Re: [Qemu-devel] [PATCH v5 5/7] block: Parse "backing" option to reference existing BDS

[Fam Zheng <famz@redhat.com>]

On 2013年11月27日 00:18, Paolo Bonzini wrote:
> Il 26/11/2013 05:05, Fam Zheng ha scritto:
>> +    if (backing_bs && *backing_bs != '\0') {
>> +        bs->backing_hd = bdrv_find(backing_bs);
>> +        if (!bs->backing_hd) {
>> +            error_setg(errp, "Backing device not found: %s", backing_bs);
>> +            return -ENOENT;
>> +        }
>> +        bdrv_ref(bs->backing_hd);
>> +        assert(!bs->backing_blocker);
>> +        error_setg(&bs->backing_blocker,
>> +                   "device is used as backing hd of '%s'",
>> +                   bs->device_name);
>> +        bdrv_op_block_all(bs->backing_hd, bs->backing_blocker);
>
> Why should this blocker only apply to the "named backing file" case, and
> not to all backing files?
>

Good point, thanks.

Fam