From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15A8DC43217 for ; Wed, 29 Sep 2021 23:28:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB38A61527 for ; Wed, 29 Sep 2021 23:28:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347139AbhI2Xag (ORCPT ); Wed, 29 Sep 2021 19:30:36 -0400 Received: from ale.deltatee.com ([204.191.154.188]:60536 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245025AbhI2Xaf (ORCPT ); Wed, 29 Sep 2021 19:30:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:In-Reply-To:MIME-Version:Date: Message-ID:From:References:Cc:To:content-disposition; bh=NYyTaf27EInHhX60ljYBoeATyLjSGs1NVod8tkafPeY=; b=EWozigDhXaXheIOw3+nHDtN4G6 eFSOZ5q8F/2nZpK2IzAxIYKC4S9LDPF19Ym9gqJ8EQH2CYYB0eZPhBVZFPNgllppCzKBbLElzRGxI mjOi6SpfbjHBdpYGGFSewfSUDyh7wanUxSZDj+03pzSkYeqm/aIZoPsTswsfEkqn0df+fg2/B8ZNP eLLZtU513+UpUEKzyBAWGXBYdkvhYZyf3h7NVOsMnsbHERQjNOXVhBo5XV1nMbOTXEnvBbdqySQqu xIv45bM6TtjludpPxa83ejx2eBYBOoqqEyohv4QngbqSVtzDM3nLZqpla5/bYOnKPfhp+diVGMaME v4VgN3yw==; Received: from s0106a84e3fe8c3f3.cg.shawcable.net ([24.64.144.200] helo=[192.168.0.10]) by ale.deltatee.com with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1mVj0C-0008Eg-58; Wed, 29 Sep 2021 17:28:41 -0600 To: Jason Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Stephen Bates , Christoph Hellwig , Dan Williams , =?UTF-8?Q?Christian_K=c3=b6nig?= , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Bjorn Helgaas , Ira Weiny , Robin Murphy , Martin Oliveira , Chaitanya Kulkarni References: <20210916234100.122368-1-logang@deltatee.com> <20210928200216.GW3544071@ziepe.ca> <06d75fcb-ce8b-30a5-db36-b6c108460d3d@deltatee.com> <20210929232147.GD3544071@ziepe.ca> From: Logan Gunthorpe Message-ID: <93f56919-03ee-8326-10ee-8fbd9078b8e0@deltatee.com> Date: Wed, 29 Sep 2021 17:28:38 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <20210929232147.GD3544071@ziepe.ca> Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 24.64.144.200 X-SA-Exim-Rcpt-To: ckulkarnilinux@gmail.com, martin.oliveira@eideticom.com, robin.murphy@arm.com, ira.weiny@intel.com, helgaas@kernel.org, jianxin.xiong@intel.com, dave.hansen@linux.intel.com, jason@jlekstrand.net, dave.b.minturn@intel.com, andrzej.jakowski@intel.com, daniel.vetter@ffwll.ch, willy@infradead.org, ddutile@redhat.com, jhubbard@nvidia.com, christian.koenig@amd.com, dan.j.williams@intel.com, hch@lst.de, sbates@raithlin.com, iommu@lists.linux-foundation.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, jgg@ziepe.ca X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [PATCH v3 00/20] Userspace P2PDMA with O_DIRECT NVMe devices X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-09-29 5:21 p.m., Jason Gunthorpe wrote: > On Wed, Sep 29, 2021 at 03:50:02PM -0600, Logan Gunthorpe wrote: >> >> >> On 2021-09-28 2:02 p.m., Jason Gunthorpe wrote: >>> On Thu, Sep 16, 2021 at 05:40:40PM -0600, Logan Gunthorpe wrote: >>>> Hi, >>>> >>>> This patchset continues my work to add userspace P2PDMA access using >>>> O_DIRECT NVMe devices. My last posting[1] just included the first 13 >>>> patches in this series, but the early P2PDMA cleanup and map_sg error >>>> changes from that series have been merged into v5.15-rc1. To address >>>> concerns that that series did not add any new functionality, I've added >>>> back the userspcae functionality from the original RFC[2] (but improved >>>> based on the original feedback). >>> >>> I really think this is the best series yet, it really looks nice >>> overall. I know the sg flag was a bit of a debate at the start, but it >>> serves an undeniable purpose and the resulting standard DMA APIs 'just >>> working' is really clean. >> >> Actually, so far, nobody has said anything negative about using the SG flag. >> >>> There is more possible here, we could also pass the new GUP flag in the >>> ib_umem code.. >> >> Yes, that would be very useful. > > You might actually prefer to do that then the bio changes to get the > infrastructur merged as it seems less "core" I'm a little bit more concerned about my patch set growing too large. It's already at 20 patches and I think I'll need to add a couple more based on the feedback you've already provided. So I'm leaning toward pushing more functionality as future work. Logan