[22/90] ext4: Use bforget() in no journal mode for ext4_journal_{forget,revoke}()

Greg KH
2009-12-11T04:36:48Z

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2.6.31-stable review patch. If anyone has any objections, please let us know.

------------------
(cherry picked from commit c7acb4c16646943180bd221c167a077e0a084f9c)

When ext4 is using a journal, a metadata block which is deallocated
must be passed into the journal layer so it can be dropped from the
current transaction and/or revoked. This is done by calling the
functions ext4_journal_forget() and ext4_journal_revoke(), which call
jbd2_journal_forget(), and jbd2_journal_revoke(), respectively.

Since the jbd2_journal_forget() and jbd2_journal_revoke() call
bforget(), if ext4 is not using a journal, ext4_journal_forget() and
ext4_journal_revoke() must call bforget() to avoid a dirty metadata
block overwriting a block after it has been reallocated and reused for
another inode's data block.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
fs/ext4/ext4_jbd2.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -44,7 +44,7 @@ int __ext4_journal_forget(const char *wh
handle, err);
}
else
- brelse(bh);
+ bforget(bh);
return err;
}

@@ -60,7 +60,7 @@ int __ext4_journal_revoke(const char *wh
handle, err);
}
else
- brelse(bh);
+ bforget(bh);
return err;
}