From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A55C8B660; Fri, 11 Jul 2025 08:46:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752223604; cv=none; b=c2CcuDvq8OLmnhi4Wr0HN2B0LfkoRsf7I2qI6ncpO0ukKd9LQv5fI3yoAoGpqIRWAKz0Pczch+r1SV52W8xVG96aZtYWFpKxXBXIOjTsNXUS5sS360rwSUMUwG/zaDBsEmDVRYfnjsMamx+Jgskgw8gyTKEHJ006+3n+JbzsNrs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752223604; c=relaxed/simple; bh=zz+PKe2EsN0dWLcgsiYIFzIKc+Zya4xi9vnyYf/TK/w=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=FiTGSbWUixOh0M8tRaNQ67pQKTj/DLHon08KIOqDQCHrsNv3p9gLjKqLm4F/wHrJy/FicBtygMdd35Wcdm1Ni3hCie4wnNqtiHmO81453mwAY5RT8N8N+MITcqik9WTwqTymZOIC5F3Z8peBKD4Ho3xjogR5pDxzDrdEhimYufY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=troOG8RC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="troOG8RC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CADA2C4CEED; Fri, 11 Jul 2025 08:46:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752223604; bh=zz+PKe2EsN0dWLcgsiYIFzIKc+Zya4xi9vnyYf/TK/w=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=troOG8RClEjyGE8ygTNPlfsvcY+w+84KlZr+jaTgh/8x2kjC6+qlnol2gTDtGQdaL qfr1mxxDPNkaRRrKy24Ynpx+ZNL329fgILm6pgNFTIDOnZvBiXef+oqW2XWCthZsYi 7zk80MrmKItxlxsMSbxPkBkUW9iUBFEqnHmVEDH7zjVhyEkF3Vkrv0mdM2u2AmJLiZ NEa5FME1qmKsF3nbC8iw+ZHmoqtJVStTKYUjVxfuJ9bmF9SUezddmEkC37nkO7SxSX JzDrliniDmL0lADcXEQ4VDylcCmQmQ3OqM7c0N1scPV66droDmBAbPAPef/F7jMtAs r6vq6CBycSGmQ== Message-ID: Date: Fri, 11 Jul 2025 17:44:26 +0900 Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 0/6] block/md/dm: set chunk_sectors from stacked dev stripe size To: John Garry , agk@redhat.com, snitzer@kernel.org, mpatocka@redhat.com, song@kernel.org, yukuai3@huawei.com, hch@lst.de, nilay@linux.ibm.com, axboe@kernel.dk, cem@kernel.org Cc: dm-devel@lists.linux.dev, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, linux-block@vger.kernel.org, ojaswin@linux.ibm.com, martin.petersen@oracle.com, akpm@linux-foundation.org, linux-xfs@vger.kernel.org, djwong@kernel.org References: <20250711080929.3091196-1-john.g.garry@oracle.com> From: Damien Le Moal Content-Language: en-US Organization: Western Digital Research In-Reply-To: <20250711080929.3091196-1-john.g.garry@oracle.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/11/25 5:09 PM, John Garry wrote: > This value in io_min is used to configure any atomic write limit for the > stacked device. The idea is that the atomic write unit max is a > power-of-2 factor of the stripe size, and the stripe size is available > in io_min. > > Using io_min causes issues, as: > a. it may be mutated > b. the check for io_min being set for determining if we are dealing with > a striped device is hard to get right, as reported in [0]. > > This series now sets chunk_sectors limit to share stripe size. Hmm... chunk_sectors for a zoned device is the zone size. So is this all safe if we are dealing with a zoned block device that also supports atomic writes ? Not that I know of any such device, but better be safe, so maybe for now do not enable atomic write support on zoned devices ? -- Damien Le Moal Western Digital Research