Commit 9863f774 authored by Abdiel Janulgue's avatar Abdiel Janulgue Committed by Danilo Krummrich
Browse files

rust: dma: clarify wording and be consistent in `coherent` nomenclature 



In the kernel, `consistent` and `coherent` are used interchangeably for the
region described in this api. Stick with `coherent` nomenclature
to show that dma_alloc_coherent() is being used, in addition to improving
the clarity in the DMA mapping attributes documentation.

Reviewed-by: default avatarBenno Lossin <benno.lossin@proton.me>
Signed-off-by: default avatarAbdiel Janulgue <abdiel.janulgue@gmail.com>
Reviewed-by: default avatarAndreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250602085444.1925053-2-abdiel.janulgue@gmail.com


Signed-off-by: default avatarDanilo Krummrich <dakr@kernel.org>
parent 19272b37

rust/kernel/dma.rs

+5 −5
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ pub mod attrs { 
    /// Forces contiguous allocation of the buffer in physical memory.

    pub const DMA_ATTR_FORCE_CONTIGUOUS: Attrs = Attrs(bindings::DMA_ATTR_FORCE_CONTIGUOUS);



    /// This is a hint to the DMA-mapping subsystem that it's probably not worth the time to try

    /// Hints DMA-mapping subsystem that it's probably not worth the time to try

    /// to allocate memory to in a way that gives better TLB efficiency.

    pub const DMA_ATTR_ALLOC_SINGLE_PAGES: Attrs = Attrs(bindings::DMA_ATTR_ALLOC_SINGLE_PAGES);
@@ -97,7 +97,7 @@ pub mod attrs { 
    /// `__GFP_NOWARN`).

    pub const DMA_ATTR_NO_WARN: Attrs = Attrs(bindings::DMA_ATTR_NO_WARN);



    /// Used to indicate that the buffer is fully accessible at an elevated privilege level (and

    /// Indicates that the buffer is fully accessible at an elevated privilege level (and

    /// ideally inaccessible or at least read-only at lesser-privileged levels).

    pub const DMA_ATTR_PRIVILEGED: Attrs = Attrs(bindings::DMA_ATTR_PRIVILEGED);

}
@@ -105,7 +105,7 @@ pub mod attrs { 
/// An abstraction of the `dma_alloc_coherent` API.

///

/// This is an abstraction around the `dma_alloc_coherent` API which is used to allocate and map

/// large consistent DMA regions.

/// large coherent DMA regions.

///

/// A [`CoherentAllocation`] instance contains a pointer to the allocated region (in the

/// processor's virtual address space) and the device address which can be given to the device
@@ -115,7 +115,7 @@ pub mod attrs { 
/// # Invariants

///

/// For the lifetime of an instance of [`CoherentAllocation`], the `cpu_addr` is a valid pointer

/// to an allocated region of consistent memory and `dma_handle` is the DMA address base of

/// to an allocated region of coherent memory and `dma_handle` is the DMA address base of

/// the region.

// TODO

//
@@ -138,7 +138,7 @@ pub struct CoherentAllocation<T: AsBytes + FromBytes> { 
}



impl<T: AsBytes + FromBytes> CoherentAllocation<T> {

    /// Allocates a region of `size_of::<T> * count` of consistent memory.

    /// Allocates a region of `size_of::<T> * count` of coherent memory.

    ///

    /// # Examples

    ///