Re: [PATCH 2/7] OF: Simplify DMA range calculations

[Jason Gunthorpe]

On Wed, Nov 29, 2023 at 05:42:59PM +0000, Robin Murphy wrote:
> Juggling start, end, and size values for a range is somewhat redundant
> and a little hard to follow. Consolidate down to just using inclusive
> start and end, which saves us worrying about size overflows for full
> 64-bit ranges (note that passing a potentially-overflowed value through
> to arch_setup_dma_ops() is benign for all current implementations, and
> this is working towards removing that anyway).

In iommu code I've been trying to use consistent language with other
parts of the kernel like interval tree and maple tree:

 * In this file the term 'last' indicates an inclusive and closed interval, eg
 * [0,0] refers to a single PFN. 'end' means an open range, eg [0,0) refers to
 * no PFNs.

Here I think you've swapped end to mean last?

Regardless the change looks correct

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason