On Mon, Jun 08, 2015 at 05:42:15PM +0300, Sagi Grimberg wrote: > I wouldn't say this is about offloading bounce buffering to silicon. > The RDMA stack always imposed the alignment limitation as we can only > give a page lists to the devices. Other drivers (qlogic/emulex FC > drivers for example), use an _arbitrary_ SG lists where each element can > point to any {addr, len}. Those are drivers for protocols that support real SG lists. It seems only Infiniband and NVMe expose this silly limit. > >So please fix it in the proper layers > >first, > > I agree that we can take care of bounce buffering in the block layer > (or scsi for SG_IO) if the driver doesn't want to see any type of > unaligned SG lists. > > But do you think that it should come before the stack can support this? Yes, absolutely. The other thing that needs to come first is a proper abstraction for MRs instead of hacking another type into all drivers. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html