Trait vhost::vdpa::VhostVdpa

source · [−]
pub trait VhostVdpa: VhostBackend {
    fn get_device_id(&self) -> Result<u32>;

    fn get_status(&self) -> Result<u8>;

    fn set_status(&self, status: u8) -> Result<()>;

    fn get_config(&self, offset: u32, buffer: &mut [u8]) -> Result<()>;

    fn set_config(&self, offset: u32, buffer: &[u8]) -> Result<()>;

    fn set_vring_enable(&self, queue_index: usize, enabled: bool) -> Result<()>;

    fn get_vring_num(&self) -> Result<u16>;

    fn set_config_call(&self, fd: &EventFd) -> Result<()>;

    fn get_iova_range(&self) -> Result<VhostVdpaIovaRange>;

    fn dma_map(
        &self, 
        iova: u64, 
        size: u64, 
        vaddr: *const u8, 
        readonly: bool
    ) -> Result<()>;

    fn dma_unmap(&self, iova: u64, size: u64) -> Result<()>;
}
Expand description

Trait to control vhost-vdpa backend drivers.

vDPA (virtio Data Path Acceleration) devices has datapath compliant with the virtio specification and the control path is vendor specific. vDPA devices can be both physically located on the hardware or emulated by software.

Compared to vhost acceleration, vDPA offers more control over the device lifecycle. For this reason, the vhost-vdpa interface extends the vhost API, offering additional APIs for controlling the device (e.g. changing the state or accessing the configuration space

Required methods

Get the device id. The device ids follow the same definition of the device id defined in virtio-spec.

Get the status. The status bits follow the same definition of the device status defined in virtio-spec.

Set the status. The status bits follow the same definition of the device status defined in virtio-spec.

Arguments
  • status - Status bits to set

Get the device configuration.

Arguments
  • offset - Offset in the device configuration space
  • buffer - Buffer for configuration data

Set the device configuration.

Arguments
  • offset - Offset in the device configuration space
  • buffer - Buffer for configuration data

Set the status for a given vring.

Arguments
  • queue_index - Index of the queue to enable/disable.
  • enabled - true to enable the vring, false to disable it.

Get the maximum number of descriptors in the vring supported by the device.

Set the eventfd to trigger when device configuration change.

Arguments
  • fd - EventFd to trigger.

Get the valid I/O virtual addresses range supported by the device.

Map DMA region.

Arguments
  • iova - I/O virtual address.
  • size - Size of the I/O mapping.
  • vaddr - Virtual address in the current process.
  • readonly - true if the region is read-only, false if reads and writes are allowed.

Unmap DMA region.

Arguments
  • iova - I/O virtual address.
  • size - Size of the I/O mapping.

Implementors