On 19/04/2020 22:25, Joerg Roedel wrote:
> On Sun, Apr 19, 2020 at 10:00:58AM +0200, Christoph Hellwig wrote:
>> The difference is that NULL ops mean imply the direct mapping is always
>> used, dma_ops_bypass means a direct mapping is used if no bounce buffering
>> using swiotlb is needed,
On Sun, Apr 19, 2020 at 10:00:58AM +0200, Christoph Hellwig wrote:
> The difference is that NULL ops mean imply the direct mapping is always
> used, dma_ops_bypass means a direct mapping is used if no bounce buffering
> using swiotlb is needed, which should also answer your first question.
> The
On Sat, Apr 18, 2020 at 02:42:05PM +0200, Joerg Roedel wrote:
> Hi Christoph,
>
> On Tue, Apr 14, 2020 at 02:25:05PM +0200, Christoph Hellwig wrote:
> > +static inline bool dma_map_direct(struct device *dev,
> > + const struct dma_map_ops *ops)
> > +{
> > + if (likely(!ops))
> > +
Hi Christoph,
On Tue, Apr 14, 2020 at 02:25:05PM +0200, Christoph Hellwig wrote:
> +static inline bool dma_map_direct(struct device *dev,
> + const struct dma_map_ops *ops)
> +{
> + if (likely(!ops))
> + return true;
> + if (!dev->dma_ops_bypass)
> +
On Tue, Apr 14, 2020 at 02:25:05PM +0200, Christoph Hellwig wrote:
> Several IOMMU drivers have a bypass mode where they can use a direct
> mapping if the devices DMA mask is large enough. Add generic support
> to the core dma-mapping code to do that to switch those drivers to
> a common
Several IOMMU drivers have a bypass mode where they can use a direct
mapping if the devices DMA mask is large enough. Add generic support
to the core dma-mapping code to do that to switch those drivers to
a common solution.
Signed-off-by: Christoph Hellwig
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include/linux/device.h | 6
