From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from [140.186.70.92] (port=34400 helo=eggs.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1OamnR-0005MJ-3F
	for qemu-devel@nongnu.org; Mon, 19 Jul 2010 05:38:02 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69)
	(envelope-from <kwolf@redhat.com>) id 1OamnM-0005Yx-Vs
	for qemu-devel@nongnu.org; Mon, 19 Jul 2010 05:38:01 -0400
Received: from mx1.redhat.com ([209.132.183.28]:23155)
	by eggs.gnu.org with esmtp (Exim 4.69)
	(envelope-from <kwolf@redhat.com>) id 1OamnM-0005Yq-My
	for qemu-devel@nongnu.org; Mon, 19 Jul 2010 05:37:56 -0400
Message-ID: <4C441CF0.3010909@redhat.com>
Date: Mon, 19 Jul 2010 11:37:52 +0200
From: Kevin Wolf <kwolf@redhat.com>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] [PATCH] block: Change bdrv_commit to handle multiple
	sectors at once
References: <1279297056-13392-1-git-send-email-kwolf@redhat.com>
	<20100716181633.GA29674@lst.de>
In-Reply-To: <20100716181633.GA29674@lst.de>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/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: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Christoph Hellwig <hch@lst.de>
Cc: qemu-devel@nongnu.org

Am 16.07.2010 20:16, schrieb Christoph Hellwig:
> On Fri, Jul 16, 2010 at 06:17:36PM +0200, Kevin Wolf wrote:
>> +    buf = qemu_malloc(2048 * BDRV_SECTOR_SIZE);
> 
> Please add a COMMIT_BUF_SIZE #define instead of the hardcoded 2048 in
> various places.
> 
>>      for (i = 0; i < total_sectors;) {
>> +        if (drv->bdrv_is_allocated(bs, i, 2048, &n)) {
>>  
>> +            if (bdrv_read(bs, i, buf, n) != 0) {
>> +                ret = -EIO;
>> +                goto ro_cleanup;
>> +            }
>> +
>> +            if (bdrv_write(bs->backing_hd, i, buf, n) != 0) {
>> +                ret = -EIO;
>> +                goto ro_cleanup;
>> +            }
>>          }
>> +        i += n;
> 
> Maybe it's just me, but I'd prefer n getting a more descriptive name
> (e.g. sector) and moving the increment of it into the for loop, e.g.
> 
> 	for (sector = 0; sector < total_sectors; sector += n) {
> 		if (!drv->bdrv_is_allocated(bs, i, 2048, &n))
> 			continue;
> 		...
> 	}

So you mean i should be renamed, not n, right? I'll change these points
in v2.

Kevin