From patchwork Tue Nov 3 10:58:43 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Congyang X-Patchwork-Id: 539307 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 A69B714090A for ; Tue, 3 Nov 2015 22:03:08 +1100 (AEDT) Received: from localhost ([::1]:47011 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtZMo-0000dC-NP for incoming@patchwork.ozlabs.org; Tue, 03 Nov 2015 06:03:06 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37405) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtZKD-0004Si-K0 for qemu-devel@nongnu.org; Tue, 03 Nov 2015 06:00:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZtZK9-0002jd-LV for qemu-devel@nongnu.org; Tue, 03 Nov 2015 06:00:25 -0500 Received: from [59.151.112.132] (port=5716 helo=heian.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtZK9-0002hQ-5J; Tue, 03 Nov 2015 06:00:21 -0500 Received: from bogon (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 03 Nov 2015 18:59:58 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id tA3AxagU019080; Tue, 3 Nov 2015 18:59:36 +0800 Received: from G08FNSTD140052.g08.fujitsu.local (10.167.226.52) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Tue, 3 Nov 2015 19:00:12 +0800 From: Wen Congyang To: qemu devel , Fam Zheng , Max Reitz , Paolo Bonzini , Stefan Hajnoczi Date: Tue, 3 Nov 2015 18:58:43 +0800 Message-ID: <1446548329-17475-7-git-send-email-wency@cn.fujitsu.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1446548329-17475-1-git-send-email-wency@cn.fujitsu.com> References: <1446548329-17475-1-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 , Jiang Yunhong , Dong Eddie , "Dr. David Alan Gilbert" , "Michael R. Hines" Subject: [Qemu-devel] [PATCH v11 06/12] block: make bdrv_put_ref_bh_schedule() as a public API 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.c | 25 +++++++++++++++++++++++++ blockdev.c | 37 ++++++------------------------------- include/block/block.h | 1 + 3 files changed, 32 insertions(+), 31 deletions(-) diff --git a/block.c b/block.c index 32ed776..9a1c20e 100644 --- a/block.c +++ b/block.c @@ -3508,6 +3508,31 @@ void bdrv_unref(BlockDriverState *bs) } } +typedef struct { + QEMUBH *bh; + BlockDriverState *bs; +} BDRVPutRefBH; + +static void bdrv_put_ref_bh(void *opaque) +{ + BDRVPutRefBH *s = opaque; + + bdrv_unref(s->bs); + qemu_bh_delete(s->bh); + g_free(s); +} + +/* Release a BDS reference in a BH */ +void bdrv_put_ref_bh_schedule(BlockDriverState *bs) +{ + BDRVPutRefBH *s; + + s = g_new(BDRVPutRefBH, 1); + s->bh = qemu_bh_new(bdrv_put_ref_bh, s); + s->bs = bs; + qemu_bh_schedule(s->bh); +} + struct BdrvOpBlocker { Error *reason; QLIST_ENTRY(BdrvOpBlocker) list; diff --git a/blockdev.c b/blockdev.c index bd13669..9d0b3ea 100644 --- a/blockdev.c +++ b/blockdev.c @@ -278,37 +278,6 @@ static void bdrv_format_print(void *opaque, const char *name) error_printf(" %s", name); } -typedef struct { - QEMUBH *bh; - BlockDriverState *bs; -} BDRVPutRefBH; - -static void bdrv_put_ref_bh(void *opaque) -{ - BDRVPutRefBH *s = opaque; - - bdrv_unref(s->bs); - qemu_bh_delete(s->bh); - g_free(s); -} - -/* - * Release a BDS reference in a BH - * - * It is not safe to use bdrv_unref() from a callback function when the callers - * still need the BlockDriverState. In such cases we schedule a BH to release - * the reference. - */ -static void bdrv_put_ref_bh_schedule(BlockDriverState *bs) -{ - BDRVPutRefBH *s; - - s = g_new(BDRVPutRefBH, 1); - s->bh = qemu_bh_new(bdrv_put_ref_bh, s); - s->bs = bs; - qemu_bh_schedule(s->bh); -} - static int parse_block_error_action(const char *buf, bool is_read, Error **errp) { if (!strcmp(buf, "ignore")) { @@ -2557,6 +2526,12 @@ static void block_job_cb(void *opaque, int ret) block_job_event_completed(bs->job, msg); } + + /* + * It is not safe to use bdrv_unref() from a callback function when the + * callers still need the BlockDriverState. In such cases we schedule + * a BH to release the reference. + */ bdrv_put_ref_bh_schedule(bs); } diff --git a/include/block/block.h b/include/block/block.h index 601a5de..cccda1d 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -507,6 +507,7 @@ void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, BlockDriverState *child_bs, const BdrvChildRole *child_role); +void bdrv_put_ref_bh_schedule(BlockDriverState *bs); bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);