Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

Pull MD updates from Shaohua Li:
 "Some small fixes for MD:

   - fix raid5-cache potential problems if raid5 cache isn't fully
     recovered

   - fix a wait-within-wait warning in raid1/10

   - make raid5-PPL support disks with writeback cache enabled"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  raid5-ppl: PPL support for disks with write-back cache enabled
  md/r5cache: print more info of log recovery
  md/raid1,raid10: silence warning about wait-within-wait
  md: introduce new personality funciton start()

1 files changed, 23 insertions, 8 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index cb1476214f3f..0081ace39a64 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -711,7 +711,7 @@ static struct md_rdev *find_rdev(struct mddev *mddev, dev_t dev)
 	return NULL;
 }
 
-static struct md_rdev *find_rdev_rcu(struct mddev *mddev, dev_t dev)
+struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev)
 {
 	struct md_rdev *rdev;
 
@@ -721,6 +721,7 @@ static struct md_rdev *find_rdev_rcu(struct mddev *mddev, dev_t dev)
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(md_find_rdev_rcu);
 
 static struct md_personality *find_pers(int level, char *clevel)
 {
@@ -5560,11 +5561,6 @@ int md_run(struct mddev *mddev)
 	if (start_readonly && mddev->ro == 0)
 		mddev->ro = 2; /* read-only, but switch on first write */
 
-	/*
-	 * NOTE: some pers->run(), for example r5l_recovery_log(), wakes
-	 * up mddev->thread. It is important to initialize critical
-	 * resources for mddev->thread BEFORE calling pers->run().
-	 */
 	err = pers->run(mddev);
 	if (err)
 		pr_warn("md: pers->run() failed ...\n");
@@ -5678,6 +5674,9 @@ static int do_md_run(struct mddev *mddev)
 	if (mddev_is_clustered(mddev))
 		md_allow_write(mddev);
 
+	/* run start up tasks that require md_thread */
+	md_start(mddev);
+
 	md_wakeup_thread(mddev->thread);
 	md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 
@@ -5689,6 +5688,21 @@ out:
 	return err;
 }
 
+int md_start(struct mddev *mddev)
+{
+	int ret = 0;
+
+	if (mddev->pers->start) {
+		set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
+		md_wakeup_thread(mddev->thread);
+		ret = mddev->pers->start(mddev);
+		clear_bit(MD_RECOVERY_WAIT, &mddev->recovery);
+		md_wakeup_thread(mddev->sync_thread);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(md_start);
+
 static int restart_array(struct mddev *mddev)
 {
 	struct gendisk *disk = mddev->gendisk;
@@ -6997,7 +7011,7 @@ static int set_disk_faulty(struct mddev *mddev, dev_t dev)
 		return -ENODEV;
 
 	rcu_read_lock();
-	rdev = find_rdev_rcu(mddev, dev);
+	rdev = md_find_rdev_rcu(mddev, dev);
 	if (!rdev)
 		err =  -ENODEV;
 	else {
@@ -8169,7 +8183,8 @@ void md_do_sync(struct md_thread *thread)
 	int ret;
 
 	/* just incase thread restarts... */
-	if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
+	if (test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
+	    test_bit(MD_RECOVERY_WAIT, &mddev->recovery))
 		return;
 	if (mddev->ro) {/* never try to sync a read-only array */
 		set_bit(MD_RECOVERY_INTR, &mddev->recovery);