From patchwork Tue Jun 30 03:34:34 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Congyang X-Patchwork-Id: 489481 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id CC970140913 for ; Tue, 30 Jun 2015 13:34:02 +1000 (AEST) Received: from localhost ([::1]:44805 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9mJ7-0006gj-0R for incoming@patchwork.ozlabs.org; Mon, 29 Jun 2015 23:34:01 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52771) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9mGZ-0001YB-5E for qemu-devel@nongnu.org; Mon, 29 Jun 2015 23:31:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z9mGY-0008Oh-5I for qemu-devel@nongnu.org; Mon, 29 Jun 2015 23:31:23 -0400 Received: from [59.151.112.132] (port=38433 helo=heian.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9mGX-0008EB-Hh; Mon, 29 Jun 2015 23:31:22 -0400 X-IronPort-AV: E=Sophos;i="5.13,665,1427731200"; d="scan'208";a="97890031" Received: from unknown (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 30 Jun 2015 11:35:04 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id t5U3TO6e027991; Tue, 30 Jun 2015 11:29:24 +0800 Received: from G08FNSTD140052.g08.fujitsu.local (10.167.226.52) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Tue, 30 Jun 2015 11:31:04 +0800 From: Wen Congyang To: qemu devel , Fam Zheng , Max Reitz , Paolo Bonzini Date: Tue, 30 Jun 2015 11:34:34 +0800 Message-ID: <1435635285-5804-7-git-send-email-wency@cn.fujitsu.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1435635285-5804-1-git-send-email-wency@cn.fujitsu.com> References: <1435635285-5804-1-git-send-email-wency@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.52] X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 59.151.112.132 Cc: Kevin Wolf , qemu block , Lai Jiangshan , Jiang Yunhong , Dong Eddie , "Dr. David Alan Gilbert" , Stefan Hajnoczi , Yang Hongyang Subject: [Qemu-devel] [PATCH COLO-BLOCK v7 06/17] introduce a new API to enable/disable attach device model X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Signed-off-by: Wen Congyang --- block/block-backend.c | 24 ++++++++++++++++++++++++ include/sysemu/block-backend.h | 2 ++ 2 files changed, 26 insertions(+) diff --git a/block/block-backend.c b/block/block-backend.c index aee8a12..72d8b2c 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -344,6 +344,30 @@ void *blk_get_attached_dev(BlockBackend *blk) } /* + * Disable to attach a device mode to @blk. + * Return 0 on success, -EBUSY when a device model is attached already. + */ +int blk_disable_attach_dev(BlockBackend *blk) +{ + if (blk->dev) { + return blk->dev == (void *)-1 ? 0 : -EBUSY; + } + + blk->dev = (void *)-1; + return 0; +} + +/* + * Enable to attach a device mode to @blk. + */ +void blk_enable_attach_dev(BlockBackend *blk) +{ + if (blk->dev == (void *)-1) { + blk->dev = NULL; + } +} + +/* * Set @blk's device model callbacks to @ops. * @opaque is the opaque argument to pass to the callbacks. * This is for use by device models. diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index 8fc960f..7619a9f 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -80,6 +80,8 @@ int blk_attach_dev(BlockBackend *blk, void *dev); void blk_attach_dev_nofail(BlockBackend *blk, void *dev); void blk_detach_dev(BlockBackend *blk, void *dev); void *blk_get_attached_dev(BlockBackend *blk); +int blk_disable_attach_dev(BlockBackend *blk); +void blk_enable_attach_dev(BlockBackend *blk); void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque); int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, int nb_sectors);