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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1FA8FCFD658 for ; Wed, 7 Jan 2026 16:02:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=tuZlZNCAeheCdaAvbdX1OyiCZgRK0BeozeF6MxCmlhA=; b=T7TKJK8gQnUKYEub8O0tbWB2g0 QBDUKO6vBIY5OBdWqQScLq5Xb0YccLqB/i+K5vbbCXhQkBdGzIxgf2DInoNhz1AKl72JCt7+YcN6S Btx5dnaaeW/v98SqkBsLbS8iUbFTBtI34bUHKhzukCtKXYdGeDtnGecRO5bu+MwmPjX50eQMPwyMS cQcF/f40/Q3a1UUO3EA6bfsGX/IOW0weDt2afMGFm3YP7dPyDTlX3XH9Yjttdemlu2I2vYHzG3m7i 96EO4ZJftlHzCiU1VV0thTJEZ+Vl8AfGFgApV7hMhLoUzM4Q1vAjKd6DDtzkSpVqPcSMd/mkDknCL ajAphf2A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vdVz0-0000000FDdT-2ssr; Wed, 07 Jan 2026 16:02:02 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vdVyy-0000000FDcC-07u6 for linux-nvme@lists.infradead.org; Wed, 07 Jan 2026 16:02:01 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id D9186227A87; Wed, 7 Jan 2026 17:01:51 +0100 (CET) Date: Wed, 7 Jan 2026 17:01:51 +0100 From: Christoph Hellwig To: Christian =?iso-8859-1?Q?K=F6nig?= Cc: Ming Lei , Christoph Hellwig , Pavel Begunkov , linux-block@vger.kernel.org, io-uring@vger.kernel.org, Vishal Verma , tushar.gohad@intel.com, Keith Busch , Jens Axboe , Sagi Grimberg , Alexander Viro , Christian Brauner , Andrew Morton , Sumit Semwal , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Subject: Re: [RFC v2 01/11] file: add callback for pre-mapping dmabuf Message-ID: <20260107160151.GA21887@lst.de> References: <74d689540fa200fe37f1a930165357a92fe9e68c.1763725387.git.asml.silence@gmail.com> <7b2017f4-02a3-482a-a173-bb16b895c0cb@amd.com> <20251204110709.GA22971@lst.de> <0571ca61-7b17-4167-83eb-4269bd0459fe@amd.com> <20251204131025.GA26860@lst.de> <754b4cc9-20ab-4d87-85bf-eb56be058856@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <754b4cc9-20ab-4d87-85bf-eb56be058856@amd.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260107_080200_217101_59D9F131 X-CRM114-Status: GOOD ( 16.45 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Wed, Jan 07, 2026 at 04:56:05PM +0100, Christian König wrote: > > But I am wondering why not make it as one subsystem interface, such as nvme > > ioctl, then the whole implementation can be simplified a lot. It is reasonable > > because subsystem is exactly the side for consuming/importing the dma-buf. > > Yeah that it might be better if it's more nvme specific came to me as well. The feature is in no way nvme specific. nvme is just the initial underlying driver. It makes total sense to support this for any high performance block device, and to pass it through file systems.