On 04-Jan-19 05:51, Jason Gunthorpe wrote: > Also you can't mmap to user space dma_coherent memory, so this entire > thing needs reworking to use non-coherent memory and proper barriers > like all the other drivers. Hi Jason, Why can't coherent DMA memory be mmapped to userspace? (BTW, looks like cxgb4 does that). Also, if the streaming DMA mapping is used, how can the userspace call dma_sync_*? As far as I can tell, the userspace udma_*_device_barrier doesn't seem to replace it.
