From nobody Thu Nov 13 13:37:43 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1580421257137561.6313203024365; Thu, 30 Jan 2020 13:54:17 -0800 (PST) Received: from localhost ([::1]:39838 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ixHlQ-0002IS-19 for importer@patchew.org; Thu, 30 Jan 2020 16:54:16 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:33363) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ixHcT-0004sY-CS for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:45:02 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ixHcS-00044o-BI for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:45:01 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:54458 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ixHcS-00044C-82 for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:45:00 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-13-Rz-x4JnINymMcem07Z0-2A-1; Thu, 30 Jan 2020 16:44:56 -0500 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id E10F27341D; Thu, 30 Jan 2020 21:44:54 +0000 (UTC) Received: from localhost (ovpn-204-145.brq.redhat.com [10.40.204.145]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7B1B060BE1; Thu, 30 Jan 2020 21:44:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580420699; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/oPtPL8zf9tJoCJa4teoozK5YutntkpEjfe0LxqwwmU=; b=TLFbjOyDbxh3aZ8swKrdBGjno2rRmH+lAsL6kyaXMvOx3sIY9R+pFwtqnaDIKAlJqnLLKS dYIp2kDS6VddWLnXK7UiwdRI33jCEt+Emdx15WjEPXSi+6MBUoH4cuMsOrG0aSEadBCy5M Dd8RGs4KMGcsQSVzqBjsw9hUIWJFO3o= From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH v3 09/21] quorum: Add QuorumChild.to_be_replaced Date: Thu, 30 Jan 2020 22:44:19 +0100 Message-Id: <20200130214431.333510-10-mreitz@redhat.com> In-Reply-To: <20200130214431.333510-1-mreitz@redhat.com> References: <20200130214431.333510-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: Rz-x4JnINymMcem07Z0-2A-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" We will need this to verify that Quorum can let one of its children be replaced without breaking anything else. Signed-off-by: Max Reitz Reviewed-by: Vladimir Sementsov-Ogievskiy --- block/quorum.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/block/quorum.c b/block/quorum.c index 59cd524502..6a7224c9e4 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -67,6 +67,13 @@ typedef struct QuorumVotes { =20 typedef struct QuorumChild { BdrvChild *child; + + /* + * If set, check whether this node can be replaced without any + * other parent noticing: Unshare CONSISTENT_READ, and take the + * WRITE permission. + */ + bool to_be_replaced; } QuorumChild; =20 /* the following structure holds the state of one quorum instance */ @@ -1128,6 +1135,18 @@ static void quorum_child_perm(BlockDriverState *bs, = BdrvChild *c, uint64_t perm, uint64_t shared, uint64_t *nperm, uint64_t *nshared) { + BDRVQuorumState *s =3D bs->opaque; + int child_i =3D -1; + + if (c) { + for (child_i =3D 0; child_i < s->num_children; child_i++) { + if (s->children[child_i].child =3D=3D c) { + break; + } + } + assert(child_i < s->num_children); + } + *nperm =3D perm & DEFAULT_PERM_PASSTHROUGH; =20 /* @@ -1137,6 +1156,12 @@ static void quorum_child_perm(BlockDriverState *bs, = BdrvChild *c, *nshared =3D (shared & (BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED)) | DEFAULT_PERM_UNCHANGED; + + if (child_i >=3D 0 && s->children[child_i].to_be_replaced) { + /* Prepare for sudden data changes */ + *nperm |=3D BLK_PERM_WRITE; + *nshared &=3D ~BLK_PERM_CONSISTENT_READ; + } } =20 static const char *const quorum_strong_runtime_opts[] =3D { --=20 2.24.1