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 40586C02190 for ; Fri, 31 Jan 2025 04:40:30 +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=NIu5WVUHGLf9gfdTWvOvNK/xFsqLPRxW7J/Q8nhUDO0=; b=aqVxv/il9hsHoRr4UL3gxa8vrL M/T6hazmZ8OWJmKPiPnNhjHqv+xmWXtCWE7KcqEfsZnRfXTKTmwx4ukEDPLf2P+t1ilqfTRXRVYUL aYgyIO6PGmcSKM07l8ApFBW0kxBx/ukguuQCqoAnhjTEMb0/qi+MxdL3OnjVZZEQJAY6jPHtd8rk6 Fk7Xke1oskIsQCh224tQvjBIfM4YzXoDnJE811GbHUpkzFlBm+E+gjq6jjYWhx0e6Fi8rLCBbc3JY g/9erbxPGocz00BStX9uwU/vz7eQLzDdqbjjUztvdqhOyYCgq8yNPitbvEqotmTh0O68qN1VvD0WA 9ZqotWXw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tdipN-0000000A06O-2YUX; Fri, 31 Jan 2025 04:40:25 +0000 Received: from outgoing-auth-1.mit.edu ([18.9.28.11] helo=outgoing.mit.edu) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tdipK-0000000A062-1Yyn for linux-nvme@lists.infradead.org; Fri, 31 Jan 2025 04:40:24 +0000 Received: from macsyma.thunk.org ([12.221.73.181]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 50V4eFhe029357 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 30 Jan 2025 23:40:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=outgoing; t=1738298419; bh=NIu5WVUHGLf9gfdTWvOvNK/xFsqLPRxW7J/Q8nhUDO0=; h=Date:From:Subject:Message-ID:MIME-Version:Content-Type; b=PCPw4qxxsROGw2PX/NHKbAd85xP/Eidk7VIu5PmPz2yaHhuHymcZRPeRp1kJsika/ BmqpzMAIc0jLKRf6+bbvE5E3gSl2Oyl8hUwV8oRXF6TdPdRuZc8wqkpOHi4Xd7ZlUE Ke23JkbUo3zBiBMJtO0oWIxFqFoyNZh33Ap7QBgCm4hdFFxMs6pWx00dp/YfquqtT7 EazfVXTezzvo0+RmgElK4dTsjdsBLIEC6oXdnSbMl9i+iXFCVjf4tjCB/Tjhv9jz30 sBGW4sSgoDuRMfKYGvk6yaYyF0rdvp4UNqoP8IIZxgYEyuR7izjO2NZZjZD4jLQh/5 YZieu+n0RShxQ== Received: by macsyma.thunk.org (Postfix, from userid 15806) id 0DD8B344FF0; Thu, 30 Jan 2025 20:40:15 -0800 (PST) Date: Thu, 30 Jan 2025 20:40:15 -0800 From: "Theodore Ts'o" To: "Martin K. Petersen" Cc: Kanchan Joshi , lsf-pc@lists.linux-foundation.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, josef@toxicpanda.com Subject: Re: [Lsf-pc] [LSF/MM/BPF TOPIC] File system checksum offload Message-ID: <20250131044015.GB416991@mit.edu> References: <20250130091545.66573-1-joshi.k@samsung.com> <20250130142857.GB401886@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250130_204022_698420_D143D1CB X-CRM114-Status: GOOD ( 10.44 ) 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 Thu, Jan 30, 2025 at 03:39:20PM -0500, Martin K. Petersen wrote: > It already works that way. If a device advertises being > integrity-capable, the block layer will automatically generate > protection information on write and verify received protection > information on read. Leveraging hardware-accelerated CRC calculation if > the CPU is capable (PCLMULQDQ, etc.). So I'm confused. If that's the case, why do we need Kanchan Joshi's patch to set some magic bio flag and adding a mount option to btrfs? - Ted