On Tue, Jun 18, 2019 at 07:42:46AM +0000, Naohiro Aota wrote: > On 2019/06/13 23:09, Josef Bacik wrote: > > On Fri, Jun 07, 2019 at 10:10:14PM +0900, Naohiro Aota wrote: > >> If the btrfs volume has mirrored block groups, it unconditionally makes > >> un-mirrored block groups read only. When we have mirrored block groups, but > >> don't have writable block groups, this will drop all writable block groups. > >> So, check if we have at least one writable mirrored block group before > >> setting un-mirrored block groups read only. > >> > > > > I don't understand why you want this. Thanks, > > > > Josef > > > > This is necessary to handle e.g. btrfs/124 case. > > When we mount degraded RAID1 FS and write to it, and then > re-mount with full device, the write pointers of corresponding > zones of written BG differ. The patch 07 mark such block group > as "wp_broken" and make it read only. In this situation, we only > have read only RAID1 BGs because of "wp_broken" and un-mirrored BGs > are also marked read only, because we have RAID1 BGs. > As a result, all the BGs are now read only, so that we > cannot even start the rebalance to fix the situation. Ah ok, please add this explanation to the changelog. Thanks, Josef
