From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759555Ab3HBKJs (ORCPT ); Fri, 2 Aug 2013 06:09:48 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37188 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759444Ab3HBKJp (ORCPT ); Fri, 2 Aug 2013 06:09:45 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miao Xie , Stefan Behrens , Josef Bacik Subject: [ 38/99] Btrfs: fix wrong write offset when replacing a device Date: Fri, 2 Aug 2013 18:07:51 +0800 Message-Id: <20130802100231.389623825@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.4.841.g1a3f60e In-Reply-To: <20130802100225.478715166@linuxfoundation.org> References: <20130802100225.478715166@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefan Behrens commit 115930cb2d444a684975cf2325759cb48ebf80cc upstream. Miao Xie reported the following issue: The filesystem was corrupted after we did a device replace. Steps to reproduce: # mkfs.btrfs -f -m single -d raid10 .. # mount # btrfs replace start -rfB 1 # umount # btrfsck The reason for the issue is that we changed the write offset by mistake, introduced by commit 625f1c8dc. We read the data from the source device at first, and then write the data into the corresponding place of the new device. In order to implement the "-r" option, the source location is remapped using btrfs_map_block(). The read takes place on the mapped location, and the write needs to take place on the unmapped location. Currently the write is using the mapped location, and this commit changes it back by undoing the change to the write address that the aforementioned commit added by mistake. Reported-by: Miao Xie Signed-off-by: Stefan Behrens Signed-off-by: Josef Bacik Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/scrub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -2501,7 +2501,7 @@ again: ret = scrub_extent(sctx, extent_logical, extent_len, extent_physical, extent_dev, flags, generation, extent_mirror_num, - extent_physical); + extent_logical - logical + physical); if (ret) goto out;