From nobody Mon Feb 9 09:47:15 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=1590431158; cv=none; d=zohomail.com; s=zohoarc; b=JXFWWVGlZZtrYKi0u2VO/riGN0us2TFzPJtXmNWoiYnTs20FmpKjrJ9Mx58NvnccrzW3fUsqWgoSxH84CK/bgKvZeVDhu2v67OwnMgq+2m5Coqjp1zXJTWYVwzDYnUwf/iT8ZxuoXpc4a/maPeUmoE5njWzKcf9F+g0OgcfiGis= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1590431158; 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=d6IT11cylzvBF1dcJaRmHPWQW7ow7GwMMEq3EfPDc24=; b=HGad6w/TfM6QMUfd4juV2vgojFBVllV7FUepFubxP19v81caynYt3MzwYax1DgtzwvWyZ28juUtkqxSrKd4AD8XyopAzjKViMw25ycbUCTrRL7rjSqOe2Fv3SDlZHOAf9K/q1s/ig/Rl4FZfTK2IhsqiMDjk3p55XaVuYBBC6C4= 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 1590431158153872.09071363069; Mon, 25 May 2020 11:25:58 -0700 (PDT) Received: from localhost ([::1]:48380 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jdHnQ-00064Q-Pk for importer@patchew.org; Mon, 25 May 2020 14:25:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45234) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jdHXt-0003zW-IW; Mon, 25 May 2020 14:09:53 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:51066) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jdHXq-0007pt-0Y; Mon, 25 May 2020 14:09:53 -0400 Received: from [81.0.38.199] (helo=perseus.local) by fanzine.igalia.com with esmtpsa (Cipher TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim) id 1jdHXP-00088Y-HE; Mon, 25 May 2020 20:09:23 +0200 Received: from berto by perseus.local with local (Exim 4.92) (envelope-from ) id 1jdHXA-0002NX-9L; Mon, 25 May 2020 20:09:08 +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=d6IT11cylzvBF1dcJaRmHPWQW7ow7GwMMEq3EfPDc24=; b=DS3BqZ/Gw0fNjekOrlrCvmSJI8khW5/lqtlJKOSIqox3Hx+b6nb6fmeosIKZnMXBGUCkZGyVo8dx/Ribg+70F0bNhTVmFoz13wXCEPpOkszOrAc3CSUdU3ATzUdkxAtRJe47q5ir4xPuVaz/HGw6x4dez42keJPT6jWaeaw531oFdsMNmlXuJEAV2Rb8dd7pfJTr7xChagnMNt5929fssEDL/SQFCN8S2PkSCsYcZ/AbFEMkQ6ZOj4bszlJKIG7fmPtbKXO0kyu5EOLOkOnKsonwyvZQUx6287nGq6hLUq6zZhyx7nZR/KoxM1tAH1H5iJA8M4q5jJYEk+LgveS0/Q==; From: Alberto Garcia To: qemu-devel@nongnu.org Subject: [PATCH v7 25/32] qcow2: Update L2 bitmap in qcow2_alloc_cluster_link_l2() Date: Mon, 25 May 2020 20:08:50 +0200 Message-Id: <255326ac806cdd1796857363dd8a6b26d5735f81.1590429901.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 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 = 2020/05/25 14:09:23 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_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN 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" The L2 bitmap needs to be updated after each write to indicate what new subclusters are now allocated. This needs to happen even if the cluster was already allocated and the L2 entry was otherwise valid. In some cases however a write operation doesn't need change the L2 bitmap (because all affected subclusters were already allocated). This is detected in calculate_l2_meta(), and qcow2_alloc_cluster_link_l2() is never called in those cases. Signed-off-by: Alberto Garcia Reviewed-by: Eric Blake --- block/qcow2-cluster.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index edfc8ea91c..2276cee6d6 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1061,6 +1061,24 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs= , QCowL2Meta *m) assert((offset & L2E_OFFSET_MASK) =3D=3D offset); =20 set_l2_entry(s, l2_slice, l2_index + i, offset | QCOW_OFLAG_COPIED= ); + + /* Update bitmap with the subclusters that were just written */ + if (has_subclusters(s)) { + uint64_t l2_bitmap =3D get_l2_bitmap(s, l2_slice, l2_index + i= ); + unsigned written_from =3D m->cow_start.offset; + unsigned written_to =3D m->cow_end.offset + m->cow_end.nb_byte= s ?: + m->nb_clusters << s->cluster_bits; + int first_sc, last_sc; + /* Narrow written_from and written_to down to the current clus= ter */ + written_from =3D MAX(written_from, i << s->cluster_bits); + written_to =3D MIN(written_to, (i + 1) << s->cluster_bits); + assert(written_from < written_to); + first_sc =3D offset_to_sc_index(s, written_from); + last_sc =3D offset_to_sc_index(s, written_to - 1); + l2_bitmap |=3D QCOW_OFLAG_SUB_ALLOC_RANGE(first_sc, last_sc + = 1); + l2_bitmap &=3D ~QCOW_OFLAG_SUB_ZERO_RANGE(first_sc, last_sc + = 1); + set_l2_bitmap(s, l2_slice, l2_index + i, l2_bitmap); + } } =20 =20 --=20 2.20.1