Struct DeviceTestDmaClient

pub struct DeviceTestDmaClient<C>
where
    C: DeviceTestDmaClientCallbacks,
{ /* private fields */ }

A DMA client that uses a [PagePoolAllocator] as the backing. It can be customized through the use of DeviceTestDmaClientCallbacks to modify its behaviour for testing purposes.

Example

use std::sync::Arc;
use user_driver::DmaClient;
use user_driver_emulated_mock::DeviceTestDmaClient;
use page_pool_alloc::PagePoolAllocator;

struct MyCallbacks;
impl user_driver_emulated_mock::DeviceTestDmaClientCallbacks for MyCallbacks {
    fn allocate_dma_buffer(
        &self,
        allocator: &page_pool_alloc::PagePoolAllocator,
        total_size: usize,
    ) -> anyhow::Result<user_driver::memory::MemoryBlock> {
        // Custom test logic here, for example:
        anyhow::bail!("allocation failed for testing");
    }

    fn attach_pending_buffers(
        &self,
        allocator: &page_pool_alloc::PagePoolAllocator,
    ) -> anyhow::Result<Vec<user_driver::memory::MemoryBlock>> {
        // Custom test logic here, for example:
        anyhow::bail!("attachment failed for testing");
    }
}

// Use the above in a test ...
fn test_dma_client() {
    let pages = 1000;
    let device_test_memory = user_driver_emulated_mock::DeviceTestMemory::new(
        pages,
        true,
        "test_dma_client",
    );
    let page_pool_allocator = device_test_memory.dma_client();
    let dma_client = DeviceTestDmaClient::new(page_pool_allocator, MyCallbacks);

    // Use dma_client in tests...
    assert!(dma_client.allocate_dma_buffer(4096).is_err());
}

Implementations

impl<C: DeviceTestDmaClientCallbacks> DeviceTestDmaClient<C>

pub fn new(inner: Arc<PagePoolAllocator>, callbacks: C) -> Self

Creates a new DeviceTestDmaClient with the given inner allocator.

Trait Implementations

impl<C: DeviceTestDmaClientCallbacks> DmaClient for DeviceTestDmaClient<C>

fn allocate_dma_buffer(&self, total_size: usize) -> Result<MemoryBlock>

Allocate a new DMA buffer. This buffer must be zero initialized.

fn attach_pending_buffers(&self) -> Result<Vec<MemoryBlock>>

Attach all previously allocated memory blocks.

impl<C> Inspect for DeviceTestDmaClient<C>

where C: DeviceTestDmaClientCallbacks,

fn inspect(&self, req: Request<'_>)

Inspects the object.