From nobody Mon Feb 9 08:19:40 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.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 (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1572126322; cv=none; d=zoho.com; s=zohoarc; b=kzXQlC50284gKQWNUyiGlMzcBoXVPeEMZQhjeddQBKVk6vvL5oaOV47BRipbxVZWiv4qTpoIb5S/bBG/8FuqeAyhFbycU9QjC/VZ2NDcGyxnac0McmP5Pzk53nKRaOQARbdfMfri8Dp9pNvcS6OS/jVubzyy0uhw+7w2+9OHVLI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1572126322; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=lai4II5riXAG+qlx1gVox8WzNlTJA6AvF/a0K8JY1/8=; b=dEhjtrG8LDX9vRj7pq2hE7b/RHIdg00P427W3ADZzDikJfCIEDKorn2pSbPwaueNwFhSCmJBpxkw1OvOUFBB2gRz2SODLvtOWYZYarmAHsuThFYMWdpfvjf5+J5/kLaa52n0RMmAg44vtQHRYHSZZjjQ6eFC5encGhW2XJVu638= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1572126322228682.0347378149835; Sat, 26 Oct 2019 14:45:22 -0700 (PDT) Received: from localhost ([::1]:42658 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iOTs8-0005c6-Ei for importer@patchew.org; Sat, 26 Oct 2019 17:45:20 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60475) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iOTa3-0000d2-L9 for qemu-devel@nongnu.org; Sat, 26 Oct 2019 17:26:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iOTZz-0005Vy-Rl for qemu-devel@nongnu.org; Sat, 26 Oct 2019 17:26:39 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:42556) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1iOTZy-0005Hk-Sz; Sat, 26 Oct 2019 17:26:35 -0400 Received: from 87-100-137-117.bb.dnainternet.fi ([87.100.137.117] helo=perseus.local) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim) id 1iOTZI-00045k-MG; Sat, 26 Oct 2019 23:25:52 +0200 Received: from berto by perseus.local with local (Exim 4.92) (envelope-from ) id 1iOTZ0-0001P4-2m; Sun, 27 Oct 2019 00:25:34 +0300 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=lai4II5riXAG+qlx1gVox8WzNlTJA6AvF/a0K8JY1/8=; b=nrxDPTqlRE4iwTJYcC5E+us9viYt6S52X/N6Ly0DPPoA6VyG+RtP8Nix4Fge8sbRzq7r/msGzKLnEJCOZ8i5nMrkggLAFxfuCxw4GaxECqa+jQq+MuUcJHr7aqEuZcBOuDez826hfWfj6lHq/OpEUBhskFFANFbA74uJti31psTN6/jBMmANoVhFCHS22gK3O84S8cb81KUaAECNCMlSz1igKlJ/2gqa9blMZPH6y9geYHjdR7wbrZ8vOQL+w+/86MbGalXiOkDqVHIuv8+S4WCewxfl21rtN616fuWkDRnXBoHEsRPux0YGgMqUUJm/xDk1R8ctGYsU1llU7gyJMA==; From: Alberto Garcia To: qemu-devel@nongnu.org Subject: [RFC PATCH v2 02/26] qcow2: Split cluster_needs_cow() out of count_cow_clusters() Date: Sun, 27 Oct 2019 00:25:04 +0300 Message-Id: <574b670e016379e8b4230b52d9b46c1d97d9486b.1572125022.git.berto@igalia.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x (no timestamps) [generic] [fuzzy] X-Received-From: 178.60.130.6 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 , Anton Nefedov , Alberto Garcia , qemu-block@nongnu.org, Max Reitz , Vladimir Sementsov-Ogievskiy , "Denis V . Lunev" 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 are going to need it in other places. Signed-off-by: Alberto Garcia Reviewed-by: Vladimir Sementsov-Ogievskiy --- block/qcow2-cluster.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 6c1dcdc781..aa1010a515 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1068,6 +1068,24 @@ static void calculate_l2_meta(BlockDriverState *bs, = uint64_t host_offset, QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); } =20 +/* Returns true if writing to a cluster requires COW */ +static bool cluster_needs_cow(BlockDriverState *bs, uint64_t l2_entry) +{ + switch (qcow2_get_cluster_type(bs, l2_entry)) { + case QCOW2_CLUSTER_NORMAL: + if (l2_entry & QCOW_OFLAG_COPIED) { + return false; + } + case QCOW2_CLUSTER_UNALLOCATED: + case QCOW2_CLUSTER_COMPRESSED: + case QCOW2_CLUSTER_ZERO_PLAIN: + case QCOW2_CLUSTER_ZERO_ALLOC: + return true; + default: + abort(); + } +} + /* * Returns the number of contiguous clusters that can be used for an alloc= ating * write, but require COW to be performed (this includes yet unallocated s= pace, @@ -1080,25 +1098,11 @@ static int count_cow_clusters(BlockDriverState *bs,= int nb_clusters, =20 for (i =3D 0; i < nb_clusters; i++) { uint64_t l2_entry =3D be64_to_cpu(l2_slice[l2_index + i]); - QCow2ClusterType cluster_type =3D qcow2_get_cluster_type(bs, l2_en= try); - - switch(cluster_type) { - case QCOW2_CLUSTER_NORMAL: - if (l2_entry & QCOW_OFLAG_COPIED) { - goto out; - } + if (!cluster_needs_cow(bs, l2_entry)) { break; - case QCOW2_CLUSTER_UNALLOCATED: - case QCOW2_CLUSTER_COMPRESSED: - case QCOW2_CLUSTER_ZERO_PLAIN: - case QCOW2_CLUSTER_ZERO_ALLOC: - break; - default: - abort(); } } =20 -out: assert(i <=3D nb_clusters); return i; } --=20 2.20.1