umem: fix up unplugging

Fix a regression introduced by 7eaceaccab5f40 ("block: remove per-queue
plugging").  In that patch, Jens removed the whole mm_unplug_device()
function, which used to be the trigger to make umem start to work.

We need to implement unplugging to make umem start to work, or I/O will
never be triggered.

Signed-off-by: Tao Guo <[email protected]>
Cc: Neil Brown <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Shaohua Li <[email protected]>
Cc: <[email protected]>
Acked-by: NeilBrown <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions