Re: [Qemu-devel] [PATCH v9 05/31] block: Respect backing bs in bdrv_refresh_filename

[Eric Blake <eblake@redhat.com>]

On 06/27/2018 07:07 PM, Max Reitz wrote:
> Basically, bdrv_refresh_filename() should respect all children of a
> BlockDriverState. However, generally those children are driver-specific,
> so this function cannot handle the general case. On the other hand,
> there are only few drivers which use other children than @file and
> @backing (that being vmdk, quorum, and blkverify).
> 
> Most block drivers only use @file and/or @backing (if they use any
> children at all). Both can be implemented directly in
> bdrv_refresh_filename.
> 
> The user overriding the file's filename is already handled, however, the
> user overriding the backing file is not. If this is done, opening the
> BDS with the plain filename of its file will not be correct, so we may
> not set bs->exact_filename in that case.
> 
> iotest 051 contains test cases for overriding the backing file, and so
> its output changes with this patch applied.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>   block.c                       | 30 +++++++++++++++++++++++++++++-
>   tests/qemu-iotests/051.out    |  8 ++++----
>   tests/qemu-iotests/051.pc.out |  8 ++++----
>   3 files changed, 37 insertions(+), 9 deletions(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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