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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46435C636CC for ; Mon, 20 Feb 2023 08:27:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230299AbjBTI1R (ORCPT ); Mon, 20 Feb 2023 03:27:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229810AbjBTI1Q (ORCPT ); Mon, 20 Feb 2023 03:27:16 -0500 Received: from mail-m3164.qiye.163.com (mail-m3164.qiye.163.com [103.74.31.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3133112BC0 for ; Mon, 20 Feb 2023 00:27:14 -0800 (PST) Received: from [192.168.0.234] (unknown [218.94.118.90]) by mail-m3164.qiye.163.com (Hmail) with ESMTPA id 27C0862031E; Mon, 20 Feb 2023 16:27:11 +0800 (CST) Message-ID: Date: Mon, 20 Feb 2023 16:27:10 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [RFC] Live resize of backing device Content-Language: en-US To: Coly Li , Andrea Tomassetti Cc: Eric Wheeler , Kent Overstreet , linux-bcache@vger.kernel.org References: <9474c19e-56f0-cb4d-68c-405c55aef281@ewheeler.net> <4ddb082f-cefc-644e-2ccf-56d41207ecd3@devo.com> <107e8ceb-748e-b296-ae60-c2155d68352d@suse.de> <755CAB25-BC58-4100-A524-6F922E1C13DC@suse.de> <50e64fcd-3bd8-4175-c96e-5fa2ffe051d4@devo.com> <8C5EA413-6FBB-4483-AAFA-2BC0A083C30D@suse.de> From: mingzhe In-Reply-To: <8C5EA413-6FBB-4483-AAFA-2BC0A083C30D@suse.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFJQjdXWS1ZQUlXWQ8JGhUIEh9ZQVkaT0sZVh5LH05LHk9ITktLQ1UZERMWGhIXJBQOD1 lXWRgSC1lBWUlKQ1VCT1VKSkNVQktZV1kWGg8SFR0UWUFZT0tIVUpKS0hKTFVKS0tVS1kG X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6Ojo6Sww6TjJJSEkxFQkQEEkp AQswCS1VSlVKTUxNQ0NKTUhKTExOVTMWGhIXVRYSFRwBEx5VARQOOx4aCAIIDxoYEFUYFUVZV1kS C1lBWUlKQ1VCT1VKSkNVQktZV1kIAVlBTklPQjcG X-HM-Tid: 0a866def185600a4kurm27c0862031e Precedence: bulk List-ID: X-Mailing-List: linux-bcache@vger.kernel.org 在 2023/2/19 17:39, Coly Li 写道: > > >> 2023年1月27日 20:44，Andrea Tomassetti 写道： >> >> From 83f490ec8e81c840bdaf69e66021d661751975f2 Mon Sep 17 00:00:00 2001 >> From: Andrea Tomassetti >> Date: Thu, 8 Sep 2022 09:47:55 +0200 >> Subject: [PATCH v2] bcache: Add support for live resize of backing devices >> >> Signed-off-by: Andrea Tomassetti > > Hi Andrea, > > I am fine with this patch and added it in my test queue now. Do you have an updated version, (e.g. more coding refine or adding commit log), then I can update my local version. > > BTW, it could be better if the patch will be sent out as a separated email. > > Thanks. > > Coly Li > Hi, Coly I posted some patchsets about online resize. -[PATCH v5 1/3] bcache: add dirty_data in struct bcache_device -[PATCH v5 2/3] bcache: allocate stripe memory when partial_stripes_expensive is true -[PATCH v5 3/3] bcache: support online resizing of cached_dev There are some differences: 1. Create /sys/block/bcache0/bcache/size in sysfs to trigger resize 2. Allocate stripe memory only if partial_stripes_expensive is true 3. Simplify bcache_dev_sectors_dirty() Since the bcache superblock uses some sectors, the actual space of the bcache device is smaller than the backing. In order to provide a bcache device with a user-specified size, we need to create a backing device with a larger space, and then resize bcache. So resize can specify the size is very necessary. > > >> --- >> Hi Coly, >> this is the second version of the patch. As you correctly pointed out, >> I implemented roll-back functionalities in case of error. >> I'm testing this funcionality using QEMU/KVM vm via libvirt. >> Here the steps: >> 1. make-bcache --writeback -B /dev/vdb -C /dev/vdc >> 2. mkfs.xfs /dev/bcache0 >> 3. mount /dev/bcache0 /mnt >> 3. dd if=/dev/random of=/mnt/random0 bs=1M count=1000 >> 4. md5sum /mnt/random0 | tee /mnt/random0.md5 >> 5. [HOST] virsh blockresize --path --size >> 6. xfs_growfs /dev/bcache0 >> 6. Repeat steps 3 and 4 with a different file name (e.g. random1.md5) >> 7. umount/reboot/remount and check that the md5 hashes are correct with >> md5sum -c /mnt/random?.md5 >> >> drivers/md/bcache/super.c | 84 ++++++++++++++++++++++++++++++++++++++- >> 1 file changed, 83 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c >> index ba3909bb6bea..1435a3f605f8 100644 >> --- a/drivers/md/bcache/super.c >> +++ b/drivers/md/bcache/super.c >>> > > [snipped] > >