From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-cys01nam02on0064.outbound.protection.outlook.com ([104.47.37.64]:62976 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S969765AbdAFAlf (ORCPT ); Thu, 5 Jan 2017 19:41:35 -0500 Subject: Re: Enabling peer to peer device transactions for PCIe devices To: Jason Gunthorpe , Jerome Glisse References: <20170105183927.GA5324@gmail.com> <20170105190113.GA12587@obsidianresearch.com> <20170105195424.GB2166@redhat.com> <20170105200719.GB31047@obsidianresearch.com> <20170105201935.GC2166@redhat.com> <20170105224215.GA3855@obsidianresearch.com> <20170105232352.GB6426@redhat.com> <20170106003034.GB4670@obsidianresearch.com> CC: Jerome Glisse , "Deucher, Alexander" , "'linux-kernel@vger.kernel.org'" , "'linux-rdma@vger.kernel.org'" , "'linux-nvdimm@lists.01.org'" , "'Linux-media@vger.kernel.org'" , "'dri-devel@lists.freedesktop.org'" , "'linux-pci@vger.kernel.org'" , "Kuehling, Felix" , "Blinzer, Paul" , "Koenig, Christian" , "Suthikulpanit, Suravee" , "Sander, Ben" , , , From: Serguei Sagalovitch Message-ID: <26f86650-5302-0df2-9b51-dd967f3e5a7b@amd.com> Date: Thu, 5 Jan 2017 19:41:26 -0500 MIME-Version: 1.0 In-Reply-To: <20170106003034.GB4670@obsidianresearch.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 2017-01-05 07:30 PM, Jason Gunthorpe wrote: > ........ but I am opposed to > the idea we need two API paths that the *driver* has to figure out. > That is fundamentally not what I want as a driver developer. > > Give me a common API to convert '__user *' to a scatter list and pin > the pages. Completely agreed. IMHO there is no sense to duplicate the same logic everywhere as well as trying to find places where it is missing. Sincerely yours, Serguei Sagalovitch