From patchwork Thu Oct 22 06:32:57 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 534254 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 98B6B141317 for ; Thu, 22 Oct 2015 17:41:44 +1100 (AEDT) Received: from localhost ([::1]:56880 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zp9ZG-0002QT-C7 for incoming@patchwork.ozlabs.org; Thu, 22 Oct 2015 02:41:42 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52226) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zp9Rl-0001wf-0V for qemu-devel@nongnu.org; Thu, 22 Oct 2015 02:33:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zp9Rk-0008JV-8T for qemu-devel@nongnu.org; Thu, 22 Oct 2015 02:33:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52026) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zp9Rf-0008Ih-Vw; Thu, 22 Oct 2015 02:33:52 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id 8F5B540; Thu, 22 Oct 2015 06:33:51 +0000 (UTC) Received: from fam-t430.redhat.com (vpn1-4-248.pek2.redhat.com [10.72.4.248]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t9M6X1FU013259; Thu, 22 Oct 2015 02:33:47 -0400 From: Fam Zheng To: qemu-devel@nongnu.org Date: Thu, 22 Oct 2015 14:32:57 +0800 Message-Id: <1445495580-32129-10-git-send-email-famz@redhat.com> In-Reply-To: <1445495580-32129-1-git-send-email-famz@redhat.com> References: <1445495580-32129-1-git-send-email-famz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, pbonzini@redhat.com, jcody@redhat.com, stefanha@redhat.com, qemu-block@nongnu.org Subject: [Qemu-devel] [PATCH v6 09/12] block: Add "drained begin/end" for internal snapshot 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 This ensures the atomicity of the transaction by avoiding processing of external requests such as those from ioeventfd. state->bs is assigned right after bdrv_drained_begin. Because it was used as the flag for deletion or not in abort, now we need a separate flag - InternalSnapshotState.created. Signed-off-by: Fam Zheng --- blockdev.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/blockdev.c b/blockdev.c index 52f44b2..adc0e69 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1370,6 +1370,7 @@ typedef struct InternalSnapshotState { BlockDriverState *bs; AioContext *aio_context; QEMUSnapshotInfo sn; + bool created; } InternalSnapshotState; static void internal_snapshot_prepare(BlkTransactionState *common, @@ -1414,6 +1415,9 @@ static void internal_snapshot_prepare(BlkTransactionState *common, } bs = blk_bs(blk); + state->bs = bs; + bdrv_drained_begin(bs); + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) { return; } @@ -1465,7 +1469,7 @@ static void internal_snapshot_prepare(BlkTransactionState *common, } /* 4. succeed, mark a snapshot is created */ - state->bs = bs; + state->created = true; } static void internal_snapshot_abort(BlkTransactionState *common) @@ -1476,7 +1480,7 @@ static void internal_snapshot_abort(BlkTransactionState *common) QEMUSnapshotInfo *sn = &state->sn; Error *local_error = NULL; - if (!bs) { + if (!state->created) { return; } @@ -1497,6 +1501,7 @@ static void internal_snapshot_clean(BlkTransactionState *common) common, common); if (state->aio_context) { + bdrv_drained_end(state->bs); aio_context_release(state->aio_context); } }