Pull block layer driver update from Jens Axboe:
 "This is the block driver pull request for 3.18.  Not a lot in there
  this round, and nothing earth shattering.

   - A round of drbd fixes from the linbit team, and an improvement in
     asender performance.

   - Removal of deprecated (and unused) IRQF_DISABLED flag in rsxx and
     hd from Michael Opdenacker.

   - Disable entropy collection from flash devices by default, from Mike
     Snitzer.

   - A small collection of xen blkfront/back fixes from Roger Pau Monné
     and Vitaly Kuznetsov"

* 'for-3.18/drivers' of git://git.kernel.dk/linux-block:
  block: disable entropy contributions for nonrot devices
  xen, blkfront: factor out flush-related checks from do_blkif_request()
  xen-blkback: fix leak on grant map error path
  xen/blkback: unmap all persistent grants when frontend gets disconnected
  rsxx: Remove deprecated IRQF_DISABLED
  block: hd: remove deprecated IRQF_DISABLED
  drbd: use RB_DECLARE_CALLBACKS() to define augment callbacks
  drbd: compute the end before rb_insert_augmented()
  drbd: Add missing newline in resync progress display in /proc/drbd
  drbd: reduce lock contention in drbd_worker
  drbd: Improve asender performance
  drbd: Get rid of the WORK_PENDING macro
  drbd: Get rid of the __no_warn and __cond_lock macros
  drbd: Avoid inconsistent locking warning
  drbd: Remove superfluous newline from "resync_extents" debugfs entry.
  drbd: Use consistent names for all the bi_end_io callbacks
  drbd: Use better variable names