Open Stack

Hi, I'd like you to take a look at this patch for potential
DocImpact.
https://review.openstack.org/35214

Log:
commit 1549f33442f7eb861fffb67987de2d8f2e397327
Author: Chet Burgess <cfb at metacloud.com>
Date:   Fri Jun 28 21:21:36 2013 +0000

    Support setting block size for block devives
    
    cinder now supports backend with different block sizes. Sometimes
    we need to set a specific block size or operations against the
    backend will result in I/O errors. Additionally its a good idea
    to tune the block sizes to the correct size as it can improve I/O
    performance.
    
    The basic disk configuration for libvrit now supports setting the
    logical and physical block size of devices. We pull the block size
    from the volume metadata and store it in the connection_info of
    the block_device_mapping table for later use.
    
    By default it does not set the block sizes which defaults to
    512 bytes.
    
    DocImpact:
    This feature requires libvirt 0.10.2+ and the QEMU or KVM
    hpypervisor. If a volume has a custom block size, the hypervisor
    and libvirt version are checked during the attach_volume call. If
    the hypervisor is not supported or the libvirt version is too old
    the attach is aborted and an exception is raised.
    
    Change-Id: I77adc96b340680218f82bbef8f9ec14711d26a7f
    Fixes Bug #1195913

Automatically generated bug (please review):
https://bugs.launchpad.net/bugs/1197449