fix nspace assignment in LFNIndex::lfn_parse_object_name

The unused ns variable is assigned to the nspace data member of the
parsed hobject_t. It would be nicer to use a constructor accepting
the namespace in argument.

http://tracker.ceph.com/issues/4597 refs #4597

Signed-off-by: Loic Dachary <loic@dachary.org>
Merge pull request #176 from dachary/wip-4597

fix nspace assignment in LFNIndex::lfn_parse_object_name

Reviewed-by: Samuel Just <sam.just@inktank.com>
FileJournal: fill in committed_up_to for old headers

Signed-off-by: Samuel Just <sam.just@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
FileJournal: introduce start_seq header entry

FileStore::header_t::start_seq now encodes the op seq which may be
written at FileStore::header_t::start.  This way, FileStore::open()
can pass a valid sequence number to read_entry for validation.
Otherwise, read_entry has no way of knowing whether a failure of a
read at header.start indicates that the journal was empty, or that
the entry is corrupt.  With start_seq, read_entry can assume
corruption if start_seq <= committed_up_to.

Fixes: #4527
Signed-off-by: Samuel Just <sam.just@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Merge git://github.com/ceph/ceph