From dabb44334060b4b84051b34c58573e57cc7432b2 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kmo@daterainc.com>
Date: Wed, 19 Feb 2014 19:48:26 -0800
Subject: [PATCH] bcache: Fix a shutdown bug

Shutdown wasn't cancelling/waiting on journal_write_work()

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
---
 drivers/md/bcache/journal.c | 9 +++++++--
 drivers/md/bcache/journal.h | 1 +
 drivers/md/bcache/super.c   | 4 ++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 18039affc306..e38c5997bf12 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -536,6 +536,7 @@ void bch_journal_next(struct journal *j)
 	atomic_set(&fifo_back(&j->pin), 1);
 
 	j->cur->data->seq	= ++j->seq;
+	j->cur->dirty		= false;
 	j->cur->need_write	= false;
 	j->cur->data->keys	= 0;
 
@@ -731,7 +732,10 @@ static void journal_write_work(struct work_struct *work)
 					   struct cache_set,
 					   journal.work);
 	spin_lock(&c->journal.lock);
-	journal_try_write(c);
+	if (c->journal.cur->dirty)
+		journal_try_write(c);
+	else
+		spin_unlock(&c->journal.lock);
 }
 
 /*
@@ -761,7 +765,8 @@ atomic_t *bch_journal(struct cache_set *c,
 	if (parent) {
 		closure_wait(&w->wait, parent);
 		journal_try_write(c);
-	} else if (!w->need_write) {
+	} else if (!w->dirty) {
+		w->dirty = true;
 		schedule_delayed_work(&c->journal.work,
 				      msecs_to_jiffies(c->journal_delay_ms));
 		spin_unlock(&c->journal.lock);
diff --git a/drivers/md/bcache/journal.h b/drivers/md/bcache/journal.h
index 9180c4465075..e3c39457afbb 100644
--- a/drivers/md/bcache/journal.h
+++ b/drivers/md/bcache/journal.h
@@ -95,6 +95,7 @@ struct journal_write {
 
 	struct cache_set	*c;
 	struct closure_waitlist	wait;
+	bool			dirty;
 	bool			need_write;
 };
 
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 24a3a1546caa..c70521fe57a6 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1403,6 +1403,10 @@ static void cache_set_flush(struct closure *cl)
 		if (ca->alloc_thread)
 			kthread_stop(ca->alloc_thread);
 
+	cancel_delayed_work_sync(&c->journal.work);
+	/* flush last journal entry if needed */
+	c->journal.work.work.func(&c->journal.work.work);
+
 	closure_return(cl);
 }