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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E951EC433EF for ; Tue, 11 Jan 2022 23:02:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7EB656B00EA; Tue, 11 Jan 2022 18:02:48 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 79AE26B00EB; Tue, 11 Jan 2022 18:02:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6B2216B00EC; Tue, 11 Jan 2022 18:02:48 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0092.hostedemail.com [216.40.44.92]) by kanga.kvack.org (Postfix) with ESMTP id 5C8DD6B00EA for ; Tue, 11 Jan 2022 18:02:48 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 1249E8248D52 for ; Tue, 11 Jan 2022 23:02:48 +0000 (UTC) X-FDA: 79019532816.18.83D034E Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) by imf17.hostedemail.com (Postfix) with ESMTP id AA07340010 for ; Tue, 11 Jan 2022 23:02:47 +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=JGlaIoL3JiUKm69gr69makSNy4JbMH4jchaLUqVIQxs=; b=NM2fx5bsTE7zC6hwXw0Pgx4Buo YnfVscCdiluO/KndLwpHCA5V85udbr7MzWgEb1jg38WkJSJ8fL3OyoqyyqL4jqzpO8Pla/mmcgX9W VJ7W4VkXNJiQARYHA3wa32V1flSLWj92lPbrgdvrnpN3B7d/ng3u6q7Izch764pw8iqYH7LVLwavR 9DYYHGpHiwJy0jdCORXgA+Mo7xeugu7AqTrSBASKABIReHfGXjUj6rWyn+3zZe7NXnGeToD2PVPbh 9LKn87e0XzYUAwW/Ryxeab2v22Vg57Ssl+z8R3d88jdSx39zEXB+uAT7iAZZTtXcR3vfLHVYnyNhp 88IglYGA==; Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1n7QA9-009o9j-CV; Tue, 11 Jan 2022 16:02:46 -0700 To: Jason Gunthorpe Cc: Matthew Wilcox , linux-kernel@vger.kernel.org, Christoph Hellwig , Joao Martins , John Hubbard , Ming Lei , linux-block@vger.kernel.org, netdev@vger.kernel.org, linux-mm@kvack.org, linux-rdma@vger.kernel.org, dri-devel@lists.freedesktop.org, nvdimm@lists.linux.dev References: <20220111004126.GJ2328285@nvidia.com> <20220111150142.GL2328285@nvidia.com> <20220111202159.GO2328285@nvidia.com> <20220111225713.GS2328285@nvidia.com> From: Logan Gunthorpe Message-ID: Date: Tue, 11 Jan 2022 16:02:44 -0700 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: <20220111225713.GS2328285@nvidia.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: nvdimm@lists.linux.dev, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-block@vger.kernel.org, ming.lei@redhat.com, jhubbard@nvidia.com, joao.m.martins@oracle.com, hch@lst.de, linux-kernel@vger.kernel.org, willy@infradead.org, jgg@nvidia.com X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: Phyr Starter X-SA-Exim-Version: 4.2.1 (built Sat, 13 Feb 2021 17:57:42 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: AA07340010 X-Stat-Signature: jex6m8r7zyhyse8yf7itb4t3y8a58fi3 Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=deltatee.com header.s=20200525 header.b=NM2fx5bs; spf=pass (imf17.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-HE-Tag: 1641942167-441245 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 2022-01-11 3:57 p.m., Jason Gunthorpe wrote: > On Tue, Jan 11, 2022 at 03:09:13PM -0700, Logan Gunthorpe wrote: > >> Either that, or we need a wrapper that allocates an appropriately >> sized SGL to pass to any dma_map implementation that doesn't support >> the new structures. > > This is what I think we should do. If we start with RDMA then we can > motivate the 4 main server IOMMU drivers to get updated ASAP, then it > can acceptably start to spread to other users. I suspect the preferred path forward is for the IOMMU drivers that don't use dma-iommu should be converted to use it. Then anything we do to dma-iommu will be applicable to the IOMMU drivers. Better than expecting them to implement a bunch of new functionality themselves. Logan