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From: Alberto Garcia <berto@igalia.com>
In-Reply-To: <e1d4fa92-9f84-080c-04e3-4fc9b683c11d@virtuozzo.com>
References: <20181101182738.70462-1-vsementsov@virtuozzo.com>
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	<w514lcudz3y.fsf@maestria.local.igalia.com>
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Date: Tue, 06 Nov 2018 16:30:40 +0100
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Subject: Re: [Qemu-devel] [Qemu-block] [PATCH 6/7] qcow2: aio support for
 compressed cluster read
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To: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "qemu-block@nongnu.org" <qemu-block@nongnu.org>
Cc: "kwolf@redhat.com" <kwolf@redhat.com>, Denis Lunev <den@virtuozzo.com>, "mreitz@redhat.com" <mreitz@redhat.com>

On Tue 06 Nov 2018 04:13:58 PM CET, Vladimir Sementsov-Ogievskiy wrote:
> 06.11.2018 18:06, Alberto Garcia wrote:
>> On Thu 01 Nov 2018 07:27:37 PM CET, Vladimir Sementsov-Ogievskiy wrote:
>>
>>> +    buf = g_try_malloc(csize);
>>> +    if (!buf) {
>>> +        return -ENOMEM;
>>> +    }
>>> +    iov.iov_base = buf;
>>> +    iov.iov_len = csize;
>>> +    qemu_iovec_init_external(&local_qiov, &iov, 1);
>>>   
>>> -        iov.iov_base = s->cluster_data;
>>> -        iov.iov_len = csize;
>>> -        qemu_iovec_init_external(&local_qiov, &iov, 1);
>>> +    out_buf = qemu_blockalign(bs, s->cluster_size);
>> You should also check whether out_buf is NULL, shouldn't you?
>
> No, it will abort on fail. qemu_try_blockalign result should be
> checked.

Is there any reason why some parts of the QEMU code use qemu_blockalign
and others qemu_try_blockalign() ? From what I can see it seems to be up
to whoever wrote it...

Berto