Hi I'd like to discuss the topic of how best to enable DMAs between PCIe devices in the Linux kernel. There have been many attempts to add to the kernel the ability to DMA between two PCIe devices. However, to date, none of these have been accepted. However as PCIe devices like NICs, NVMe SSDs and GPGPUs continue to get faster the desire to move data directly between these devices (as opposed to having to using a temporary buffer in system memory) is increasing. Out of tree solutions like GPU-Direct are one illustration of the popularity of this functionality. A recent discussion on this topic provides a good summary of where things stand [1]. I would like to propose a session at LFS/MM to discuss some of the different use cases for these P2P DMAs and also to discuss the pros and cons of these approaches. The desire would be to try and form a consensus on how best to move forward to an upstreamable solution to this problem. In addition I would also be interested in participating in the following topics: * Anything related to PMEM and DAX. * Integrating the block-layer polling capability into file-systems. * New feature integration into the NVMe driver (e.g. fabrics, CMBs, IO tags etc.) Cheers Stephen [1] http://marc.info/?l=linux-pci&m=147976059431355&w=2 (and subsequent thread). -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
