From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BACE112CD96 for ; Fri, 31 Jan 2025 04:40:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=18.9.28.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738298442; cv=none; b=jnpmRz4Z0caIKjfkU2Zs1ia45wIOE1y1EAFTwyt966IEvx+4GGQSsxFH582+N9l2yOX+CjEIJ1gdaLvC4JXx3D28Pi1mgrNodHHbvyRu3jUhB6Gj4qTJuH1sKwoO2q4dpR6pFA4rhYRot20diVKiCvuHM+kGmFTqL46UeUc6iOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738298442; c=relaxed/simple; bh=UCGyZjQy6WQrIu39YraJAcmxRCphUxJx3w6t9kNiL8w=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=RAzN2kqYzvnjC7v2L3fGRAf2nNK4PxIY6c+VdWu+GEOaKqrkwIGBPIkL+2C4SvejC3PsZe7nrNbepod2jGdP7qH8XXj751vYrlIBkxMyEWVy3QVkBx6/dkct6goNBBPgYqx5JS2jlbWOULTMiQHfGIkuuzsNhySl80FpQYKmaNk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu; spf=pass smtp.mailfrom=mit.edu; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b=PCPw4qxx; arc=none smtp.client-ip=18.9.28.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b="PCPw4qxx" 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> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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