[ Upstream commit 08ba91ee6e2c1c08d3f0648f978cbb5dbf3491d8 ] If NBD_DISCONNECT_ON_CLOSE is set on a device, then the driver will issue a disconnect from nbd_release if the device has no remaining bdev->bd_openers. Fix ret val so reconfigure with only setting the flag succeeds. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>