From patchwork Tue Mar 21 03:16:23 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 9635923 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 81F9B6020B for ; Tue, 21 Mar 2017 03:25:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 765AD27D29 for ; Tue, 21 Mar 2017 03:25:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B48727D5D; Tue, 21 Mar 2017 03:25:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 189B227D29 for ; Tue, 21 Mar 2017 03:25:06 +0000 (UTC) Received: from localhost ([::1]:36428 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cqAPx-0007j4-2o for patchwork-qemu-devel@patchwork.kernel.org; Mon, 20 Mar 2017 23:25:05 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39699) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cqAIh-0001lx-9u for qemu-devel@nongnu.org; Mon, 20 Mar 2017 23:17:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cqAIg-0000Z8-Cu for qemu-devel@nongnu.org; Mon, 20 Mar 2017 23:17:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35540) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cqAIb-0000X3-K8; Mon, 20 Mar 2017 23:17:29 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AAB9E41A23; Tue, 21 Mar 2017 03:17:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com AAB9E41A23 Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=famz@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com AAB9E41A23 Received: from lemon.redhat.com (ovpn-8-61.pek2.redhat.com [10.72.8.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id F2A1178DD3; Tue, 21 Mar 2017 03:17:16 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Tue, 21 Mar 2017 11:16:23 +0800 Message-Id: <20170321031635.22123-5-famz@redhat.com> In-Reply-To: <20170321031635.22123-1-famz@redhat.com> References: <20170321031635.22123-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Tue, 21 Mar 2017 03:17:29 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH RFC 04/16] block: Propagate BLK_PERM_AIO_CONTEXT_CHANGE down the graph X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Paolo Bonzini , qemu-block@nongnu.org, Stefan Hajnoczi , Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP bdrv_set_aio_context can take care of children recursively, so it is okay to pass down the perm. Signed-off-by: Fam Zheng --- block.c | 18 ++++++++++-------- block/vvfat.c | 2 +- 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/block.c b/block.c index ae9327b..0190087 100644 --- a/block.c +++ b/block.c @@ -1670,7 +1670,8 @@ int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, #define DEFAULT_PERM_PASSTHROUGH (BLK_PERM_CONSISTENT_READ \ | BLK_PERM_WRITE \ | BLK_PERM_WRITE_UNCHANGED \ - | BLK_PERM_RESIZE) + | BLK_PERM_RESIZE \ + | BLK_PERM_AIO_CONTEXT_CHANGE) #define DEFAULT_PERM_UNCHANGED (BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH) void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, @@ -1713,21 +1714,22 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, perm |= BLK_PERM_CONSISTENT_READ; shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); } else { - /* We want consistent read from backing files if the parent needs it. + /* We want consistent read and aio context change from backing files if + * the parent needs it. * No other operations are performed on backing files. */ - perm &= BLK_PERM_CONSISTENT_READ; + perm &= BLK_PERM_CONSISTENT_READ | BLK_PERM_AIO_CONTEXT_CHANGE; - /* If the parent can deal with changing data, we're okay with a + /* If the parent can deal with changing aio context, we're okay too; + * If the parent can deal with changing data, we're okay with a * writable and resizable backing file. */ /* TODO Require !(perm & BLK_PERM_CONSISTENT_READ), too? */ + shared &= BLK_PERM_AIO_CONTEXT_CHANGE | BLK_PERM_WRITE; if (shared & BLK_PERM_WRITE) { - shared = BLK_PERM_WRITE | BLK_PERM_RESIZE; - } else { - shared = 0; + shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; } shared |= BLK_PERM_CONSISTENT_READ | BLK_PERM_GRAPH_MOD | - BLK_PERM_WRITE_UNCHANGED; + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_AIO_CONTEXT_CHANGE; } *nperm = perm; diff --git a/block/vvfat.c b/block/vvfat.c index af5153d..70ce452 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -3080,7 +3080,7 @@ static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c, if (c == s->qcow) { /* This is a private node, nobody should try to attach to it */ *nperm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE; - *nshared = BLK_PERM_WRITE_UNCHANGED; + *nshared = BLK_PERM_WRITE_UNCHANGED | BLK_PERM_AIO_CONTEXT_CHANGE; } else { /* The backing file is there so 'commit' can use it. vvfat doesn't * access it in any way. */