On Tue, 13 Jul 2010 05:14:21 -0700 Zach Pfeffer <zpfeffer@xxxxxxxxxxxxxx> wrote: > > You mean that you want to specify this alignment attribute every time > > you create an IOMMU mapping? Then you can set segment_boundary_mask > > every time you create an IOMMU mapping. It's odd but it should work. > > Kinda. I want to forget about IOMMUs, devices and CPUs. I just want to > create a mapping that has the alignment I specify, regardless of the > mapper. The mapping is created on a VCM and the VCM is associated with > a mapper: a CPU, an IOMMU'd device or a direct mapped device. Sounds like you can do the above with the combination of the current APIs, create a virtual address and then an I/O address. The above can't be a reason to add a new infrastructure includes more than 3,000 lines. > > Another possible solution is extending struct dma_attrs. We could add > > the alignment attribute to it. > > That may be useful, but in the current DMA-API may be seen as > redundant info. If there is real requirement, we can extend the DMA-API. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>