Hi all!
We have image fleecing scheme to export point-in-time state of active
disk (iotest 222):
backup(sync=none)
┌───────────────────────────────────────┐
▼ │
┌────────────┐ ┌────────────────┐ backing ┌─────────────┐
│ NBD export │ ─── │ temp qcow2 img │ ───────────────────▶ │ active disk │
└────────────┘ └────────────────┘ └─────────────┘
▲
┌────────────┐ │
│ guest blk │ ──────────────────────────────────────────────┘
└────────────┘
Actually, backup job inserts a backup-top filter, so in detail it looks
like:
backup(sync=none)
┌───────────────────────────────────────┐
▼ │
┌────────────┐ ┌────────────────┐ backing ┌─────────────┐
│ NBD export │ ─── │ temp qcow2 img │ ───────────────────▶ │ active disk │
└────────────┘ └────────────────┘ └─────────────┘
▲ ▲
│ target │
│ │
┌────────────┐ ┌────────────────┐ backing │
│ guest blk │ ──▶ │ backup-top │ ───────────────────────┘
└────────────┘ └────────────────┘
And job does nothing here. In a new blockdev world user is intended to
operate on node level, and insert/remove filters by hand. Let's get rid
of job in the scheme:
┌────────────┐ ┌────────────────┐ backing ┌─────────────┐
│ NBD export │ ─── │ temp qcow2 img │ ───────────────────▶ │ active disk │
└────────────┘ └────────────────┘ └─────────────┘
▲ ▲
│ target │
│ │
┌────────────┐ ┌────────────────┐ backing │
│ guest blk │ ──▶ │ backup-top │ ───────────────────────┘
└────────────┘ └────────────────┘
The series prepares qom-set to make possible inserting filters above
root node (patches 01-04), rename backup-top to copy-before-write, do
other preparations for publishing the filter, and finally publish it,
add qapi interface and test new fleecing scheme in 222.
Vladimir Sementsov-Ogievskiy (21):
block: introduce bdrv_replace_child_bs()
block: introduce blk_replace_bs
qdev-properties: PropertyInfo: add realized_set_allowed field
qdev: allow setting drive property for realized device
block: rename backup-top to copy-before-write
block/backup: drop support for copy_range
block-copy: always set BDRV_REQ_SERIALISING flag
block/backup: stricter backup_calculate_cluster_size()
block/backup: move cluster size calculation to block-copy
block/copy-before-write: relax permission requirements when no parents
block/copy-before-write: use file child instead of backing
block/copy-before-write: bdrv_cbw_append(): replace child at last
block/copy-before-write: introduce cbw_init()
block/copy-before-write: cbw_init(): rename variables
block/copy-before-write: cbw_init(): use file child after attaching
block/copy-before-write: cbw_init(): use options
block/block-copy: switch to fully set bitmap by default
block/block-copy: make setting progress optional
block/copy-before-write: make public block driver
qapi: publish copy-before-write filter
itotests/222: add test-case for copy-before-write filter
qapi/block-core.json | 22 +-
block/{backup-top.h => copy-before-write.h} | 26 +-
include/block/block-copy.h | 4 +-
include/block/block.h | 2 +
include/hw/qdev-properties.h | 1 +
include/sysemu/block-backend.h | 1 +
block.c | 36 +++
block/backup-top.c | 253 -------------------
block/backup.c | 115 ++-------
block/block-backend.c | 8 +
block/block-copy.c | 95 +++++++-
block/copy-before-write.c | 257 ++++++++++++++++++++
hw/core/qdev-properties-system.c | 30 ++-
hw/core/qdev-properties.c | 6 +-
MAINTAINERS | 4 +-
block/meson.build | 2 +-
tests/qemu-iotests/222 | 56 ++++-
tests/qemu-iotests/222.out | 72 ++++++
tests/qemu-iotests/283 | 35 ++-
tests/qemu-iotests/283.out | 4 +-
20 files changed, 606 insertions(+), 423 deletions(-)
rename block/{backup-top.h => copy-before-write.h} (56%)
delete mode 100644 block/backup-top.c
create mode 100644 block/copy-before-write.c
--
2.29.2