From nobody Mon Feb 9 00:46:10 2026 Delivered-To: importer@patchew.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 ARC-Seal: i=1; a=rsa-sha256; t=1594397819; cv=none; d=zohomail.com; s=zohoarc; b=E0Ox2bXAMWZ0NAr1ZR5UorIGh/haPbLa0dwpIe75hZFKEsAu0ap/IV8ngTK3sKzE4DHRemCZWfDnxvPmmrQSHdthSQqwuWwoduQGylv9qDuWwPd1ltvbXIsdOOjH1AU6ZZI1H33wvB1QVp8edlCoEjguZxtbgMllS6YWcDubWM8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1594397819; 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=/yQAkav8k8jXe1E9CSu1YKeUgRZlXQ8ZbGUL+Lwq/rk=; b=lvHrGYsZbylhwsXLDrBudA8Lmz71ej57tZqJiyFPWVdTgV63AX/gtziiNFMM/d3OBjd2/LXJPgZVhjuViHzJrO1gO4OYNdF3hXxNC9J+eCvQzBezRRkO9+WWG3LyPlY+tC3veNeFB3OkWgT8/eDJUcl+7iPkcGU+Q1ABpx/rryw= ARC-Authentication-Results: i=1; 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 Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1594397819636810.716363575374; Fri, 10 Jul 2020 09:16:59 -0700 (PDT) Received: from localhost ([::1]:54372 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jtvhq-0007S9-8T for importer@patchew.org; Fri, 10 Jul 2020 12:16:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42352) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jtvf1-00023n-2M; Fri, 10 Jul 2020 12:14:03 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:43481) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jtvew-0004uw-OK; Fri, 10 Jul 2020 12:14:02 -0400 Received: from [81.0.43.0] (helo=perseus.local) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim) id 1jtveZ-0003jT-2T; Fri, 10 Jul 2020 18:13:35 +0200 Received: from berto by perseus.local with local (Exim 4.92) (envelope-from ) id 1jtveK-0001QE-L0; Fri, 10 Jul 2020 18:13:20 +0200 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=/yQAkav8k8jXe1E9CSu1YKeUgRZlXQ8ZbGUL+Lwq/rk=; b=b6IOfG+jOqYO2UwmAaN0eLPFUONl0tc75qxHMqIivAIHukpsx6rzgC5LmqdNqhBWnNzVmPwIsJGYFNJ4CILPJkHSlhyEcqYYPjGGfI+aDdI+a8SARtLIbI/Q/xybkEoxwUDqK4CeluTBmmiHNuxgPjTIQFFJX9wY3gKHPKOqa694bxe+BQtJbw04PBa2tl/rtMVl25FWPk6RI186FUnyL62y2zfsFUtl/3HyBy7Mu4SuNstcMW86O0W+TQvU3Bvjo0Ci7pFAh88WLzpWUByeGGH5mjuO3FsYgTSc0R8kGMBrnzu3Ud78Y3+ZQH1+vf0uHpLegLUdfpKoxhw8aTqTlA==; From: Alberto Garcia To: qemu-devel@nongnu.org Subject: [PATCH v11 03/34] qcow2: Add calculate_l2_meta() Date: Fri, 10 Jul 2020 18:12:45 +0200 Message-Id: X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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; Received-SPF: pass client-ip=178.60.130.6; envelope-from=berto@igalia.com; helo=fanzine.igalia.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/10 12:13:35 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x (no timestamps) [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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 , Alberto Garcia , qemu-block@nongnu.org, Derek Su , 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" handle_alloc() creates a QCowL2Meta structure in order to update the image metadata and perform the necessary copy-on-write operations. This patch moves that code to a separate function so it can be used from other places. Signed-off-by: Alberto Garcia Reviewed-by: Max Reitz --- block/qcow2-cluster.c | 77 +++++++++++++++++++++++++++++-------------- 1 file changed, 53 insertions(+), 24 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 2d9ae6481c..360da3f6b2 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1038,6 +1038,56 @@ void qcow2_alloc_cluster_abort(BlockDriverState *bs,= QCowL2Meta *m) } } =20 +/* + * For a given write request, create a new QCowL2Meta structure, add + * it to @m and the BDRVQcow2State.cluster_allocs list. + * + * @host_cluster_offset points to the beginning of the first cluster. + * + * @guest_offset and @bytes indicate the offset and length of the + * request. + * + * If @keep_old is true it means that the clusters were already + * allocated and will be overwritten. If false then the clusters are + * new and we have to decrease the reference count of the old ones. + */ +static void calculate_l2_meta(BlockDriverState *bs, + uint64_t host_cluster_offset, + uint64_t guest_offset, unsigned bytes, + QCowL2Meta **m, bool keep_old) +{ + BDRVQcow2State *s =3D bs->opaque; + unsigned cow_start_from =3D 0; + unsigned cow_start_to =3D offset_into_cluster(s, guest_offset); + unsigned cow_end_from =3D cow_start_to + bytes; + unsigned cow_end_to =3D ROUND_UP(cow_end_from, s->cluster_size); + unsigned nb_clusters =3D size_to_clusters(s, cow_end_from); + QCowL2Meta *old_m =3D *m; + + *m =3D g_malloc0(sizeof(**m)); + **m =3D (QCowL2Meta) { + .next =3D old_m, + + .alloc_offset =3D host_cluster_offset, + .offset =3D start_of_cluster(s, guest_offset), + .nb_clusters =3D nb_clusters, + + .keep_old_clusters =3D keep_old, + + .cow_start =3D { + .offset =3D cow_start_from, + .nb_bytes =3D cow_start_to - cow_start_from, + }, + .cow_end =3D { + .offset =3D cow_end_from, + .nb_bytes =3D cow_end_to - cow_end_from, + }, + }; + + qemu_co_queue_init(&(*m)->dependent_requests); + QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); +} + /* * 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, @@ -1436,35 +1486,14 @@ static int handle_alloc(BlockDriverState *bs, uint6= 4_t guest_offset, uint64_t requested_bytes =3D *bytes + offset_into_cluster(s, guest_off= set); int avail_bytes =3D nb_clusters << s->cluster_bits; int nb_bytes =3D MIN(requested_bytes, avail_bytes); - QCowL2Meta *old_m =3D *m; - - *m =3D g_malloc0(sizeof(**m)); - - **m =3D (QCowL2Meta) { - .next =3D old_m, - - .alloc_offset =3D alloc_cluster_offset, - .offset =3D start_of_cluster(s, guest_offset), - .nb_clusters =3D nb_clusters, - - .keep_old_clusters =3D keep_old_clusters, - - .cow_start =3D { - .offset =3D 0, - .nb_bytes =3D offset_into_cluster(s, guest_offset), - }, - .cow_end =3D { - .offset =3D nb_bytes, - .nb_bytes =3D avail_bytes - nb_bytes, - }, - }; - qemu_co_queue_init(&(*m)->dependent_requests); - QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); =20 *host_offset =3D alloc_cluster_offset + offset_into_cluster(s, guest_o= ffset); *bytes =3D MIN(*bytes, nb_bytes - offset_into_cluster(s, guest_offset)= ); assert(*bytes !=3D 0); =20 + calculate_l2_meta(bs, alloc_cluster_offset, guest_offset, *bytes, + m, keep_old_clusters); + return 1; =20 fail: --=20 2.20.1