[GIT PULL] xen blkfront barrier updates

[Jeremy Fitzhardinge <jeremy@goop.org>]

Hi Jens,

Here's the xen-blkfront barrier changes we discussed in Boston (its
identical to the last posted version).

The only comment was Christoph pointing out EOPNOTSUPP is not used in
the block interface, but blkfront is just using it as a local
placeholder and it never gets returned up to the block layer.

I still haven't sorted out what's going on with the backends; we
definitely need either a FLUSH operation or make empty WRITE_BARRIER
work to flush disk caches.

Thanks,
    J

The following changes since commit c8ddb2713c624f432fa5fe3c7ecffcdda46ea0d4:

  Linux 2.6.37-rc1 (2010-11-01 07:54:12 -0400)

are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git upstream/blkfront

Jeremy Fitzhardinge (4):
      xen/blkfront: map REQ_FLUSH into a full barrier
      xen/blkfront: change blk_shadow.request to proper pointer
      xen/blkfront: Implement FUA with BLKIF_OP_WRITE_BARRIER
      xen/blkfront: cope with backend that fail empty BLKIF_OP_WRITE_BARRIER requests

 drivers/block/xen-blkfront.c |   55 ++++++++++++++++++++++++-----------------
 1 files changed, 32 insertions(+), 23 deletions(-)