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 C3FC9C433F5 for ; Wed, 29 Sep 2021 23:28:54 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 71C6A61507 for ; Wed, 29 Sep 2021 23:28:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 71C6A61507 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=deltatee.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 056AA94006D; Wed, 29 Sep 2021 19:28:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F213394003A; Wed, 29 Sep 2021 19:28:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DC1F594006D; Wed, 29 Sep 2021 19:28:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0204.hostedemail.com [216.40.44.204]) by kanga.kvack.org (Postfix) with ESMTP id C616B94003A for ; Wed, 29 Sep 2021 19:28:53 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 7010739F36 for ; Wed, 29 Sep 2021 23:28:53 +0000 (UTC) X-FDA: 78642203346.07.23F6986 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) by imf19.hostedemail.com (Postfix) with ESMTP id 35350B00018B for ; Wed, 29 Sep 2021 23:28:53 +0000 (UTC) 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) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=deltatee.com header.s=20200525 header.b=EWozigDh; spf=pass (imf19.hostedemail.com: domain of logang@deltatee.com designates 204.191.154.188 as permitted sender) smtp.mailfrom=logang@deltatee.com; dmarc=pass (policy=none) header.from=deltatee.com X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 35350B00018B X-Stat-Signature: 6utje4c6wjibofp97r4937j5j8w36jt5 X-HE-Tag: 1632958133-142026 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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