Re: [PATCH 2/2] gpu: nova-core: falcon: use I/O projection to check transfer bounds

On Fri Jul 24, 2026 at 8:10 PM CEST, John Hubbard wrote:
> Sort of "conceptually pre-existing" problem, but "handle" doesn't
> quite work as a name, because handles are supposed to be opaque
> items that one just uses to find and refer to things.

This is inherited from the C API where from its perspective the returned base
DMA address of the allocation actually serves as a handle.

In Rust the actual handle is represented by different types with different
invariants and hence capabilties.

(For instance, dma::CoherentBox does not expose the DMA address at all, and
hence provides access to its contents through a direct mutable reference,
whereas dma::CoherentHandle only provides access to the DMA address and does not
have a CPU virtual mapping; dma::Coherent provides access to both.)

Both dma::Coherent and dma::CoherentHandle have a dma_handle() method which
provides access to the DMA address; this naming was taken over from the C API.

Given that the base DMA address serving as a handle from the perspective of the
C API is just an implementation detail, we should probably just rename this
method to dma_address().