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 DDB0FD1CDA1 for ; Tue, 22 Oct 2024 06:05:00 +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-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=lfBoMYEB4g/sFrXbLKisl4NtwVnJb6lg1S7T+bahiA0=; b=T0w+wgR2R2L17NyyYyZv7b4KRz 9zkHY4213/o2Fq+aVAfnuGTZ79cahp6slOoPOFsooo+cR8V2kdXemyPblnkgwyBL81MdFeru1MWbu KH2svNY8i0NxlHgGA64u9+x+kcXG46UMkhZpEGxVyamhOZidCnvKiEriHmJZBq+4VYdDEkPNwO4H+ bIWDW+2hwlk0NGKLWhmh3ZLo7oJZUq2aZ02/71OwVxvibRMlIyQ6cUf8NBT4rxzPUyWi/dV4eROTD DaFm1gBf1hRhUkxh7jIhBmavkM/t5PDeTTTs7CUMV3GvxqfMiYL16/cYtF5xV6eFytPNewg6QOFNQ fm8MS+UA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t380o-00000009kL1-1M8E; Tue, 22 Oct 2024 06:04:58 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t380l-00000009kKD-1k7F for linux-nvme@lists.infradead.org; Tue, 22 Oct 2024 06:04:56 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id A37FB227AAC; Tue, 22 Oct 2024 08:04:51 +0200 (CEST) Date: Tue, 22 Oct 2024 08:04:51 +0200 From: Christoph Hellwig To: "Martin K. Petersen" Cc: Anuj Gupta , axboe@kernel.dk, hch@lst.de, kbusch@kernel.org, asml.silence@gmail.com, anuj1072538@gmail.com, krisman@suse.de, io-uring@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, gost.dev@samsung.com, linux-scsi@vger.kernel.org, vishak.g@samsung.com, Kanchan Joshi Subject: Re: [PATCH v4 04/11] block: define meta io descriptor Message-ID: <20241022060451.GB10327@lst.de> References: <20241016112912.63542-1-anuj20.g@samsung.com> <20241016112912.63542-5-anuj20.g@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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-20241021_230455_616562_2904B898 X-CRM114-Status: GOOD ( 19.12 ) 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 Mon, Oct 21, 2024 at 10:11:35PM -0400, Martin K. Petersen wrote: > Glad to see the seed added. In NVMe it can be a 64-bit value so we > should bump the size of that field in the user API. > > Not sure what to do about the storage tag. For Linux that would probably > be owned by the filesystem (as opposed to the application). But I guess > one could envision a userland application acting as a storage target and > in that case the tag would need to be passed to the kernel. Right now the series only supports PI on the block device. In that case the userspace application can clearly make use of it. If we want to support PI on file systems (which I'd really like to do for XFS) both ownership models might make sense depending on the file system, although I think just giving it to the application is going to be the only thing we'll see for a while. Maybe we need a way to query if the application can use the app tag?