diff options
| author | Jan Kara <jack@suse.cz> | 2012-04-07 12:50:13 +0200 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2012-05-15 23:34:36 +0200 |
| commit | 1ce8486dcc00c1e095af8d155fa4451936b89013 (patch) | |
| tree | 416fc385dc25993f0a968d1a78fb07dd0b79be34 /fs/jbd/journal.c | |
| parent | 9754e39c7bc51328f145e933bfb0df47cd67b6e9 (diff) | |
jbd: protect all log tail updates with j_checkpoint_mutex
There are some log tail updates that are not protected by j_checkpoint_mutex.
Some of these are harmless because they happen during startup or shutdown but
updates in journal_commit_transaction() and journal_flush() can really race
with other log tail updates (e.g. someone doing journal_flush() with someone
running cleanup_journal_tail()). So protect all log tail updates with
j_checkpoint_mutex.
Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'fs/jbd/journal.c')
| -rw-r--r-- | fs/jbd/journal.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c index 44c104abfb36..b29c7678525d 100644 --- a/fs/jbd/journal.c +++ b/fs/jbd/journal.c @@ -936,8 +936,11 @@ static int journal_reset(journal_t *journal) journal->j_errno); journal->j_flags |= JFS_FLUSHED; } else { + /* Lock here to make assertions happy... */ + mutex_lock(&journal->j_checkpoint_mutex); /* Add the dynamic fields and write it to disk. */ journal_update_sb_log_tail(journal); + mutex_unlock(&journal->j_checkpoint_mutex); } return journal_start_thread(journal); } @@ -1061,6 +1064,7 @@ void journal_update_sb_log_tail(journal_t *journal) { journal_superblock_t *sb = journal->j_superblock; + BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); spin_lock(&journal->j_state_lock); jbd_debug(1,"JBD: updating superblock (start %u, seq %d, errno %d)\n", journal->j_tail, journal->j_tail_sequence, journal->j_errno); @@ -1089,6 +1093,7 @@ static void mark_journal_empty(journal_t *journal) { journal_superblock_t *sb = journal->j_superblock; + BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); spin_lock(&journal->j_state_lock); jbd_debug(1, "JBD: Marking journal as empty (seq %d)\n", journal->j_tail_sequence); @@ -1293,6 +1298,8 @@ int journal_destroy(journal_t *journal) /* Force any old transactions to disk */ + /* We cannot race with anybody but must keep assertions happy */ + mutex_lock(&journal->j_checkpoint_mutex); /* Totally anal locking here... */ spin_lock(&journal->j_list_lock); while (journal->j_checkpoint_transactions != NULL) { @@ -1315,6 +1322,7 @@ int journal_destroy(journal_t *journal) err = -EIO; brelse(journal->j_sb_buffer); } + mutex_unlock(&journal->j_checkpoint_mutex); if (journal->j_inode) iput(journal->j_inode); @@ -1528,6 +1536,7 @@ int journal_flush(journal_t *journal) if (is_journal_aborted(journal)) return -EIO; + mutex_lock(&journal->j_checkpoint_mutex); cleanup_journal_tail(journal); /* Finally, mark the journal as really needing no recovery. @@ -1536,6 +1545,7 @@ int journal_flush(journal_t *journal) * commits of data to the journal will restore the current * s_start value. */ mark_journal_empty(journal); + mutex_unlock(&journal->j_checkpoint_mutex); spin_lock(&journal->j_state_lock); J_ASSERT(!journal->j_running_transaction); J_ASSERT(!journal->j_committing_transaction); @@ -1576,8 +1586,12 @@ int journal_wipe(journal_t *journal, int write) write ? "Clearing" : "Ignoring"); err = journal_skip_recovery(journal); - if (write) + if (write) { + /* Lock to make assertions happy... */ + mutex_lock(&journal->j_checkpoint_mutex); mark_journal_empty(journal); + mutex_unlock(&journal->j_checkpoint_mutex); + } no_recovery: return err; |