Re: [PATCH v1 14/16] x86/amd_gart: return error code from gart_map_sg()

[Robin Murphy <robin.murphy@xxxxxxx>]

On 2021-07-16 07:32, Christoph Hellwig wrote:
> On Thu, Jul 15, 2021 at 10:45:42AM -0600, Logan Gunthorpe wrote:
> > @@ -458,7 +460,7 @@ static int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents,
> >   	iommu_full(dev, pages << PAGE_SHIFT, dir);
> >   	for_each_sg(sg, s, nents, i)
> >   		s->dma_address = DMA_MAPPING_ERROR;
> > -	return 0;
> > +	return ret;
>
> While we're at it - setting the ->dma_address to DMA_MAPPING_ERROR is
> not part of the ->map_sg calling convention.  Might be worth to fix
> up while we're at it.

Especially since it's not even zeroing dma_length, which at least is a 
documented indicator of validity (even if it's not strictly defined for 
failure cases either).

Robin.