From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:35637)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1Ynkqd-00076j-1r
	for qemu-devel@nongnu.org; Thu, 30 Apr 2015 05:33:36 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1Ynkqc-0005uY-9J
	for qemu-devel@nongnu.org; Thu, 30 Apr 2015 05:33:34 -0400
Date: Thu, 30 Apr 2015 11:33:26 +0200
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20150430093310.GA3368@noname.redhat.com>
References: <5541F1B3.6040501@cn.fujitsu.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <5541F1B3.6040501@cn.fujitsu.com>
Subject: Re: [Qemu-devel] Question about block driver
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: Wen Congyang <wency@cn.fujitsu.com>
Cc: qemu-block@nongnu.org, Fam Zheng <famz@redhat.com>, qemu-devl <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

[Cc: qemu-block]

Am 30.04.2015 um 11:11 hat Wen Congyang geschrieben:
> Some drivers use bdrv_open, while the other dirvers use bdrv_file_open().
> What is the difference between bdrv_open() and bdrv_file_open()?

bdrv_file_open() is used by protocol drivers that don't need any other
driver to work (e.g. raw-posix), bdrv_open() is used by format drivers
that need a bs->file (e.g. raw or qcow2).

They used to have different parameters originally, but nowadays that's
the only difference.

Kevin