From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40328) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WMubB-0005sN-CT for qemu-devel@nongnu.org; Mon, 10 Mar 2014 03:26:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WMub6-00074C-Jj for qemu-devel@nongnu.org; Mon, 10 Mar 2014 03:26:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:2891) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WMub6-000746-Bj for qemu-devel@nongnu.org; Mon, 10 Mar 2014 03:26:04 -0400 From: Fam Zheng Date: Mon, 10 Mar 2014 15:25:56 +0800 Message-Id: <1394436370-8908-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v17 00/14] Drop in_use from BlockDriverState and enable point-in-time snapshot exporting over NBD List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, benoit.canet@irqsave.net, rjones@redhat.com, jcody@redhat.com, armbru@redhat.com, ptoscano@redhat.com, imain@redhat.com, stefanha@redhat.com, pbonzini@redhat.com This series adds for point-in-time snapshot NBD exporting based on blockdev-backup (variant of drive-backup with existing device as target). We get a thin point-in-time snapshot by COW mechanism of drive-backup, and export it through built in NBD server. The steps are as below: 1. (SHELL) qemu-img create -f qcow2 BACKUP.qcow2 (Alternatively we can use -o backing_file=RUNNING-VM.img to omit explicitly providing the size by ourselves, but it's risky because RUNNING-VM.qcow2 is used r/w by guest. Whether or not setting backing file in the image file doesn't matter, as we are going to override the backing hd in the next step) 2. (QMP) blockdev-add backing=source-drive file.driver=file file.filename=BACKUP.qcow2 id=target0 if=none driver=qcow2 (where source-drive is the running BlockDriverState name for RUNNING-VM.img. This patch implements "backing=" option to override backing_hd for added drive) 3. (QMP) blockdev-backup device=source-drive sync=none target=target0 (this is the QMP command introduced by this series, which use a named device as target of drive-backup) 4. (QMP) nbd-server-add device=target0 When image fleecing done: 1. (QMP) block-job-cancel device=source-drive 2. (HMP) drive_del target0 3. (SHELL) rm BACKUP.qcow2 v17: Rebase to current master. v16: Address review comments from Jeff and Markus (thanks for reviewing!) (A side-by-side diff of v15 -> v16: http://goo.gl/1goc6S) [03/14] block: Replace in_use with operation blocker Improve error message. (Markus) [05/14] block: Add bdrv_set_backing_hd() in bdrv_set_backing_hd: * Don't call bdrv_ref and bdrv_unref. (Jeff) * Add "bs->open_flags &= ~BDRV_O_NO_BACKING". (Jeff) in bdrv_open_backing_file: * Remove unnecessary "bs->backing_hd = NULL;". (Jeff) * Don't get wrong refcnt on backing_hd. (Jeff) in bdrv_append: * Remove unnessary backing_file and backing_format copy, it's taken care of in bdrv_set_backing_hd(). (Jeff) [06/14] block: Add backing_blocker in BlockDriverState Add call to bdrv_ref() since bdrv_set_backing_hd() doesn't do it now. [08/14] block: Support dropping active in bdrv_drop_intermediate Verify active, top, base are in the same backing chain. (Jeff) Remember to change backing file when base != NULL. (Jeff) [09/14] stream: Use bdrv_drop_intermediate and drop close_unused_images Drop more unnecessary code. (Jeff) Thanks, Fam Fam Zheng (14): block: Add BlockOpType enum block: Introduce op_blockers to BlockDriverState block: Replace in_use with operation blocker block: Move op_blocker check from block_job_create to its caller block: Add bdrv_set_backing_hd() block: Add backing_blocker in BlockDriverState block: Parse "backing" option to reference existing BDS block: Support dropping active in bdrv_drop_intermediate stream: Use bdrv_drop_intermediate and drop close_unused_images qmp: Add command 'blockdev-backup' block: Allow backup on referenced named BlockDriverState block: Add blockdev-backup to transaction qemu-iotests: Test blockdev-backup in 055 qemu-iotests: Image fleecing test case 083 block-migration.c | 7 +- block.c | 314 +++++++++++++++++++++++++++------------- block/backup.c | 26 ++++ block/commit.c | 2 +- block/mirror.c | 1 + block/stream.c | 42 +----- blockdev.c | 122 ++++++++++++++-- blockjob.c | 14 +- hw/block/dataplane/virtio-blk.c | 19 ++- include/block/block.h | 29 +++- include/block/block_int.h | 9 +- include/block/blockjob.h | 3 + qapi-schema.json | 50 +++++++ qmp-commands.hx | 44 ++++++ tests/qemu-iotests/055 | 275 +++++++++++++++++++++++++++++------ tests/qemu-iotests/055.out | 4 +- tests/qemu-iotests/083 | 99 +++++++++++++ tests/qemu-iotests/083.out | 5 + tests/qemu-iotests/group | 1 + 19 files changed, 854 insertions(+), 212 deletions(-) create mode 100755 tests/qemu-iotests/083 create mode 100644 tests/qemu-iotests/083.out -- 1.9.0