Struct DmaSubSlice 

pub struct DmaSubSlice<'a, T: ImmutableFromIntoBytes> { /* private fields */ }

An immutable buffer that can be safely used for read-only DMA operations, created from a SubSlice describing an active range in a larger buffer.

Creating a DmaSubSlice over a SubSlice ensures that all prior Rust writes to the active region of this slice are observable by any DMA operations initiated through an MMIO write operation, where that MMIO write is performed after constructing the DmaSubSlice.

For this guarantee to hold, the DmaSubSlice struct must exist for the duration of the entire DMA operation, until the Rust program has observed that the operation is complete (such as by reading a status bit in memory or an MMIO register).

DmaSubSlice wraps an immutable, shared Rust slice reference. As such, its contents must not be modified by the DMA operation. For a DMA operation that may write to the supplied buffer, use DmaSubSliceMut instead.

Implementations

impl<'a, T: ImmutableFromIntoBytes> DmaSubSlice<'a, T>

pub fn new( sub_slice: SubSlice<'_, T>, fence: impl DmaFence, ) -> DmaSubSlice<'_, T>

Create a DmaSubSlice from a shared, immutable Rust slice.

This function uses the supplied fence object to ensure that all prior writes to slice are exposed to any DMA operations initiated by an MMIO read or write operation after this function returns, and which finish before the resulting DmaSubSlice is dropped.

pub fn as_ptr(&self) -> *const T

Returns the pointer to the first element of the currently accessible portion of the wrapped SubSlice.

pub fn len(&self) -> usize

Returns the length of the currently accessible range of the wrapped SubSlice.

pub fn as_sub_slice(&self) -> SubSlice<'a, T>

Retrieve the wrapped SubSlice.

Trait Implementations

impl<'a, T: Debug + ImmutableFromIntoBytes> Debug for DmaSubSlice<'a, T>

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

Formats the value using the given formatter.