cleanup updating the size of block devices

[Christoph Hellwig]

Hi Jens,

this series builds on top of the work that went into the last merge window,
and make sure we have a single coherent interfac for updating the size of a
block device.

Diffstat:
 block/genhd.c                  |   16 +++----
 drivers/block/aoe/aoecmd.c     |   15 +-----
 drivers/block/drbd/drbd_main.c |    6 --
 drivers/block/loop.c           |   36 ++--------------
 drivers/block/nbd.c            |   88 +++++++++++++----------------------------
 drivers/block/pktcdvd.c        |    3 -
 drivers/block/rbd.c            |    3 -
 drivers/block/rnbd/rnbd-clt.c  |    3 -
 drivers/block/virtio_blk.c     |    3 -
 drivers/block/xen-blkfront.c   |    2 
 drivers/block/zram/zram_drv.c  |    7 ---
 drivers/md/dm-raid.c           |    3 -
 drivers/md/dm.c                |    3 -
 drivers/md/md-cluster.c        |    8 ---
 drivers/md/md-linear.c         |    3 -
 drivers/md/md.c                |   24 ++++-------
 drivers/nvme/host/core.c       |   18 --------
 drivers/scsi/sd.c              |    9 +---
 fs/block_dev.c                 |    7 ---
 include/linux/genhd.h          |    3 -
 20 files changed, 76 insertions(+), 184 deletions(-)