dm era: save spacemap metadata root after the pre-commit
authorSomasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Fri, 7 Apr 2017 19:14:55 +0000 (12:14 -0700)
committerMike Snitzer <snitzer@redhat.com>
Mon, 24 Apr 2017 19:02:14 +0000 (15:02 -0400)
commit117aceb030307dcd431fdcff87ce988d3016c34a
tree6ee850484a06b5d14f63617a2a6126cd3f4cac11
parent948f581a53b704b984aa20df009f0a2b4cf7f907
dm era: save spacemap metadata root after the pre-commit

When committing era metadata to disk, it doesn't always save the latest
spacemap metadata root in superblock. Due to this, metadata is getting
corrupted sometimes when reopening the device. The correct order of update
should be, pre-commit (shadows spacemap root), save the spacemap root
(newly shadowed block) to in-core superblock and then the final commit.

Cc: stable@vger.kernel.org
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
drivers/md/dm-era-target.c