On 28/06/2022 12:27, John Garry via iommu wrote:
On 28/06/2022 12:23, Robin Murphy wrote:
+
+ size_t
+ dma_opt_mapping_size(struct device *dev);
+
+Returns the maximum optimal size of a mapping for the device.
Mapping large
+buffers may take longer so device drivers are advised to limit t
On 28/06/2022 12:23, Robin Murphy wrote:
+
+ size_t
+ dma_opt_mapping_size(struct device *dev);
+
+Returns the maximum optimal size of a mapping for the device. Mapping
large
+buffers may take longer so device drivers are advised to limit total DMA
+streaming mappings length to the return
On 2022-06-27 16:25, John Garry wrote:
Streaming DMA mapping involving an IOMMU may be much slower for larger
total mapping size. This is because every IOMMU DMA mapping requires an
IOVA to be allocated and freed. IOVA sizes above a certain limit are not
cached, which can have a big impact on DMA
Streaming DMA mapping involving an IOMMU may be much slower for larger
total mapping size. This is because every IOMMU DMA mapping requires an
IOVA to be allocated and freed. IOVA sizes above a certain limit are not
cached, which can have a big impact on DMA mapping performance.
Provide an API for
