[PATCH 1/3] rust: dma: be consistent in using the `coherent` nomenclature

Abdiel Janulgue posted 3 patches 8 months, 3 weeks ago
[PATCH 1/3] rust: dma: be consistent in using the `coherent` nomenclature
Posted by Abdiel Janulgue 8 months, 3 weeks ago
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.

Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
---
 rust/kernel/dma.rs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs
index 8cdc76043ee7..d3f448868457 100644
--- a/rust/kernel/dma.rs
+++ b/rust/kernel/dma.rs
@@ -89,15 +89,15 @@ 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);
 
-    /// This tells the DMA-mapping subsystem to suppress allocation failure reports (similarly to
+    /// Tells the DMA-mapping subsystem to suppress allocation failure reports (similarly to
     /// __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
     ///
-- 
2.43.0
Re: [PATCH 1/3] rust: dma: be consistent in using the `coherent` nomenclature
Posted by Andreas Hindborg 8 months, 1 week ago
"Abdiel Janulgue" <abdiel.janulgue@gmail.com> writes:

> 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.
>
> Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>
> ---
>  rust/kernel/dma.rs | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs
> index 8cdc76043ee7..d3f448868457 100644
> --- a/rust/kernel/dma.rs
> +++ b/rust/kernel/dma.rs
> @@ -89,15 +89,15 @@ 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

This and the next two edits has nothing to do with coherent/consistent
nomenclature. Please update the commit message to reflect that.


Best regards,
Andreas Hindborg
Re: [PATCH 1/3] rust: dma: be consistent in using the `coherent` nomenclature
Posted by Benno Lossin 8 months, 3 weeks ago
On Wed Mar 26, 2025 at 9:11 PM CET, Abdiel Janulgue wrote:
> 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.
>
> Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>

Reviewed-by: Benno Lossin <benno.lossin@proton.me>

---
Cheers,
Benno

> ---
>  rust/kernel/dma.rs | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)