[PATCH v2 3/3] iommu: Add a kdoc to iommu_unmap()

[Liviu Dudau]

On Mon, Nov 04, 2024 at 01:41:31PM -0400, Jason Gunthorpe wrote:
> Describe the most conservative version of the driver implementations.
> All drivers should support this.
> 
> Many drivers support extending the range if a large page is hit, but
> let's not make that officially approved API. The main point is to
> document explicitly that split is not supported.
> 
> Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
> ---
>  drivers/iommu/iommu.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 83c8e617a2c588..d3cf7cc69c797c 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -2586,6 +2586,20 @@ static size_t __iommu_unmap(struct iommu_domain *domain,
>  	return unmapped;
>  }
>  
> +/**
> + * iommu_unmap() - Remove mappings from a range of IOVA
> + * @domain: Domain to manipulate
> + * @iova: IO virtual address to start
> + * @len: Length of the range starting from @iova
> + *
> + * iommu_unmap() will remove a translation created by iommu_map(). It cannot
> + * subdivide a mapping created by iommu_map(), so it should be called with IOVA
> + * ranges that match what was passed to iommu_map(). The range can aggregate
> + * contiguous iommu_map() calls so long as no individual range is split.
> + *
> + * Returns: Number of bytes of IOVA unmapped. iova + res will be the point
> + * unmapping stopped.

I guess 'res' is the return value here. Not my default name for the variable,
worth replacing it with "return value" ?

Regardless of the acceptance of this nit:

Reviewed-by: Liviu Dudau <liviu.dudau at arm.com>

Best regards,
Liviu

> + */
>  size_t iommu_unmap(struct iommu_domain *domain,
>  		   unsigned long iova, size_t size)
>  {
> -- 
> 2.43.0
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯