On 13.11.2019 22:11, David Miller wrote: > From: Laurentiu Tudor <laurentiu.tu...@nxp.com> > Date: Wed, 13 Nov 2019 12:24:17 +0000 > >> From: Laurentiu Tudor <laurentiu.tu...@nxp.com> >> >> This series introduces a few new dma unmap and sync api variants that, >> on top of what the originals do, return the virtual address >> corresponding to the input dma address. In order to do that a new dma >> map op is added, .get_virt_addr that takes the input dma address and >> returns the virtual address backing it up. >> The second patch adds an implementation for this new dma map op in the >> generic iommu dma glue code and wires it in. >> The third patch updates the dpaa2-eth driver to use the new apis. > > The driver should store the mapping in it's private software state if > it needs this kind of conversion.
On this hardware there's no way of conveying additional frame information, such as original va/pa behind the dma address. We have also pondered on the idea of keeping this in some kind of data structure but could not find a lock-less solution which obviously would bring performance to the ground. I'll let my colleagues maintaining these ethernet drivers to get into more details, if required. --- Best Regards, Laurentiu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
