Hi Jens,

this series does some refactoring and then adds support to return errors
from add_disk (rebasing a patch from Luis).  I think that alone is a huge
improvement as it leaves a disk for which add_disk failed in a defined
status, but the real improvement will be actually handling the errors in
the drivers.  This series contains two trivial conversions.  Luis has
a tree with conversions for all drivers in the tree, which will be fed
incrementally once this goes in.  Hopefully we can convert all the
commonly used drivers in this merge window.

This series sits on top of:

   "ensure each gendisk always has a request_queue reference v2"

A git tree is available here:

    git://git.infradead.org/users/hch/block.git

Gitweb:

    http://git.infradead.org/users/hch/block.git/shortlog/refs/heads/add-disk-error-handling

Diffstat:
 block/blk-integrity.c         |   12 +-
 block/blk-sysfs.c             |    9 --
 block/blk.h                   |    7 -
 block/disk-events.c           |    7 -
 block/genhd.c                 |  186 ++++++++++++++++++++++--------------------
 drivers/block/null_blk/main.c |    3 
 drivers/block/virtio_blk.c    |    7 +
 include/linux/genhd.h         |    8 -
 8 files changed, 125 insertions(+), 114 deletions(-)