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Date: Wed, 27 Nov 2013 08:56:55 +0800
From: Fam Zheng <famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v5 5/7] block: Parse "backing" option to
 reference existing BDS
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kwolf@redhat.com, hbrock@redhat.com, qemu-devel@nongnu.org, rjones@redhat.com, imain@redhat.com, stefanha@redhat.com

On 2013=E5=B9=B411=E6=9C=8827=E6=97=A5 00:18, Paolo Bonzini wrote:
> Il 26/11/2013 05:05, Fam Zheng ha scritto:
>> +    if (backing_bs && *backing_bs !=3D '\0') {
>> +        bs->backing_hd =3D 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, an=
d
> not to all backing files?
>

Good point, thanks.

Fam