From: "Austin S. Hemmelgarn" <ahferroin7@xxxxxxxxx> commit 88be159c905a2b4f6d59afa352bef410afb6af02 upstream. Currently, we don't allow the user to try and rebalance to a dup profile on a multi-device filesystem. In most cases, this is a perfectly sensible restriction as raid1 uses the same amount of space and provides better protection. However, when reshaping a multi-device filesystem down to a single device filesystem, this requires the user to convert metadata and system chunks to single profile before deleting devices, and then convert again to dup, which leaves a period of time where metadata integrity is reduced. This patch removes the single-device-only restriction from converting to dup profile to remove this potential data integrity reduction. Signed-off-by: Austin S. Hemmelgarn <ahferroin7@xxxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> --- fs/btrfs/volumes.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index adb5f697a963..89c2aabaea2d 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -3699,10 +3699,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl, num_devices--; } btrfs_dev_replace_unlock(&fs_info->dev_replace); - allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; - if (num_devices == 1) - allowed |= BTRFS_BLOCK_GROUP_DUP; - else if (num_devices > 1) + allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE | BTRFS_BLOCK_GROUP_DUP; + if (num_devices > 1) allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); if (num_devices > 2) allowed |= BTRFS_BLOCK_GROUP_RAID5; -- 2.7.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html