{"id":806817,"url":"http://patchwork.ozlabs.org/api/1.0/patches/806817/?format=json","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.0/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com>","date":"2017-08-29T00:13:54","name":"[19/79] block: Reuse bs as backing hd for drive-backup sync=none","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"af2955725b2f3bf0dc2e3ca0501ceb9d305d3b3d","submitter":{"id":5549,"url":"http://patchwork.ozlabs.org/api/1.0/people/5549/?format=json","name":"Michael Roth","email":"mdroth@linux.vnet.ibm.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com/mbox/","series":[{"id":281,"url":"http://patchwork.ozlabs.org/api/1.0/series/281/?format=json","date":"2017-08-29T00:13:45","name":"Patch Round-up for stable 2.9.1, freeze on 2017-09-04","version":1,"mbox":"http://patchwork.ozlabs.org/series/281/mbox/"}],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/806817/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xh8W86y2wz9s65\n\tfor ;\n\tTue, 29 Aug 2017 10:23:32 +1000 (AEST)","from localhost ([::1]:41914 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dmUJW-0007VT-LS\n\tfor incoming@patchwork.ozlabs.org; Mon, 28 Aug 2017 20:23:30 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:47528)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dmUCC-0000v0-IA\n\tfor qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:59 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dmUCA-0005Bf-ET\n\tfor qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:56 -0400","from mx0a-001b2d01.pphosted.com ([148.163.156.1]:48696)\n\tby eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from )\n\tid 1dmUCA-0005Af-3t\n\tfor qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:54 -0400","from pps.filterd (m0098396.ppops.net [127.0.0.1])\n\tby mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id\n\tv7T0E85d005466\n\tfor ; Mon, 28 Aug 2017 20:15:53 -0400","from e12.ny.us.ibm.com (e12.ny.us.ibm.com [129.33.205.202])\n\tby mx0a-001b2d01.pphosted.com with ESMTP id 2cmvjejk4c-1\n\t(version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT)\n\tfor ; Mon, 28 Aug 2017 20:15:52 -0400","from localhost\n\tby e12.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use\n\tOnly! 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Violators will be prosecuted; \n\tMon, 28 Aug 2017 20:15:49 -0400","from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com\n\t[9.57.199.106])\n\tby b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP\n\tid v7T0FmuQ24182974; Tue, 29 Aug 2017 00:15:48 GMT","from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id 025E92803E;\n\tMon, 28 Aug 2017 20:15:42 -0400 (EDT)","from localhost (unknown [9.80.85.217])\n\tby b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP id BE47C2803F;\n\tMon, 28 Aug 2017 20:15:41 -0400 (EDT)"],"From":"Michael Roth ","To":"qemu-devel@nongnu.org","Date":"Mon, 28 Aug 2017 19:13:54 -0500","X-Mailer":"git-send-email 2.7.4","In-Reply-To":"<1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com>","References":"<1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com>","X-TM-AS-GCONF":"00","x-cbid":"17082900-0048-0000-0000-000001DAEA2F","X-IBM-SpamModules-Scores":"","X-IBM-SpamModules-Versions":"BY=3.00007630; HX=3.00000241; KW=3.00000007;\n\tPH=3.00000004; SC=3.00000226; SDB=6.00909028; UDB=6.00455849;\n\tIPR=6.00689279; \n\tBA=6.00005557; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009;\n\tZB=6.00000000; \n\tZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016909;\n\tXFM=3.00000015; UTC=2017-08-29 00:15:50","X-IBM-AV-DETECTION":"SAVI=unused REMOTE=unused XFE=unused","x-cbparentid":"17082900-0049-0000-0000-000042619399","Message-Id":"<1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com>","X-Proofpoint-Virus-Version":"vendor=fsecure engine=2.50.10432:, ,\n\tdefinitions=2017-08-28_13:, , signatures=0","X-Proofpoint-Spam-Details":"rule=outbound_notspam policy=outbound score=0\n\tspamscore=0 suspectscore=1\n\tmalwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam\n\tadjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000\n\tdefinitions=main-1708290001","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy]","X-Received-From":"148.163.156.1","Subject":"[Qemu-devel] [PATCH 19/79] block: Reuse bs as backing hd for\n\tdrive-backup sync=none","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Cc":"Kevin Wolf , Fam Zheng ,\n\tqemu-stable@nongnu.org","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"},"content":"From: Fam Zheng \n\nOpening the backing image for the second time is bad, especially here\nwhen it is also in use as the active image as the source. The\ndrive-backup job itself doesn't read from target->backing for COW,\ninstead it gets data from the write notifier, so it's not a big problem.\nHowever, exporting the target to NBD etc. won't work, because of the\nlikely stale metadata cache.\n\nUse BDRV_O_NO_BACKING in this case and manually set up the backing\nBdrvChild.\n\nCc: qemu-stable@nongnu.org\nSigned-off-by: Fam Zheng \nSigned-off-by: Kevin Wolf \n(cherry picked from commit fc0932fdcfc3e5cafa3641e361b681c07f639812)\nSigned-off-by: Michael Roth \n---\n blockdev.c | 15 ++++++++++++++-\n 1 file changed, 14 insertions(+), 1 deletion(-)","diff":"diff --git a/blockdev.c b/blockdev.c\nindex e2f9c1e..841200e 100644\n--- a/blockdev.c\n+++ b/blockdev.c\n@@ -3170,6 +3170,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n Error *local_err = NULL;\n int flags;\n int64_t size;\n+ bool set_backing_hd = false;\n \n if (!backup->has_speed) {\n backup->speed = 0;\n@@ -3220,6 +3221,8 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n }\n if (backup->sync == MIRROR_SYNC_MODE_NONE) {\n source = bs;\n+ flags |= BDRV_O_NO_BACKING;\n+ set_backing_hd = true;\n }\n \n size = bdrv_getlength(bs);\n@@ -3246,7 +3249,9 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n }\n \n if (backup->format) {\n- options = qdict_new();\n+ if (!options) {\n+ options = qdict_new();\n+ }\n qdict_put_str(options, \"driver\", backup->format);\n }\n \n@@ -3257,6 +3262,14 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n \n bdrv_set_aio_context(target_bs, aio_context);\n \n+ if (set_backing_hd) {\n+ bdrv_set_backing_hd(target_bs, source, &local_err);\n+ if (local_err) {\n+ bdrv_unref(target_bs);\n+ goto out;\n+ }\n+ }\n+\n if (backup->has_bitmap) {\n bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);\n if (!bmap) {\n","prefixes":["19/79"]}