Re: [Qemu-devel] [PATCH v7 for-2.12 05/25] block: Respect backing bs in bdrv_refresh_filename

[Alberto Garcia]

On Mon 20 Nov 2017 09:09:44 PM CET, 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.
>
> iotests 051 and 191 contain test cases for overwriting the backing file,
> and so their output changes with this patch applied (which I consider a
> good thing). Note that in the case of 191, the implicitly opened
> (non-overridden) base file is included in the json:{} filename as well
> -- this will be remedied by a later patch.
>
> Signed-off-by: Max Reitz <address@hidden>

Reviewed-by: Alberto Garcia <address@hidden>

Berto