[PATCH 7/9] rbd: drop dev registration check for new snap

[Alex Elder <elder@inktank.com>]

By the time rbd_dev_snaps_register() gets called during rbd device
initialization, the main device will have already been registered.
Similarly, a header refresh will only occur for an rbd device whose
Linux device is registered.  There is therefore no need to verify
the main device is registered when registering a snapshot device.

For the time being, turn the check into a WARN_ON(), but it can
eventually just go away.

Signed-off-by: Alex Elder <elder@inktank.com>
---
 drivers/block/rbd.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 8e82610..e6af38f 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -2253,8 +2253,8 @@ static int rbd_dev_snaps_register(struct
rbd_device *rbd_dev)
 	int ret = 0;

 	dout("%s called\n", __func__);
-	if (!device_is_registered(&rbd_dev->dev))
-		return 0;
+	if (WARN_ON(!device_is_registered(&rbd_dev->dev)))
+		return -EIO;

 	list_for_each_entry(snap, &rbd_dev->snaps, node) {
 		if (!rbd_snap_registered(snap)) {
-- 
1.7.9.5