From 23f8b79eae8a74e42a006ffa7c456e295c7e1c0d Mon Sep 17 00:00:00 2001 From: Duane Griffin Date: Wed, 8 Oct 2008 23:28:31 -0400 Subject: jbd2: abort instead of waiting for nonexistent transaction The __jbd2_log_wait_for_space function sits in a loop checkpointing transactions until there is sufficient space free in the journal. However, if there are no transactions to be processed (e.g. because the free space calculation is wrong due to a corrupted filesystem) it will never progress. Check for space being required when no transactions are outstanding and abort the journal instead of endlessly looping. This patch fixes the bug reported by Sami Liedes at: http://bugzilla.kernel.org/show_bug.cgi?id=10976 Signed-off-by: Duane Griffin Cc: Sami Liedes Cc: Signed-off-by: Andrew Morton Signed-off-by: "Theodore Ts'o" --- fs/jbd2/checkpoint.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'fs/jbd2') diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index 91389c8aee8a..af4651bf3570 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -126,14 +126,29 @@ void __jbd2_log_wait_for_space(journal_t *journal) /* * Test again, another process may have checkpointed while we - * were waiting for the checkpoint lock + * were waiting for the checkpoint lock. If there are no + * outstanding transactions there is nothing to checkpoint and + * we can't make progress. Abort the journal in this case. */ spin_lock(&journal->j_state_lock); + spin_lock(&journal->j_list_lock); nblocks = jbd_space_needed(journal); if (__jbd2_log_space_left(journal) < nblocks) { + int chkpt = journal->j_checkpoint_transactions != NULL; + + spin_unlock(&journal->j_list_lock); spin_unlock(&journal->j_state_lock); - jbd2_log_do_checkpoint(journal); + if (chkpt) { + jbd2_log_do_checkpoint(journal); + } else { + printk(KERN_ERR "%s: no transactions\n", + __func__); + jbd2_journal_abort(journal, 0); + } + spin_lock(&journal->j_state_lock); + } else { + spin_unlock(&journal->j_list_lock); } mutex_unlock(&journal->j_checkpoint_mutex); } -- cgit v1.2.3