On Tue, Jan 15, 2019 at 05:23:22PM +0100, Joerg Roedel wrote:
> Right, I thought about that too, but didn't find a generic way to check
> for all the cases. There are various checks that could be done:
>
> 1) Check if SWIOTLB is initialized at all, if not, return
> SIZE_MAX as the l
On Tue, Jan 15, 2019 at 02:37:54PM +0100, Christoph Hellwig wrote:
> > +size_t dma_direct_max_mapping_size(struct device *dev)
> > +{
> > + /*
> > +* Return the minimum of the direct DMA limit and the SWIOTLB limit.
> > +* Since direct DMA has no limit, it is fine to just return the SWIOT
From: Joerg Roedel
The function returns the maximum size that can be mapped
using DMA-API functions. The patch also adds the
implementation for direct DMA and a new dma_map_ops pointer
so that other implementations can expose their limit.
Signed-off-by: Joerg Roedel
---
include/linux/dma-mappi
> +size_t dma_direct_max_mapping_size(struct device *dev)
> +{
> + /*
> + * Return the minimum of the direct DMA limit and the SWIOTLB limit.
> + * Since direct DMA has no limit, it is fine to just return the SWIOTLB
> + * limit.
> + */
> + return swiotlb_max_mapping_siz
