Re: [PATCH v7 22/32] qcow2: Add subcluster support to zero_in_l2_slice()

[Eric Blake]

On 5/25/20 1:08 PM, Alberto Garcia wrote:
> The QCOW_OFLAG_ZERO bit that indicates that a cluster reads as
> zeroes is only used in standard L2 entries. Extended L2 entries use
> individual 'all zeroes' bits for each subcluster.
>
> This must be taken into account when updating the L2 entry and also
> when deciding that an existing entry does not need to be updated.
>
> Signed-off-by: Alberto Garcia <address@hidden>
> ---
>   block/qcow2-cluster.c | 36 +++++++++++++++++++-----------------
>   1 file changed, 19 insertions(+), 17 deletions(-)

Reviewed-by: Eric Blake <address@hidden>

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Eric Blake, Principal Software Engineer
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