUE_SIZE>

fn default() -> Self

Returns the “default value” for a type.