Re: [Qemu-devel] [PATCH v4 02/16] block: Add blk_new_open()

[Stefan Hajnoczi <stefanha@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1316 bytes --]

On Thu, Feb 05, 2015 at 01:58:11PM -0500, Max Reitz wrote:
> blk_new_with_bs() creates a BlockBackend with an empty BlockDriverState
> attached to it. Empty BDSs are not nice, therefore add an alternative
> function which combines blk_new_with_bs() with bdrv_open().
> 
> Note: In contrast to bdrv_open() which takes a BlockDriver parameter,
> blk_new_open() does not take such a parameter. This is because
> bdrv_open() opens a BlockDriverState, therefore it is natural to be able
> to set the BlockDriver for that BDS. The fact that bdrv_open() can open
> more than a single BDS is merely some form of a byproduct.
> 
> blk_new_open() on the other hand is intended to be used to create a
> whole tree of BlockDriverStates. Therefore, setting a single BlockDriver
> does not make much sense. Instead, the drivers to be used for each of
> the nodes must be configured through the "options" QDict; including the
> driver of the root BDS.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block/block-backend.c          | 34 ++++++++++++++++++++++++++++++++++
>  include/sysemu/block-backend.h |  3 +++
>  2 files changed, 37 insertions(+)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]