Re: [RFC][PATCH] dma-mapping: align default segment_boundary_mask with dma_mask

[Nicolin Chen]

Hi Christoph,

On Mon, Mar 16, 2020 at 01:48:50PM +0100, Christoph Hellwig wrote:
> On Fri, Mar 13, 2020 at 05:00:07PM -0700, Nicolin Chen wrote:
> > @@ -736,7 +736,7 @@ static inline unsigned long dma_get_seg_boundary(struct device *dev)
> >  {
> >  	if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
> >  		return dev->dma_parms->segment_boundary_mask;
> > -	return DMA_BIT_MASK(32);
> > +	return (unsigned long)dma_get_mask(dev);
> 
> Just thinking out loud after my reply - shouldn't we just return ULONG_MAX
> by default here to mark this as no limit?

Yea, ULONG_MAX (saying no limit) sounds good to me.