[Patch] JBD and JBD2 missing set_freezable()

[Nigel Cunningham <nigel@tuxonice.net>]

Hi all.

With the latest and greatest changes to the freezer, I started seeing
panics that were caused by jbd2 running post-process freezing and
hitting the canary BUG_ON for non-TuxOnIce I/O submission. I've traced
this back to a lack of set_freezable calls in both jbd and jbd2. Since
they're clearly meant to be frozen (there are tests for freezing()), I
submit the following patch to add the missing calls.

Signed-off-by: Nigel Cunningham <nigel@tuxonice.net>

diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
index 59c09f9..89cd985 100644
--- a/fs/jbd/journal.c
+++ b/fs/jbd/journal.c
@@ -129,6 +129,8 @@ static int kjournald(void *arg)
 	setup_timer(&journal->j_commit_timer, commit_timeout,
 			(unsigned long)current);

+	set_freezable();
+
 	/* Record that the journal thread is running */
 	journal->j_task = current;
 	wake_up(&journal->j_wait_done_commit);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index c0a5f9f..663e47c 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -139,6 +139,8 @@ static int kjournald2(void *arg)
 	setup_timer(&journal->j_commit_timer, commit_timeout,
 			(unsigned long)current);

+	set_freezable();
+
 	/* Record that the journal thread is running */
 	journal->j_task = current;
 	wake_up(&journal->j_wait_done_commit);
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