Re: [Qemu-devel] [PATCH 3/4] qcow2: Add overlap-check.template option

[Max Reitz <mreitz@redhat.com>]

On 20.08.2014 21:22, Eric Blake wrote:
> On 08/20/2014 11:59 AM, Max Reitz wrote:
>> Being able to set the overlap-check option to a string and then refine
>> it via the overlap-check.* options is a nice idea for the command line
>> but does not work so well for non-flattened dicts. In that case, one can
>> only specify either but not both, so add a field to overlap-check.*
>> which does the same as directly specifying overlap-check but can be used
>> in conjunction with the other fields in non-flattened dicts.
>>
>> Signed-off-by: Max Reitz <mreitz@redhat.com>
>> ---
>>   block/qcow2.c | 24 ++++++++++++++++++++++--
>>   block/qcow2.h |  1 +
>>   2 files changed, 23 insertions(+), 2 deletions(-)
>>
>> diff --git a/block/qcow2.c b/block/qcow2.c
>> index c64d611..c6099b5 100644
>> --- a/block/qcow2.c
>> +++ b/block/qcow2.c
>> @@ -403,6 +403,12 @@ static QemuOptsList qcow2_runtime_opts = {
>>                       "templates (none, constant, cached, all)",
>>           },
>>           {
>> +            .name = QCOW2_OPT_OVERLAP_TEMPLATE,
>> +            .type = QEMU_OPT_STRING,
>> +            .help = "Selects which overlap checks to perform from a range of "
>> +                    "templates (none, constant, cached, all)",
>> +        },
>> +        {
> Okay, I see where this is headed.  The QMP will allow either
> 'overlap-check':'all' (resolve all defaults according to a template
> name), or 'overlap-check':{'template':'all','inactive-l1':'none'} (that
> is, a struct, where the struct also sets a default but also provides
> per-item overrides).

Yes, it's my fault for not thinking about how well the second case would 
work for non-flattened dicts when I originally introduced these options.

Max

> It took me a couple of reads of this in tandem
> with 4/4, but it looks correct.