The Friday 07 Mar 2014 à 16:20:42 (+0800), Fam Zheng wrote : > 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 <source size here> > > (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 > > 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 >
Hi Fam, I want to rebase my patches on top of yours but I have trouble applying your series to kevin/block-next. Is it based on it ? Best regards Benoît