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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5AFE2C8300C for ; Tue, 27 Oct 2020 00:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A3062080A for ; Tue, 27 Oct 2020 00:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603759571; bh=ZQ4rUae0MFq+q+xuLJba7D1u85eRkZ30SW3jH8xmVcU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=csroA1kqf+yttfMpxlAN24oqpyWScejAlYV1P3/lF1b074hVusCbaHe63aM+QxgxN 6tOB9nbxxUyWiYmRADcybh2cnsN3f5WEFd3E0Dz59cgRMP4VX1zexAMNG2TIlSQS60 DQpcrfBXuBW7eS8tW3gwT/2pGFWwYirBPx14s/VQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408716AbgJ0AmY (ORCPT ); Mon, 26 Oct 2020 20:42:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:51610 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2409336AbgJZXvM (ORCPT ); Mon, 26 Oct 2020 19:51:12 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D53E62075B; Mon, 26 Oct 2020 23:51:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603756272; bh=ZQ4rUae0MFq+q+xuLJba7D1u85eRkZ30SW3jH8xmVcU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W046cHoSC3Ov5I62XBdCKcxid8qUDspHjLObY70QsaiHQIz5fwFr5JNuPahqqXzx8 SwjQFyY4vFxYU/eoVxZvhBUAtG88pLNX0LpNsBG9XQY0QwW92Gqfwo4BqczYD23b0R PVSXppiq24XeIan7lLqYMBL5XkUVX3GBZxiA0F7U= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Anand Jain , David Sterba , Sasha Levin , linux-btrfs@vger.kernel.org Subject: [PATCH AUTOSEL 5.9 104/147] btrfs: fix replace of seed device Date: Mon, 26 Oct 2020 19:48:22 -0400 Message-Id: <20201026234905.1022767-104-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201026234905.1022767-1-sashal@kernel.org> References: <20201026234905.1022767-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Anand Jain [ Upstream commit c6a5d954950c5031444173ad2195efc163afcac9 ] If you replace a seed device in a sprouted fs, it appears to have successfully replaced the seed device, but if you look closely, it didn't. Here is an example. $ mkfs.btrfs /dev/sda $ btrfstune -S1 /dev/sda $ mount /dev/sda /btrfs $ btrfs device add /dev/sdb /btrfs $ umount /btrfs $ btrfs device scan --forget $ mount -o device=/dev/sda /dev/sdb /btrfs $ btrfs replace start -f /dev/sda /dev/sdc /btrfs $ echo $? 0 BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc started BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc finished $ btrfs fi show Label: none uuid: ab2c88b7-be81-4a7e-9849-c3666e7f9f4f Total devices 2 FS bytes used 256.00KiB devid 1 size 3.00GiB used 520.00MiB path /dev/sdc devid 2 size 3.00GiB used 896.00MiB path /dev/sdb Label: none uuid: 10bd3202-0415-43af-96a8-d5409f310a7e Total devices 1 FS bytes used 128.00KiB devid 1 size 3.00GiB used 536.00MiB path /dev/sda So as per the replace start command and kernel log replace was successful. Now let's try to clean mount. $ umount /btrfs $ btrfs device scan --forget $ mount -o device=/dev/sdc /dev/sdb /btrfs mount: /btrfs: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error. [ 636.157517] BTRFS error (device sdc): failed to read chunk tree: -2 [ 636.180177] BTRFS error (device sdc): open_ctree failed That's because per dev items it is still looking for the original seed device. $ btrfs inspect-internal dump-tree -d /dev/sdb item 0 key (DEV_ITEMS DEV_ITEM 1) itemoff 16185 itemsize 98 devid 1 total_bytes 3221225472 bytes_used 545259520 io_align 4096 io_width 4096 sector_size 4096 type 0 generation 6 start_offset 0 dev_group 0 seek_speed 0 bandwidth 0 uuid 59368f50-9af2-4b17-91da-8a783cc418d4 <--- seed uuid fsid 10bd3202-0415-43af-96a8-d5409f310a7e <--- seed fsid item 1 key (DEV_ITEMS DEV_ITEM 2) itemoff 16087 itemsize 98 devid 2 total_bytes 3221225472 bytes_used 939524096 io_align 4096 io_width 4096 sector_size 4096 type 0 generation 0 start_offset 0 dev_group 0 seek_speed 0 bandwidth 0 uuid 56a0a6bc-4630-4998-8daf-3c3030c4256a <- sprout uuid fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f <- sprout fsid But the replaced target has the following uuid+fsid in its superblock which doesn't match with the expected uuid+fsid in its devitem. $ btrfs in dump-super /dev/sdc | egrep '^generation|dev_item.uuid|dev_item.fsid|devid' generation 20 dev_item.uuid 59368f50-9af2-4b17-91da-8a783cc418d4 dev_item.fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f [match] dev_item.devid 1 So if you provide the original seed device the mount shall be successful. Which so long happening in the test case btrfs/163. $ btrfs device scan --forget $ mount -o device=/dev/sda /dev/sdb /btrfs Fix in this patch: If a seed is not sprouted then there is no replacement of it, because of its read-only filesystem with a read-only device. Similarly, in the case of a sprouted filesystem, the seed device is still read only. So, mark it as you can't replace a seed device, you can only add a new device and then delete the seed device. If replace is attempted then returns -EINVAL. Signed-off-by: Anand Jain Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/dev-replace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c index e4a1c6afe35dc..0cb36746060da 100644 --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -230,7 +230,7 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, int ret = 0; *device_out = NULL; - if (fs_info->fs_devices->seeding) { + if (srcdev->fs_devices->seeding) { btrfs_err(fs_info, "the filesystem is a seed filesystem!"); return -EINVAL; } -- 2.25.1