Re: [Qemu-devel] [PATCH v9 01/31] block: Use bdrv_refresh_filename() to pull

[Eric Blake <eblake@redhat.com>]

On 06/27/2018 07:07 PM, Max Reitz wrote:
> Before this patch, bdrv_refresh_filename() is used in a pushing manner:
> Whenever the BDS graph is modified, the parents of the modified edges
> are supposed to be updated (recursively upwards).  However, that is
> unviable, considering that we want child changes not to concern parents.

s/unviable/nonviable/

> 
> Also, in the long run we want a pull model anyway: Here, we would have a
> bdrv_filename() function which returns a BDS's filename, freshly
> constructed.
> 
> This patch is an intermediate step.  It adds bdrv_refresh_filename()
> calls before every place a BDS.filename value is used.  The only
> exceptions are protocol drivers that use their own filename, which
> clearly would not profit from refreshing that filename before.
> 
> Also, bdrv_get_encrypted_filename() is removed along the way (as a user
> of BDS.filename), since it is completely unused.
> 
> In turn, all of the calls to bdrv_refresh_filename() before this patch
> are removed, because we no longer have to call this function on graph
> changes.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
Reviewed-by: Eric Blake <eblake@redhat.com>

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Eric Blake, Principal Software Engineer
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