Re: [Qemu-devel] [Qemu-block] [PATCH v3 07/38] block/quorum: Implement bdrv_is_inserted()

[Max Reitz <mreitz@redhat.com>]

On 04.06.2015 14:37, Alberto Garcia wrote:
> On Wed 03 Jun 2015 09:43:48 PM CEST, Max Reitz wrote:
>> bdrv_is_inserted() should be invoked recursively on the children of
>> quorum.
>>
>> Signed-off-by: Max Reitz <mreitz@redhat.com>
>> Reviewed-by: Eric Blake <eblake@redhat.com>
>> ---
>> +static bool quorum_is_inserted(BlockDriverState *bs)
>> +{
>> +    BDRVQuorumState *s = bs->opaque;
>> +    int i;
>> +
>> +    for (i = 0; i < s->num_children; i++) {
>> +        if (!bdrv_is_inserted(s->bs[i])) {
>> +            return false;
>> +        }
>> +    }
>> +
>> +    return true;
>> +}
>> +
> I wonder if it can actually happen that only some of the BDS are
> inserted :-?

I'm actually able to start Quorum on an empty DVD drive:

$ x86_64-softmmu/qemu-system-x86_64 -drive 
if=none,id=drv,driver=quorum,children.0.file.filename=/dev/sr0,children.0.driver=raw,children.1.file.filename=test.qcow2,vote-threshold=1 
-qmp stdio
{"QMP": {"version": {"qemu": {"micro": 50, "minor": 3, "major": 2}, 
"package": ""}, "capabilities": []}}
{'execute':'qmp_capabilities'}
{"return": {}}
{'execute':'human-monitor-command','arguments':{'command-line':'qemu-io 
drv "write 0 512"'}}
write failed: No medium found
{"return": ""}

(note that on master, the write is successful (???), but you do get: 
{"timestamp": {"seconds": 1433518087, "microseconds": 527326}, "event": 
"QUORUM_REPORT_BAD", "data": {"node-name": "", "sectors-count": 1, 
"sector-num": 0, "error": "No medium found"}})

Thank you for reviewing! :-)

Max