Hi all! These series introduce backup-top driver. It's a filter-node, which do copy-before-write operation. Mirror uses filter-node for handling guest writes, let's move to filter-node (from write-notifiers) for backup too.
I decided to postpone all these "preparation" and "improvement" series, as it seems we will never do the core thing in such way. v9: 01: rebased, it's from "backup improvements" series 02-05: new patches, introduction of block-copy 06: unchanged 07-08: new iotests preparation 10-11: unchanged 12: backup-top filter is simplified: it don't do copy operation by hands but through block-copy, and it don't have second "target" child anymore. So the state is reduced to only two fields: block-copy state and "active". What else? 1. filter-node-name parameter added 2. "active" parameter. I failed on my way to make bdrv_append firstly do bdrv_replace_node and then bdrv_set_backing_hd, as it leads to much problems, block-layer is unprepared for child-less filters. So, it's a lot simpler to cheat a bit with permissions, and don't require unshared WRITE during appending. 3. filter is not finished in this patch, as block_copy is not finished too, you can see a TODO and abort() in backup_top_cbw. 13: - filter-node-name added - backup_clean simplified: don't bother with keeping block job blk on backup-top filter, it's not necessary. - locking is all done in block-copy code - itests changed in different manner - I'm afraid that's not a full list, patch really changed significantly. The series also needs one small fix: "[PATCH] block: fix permission update in bdrv_replace_node" Based-on: <20190824100740.61635-1-vsement...@virtuozzo.com> Vladimir Sementsov-Ogievskiy (13): block/backup: fix backup_cow_with_offload for last cluster block/backup: split shareable copying part from backup_do_cow block/backup: introduce BlockCopyState block/backup: adjust block-copy functions style block: move block_copy from block/backup.c to separate file block: teach bdrv_debug_breakpoint skip filters with backing iotests: prepare 124 and 257 bitmap querying for backup-top filter iotests: 257: drop unused Drive.device field iotests: 257: drop device_add block/io: refactor wait_serialising_requests block: add lock/unlock range functions block: introduce backup-top filter driver block/backup: use backup-top instead of write notifiers qapi/block-core.json | 8 +- block/backup-top.h | 37 ++ include/block/block-copy.h | 59 +++ include/block/block_int.h | 5 + block.c | 34 +- block/backup-top.c | 241 ++++++++++++ block/backup.c | 411 +++---------------- block/block-copy.c | 320 +++++++++++++++ block/io.c | 68 +++- block/replication.c | 2 +- blockdev.c | 1 + block/Makefile.objs | 3 + block/trace-events | 14 +- tests/qemu-iotests/056 | 2 +- tests/qemu-iotests/124 | 3 +- tests/qemu-iotests/257 | 81 ++-- tests/qemu-iotests/257.out | 714 ++++++++++++++-------------------- tests/qemu-iotests/iotests.py | 22 ++ 18 files changed, 1163 insertions(+), 862 deletions(-) create mode 100644 block/backup-top.h create mode 100644 include/block/block-copy.h create mode 100644 block/backup-top.c create mode 100644 block/block-copy.c -- 2.18.0