From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:46275 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932767AbaCQL6W (ORCPT ); Mon, 17 Mar 2014 07:58:22 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s2HBwLGV007193 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 17 Mar 2014 11:58:21 GMT Received: from userz7021.oracle.com (userz7021.oracle.com [156.151.31.85]) by ucsinet22.oracle.com (8.14.5+Sun/8.14.5) with ESMTP id s2HBwK1U021897 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Mon, 17 Mar 2014 11:58:20 GMT Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by userz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s2HBwKZu022695 for ; Mon, 17 Mar 2014 11:58:20 GMT From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: all super blocks of the replaced disk must be scratched Date: Mon, 17 Mar 2014 19:58:06 +0800 Message-Id: <1395057486-4341-1-git-send-email-Anand.Jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: In a normal scenario when sys-admin replaces a disk, the expeted is btrfs will release the disk completely. However the below test case gives a wrong impression that replaced disk is still is in use. $ btrfs rep start /dev/sde /dev/sdg4 /btrfs $ mkfs.btrfs /dev/sde /dev/sde appears to contain an existing filesystem (btrfs). Error: Use the -f option to force overwrite. --- fs/btrfs/volumes.c | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3c44800..06717a5 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6286,16 +6286,33 @@ int btrfs_scratch_superblock(struct btrfs_device *device) { struct buffer_head *bh; struct btrfs_super_block *disk_super; + int i; + u64 bytenr; - bh = btrfs_read_dev_super(device->bdev); - if (!bh) - return -EINVAL; - disk_super = (struct btrfs_super_block *)bh->b_data; + for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { + bytenr = btrfs_sb_offset(i); + if (bytenr + BTRFS_SUPER_INFO_SIZE >= + i_size_read(device->bdev->bd_inode)) + break; - memset(&disk_super->magic, 0, sizeof(disk_super->magic)); - set_buffer_dirty(bh); - sync_dirty_buffer(bh); - brelse(bh); + bh = __bread(device->bdev, bytenr / 4096, + BTRFS_SUPER_INFO_SIZE); + if (!bh) + continue; + + disk_super = (struct btrfs_super_block *)bh->b_data; + if (btrfs_super_bytenr(disk_super) != bytenr || + btrfs_super_magic(disk_super) != BTRFS_MAGIC) { + brelse(bh); + continue; + } + + memset(&disk_super->magic, 0, sizeof(disk_super->magic)); + + set_buffer_dirty(bh); + sync_dirty_buffer(bh); + brelse(bh); + } return 0; } -- 1.8.5.3