2008-08-05 01:43:39

by Andrew Morton

[permalink] [raw]
Subject: + jbd-abort-instead-of-waiting-for-nonexistent-transactions.patch added to -mm tree

The patch titled
jbd: abort instead of waiting for nonexistent transactions
has been added to the -mm tree. Its filename is

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See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

Subject: jbd: abort instead of waiting for nonexistent transactions
From: "Duane Griffin" <[email protected]>

The __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:

Signed-off-by: Duane Griffin <[email protected]>
Tested-by: Sami Liedes <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

fs/jbd/checkpoint.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)

diff -puN fs/jbd/checkpoint.c~jbd-abort-instead-of-waiting-for-nonexistent-transactions fs/jbd/checkpoint.c
--- a/fs/jbd/checkpoint.c~jbd-abort-instead-of-waiting-for-nonexistent-transactions
+++ a/fs/jbd/checkpoint.c
@@ -127,14 +127,29 @@ void __log_wait_for_space(journal_t *jou

* 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_list_lock);
nblocks = jbd_space_needed(journal);
if (__log_space_left(journal) < nblocks) {
+ int chkpt = journal->j_checkpoint_transactions != NULL;
+ spin_unlock(&journal->j_list_lock);
- log_do_checkpoint(journal);
+ if (chkpt) {
+ log_do_checkpoint(journal);
+ } else {
+ printk(KERN_ERR "%s: no transactions\n",
+ __func__);
+ journal_abort(journal, 0);
+ }
+ } else {
+ spin_unlock(&journal->j_list_lock);

Patches currently in -mm which might be from [email protected] are