md: split detach operation out from ->stop.

Each md personality has a 'stop' operation which does two
things:
 1/ it finalizes some aspects of the array to ensure nothing
    is accessing the ->private data
 2/ it frees the ->private data.

All the steps in '1' can apply to all arrays and so can be
performed in common code.

This is useful as in the case where we change the personality which
manages an array (in level_store()), it would be helpful to do
step 1 early, and step 2 later.

So split the 'step 1' functionality out into a new mddev_detach().

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 0 insertions, 2 deletions

diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index fedb1b31877d..9fe34453835b 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -504,8 +504,6 @@ static int multipath_stop (struct mddev *mddev)
 {
 	struct mpconf *conf = mddev->private;
 
-	md_unregister_thread(&mddev->thread);
-	blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
 	mempool_destroy(conf->pool);
 	kfree(conf->multipaths);
 	kfree(conf);