commit f5113effc2a2ee6b86a4b345ce557353dcbcfffe
author Jan Kara <jack@suse.cz> Tue Jun 04 12:01:45 2013 -0400
committer Theodore Ts'o <tytso@mit.edu> Tue Jun 04 12:01:45 2013 -0400
tree a55e3eb4174ff0d17b9f0523619b9b647774b782
parent 97a851ed71cd9cc2542955e92a001c6ea3d21d35

jbd2: don't create journal_head for temporary journal buffers

When writing metadata to the journal, we create temporary buffer heads
for that task.  We also attach journal heads to these buffer heads but
the only purpose of the journal heads is to keep buffers linked in
transaction's BJ_IO list.  We remove the need for journal heads by
reusing buffer_head's b_assoc_buffers list for that purpose.  Also
since BJ_IO list is just a temporary list for transaction commit, we
use a private list in jbd2_journal_commit_transaction() for that thus
removing BJ_IO list from transaction completely.

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>