From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:54680)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mjt@tls.msk.ru>) id 1SD98S-0000gm-6O
	for qemu-devel@nongnu.org; Thu, 29 Mar 2012 02:47:09 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <mjt@tls.msk.ru>) id 1SD98N-0007XN-K9
	for qemu-devel@nongnu.org; Thu, 29 Mar 2012 02:47:03 -0400
Received: from isrv.corpit.ru ([86.62.121.231]:55411)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mjt@tls.msk.ru>) id 1SD98N-0007X3-Cf
	for qemu-devel@nongnu.org; Thu, 29 Mar 2012 02:46:59 -0400
Message-ID: <4F740560.5080507@msgid.tls.msk.ru>
Date: Thu, 29 Mar 2012 10:46:56 +0400
From: Michael Tokarev <mjt@tls.msk.ru>
MIME-Version: 1.0
References: <1332949439-6781-1-git-send-email-stefanha@linux.vnet.ibm.com>
	<1332949439-6781-2-git-send-email-stefanha@linux.vnet.ibm.com>
In-Reply-To: <1332949439-6781-2-git-send-email-stefanha@linux.vnet.ibm.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH 1/2] ide: convert ide_sector_read() to
 asynchronous I/O
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Richard Davies <richard@arachsys.com>, Chris Webb <chris@arachsys.com>, qemu-devel@nongnu.org, Zhi Yong Wu <wuzhy@cn.ibm.com>, Paolo Bonzini <pbonzini@redhat.com>

On 28.03.2012 19:43, Stefan Hajnoczi wrote:
...

> void ide_sector_read(IDEState *s)
> {
...
> +    s->iov.iov_base = s->io_buffer;
> +    s->iov.iov_len  = n * BDRV_SECTOR_SIZE;
> +    qemu_iovec_init_external(&s->qiov, &s->iov, 1);
> +    bdrv_aio_readv(s->bs, sector_num, &s->qiov, n,
> +                   ide_sector_read_cb, s);
>  }
>  
> @@ -383,6 +383,8 @@ struct IDEState {
>      int cd_sector_size;
>      int atapi_dma; /* true if dma is requested for the packet cmd */
>      BlockAcctCookie acct;
> +    struct iovec iov;
> +    QEMUIOVector qiov;
>      /* ATA DMA state */
>      int io_buffer_size;
>      QEMUSGList sg;

You don't actually need iov here, it can be a local variable
just as well.  The same applies to ide_sector_write() in the
next patch.  The state structure usually holds stuff which
is actually needed to be keept across several calls, iov is
not one of them.

Thanks,

/mjt