From nobody Mon Feb 9 12:29:29 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=1572129128; cv=none; d=zoho.com; s=zohoarc; b=WwwWERp9FcM1jHWdeYBNqMuYng2ppxvoLHksYtscOismn9lXWaAvLEPZwaeirbi+2FSUDKhb9rYH3YAitz6WflsgDAa+FwjbjSAW1pkNebayrrx6+/mWNRfmMxd1LlBMC9/j+J9urpfNCWoEn1pjnfuvWcw1wRpQRvfXB6kd5gg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1572129128; 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=xwaAM/d5xwG96LuTjF/2zt7GMq/uOL/UjAXAavz3Mr0=; b=V08Woe+0x5IhGjiZccfPyTYnMFjm6JjMXgjcCgwfcs29WL3I5213pJZNTVTefFOmz0zBA663Bvm5SZ/I58RoBBB39Y2rKx0SXurVUsZMe/GEWGEAQnzVVKSakeogcHzTMpiSTXR2412oA56erGyDn11pR4TrbYDUjXDNbNjzKpw= 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 1572129128851311.23107115162907; Sat, 26 Oct 2019 15:32:08 -0700 (PDT) Received: from localhost ([::1]:43222 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iOUbP-0004Z9-If for importer@patchew.org; Sat, 26 Oct 2019 18:32:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60287) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iOTZw-0000Vc-By for qemu-devel@nongnu.org; Sat, 26 Oct 2019 17:26:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iOTZv-0005Qt-4v for qemu-devel@nongnu.org; Sat, 26 Oct 2019 17:26:32 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:42495) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1iOTZu-0005Es-Sr; Sat, 26 Oct 2019 17:26:31 -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-00045s-MH; Sat, 26 Oct 2019 23:25:52 +0200 Received: from berto by perseus.local with local (Exim 4.92) (envelope-from ) id 1iOTZ0-0001PE-AU; 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=xwaAM/d5xwG96LuTjF/2zt7GMq/uOL/UjAXAavz3Mr0=; b=r3VJehp7i+DMP29o4IkPyGyYjX93RT50s7M4ZkxDKY5AAdN5B2jqMgFaPkOGgSML8wlV4CPUcaKnWxd8RlyYGNSlZ0N+IL0OP8MYXaJdy/TLIjvgAa655KZ7beifdZC/HXngsqg0HwmiHLeOTTfgsE6quCRzSq+tuZxcnPu5f6sjlBsL/6zOllzffur7yY6QOq3d99dM36H8+gFxUIF25EH7AE9kOhJZuiQh/tc7LY5uXbaXVEX1kLUoYU85nvZ51QEyvRDK5rGqYGDEi4TKJFXjGGlU0Sz4wo9fbl3A1BRbA0nrmtHICUDOPH1hkokSb94iwrNWZvT0CrcW/5aJ9Q==; From: Alberto Garcia To: qemu-devel@nongnu.org Subject: [RFC PATCH v2 07/26] qcow2: Add subcluster-related fields to BDRVQcow2State Date: Sun, 27 Oct 2019 00:25:09 +0300 Message-Id: <628a9a1220bf648ebe0b7570a1e630abb09c4abf.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" This patch adds the following new fields to BDRVQcow2State: - subclusters_per_cluster: Number of subclusters in a cluster - subcluster_size: The size of each subcluster, in bytes - subcluster_bits: No. of bits so 1 << subcluster_bits =3D subcluster_size Images without subclusters are treated as if they had exactly one, with subcluster_size =3D cluster_size. Signed-off-by: Alberto Garcia --- block/qcow2.c | 5 +++++ block/qcow2.h | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index 0bc69e6996..ed8b81c7b7 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1342,6 +1342,11 @@ static int coroutine_fn qcow2_do_open(BlockDriverSta= te *bs, QDict *options, } } =20 + s->subclusters_per_cluster =3D + has_subclusters(s) ? QCOW_MAX_SUBCLUSTERS_PER_CLUSTER : 1; + s->subcluster_size =3D s->cluster_size / s->subclusters_per_cluster; + s->subcluster_bits =3D ctz32(s->subcluster_size); + /* Check support for various header values */ if (header.refcount_order > 6) { error_setg(errp, "Reference count entry width too large; may not " diff --git a/block/qcow2.h b/block/qcow2.h index b3826b37c1..278ca41314 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -75,6 +75,8 @@ /* The cluster reads as all zeros */ #define QCOW_OFLAG_ZERO (1ULL << 0) =20 +#define QCOW_MAX_SUBCLUSTERS_PER_CLUSTER 32 + #define MIN_CLUSTER_BITS 9 #define MAX_CLUSTER_BITS 21 =20 @@ -277,6 +279,9 @@ typedef struct BDRVQcow2State { int cluster_bits; int cluster_size; int l2_slice_size; + int subcluster_bits; + int subcluster_size; + int subclusters_per_cluster; int l2_bits; int l2_size; int l1_size; --=20 2.20.1