Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, ext3 and quota fixes from Jan Kara:
 "Interesting bits are:
   - removal of a special i_mutex locking subclass (I_MUTEX_QUOTA) since
     quota code does not need i_mutex anymore in any unusual way.
   - backport (from ext4) of a fix of a checkpointing bug (missing cache
     flush) that could lead to fs corruption on power failure

  The rest are just random small fixes & cleanups."

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext2: trivial fix to comment for ext2_free_blocks
  ext2: remove the redundant comment for ext2_export_ops
  ext3: return 32/64-bit dir name hash according to usage type
  quota: Get rid of nested I_MUTEX_QUOTA locking subclass
  quota: Use precomputed value of sb_dqopt in dquot_quota_sync
  ext2: Remove i_mutex use from ext2_quota_write()
  reiserfs: Remove i_mutex use from reiserfs_quota_write()
  ext4: Remove i_mutex use from ext4_quota_write()
  ext3: Remove i_mutex use from ext3_quota_write()
  quota: Fix double lock in add_dquot_ref() with CONFIG_QUOTA_DEBUG
  jbd: Write journal superblock with WRITE_FUA after checkpointing
  jbd: protect all log tail updates with j_checkpoint_mutex
  jbd: Split updating of journal superblock and marking journal empty
  ext2: do not register write_super within VFS
  ext2: Remove s_dirt handling
  ext2: write superblock only once on unmount
  ext3: update documentation with barrier=1 default
  ext3: remove max_debt in find_group_orlov()
  jbd: Refine commit writeout logic

1 files changed, 17 insertions, 4 deletions

diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index f2b9a571f4cf..52c15c776029 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -298,6 +298,7 @@ void journal_commit_transaction(journal_t *journal)
 	int tag_flag;
 	int i;
 	struct blk_plug plug;
+	int write_op = WRITE;
 
 	/*
 	 * First job: lock down the current transaction and wait for
@@ -307,7 +308,16 @@ void journal_commit_transaction(journal_t *journal)
 	/* Do we need to erase the effects of a prior journal_flush? */
 	if (journal->j_flags & JFS_FLUSHED) {
 		jbd_debug(3, "super block updated\n");
-		journal_update_superblock(journal, 1);
+		mutex_lock(&journal->j_checkpoint_mutex);
+		/*
+		 * We hold j_checkpoint_mutex so tail cannot change under us.
+		 * We don't need any special data guarantees for writing sb
+		 * since journal is empty and it is ok for write to be
+		 * flushed only with transaction commit.
+		 */
+		journal_update_sb_log_tail(journal, journal->j_tail_sequence,
+					   journal->j_tail, WRITE_SYNC);
+		mutex_unlock(&journal->j_checkpoint_mutex);
 	} else {
 		jbd_debug(3, "superblock not updated\n");
 	}
@@ -413,13 +423,16 @@ void journal_commit_transaction(journal_t *journal)
 
 	jbd_debug (3, "JBD: commit phase 2\n");
 
+	if (tid_geq(journal->j_commit_waited, commit_transaction->t_tid))
+		write_op = WRITE_SYNC;
+
 	/*
 	 * Now start flushing things to disk, in the order they appear
 	 * on the transaction lists.  Data blocks go first.
 	 */
 	blk_start_plug(&plug);
 	err = journal_submit_data_buffers(journal, commit_transaction,
-					  WRITE_SYNC);
+					  write_op);
 	blk_finish_plug(&plug);
 
 	/*
@@ -478,7 +491,7 @@ void journal_commit_transaction(journal_t *journal)
 
 	blk_start_plug(&plug);
 
-	journal_write_revoke_records(journal, commit_transaction, WRITE_SYNC);
+	journal_write_revoke_records(journal, commit_transaction, write_op);
 
 	/*
 	 * If we found any dirty or locked buffers, then we should have
@@ -649,7 +662,7 @@ start_journal_io:
 				clear_buffer_dirty(bh);
 				set_buffer_uptodate(bh);
 				bh->b_end_io = journal_end_buffer_io_sync;
-				submit_bh(WRITE_SYNC, bh);
+				submit_bh(write_op, bh);
 			}
 			cond_resched();