From nobody Tue Nov 11 22:33:46 2025 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; 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; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1565997766; cv=none; d=zoho.com; s=zohoarc; b=ecwqhjDrI+PlbIidA/HdxnaLVGbG5coJRq34krpPEt7yrcFossThYH4OkmZLpj8bMqsJhhONysBi1Sk/s/w7n0Lei1AuMWG+HUjLBNj67VSPfmIJaBtsIfX6BEYK9QeL2NzsR5hTvP9ClFYuCeMDbacDVuouK62NETVlq3b5aAQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1565997766; 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:ARC-Authentication-Results; bh=vbGxroM8CLiUAQqNoccjrL9UKl4/3y2/7jCGzJoO6QY=; b=c+4fPyGsV2kNIc3fKynDQ75sRvAcFgA0789asFXnCCHhvT2yscfY8tfZtTP7HzJukfOb970Qr2upDRJ3RqrGMrvUACbEbxtWYF9B7eNRHKX4q0AVD1xwuKyb+76J0lnHuHrx51K1wvZlEsGXP6wX4BKJY2wUhvn9xafOdPikJng= ARC-Authentication-Results: i=1; mx.zoho.com; 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; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1565997766700520.1026569036728; Fri, 16 Aug 2019 16:22:46 -0700 (PDT) Received: from localhost ([::1]:33176 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hylYR-0000PL-4a for importer@patchew.org; Fri, 16 Aug 2019 19:22:43 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46344) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hylPf-0006NU-Py for qemu-devel@nongnu.org; Fri, 16 Aug 2019 19:13:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hylPd-0005rK-Gh for qemu-devel@nongnu.org; Fri, 16 Aug 2019 19:13:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55612) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hylPZ-0005k5-J2; Fri, 16 Aug 2019 19:13:33 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D327830860C5; Fri, 16 Aug 2019 23:13:32 +0000 (UTC) Received: from probe.bos.redhat.com (dhcp-17-187.bos.redhat.com [10.18.17.187]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2611B19C6A; Fri, 16 Aug 2019 23:13:32 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org Date: Fri, 16 Aug 2019 19:12:54 -0400 Message-Id: <20190816231318.8650-13-jsnow@redhat.com> In-Reply-To: <20190816231318.8650-1-jsnow@redhat.com> References: <20190816231318.8650-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.44]); Fri, 16 Aug 2019 23:13:32 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 12/36] block/backup: add 'always' bitmap sync policy 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: peter.maydell@linaro.org, jsnow@redhat.com, qemu-stable@nongnu.org, qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" This adds an "always" policy for bitmap synchronization. Regardless of if the job succeeds or fails, the bitmap is *always* synchronized. This means that for backups that fail part-way through, the bitmap retains a record of which sectors need to be copied out to accomplish a new backup using the old, partial result. In effect, this allows us to "resume" a failed backup; however the new back= up will be from the new point in time, so it isn't a "resume" as much as it is an "incremental retry." This can be useful in the case of extremely large backups that fail considerably through the operation and we'd like to not w= aste the work that was already performed. Signed-off-by: John Snow Reviewed-by: Max Reitz Message-id: 20190709232550.10724-13-jsnow@redhat.com Signed-off-by: John Snow --- block/backup.c | 27 +++++++++++++++++++-------- qapi/block-core.json | 5 ++++- 2 files changed, 23 insertions(+), 9 deletions(-) diff --git a/block/backup.c b/block/backup.c index 474f8eeae29..2be570c0bfd 100644 --- a/block/backup.c +++ b/block/backup.c @@ -278,18 +278,29 @@ static void backup_cleanup_sync_bitmap(BackupBlockJob= *job, int ret) { BdrvDirtyBitmap *bm; BlockDriverState *bs =3D blk_bs(job->common.blk); + bool sync =3D (((ret =3D=3D 0) || (job->bitmap_mode =3D=3D BITMAP_SYNC= _MODE_ALWAYS)) \ + && (job->bitmap_mode !=3D BITMAP_SYNC_MODE_NEVER)); =20 - if (ret < 0 || job->bitmap_mode =3D=3D BITMAP_SYNC_MODE_NEVER) { + if (sync) { /* - * Failure, or we don't want to synchronize the bitmap. - * Merge the successor back into the parent, delete nothing. + * We succeeded, or we always intended to sync the bitmap. + * Delete this bitmap and install the child. */ - bm =3D bdrv_reclaim_dirty_bitmap(bs, job->sync_bitmap, NULL); - assert(bm); - } else { - /* Everything is fine, delete this bitmap and install the backup. = */ bm =3D bdrv_dirty_bitmap_abdicate(bs, job->sync_bitmap, NULL); - assert(bm); + } else { + /* + * We failed, or we never intended to sync the bitmap anyway. + * Merge the successor back into the parent, keeping all data. + */ + bm =3D bdrv_reclaim_dirty_bitmap(bs, job->sync_bitmap, NULL); + } + + assert(bm); + + if (ret < 0 && job->bitmap_mode =3D=3D BITMAP_SYNC_MODE_ALWAYS) { + /* If we failed and synced, merge in the bits we didn't copy: */ + bdrv_dirty_bitmap_merge_internal(bm, job->copy_bitmap, + NULL, true); } } =20 diff --git a/qapi/block-core.json b/qapi/block-core.json index 06e34488a30..8344fbe2030 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1149,10 +1149,13 @@ # @never: The bitmap is never synchronized with the operation, and is # treated solely as a read-only manifest of blocks to copy. # +# @always: The bitmap is always synchronized with the operation, +# regardless of whether or not the operation was successful. +# # Since: 4.2 ## { 'enum': 'BitmapSyncMode', - 'data': ['on-success', 'never'] } + 'data': ['on-success', 'never', 'always'] } =20 ## # @MirrorCopyMode: --=20 2.21.0