diff options
| author | Eric Sandeen <sandeen@redhat.com> | 2012-08-18 22:29:40 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-13 05:50:21 +0900 |
| commit | 14b4ed22a6b5fc1549504336131be4f5f6ba1bf4 (patch) | |
| tree | 11d36afec15a80b1478429e8511c55d4455946c7 /fs | |
| parent | d024fea7032bc7c333c967db530b44d59a180d14 (diff) | |
jbd2: don't write superblock when if its empty
commit eeecef0af5ea4efd763c9554cf2bd80fc4a0efd3 upstream.
This sequence:
# truncate --size=1g fsfile
# mkfs.ext4 -F fsfile
# mount -o loop,ro fsfile /mnt
# umount /mnt
# dmesg | tail
results in an IO error when unmounting the RO filesystem:
[ 318.020828] Buffer I/O error on device loop1, logical block 196608
[ 318.027024] lost page write due to I/O error on loop1
[ 318.032088] JBD2: Error -5 detected when updating journal superblock for loop1-8.
This was a regression introduced by commit 24bcc89c7e7c: "jbd2: split
updating of journal superblock and marking journal empty".
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/jbd2/journal.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index e149b99a7ffb..484b8d1c6cb6 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1354,6 +1354,11 @@ static void jbd2_mark_journal_empty(journal_t *journal) BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); read_lock(&journal->j_state_lock); + /* Is it already empty? */ + if (sb->s_start == 0) { + read_unlock(&journal->j_state_lock); + return; + } jbd_debug(1, "JBD2: Marking journal as empty (seq %d)\n", journal->j_tail_sequence); |